The American Society of Anesthesiologists (ASA) defines general anesthesia in the following way: “General anesthesia is medicine that is administered by an anesthesiologist, a medical doctor, through a mask or an IV placed in the vein.” While it is working, a patient will be unconscious, and many of the body’s functions will slow down or need help to work effectively. Most pediatric patients who need pain control for procedures undergo general anesthesia so that they are rendered unconscious, as most children cannot tolerate holding still for even the simplest procedures. An important aspect of the success of pediatric general anesthesia is the preoperative work that happens before the child goes to sleep. Often, children fear the hospital setting and are particularly afraid of needles. In addition to these fears, children suffer from separation anxiety from their parents or guardians. To help combat these fears and to ease the transition from the caregivers to the healthcare team, an anxiolytic medication is often administered prior to the procedure. Most commonly, this is oral midazolam, a benzodiazepine. Many studies have shown the effectiveness of preoperative anxiolysis, which includes memory loss related to the anxiety experienced prior to surgery.

According to the ASA, “Regional anesthesia is a type of pain management for surgery that numbs a large part of the body, such as from the waist down.” Regional anesthesia includes both peripheral nerve blockade and neuraxial techniques such as epidurals and spinal blocks. There is a growing list of indications for regional anesthesia, and many pediatric centers have a dedicated pain service that helps perform and manage these blocks. One of the key aspects of a successful pain program is communication with the surgeons and surgical teams. Regional anesthesia can be used for a variety of situations, including trauma, elective surgery, and chronic conditions.

One of the many advances in anesthetic technique comes in the form of sedation, which helps to relax a patient for a simple procedure. Sedation avoids the potential complications of general anesthesia and helps to reduce the risk and side effects that are encountered with anesthetic medications. The ASA defines sedation as the following: “Sedation, also known as monitored anesthesia care, conscious sedation, or twilight sedation, typically is used for minor surgeries or for shorter, less complex procedures, when an injection of local anesthetic isn’t sufficient but deeper general anesthesia isn’t necessary.” Some examples of procedures for which sedation is used include superficial biopsies, liver biopsies, hormone implant device placement, and minor dental procedures.

Sedation is provided on a spectrum from minimal to deep sedation. The levels of sedation are delineated by the patient’s control of respiration and response to verbal, tactile, and painful stimuli. With minimal sedation, a patient is relaxed but awake and can answer questions. With moderate sedation, a patient is more drowsy than minimal sedation and may or may not recall the procedure. Deep sedation allows a patient to sleep through a procedure with little recall. In most pediatric institutions, deep sedation is required because children often are unable to tolerate even minor procedures. It is important that patients are frequently monitored during sedation, especially during deep sedation. It is recommended that the person performing the procedure is not simultaneously administering the sedation. It is easy for a patient undergoing deep sedation to slip into unconsciousness and general anesthesia. In this state, the patient may no longer be able to protect their airway and is more likely to have complications. Like all anesthetic techniques, having a well-developed preprocedure plan and clear lines of communication are critical to the safety of our patients.

The most common inhaled anesthetics in pediatric practice include nitrous oxide and the halogenated ethers sevoflurane, desflurane, and isoflurane. They produce unconsciousness, amnesia, and immobility in a dose-dependent fashion. They have variable onset, potency, clinical indications, physiologic consequences, and side effects. The mechanism of action is not completely understood, but modulation of ion channels in the central nervous system is thought to be responsible for the clinical effects. At the neural network level, volatile anesthetics block functional connectivity between brain regions and produce immobility via suppression of reflex pathways at the spinal cord level.

The potency of inhaled anesthetics is measured with a unit called minimum alveolar concentration (MAC), in which one MAC is defined as the concentration of an inhaled anesthetic required to produce immobility in 50% of patients as a response to a noxious stimulus. Combining more than one anesthetic such as 0.5 MAC nitrous oxide and 0.5 MAC sevoflurane will create a clinical effect of 1.0 MAC. MAC levels for individual patients may be higher or lower based on many factors including age, substance use, electrolyte abnormalities, and acute illness. Combining other agents that modulate pain or sedation into the anesthetic plan also will decrease the amount of inhaled anesthetic necessary to provide unconsciousness or immobility.

