Preoperative pulmonary function evaluation for laparoscopic cholecystectomy
C. M. Wittgen, K. S. Naunheim, C. H. Andrus and D. L. Kaminski
Department of Surgery, St Louis (Mo) University Medical Center.
OBJECTIVE: Hypercarbia with respiratory acidosis is a recognized
complication of laparoscopic cholecystectomy. This study was performed to
identify preoperatively those patients who may develop hypercarbia and
acidosis during the procedure. DESIGN: Retrospective analysis of
preoperative variables. PATIENTS: Thirty-one consecutive patients underwent
laparoscopic cholecystectomy at one institution who were receiving both
preoperative pulmonary function tests and arterial blood gas analysis.
RESULTS: More than 80 demographic, laboratory, and perioperative variables
were entered into a univariate analysis to identify predictors of
intraoperative acidosis (pH, < 7.35). Patient age, duration of the
procedure, and preoperative blood gas values were not predictors of
intraoperative acidosis. Several univariant predictors for patients
experiencing carbon dioxide pneumoperitoneum-induced hypercarbia were
identified; these included an elevated American Society of
Anesthesiologists 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
capacity of the lung for carbon monoxide. CONCLUSIONS: This study suggests
that neither age nor preoperative arterial blood gas values are predictive
of intraoperative hypercarbia and acidosis during periods of carbon dioxide
pneumoperitoneum. However, preoperative pulmonary function measures of
decreased flow, limited capacity, and compromised diffusion do correspond
to the development of intraoperative acidosis. Preoperative evaluation with
pulmonary function tests demonstrating forced expiratory volumes less than
70% of predicted values and diffusion defects less than 80% of predicted
values can identify those patients who are at risk of developing
hypercarbia and acidosis.
