Compartment syndrome

Local and regional venom effects can lead to extensive swelling of an entire limb, especially with bites from certain species of snakes. Such symptoms are observed following bites from numerous crotalid species, many viperid species and some elapid species.

Generally this involves swelling of the skin and subcutaneous tissue that nearly always resolves with conservative treatment(Curry et al. 1985, Garfin 1982, Hardy 1991, Kitchens 1992, pers. comm.). Fasciotomy is only necessary in very rare cases. The indication for fasciotomy must be substantiated by measurement of intra-compartmental pressure. There should be clinical suspicion of compartment syndrome if the affected extremity is extremely painful and muscular weakness is present that can be attributed to the muscle group in the affected compartment. In addition there is dysaesthesia in the distribution area of those nerves whose course includes the affected compartment. But even those signs and symptoms can be present in patients with local evenoming but without substantially increased intracompartmental pressure. A peripheral pulse detected by palpation or Doppler ultrasound does not exclude compartment syndrome (Matsen 1980, Warrell 2023).

The intra-compartmental pressure is measured by inserting a probe (cannula) connected to a measuring device into the relevant compartment. If the absolute pressure is over 45 mmHg in an adult or more than 30 mmHg in a child or the difference between diastolic pressure (or mean arterial) blood pressure and measured intracompartmental pressure of less than or equal to 30 mmHg, sustained for more than 30-60 minutes, there is a high risk of intra-compartmental ischaemic necrosis and fasciotomy might be justified. However, to date there has been no evidence that such a measure is able to limit intra-compartmental damage caused by snakebites (Garfin et al. 1984, Warrell 2023).

If a fasciotomy is carried out, adequate haemostasis must be ensured. The importance of establishing this is due to the fact that most snake venoms that caused marked local and regional envenoming also contain haemostatically active components (Warrell 2023).