PREOPERATIVE PULMONARY-FUNCTION EVALUATION FOR LAPAROSCOPIC CHOLECYSTECTOMY

Objective: Hypercarbia with respiratory acidosis is a recognized compl ication of laparoscopic cholecystectomy. This study was performed to i dentify preoperatively those patients who may develop hypercarbia and acidosis during the procedure. Design: Retrospective analysis of preop erative variables. Patients: Thirty-one consecutive patients underwent laparoscopic cholecystectomy at one institution who were receiving bo th preoperative pulmonary function tests and arterial blood gas analys is. Results: More than 80 demographic, laboratory, and perioperative v ariables were entered into a univariate analysis to identify predictor s of intraoperative acidosis (pH, <7.35). Patient age, duration of the procedure, and preoperative blood gas values were not predictors of i ntraoperative acidosis. Several univariant predictors for patients exp eriencing carbon dioxide pneumoperitoneum-induced hypercarbia were ide ntified; these included an elevated American Society of Anesthesiologi sts classification and significant decreases in forced expiratory flow at 25% of maximum, maximal forced expiratory flow, maximal voluntary ventilation, vital capacity, inspiratory capacity, and diffusing capac ity of the lung for carbon monoxide, Conclusions: This study suggests that neither age nor preoperative arterial blood gas values are predic tive of intraoperative hypercarbia and acidosis during periods of carb on dioxide pneumoperitoneum. However, preoperative pulmonary function measures of decreased flow, limited capacity, and compromised diffusio n do correspond to the development of intraoperative acidosis. Preoper ative evaluation with pulmonary function tests demonstrating forced ex piratory volumes less than 70% of predicted values and diffusion defec ts less than 80% of predicted values can identify those patients who a re at risk of developing hypercarbia and acidosis.