Non-perforation tension pneumoperitoneum resulting from primary non-aerobic bacterial peritonitis in a previously healthy middle-aged man: a case report

BACKGROUND Tension pneumoperitoneum is a rare surgical emergency in which free intraperitoneal gas accumulates under pressure. The known sources of free gas are perforated hollow viscera. We believe this is the first published case of a tension non-perforation pneumoperitoneum secondary to anaerobic gas production. This occurred in a background of primary non-aerobic bacterial peritonitis, which developed in an immunocompetent adult man. CASE PRESENTATION A previously healthy 45-year-old Bulgarian man presented with a 3-week history of abdominal pain. He displayed signs of shock, peritonitis, and abdominal compartment syndrome. A plain abdominal X-ray showed the pathognomonic "saddlebag sign" with his liver displaced downwards and medially. An emergency laparotomy released pressurized gas, accompanied by 3100 mL of foamy pus. A sudden hemodynamic deterioration occurred soon after decompression. The sources of infection and tension pneumoperitoneum were not found. The peritoneal exudate sample did not recover aerobes. A laparostomy was created and three planned re-operations were performed. During the second re-laparotomy we placed an intraperitoneal silo and his abdomen was closed with skin sutures. Definitive fascial closure was achieved through separation of his two rectus muscles from their posterior sheaths. He was discharged in good health on the 25th postoperative day. CONCLUSIONS Our case provides evidence supporting the theory that anaerobic infection may underlie the etiology of tension pneumoperitoneum. Prior to decompressive laparotomy the patient should receive an intravenous volume bolus to compensate for possible hypotension. If laparostomy leads to lateralization of the rectus muscles with a gap of 6 cm or less, the posterior part of the components separation technique is effective in achieving fascial closure. We present an original classification of tension pneumoperitoneum defining it as primary or secondary.