Management of open complicated abdomen
Authors: Strandvik Gustav Frans 
Published: December 2019

Critically-ill patients may have their abdomens opened as a result of primary pathology (damage-control laparotomy in trauma, soiled peritoneum from perforated hollow viscus, necrotizing pancreatitis), or as treatment for abdominal compartment syndrome (defined as new organ dysfunction associated with intra-abdominal hypertension).
The incidence and implications of intra-abdominal hypertension and abdominal compartment syndrome (ACS) in particular, are currently debated.
Intra-abdominal hypertension (IAH) is defined as a sustained intra-abdominal pressure ≥ 12 mmHg. Grading is possible; Grade I = IAP 12 to 15 mmHg, Grade II = IAP 16 to 20 mmHg, Grade III = IAP 21 to 25 mmHg, Grade IV = IAP >25 mmHg. Management principles include reduction of intra-abdominal gas (NGT and flatus) and intra-abdominal fluid (the latter may be interstitial or intra-peritoneal), and ensuring the abdominal wall is as compliant as possible. Definitive management is to open the abdomen however, the benefits and use of the open abdomen (OA) approach are unclear. The rates of OA appear to be reducing worldwide.
The reduction in the incidence of ACS requiring laparostomy may be related to global changes in resuscitation targets, rather than changes in surgical techniques. In particular, the notion of ‘fluid de-resuscitation’ may be implicated in improved outcomes.
The decision to leave the abdomen open after emergent laparotomy seems to be dependent on the surgical specialty of the operating surgeon, and is a common approach applied in victims of blunt abdominal trauma.
Complications of the open abdomen relate mainly to nutritional status and long-term abdominal complications. The most feared abdominal complication relates to the inability to close the abdominal fascia, with associated increases in mortality, fistula formation, and ventral hernias.
Current critical care focus is on the prevention of the open abdomen. For intra-abdominal hypertension and acute compartment syndrome, medical management aimed at reduction of abdominal wall pressure and evacuation of intra-abdominal contents (including fluid) are cornerstone strategies. The use of neuromuscular blocking agents is controversial; short-term benefit may be outweighed by long-term complications.
For the de novo open abdomen, current research suggests a possible role for more aggressive early closure (primary or before day 5, latest day 8). Further research is required to confirm whether primary closure is safe. Temporary closure techniques using a combination of negative abdominal wall pressure in combination with partial mesh reduction seems to be helpful in increasing successful abdominal closure rates.
Aggressive infection control and nutritional support after 72 hours is key. Common to both scenarios is the need for careful, judicious fluid management; organ perfusion must be optimized, but not at the expense of massive bowel and abdominal wall edema. The latter complicates healing and closure.
A final question is whether extubating patients with an open abdomen is safe and feasible. The literature provides a resounding yes to this issue.