Effectiveness of Oral Lactulose Versus Lactulose Enema in Hepatic Encephalopathy

Overview

Patients with chronic liver disease due to hepatitis B or C viruses, Non-alcoholic fatty liver disease, autoimmune hepatitis, wilson disease, cryptogenic hepatitis etc are prone to develop complications. Hepatic encephalopathy is one of such complications. It is graded into four types depending on severity of clinical features, which range through altered sleep pattern to coma. The current study aims to compare the effectiveness of lactulose enema with oral lactulose in time to recovery from higher grade of encephalopathy to lower grade of encephalopathy.

Hepatic encephalopathy (HE) is defined as neuropsychiatric disorder due to liver failure. It is characterized by mild cognitive impairment, stupor and coma. The most common reasons for pathogenesis include the role of neurotoxins, impaired neurotransmission due to metabolic changes in liver failure, changes in brain energy metabolism, systemic inflammatory response and alterations of the blood brain barrier. Neurotoxin ammonia is related to precipitating HE, for which the gastrointestinal tract is the primary source. Colonic bacteria catabolise the nitrogenous sources into ammonia. Lactulose is the initial treatment for HE. It produces diarrhea by osmosis and reduces pH of colonic contents, which leads to reduced absorption of ammonia by converting it to ammonium ion (NH4). Understandingly, it does not cure the underlying liver disease however, it does prevent deterioration of the mental status in HE. Initial oral dose of lactulose is 30 ml once a day or twice daily. For retention enema the dose is 300 ml lactulose plus 700 ml water, administered every 4 hours. It can be increased as tolerated. At least, 2-4 loose stools per day should be passed by the patient. Lactulose is also effective as primary prophylaxis against the development of HE. Constipation is one very common precipitating factor for hepatic encephalopathy which is routinely managed with oral lactulose or kleen enema (21.4g (18.1% w/v) Sodium Dihydrogen Phosphate Dihydrate and 9.4g (8.0% w/v) Disodium Phosphate Dodecahydrate). Lactulose enema is also given to patients in hepatic encephalopathy either alone or in combination with oral lactulose. However it is not clear whether there is any difference in the efficacy of oral or enema lactulose in patients with hepatic encephalopathy in terms of improvement of encephalopathy grade and time to improvement. This study aims to determine the efficacy of oral versus enema lactulose in the achievement of these goals.