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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_1281_Библиотеки_им_академика_М_И_Перельмана
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Importance of Anesthesia in
2
Chapter 1
Pediatric La
paroscopic Procedures
AlejandroEscalona-Espinosa, RosinaAlcaraz-Ramos,
DavidAguilar-Romero and KeisukeLira-Hernandez
Abstract
Anesthesia plays a crucial role in pediatric laparoscopic procedures. It highlights
the unique challenges posed by laparoscopic surgery in young children and newborns,
and the need for specialized care in the selection and administration of anesthetics.
The text further investigates the physiological impacts of laparoscopic surgery, such
as hemodynamic changes due to increased intra-abdominal pressure, and potential
complications arising from prolonged CO2 absorption. The need for a pediatric anesthesiologist to be trained to perform good anesthetic techniques in these procedures,
such as increasing the ventilatory minute volume to counteract lethal effects, is also
analyzed.
Keywords: anesthesia, pediatric, laparoscopic surgery, intra-abdominal pressure,
pneumoperitoneum, CO2 absorption, hemodynamic alterations, ventilatory minute
volume
. Introduction
Laparoscopic surgery, which involves small incisions and advanced technology
for internal procedures, presents unique challenges in a pediatric setting. Anesthesia
is crucial for facilitating patient immobility, controlling pain, and ensuring a stable
state during the operation. Moreover, specialized care in the selection and administration of anesthetics in children is essential to minimize risk and ensure successful
recovery. This combination of precision in anesthesia delivery and laparoscopic
techniques allows for effective management of pediatric conditions, optimizing
clinical outcomes and the overall patient experience.
. Laparoscopic surgery
The laparoscopic technique in children and infants is still under development
and refinement. To date, there has not been extensive research on the effects of this
technique on systemic and cerebral oxygenation. Furthermore, the precise effects
of surgical maneuvers combined with conventional anesthesiologic procedures on
hemodynamic regulation remain controversial.
Pediatric Surgical Procedures – An Updated Guide – Volume I
3
Hemodynamic alterations associated with abdominal laparoscopy are attributed to
the increase in intra-abdominal pressure (IAP) generated by the creation of a pneumoperitoneum (PP) using CO2. The primary adaptive responses include decreased
venous return due to compression of the inferior vena cava, as well as increased
central venous and arterial pressures, with no apparent change in heart rate (HR) [1].
Laparoscopy involves the introduction of carbon dioxide into the surgical site to
facilitate visualization. CO2 remains the most used gas during laparoscopic surgery
due to its non-flammability, cost-effectiveness, and easy elimination from the respiratory system, although it has different biophysical properties under various thermal
conditions. In long-term laparoscopic surgery, prolonged absorption and accumulation of CO2 can lead to hypercapnia, which can cause hypertension, tachycardia,
and other complications [2]. These changes lead to pressure-related acidosis. To
counteract the respiratory alterations after insufflation, it is necessary to increase the
ventilatory minute volume by a pediatric anesthesiologist. Research has shown that
this increase in CO
is inversely correlated with age, possibly because the peritoneum
2
of infants is proportionally larger and better perfused [3].
The pneumoperitoneum also generates cardiovascular effects by increasing intraabdominal pressure, CO2 absorption through the peritoneum, and stimulation of the
neurohumoral vasoactive system. In young children, aged 6–36months, an intraabdominal pressure of 10mmHg or more (higher than right atrial pressure) leads to
a decrease in venous return, right ventricular cardiac output, as well as preload, and
left ventricular cardiac output. In addition, increased intra-abdominal pressure may
trigger the release of catecholamines, contributing to an increase in mean arterial
pressure and systemic vascular resistance. In pediatric patients, bradycardia may also
develop due to a strong vagal reflex induced by the pneumoperitoneum, which may
require emergency disinflation [4].
Li-Wei conducted a study to observe hemodynamic and respiratory changes in
36 neonates undergoing laparoscopic surgery. They administered intra-abdominal
pressure with pneumoperitoneum between 8 and 14mmHg and cannulated an
arterial line to measure heart rate (HR), oxygen saturation (SPo2), mean arterial pressure (MAP), partial pressure of carbon dioxide (PaCO2), and arterial
pH. Li-Wei found significant differences in HR (p=0.05), an increase in PaCO2
(p=0.05), and a decrease in pH at 20minutes with a significant p-value of 0.05,
concluding that the pressure of pneumoperitoneum with CO2 in neonates should
be maintained in a narrow range of 8–14mmHg to avoid hemodynamic and
respiratory changes [5].
