Autonomic Dysreflexia

Acute SCI patients may also experience autonomic dysreflexia, a condition characterized by transient episodes of hypertension and imbalanced reflex sympathetic discharge in response to stimulation below the level of injury. AD is a life threatening condition and if not recognised and timely managed could result in significant complications and even death (Dolinak et al. 2007; Pan et al. 2005; Wan et al. 2014). During AD, systolic BP can reach up to 300 mmHg and is accompanied by symptoms such as headache, slow HR and upper body flushing. This reaction is seen in SCI patients with lesions above level T6, with rare occurrences in injuries below this level (Karlsson 2006; Krassioukov et al. 2003). AD is recognized as a cardiovascular complication more characteristic of subacute or chronic SCI but has been observed in some cases to occur earlier (Krassioukov 2009; Krassioukov et al. 2003; Silver 2000).

AD is well recognized as a complication characteristic of chronic SCI, as it does not occur immediately but can rather take several weeks or even months to develop post injury (Karlsson 2006; Teasell et al. 2000). AD is clinically defined as a systolic blood pressure that rises above baseline by at least 20 mmHg (Krassioukov et al. 2012). To date, AD has also been documented to occur as an acute complication of SCI, although rarely. Only one observational study was found which investigated the incidence of this complication during acute SCI. Krassioukov et al. (2003) retrospectively reviewed the incidence of early episodes of AD within a group of acute SCI patients. In this population, 5.2% of patients developed early episodes of AD, occurring between four and seven days post injury. All individuals with evidence of early AD had complete cervical injuries. A case series by Silver (2000) of four patients with acute cord transections reported the presence of early AD between days seven and 31 after sustaining injury.