Magnesium concentrations in blood and cerebrospinal fluid during delirium tremens

Unpeeling the Evidence for the Banana Bag: Evidence-Based Recommendations for the Management of Alcohol-Associated Vitamin and Electrolyte Deficiencies in the ICU

OBJECTIVE

Patients with a chronic alcohol use disorder presenting to the ICU may be deficient in important vitamins and electrolytes and are often prescribed a "banana bag" as a reflexive standard of therapy. The difficulty of diagnosing Wernicke's encephalopathy in the critical care setting is reviewed. Furthermore, whether the contents and doses of micronutrients and electrolytes in standard banana bags meet the needs of critically ill patients with an alcohol use disorder is assessed based on available evidence.

DATA SOURCE

MEDLINE/PubMed (1966 to June 2015) database search, the Cochrane Database of Systematic Reviews, and manual selection of bibliographies from selected articles.

STUDY SELECTION AND DATA EXTRACTION

Articles relevant to Wernicke's encephalopathy, vitamin and electrolyte deficiencies in patients with alcohol use disorders, and alcoholic ketoacidosis were selected. Articles were narratively synthesized for this review.

DATA SYNTHESIS

Of these deficiencies, thiamine is the most important for the practicing clinician to assess and prescribe replacement in a timely manner. Based on a pharmacokinetic assessment of thiamine, the banana bag approach likely fails to optimize delivery of thiamine to the central nervous system. Folic acid and magnesium may also merit supplementation although the available data do not allow for as strong a recommendation as for prescribing thiamine in this setting. There is no available evidence supporting the prescription of a multivitamin.

CONCLUSIONS

Based on the published literature, for patients with a chronic alcohol use disorder admitted to the ICU with symptoms that may mimic or mask Wernicke's encephalopathy, we suggest abandoning the banana bag and utilizing the following formula for routine supplementation during the first day of admission: 200-500 mg IV thiamine every 8 hours, 64 mg/kg magnesium sulfate (approximately 4-5 g for most adult patients), and 400-1,000 μg IV folate. If alcoholic ketoacidosis is suspected, dextrose-containing fluids are recommended over normal saline.

Substance abuse and withdrawal in the intensive care unit. Contemporary issues

Because 36% of intentional injury victims are drug dependent, the association between drug abuse and violence, especially in urban settings, is high. Withdrawal syndromes in ICU patients confuse their clinical management, may be extremely difficult to diagnose, are often lethal, need to be suspected, and should be prophylaxed against; therefore, all ICU patients should be considered to be at high risk for drug or alcohol dependence, should be tested for evidence of such drugs, and should be interviewed (together with their family members) for the presence of drug dependence traits. Appropriate patients should be referred for formal evaluation and treatment. Withdrawal syndromes must be promptly recognized, differentiated from traumatic or metabolic deterioration, and immediately treated. As patients are unique, so is their drug dependence. Individualized withdrawal therapy, not a "one method fits all" approach, works best. The mainstay of most withdrawal therapy is supportive care and benzodiazepine therapy. Also, considering the high rate of multiple intoxicants present in trauma patients, withdrawal can occur from multiple agents in a single patient, further compounding these difficulties. Withdrawal from unusual substances, such as GHB, or from therapeutic interventions (e.g., prolonged opioid or benzodiazepine administration) also must be considered.

Thiamine pyrophosphate effect and erythrocyte transketolase activity during severe alcohol withdrawal syndrome

The thiamine pyrophosphate (TPP) effect and erythrocyte transketolase activity (ETKA) in a group of 28 patients admitted to a psychiatric emergency ward because of severe alcohol withdrawal syndrome were compared with the TPP effect and ETKA in a control group of 20 healthy nonalcoholic volunteers. The patients were treated with 300 mg thiamine 3 times daily as intramuscular injections, and the TPP effect and ETKA were measured after 1 and 4 days of treatment. No difference was found between the patient group and the control group with regard to the TPP effect and ETKA and no decline in the TPP effect was found in the patient group after 4 days of intensive treatment with thiamine. ETKA increased with intensive thiamine treatment, which suggests that ETKA is a sensitive indicator of thiamine deficiency. Serum magnesium, which is a cofactor for thiamine pyrophosphate, decreased significantly with the disappearance of alcohol from the blood in patients with high initial blood alcohol levels, but this shift did not interfere with biological thiamine activity.

Controversies over the use of magnesium sulfate in delirium tremens

OBJECTIVE

To critically address the controversy of using parenteral magnesium sulfate in delirium tremens (DT).

DATA SOURCES

English-language journal articles published between 1954 and 1987.

STUDY SELECTION

All literature available, mostly case reports, that either support or discourage magnesium sulfate administration to patients with DT.

DATA EXTRACTION

Pertinent information (as judged by the authors) was summarized and interpreted.

