Seizures And Hepatic Disease

Hepatic failure can either complicate a critical illness or be the main reason for ICU admission. Seizures can arise as a result of increased ammonia levels, abnormal glutamine metabolism, cerebral ischaemia or oedema, accumulation of toxins or associated biochemical abnormalities such as hypoglycaemia, hyponatraemia and hypomagnesaemia 19, 20, 21 . The true incidence of seizures in hepatic encephalopathy is unknown. It has been reported as 2-33 22 . The most characteristic EEG changes are...

Differential Diagnosis

Seizures often mimic a number of other common conditions. These conditions include syncope, TIA, transient global amnesia (TGA) and vertigo. Several diagnostic tests may be useful in differentiating seizures from other conditions. Yet, the most important aspect of evaluation is considering seizures in the differential diagnosis and obtaining a clear, detailed history. Diagnostic tests help to narrow the differential diagnosis. The gold standard for diagnosis is a witnessed description of the...

Zonisamide

Zonisamide is felt to be broad spectrum 85, 86 . Unfortunately, trials in generalized seizure syndromes have not been performed to confirm this clinical impression. The only randomized controlled trials were performed in adults with partial seizures 46 . Randomized trials in patients with newly diagnosed epilepsy have also not been done. Case series and open studies support a role for zonisamide in the treatment of syndromes associated with myoclonus, including juvenile myoclonic epilepsy and...

Pregabalin

Pregabalin has a similar efficacy profile to gabapentin, that is to say its use is restricted to partial seizures 91 . No formal monotherapy studies have been completed, in either newly diagnosed or refractory patients. An advantage of pregabalin when compared to gabapentin, is that it is highly bioavailable, and does not require active dose-dependent transport in the GI tract 92 . Pregabalin is better tolerated when titrated. A recent study indicated that starting at the highest dose of 600...

Seizures And Renal Disease

Seizures in renal disease are secondary to one or more factors, including hyponatraemia, hypocalcaemia, uraemia itself, hypertensive encephalopathy, medication toxicity or disequilibrium syndrome seen with haemodialysis. In the few studies that looked at occurrence of seizures in patients with renal failure and or on haemodialysis, seizures occurred in 2-10 of patients 30-32 . Seizures associated with kidney transplants will be discussed later. Treatment of these patients may be problematic due...

Renal Disease

Seizures may occur in uraemic encephalopathy, dialysis disequilibrium syndrome and dialysis encephalopathy. In addition, renal insufficiency and dialysis may both have effects on AED pharmacokinetics. Renal impairment can alter the fraction of AED absorbed, volume of distribution, protein binding and renal drug clearance. Renal impairment may alter the gastric pH, cause small intestinal bacterial overgrowth, gastrointestimal tract oedema and impaired gastrointestinal motility 28, 29 . These...

AED DosiNG sCHEDuLEs

Dosing intervals that are inappropriately long can lead to problems with both tolerability, when serum concentrations are too high, and efficacy, when they are too low 71 . This is only a problem for certain drugs, depending on whether the drug truly has a wide therapeutic window. Carbamazepine has a narrow therapeutic window because many people experience toxicity at higher serum concentrations and breakthrough seizures if the concentration is too low. For example, serum concentrations above...