Phẫu Thuật Giảm Béo (Bariatric Surgery)

Anaesthesia in Bariatric Surgery
33
Opiates
Drugs
Fentanyl
Alfentanyl
Morfina
Pharmacokinetic
None
Increase of elimination
No information
alterations
half time
available
Clinical evidence
None
Dose/kg sec. LBW
None
Local anaesthetics
Drugs
Xilocain
Bupivacain
Pharmacokinetic alterations
1. ↑Vd
No information available
2. = Vd/kg
Clinical evidence
1. = Dose/kg e.v.
Unpredictable extension
2. ↓Dose/kg ( 25%)
of subaracnoidal block
Volatile agents
Drugs
N2O
Enflurane
Sevoflurane
Pharmacokinetic
No information available
1. ↓Partition
None
alterations
coefficient
2. High levels of
fluoride catabolites
Clinical evidence
Impossibility to use high
1. ↓MAC****
None
percentages of FiO2
2. ↑risk by fluoride
metabolites
Vd = Distribution volume; ** = correct weight = ideal weight + (0.4 × excess of weight) ***
LBW = Lean body weight MAC = ****Minimum alveolar concentration.
half life, even though the clearance values are normal. Doses between
4 and 7 mg/kg of the ideal body weight are suggested.38
Benzodiazepines
Benzodiazepines behave in almost the same way as thiopental and there
are no precise recommendations about the dosage. Diazepam has a
volume of systemic distribution which is almost the same in obese and
normal weight patients, so increased doses should be used. An increased
half life has been demonstrated for midazolam: 2.7 hours in non obese
patients, and 8.4 hours in obese subjects.39

Propofol
This drug shows normal distribution at steady state and an accelerated clear-
ance so that after 24 hours of infusion there is no accumulation present.40
An empirical formula has been used for the drug dosage, correlated to
the correct body weight (correct weight = ideal weight + [0.4 × excess of
weight]), which has highlighted how the pharmacokinetics of propofol are
similar to those observed in non-obese patients.41
Synthetic opiates
This group behaves differently. There are no variations in the kinetics as
far as fentanil is concerned, but there is an increase in the elimination half
life for alfentanil and sulfentanil.37 Among the new opiates, remifentanil
is worthy of particular attention for its pharmacokinetic characteristics
which can be summarized as follows:
•
short action onset (1 minute);
•
rapid distribution;
•
half life singularly short and independent of the duration of infusion
(3.7 minutes after an infusion of 240 minutes);
•
ultra-short action duration (5–10 minutes);
•
organ-independent metabolism: the drug is hydrolyzed by plasmatic
and tissue esterase with the formation of substantially inactive
derivatives.
These characteristics make remifentanil extremely adaptable with regards
to dosage levels, suitable for administration for a short or long period of
time without protracting the recovery time. Furthermore, the steady state
is reached in 5–10 minutes. A precise titration of the analgesia is possible,
so a rapid recovery, predictable and independent of the dose and the dura-
tion of infusion is therefore possible.
Due to the high percentage of adipose tissue and therefore an
increased accumulation of lipophilic drugs in the obese patient, a pro-
longed elimination half life is observed. In fact, the majority of authors
have highlighted a reduction in the clearance and in the distribution
volume of such drugs.42
34
E. Pizzirani and G. Calcarella

A study by Egan43 has revealed that in the obese patient, the dosage of
remifentanil, correlated to the IBW rather than to the total body weight
(TBW), has the same tendency as that found in the normal population.
The absolute distribution volume and clearance (not correlated to the body
weight) are similar in both groups, but if correlated to the total body
weight are reduced in the first group. Instead, these same parameters show
a strict correlation to lean body mass (LBM). It is very complicated to
extrapolate this value in everyday practice, therefore, the authors advise
us to refer to IBW, which is representative of LBM, when we calculate the
optimal dosage of the opiate.
Finally, it is correct to highlight that the short ECS of remifentanil
should be used in laparoscopic surgery in obese patients, resulting in an
early recovery from surgery and an early discharge from hospital.9
Depolarizing muscle relaxants
Succinylcholine (SCH)
This is used in different dosages. The obese patient generally has
increased pseudo-cholinesterase activity and it is advisable to use doses of
1.2–1.5 mg/kg on the basis of the ideal body weight. Moreover, studies
show different behaviours, since some have revealed that dosages of
120–140 mg were satisfactory as far as the tracheal intubation is con-
cerned (in patients whose weight is over 140 kg), whereas others have
successfully used dosages of 75–100 mg (in patients whose weight is
between 130 and 135 kg).
More recently in a study by Lemmens et al.44 the administration of a
dose of 1 mg/kg of SCH has been studied on the basis of the ideal body
weight, lean body weight and total body weight. The study reveals that
complete paralysis suitable for an optimal laryngoscopy can be obtained
with the dose of 1 mg correlated to the total weight.
Pancuronium bromide
Pancuronium bromide is a drug with low liposolubility. Some authors main-
tain dosages that do not need to be altered from those used in non-obese
patients,45 but according to other authors, higher dosages would be needed.46
Anaesthesia in Bariatric Surgery
35

Vecuronium
This drug should be administered according to ideal body weight.17 In fact
the use of doses proportional to actual body weight leads to a prolonged
recovery time, which, according to some authors, correlates only with
overdosage, but according to others, with the modification of hepatic and
renal clearance and with a higher haematic distribution volume.47
Atracurium
Atracurium is used in doses per kilogram of body weight, and has the same
recovery time for both obese and non-obese patients when used as such.48
There are no variations in the distribution volume, clearance or elimination
half life. This is probably because this last molecule is independent of the
function of the organ, even if major haematic concentrations have been
found, when compared with those found in non-obese patients. The mean-
ing of this is not clear; the hypothesis is that alterations have taken place in
the proteic link or in the acetylcholine receptors.49
Nitrous oxide
A gaseous, inhaling agent with low liposolubility and which is difficult to
metabolize, this represents a rational choice in the obese patient. The only
limitation is the impossibility of using high percentages of O2 in the inspi-
ratory mixture in order to always provide adequate oxygenation.
Volatile agents
It was suggested in the past that these resulted in a prolonged recovery
time as a result of the accumulation in the adipose tissue.50,51 This has not
been confirmed by further studies, which suggests that reduced tissue
perfusion could inhibit the formation of deposits of these substances.
Halothane and enfluorane are metabolized producing high levels of
urinary catabolites,50,52 whereas isofluorane and desfluorane, which are
less metabolized, are considered the drugs of choice. With regards to
sevofluorane, the first studies on its biotransformation and plasmatic flu-
oride levels gave similar results in both obese patients and those of normal
36
E. Pizzirani and G. Calcarella

weight. In particular Frink et al.53 demonstrated that, with a Minimal
Alveolar Concentration (MAC) = 2.05 (1.4 MAC/h) the concentrations of
fluoride ions during and after anaesthesia did not differ in either group.
In contrast, Higuchi et al.,54 with a MAC of a much higher dosage of
sevofluorane (MAC 4.5/h), found haematic peaks of fluorides higher than
50 nmo/l for about two hours and an increased urinary secretion of the
same in the first 24 hours without the occurrence of alterations in the renal
functionality in the first 48 hours after surgery.
In the same study, the authors compared isofluorane and sevofluo-
rane, showing that there are no differences in the MAC-awake of the two
agents (0.14 per cent for isofluorane; 0.17 per cent for sevofluorane), even
when varying their concentration, the duration of the inhalation and the
class of obesity.54
Local anaesthetics and opiates
Intrathecally administered, the kinetics and dynamics of these drugs have
only been partially explained. It is understood that as a result of the higher
content of extradural fat, a greater initial dose of the drug is required, and this
factor together with the venous blockage, which reduces the dimensions of
the extradural space, would increase the segmental distribution of the anaes-
thetic, with anaesthetic levels larger than those we would have expected.
For these reasons doses of the drug required for surgery analgesia,
calculated on the basis of the total body weight, must be reduced by
20–25 per cent,55–57 whereas for the post-operative analgesia variations are
unnecessary for non-obese patients.58
Evaluating the Patient Before Anaesthesia
Obese patients with positive anamnesis regarding pneumopathy and/or
cardiopathy who are subject to abdominal or thoracic surgery present an
increased morbidity due to the higher incidence of post-operative
complications.59 For hysterectomies via the abdomen and in major abdominal
surgery60 the mortality is increased. Emergency surgery involves an additional
risk, even if the data at our disposal do not always agree on this subject.
Different anaesthesiological approaches have been recommended, but
no technique has demonstrated advantages when compared to others.
Anaesthesia in Bariatric Surgery
37

