conditions for a child undergoing sedation, it is important to understand the definitions pertaining to level of consciousness, as well as having the ability to rescue a child from a deeper level of sedation than was intended.
Box 4.1 ASA physical status classification
Class I A normal healthy patient
Class II A patient with mild systemic disease (e.g., controlled reactive airway disease)
Class III A patient with severe systemic disease (e.g., a child who is actively wheezing)
Class IV A patient with severe systemic disease that is a constant threat to life
Class V A moribund patient who is not expected to survive without the operation
Assessing risk in the pediatric patient
The Pediatric Sedation Research Consortium (PSRC) is a collaborative of 40 hospitals and universities in the United States and Canada with a mission dedicated to understanding and improving the process of pediatric sedation and sedation outcomes. Member institutions prospectively enroll pediatric patients receiving sedation for all procedures outside the operating room, and the data are entered into a central database. This rich database has contributed a great deal to pediatric procedural sedation literature over the last 10 years.
Predictors of adverse events for GI procedures
In 2015 a review was performed to assess the predictors for adverse events during esophagoduodenoscopy (EGD) and colonoscopies for pediatric patients. 12 030 procedures were examined: 7970 EGD, 1378 colonoscopies and 2682 were a combination of both. The majority of adverse events were desaturation (1.5%) and airway obstruction (1%); there were no deaths or CPR administered. This analysis revealed that ASA greater than or equal to II, receiving both procedures, obesity, presence of lower airway disease, and age were independent predictors of adverse events. The highest occurrence of adverse events (15%) occurred in those less than 1 year of age, with an occurrence of 8% in those between 2 and 5 years. While the adverse events did not result in permanent consequences, the findings do support a case for preemptive airway control with endotracheal intubation in young children undergoing GI procedures.
Obesity
In 2015 the PRSC database was examined to quantify the effect of obesity on rates of adverse events. The study included 5153 patients with a body mass index greater than the 95th percentile, and compared them to 23 639 nonobese patients. Comparison of the groups revealed that obese children have a higher incidence of adverse respiratory events and resulting airway interventions during procedural sedation (odds ratio [OR] 1.49, 95% confidence interval [CI] 1.31–1.7). The obese group had a higher incidence of the need for bag valve mask (BVM), use of nasopharyngeal (NP) airway, and head repositioning (OR 1.56, 95% CI 1.35–1.8). These findings provide further supporting evidence that obesity is an independent risk factor for adverse events, as well as the need for airway intervention.
NPO
Historically, the issue of fasting intervals before an elective procedure has generally followed those for elective anesthesia set forth by the ASA, yet recently these have come into question. Current ASA NPO guidelines state six hours is sufficient time for most foods, including infant formula, eight hours for a full meal and 4–6 hours for breast milk and clear liquids.
In 2016 the PRSC examined the effect NPO status had on aspiration, as well as major complications such as cardiac arrest or unplanned hospital admission. A total of 139 142 procedural sedations were reviewed. NPO status was known in 107 947 cases; 25 401 (23.5%) were not NPO. Aspiration occurred in eight of 82 546 (0.97 events per 10 000) who were made NPO per ASA guidelines versus two of 25 401 (0.79 events per 10 000) who were not NPO (OR 0.81, 95% CI 0.08–4.08; p = 0.79). Major complications occurred in 46 of 82 546 (5.57 events per 10 000) versus 15 of 25 401 (5.91 events per 10 000) (OR 1.06, 95% CI 0.55–1.93; p = 0.88). Overall, there were 0 deaths, 10 aspirations, and 75 major complications. Multivariate analysis revealed NPO status is not a predictor of either aspiration or experiencing a major complication.
Upper respiratory infection
The presence of URI is ubiquitous in pediatrics. The decision to cancel a procedure due to an upper respiratory infection can have impacts on patient care, as well as logistical problems for healthcare providers and parents. There are numerous studies suggesting that when anesthesia is administered to a patient with an active or recent URI, there is an increased frequency of airway events such as coughing or laryngo/bronchospasm.
In 2012 the PRSC evaluated this question. A total of 83 491 sedations were included; 70 830 without URI were compared to 13 319 patients with either recent or active URI, classified as having either thin or thick colored secretions. Data were examined for airway‐related adverse events.
Occurrence of adverse events increased progressively from 6.3% for those with no URI, 9.3% for recent URI, 14.6% for URI with thin secretions, to 22.2% for those with URI and thick secretions (p < 0.001). The most common events were airway obstruction, oxygen desaturation, snoring, cough that interfered with the procedure, secretions requiring suctioning, stridor, or wheezing. The need for airway interventions followed an identical pattern, increasing from no URI through URI with thick secretions. The most common interventions were providing BVM, suction, or repositioning. There were no emergent airway interventions, unplanned admissions, or administrations of CPR.
The data suggest that in addition to a recent or active URI, the nature of the secretions is significant in assessing risk, with thick secretions carrying the highest risk. While the findings revealed a statistically significant difference, the nature of the events and consequences may not be clinically significant. Events such as laryngospasm, aspiration, emergent intubation, unplanned admission, and emergent call for anesthesia all remained <1% regardless of URI status. While there is a higher risk for adverse events in children with recent or active URI with thick secretions, these must be balanced against the acuity of the patient’s condition and the urgency of procedure.
Preparation
A thorough presedation assessment is crucial in order to identify patients at risk for adverse events. Sedation for endoscopy must be tailored for each individual, yet preparations should be approached in the same stepwise fashion for every patient. The components of a presedation evaluation should include (i) informed consent, (ii) verbal and written instructions for postprocedure issues, (iii) the child’s medical history, (iv) physical exam, and (v) a risk assessment.
Informed consent specific to the procedural sedation must be obtained and documented in accordance with institutional guidelines. Verbal and written instructions to the parent or guardian should include the objectives of the sedation as well as anticipated effects during and after the procedure. Patients must know whom to contact after the procedure if any medical issue arises after being discharged from the hospital
The medical history should focus on any current or past medical illnesses affecting the cardiovascular, respiratory, hepatic or renal systems, which may affect the child’s response to the medications chosen. Consultation with a pharmacist may be necessary when there is a concern for drug interaction. Previous experiences with procedures should be elicited in order to uncover events that the child may be predisposed to, and a family history regarding anesthesia should be obtained. A thorough history of allergies to any medications or foods is important. As an example, propofol is manufactured in an oil‐in‐water base with egg and soybean oil, and therefore is contraindicated for use in a patient with egg or soybean allergy.
The physical exam must include a complete set of vital signs, which includes temperature, heart and respiratory rate, blood pressure, and pulse oximetry. A current weight is needed for appropriate medication dosing. Particular attention must be paid to the oropharynx for findings such as