The treatment of ethylene glycol poisoning has, until relatively recently, consisted of hemodialysis and the intravenous infusion of sodium bicarbonate and ethanol, the latter serving as a competitive substrate for ADH. However, the use of ethanol in this regimen is problematic. Baud and colleagues, and more recently Brent and colleagues and Jacobsen, have advocated the use of intravenous 4- methylpyrazole (fomepizole), which is a far more effective inhibitor of ADH than is alcohol. They recommend this form of treatment for methanol poisoning as well. Information from the American Academy of Toxicology is cited in a review of the use of fomepizole by Brent, which is recommended to the interested reader. Generally, for either methanol or ethylene glycol, a plasma level of the alcohol above 20 mg/dL, or above 10 mg/dL when combined with an osmolal gap over 10 is considered appropriate to institute the drug. In the case of ethylene glycol, oxaluria and acidosis are additional factors that may precipitate treatment. Dialysis remains an essential therapy if cerebral and renal damage is not too advanced.
Some patients who recover from the acute renal and metabolic effects are left with multiple cranial nerve defects, particularly of the seventh and eighth nerves. The latter abnormalities develop 6 to 18 days after the ingestion of ethylene glycol and have been attributed to the deposition of oxalate crystals along the cisternal portions of the affected nerves (Spillane et al).
The Alcohol Abstinence, or Withdrawal, Syndrome
This is the well-known symptom complex of tremulousness, hallucinations, seizures, confusion, and psychomotor and autonomic overactivity. Although a sustained period of chronic inebriation is the most obvious factor in the causation of these symptoms, they become manifest only after a period of relative or absolute abstinence from alcohol—hence the designation abstinence, or withdrawal, syndrome. Figure 41-1 illustrates this concept. Each of the major manifestations of the withdrawal syndrome may occur in more or less pure form and are so described below, but usually they occur in combination. Major withdrawal symptoms are observed mainly in the binge, or periodic, drinker, although the steady drinker is not immune if for some reason he stops drinking, such as during a hospital admission for surgery or a medical illness. The full syndrome, depicted further on, is called delirium tremens.
The most common single manifestation of the abstinence syndrome is tremulousness, often referred to as “the shakes” or “the jitters,” combined with general irritability and gastrointestinal symptoms, particularly nausea and vomiting. These symptoms first appear after several days of drinking, usually in the morning after a night’s abstinence. The patient “quiets his nerves” with a few drinks and is then able to drink for the rest of the day without undue distress. The symptoms return on successive mornings with increasing severity. The symptoms then become augmented, reaching their peak intensity 24 to 36 h after the complete cessation of drinking. Generalized tremor is the most obvious feature. It is of fast frequency (6 to 8 Hz), slightly irregular, and variable in severity, tending to diminish when the patient is in quiet surroundings and to increase with motor activity or emotional stress. The tremor may be so violent that the patient cannot stand without help, speak clearly, or eat without assistance. Sometimes there is little objective evidence of tremor, and the patient complains only of being “shaky inside.”