For children undergoing general anesthesia for surgery or other procedures, the risks of several adverse respiratory (breathing-related) events are greater if the child has recently had a cold or other upper respiratory infection (URI).

The November issue of the journal Anesthesiology presents the first large study to look at how recent URIs affect the risk of adverse respiratory events in children receiving anesthesia using the laryngeal mask airway (LMA). The results suggest that, although the overall risk is low and serious complications are rare when anesthesia is delivered in children via an LMA, waiting two weeks after a URI may make anesthesia even safer. “Our results will help anesthesiologists in planning the anesthesia management of children with recent upper respiratory tract infection,” comments Dr. Walid Habre of University Hospitals of Geneva, Switzerland, one of the study authors.

Over a five-month period, the researchers asked parents of children undergoing surgery to provide information on any recent URIs, such as colds, sinusitis, or tonsillitis. All of the children were under general anesthesia (asleep) for their procedures. Airway management was achieved via an LMA—a device sometimes recommended as an alternative to a standard tracheal (windpipe) tube for anesthesia in children with recent URIs.

According to the parents, 27 percent of children had had a URI in the previous two weeks. Children with recent URIs were about twice as likely to develop certain adverse respiratory events.

The most common event was a decrease in the blood oxygen level, called desaturation, during anesthesia. Overall, 20 percent of children had episodes of desaturation requiring oxygen administration in the recovery room. Although these events were more frequent in children with recent URIs, they were no more severe.

Children with URIs also had a greater rate of a respiratory event called laryngospasm, which is a sudden closure of the vocal cords. In severe cases, laryngospasm can cause serious breathing problems. However, none of the children in the study had severe laryngospasm.

Children with recent URIs were also at almost double the risk of problems with coughing after their procedure.

All respiratory events were more common in younger children and in children undergoing surgery on the ear, nose, and throat. Adverse events were also more frequent when more than one attempt was needed to insert the LMA device in the mouth.

Previous studies have shown an increased risk of respiratory events in children with recent URIs. These events occur because the airway is more sensitive than usual after a cold or other URI. Because it does not pass through the vocal cords, the LMA may be used to maintain the airways and deliver anesthesia to children with recent URIs to reduce the risk of laryngospasm and other respiratory events.

Anesthesiologists balance the risks of proceeding with surgery in children with a recent URI with the economic and emotional costs of canceling surgery. The risks of proceeding with surgery are not well-known due to limited evidence on how long one must wait after a URI for the risk to decrease to normal.

The results suggest that if an LMA is used as the breathing device, the risk of breathing-related adverse events is greater in children who have had a URI within the two weeks before surgery. The researchers emphasize that the overall risk is low, and that all of the events in the study were easily managed, with no lasting effects. “Our study may help parents to better understand why anesthesiologists may prefer to postpone anesthesia for at least two weeks in children with recent URI—in order to decrease the incidence of perioperative respiratory adverse events,” says Dr. Habre.

For additional information on this study, go to http://www. anesthesiology.org.

Founded in 1905, the American Society of Anesthesiologists is an educational, research and scientific association with 41,000 members organized to raise and maintain the standards of the medical practice of anesthesiology and improve the care of the patient.

Source: American Society of Anesthesiologists (ASA)