Pre-operative visit
A scrupulous evaluation is necessary during the pre-operative visit in
order to assess the cardiovascular, pulmonary and metabolic situation.
A meticulous anatomic inspection is needed in order to find predictable
parameters for difficult intubations. As usual, it is in this phase that all
necessary information must be obtained, including the chosen anaesthesi-
ological technique and its related problems. It also covers any need for
post-operative analgesic treatments such as epidural analgesia and possi-
ble admission to ITU. The usefulness of early post-operative mobilization
should be emphasized and the opportunity taken to highlight the advan-
tages of both passive and active physiotherapy. It is useful to stress that
the overweight person has often been taking antidepressants and/or seda-
tives for years and is therefore subject to a psychological weakness which
strongly affects his behaviour both in the pre- and post-operative phases.
Furthermore it is vital that a trusting relationship is formed between the
anaesthetist and the patient. This should be based on an exhaustive
exchange of information, which is fundamental in achieving a calm induc-
tion phase and it is also an aid to achieving a post-operative regaining of
consciousness without uncontrolled reactions.
Cardiovascular evaluation
This is based on the study of:
•
ECG (12 derivations) in order to look for ventricular (left or right)
ischemia and hypertrophy signs;
•
the measurement of non invasive blood pressure (NIBP) with a cuff
as large as the patient’s arm (since the standard one easily overesti-
mates the real values of the blood pressure);
•
a chest X-ray, used to check for myocardial hypertrophia and/or signs
of pulmonary congestion and atelectasic areas.
The presence of increased cardiac diameters together with a hypertrophic
left ventricular wall is frequently associated with a hypertensive status.
This condition results in a normal ventricular reaction to exercise, which
38
E. Pizzirani and G. Calcarella

does not occur in the obese when there is no increase in the augmentation
of the left ventricle, if body weight is more than 100 pounds in excess of
the norm. Instead, in patients whose weight exceeds 170 per cent of the
ideal, a decrease in the ventricular reaction to the effort occurs with the
progressive increase in the thickness of the left ventricle.61 This is partic-
ularly significant as the cardiovascular stress suffered by patients in the
peri-operative period is similar to that observed during physical effort.62
Respiratory apparatus evaluation
This is still based on the study of the chest X-ray, pulmonary function
tests and arterial blood–gas analysis in both sitting and supine positions.
In anamnesis we have to look for episodes of obstructive apnoea occur-
ring during sleep, secondary to obstructions and/or closing of the upper
airways.63
Haematochemical evaluation
Evaluation includes:
•
determining the haemoglobin level for evidence of polycythaemia
which must suggest the presence of chronic hypoxia;
•
serum chemistry studies;
•
renal and hepatic functionality tests;
•
a study of coagulation parameters.
Finally, in the case of positive anamnesis a precise definition of thyroid
function is recommended considering the serious haemodynamic disor-
ders due to thyroid disease which may occur in both the intra- and
post-operative phases.
The pre-operative visit finishes with the search for possible phar-
macological therapies which could interfere with anaesthesia, for
example amphetamine,64 anti-hypertensive drugs, antidepressants, oral
anti-diabetic drugs and treatments with insulin. All of these are fre-
quently found in the treatment of different organ pathologies affecting
the obese patient, even though they could create problems that are
Anaesthesia in Bariatric Surgery
39

difficult to resolve in both the intra- and post-operative phases. It is not
recommended that treatment be varied from that which would be given
to a person of normal weight, with the exception of post-operative
glycaemia for which one should remain particularly alert.
Pre-medication
Opinions vary on the use of sedative and opiate drugs in pre-medication
due to the concrete risk of causing prolonged respiratory depression that
would be hard to treat.65 Opiates should certainly be avoided, whereas
short and ultra short action duration benzodiazepines (midazolam) seem
not to cause problems of this kind.66,67 These drugs should be adminis-
trated by intravenous injections or sublingual pills, since subcutaneous
and intramuscular administration involves a certain level of unpredictable
absorption. In cases where a patient needs to be intubated whilst con-
scious and at discretion in other cases, it is good practice to administrate
a vagolytic agent to reduce possible sialorrhoea. Anti-H2 drugs, such as
Ranitidine (100 mg e.v.), are better than Cimetidine for their more pro-
longed action and lack of side effects on the hepatic metabolism, and
Metoclopramide, a prokinetic drug, which has a constrictor effect on the
oesophageal sphincter.65 This pre-treatment in the obese patient is always
necessary because unexpected and difficult orotracheal intubation (OTI)
is frequent. This can lead to repeated attempts to intubate the patient by
laryngoscopy with the possibility that regurgitated gastric juice might end
up being accidentally inhaled.
Intubation
Particular attention should be paid to all the parameters that can predict a
difficult intubation. Morbidly obese patients represent a difficult test even
for a skilled anaesthetist since they are the extreme expression of
unfavourable anatomic conditions.68
In synthesis, these patients present all or part of the following
‘negative’ characteristics:
•
large tongue;
•
poor cervical spine mobility;
40
E. Pizzirani and G. Calcarella

•
limited atlanto-occipital articulation;
•
accumulation of fat in the oropharyngeal spaces;
•
short or ‘absent’ neck.
Poor cervical spine mobility is present at different levels and it is at
times worsened by the presence of a conspicuous adipose gibbus which
does not allow the extension of the head over the neck. Furthermore, the
obese have conspicuous accumulations of tissue in the para-tonsilar and
para-glottic areas that can mask both the visibility and the accessibility of
the glottis during the laryngoscopy.56
A large tongue is highlighted by the characteristic print of the teeth on
the lateral edges of the tongue and by the disproportion between the latter
and the oral cavity.
Together with these evident anatomic limitations we have to consider
pathophysiologic alterations which do not allow exploration of the air-
ways by laryngoscopy during sedation. This depends on the fact that these
patients are very often affected by Obstructive Sleep Apnoea Syndrome
(OSAS) and by other ventilation disorders due to the obstruction of the
pharynx–larynx area that make spontaneous breathing difficult.
Sometimes a modest degree of sedation can unbalance an already precar-
ious situation and cause a sudden fall of coronary flow rate (CFR)
resulting in acute respiratory insufficiency.55,69 It is important to correlate
the problematic OTI in the obese patient with ‘difficult airways’ and
evaluate according to external parameters such as:
•
Mallampati classification (to evaluate the relative dimensions of the
tongue with respect to the oral and pharyngeal capacity);
•
thyromental distance (to evaluate the mandibular space);
•
mobility of atlanto-occipital and temporo-mandibulary articulations;
•
view of head and neck seen opposite and in profile (to evaluate the
morphologic characteristics such as dimensions, shape, congenital
anomalies).
If we refer to the decisional algorithms for difficult intubation, the obese
must be placed in the patient category in which a certain difficulty could
be predictable. This difficulty, often evaluated as severe, is associated
with a further disadvantage related to the kind of patient who is difficult
Anaesthesia in Bariatric Surgery
41

or impossible to ventilate by mask. Therefore, it might be prudent to pro-
ceed with OTI, with a colleague and equipment for difficult ventilation
and intubation, in order to apply all the alternative techniques appropriate
to difficult airways which are illustrated in decisional algorithms
approved by scientific societies.70
If the patient agrees, the possibility should be considered of intubat-
ing him whilst still conscious, using a local anaesthetic without sedation
and through the use of the flexible fibreoptic bronchoscope (FOB).
It has been useful, in many cases, for the anaesthetist to delicately
perform a laryngoscopic manoeuvre in order to create a working area
enough large to allow a good articulation of the distal tip of the FOB.
This procedure has been chosen in order to help those who use the endo-
scope when adopting an orotracheal approach. Furthermore, it is
important to remember that if we adopt a rhino-tracheal approach, one
must first go beyond the nasal duct with the FOB and then, when the
instrument is well placed in the trachea, to move past the choanae with
the tracheal tube, and to delicately move it through the FOB in the
trachea. This sequence of manoeuvres is necessary to avoid a nasal
haemorrhage caused by an attempt to move the tube too early. The nasal
haemorrhage would mask the laryngeal entrance making it difficult to see
both the glottis and the trachea with the scope and it may cause the
conditions for blood inhalation.
In connection with these problems, we recommend the use of a scope
expressly developed for this kind of manoeuvre and equipped with a large
aspiration canal. Such an instrument can quickly eliminate possible secre-
tions and, having thick distal end, is suitably resistant to the considerable
pressures to which it is often subject during these manoeuvres.
Other procedures using retrograde OTI must be avoided, as they con-
flict with the unfavourable anatomy of the obese patient. This anatomy is
characterized by abundant pre-tracheal panniculus adipose tissue in a
generally short or absent neck. This makes exploratory injections, in order
to safely introduce metallic mandrels, difficult if not impossible.
Therefore, in the case of anticipated difficult intubation, the
decision–action procedure is very linear if the patient is collaborative. On
the other hand, everything is much more difficult when the patient does
not collaborate or when they absolutely oppose the above mentioned
42
E. Pizzirani and G. Calcarella