Nitrous oxide is an odorless gas with a MAC value of 104% (a concentration of 104% nitrous oxide at sea level will prevent movement in 50% of patients), and it is the least potent of the anesthetic gases. Delivery is limited to less than 75% due to the need to avoid delivering a hypoxic mixture to the patient. For this reason, it is considered a weak anesthetic. It is commonly used in pediatric anesthesia as part of a balanced anesthetic technique. Due to its lack of odor, nitrous oxide can be tolerated by children as an anxiolytic during peripheral IV placement before being combined with sevoflurane to speed the uptake of the more potent agent. Due to its higher solubility in blood and tissues compared to nitrogen, it can rapidly accumulate in closed spaces much faster than nitrogen can diffuse out. Therefore, nitrous oxide should be avoided in patients with small bowel obstruction, pneumothorax, and middle ear surgery.

The halogenated ethers include sevoflurane, desflurane, and isoflurane. These agents are liquid at room temperature and are delivered through a vaporizer system. Sevoflurane is the most used inhaled anesthetic in children, due to its ability to be used as an induction agent. Isoflurane and desflurane are more pungent and irritating to the airways and are not suitable for induction. Isoflurane and desflurane are mainly used for maintenance of anesthesia. All of the inhaled anesthetics are ozone-depleting greenhouse gases, and their environmental impact has been increasingly scrutinized. Efforts to limit the damaging effects include using lower fresh gas flows, lower inspired concentrations of anesthetic gases, and use of alternative anesthetic agents.

Intravenous (IV) anesthetics are essential in providing sedation and anesthesia in ORs, emergency departments, procedure suites, and ICUs. This category contains a wide variety of medications in terms of mechanism of action, typical use, and physiologic side effects.

Propofol is the most frequently used IV anesthetic in modern anesthesia practice. As an induction agent, it causes rapid hypnosis and suppression of airway reflexes necessary for intubation. It can also be used as a sole anesthetic for maintenance of anesthesia, called total intravenous anesthesia (TIVA). Although it is a respiratory depressant, general anesthesia can be maintained while retaining spontaneous ventilation for procedures such as endoscopy and airway procedures through carefully titrated infusion. Propofol decreases the cerebral metabolic rate for oxygen as well as cerebral blood flow, which can be useful in reducing intracranial pressure compared to inhaled anesthetics. Propofol is a preferred maintenance agent for spine surgeries, where neuromonitoring with evoked potentials is not impaired. Propofol has antiemetic properties, which makes an infusion ideal for patients with a history of postoperative nausea and vomiting.

Barbiturates include thiopental, methohexital, and pentobarbital. Their use has decreased significantly since the development and widespread adoption of propofol. Methohexital is common in adult anesthesia practice for providing optimal conditions for electroconvulsive therapy. Thiopental and pentobarbital are rarely used for procedural sedation or induction of anesthesia but are used in critically ill patients to treat elevated intracranial pressure and refractory status epilepticus.

Benzodiazepines include diazepam, lorazepam, and midazolam. Diazepam and lorazepam are infrequently used by pediatric anesthesiologists in the OR, but patients with postsurgical muscle spasms, critically ill patients requiring sedation, and patients with epilepsy may be prescribed these medications. Midazolam is the most common benzodiazepine used by pediatric anesthesiologists. It is useful as a preoperative anxiolytic and can be administered orally, intravenously, or intranasally. It has anterograde amnestic properties, which may aid in decreasing traumatic memories in young patients. It also is commonly used in ICUs as a sedative for ventilated patients.

Ketamine is a phencyclidine derivative with analgesic and anesthetic properties. While the IV anesthetics described above have a mechanism of action via GABAergic receptor potentiation, ketamine is unique in its antagonism of NMDA receptors. It is commonly used as for induction of anesthesia, procedural sedation, and an adjunct analgesic for treatment of chronic and acute postoperative pain. Common side effects include nausea, excessive salivation, and hallucinations. It is commonly coadministered with a benzodiazepine to decrease negative psychological experiences.

Etomidate is rarely used in pediatric anesthesia. Historically, it is noteworthy for inducing general anesthesia without causing significant hemodynamic changes such as hypotension or tachycardia. Etomidate has been shown to inhibit endogenous corticosteroid production, which has limited its widespread use.

Dexmedetomidine is a selective, short-acting alpha-2 adrenergic receptor agonist that is commonly used in pediatric anesthesia and critical care. Its sympatholytic effects include pain modulation and sedation with less respiratory suppression compared to other medications. It can be used as an anxiolytic, perioperative adjunct for MAC-sparing and opioid-sparing effects and for prevention of emergence delirium. It is also commonly used in the ICU for sedation of critically ill patients.

