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Weight: 21 kg
Height: 110 cm
BP: 95 / 60
HR: 100 bpm
RR: 26 breaths/min
SpO2: 98%
Cardiac: No visible cyanosis, clubbing, or peripheral edema. JVP ~2 cm ASA. PMI at 5th intercostal space at midclavicular line. Normal S1 S2 with grade 3 holosystolic systolic murmur heard at left lower sternal border. Radial, femoral, dorsalis pedis and posterior tibial pulses 2+ bilaterally and symmetric.
Respiratory: Breathing through mouth at rest. No use of accessory muscles of respiration. Grade 3 Brodsky tonsils. Chest wall expansion is symmetric bilaterally. Lungs clear to auscultation with equal air entry bilaterally, no crackles or wheeze.
Neurological: Alert and responsive. Cranial nerves demonstrate no focal abnormalities. Generalized hypotonia noted. Decreased resistance to passive ROM in upper and lower extremities bilaterally. Biceps, triceps, brachioradialis, patellar, achilles reflexes +1 bilaterally. Finger-to-nose mild dysmetria. Rapid alternating movements mildly slowed. No tremor or ataxia noted. Light touch, pain, and proprioception sensation intact and symmetric in upper and lower extremities.
MSK: No neck pain, radicular symptoms, or gait abnormalities suggestive of atlantoaxial instability. Normal cervical ROM.
Pediatric patients are at higher risk of O2 desaturation during apnea or hypoventilation due to their unique physiology (Trachsel et al., 2022):
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Higher metabolic rate = higher O2 demand
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Lower FRC = less O2 capacity between breaths
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Greater lung compliance = greater negative intrathoracic pressure = higher risk of atelectasis
Anatomically, children have a relatively larger head, shorter trachea, larger tongue, and their larynx is positioned more superior and anterior (Toronto Notes, 2023). The narrowest part of the pediatric airway is at the cricoid, as compared to the glottis in adults (Toronto Notes, 2023).
Hypoxemia in pediatric anesthesia is defined as an SpO2 <90%, a drop in SpO2 by 5%, or PaO2 < 60 mmHg (Gaba et al., 2015).
Developmental differences in neurologic and autonomic physiology have important implications for our management. At birth, parasympathetic fibres are relatively mature, whereas sympathetic fibers do not fully mature until approximately 4 - 6 months of age. Thus, there is an autonomic imbalance during the first 6 months of life. Although this is not directly relevant to our five-year-old patient, it remains a critical consideration when caring for younger infants, as it can significantly influence intraoperative hemodynamics.
There are also important age-related differences in anesthetic requirements between pediatrics and adults. The minimum alveolar concentration (MAC) of volatile anesthetic agents is higher in infants and young children compared to adults (Mapleson, 1996). This means that a greater concentration of inhaled anesthetic is required to prevent movement in response to surgical stimulus in 50% of pediatric patients than in adults. This is thought to be due to greater CNS excitability and neurohormonal factors largely due to greater CNS excitability and higher metabolic rates in pediatric patients (Coté et al., 2009).
Additionally, perioperative stress may precipitate seizures, with children being particularly susceptible to this effect (Voss et al., 2008). This risk is especially relevant in patients with Trisomy 21 (Bull et al., 2022). Some commonly used anesthetic drugs (etomidate, propofol, and inhaled anesthetics enflurane + sevoflurane) (Voss et al., 2008) can lower seizure threshold.
Children, especially those with congenital heart disease, have limited myocardial contractile reserve, and are more dependent on HR to maintain CO (recall CO = HR x SV). This is particularly important in our case where our patient has Trisomy 21. Congenital heart defects are present in 40-50% of children with Trisomy 21, most often atrioventricular septal defects and ventricular septal defects (Bull et al., 2020). This impacts our intraoperative hemodynamics, especially if pulmonary hypertension is present. It is also important to note that children have a higher baseline HR and lower BP (Nasr et al., 2020).
Another important consideration is obesity, as it increases the risk of airway collapse, hypoventilation, and difficult mask ventilation/intubation. This is an important consideration in our case as rates of obesity are much higher in children with down syndrome, and anesthetic dosing may need to be tailored to ideal body weight (Basil et al., 2016).
Pediatric Fasting Guidelines:
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6 hours for solids
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4 hours for infant formula
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3 hours for breast milk
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1 hour for clear liquids
Correct. Especially during induction, emergence, and recovery when airway tone and respiratory drive are reduced
Age: 5
Gender: M
Indication for surgery: OSA
Surgical / anesthetic history: None
Family history: No history of malignant hyperthermia or pseudocholinesterase deficiency
Medications: None
Allergies: NKDA
Review of systems:
Neurologic, cardiac, and respiratory systems are most important as part of your pre-anesthetic evaluation. Anesthetic drugs primarily act on the CNS, altering consciousness, reflexes, and respiratory drive. Additionally, neuromuscular disorders can affect a patient's response to muscle relaxants and postoperative ventilation.
Anesthetic drugs can cause myocardial depression, vasodilation, and arrhythmias, all of which stress the cardiovascular system. Reviewing cardiac history helps assess the ability of the patient to tolerate hemodynamic changes during induction and surgery, as well as their risk of ischemia, heart failure, or arrhythmia.
Of course, airway management and ventilation are central to anesthesia. Many anesthetic agents depress respiration and blunt protective airway reflexes. Pre-existing respiratory disease increases the risk of difficult airway, hypoventilation, hypoxia, and postoperative respiratory complications.
If time permits, a quick review of systems of gastrointestinal, renal, hematologic, musculoskeletal, and endocrine systems may also provide helpful information such as aspiration risk, bleeding risk, airway positioning considerations, and metabolic stability.