Effect of carboxyhemoglobin on postoperative complications and pain in pediatric tonsillectomy patients

Summary Background Carbon monoxide (CO) is a product of burning solid fuel in stoves and smoking. Exposure to CO may provoke postoperative complications. Furthermore, there appears to be an association between COHb concentrations and pain. We thus tested the primary hypothesis that children with high preoperative carboxyhemoglobin (COHb) concentrations have more postoperative complications and pain after tonsillectomies, and secondarily that high‐COHb concentrations are associated with more pain and analgesic use. Methods 100 children scheduled for elective tonsillectomy were divided into low and high carbon monoxide (CO) exposure groups: COHb ≤3 or ≥4 g·dl−1. We considered a composite of complications during the 7 days after surgery which included bronchospasm, laryngospasm, persistent coughing, desaturation, re‐intubation, hypotension, postoperative bleeding, and reoperation. Pain was evaluated with Wong‐Baker Faces pain scales, and supplemental tramadol use recorded for four postoperative hours. Results There were 36 patients in the low‐exposure group COHb [1.8 ± 1.2 g·dl−1], and 64 patients were in the high‐exposure group [6.4 ± 2.1 g·dl−1]. Indoor coal‐burning stoves were reported more often by families of the high‐ than low‐COHb children (89% vs 72%, P