Postoperative nausea and vomiting (PONV) is a significant patient and family dissatisfier that can prolong hospital stays. Risk factors that may increase the incidence of PONV in the pediatric population include age greater than three, eye surgery, prolonged surgery, and history of PONV (self and/or family). ^, Numerous pharmacologic agents are utilized to decrease the incidence of PONV, and the combination of dexamethasone and ondansetron are commonly used in patients aged two and older. A propofol infusion for maintenance of anesthesia may also be utilized instead of inhaled anesthetics to help decrease the risk of PONV. Many enhanced recovery after surgery (ERAS) pathways also incorporate antiemetics such as aprepitant (an NK1 receptor antagonist that blocks substance P) and scopolamine in the preoperative period. Table 3.2 summarizes commonly used antiemetics in the pediatric population undergoing surgery. ^,

Most pediatric surgeries are performed on an outpatient basis in either a hospital or ambulatory surgery center (ASC). ASCs are often more cost effective, and thus it stands to reason that the number of pediatric surgeries performed at ASCs will continue to increase. Most pediatric institutions have defined criteria for ambulatory surgery, but in general patients are expected to be healthy and capable of being discharged home. Ambulatory surgery would not be appropriate for patients who have significant medical comorbidities or those with a high likelihood of prolonged postoperative monitoring and care needs.

Many pediatric centers have a preadmission testing (PAT) or preanesthesia testing clinic. This testing allows patients to be seen and evaluated prior to surgery. The goal is to optimize the patient before the planned surgical procedure, which helps reduce the risk of harm and perhaps reduce the risk of an unscheduled postoperative admission or cancellation on the day of surgery. The criteria for PAT vary, but some conditions that require PAT include family history of malignant hyperthermia or major anesthetic complications, uncontrolled asthma or other significant airway/lung disease, a new murmur or significant history of cardiac disease, endocrinopathy, end-stage renal disease, liver disease, hematologic disorders, prematurity and low postconceptual age, significant neurologic problems, and children with syndromes or major genetic disorders (e.g., trisomy 21, Pierre Robin sequence). Patients with chronic pain conditions or with scheduled surgeries that may require extensive postoperative pain management may also benefit from a PAT visit.

A thorough past medical history is particularly important before administering any anesthetic. This history should include a complete review of systems (ROS) to uncover and understand any issues that might change the type of anesthetic that is prescribed. The information gathered in the ROS could also uncover issues (e.g., cardiac, endocrine, airway) that must be explored with other consultants prior to administering anesthesia.

In addition to the ROS, all patients need to have any allergies documented. This documentation should include the reaction to the offending agent. The categories of allergies that should be reviewed are medications, food, tape, and latex. Anaphylactic reactions are uncommon but can be lethal. Should anaphylaxis manifest, immediate resuscitation should be started and a tryptase level drawn within 4 hours of the reaction because this level will determine whether anaphylaxis has occurred. The patient will then need to undergo further allergy testing to determine what agent caused the reaction.

Importantly, outlining a patient’s prior past anesthetic history will help determine if there were any issues or complications with prior anesthetics. For example, it is helpful to know if a patient experienced nausea and vomiting in the past so that a potential different anesthetic can be prescribed. The prior history can also reveal whether a difficult airway was encountered and what measures were taken to secure the airway.

It is also important to inquire about a patient’s family history, especially as it relates to anesthesia. Specifically, all patients should be asked about malignant hyperthermia, a rare but life-threatening condition encountered with certain triggering anesthetic agents. Additionally, practitioners should ask about any history of prolonged muscle paralysis after the use of succinylcholine, which could indicate the presence of a pseudocholinesterase deficiency. Patients with this condition can experience muscle paralysis for many hours after receiving succinylcholine, which requires endotracheal intubation and subsequent placement on a ventilator until the paralysis resolves.

A general physical examination should be completed and documented prior to administering anesthesia. This examination should include a basic neurologic examination that notes the patient’s level of consciousness, muscle tone, and general appearance. An examination of the cardiovascular system should include auscultation of the heart, listening specifically for murmurs and an irregular heartbeat. Innocent murmurs are frequently encountered, but a new murmur should prompt further workup and evaluation. The respiratory system should also be examined, which includes listening to the chest for breath sounds and listening specifically for wheezing, rhonchi, and rales. Issues such as coughing, sneezing, and a runny nose can also be observed during the physical examination. The presence of any of these neurological, cardiovascular, or respiratory issues can impact the anesthetic course, and caution is warranted before proceeding with the surgery. For emergent cases that must proceed, these issues should be documented, and the risks should be explained to the patient and family.