Pathophysiological hemodynamic alterations during laparoscopic procedures in
children have not yet been fully explored. Therefore, in young children and in longterm surgeries, standardization of minimally invasive intraoperative assessment
requires rigorous anesthetic monitoring to prevent possible adverse hemodynamic
outcomes [6, 7]. In most studies, a 10–30% reduction in cardiac output has been
observed with significant pathophysiological changes, highlighting the importance of
specialized anesthetic support in pediatric laparoscopy, especially in infants.
In a small sample of eight young infants, hemodynamic measurements were
performed through transesophageal echocardiography, assessing the CO
insufflation
2
pressure at a CO2 pressure of 12mmHg. An increase in blood pressure and systemic
vascular resistance, a decrease in HR and cardiac index (CI), systolic wall stress,
end-diastolic and end-systolic index, and a decrease in shortening fraction (AF)
with a p-value of 0.05 were observed. Regarding the movement of the wall of the left
ventricle, it caused a reduction in the septal wall and hyperkinesia of the lateral wall
Importance of Anesthesia in Pediatric Laparoscopic Procedures
DOI: http://dx.doi.org/10.5772/intechopen.115024
4
without the latter being statistically significant. All these changes decreased with
insufflation pressures of 6mmHg [8].
Hypothermia and hypercapnia are two major concerns in laparoscopic surgery, as
systemic hypothermia and hypercapnia can cause arrhythmias and acidosis, respectively. These conditions can have profound consequences, such as brain injury or even
death. Fortunately, well-known strategies have been developed to prevent these complications in this pediatric surgical setting. These strategies include the use of external
warming blankets, intravenous fluid warming, CO2 gas humidification, reduction of
gas leaks to minimize persistent cold gas ingress, and adjustment of ventilator minute
volume and peak inspiratory pressure. In addition, disproportionately increasing the
respiratory rate during CO2 insufflation is considered necessary, such as setting the
respiratory rate at 50–60/min in patients with a body weight of less than 4kg [9].
Fujimoto T et al. evaluated minute volume in 65 neonates with an intra-abdominal
pressure of 8mmHg, observing that all neonates presented hypercapnia with CO2
levels between 48 and 61mmHg with a fixed minute volume of 200ml/kg/min,
which had to be adjusted by 30–40% more to achieve adequate CO2 levels. Therefore,
the recommended pressures for younger infants are 8–12mmHg and beginning insufflation with the lowest possible CO2 flow is identify any adverse physiological changes
and their immediate reversal [10].
Continuous monitoring is essential during anesthesia in neonates and premature
infants. This includes monitoring of heart rate, blood pressure, oxygen saturation,
capnography, and body temperature. Invasive monitoring, such as invasive blood
pressure or central venous pressure monitoring, may be necessary in selected cases
for a more accurate assessment of hemodynamic status. Postoperative pain management is also important in neonates and premature infants. Multimodal techniques
including opioid analgesics, local anesthetic agents, and regional techniques such as
peripheral nerve blocks can be used to minimize the need for systemic opioids and
reduce side effects.
. Preoperative evaluation
Every patient must undergo a medical and anesthetic evaluation, including a
directed physical examination and relevant medical history, to evaluate comorbidities
that may impact the toleration of the surgery as well as the response of the physiologic
changes due to laparoscopic surgery. Congenital malformation may be present, thus
it is important to individualize each patient and consult the required specialist (e.g.,
pediatric cardiologist) if needed to be prepared and lower the intraoperative risks
during surgery. This management requires an experienced anesthesiologist [2].
Preoperative assessment for laparoscopic procedures in the pediatric population
is an essential process to ensure the safety and success of the surgical intervention.
This comprehensive examination encompasses several clinical and medical aspects to
tailor care to the specific needs of each pediatric patient. Based on the above, we will
describe some key considerations in the preoperative evaluation for these procedures
in the pediatric population; however, it is important to take into consideration the
cognitive role of the patient to obtain a complete and more accurate assessment [11]:
• Detailed Medical History: Comprehensive review of the patient’s medical history,
including family history, previous medical conditions, allergies, and current
medications.