manoeuvres. In that case, the specialist has to continue, as the eventual
operation could present urgent characteristics and it might not be possible
to delay. As it is impossible to operate using loco-regional anaesthesia, the
specialist must adopt a rapid induction followed by neuromuscular block
with depolarizing drug, carefully pre-oxygenating the patient and posi-
tioning them on the operating table in the best way.71
Correct pre-oxygenation, a precaution which is not always respected,
is fundamental to execute one or more attempts with OTI whilst main-
taining good levels of arterial O2 saturation. It is well known that the
necessary time to execute laryngoscopy and subsequent intubation is
directly proportional to the extent of difficulty in exposing the larynx and
inversely proportional to the ability of the performer of the manoeuvre.
A pre-oxygenation with high percentage of O2 in the mask is always
recommended since even an experienced anaesthetist needs 30–60
seconds to complete laryngoscopy, intubation and control over the success
of the manoeuvre. Pre-oxygenation can be obtained by asking the patient
to inhale deeply and very frequently for one minute, or with low current
volumes and low frequencies for 3–4 minutes. The comparison between
the two techniques (ventilation with current volume with O2 100 per cent
with a flux of 4 litres per minute for 5 minutes and ventilation with four
respiratory acts at high volumes with O2 100 per cent) has revealed that
both have been equally successful in raising the PaO2 up to values such as
300 mmHg. Furthermore, the time for desaturation (SaO2 < 90 per cent)
in the obese patient (with a weight not exceeding 45 kg compared to the
ideal weight) was 247 seconds, and 163 seconds in the super-obese by
oxygenation for 5 minutes.71
Before proceeding with laryngoscopy, it is necessary to correctly
position the head. A direct laryngoscopy, ending up with an intubation,
involves the alignment of the oral, pharyngeal and laryngeal axes so that
the passage from the incisors to the glottis is rectilinear.
If the head is simply placed on a horizontal plane (without any
support underneath), the oral, pharyngeal and laryngeal axes form a
C-shaped figure.
To obtain the alignment of the laryngeal axis with the pharyngeal axis,
the neck must be flexed on the thorax to an angle of about 30° raising the
head about 10 cm with supports placed under the occiput (shoulders
Anaesthesia in Bariatric Surgery
43

remaining on the operating table). To align the oral axis with both the pha-
ryngeal and the laryngeal ones, we have to extend the head over the neck
(extension at the level of the atlanto-occipital articulation) so that the
angle between the occipital-nasal axis would be 80–85 per cent with the
long axis of the neck and the facial plane at a 15° angle to the horizontal
plane. This position of head over neck is commonly called sniffing
position and it is a light flexion of neck on thorax and marked extension
of head on neck at the level of the atlanto-occipital articulation.72
To obtain a correct sniffing position in the obese, it is always useful
to raise the scapular area, shoulders and the base of neck with some sup-
ports, such as rolled sheets, elastic materials, etc., in order to allow an
appropriate flexion of neck on thorax and extension of head on neck. The
aim of the supports placed under scapula, shoulders and neck is to allow
the head to extend on the neck. The correct position must be evaluated
when viewed laterally because only this perspective gives us precise
information about the thoracic, neck, face and head axes. The complete
extension of head without the elevation of the occiput is contraindicated,
because this position increases the distance of the lips from the glottis,
makes the larynx turn to the front, places the oral axis on different levels
with both the pharyngeal and laryngeal ones and the teeth can cause lever
movements with the blade of laryngoscope.
It has also been observed in practice that it is necessary to search for
the optimal position of both head and neck before adopting anaesthesio-
logic induction and the subsequent laryngoscopy, since it is very difficult
to adopt them later after different unsuccessful attempts of OTI.
As to the pharmacological choices, in complex cases, when intuba-
tion is difficult and the optimal sniffing position is not reached, it seems
logical to adopt drugs which induce both anaesthesia and a neuromus-
cular blocking agent with a short lasting action (propofol,
succinylcholine or mivacurium) in order to allow a quick recovery of
consciousness and muscular strength suitable for spontaneous respira-
tion, in case of OTI failure.
In conclusion, what is the right approach towards a morbidly obese
patient who needs OTI?
Firstly it is always necessary to consider them a ‘difficult’ patient and,
therefore, to mentally and physically prepare oneself for possible
44
E. Pizzirani and G. Calcarella

problems. Therefore, a trolley is necessary, equipped with all the instru-
ments suitable for a patient who could undergo a difficult intubation.
The trolley should be equipped with the following instruments:
•
flexible fibreoptic bronchoscope and ventilation mask with nozzle for
the insertion of instruments;
•
faryngoscopic blades in different sizes;
•
introducers;
•
mandrils;
•
laryngeal mask;
•
combitube;
•
set for cricothyroidotomy;
•
system for Jet ventilation;
•
Bullard laryngoscope (optional).
It is important that each anaesthetist uses the FOB correctly and that every
effort is made to acquire the instruments and knowledge (theoretical and
practical courses) required to become a specialist.73,74
Positioning in the operating theatre
Positioning on a standard operating table can be difficult, so some operat-
ing theatres are equipped with two operating tables side by side which are
jointly able to support weights of up to 300 kg.48
The anaesthesiologic induction must be performed on the operating
table where the patient has been positioned when he was awake. In this
way the patient, before undergoing anaesthesia, can signal any discomfort
and avoid complications due to nervous compression in limbs and caused
by prolonged uncomfortable positions.
As we have already explained, to obtain an optimal position for the
intubation, the patient has to be in the sniffing position (light flexion of
neck on head and extension of head on neck).
As to intra-operative positions for particular surgical demands, it is
well-known that some of them, such as the Trendelenburg and lithotomic
positions are not well tolerated since they modify endo-abdominal pres-
sures, and movements alter the mechanical ventilatory parameters.
Anaesthesia in Bariatric Surgery
45

Prone positioning, instead, have to be considered. In a study per-
formed on obese (BMI > 30 kg/m2) patients75 undergoing surgery on a
herniated disc, it has been verified that the application of thoracic and
pelvic supports, used to keep abdominal mobility and to avoid the
pressure of the viscera on the diaphragm, improved the respiratory param-
eters. An increase in CFR may be observed due to both the reduced rising
of the diaphragm and/or to the re-opening of atelectasic areas.
Furthermore, pulmonary compliance, which decreases when in the supine
position, improves due to a mechanism of alveolar recruitment of areas
previously hypo-ventilated. On the other hand, the compliance of the tho-
racic wall was reduced, probably due to the action of the positioning
supports, whereas total resistance and its components were not modified.
Finally, the improvement of both CFR and static compliance (STC) turned
out to be consistent with an increase in oxygenation.75
The lateral position, allowing a greater diaphragmatic range, turns out
to be well tolerated as has been demonstrated by Brodsky et al. in the
mono-pulmonary anaesthesia with FiO2 corresponding to 1 in obese
patients.76
Monitoring
The general criteria used to determine what kind of monitoring should be
adopted depend on the type of surgical operation and the conditions from
which the patients are suffering. In the obese these criteria are not wholly
effective, because the general condition of these patients compels the spe-
cialist to scrupulously survey a wide range of parameters in order to have
the best opportunity of overcoming all the possible complications linked
to anaesthesia carried out on those with multiple organ and system defi-
ciencies. The standards of monitoring proposed by the scientific societies
can certainly fit the obese, but it is opportune to introduce a correction,
that is recommending the extensive application of monitoring standards
and the elimination of the habitual distinction between minor and major
interventions. Furthermore, the need to monitor the degree of neuromus-
cular block with Peripheral Nerve Stimulator (PNS) must be highlighted,
since the consequences of an over-dosage of neuromuscular blocking
agent could, during emergence from anaesthesia, be much worse than
46
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those seen in normal subjects. For the same reason we should not disre-
gard the monitoring of body temperature in the intra- and post-operative
phases, due to the well-known side effects on the patient’s haematosis.
General Anaesthesia
The induction of anaesthesia is a particularly delicate procedure, so that
some authors recommend the contemporaneous presence of more than
one anaesthetist in order to avoid possible difficulties represented by mask
ventilation and difficult OTI. Furthermore, as mentioned above, it is nec-
essary to have a trolley close at hand with all the necessary instruments
for solving problems of any sort.
In our personal case histories, which include about 2,000 patients with
as average BMI of 47 (range 37–72) we have observed a 3 per cent rate
of difficult intubation (defined as an OTI which needed more than three
laryngoscopies and non conventional procedures) while other studies
even record a prevalence of 13 per cent.
Pre-oxygenation is necessary, as in the obese patient an inverse cor-
relation between the degree of obesity and desaturation time has been
demonstrated. Pre-oxygenation allows us to make further improve-
ments to laryngoscopic manoeuvres without running the risk of early
desaturation.77
Drugs used for induction can be both thiopental and propofol,
whereas muscular relaxation is obtained with succinylcholine
(1.2–1.5 mg/kg of IBW). We must always remember that the obese can
have a pseudocholinesterase activity which is higher than normal41 and
which can determine a rapid metabolization of the drug.
Should the laryngoscopic vision be reduced (2nd degree: arytenoid
cartilages; 3rd degree: epiglottis; 4th degree: soft palate) it would be
useful to manipulate the larynx by pushing it backwards, upwards, right
and in a posterior position (BURP: Back–Up–Right–Posterior). This
manoeuvre generally improves laryngoscopic vision by at least one
degree.
With respect to maintenance of anaesthesia, the superiority of one
determined anaesthesiologic technique over another has not been demon-
strated, but it seems that a balanced anaesthesia, whenever possible, is
Anaesthesia in Bariatric Surgery
47

