Table 3

An overview of the systemic effects of status epilepticus

System

Effects


Lungs

Due to both metabolic and respiratory acidosis, the pH of arterial blood gases (ABG) is often found to be below normal in SE. Aminoff and Simon found that 59/80 (84%) of the patients with useable ABG information had pHs below 7.35 [43]. They suggest that the aberrations in pH may not be of clinical significance or of prognostic value.

In animal studies, pulmonary vascular pressure has been found to be elevated in SE [44] and may contribute to pulmonary edema [45].

Heart

The sympathetic overdrive can cause tachycardia. In a study by Boggs, potentially fatal arrhythmias were reported in 58% of the patients [46].

In a recent study, Boggs et al completed hemodynamic monitoring in SE patients 24 hours prior to their death, and found that there were two distinct groups with disparate cardiac manifestations [47]. In the group with a lower proportion of previously discovered atherosclerotic disease (ASHD), there was acute cardiac decline without a significant drop in mean arterial pressure (MAP) or heart rate (HR). The second group, 90% of whom had a history of multiple risk factors for ASHD, showed a gradual decrease in MAP and HR prior to death.

Muscle

As a result of continued seizure activity, conversion to anaerobic metabolism contributes to lactic acidosis [3].

Blood chemistries

De-margination of neutrophils occurs with the stress of seizing. In patients without underlying infection, elevated white blood cell counts (above the upper laboratory limit) were present in as many as 63% in one study [43].

Vital signs

Blood pressure

The initial phase of SE results in an increased systemic blood pressure with an increase in peripheral vascular resistance [43]. As the status becomes prolonged, the blood pressure will normalize or even begin to fall with resultant hypotension.

Temperature

As the seizure progresses, the body's core temperature elevates. Aminoff and Simon looked at the temperature of 90 patients in SE. Of these, only 8 had temperatures below 98°F, only 3 had fever secondary to known infection, and over 40 had temperatures above 100.5°F, (with two of the temperatures up to 107°F) [43].

Respiratory rate

The patient in SE often has a transient change in respiratory rate and tidal volume [22].


Bassin et al. Critical Care 2002 6:137-142   doi:10.1186/cc1472