Past-thoracotomy spirometric lung function: the effect of analgesia

Background. The effects of postthoracotomy pain management on pulmonary fun ction has been assessed. Methods. All English language publications involving prospective, randomise d, controlled studies of patients undergoing postero-lateral thoracotomy in cisions where perioperative spirometry had been studied were included. The mean postoperative percentage preservation of preoperative lung function wa s recorded or determined for each analgesic regimen. Results. 55 studies were reviewed with a total of 1762 patients. The most e ffective analgesic method in terms of preservation of spirometric function was paravertebral analgesia, patients having approximately 75% of their pre operative values in the first 48 hours after surgery. Most other techniques e.g. intercostal nerve blocks, epidural local anaesthetics or local anaest hetic-opiate combinations produced approximately a 55% preservation by 48 h ours. Interpleural analgesia was the least effective, with a mean of 35% pr eservation by 48 hours, less even than TENS or cryoanalgesia. Conclusions. A thoracotomy potentially produces a marked reduction in posto perative pulmonary function and the choice of pain management has major Imp lications. Attenuation of postthoracotomy pulmonary dysfunction by effectiv e analgesia should be provided for all patients undergoing chest surgery. S imply providing effective analgesia on its own without regard to pulmonary function is inadequate. Spirometric monitoring should be standard in all th oracic units and is essential for objective comparisons of the efficacy of different methods of pain management.