Carboxyhemoglobin and Methemoglobin as Markers of Postoperative Pulmonary Complications

Abstract

Introduction: The inhalation of tobacco smoke can substantially raise the level of carboxyhemoglobin in the blood. Determination of the level of carboxyhemoglobin and methemoglobin can identify patients with increased risk for development of postoperative pulmonary complications. Material and Methods: Thirty patients scheduled for elective urologic surgery under general endotracheal anesthesia were allocated in two groups (n = 15 each). The study group comprised patients who were smoking cigarettes or tobacco pipe, while the control group included non-smokers. In both group's carboxyhemoglobin and methemoglobin levels were determined preoperatively, after preoxygenation, and one hour after completing the anesthesia. Postoperative pulmonary complications were assessed and recorded during the period of hospitalization. Results: The average values of carboxyhemoglobin between the two groups were statistically significantly different. Postoperative carboxyhemoglobin was higher in smokers compared to control non-smokers group (p = 0.000). On the other hand, methemoglobin was higher in the control non-smokers group compared to smokers, but without statistical significance (p = 0.88). Regarding postoperative pulmonary complications, 13.3% of the patients in the control non-smokers group and 26.6% of the patients in smokers group had pulmonary complications. Conclusion: In our sample there was a difference between the incidence rates of postoperative pulmonary complications; however, we cannot confirm the hypothesis that carboxyhemoglobin and methemoglobin can serve as predictors for postoperative pulmonary complications.

Prediction Value of Oxygenation Index as Predictor for Postoperative Pulmonary Complications in Urologic Surgery

“…Identifying patients with an increased risk of development of PPC can lead to improved preoperative evaluation, perioperative management and postoperative therapy. Risk factors for PPC can be classified into patientsrelated and surgery-related risk factors (3).…”