RESUMO
STUDY DESIGN: Prospective. OBJECTIVE: To analyze tidal volume (TV), minute volume (VE), respiratory frequency (f), vital capacity (VC), maximal inspiratory (PImax), and expiratory (PEmax) pressures in patients submitted to spinal surgery for tumor or herniated disc by posterior access, and to investigate a possible association of respiratory function with surgery duration, site of surgical access, and diagnosis. SUMMARY OF BACKGROUND DATA: A reduction in pulmonary volumes is usually seen in patients submitted to thoracic or upper abdominal surgery, and recent studies have demonstrated such alterations during the postoperative period in patients submitted to craniotomy. METHODS: A total of 45 patients (mean age, 42 +/- 14 years) were submitted to spinal surgery in an University Hospital, and TV, VC, MV, f, PImax, and PEmax were measured in the preoperative period, and in the first and second postoperative days. RESULTS: Patients submitted to spinal surgery showed a decrease in the first and second postoperative days in VC, respectively (17% and 10%), TV (18% and 13%), PImax (17% and 12%), PEmax (12% and 7%), and an increase in f (18% and 12%) (P < 0.05). Reduction in TV, VC, PImax, and PEmax and the increase in f were associated with surgical time > or =240 minutes, diagnosis of tumor, and cervicothoracic surgical access (P < 0.05). CONCLUSIONS: Alterations in the respiratory function in the postoperative period of elective spinal surgery by posterior access for tumor removal or herniated disc were related to surgical time > or =240 minutes, tumor, or cervicothoracic surgical access.