preferable. This is because it allows a better dosage of single drugs, a greater
concentration of O2, all the while reducing the concentration of volatile
anaesthetics. It also results in an earlier extubation, reduces post-operative
complications and gives a more satisfactory post-operative analgesia.78
Among opiates remifentanil is widely used for its pharmacokinetic
characteristics, which make it the first drug of choice whenever a rapid
post-operative recovery is needed.
As to neuromuscular blocking agents, one tends towards vecuronium
and cisatracurium, favouring the latter due to its elimination (not organ
dependent), and which even in the case of prolonged operations is not
particularly affected by the numerous organ pathologies which can afflict
the obese.
Mechanical ventilation is practised using an initial current volume of
about 7–8 ml/kg of IBW which, associated with the reduced compliance
of the thoracic wall and the rising of the diaphragm due to an increase in
the intra-abdominal pressure, can cause the development of high peak
pressures.
Premature hypoxia, observable in the first phases of anaesthesia, is
linked to the reduced CFR, as a reduction in this parameter of about 50 per
cent already occurs in the phase of anaesthesiologic induction (from 2.2 l
to 1 l). It has been demonstrated that both manual hyper-inflation58 and
application of PEEP < 10–15 cm H2O increase the CFR and improve
oxygenation.22
Should decreases in SaO2 occur, ventilation techniques which involve
manoeuvres of increasing recruitment and the subsequent application of
high PEEP, can also be useful. Pulmonary recruitment can be particularly
valuable during laparoscopic operations where, due to a further increase
in the intra-abdominal pressure, the rising of the diaphragm can be more
marked. These manoeuvres must not result in exceeding determined
values of peak pressure (not over 50 cm H2O) and they must be conducted
under strict haemodynamic monitoring.
The risk of intra-operative hypoxia can involve the use of elevated
FiO2 especially in patients with serious pulmonary and/or cardiovascular
pathologies, and this can affect the choice of the inhaled gaseous mixture.
Therefore it would be preferable to use a mix of air and O2 with hypnosis
maintained by anaesthetic vapours or intravenous drugs.40
48
E. Pizzirani and G. Calcarella

During surgery it is possible, thanks to the aid of end tidal CO2
(ETCO2), analysis of arterial O2 saturation and blood–gas analysis, to
adjust the current volume and the extrinsic PEEP to avoid the
hypocapnic conditions (PaCO2 < 30 mmHg) responsible for an
increase in shunt (as a result of the vasodilatation induced) and a
reduction of the venous return. Moreover mere ETCO2 is not a suffi-
cient parameter for good ventilation because in the obese the
difference between PaCO2 and PetCO2 is very marked due to the
increase in the alveolar dead space.
We have little information on the haemodynamic alterations which
occur during general anaesthesia in the obese. In a prospective study on
patients subject to major abdominal surgery, a reduced correlation
between LVSW and PAWP has been highlighted. This is an index of
reduced left ventricular contractility, both during intubation and in the
post-operative period, with consequent reduction in the cardiac index of
20–30 per cent.31
A recent study by El-Dawlatly79 shows a significant reduction in the
cardiac index of obese patients compared with patients of normal body
weight subject to laparoscopic surgery. However the meaning of this alter-
ation is not clear.
Extubation must be performed to achieve a complete resolution of the
muscular blockage. It should be measured with a neuro-stimulator, and
the presence of an adequate cough reflex could be considered appropriate.
It may be prudent to suggest the use of a tube exchanger, in case it is
necessary to facilitate a rapid reintubation, and to prevent the inhalation
of the gastric contents.
Patients with positive anamnesis linked to respiratory and/or cardio-
vascular disease, serious endocrinopathy and uncontrollable hypertension
are expected to be admitted to intensive care. This is also expected for
patients subject to major abdominal or thoracic operations. It is possible
that an incomplete resolution of neuromuscular block, a state of main-
tained post-anaesthetic sedation or a particularly intense post-operative
shivering can all compromise post-operative recovery, even after simple
operations. In these cases therefore it is advisable to be very cautious and
to monitor the patients in intensive care units until post-operative recov-
ery is complete.
Anaesthesia in Bariatric Surgery
49

Loco-Regional Anaesthesia
Loco-regional anaesthesia, when possible, is recommended by the major-
ity of authors. The difficulties in its execution are essentially linked to the
loss of the traditional anatomic landmarks. Epidural or subarachnoidal
anaesthesia can be less difficult than expected since the median dorsal line
presents a minor layer of fat compared to the lateral zones. With both tech-
niques, epidural or subarachnoidal needles longer than 10 cm make
procedures particularly difficult. To carry out the procedure it is preferable
to have the patient sit down, the epidural space then being more easily
identifiable through the loss of resistance technique.
A subarachnoidal block is technically less difficult than an epidural
block, but its extension is often unpredictable, the onset is slower and
latency time is longer, even over 30 minutes for its completion.58
The major cephalic diffusion of the anaesthetic occurring after the
block is linked to the increase in the adipose tissue, with consequent
reduced dimensions of the subarachnoid space. It has been observed that
blocks extending to levels higher than T5 can cause serious respiratory
repercussions in obese patients with pre-existing pulmonary diseases and
also severe vascular collapses due to sympathetic block. This can be par-
tially compensated for by preventive infusion of liquids. With the epidural
technique, doses of local anaesthetic necessary for surgical anaesthesia
are generally reduced by 20–25 per cent. This is due to the reduced vol-
ume in the epidural space in consequence of the conspicuous presence of
adipose tissue and the increase in the haematic venous content shifted by
the vena cava due to the increase in abdominal pressure. The difficulties
in executing peripheral regional blocks can be limited by using isolated
needles of the appropriate length and a neuro-stimulator80 which naturally
amplifies the sensibility of the operator and limits the consumption of
drug. Intra-venous anaesthesia (Bier block) is contra-indicated by the fre-
quent diffusion of the anaesthetic which, even if used in doses related to
IBW, can cause serious episodes of cardiac and neurological toxicity.81
When these loco-regional techniques are adopted, it is desirable that
the patient has adequate monitoring, oxygen therapy and a very mild seda-
tion in order not to alter a very labile equilibrium. In these cases all the
necessary instruments must be available to deal with probable respiratory
50
E. Pizzirani and G. Calcarella

and/or cardiovascular complications, as well as all that is necessary to
convert this technique into a general anaesthesia.
Morbid obesity during pregnancy is frequently associated with dia-
betes, hypertension, pre-eclampsia, high incidence of caesarean section
and premature births affected by macrosomia. In these patients, in addi-
tion to the technical problems linked to obesity and its related pathologies,
there are the difficulties related to the need to operate in a state of emer-
gency.82 Such operations often include respiratory complications resulting
from a difficult intubation and more frequently than in other situations, it
is necessary to follow a decisional algorithm.
Post-Operative Treatment
This focuses on:
•
prevention and treatment of the probable cardiocirculatory, respira-
tory and thromboembolic complications;
•
endocrine disorders or imbalances;
•
inadequate control of post-operative pain.
In the post-operative phase, respiratory complications are three times
higher in the obese. Body weight, BMI or tests of respiratory pre-
operative functionality do not seem to correlate to the occurrence of such
complications. What is more frequently observed is respiratory insuffi-
ciency accompanied by more or less marked degrees of hypoxia. These
are natural consequences of a reduction in CFR and a high incidence of
basal atelectasis which are produced in the first phases of surgery under
general anaesthetic.
Two particularly effective techniques in preventing the development
of atelectasic areas have been described: ventilation at two different pres-
sures (BIPAP) and ventilation with continuous positive non-invasive83
pressure (CPAP). Each technique must be carried out with a scrupulous
monitoring of the vital parameters (ECG, FC, SaO2, PA, FR) and signs
such as muscular effort, cough efficiency, level of consciousness of the
patient, the appearance of bronchial obstruction and development of
infection.
Anaesthesia in Bariatric Surgery
51

Patients with OSA can be subject to serious obstructions of the upper
airways. Some post-operative deaths have in the past been attributed
to pulmonary embolism, seemingly caused by acute and severe post-
operative hypoxia.
Respiratory insufficiency more frequently appears in the first three
days post-operatively and can last for 4–6 days. The need for mechani-
cal ventilatory support is fairly rare and is necessary only for anxious
and non-collaborative patients, the over 50s, cardiopathic patients and
those who suffer pre-operatively from hypercapnea and who develop
fever in the post-operative period when they undergo major surgical
operations.
Different measures can be taken to reduce the incidence of these kinds
of complications:
•
keep the patient in a semi-sitting position (30–45°) for several days;
•
early mobilization;
•
active respiratory physiokinesitherapy;
•
optimization of the post-operative analgesia.78
Cardiomyopathy linked to reduced left ventricular contractility, observed
in the immediate post-operative phase, contributes to increased post-
operative mortality rates. Pulmonary embolic complications, which
according to some studies are often fatal, are observed post-operatively in
5–12 per cent of obese patients84,85 and are promoted by the frequency of
deep vein thrombosis resulting from polycythaemia, increased haematic
volume, reduced fibrinolytic activity and stasis of vena cava secondary to
the increased abdominal pressure and prolonged immobilization.
On this subject, a recent study of the coagulation function in pre-
operative morbidly obese patients has revealed the presence of
anomalies such as accelerated formation of fibrin, activation of the
blood platelet function and of interaction between fibrinogen and
blood platelets.
These elements, correlated with the pre-operative presence of an
increased concentration of fibrinogen and the factor inhibiting the activa-
tion of plasminogen (released by the adipose tissue), confirm the tendency
to hyper-coagulation present in these patients.86
52
E. Pizzirani and G. Calcarella

