Regional anaesthesia and cough effectiveness : a study in patients undergoing Caesarean section

We report the results of a study of the effects of spinal and epidural anaesthesia for Caesarean section on commonly used indicators of a patient's ability to cough effectively. Both spinal and epidural anaesthesia, after the achievement of a block adequate for surgery, were associated with statistically significant decreases (p less than 0.05) in all the respiratory variables recorded: forced vital capacity, forced expiratory volume in one second, peak expiratory flow rate and maximum expiratory pressure. We conclude that although the observed changes are unlikely to impair the normal patient's ability to cough effectively in these circumstances, there may be clinically significant impairment in the presence of an inadvertently high block or in a patient with pre-existing pulmonary disease.