A 3-year-old male presented for an elective circumcision. He was an ex-32-week preemie with reactive airways and a recent URI requiring nebulized albuterol. The URI resolved 3 weeks ago, and he took a course of antibiotics. PO midazolam was given in pre-op holding area for anxiolysis, and he was calm on arrival to OR. Mask induction was performed, initially 70/30 N2O/O2, then sevoflurane 8%. A rotating dental resident held the face mask. I noted obstruction, instructed rotator to perform jaw thrust and a second resident to turn the APL valve to 5 cm H2O. The EtCO2 tracing went flat, I took over bag mask ventilation. I was able to give 2-3 small breaths with APL at 30 cm H2O with FiO2 100%, but the patient then vomited abaout 5 mL milky fluid. I instructed the resident to give 1 mL succinylcholine/atropine IM as the SpO2 continued to drop and simultaneously called for help. PIV placed by help as I intubated with a 4.0 cuffed ETT. +EtCO2 & BBS= but significant leak. Rocuronium I.V. given. I ventilated until SpO2 > 96%, then DL again to change the ETT to 4.5 cuffed tube. Leak at 20 cm H2O, +EtCO2, BBS=. An orogastric tube was placed to suction stomach, and the ETT was suctioned (no secretions). The case proceeded uneventfully. Caudal deferred, surgeon performed penile block. At the end of case, albuterol MDI 8 puffs were given through the ETT and NMB reversed. Nares & ETT then suctioned (separate suction catheters) with copious yellow-green secretions. Slow, controlled extubation with patient awake. Pt transported to PACU with SpO2 & HR monitoring and O2 via FM. Mother debriefed afterward and given instructions to return to hospital if patient with worsening cough/fever/lethargy at home.

There is a lot to unpack in this report, which touches on so many common and critical events in pediatric anesthesia and on general issues about teaching in the OR (the reporter notes that the inexperience of the rotating dental resident and the insufficient definition of roles probably played a part in the evolution of the event). Quick and effective action on the part of the attending anesthesiologist resulted in a good outcome for this patient, but it raises many issues worthy of consideration. We will confine this discussion to a single important and frequently occurring topic – how to handle an upper-respiratory infection in a child presenting for surgery and how this is a paradigm for the enigma of how to act when the data are ambiguous or uncertain.

The conundrum of the child with a recent upper respiratory infection (URI) presenting for elective surgery is well known to anyone who anesthetizes children. The prevalence of URI in children coming for elective surgery is quite high – one recent study of day care enrollees found that URI symptoms were present in 11% of children at any time. Most children will have a URI once every 10 weeks, an average of five per year, so we can expect that many of our patients will either have, or have recently had, a URI (Clin Infect Dis 2008;46:815-23). Prospective studies are largely observational in nature and thus unavoidably tainted by selection bias because ethical concerns preclude the ability to randomize the subjects to “cancel” or “proceed,” and the sicker patients are generally cancelled even before they get to be studied. These studies still have much to teach us about how to make decisions because they have defined factors that are associated with an increased incidence of adverse respiratory events, including hypoxia, cough, laryngospasm, and breath holding (Anesthesiology 2001;95:299; Paediatr Anaesth 2001;11:29-40).

There are numerous important factors that may increase risk in the child with URI, several of which were present in our case report. Ex-premature infants are at greater risk, even when they have no overt symptoms of respiratory disease, as are children with underlying respiratory diseases such as asthma and bronchopulmonary dysplasia. Endotracheal intubation introduces more risk than does an LMA, which in turn is a greater risk than a non instrumented airway. The operation matters, too – surgery on the airway or affecting the airway is a greater risk than peripheral surgery. Parental smoking, which exposes the child to airway irritants, and unhealthy air quality, particularly the small particulate pollution characteristic of wildfire smoke, increase the risk and incidence of adverse airway events. Indeed, even children without underlying respiratory disease or without URI are more likely to have adverse respiratory events during and after anesthesia with these exposures. The nature of the symptoms of the URI (such as thick copious secretions or severe nasal congestion) is an additional parameter to consider.

Importantly, animal and human studies report that recent resolution of symptoms is not sufficient to ensure that increased airway reactivity has abated. If a child is deemed too ill to proceed with anesthesia, it is best to wait between two and four weeks to reschedule (even longer might be better, as animal studies show increased airway reactivity for eight weeks after infection; but there is a high likelihood that by then the child might have contracted another cold!). One large prospective observational study found equally increased rates of adverse respiratory events in children with either an active or recent URI compared with well children (Anesthesiology 2001;95:299-306). Although another retrospective analysis did not detect a correlation between recent URI and adverse events, most expert opinion sides with the first study, which has fewer methodological limitations (Paediatr Anaesth 2001;11:29-40).

Despite all these data, the preponderance of evidence suggests one can proceed cautiously for an average, mild URI in a nontoxic child, sometimes modifying the anesthetic technique. For example, using an LMA instead of an endotracheal tube and adding a regional block to facilitate this or planning a deep extubation when possible might reduce risk or the severity of events (Anesth Analg 1991;72:282-8; Anesth Analg 2005;100:59-65). Adverse respiratory events with an LMA are still higher in children with colds than without them, however, so this is not a panacea (Anesthesiology 2007;107:714-9). Although coughing, bronchospasm, transient desaturation, and breath holding occur more frequently in these patients, the events that occur are largely manageable and outcomes are usually good. The key is heightened vigilance and anticipation of the adverse events that might occur.

When deciding whether to proceed, medical issues are always paramount, yet one should not discount the potential toll that cancellation takes on families (Clin Anesth 1997;9:213-9). They may have had to arrange for child care for other children, taken days off from work, or travelled considerable distances.

A final important consideration is that rare, serious events still may occur (Anesth Analg 2005;100:59-65). Undiagnosed post-viral myocarditis in the weeks following a URI can be unmasked during anesthesia, especially during inhalation induction. Children with this condition can develop dysrhythmias, ECG evidence of ischemia, and hypotension, all signs that should serve as a warning to the anesthesiologist to promptly abort the procedure and seek cardiac consultation. In rare cases, children with URI symptoms may have a serious lower respiratory tract infection that blossoms or is unmasked by intubation. Acute respiratory failure is a rare but known event in these conditions.