BACKGROUND AND OBJECTIVES: Notwithstanding pleural block having become almost an analgesic panacea, contradictory results have been published. This study aimed at observing analgesic and spirometric behavior of pulmonary function in the immediate postoperative period of 21 patients submitted to urgency median laparotomies under bilateral pleural block. METHODS: Bilateral pleural block was induced in the supine position with 20 mL of 0.375% bupivacaine with 1:400,000 epinephrine administered via catheter in each hemithorax during the immediate postoperative period. Randomized bupivacaine and saline were administered by residents or nurses blind to syringes content, and their analgesic outcomes were evaluated according to Prince Henry's pain score by comparing pre and post bilateral pleural block values. As a function of postoperative pain, spirometric tests of pulmonary function were also applied via a portable spirometer. RESULTS: All bupivacaine patients referred postoperative analgesia with mean duration of 247.75 ± 75 minutes although there has been mild residual pain in the suprapubic region of five patients (8%) and in the xiphoid apophysis in two patients (3.2%). No analgesic effect was obtained with saline. Pulmonary function evaluated pre and post-blockade were improved with bupivacaine in FVC (p < 0.0367) and FEV1 (p < 0.0051). No improvement was seen in EFP (p < 0.059) and FEV1/FVC ratio (p < 0.1263). CONCLUSIONS: In our study, postoperative pain control with bilateral pleural block after urgency median laparotomies was null with saline. With bupivacaine, however, analgesia was not considered fully effective in all patients during movements on bed and deep breathing. Pleural block does not seem to have the same analgesic outcome for all patients.