Routine laboratory testing is not needed for most pediatric anesthesia procedures. For procedures in which significant blood loss is anticipated, a preoperative hemoglobin level is appropriate. Preoperative laboratory testing might be indicated for other conditions, such as diabetes, and for patients taking certain medications such as seizure medications or diuretics. The routine use of preoperative urinalysis is also not indicated unless a condition such as a urinary tract infection is suspected. Pregnancy testing is controversial, and many institutions have their own policies on this topic. At our institution, all female patients 10 years of age or older are tested for pregnancy. Ultimately, the condition and health status of the patient will help determine if routine preoperative laboratory testing is needed.

The practices of anesthesia and surgery have become much safer over the last several decades. Progress has been made through advances in medications, equipment, monitoring, subspecialty training, research, and a collaborative effort to enhance patient safety. The field of anesthesiology has several organizations and teams with a stated goal of improving patient outcomes. In 1984, The American Society of Anesthesiologists (ASA) Closed Claims Project began collecting malpractice claims data, identifying the etiology of major patient injuries resulting in compensation, and designing preventative strategies to reduce future harm. In 1994, the ASA formed the Pediatric Perioperative Cardiac Arrest (POCA) registry, which collects and analyzes circumstances of pediatric cardiac arrest. The Society for Pediatric Anesthesia sponsors Wake Up Safe, which maintains a registry of pediatric outcomes data via submission of detailed event information from member institutions. The Food and Drug Administration and International Anesthesia Research Society have formed a partnership called SmartTots, which aims to close the clinical and scientific gaps in the safe use of anesthetics and sedatives in children.

The landmark publication “ To Err is Human: Building a Safer Health System ” published by the Institute of Medicine in 2000 highlighted that the field of anesthesia has shown some of the most impressive improvements in patient safety through the development of systematic approaches to error reduction and systems engineering. It estimated that the mortality rate for all ages was 1 per 200,000–300,000 cases, which was an improvement from 2 per 10,000 in the 1980s. A study from 2009 estimated that the mortality risk for surgical inpatients and adverse events of anesthesia was about 1 per 100,000 cases, and showed that the United States has experienced a 97% reduction in anesthesia-related death rates since the late 1940s.

While mortality rates have decreased for all age groups, the mortality rate for pediatric patients remains higher than adults. The mortality rate for pediatric patients in developed countries is estimated to be around 1 per 10,000 anesthetic cases. It is estimated that the pediatric mortality rate for developed countries was 0.41–13.4 per 10,000 anesthetics compared to 10.7–15.9 per 10,000 cases in the developing world. A study of over 90,000 patients from the Mayo Clinic showed that the mortality rate for all pediatric patients undergoing noncardiac surgery was 1.6 per 10,000 anesthetics, in contrast to cardiac surgery patients with an estimated rate of 115.5 per 10,000 anesthetic cases.

Perioperative cardiac arrest also occurs at a higher rate in pediatric versus adult surgical patients. The POCA registry comprised situational data on perioperative cardiac arrest events in 373 children from 1988 to 2005. The initial analysis found the incidence rate of anesthetic-related pediatric cardiac arrest to be 1.4 per 10,000 cases. When using the POCA criteria for deeming a cardiac arrest was related to anesthetic care, the Flick data showed an incidence rate of 1.5 per 10,000. Follow-up studies of the etiologic factors leading to events have changed over time, with cardiovascular events now overtaking respiratory events as a predominant factor.

The ASA Closed Claims Project database contains detailed information from 35 professional liability organizations on closed malpractice claims in the United States. For the reporting period of 1970–2001, there were 6894 closed claims, with 532 related to pediatric cases. The most common injuries leading to pediatric claims were death and brain damage, accounting for 41% and 21% of the claims, respectively. In the 1970s, respiratory events were the most common etiology of injury, accounting for 51% of precipitating events. However, by the 1990s, cardiovascular events have become the most common at 26%, compared to respiratory events at 23%. Improvements in ventilation and oxygenation monitoring, such as widespread adoption of end tidal capnography and pulse oximetry are associated with the relative decrease in the proportion of respiratory events.

In analyzing multiple studies regarding major morbidity and mortality events in pediatric anesthesia, major risk factors are age less than 1 year, ASA physical status 3 or higher, presence of congenital heart disease, and undergoing emergency surgery or cardiac surgery. Hypovolemia due to hemorrhage and laryngospasm are also significant precipitating events leading to poor outcomes.