Pediatric Surgical Procedures – An Updated Guide – Volume I
5
• Physical Examination: Complete assessment of the patient’s general condition,
focusing on cardiorespiratory function, physical development, and the presence
of any abdominal abnormalities.
• Imaging studies: Imaging studies, such as ultrasound or CT scans, are performed
to obtain a detailed visualization of the abdominal anatomy and to assess the
need for and feasibility of laparoscopy.
• Laboratory: Analysis of laboratory tests to assess renal, hepatic, and hematologi-
cal function, as well as blood coagulation.
• Psychological preparation: Consideration of the emotional and psychological
preparation of the pediatric patient and their parents for surgery.
• Multidisciplinary coordination: Collaboration with other pediatric specialists as
needed, such as cardiologists, anesthesiologists, and intensive care specialists.
• Anesthetic planning: Thorough assessment of the patient by the anesthesiology
team to determine the most appropriate anesthetic strategy.
• Informed Consent: Obtaining informed consent from parents or legal guardians,
explaining in detail the risks and benefits of laparoscopy.
• Specific Considerations: Assessment of specific considerations for laparoscopy,
such as patient positioning, intra-abdominal pressure, and continuous monitoring.
• Postoperative planning: Establishment of a postoperative plan, including pain
management, postoperative observation, and discharge instructions.
Preoperative assessment from an anesthesiologist’s point of view is a comprehensive process that requires an individualized approach for each patient, thus ensuring
safety and well-being during and after the surgical procedure (Figure ) [11].
Figure 1.
Process of preoperative anesthetic evaluation in pediatric patients.
Importance of Anesthesia in Pediatric Laparoscopic Procedures
DOI: http://dx.doi.org/10.5772/intechopen.115024
6
. The importance of pediatric anesthesiologists during laparoscopic
procedures
Maintenance of anesthesia during laparoscopic surgery in pediatric patients is a
critical process that seeks to ensure hemodynamic stability, adequate muscle relaxation, and patient comfort. Anesthesia during laparoscopy in neonates and premature
infants is a delicate and crucial issue in medical practice, as these patients are especially vulnerable due to their physiological and anatomical immaturity. Neonates and
preterm infants have unique anatomical and physiological characteristics that must
be considered during anesthesia. Their airway is narrower, and their cardiovascular
system is still developing, which may affect the response to surgical stress and the
ability to maintain homeostasis during the procedure.
Anesthetic induction is key for these procedures, as anxiety and fear of the procedures is quite common in the pediatric population. This is why induction must be
accompanied by age-appropriate preoperative management to maintain the desired
comfort. A gentle and gradual anesthetic induction is performed, preferably with
inhalation or intravenous agents adapted to the age and weight of the patient. The
main goal of anesthesia is to facilitate surgery with the least possible risk to the patient
and to ensure a gentle induction and optimal recovery after the surgical procedure.
The choice of volatile agent plays a key role in the induction and recovery from
anesthesia. Those agents with lower solubility in blood gases have been shown to have
faster times in these processes. An ideal inhaled anesthetic agent should be characterized by low solubility in blood gases, minimal pungency, negligible respiratory irritation, resistance to metabolic and physical degradation, and ready availability [12].
The most used volatile inhalation anesthetics include nitrous oxide, desflurane,
isoflurane, halothane, enflurane, among others. Halothane is frequently used as an
anesthetic agent in pediatrics due to its non- irritant nature and its ability to induce
anesthesia gently and rapidly in children [13].
In the management of the airway during surgery, pediatric anesthesiologists are
the most qualified in this area because the pediatric difficult airway is one of the most
challenging clinical situations faced by physicians. This is due to their short tolerance
to apnea, propensity to airway oedema, and anatomical changes during growth [14].
A patent airway and adequate oxygenation are ensured. Smaller endotracheal tubes
and supraglottic devices may be considered depending on age.
Non-anesthesiologists are often responsible for airway management in pediatrics or neonatal patients, leading to a significantly increased risk of adverse events
during airway management. These adverse events are often associated with tracheal
intubation (TIA). Although the definition of adverse events associated with tracheal
intubation does not encompass hypoxemia, they are often reported together [15].