This condition could also explain the increased frequency of thrombo-
embolic complications connected to the insertion of canula in central
veins observed by some authors.87
As to the percentage of post-operative mortality, opinions differ, but
there is consensus on the evidence of increased morbidity due to respira-
tory, embolic and infective complications.88 What is more, with the
exception of an improvement in PaO2 as a result of slimming, no study has
demonstrated that pre-operative weight loss reduces the frequency of
morbidity and/or post-operative mortality.
Conclusions
Different anaesthesiologic techniques have been recommended for the
obese patient, but none of them have demonstrated real advantages over
others. In general both the anaesthetist’s knowledge and experience in
avoiding complications are determining factors in improving the outcome
of surgery. What we can conclude from the above-mentioned problems is
that these kinds of patients require the greatest level of concentration on
the part of the anaesthesiologists, even when the procedure is brief and
straightforward. All these procedures are more complex (both from the
point of view of human effort and the equipment required) than those
required for patients of normal body weight.
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41. Bentley, J.B., Bond, J.D., Vaughan, R.W. et al. (1982). Weight, pseudochol-
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43. Egan, T.D., Huizinga, B., Gupta S.K. et al. (1998). Remiphentanil pharma-
cokinetics in obese versus lean patients. Anesthesiology 89: 562–573.
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46. Taivainen, T., Tuominen, M., Rosenberg, P.H. (1990). Influence of obesity
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49. Van Itallie, T.B. (1994). Worldwide epidemiology of obesity. Pharma-
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53. Frink, E.J. Jr, Brown, E.A., Morgan, S. et al. (1993). Plasma inorganic fluo-
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54. Higuchi, H., Satoh, A., Kanno, M. (1993). Endoserum inorganic fluoride
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55. Connolly, L.A. (1991). Anesthetic management of obstructive sleep apnea
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56. Lee, J.J., Larson, R.M., Buckley, J.J. et al. (1982). Airway maintenance in
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58. Hodgkinson, R., Hussein, F.J. (1980). Obesity and the spread of analgesia
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59. Cooper, J.R., Brodsky, J.B. (1987). Anesthetic management of the morbidly
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60. McCulloch, W.J., Littlewood, D.G. (1986). Influence of obesity on
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61. Alpert, M.A., Singh, A., Terry, B.E. et al. (1989). Effect of exercise on left
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62. Paul, D.R., Hoyt, J.L., Boutros, A.R. (1976). Cardiovascular and respiratory
changes in response to change in posture in the obese. Anesthesiology 45: 73.
63. Ryan, C.F., Lovel, L. (1996). Mechanical properties of the velopharynx in
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64. Jeffers, L.A. (1996). Anesthetic considerations for the new antiobesity
medications. AANA J 64(6): 541–544.
65. Damia, G., Mascheroni, D., Croci, M. et al. (1988). Perioperative changes in
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66. Brodsky, J.B. (1986). Anesthetic management of the morbidly obese patient.
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67. Robertson, I.K., Eltringam, R.J. (1985). Anaesthetic management of the
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70. Benumof, J.L. (2004). Obesity, sleep apnea, the airway and anesthesia. Curr
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78. Rawal, N., Sjostrand, U., Christofferson, E. et al. (1984). Comparison of
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Chapter 3
Intragastric Balloon (BIB®) in the
Management of Morbid Obesity Disease
Alfredo Genco, Roberta Maselli and Nicola Basso
Introduction
The natural history of patients suffering from pathological obesity is
chequered with the repeated failures of dietary, behavioural and pharma-
ceutical therapies. Nowadays, only 6 per cent of the overweight patients
who rely on diet treatment alone find an effective and radical solution to
their serious problems.
The indications inherent to surgical treatment are, on the other hand,
strictly specific, limited and even today, far from acceptable even to
severely overweight patients. Bariatric surgery has, moreover, been
shown to lead to a greater incidence of intra- and post-operative compli-
cations, directly correlated to the numerous diseases resulting from obesity.1
It is often difficult to intubate and mechanically ventilate super-obese
patients.2 Studies have demonstrated that the probability of problematic
intubation is proportionate to the circumference of the patient’s neck,
ranging from 5 per cent per 40 cm circumference, to 35 per cent per 60 cm
circumference.1 They have also shown that, because body weight is the
chief factor underlying the determination of the arterial oxygenation
tension in anaesthetized, overweight patients, there is less than 30 per cent
respiratory compliance compared to normal-weight patients.3 Most bariatric
operations are now carried out laparoscopically. Technical-surgical and
systemic problems induced by the pneumoperitoneum are far more
61

62
A. Genco et al.
evident than in other types of patients.1 The presence of a considerable
amount of intestinal fat leads to numerous technical difficulties: the oper-
ating area is often badly visualized, increased omental fat frequently
obstructs visualization of the stomach, a ‘fatty liver’ cannot easily be
mobilized by the retractors,4 leading to a high rate of conversion to open
surgery.5
As early as 1986 Pasulka et al. demonstrated how a modest pre-
operative weight loss (10–20 per cent) reduced surgical complications,6
whether anaesthesia-based or not, resulting from bariatric surgery.
Consequently, over the last few years, the interest of ‘insiders’ oper-
ating in the sector has turned to remedies able to help patients to maintain
restrictive and long-term diet programmes. These programmes aim at
making dietary therapy more ‘aggressive’ and effective, thus leading to
greater control of the co-morbidities in view of radical surgical treatment.
One of these remedies is the intragastric balloon.
The concept underlying the use of an intragastric balloon in the treat-
ment of obesity first saw the light in 1921 when Davies observed that
patients with bezoars (partially digested agglomerates of hairs or veg-
etable fibres called, respectively, hair-balls or food-balls (tricobezioars or
phytobezoars), often complained of post-prandial fullness, nausea and
vomiting. This led to the idea of contriving a device which would imitate
an intragastric bezoar by partially filling the stomach.7
The first intragastric balloon to be marketed was the Garren-Edwards
Gastric Bubble (GEGB, American-Edwards Laboratories, Irvine, CA,
USA), approved in 1985 by the Food and Drug Administration as a device
co-adjuvant to diet and behaviour-modification treatments. The GEGB
was a cylindrical, polyurethane contrivance, with a self-filling valve at
one end through which a removable catheter for air inflation was inserted.
It was placed inside the stomach by means of a dedicated introducer, then
inflated with 220 ml of air. Removal was carried out endoscopically after
puncturing the bubble (Fig. 1).
The device was used in the USA up to 1988, with over 25,000 place-
ments. Between 1987 and 1989 numerous scientific studies devoted to it
were published, expressing the unanimous conclusion that the GEGB was
no more successful in achieving weight loss than dieting alone or modified
alimentary behaviour.8–14 The complications reported included: gastric

erosion (26 per cent), gastric ulcers (14 per cent), intestinal obstruction
(2 per cent), Mallory–Weiss syndrome (11 per cent), oesophageal tears
(1 per cent).12 Due to the considerable collateral effects and lack of data
supporting its efficacy, GEGB is no longer used and is now unavailable
commercially.15,16
After the GEGB numerous modified intragastric balloons were intro-
duced and evaluated in minor scientific studies. GEGB’s lack of safety
and efficacy was attributed, by some critics, to the low air-volume inflated
into the balloon and to the material used in its fabrication. Among the var-
ious balloons presented, the ‘Ballobes intragastric balloon’ (DOT ApS,
Rodovre, Denmark) deserves some attention (Fig. 2).
Intragastric Balloon in the Management of Morbid Obesity Disease
63
Figure 1.
Garren-Edwards balloon.
Figure 2.
Ballobes intragastric balloon.

This was inflated with about 475 ml of air but, in this case too, the rel-
evant studies demonstrated no additional advantages of the balloon over
dieting, physical exercise and modified eating habits. Despite the varia-
tions adopted, with respect to the original concept of a space-occupying,
intragastric bubble, none of the devices conceived seemed to be effective
and complication-free. For this reason they were, and are, no longer used
in clinical practice.
With the introduction of the BioEnterics® Intragastric Balloon (BIB®,
Allergan Inc., Irvine, CA, USA), a new chapter in the history of intragas-
tric balloons is being written (Fig. 3).
BIB®: Characteristics and differences compared
with the 1980s bubbles
In March 1987 a team of experts at Tarpon Springs (Florida, USA)
defined the specifications of the ideal intragastric balloon (Table 1).
Subsequently the BIB® intragastric balloon was launched on the market.
The BIB® system is made up of a soft, transparent, silicone balloon
connected, by means of a radiopaque valve, to a ‘placement’ catheter
with a 6.5 mm external diameter, also made of soft silicone. This
catheter is stiffened by a metal guide-wire, which facilitates the move-
ment of the balloon down the oesophagus during placement and is
64
A. Genco et al.
Figure 3.
Intragastric Balloon BIB®.