Approximately 25%–45% of children presenting for elective surgery have a history of a recent upper respiratory tract infection (URI). ^, Performing surgery in the presence of a URI increases the risk of perioperative respiratory events such as laryngospasm, bronchospasm, desaturations, and breath-holding (25%–29% vs. 12% in well children). ^, Perioperative respiratory adverse events remain among the most common anesthesia-related critical events and are associated with 2.5 times higher odds of increased hospital stay after outpatient surgery, 30% higher hospital costs, and 58% higher indirect costs. Independent risk factors for perioperative complications when proceeding with URI symptoms include reactive airway disease, prematurity, airway surgery, intubation in children <5 years of age, and copious secretions with nasal congestion. Parental report of their child being ill has been predictive of laryngospasm.

A recent URI is the most common cause of cancellation or postponement of surgery in children. Postponement is usually 4–6 weeks due to potential residual airway hyperreactivity. Children under the age of four experience an average of eight URIs per year, with increased rates in winter months. The decision to cancel or postpone surgery should be made in conjunction with the surgeon and patient’s family, balancing the risk and benefit for each child.

Cancellation of surgery for children with mild URI symptoms (clear rhinorrhea, dry cough) is normally not necessary. Most children with mild-moderate URI symptoms can safely be cared for by tailoring their anesthetic management and optimizing them preoperatively to reduce stimulation of a hyperreactive airway.

Neonatal surgery is frequently performed on an urgent or emergent basis, with a higher mortality rate than in older children and adults. Increased survival in premature infants has led to more patients presenting for surgery with complex medical conditions unique to this population. Common comorbidities and pathologies involving premature patients include necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), retinopathy of prematurity, intraventricular hemorrhage, low birth weight, and pulmonary hypertension. Risk factors associated with perioperative complications in neonates include prematurity, congenital heart disease, BPD or serious respiratory conditions requiring ventilator dependance, NEC, sepsis, ICU admission, preoperative fluid bolus, and need for inotropic support.

Immature organ system development plays a significant role in anesthetic and surgical management plans of neonates. Vascular access can be particularly challenging in low-birth-weight patients. Smaller diameter endotracheal tubes are more susceptible to kinking and obstruction from secretions. Neonates are prone to barotrauma, oxygen toxicity, and pneumothorax from invasive ventilation techniques. Incomplete maturation of the liver and kidneys combined with differences in total body water cause altered pharmacokinetic effects in response to anesthetic medications. Cardiac output is highly dependent on heart rate, and maintenance of a normal heart rate is critical for these patients. Immaturity of neural control centers for respiration predispose neonates to apnea, particularly premature patients. Brain development is dependent on a continuous supply of glucose, and neonates have decreased bodily reserve to mobilize glucose, making them prone to perioperative hypoglycemia. Neonates have a higher oxygen consumption and decreased functional residual capacity (FRC), leading to rapid development of hypoxia in the perioperative setting. The anesthesiologist and surgeon should develop perioperative plans that consider these physiologic vulnerabilities and include operative location, intraoperative positioning, maintenance of homeostasis, and postoperative destination and monitoring.

Temperature control is critical to preventing hypothermia in infants. Common techniques include warming of the OR suite and aggressive use of convective/radiant heating devices, fluid warmers, and plastic drapes. To prevent hypoglycemia, dextrose-containing solutions are continued during the surgery and frequent monitoring of blood glucose is warranted. Blood loss and total volume of supplemental fluids should be closely monitored, as the total blood volume is small. The anesthesiologist must be vigilant for the development of hypovolemia, volume overload, dilutional anemia, and coagulopathy in these patients. The fraction of inspirated oxygen should be limited to the minimum necessary to maintain arterial oxygenation saturation (91%–95%) due to the contributory effects of hyperoxia and retinopathy of prematurity. Air bubbles in vascular lines must be avoided due to the potential presence of PDAs (patent ductus arteriosus) and intracardiac shunts.

The risk of postoperative apnea must be considered by the perioperative team for determining postoperative disposition and monitoring. Preterm patients are at an especially high risk for postoperative apnea, and the risk is proportional to the severity of prematurity, chronological age, and presence of anemia. Term infants less than 44 weeks postconceptional age (PCA) and preterm infants (born <37 weeks PCA) up to 54–56 weeks PCA are at risk of apnea. These patients require hospital admission and overnight cardiorespiratory monitoring. If apnea episodes occur, then prolonged monitoring should be extended. Institutional practice varies for discharge times after uneventful elective surgery in preterm patients, but most include postoperative admission requirements until 52–60 weeks PCA.

