Obese kids at higher respiratory risk post-surgery
By Anthony J. Brown, MD
NEW YORK (Reuters Health) - Obese children who undergo elective surgery typically have more additional medical conditions than their normal-weight peers do and are also at greater risk of developing adverse respiratory events after the procedure, U.S. researchers report.
"Many anesthesiologists may suspect that obese children have a 'rockier' anesthetic course than normal-weight children," lead investigator Dr. Alan R. Tait told Reuters Health. "We have now confirmed that these children do indeed have an increased risk of adverse events."
The study findings also show the obese children tend to have more illnesses than other children do "which, in and of themselves, may increase their anesthetic risk," he added.
Tait, a researcher at the University of Michigan Health System in Ann Arbor, pointed out that many studies have examined the impact of obesity on the surgical outcomes of adults, but relatively few studies have covered this topic in children.
The new findings are especially relevant because of the increasing prevalence of obesity in the U.S. and in many other countries, according to their report in the current issue of the journal Anesthesiology.
The researchers examined the number of adverse respiratory events that occurred in 2,025 children undergoing elective surgery, excluding heart surgeries. There were 1,380 normal-weight children, 351 who were overweight, and 294 children who were obese.
Several other conditions were more common in obese children than in normal-weight children, including sleep apnea, asthma, high blood pressure and type II diabetes, the report indicates.
After other possible risk factors were eliminated, the investigators found that obesity was associated with overall critical respiratory complications including increased difficulties in mask ventilation during surgery, airway obstruction and major loss of oxygen concentration in the body.
Other independent risk factors for respiratory problems included pre-existing sleep apnea or asthma, young age and having a procedure that involved the airway.
Tait said his team was "surprised that obstructive sleep apnea was identified as a risk factor for adverse events in these children independent of obesity. Again, this has been demonstrated in adults but has been less well documented in children." He added that his group may investigate this finding further in additional studies.
Tait emphasized that anesthesiologists should be aware of and understand the pre-existing conditions and adverse respiratory events that may affect obese children so that they can "anticipate, recognize, and treat these events should they occur."
SOURCE: Anesthesiology, March 2008.