Current evidence indicates that (1) both tracheal intubation-associated adverse events
and hypoxemia are common incidents in airway management in pediatric intensive
care units, emergency departments, as well as neonatal intensive care units, including
laparoscopic surgeries; (2) various factors, such as patient characteristics, physician
skills, and clinical practices, are linked to the occurrence of these adverse events;
and (3) interdisciplinary quality improvements have contributed to a decrease in the
frequency of these events. In this context, collaboration between pediatric anesthesiologists and non-anesthesiologists may be an effective strategy to improve airway
safety in these clinical settings [16].
During laparoscopic procedures, general anesthesia is ideally used, for which
mechanical ventilation is performed with controlled pressures and volumes adjusted
Pediatric Surgical Procedures – An Updated Guide – Volume I
7
to maintain adequate oxygenation and carbon dioxide removal. Ensuring optimal
ventilation during invasive ventilation contributes to lung protection. High ventilation pressures, high tidal volumes, and the formation of regional atelectasis contribute significantly to ventilator-induced lung injury. Respiratory physiology in children
has specific characteristics that make the diaphragm particularly prone to dysfunction. Due to the greater flexibility of the abdomen and a smaller contact area between
the diaphragm and rib cage in infants, contraction of the diaphragm does not result
in the same expansion of the lower ribs as in adults. In addition, the high flexibility of
the chest wall and the horizontal arrangement of the ribs may cause distortion during
inspiration, especially during sleep with rapid eye movements or in situations of
respiratory distress [17].
The combination of these characteristics, together with smaller distal airways,
results in high parietal compliance in neonates and infants. This condition implies
that the end-expiratory lung volume must be maintained above the relaxation
volume of the respiratory system, known as dynamic hyperinflation. This phenomenon is achieved by delayed expiratory airflow resulting from contraction of the
laryngeal muscles (in infants without an artificial airway) or persistent activation
of the diaphragm during expiration. Thus, the diaphragm may be active during both
inspiration and expiration. In contrast, during conventional pediatrics mechanical
ventilation, the diaphragm tends to remain inactive [18].
Most patients require mechanical ventilation (MV) during surgical procedures,
and improving intraoperative MV management may decrease the frequency of
postoperative pulmonary complications and improve treatment outcomes. Lung
ventilators are becoming increasingly sophisticated and require technical skills, and
it is necessary to adjust the ventilation mode to achieve low tidal volume (VT) and
low positive end-expiratory pressure (PEEP). It is crucial to calculate VT based on
ideal rather than actual body weight. Currently, there is no unmistakable evidence to
support the benefits of any specific mode of ventilation [19].
With MV, alterations in intrapleural and intrathoracic pressure and lung volume
occur, and these variations impact the cardiovascular system. Changes in atrial
filling (preload), ventricular emptying resistance (afterload), heart rate, and myocardial contractility are observed. Changes in intrathoracic pressure affect intrathoracic structures such as the heart, pericardium, and large arteries and veins.
As volume increases, the lungs exert an increasing force on the heart, chest wall,
and diaphragm. Simultaneously, the chest wall expands outward, the diaphragm
descends, and the heart, pericardium, and coronary arteries are compressed by the
lungs [20].
The impact of mechanical ventilation during laparoscopy on the heart and hemodynamics is conditioned by the choice of ventilation mode and alterations in intrathoracic pressure and lung volume. Different ventilatory regimens may generate a similar
effect on hemodynamics when intrathoracic pressure and lung volume are identical.
Cardiac output (CO) remains constant at equal tidal volume (VT) and increases with
decreasing volume. Research indicates that CO decreases when the lungs experience
inflammation [21]. This is why the pediatric anesthesiologists continuously monitor
blood pressure, heart rate, and oxygen saturation to detect any changes in hemodynamic stability.
Specifically, laparoscopy is associated with more favorable cosmetic results,
shorter hospitalization periods, less postoperative pain, and faster recovery to resume
daily activities. However, it is not without potential short- and long-term complications, which may include mild pain, abdominal discomfort, and adhesion formation.