Approximately 40,000 children are born each year in the United States with congenital heart disease (CHD). Of those, 25% are critical and often require surgical intervention for survival. Data related to the risk of anesthesia for patients with CHD were reported in the Pediatric Perioperative Cardiac Arrest Registry (POCA) from 1994 to 2005. The registry showed that children with CHD were sicker compared to children without heart disease. It also revealed that children with CHD who experienced anesthesia-related cardiac arrest had a higher rate of mortality compared to those without CHD. Additionally, these arrests were more likely to occur in the general OR compared to the cardiac OR. This information led to the formation of dedicated pediatric cardiac anesthesia teams that provide care only to those children with CHD in both the general ORs and the cardiovascular surgery suite. There is a wide spectrum of severity of CHD, and a thorough preoperative workup and plan is critical for patient safety. Some of the key elements include reviewing any cardiac medications the patient is taking preoperatively and reviewing their current cardiac lesion, echocardiogram, and baseline health status. Most medications can be continued, but angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are held 24 hours prior to surgery to reduce the risk of profound hypotension with induction of general anesthesia.

From an anesthesiologist’s perspective, encountering an unanticipated difficult airway is one of the most stressful situations in clinical practice. Pediatric patients have higher rates of oxygen consumption and develop hypoxemia faster than adults. Furthermore, increased parasympathetic tone can lead to bradycardic responses to hypoxemia with subsequent cardiac arrest. Multiple attempts or significant force during laryngoscopy can also cause traumatic injury to the airway tissue.

A “difficult airway” includes difficulty in bag-mask ventilation or with obtaining a secure airway with an endotracheal tube (ETT). The rate of difficult mask ventilation in children is estimated to be 6.6%. A study by Heinrich et al. found the incidence of difficult laryngoscopy to be 1.35% overall, with the highest rate in children less than 1 year of age (4.7%). Oromaxillofacial and cardiac surgery were also associated with increased rates of difficult laryngoscopy. In the multicenter APRICOT (Anaesthesia PRactice In Children Observational Trial) study of patients under 15 years of age, the incidence of difficult intubation—defined as three or more intubation attempts—was 0.9%, with a rate of failed endotracheal intubation or failed laryngeal mask airway (LMA) insertion of 0.08%. For neonates and infants less than 60 weeks of age, the multicenter European NECTARINE (NEonate and Children audiT of Anaesthesia pRactice IN Europe) study showed a rate of difficult intubation of 5.8%. Of these cases, two-thirds were unanticipated difficult airways. Furthermore, 40% of the patients with a difficult airway had prolonged hypoxia, and 8% had bradycardia.

Numerous congenital conditions are associated with pediatric respiratory distress and concern with airway management. Some common etiologies are shown in Table 3.4 .

Careful preoperative evaluation for predictors of a difficult airway is an essential task in clinical practice. A medical history including the conditions listed above should raise the suspicion for difficulty in securing the airway. Reviewing prior anesthetic or intubation records is helpful in identifying both unsuccessful and successful strategies. Preparation and communication are vital to safe provision of anesthesia to these patients, including limiting procedures to institutions that have the clinical expertise and equipment to handle pediatric airway emergencies. Patients with a known difficult airway should not be scheduled for procedures with anesthesia in ambulatory surgery centers. In the OR, different sized ETTs, pharyngeal rescue devices, and LMAs should be immediately available. Advanced airway equipment should also be readily available, such as video laryngoscopes, flexible fiberoptic bronchoscopes, and the difficult airway cart. Communication with the surgeon about the concerns regarding the potential need for emergent surgical airway access should be relayed. Consultation with otorhinolaryngologists for assistance in particularly high-risk situations is helpful. They have valuable knowledge and technical expertise in dealing with airway pathologies as well as access to rigid bronchoscopy equipment.

The optimal approach for the known difficult airway is debated in pediatric anesthesiology. Awake and sedated techniques for intubation can be performed in appropriate patients, while maintenance of spontaneous ventilation during intubation under general anesthesia has been the most common traditional practice. When intubation is attempted with sedation, the rate of conversion to general anesthesia for intubation is 28%. The use of muscle relaxants is also controversial but can decrease the incidence of laryngospasm and hypoxemia compared to spontaneously ventilated patients with a difficult airway. When an unanticipated difficult airway is encountered, the important themes are calling for assistance, having a comprehensive understanding of the difficult airway algorithm, immediate access to airway rescue equipment, and rapid mobilization of additional specialists with proficiency in advanced airway techniques.

It is also important to document the degree of difficulty and equipment used in the anesthetic record or in a separate note for nonoperative intubations. This will be helpful for future situations in which intubation is required, not only for anesthesiologists. It is also important to inform the family of any difficult airway experience and potentially provide a letter describing the circumstances of airway difficulty. We have a difficult airway registry in the electronic medical record in which a pop-up screen appears when opening the chart, notifying all clinicians of the serious situation, and guiding not only intubation management but also use of any sedative or respiratory depressant medications. Development of multidisciplinary pediatric difficult airway programs can decrease the risk of emergent difficult airway calls while increasing the likelihood of first-attempt success.

