Tension pneumoperitoneum is rare complication that causes severe changes in respiratory and cardiocirculatory function. We report the case of an 84 year old woman who developed tension pneumoperitoneum soon after cholecystectomy by subcostal laparotomy. Tension pneumoperitoneum presented with barotrauma, bilateral pneumothorax, extensive subcutaneous and pneumomediastinum and was accompanied by severe worsening of hemodynamic variables and gas exchange. After confirming the diagnosis by emergency CT scan, the first therapeutic action was decompression of the peritoneal. This fast, simple maneuver was followed by rapid hemodynamic and respiratory improvement. Tension pneumoperitoneum similar to the case we report has been described as a complication of mechanical ventilation and barotrauma; however, the possibility that the clinical picture might be caused by perforation of a hollow viscera has given rise to a variety of suggested therapeutic alternatives, including exploratory laparotomy, which has sometimes later proven to have been unnecessary. In the light of the case we report and the literature, we suggest a therapeutic sequence starting with emergency abdominal decompression and to fulfill two objectives: a) to remove the threat to life, and b) to limit the practice of emergency exploratory laparotomy to cases in which that technique is truly indicated.