DATA SYNTHESIS

DT has long been associated with magnesium deficiency because many alcoholic patients with DT have low serum magnesium concentrations. Recent literature, however, suggests that hypomagnesemia is not noted universally in this patient population and that patients' serum magnesium concentrations may return to normal without exogenous magnesium administration. Thus, there is most likely not a specific causal relationship of hypomagnesemia in DT.

CONCLUSIONS

Routine administration of parenteral magnesium sulfate in patients with DT is not recommended.

Delirium tremens and related clinical states: changes in calcium and inorganic phosphate concentrations in plasma and cerebrospinal fluid

Calcium and inorganic phosphate were measured in blood and cerebrospinal fluid (CSF) in 11 patients during impending delirium tremens (grade 2) and in nine patients with fully developed delirium tremens (grade 3). The initial sampling of blood and CSF was performed at admission before treatment was initiated. The blood sampling was repeated daily until recovery and at this time a second lumbar puncture was also performed. In grade 3 patients the plasma calcium concentration showed a transient increase after admission; in grade 2 patients the plasma calcium concentration was also somewhat elevated. The changes in plasma calcium concentration after admission correlated significantly with the changes in blood alcohol concentration. In grade 3 patients the CSF calcium concentration decreased between admission and recovery, this possibly relating to an increased cerebral binding capacity in the post intoxication period. No statistically significant changes were seen in either of the diagnostic categories as far as plasma inorganic phosphate concentrations are concerned. CSF inorganic phosphate concentration decreased in a fashion correlated with CSF alcohol concentration and, finally, CSF inorganic phosphate at admission was somewhat lower in grade 3 patients as compared to grade 2, this possibly reflecting a more severe disturbance of cerebral metabolism in grade 3 patients. Essentially, grade 3 patients had lower CSF concentrations of both calcium and inorganic phosphate as compared to grade 2 patients and thus there may exist real differences in the metabolism of these two ions when a severe withdrawal reaction (grade 2) is compared to fully developed delirium tremens (grade 3).

The effects of alcohol on blood pressure and electrolytes

The interaction between alcohol abuse, changes in blood pressure, and electrolyte abnormalities is complex. Some effects of alcohol are seen only with acute ingestion, some during withdrawal, and some only in chronic drinkers. Careful attention to the interactions between the metabolism of various electrolytes can prevent unnecessary morbidity and mortality in alcoholic patients.

Haematological changes and state of hydration during delirium tremens and related clinical states

In order to obtain some information about the state of hydration and possible haematological changes in patients with delirium tremens (grade 3) and related clinical states (grade 2) various clinico-chemical variables were measured at the time of admission and repeatedly until clinical recovery from the psychotic state. In grade 3 patients plasma protein concentration, blood haemoglobin concentration, blood haematocrit and erythrocyte count decreased between admission and recovery probably reflecting a slight haemodilution. The changes were all within the normal range for the variables and there was thus no indication of hypo- or hypervolemia. Delirium tremens patients without concomitant somatic diseases should not be routinely treated with intravenous fluid therapy. In grade 2 patients no statistically significant changes occurred in the above mentioned variables. In the grade 3 patients there was a dramatic (100%) increase in plasma iron concentration between admission and the subsequent morning and this was probably related to the elimination of ethanol from the body. In grade 2 patients, where the initial blood alcohol concentration was lower than in grade 3 patients, no change in plasma iron concentration occurred. A statistically significant increase in reticulocyte count between admission and recovery in both grade 3 and grade 2 patients probably reflected the recovery of haemopoietic tissue from the insult of the preceding ethanol intoxication. The same may be true for the prevailing anisocytosis, whereas the trend towards leucocytosis may be due to unspecific stress during the ethanol withdrawal reaction. The rapid changes in some of the clinico-chemical variables stress the importance of initiating investigational procedures immediately at the hour of admission.

Effects of acute ethanol intoxication, chronic ethanol intoxication, and ethanol withdrawal on magnesium and calcium metabolism in the rat

Effects of ethanol intoxication and withdrawal on magnesium and calcium metabolism were studied in rats. During acute ethanol intoxication, plasma [Mg2+] was increased and plasma [Ca2+] decreased. During chronic intoxication, plasma [Mg2+] was normalized whereas plasma [Ca2+] was persistently subnormal. Ethanol withdrawal was followed by a decrease in plasma [Mg2+] and a normalization of plasma [Ca2+]. These various changes are probably related to changes in systemic pH and to the biochemical effects of ethanol and ethanol withdrawal on intermediary metabolism. Cerebrospinal fluid [Mg2+] was unchanged during intoxication and withdrawal and it was concluded that no etiological role can presently be ascribed to the magnesium ion as far as cerebral signs of ethanol intoxication and withdrawal in the rat are concerned. No consistent changes in erythrocyte [Mg2+] were encountered during ethanol intoxication and withdrawal in rats.