Importance of Anesthesia in Pediatric Laparoscopic Procedures
DOI: http://dx.doi.org/10.5772/intechopen.115024
8
During the insufflation of carbon dioxide to create the pneumoperitoneum, intraabdominal pressure is carefully controlled to minimize adverse effects on cardiovascular and pulmonary function. The pneumoperitoneum is essential in laparoscopic
surgery, as it allows visibility and mobility in the workplace. However, pneumoperitoneum modifies the homeostasis of the abdominal cavity and may promote metabolic
changes through mechanical and biochemical effects [22].
It has been shown that the chemical, physical, and biological properties of
pneumoperitoneum can affect clinical outcomes, such as postoperative pain, length
of hospital stay, and recovery time. These data indicate that the chemical, physical,
and biological effects of CO2 on the peritoneum can trigger inflammatory processes
and tissue alterations. In particular, the magnitude of morphological changes has
been found to correlate with intra-abdominal pressure levels. The initiation of CO
2
pneumoperitoneum induces an inflammatory response that modifies factors such as
chemokine levels in both plasma and peritoneum [23].
In the era of minimally invasive surgery, it is essential to understand the essential
physiological mechanisms that undergo changes during laparoscopy and pneumoperitoneum to make this surgical approach even less invasive. The peritoneum,
which lines the abdominal cavity, is positioned as the main actor in generating these
laparoscopy-induced changes. This lining maintains an exceptional balance between
various components and factors, including chemokines, which play a crucial role
in the activation and recruitment of leukocytes to inflammatory sites. Laparoscopy
impacts both the integrity and biology of the peritoneum, alters the immune system,
and leads to peritoneal acidosis through CO2 insufflation and its influence on microcirculation. Although it is not fully elucidated how these factors interact with each
other and how they translate clinically, understanding these mechanisms represents
the challenge in achieving truly minimally invasive surgery [24].
To help minimize complications, maintenance anesthetic depth is important,
adjusting the depth of anesthesia as needed, using inhalation agents or intravenous
drugs to ensure balanced anesthesia. Anesthesia is maintained by a volatile agent in
combination with oxygen and air. Both isoflurane and halothane have been shown
to be effective in this context. However, an increased risk of arrhythmias has been
observed when halothane is used in spontaneously breathing patients due to hypercapnia. In addition, a potential risk of hepatotoxicity associated with halothane,
related to decreased hepatic blood flow, has been identified. Isoflurane, on the other
hand, has been shown to be associated with excessive secretion production and bronchospasm. Total intravenous anesthesia (TIVA) using a propofol infusion has been
successfully implemented, although a 20% or greater increase in minute ventilation
is required to maintain normocapnia. Nitrous oxide is avoided as it may contribute to
intestinal distension, nausea, and vomiting.
Despite care, there are risks and complications associated with anesthesia in
neonates and premature infants, such as respiratory depression, hypotension, bradycardia, pulmonary aspiration, airway injury, and anesthetic neurotoxicity. It is
important to assess and mitigate these risks in each individual case. Safe management
of anesthesia in neonates and premature infants requires a well-coordinated multidisciplinary team that includes pediatrics anesthesiologists, pediatrics surgeons, neonatologists, specialized nurses, and other health care professionals. In addition, staff
must receive specialized training in the anesthetic care of this vulnerable population.
Effective maintenance of anesthesia during pediatric laparoscopic surgery requires
careful and personalized care, considering the unique characteristics of each patient
and the specific demands of the surgical procedure (
Figure ).
Pediatric Surgical Procedures – An Updated Guide – Volume I
9
Figure 2.
Types of anesthesia, laparoscopic procedures and medications used.
. The role of the anesthesiologists in the postoperative period
Postoperative monitoring plays a crucial role in the follow-up and care of the
patient after surgery, covering several key aspects. Vital signs, including heart rate,
respiratory rate, temperature, and blood pressure, are constantly assessed, providing
vital information on the patient’s physiological status and allowing for the detection
of complications or responses to the recovery process. In addition, oxygen saturation
is continuously measured by pulse oximetry to ensure adequate oxygenation, particularly relevant in patients undergoing surgery, as it helps to quickly detect any drop in
oxygen levels that could indicate respiratory or circulatory problems.