connected to the valve, at both ends, by a ‘Y-shaped’ loop connected,
in its turn, to the filling system. The fill volume advised is 500–700 ml
of physiological solution and removal after 180 days is recommended.
The addition of 10 ml of viable staining (methylene blue) to the physi-
ological solution will colour the urine blue should the intragastric
balloon break.17
Three fundamental factors clearly distinguish the BIB® intragastric
balloon from the 1980s bubbles:
•
the liquid content which makes it definitely more effective (greater
sense of repletion);
•
the ‘self-sealing’ radiopaque valve which increases safety because
it gives the BIB® freedom of movement inside the gastric cavity
rendering breakage before 180 days extremely rare;
•
the spherical form and silicone structure which render the complica-
tion of ulcers extremely rare.
How it works
The efficacy of the BIB® in inducing weight loss is due not to a placebo
effect but to the characteristics which make it effective ‘in itself’.18 How
it actually works is only partially known and chiefly depends on the
characteristics of the device:
•
Its weight (the BIB® is filled with 500–700 ml of liquid), which mas-
sively stimulates the baroceptors located at the gastric wall level.
These, through the brain-gut axis, stimulate the satiety centre located
Intragastric Balloon in the Management of Morbid Obesity Disease
65
Table 1.
Ideal intragastric balloon characteristics.
Efficacy
Variable volume
Spherical shape
Soft surface
Filled with liquid
Radiopaque valve

at hypothalamic level; this mechanism is particularly active in the first
two–three months post placement and diminishes during the follow-
ing months.
•
Delayed gastric emptying: an ultrasonographic study on gastric emp-
tying pre- and post-placement of the BIB® was carried out at our
institution. This highlighted the fact that in patients without the bal-
loon, food could already be visualized by ultrasound in the antrum 32
minutes ± 12 minutes after the consumption of a solid, 800 Kcal meal.
Thirty days after BIB® placement in the same patients, this study only
visualized food in the antrum after 300 minutes ± 23 minutes. These
data are supported in a recent study by Torres-Barrera et al. who
demonstrated a reduced electric gastric activity deriving from intra-
gastric balloon placement.19
•
Reduction of unoccupied gastric volume by about 750 cm3 due to the
presence of the device.
•
Discomfort: this term means the overall disorders (nausea, precocious
sense of satiety, vomiting, epigastric pain) suffered during the first
24–30 hours post-placement and which may reappear during the six-
month treatment, above all if the patient fails to adhere to the
prescribed dietary regime.
•
Hormonal mechanisms: in our experience during treatment with the
BIB® in the first three months a significant increase in the plasmatic
ghrelin levels was observed. This was followed by a gradual reduction
until the basal levels were reached after removal, despite the persist-
ence of the weight-loss. Other studies show hormonal variations in
patients with the BIB®. Mion et al.20 show that during BIB® treatment
plasma ghrelin levels were significantly decreased (–3.8 to –20.7 ng/ml),
despite concomitant weight loss. Weight reduction was significantly
correlated to the ghrelin variations (0.212–0.885 ng/ml). We already
know that the ghrelin is correlated to weight loss, but we still do not
know exactly how.
Indications
The BIB® system is indicated for temporary use associated with a specific
slimming programme using diet treatment under direct medical control, in
66
A. Genco et al.

patients with a history of obesity (at least five years), after numerous
failures of dietary treatment only.
Present indications suggest BIB® placement in patients with:
•
< 35 BMI if there are concurrent obese-related co-morbidities (e.g.
cardiovascular, orthopaedic, metabolic etc.) whose resolution or
improvement require mandatory weight loss;
•
> 35 BMI, within the framework of anti-obesity treatment where the
balloon plays a pre-surgery role in patients with co-morbidities, before
any other type of surgery (orthopaedic, cardiac etc.), or in patients
who refuse surgery;
•
‘BIB® Test’ to evaluate capacity to comply with a pre-established diet
programme, in patients who are candidates for restrictive-type surgery
and whose eating behaviour is difficult to pinpoint.
At the moment there are no specific limitations as regards age. The device
can, therefore, also be used for children.
Contraindications
Placement of the BIB® is contraindicated, at present, in:
•
voluminous hiatal hernia (>5 cm);
•
oesophagitis > Grade II;
•
duodenal ulcer;
•
potential bleeding conditions of the upper gastrointestinal tract;
•
outcomes of prior, major surgical operations on the gastrointestinal
tract and/or certified adhesion syndrome;
•
neoplasias;
•
patients receiving chronic treatment with gastric irritants or anti-
coagulants;
•
patients with major or non-collaborative psychiatric disorders;
•
alcohol or drug dependent patients;
•
certified pregnancy;
•
all inflammatory pathologies of the gastrointestinal tract (e.g. Crohn’s
disease, etc.).
Intragastric Balloon in the Management of Morbid Obesity Disease
67

Work up
All patients undergo the following clinical procedures:
•
complete haemato-chemical tests;
•
ECG and cardiologic video;
•
diagnostic oesophago–gastro–duodenoscopy with HP analysis;
•
endocrinologic/dietologic examination to exclude endocrine-based
obesity;
•
psychiatric examination to exclude psychiatric illness and to ascer-
tain, if they exist, the type of the eating disorders (e.g. ‘sweet eating’,
‘binge eating’ etc.).
A chest X-ray, respiratory function tests and anaesthesiologic examination
are required for super-obese patients with breathing difficulties. All the
patients, after receiving accurate and exhaustive information, have to give
their written consent.
Placement and removal technique
BIB® placement and removal can be performed in conscious sedation with
Diazepam or Midazolam (80 per cent), in unconscious sedation with
Propofol (15 per cent) or with orotracheal intubation (5 per cent). During
placement the patient is in left lateral decubitus and a diagnostic oesophago–
gastro–duodenoscopy is performed. The balloon is then positioned with
the valve under the cardia and is filled, under endoscopic vision, with
500–700 ml of physiological solution and 10 ml vital staining solution
(methylene blue). The connection catheter is removed and the valve checked
for possible leaks. The mean duration of the procedure is 12 minutes.
Methylene blue is used for early identification of balloon rupture or
valve leaks: should the intragastric balloon break, the solution will be
absorbed and will colour the urine blue. For this reason it is important to
sensitize the patient to ongoing urine observation before discharge from
the hospital.
A diligent anamnesis is essential to exclude the presence of glucose-6-
phosphate-dehydrogenase (G-6-PDH) deficit. Patients with this disease,
68
A. Genco et al.

like those afflicted with ‘favism’ could, in fact, suffer a haemolysis crisis
due to the methylene blue. In these cases methylene blue cannot be used and
possible balloon rupture or valve leaks can be ascertained ecographically.
BIB® removal is carried out after six months. Due to the delayed gas-
tric emptying achieved with the balloon, the removal procedure should be
preceded by a 72 hour, no-‘roughage’ diet and by a 24 hour semi-liquid
diet (yoghurt, mashed potatoes, puréed vegetables). It is very important
that the patient respect this diet in order to avoid ‘ab ingestis’, chiefly
when the procedure is performed in unconscious sedation. In these cases
the patient should never lose the cough reflex.
The procedure foresees an oesophago–gastro–duodenoscopy to facil-
itate identification of the balloon and its subsequent deflation with a
specific device. The BIB® is removed with a dedicated ‘grasper’ when
completely deflated. Stomach observation is necessary to exclude possi-
ble mucosal lesions.
BIB® placement can be performed on in-patients, out-patients and in
day hospitals; in Italy, to be able to claim refunding from the National
Health Service, it is usually carried out on in-patients with at least two
days’ hospitalization. When it is performed on out-patients or in day
hospitals, the patient must always be properly informed as to the adverse
symptoms which may arise. It is essential, moreover, that close, ongoing
follow-up be carried out to facilitate diagnosis and to be able to treat
complications such as hydro-electrolitic imbalance or gastric dilation.
Post-placement pharmacological treatment
Due to the secondary effects deriving from the presence of the BIB®
(nausea, regurgitation or vomiting, cramp-like epigastric pains) and from the
almost total impossibility of eating during the first 24–36 hours, all patients
must receive support treatment consisting in the infusion of electrolytic
solutions, proton pump inhibitors, antispasmodic and antiemetic drugs.
Post-placement diet
On the first day the patient receives a liquid diet only. From the second
and up to the sixth or seventh day a semi-liquid diet (yoghurt, mashed
Intragastric Balloon in the Management of Morbid Obesity Disease
69

potatoes, puréed vegetables) is followed. The dietetic regime to be asso-
ciated with the intragastric procedure has not yet been fully standardized
but, as of the seventh or eighth day our patients receive a diet programme,
prepared by the nutritionists. This foresees a daily intake of about
1000–1200 Kcal (68 g protein, 18 g lipids, 146 g glucids — at least 1 g
protein/kg ideal weight), consumed over three main meals and two
snacks. For the first three months, moreover, a multi-vitamin supplement
is added. This dietetic regime is maintained until removal of the BIB®.
Our experience shows that the daily consumption of a high volume of
vegetables is inadvisable because they are difficult to digest. They clog up
the gastric cavity and cause vomiting. It is therefore advisable to prescribe
vegetables in soup form.
Follow-up
All patients are contacted by phone every day for the first seven days. On
the eighth day they undergo an in-office clinical-nutritional examination.
During the remaining period the patient undergoes every two weeks, alter-
natively, a clinical-nutritional examination and an evaluation carried out
by one of the team of physicians that performed the procedure. The psy-
chological assistance for the entire treatment (six months) is performed
only if requested during the first pre-treatment work-up meeting, by the
patients or by the psychologists themselves.
When there are signs (e.g. blue urine) or symptoms indicating a pos-
sible complication, an immediate clinical evaluation of the patient, and a
possible oesophago–gastro–duodenoscopy, is essential. Decubital ulcers
or gastrectasia indicate the need to remove the BIB®.
Before discharge the patient is made aware of the importance of
optimum hydration and of ongoing urine checks, in order to diagnose
in time the premature rupture of the BIB® or a possible valve leak. All
the patients are, obviously, informed of the increased chance of balloon
rupture if it remains in the gastric cavity for longer than the prescribed
six months.
At the end of the sixth month the BIB® will, in any case, be removed.
The following alternatives are then evaluated: (a) starting the patient of on
a ‘maintenance’ diet programme; (b) subjecting him/her to the consensual
70
A. Genco et al.

