Botulinum Toxin in Open Abdomen Closure

According to the definition of the World Society for Emergency Surgery (WSES), an open abdomen is defined as the intentional creation of a laparostomy by non-approximation of the aponeurotic edges of the rectus abdominis muscles in the midline (1). This technique is restricted to very specific situations, usually in the critically ill patient who has undergone damage control surgery for polytrauma, abdominal sepsis or abdominal compartment syndrome. In this context, it may be necessary to keep the abdomen open for four indications that were defined in 2015 by an international consensus of experts:

need for reintervention (second-look) in cases of ischaemia or severe intra-abdominal contamination; inability to close due to visceral oedema; traumatic damage to the abdominal wall; failure of medical treatment in the management of abdominal compartment syndrome (2).

Since its description in 1993 (although open abdomen was used for abdominal compartment syndrome decades earlier), the use of damage control surgery associated with intensive resuscitation has decreased mortality in these patients from 90% to approximately 20-30% today (3).

Despite its benefits for the survival of unstable patients, the creation of an open abdomen creates a non-anatomical situation with significant physiological repercussions: exposure of the abdominal viscera to the environment without barrier mechanisms results in hypothermia, and significant fluid and protein loss, precipitating a catabolic state that feeds back into the multi-organ failure of the critically ill patient. In addition, the open abdomen leads to potentially very serious complications such as the development of an enteroatmospheric fistula, which occurs in up to 15% of these patients (2,4,5).

In order to reduce complications and simplify the management of patients with open abdomen, various temporary closure devices have been developed (5). Among them, current evidence recommends the use of negative pressure devices, generally consisting of: a sheet of non-absorbable plastic material in contact with the viscera that tries to prevent the appearance of adhesions and fistulas and which, by presenting small perforations, allows intra-abdominal fluid to escape, a macroporous material that remains in lateral contact with the fascia and subcutaneous tissue, and a final occlusive cover to which suction is applied to generate the negative pressure. The incorporation of these devices has been shown to reduce the production of proinflammatory cytokines in the peritoneal fluid (6) and the aforementioned guidelines recommend their use in all cases of open abdomen (grade of recommendation B, level of evidence I)(2).