Down syndrome (DS) or trisomy 21 is a genetic disorder with an incidence of 1 in 600 to 1 in 1000. Characterized by developmental delays and congenital abnormalities, DS presents the anesthesia team with numerous challenges during the perioperative period.

The most common congenital anomaly associated with DS is CHD, which is present in over 40% of patients. Most common heart defects include atrioventricular canal defects, ventricular septal defects, atrial septal defects, PDA, and tetralogy of Fallot. The second most common anomaly is GI defects, with duodenal atresia being the most common. Other common anomalies involve the musculoskeletal, respiratory, and urinary systems.

All patients with DS should have a comprehensive preoperative assessment. Many patients may have a complex cardiac history, and a preoperative ECG and/or echocardiography may be warranted. Preoperative respiratory assessment and optimization are also needed as many patients with DS have obstructive sleep apnea, which may require postoperative hospital admission for extended observation. Preoperative airway evaluation is also needed as patients with DS have many facial features that can make management of their airway challenging.

On the day of surgery, a discussion with the parents and patient may help determine the best and safest way to induce anesthesia. Preoperative anxiolysis with oral midazolam may be beneficial but is not always necessary depending on the degree of intellectual disability. Using Child Life services is recommended, and parental presence at induction may be helpful.

In patients with DS, an inhalational induction with sevoflurane, with or without nitrous oxide, is frequently performed. Patients with DS with or without CHD are more likely to develop bradycardia and/or a junctional rhythm with hypotension during induction, and thus a gentle stepwise increase in sevoflurane concentration and quick IV line placement are prudent. Typically, bradycardia will subside with turning off sevoflurane plus stimulation such as IV placement, but atropine and epinephrine should always be available. In addition to sevoflurane, patients with DS may be more likely to develop bradycardia in response to dexmedetomidine. A difference in the development of the autonomic nervous system in patients with DS is thought to contribute to this occurrence.

Common facial and airway features that have anesthetic implications include midface hypoplasia with a narrowed nasopharynx, small mouth, macroglossia, and adenoid/tonsillar hypertrophy. These features increase the incidence of obstructive sleep apnea in patients with DS. Under anesthesia, these patients may be challenging to mask-ventilate and an oral airway may be needed. Up to 15% of patients with DS may have atlantoaxial instability, which needs to be taken into consideration when manipulating the airway. During direct laryngoscopy, an effort should be made to keep the head and neck in a neutral position to avoid excessive flexion or extension of the neck. Patients with DS also have increased rates of laryngomalacia and subglottic stenosis. The anesthesia team should have a low threshold for using advanced airway equipment like a video laryngoscope to assist with intubation. A smaller than predicted ETT may be needed, and patients with DS have an increased incidence of postoperative stridor requiring racemic epinephrine.

A tracheoesophageal fistula (TEF) is a common congenital defect that connects the trachea and esophagus. Approximately 20% of patients with a TEF also have CHD; most commonly a VSD. An echocardiogram must be performed prior to surgical repair to define any possible congenital heart defects.

Airway management is one of the most important aspects for safely operating on these patients. The ETT position depends on the type of TEF; this consideration should be discussed between the anesthesiologist and surgeon preoperatively. Rigid bronchoscopy is often performed at the beginning of the surgical repair to better define the location of the fistula, evaluate cord function, and rule out second fistulae. One of the main anesthetic goals is to provide adequate oxygenation and ventilation while reducing the amount of gastric distention and yet allow an adequate operative field in the thorax. Typically, a balanced anesthetic is used for this procedure, which includes the use of inhaled anesthetics, IV anesthetics including opioids, and muscle relaxants.

A congenital diaphragmatic hernia (CDH) can lead to the displacement of the lungs, heart, and other contents of the mediastinum. A thorough preoperative workup is necessary and should include basic laboratory work, a chest X-ray, and an echocardiogram. Patients are at an increased risk of having a pneumothorax (usually not due to ongoing air leak and not usually physiologically significant) and decreased pulmonary compliance. Often, patients with these issues are intubated shortly after birth, and some even require the use of ECMO and high-frequency oscillatory ventilation (HVOC). The timing of when to operate depends on the patient’s status, so it is important to consult with the physician anesthesiologist before proceeding.