placement of a second BIB® (multiple treatment); (c) performing the
previously planned bariatric surgery.
Results
Secondary post-placement effects
In our experience the secondary post-placement effects were: nausea for
24–36 hours in 87 per cent of the patients; vomiting (a mean two episodes)
in 51 per cent; slight epigastralgia in 61 per cent, regressed with anti-
spasmodic drugs; increased intestinal meteorism in 36 per cent; diarrhoea
(5–6 episodes/day) in 5 per cent; and halitosis in 12 per cent (Table 2).
Weight loss
From March 1998 to November 2006 our case histories recorded 640
placements of BIB® in 583 patients (181 male/402 female). The mean
age was 37.5 (19–69); mean BMI 42.7 (30.7–56.5); mean EW percent-
age 68.3 (43–117.6). The incidence of intra-operation complications
during placement and removal was nil. At the end of the treatment the
patients presented: BMI 34.8, EWL 34.4 per cent (Table 3). These results
Intragastric Balloon in the Management of Morbid Obesity Disease
71
Table 2.
BIB® post placement symptom.
Nausea
87%
Vomiting
51%
Epigastralgia
61%
Meteorism
36%
Diarrhoea
5%
Halitosis
12%
Table 3.
Results of 583 patients that have undergone BIB placement.
BMI
EW % — EWL %
BIB placement
42.7
68.3 EW %
BIB removal
34.8
35.4 EWL %

can be superimposed on those reported by the Italian LAP-BAND® and
BIB® group (GILB) relevant to 2,515 cases with a mean weight-loss of
9.0 BMI and 33.9 per cent EWL21 (Table 4). As regards the modality of
the weight loss, about 60 per cent occurs within the first 6–8 weeks, then
evens out over the remaining months (Fig. 4). The best results are
obtained in hyperphagic patients without specific modification of ali-
mentary behaviour. Eating disorders influence the quantity and modality
of the weight loss. In patients suffering bulimic crises the results are dis-
couraging when evaluated with respect to weight loss; it must be
emphasized, however, that as regards to the bulimic patients group, some
of them reduced the number of their crises considerably (Fig. 5) from a
mean of 8–10 a week to 1–2 a month. This condition is, however, limited
to the BIB® treatment period, because after removal there is a gradual
renewal of the eating disorder.
72
A. Genco et al.
Table 4.
GILB results of 2,515 patients.
BMI
EW % — EWL %
BIB placement
44.4
59.5 EW %
BIB removal
35.4
33.9 EWL %
0
10
20
30
40
50
1
2
4
6
8
10
12
14
16
18
20
22
24
Weeks
%
Figure 4.
Weight loss/weeks.

Other important results derive from our study which compares weight
loss achieved by BIB® combined with dietary instructions versus a
tapered diet therapy at six months, when the balloon was removed, and at
eighteen months, twelve months after BIB® removal. The experimental
group (BIB® + diet) consisted in 122 obese patients (81 females, 41 males)
mean age 37.7 ± 11 years and mean BMI 41.8 ± 6.8; the control group
(diet alone) comprised 128 patients (84 females, 44 males) mean age 39 ±
12.3 years and mean BMI 42.0 ± 6.
Weight loss was significantly higher in patients treated with BIB®
when compared to a matched group of patients treated by diet alone
(weight loss 16.2 versus 6.6 kg, BMI decrease 5.7 versus 2.5 kg/m2) at six
months. The difference persisted to a lesser degree but was still significant
at follow-up (twelve months), both groups showing a tendency to regain
weight at the follow-up (twelve months) after the treatment. In the patients
treated with BIB® the average weight loss from baseline was reduced to
11.2 kg and the BMI loss to 3.5 kg/m2, while in the control group, treated
by diet, weight loss from baseline was 5.5 kg and BMI loss was 2.0 kg/m2.
These results demonstrate that intragastric balloon combined with
dietary instructions induces significantly higher weight loss then simple
dietary therapy in the first six months of treatment and persists at twelve
months of follow-up.22
Intragastric Balloon in the Management of Morbid Obesity Disease
73
0
2
4
6
8
10
12
14
months
B I B
RE
M
O
V
AL
Figure 5.
Bulimic crisis pre and post BIB®.

Long-term results
It is difficult to consider the long-term efficacy of a device such as the
intragastric balloon, created for temporary treatment. There are actually
no data in the literature concerning long-term BIB® results. The longest
follow-up reported (Melissas et al.23) is 1.5 years (range 6–30) when:
100/140 patients (71.4 per cent) lost ≥25 per cent of their EW on
balloon extraction and were categorized as successes, while 40 patients
(28.6 per cent) did not achieve that weight loss and were categorized as
failures of the method. During the follow-up period, 44 of the originally
successful patients (31.4 per cent) regained weight and were categorized
as recurrences, while the remaining 56 patients (40 per cent) maintained
their EWL of ≥25 per cent and were considered ‘long-term successes’.
In a prospective study carried out on a 100-patient sample, Herve et al.24
report that:
at BIB® removal mean weight loss was 12.0 kg. Mean EWL per cent was
39.8. 12 months after removal of the BIB®, mean weight loss was 8.6 kg
and mean EWL was 26.8 per cent for the group as a whole.
The Brazilian experience, performed on a 483 patients between 2000 and
2004, indicates that after a six-month follow-up subjects showed signifi-
cant reductions in weight (15.2 ± 10.5 kg), EWL percentage (48.3 ± 28.1),
and BMI (–5.3 ± 3.4 kg/m2). The 85 patients who completed one year
follow-up after BIB® placement (six months after BIB® removal), (34 per
cent of the 250 patients who completed 1 year after BIB® placement),
maintained a substantial weight reduction, even if their one-year percent-
age EWL (50.9 ± 28.8) was significantly lower than their six-month
percentage EWL (57.4 ± 26.4 per cent). However, 17 patients who were
followed up two years after BIB® placement (11 per cent of the
158 patients who completed two years follow-up after BIB® placement)
showed two-year percentage EWL 56.9 ± 36.5, which was not signifi-
cantly different from their six-month percentage EWL of 66.1 ± 28.0.25
This experience also shows the results relating to adolescents: 21 adolescents
74
A. Genco et al.

(age < 18 years) changed from a pre-treatment BMI of 36.5 ± 8.4 to a six-
month BMI of 31.5 ± 9.1 (BMI reduction –5.0 ± 3.6), with a mean
percentage EWL of 57.4 ± 37.0. The five adolescents who completed a
one-year follow-up maintained a mean percentage EWL of 46.5 ± 30.4, a
result statistically not different from their six-month percentage EWL of
49.2 ± 27.3.
Within the framework of our experience26 from our database pertinent
to obese patients undergoing the BIB® from March 1998 to July 2006 (total
number of patients 613), we selected those having at least a 48 months
post-removal follow-up (n = 145). We excluded patients who had under-
gone bariatric surgery after BIB® removal (n = 52) and who had a
sequential BIB® placement or other non-surgical weight loss treatment
(n = 30). The remaining patients (n = 45) were contacted and submitted to
clinical evaluation. Weight fluctuations and any further interventional
therapy requested by the patients after balloon removal were recorded.
Excess weight loss (EWL) ≥25 per cent when the BIB® was removed was
considered a success. Thirty patients (69 per cent) lost ≥25 per cent
(range 25.0–69.0) of their excess weight on balloon removal and were
classified as ‘successes’, while 15 patients (31 per cent) lost from 0 to
21.0 per cent of their excess weight and were categorized as ‘failures’. At
60 months follow-up (60 months ± 21.47; range 48–96) 30 per cent (9/30)
of the ‘success’ group had an EWL percentage of ≥25 and were catego-
rized as ‘long term successes’; whereas 70 per cent (21/30) of them had
an EWL percentage of <25 and were categorized as ‘long term failures’.
To individualize possible predictive factors in long-term success, we eval-
uated the association between follow-up results and three factors: initial
BMI (<35, 35–40, 40–50, >50), pre-BIB® age (>35 years, <35 years),
and sex (male/female). A statistical analysis was done on the investigated
predictive factors that have confirmed the associations: female gender,
age <35 years and initial BMI from 35 to 40 are long-term success pre-
dictive factors. The results of this study confirm the safety and the
short-term efficacy of the BIB®: at six months about the 70 per cent of the
treated patients lost at least 25 per cent of their excess weight. At
60 months follow-up 30 per cent of the patients were able to control their
weight loss and had at least 25 per cent of their EWL percentage. These
results indicate a possible role for BIB® in long-term weight loss control.
Intragastric Balloon in the Management of Morbid Obesity Disease
75

