Critical Care Medicine-Neurologic Disorders>>>>>Encephalopathy and Delirium
Question 3#

A 67-year-old man with chronic liver disease was admitted to the ICU with confusion and agitation. Laboratory studies are remarkable for hyperammonemia, serum K of 2.9 mEq/L, elevated urine leukocyte esterase, and large quantities of bacteria in urine.

Which of the following interventions is LEAST likely to result in improvement of this patient’s status?

a. Diuresis with furosemide
b. Antibiotics for urinary tract infection
c. Late-night carbohydrate-rich meal when able to tolerate
d. Lactulose
e. Polyethylene glycol

Correct Answer is A

Comment:

Correct Answer: A

In this patient with baseline hypokalemia, diuresis with furosemide is likely to worsen encephalopathy by further decreasing serum potassium level. Hypokalemia increases production of ammonia in the kidneys and may lead to exacerbation of encephalopathy. The 2014 Practice Guideline by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver suggests a four-pronged approach to management of patients with overt hepatic encephalopathy:

  1. Initiation of care for patients with altered consciousness
  2. Identification and treatment of alternative causes of altered mental status
  3. Identification of precipitating factors and their correction
  4. Commencement of empirical HE treatment

In this patient with altered mental status, elevated urine leukocyte esterase and large quantities of bacteria in urine, treatment of the possible urinary tract infection (Answer B) addresses both the alternative cause of altered mental status (urosepsis) and a potential precipitating factor for hepatic encephalopathy.

Nutritional management of hepatic encephalopathy in patients with cirrhosis is outlined in the 2013 Consensus of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism. When patients with overt hepatic encephalopathy can tolerate oral diet, they should be encouraged to eat small meals throughout the day and a late dinner rich in complex carbohydrates (Answer C) to avoid fasting, which leads to production of glucose from amino acids and accumulation of ammonia. Lactulose (Answer D) is a component of empirical treatment of hepatic encephalopathy. Transformation of lactulose by colonic flora lowers colonic pH which favors transformation of absorbable ammonia to nonabsorbable ammonium and decreases plasma levels of ammonia. Polyethylene glycol (Answer E) may be utilized for treatment of hepatic encephalopathy. The proposed mechanism of effect is excretion of ammonia in stool. One study (Rahimi et al. 2014) suggested that polyethylene glycol may be superior to lactulose in treatment of hepatic encephalopathy.

References:

  1. Vilstrup H, Amodio P, Bajaj J, et al. Hepatic encephalopathy in chronic liver disease: 2014 practice guideline by the american association for the study of liver diseases and the european association for the study of the liver. Hepatology. 2014;60:715-735.
  2. Amodio P, Bemeur C, Butterworth R, et al. The nutritional management of hepatic encephalopathy in patients with cirrhosis: International society for hepatic encephalopathy and nitrogen metabolism consensus. Hepatology. 2013;58:325-336.
  3. Rahimi RS, Singal AG, Cuthbert JA, et al. Lactulose vs polyethylene glycol 3350–electrolyte solution for treatment of overt hepatic encephalopathy: the HELP randomized clinical trial. JAMA Intern Med. 2014;174:1727-1733.