Simultaneously, the assessment of the state of consciousness is conducted, which
is essential to detect possible neurological complications or changes in the patient’s
response to anesthesia. Aspects such as response to stimuli, orientation in time and
space, and the ability to communicate coherently are observed. Although pain perception is subjective, any postoperative discomfort or pain is assessed and addressed.
Observation of respiratory rate, respiratory pattern, and the presence of any
respiratory distress are important aspects of postoperative monitoring, especially in
procedures that may affect pulmonary function, such as abdominal surgery. At the
same time, intravenous fluid infusion is administered and monitored, essential to
maintain an adequate water and electrolyte balance during the recovery phase. This
constant monitoring allows early detection of immediate postoperative complications, such as excessive bleeding, allergic reactions to medications, or anesthesiarelated problems.
Meticulous attention to these aspects of postoperative monitoring contributes significantly to the early identification of potential problems and effective management
of patient recovery, and this comprehensive approach is essential to ensure a safe and
successful recovery process.
Effective communication with the patient, especially in the case of children,
is crucial to determine pain intensity and adjust analgesic medication as needed.
Effective pain management is a critical aspect of the postoperative process, and the
presence of a pediatric anesthesiologists plays a key role in this aspect, especially in
Importance of Anesthesia in Pediatric Laparoscopic Procedures
DOI: http://dx.doi.org/10.5772/intechopen.115024
10
the context of laparoscopic procedures in children. The adaptation of appropriate
analgesic strategies is essential to ensure the well-being of the pediatric patient. The
pediatric anesthesiologists not only evaluates and selects pain medications carefully
but also considers non-pharmacological techniques that can contribute significantly
to pain management.
In the case of pediatric laparoscopy, the choice and administration of analgesics
should be tailored to the age and individual needs of each patient. Pediatric anesthesiologists consider the specific physiological and pharmacokinetic characteristics of
children, tailoring doses, and types of drugs to achieve optimal analgesia. In addition,
effective communication with the patient and caregivers is essential to understand
pain perception and adjust the analgesic plan as needed.
The pediatric anesthesiologists may also implement non-pharmacological techniques, such as distraction or cognitive behavioral therapy, especially in older children, to complement pharmacological pain management. Lidocaine patching, the use
of patient-controlled analgesic infusions (PCA), and consideration of regional nerve
blocks are additional strategies that pediatric anesthesiologists can employ to optimize analgesia in the postoperative period. Thus, a pediatric anesthesiologist plays an
integral role in the management of pain after laparoscopy in the pediatric population,
ensuring personalized and effective care that contributes to a more comfortable and
satisfactory recovery for the patient.
. Conclusion
Anesthesia in pediatrics laparoscopic procedures plays an essential role in ensuring
the safety, well-being, and success of the surgical intervention. The combination of
laparoscopic surgery, with its advantages in terms of clinical outcomes and recovery,
together with the careful and specialized administration of anesthesia, allows a
variety of pediatrics conditions to be effectively addressed.
From the preoperative evaluation, where a thorough review of the medical history,
detailed physical examination, and multidisciplinary studies and interventions are
coordinated, to the anesthetic planning tailored to the specific needs of each patient,
the presence of pediatric anesthesiologists is imperative. Consideration of factors
unique to the pediatric population, such as apnea tolerance and airway anatomy,
highlights the need for specialized expertise in this field. During the actual laparoscopic procedure, specific hemodynamics and respiratory challenges are addressed,
such as alterations associated with pneumoperitoneum and adaptation to CO2
properties. Constant monitoring of hemodynamics stability and ventilation, as well
as the ability to adjust anesthesia as needed, demonstrate the skill of the pediatrics
anesthesiologists.
The selection of anesthetic agents should be careful. Agents with rapid onset and
recovery, as well as minimal elimination by the patient, are preferred to minimize
the risk of adverse effects. In general, the use of total intravenous general anesthesia
is preferred over inhalation anesthesia because of its lesser impact on the respiratory
system. It is crucial to maintain a patent airway and adequate ventilation throughout
the procedure. In neonates and premature infants, smaller and more delicate airway devices may be required, as well as careful adjustments in ventilation to avoid
hypoventilation or hyperventilation, which can have profound consequences.
In the postoperative period, continuous monitoring of vital signs, assessment of
consciousness, and effective pain management are essential for a successful recovery.
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