As far as the predictive factors are concerned, we have singled out three
different factors that bias long-term results; if they could be confirmed by
larger studies, BIB® use could be recommended in those younger than
35 years, women and those patients with an initial BMI between 35 and 40.27
The BIB® has been used only as a short-term treatment, but if prospective
studies involving a larger number of patients confirm these results, our
study suggests utilizing BIB® as a possible long-term treatment in selected
patients.
Effects of the weight loss on associated diseases; BIB® and
surgery; pre-operative strategy; sequential treatment
In our series the rapid weight-loss induced by the BIB® drastically affects
the progression of obesity-related diseases, thus determining the suspen-
sion or reduction of the pharmacological therapy (Table 5). The
dyslipidemic values improve in 58 per cent; there is significant hyperten-
sion control in 38 per cent. In 61 per cent joint diseases improved,
including pain regression and in 80 per cent the rapid weight loss led to
the prompt improvement of respiratory function and sleeping difficulties
with the disappearance of apnoea (breath-holding) attacks.28 As can be
observed in Fig. 6, after BIB® treatment the apnoea index ranged from 33
to 5 episodes/hour. Furthermore, weight loss induced by the intragastric
balloon, as demonstrated by various studies in the literature, led to a sig-
nificant reduction in intestinal fat and liver volume (Fig. 7): the role and
importance of the pre-surgery use of the intragastric balloon is clearly
76
A. Genco et al.
Table 5.
Weight loss effects on co-morbidities.
Cleared up (stopped
Improved (reduction
Unchanged
drug treatment) (%)
of drug treatment) (%)
(%)
Hypertension
38
52
10
Diabetes
36
45
19
Dislipidemia
58
28
14
Joint diseases
61
—
39
Respiratory function
80
—
20
Hyperinsulinemy
56.6
—
43.4

shown also in Busetto’s study,29 where the pre-LAP-BAND® treatment
together with BIB® induces a weight loss that shortens operating time and
reduces the intraoperative complications, the conversion rate for patients
subsequently subjected to gastric banding and hospital stay when compared
Intragastric Balloon in the Management of Morbid Obesity Disease
77
0
10
20
30
40
50
APNOEA
EPISODES /h
PRE BIB
POST BIB
Figure 6.
Apnoea episodes pre and post BIB® treatment.
Figure 7.
Intestinal fat and liver volume pre and post BIB.

with patients submitted directly to LAP-BAND® (Table 6). This is a fun-
damental condition for any patient candidate for surgery, in order to
reduce morbidity and intra- and post-operative complications. Moreover,
the weight loss induces an improvement in the size of the pharyngeal
cross-sectional areas related to the reduction of neck circumference, deter-
mining a reduction in the problems relating to orotracheal intubation,
often encountered with super-obese patients.1
In conclusion, the findings of the Italian LAP-BAND® and BIB®
(GILB group), in a study on 2,515 patients, indicate that the use of the
intragastric balloon induced an immediate normalization of the co-
morbidities in 44.3 per cent and a marked improvement in 44.8 per cent.
In only 10.9 per cent of the cases did the co-morbidities show no positive
effects whatever from the treatment.21
In addition, the Brazilian experience of 483 patients illustrates how
the BIB® affects obesity-related pathologies: clinical co-morbidities were
regarded as unchanged in 7 (9.2 per cent), improved in 31 (40.8 per cent),
and solved in 38 (50 per cent) patients.25
The use of the intragastric balloon is defined as ‘sequential treatment’
before any surgical treatment, whether bariatric or not, aimed at improving
co-morbidities in order to reduce surgical and anaesthesiologic complica-
tions deriving from such surgery.
When pre-operatively evaluating patients who are candidates for
bariatric surgery, careful attention must be paid to cardiologic, respiratory
diseases and functionality. Patients with morbid obesity frequently present
intubation and mechanical ventilation problems.1
78
A. Genco et al.
Table 6.
Busetto’s study data on operating time, hospital
staying, conversion rate and intra-operative complications.
BIB-LAPBAND
LAPBAND
(case pts)
(control pts)
Op time
82.5 ± 20.9
102.6 ± 35.1*
H stay
3.0 ± 0.2
3.3 ± 0.8*
Conversion
0/43 (0%)
7/43 (16.3%)*
IO Compl
0/43 (0%)
3/43 (7.0%)

In particular, pre-operative weight-loss achieved by means of an intra-
gastric balloon, which induces a significant improvement in obesity-
related pathologies, has been proposed, over the last few years, as an
effective way of reducing the intra, post and anaesthesiologic risks con-
nected with surgery on super-obese patients.30
The weight loss is associated with a reduction in the intestinal fat:
prospective studies have shown how, in relation to the weight loss (reduc-
tion of about 10 per cent of the initial weight) the volume of
abdominal–intestinal fat can vary (from 4.2 to 3.3, and even to 2.7), with
a weight loss of about 16 per cent.29
Similar modifications can also be seen with regard to hepatic volume.
It has been found that a weight reduction of about 10 per cent corresponds
to a reduction of 0.24 litres of hepatic volume, corresponding to a relative
decrease of 12.3 per cent.31 These modifications of the intra-abdominal
anatomy probably explain the positive impact on laparoscopic surgery of
the pre-operative weight loss achieved with the intragastric balloon. It is
evident that such changes are related to the weight loss and not to the use
of the BIB® per se. In any case, it has been demonstrated that the weight
loss obtained with the balloon is greater than the reduction achieved by
dieting alone.18,31,32
Another important role to be played by the intragastric balloon
derives from the results achieved by one of our studies which relates the
results obtained with BIB® to those achieved with the first step of the
bilio-pancreatic diversion.33 We must, however, bear in mind that laparo-
scopic biliopancreatic diversion with duodenal switch represents the
evolution of the operation described by Scopinaro34 and one of the most
successful surgical procedures for severe obesity.35,36 Long term studies
demonstrate that it is effective in super-obese patients with well known
results (EWL 75 per cent at ten-year follow-up).37 In 1999 Michel Gagner
described the first laparoscopic BPD and ‘duodenal switch’.38 In order to
decrease operative time and preoperative complications, the procedure
has been divided into two stages39:
•
a restrictive operation40 with tubulisation of the stomach and preser-
vation of the pylorus (sleeve gastrectomy);
•
a malabsorptive stage (BPD-DS)41,42
Intragastric Balloon in the Management of Morbid Obesity Disease
79

However, this technique demands two operations. For this reason the pur-
pose of this retrospective study was to verify the possibility of using BIB®
placement as an alternative approach in the preoperative setting for
patients who are candidates for major bariatric surgery.
The main result of the study is represented by the curve showing the
weight decrease in super-obese patients: the curves show no difference in
the slope between the two treatments: at six months follow-up there is no
statistically significant difference between the weight loss in the group of
patients treated with endoscopic placement of BIB® and the group of
patients operated on with a sleeve gastrectomy (Fig. 8). This result con-
firms that BIB® placement is an effective option in the bariatric
procedures. In fact when the BIB® is removed patients stop losing the
same amount of weight or even start gaining weight. At ten months
follow-up this trend is clearer and the difference between the two proce-
dures begins to appear significant. However, this fact confirms that in the
short period the endoscopic approach still maintains its value and appears
particularly useful when a temporary weight-loss is required. The study
also showed an influence on co-morbidities. In a recent study Gagner et al.
have shown similar results in terms of weight loss suggesting a possible
role for BIB® placement in a selected group of patients as a first stage of
BPD.43 In particular, BIB® placement appears highly advisable in those
patients who are candidates for BPD-DS, when operative and anaesthesi-
ologic risks due to co-morbidities are very high. The endoscopic approach
could reduce the entire treatment to a single stage surgical procedure
avoiding the operative complications of two operations.
Multiple treatment: What it is, why and when it is appropriate
This consists of placing two intragastric balloons one after the other,
respecting an interval of at least 30 days between the removal and the
second balloon placement.
The reason underlying the delay of at least one month is the need to
allow the patient to ‘get the feel’ of the balloon again. After about five
months’ treatment, in fact, the majority of patients feel a diminished sense
of satiety when compared with the first months of the treatment. This is
80
A. Genco et al.

probably due to the saturation of the gastric receptors which ‘adapt’ to the
presence of the intragastric prothesis. We observed that the placement of
the second BIB® (equal or higher volume compared to the first), after at
least one month’s delay, allows the patient to recover part of the sensitiv-
ity lost over the last few months of treatment with the first device. In any
case weight loss obtained with the second BIB® never exceeds 50 per cent
of the weight loss achieved with the first balloon.
The multiple treatment, as mentioned above, is to be taken into
consideration only under the following three conditions:
•
success of the first treatment (weight loss of at least 15 per cent of the
initial weight);
•
refusal of surgery;
•
as already observed, serious failure to alter eating behaviour (e.g.
sweet eating).
In our study 57 patients underwent multiple treatment. The mean weight
loss achieved with the second BIB® was 4.0 BMI and the overall weight
loss (with first and second BIB®) was 11.1 BMI (Table 7).
Intragastric Balloon in the Management of Morbid Obesity Disease
81
40
45
50
55
60
65
0
6
8
12
BMI
Months
BMI curve
SLEEVE
BIB
Figure 8.
Weight loss achieved with BIB vs Sleeve gastrectomy in super obese patients.