Patients with a CDH are at increased risk of pulmonary hypertension and many other derangements such as acidosis, hypoxemia, and hypercarbia. General anesthesia is typically maintained using a balanced anesthetic technique similar to that used with patients with a TEF. Many patients will require the placement of an arterial line to monitor blood gas levels during the operation. Anesthetic goals include maintaining adequate oxygenation and ventilation in addition to correcting and maintaining possible metabolic changes. Avoiding aspiration is another key goal during these procedures. As with TEF repairs, regional anesthetic techniques such as an epidural can be used to reduce opioid consumption and can help with pain control into the postoperative period. Postoperatively, these patients are normally returned to the ICU intubated and sedated.

Mediastinal masses can be in the anterior, middle, or posterior portions of the mediastinum, yet tumors in the anterior portion are the most challenging to manage from an anesthetic standpoint due to an increased risk of cardiopulmonary collapse. In the pediatric population, lymphomas are the most common cause of anterior mediastinal masses. A multidisciplinary well-developed plan tailored to the individual is the best way to ensure safe care prior to delivering an anesthetic.

Children with undiagnosed anterior mediastinal masses should be approached with a multidisciplinary team including oncology, anesthesia, interventional radiology, surgery, and a pediatric intensivist. The ECMO team is also included if there is concern for potential ECMO. Key topics include:

• 1.

  The diagnostic procedure needed and the best route for biopsy (open vs. core biopsy).

• 2.

  The need for central venous catheter or peripherally inserted central catheter (PICC) line placement.

• 3.

  The need for a bone marrow biopsy or lumbar puncture.

• 4.

  The optimal timing of the procedure for safety purposes (avoid after hours or weekends).

• 5.

  The in-house presence of the pathologist at the time of biopsy.

Goals include achieving a diagnosis and initiation of therapy within 48 hours of hospital admission and the need for only one anesthetic.

The CXR-derived MMR (mediastinal mass ratio) is the width of the mass divided by the width of the thoracic cavity; an increased MMR has been associated with increased complications during an anesthetic. A chest CT will show the size and location of the mass and whether a mass effect is causing narrowing of the trachea and/or bronchial tree, compression of the great vessels, pericardial effusions, and other abnormalities. An echocardiogram should be obtained to check for left ventricular and right ventricular function, pericardial tamponade, pulmonary blood flow, and other changes due to mass effect. Historically, pulmonary function tests have been included in the initial workup, but they do not assist with preoperative planning for anesthesia.

During the physical exam, it is important to note if the patient has shown recent changes in voice/hoarseness/stridor, shortness of breath/coughing, edema, orthopnea, and recent syncope. Any of these symptoms can indicate respiratory or cardiovascular compression by the mass, yet their absence does not necessarily decrease the risk of cardiopulmonary collapse with anesthesia. Systems have been proposed to stratify the anesthetic and intraoperative risks based on presenting signs and symptoms for pediatric patients, but regardless of risk, each anesthetic needs to be tailored to the patient and procedure. The importance of the multidisciplinary team determining the safest pathway for diagnosis and treatment cannot be overstated.

The type of anesthetic delivered depends on the procedure as well as the patient and can range from light sedation to general anesthesia with an ETT. In any case, the anesthesiologist must be prepared for potential cardiopulmonary collapse. To help prevent respiratory collapse from airway compression, the goals of the anesthetic may include maintaining spontaneous ventilation and avoiding ETT placement, as positive pressure ventilation causes an increase in intrathoracic pressure, which may worsen the compression of the mass. Administering muscle relaxants may lead to loss of any underlying muscle tone and may also worsen the mass effect. Normal respiratory changes with general anesthesia, such as a decrease in FRC and increases in ventilation/perfusion mismatch, may all be worsened in these patients. If respiratory collapse does occur, options include changing the patient position from supine to sitting up or lateral/prone and splinting the trachea open by advancing an ETT past the area of collapse, inserting an armored/reinforced tube, or performing a rigid bronchoscopy. If a muscle relaxant has been used, a reversal agent should be administered in an effort to get the patient spontaneously breathing again. Advanced airway equipment and ENT should always be readily available when anesthetizing these patients.

Cardiovascular collapse typically occurs due to compression of venous blood return to the heart, decreasing cardiac output, which may be exacerbated by induction of anesthesia. If cardiovascular collapse occurs, options include changing patient position, emergent thoracotomy or sternotomy with tumor debulking, and ECMO. An ECMO decision is ideally made preoperatively since using it as a rescue option may be infeasible. If ECMO is thought to be a strong possibility, it is recommended that femoral sheaths be inserted prior to induction of anesthesia and an ECMO machine be primed in the room with a perfusionist—or that ECMO be started prior to induction of anesthesia.