James D. Beard

The Effect of Alcohol on Fluid and Electrolyte Metabolism

Since the time that the technique of fermentation was learned by prehistoric man, alcohol has been used primarily for its cerebral manifestations, often with unfortunate physiologic consequences. Undoubtedly, a common clinical observation on which Shakespeare commented in Act II, Scene iii of Macbeth was that the drinking of alcoholic beverages promotes an increased flow of urine. Despite this observation, it is of interest how clinical impressions of heavy drinkers changed drastically throughout the history of medicine. During the eighteenth and nineteenth centuries and until 1938, most persons who ingested large quantities of alcohol were described as being “dropsical” (Coffey, 1966). Indeed, between 1718 and 1751 in London, deaths from “dropsical conditions” reached an unprecedented level. It should be noted that this was a general term used for any abnormal amount of fluid in cellular tissue or body cavity, and most forms were associated with excessive drinking. When the mortality rate fell rapidly, physicians at this time attributed the decline to a marked attenuation of public drunkenness. In addition to general edematous states as a result of alcohol ingestion, cerebral edema has been frequently described (Sutton, 1813; Snowden, 1820; Hayward, 1822). Postmortem investigations of patients who died from delirium tremens revealed markedcongestion and turgidity of cerebral blood vessels, turgidity of dural sinuses, together with an increase in subarachnoid and ventricular quantities of cerebrospinal fluid. When the dura was opened, marked quantities of serous fluid were discharged (Sutton, 1813; Snowden, 1820; Hayward, 1822). Treatment was directed at dehydrating the patient because of the “dropsical conditions,” and such techniques as conservative blood letting, purgation (Sutton, 1813; Hayward, 1822), emetics (Klapp, 1817; Snowden, 1820), and hot tub baths (Hayward, 1822; Wright, 1830) were used. Spinal drainage was often used in an attempt to relieve the cerebral edema (Steinbach, 1915).

An animal model for the measurement of acute tolerance to ethanol

Abstract An apparatus is described for the measurement of acute tolerance to ethanol in small animals. Male, Sprague-Dawley rats were trained on the apparatus to leap to a descending platform to avoid being shocked. After an i.p. injection of 2 g/kg ethanol, the rats were tested repeatedly on the apparatus, and the plasma ethanol concentration was measured after each trial. The results demonstrated that the jumping ability of the rats was significantly more impaired during the ascending portion of the plasma ethanol curve than during the descending portion of the curve. Furthermore, it was demonstrated that the improvement in jumping ability during the descending portion of the curve was not dependent on a lowered plasma ethanol concentration. In a second experiment, the possibility of practice effects was eliminated by measuring the jumping ability and plasma ethanol concentration in one group of rats on the ascending portion of the plasma ethanol curve and in another group on the descending portion of the curve. A significant improvement in jumping ability was again observed during the descending portion of the curve, even though the plasma ethanol concentrations of the two groups were comparable. The development of acute tolerance to ethanol was thus demonstrated in both experiments.

Changes in Cardiovascular Activity as a Function of Alcohol Intake

If one would truly appreciate the classic description of alcohol as “man’s psychological blessing and physiological curse” then much of the scientific mysticism surrounding this drug could be removed. The deleterious effects of alcohol oil the heart and blood vessels have long been recognized, yet recent and current medical literature tends to promote the “discretionary” use of ethanol in the treatment of various cardiovascular disorders such as angina pectoris, hypertensive cardiovascular disease, and obliterative vascular disease.

Acute Withdrawal From Alcohol

Acute alcoholic withdrawal is a common clinical problem, and delirium tremens is its most severe form. Symptoms of withdrawal must be evaluated carefully and treated aggressively. The severity of the withdrawal syndrome cannot always be predicted on the basis of quantity or duration of alcohol ingestion. Sedation must be handled with extreme care, and special attention to fluid and electrolyte balance is of the utmost importance.

Renal response of ethanol-treated dogs to increased filtered loads of sodium, bicarbonate, and chloride.

Twenty, male, mongrel dogs were given either 3 g/kg (33% vv solution) of ethanol or an isovolumetric quantity of water by oral intubation. Sixteen hours later the animals were anesthetized and after a control renal clearance, infused with either a hypertonic sodium chloride or sodium bicarbonate solution for an additional three clearance periods. The rate of infusion of solutions was increased progressively prior to each of the next periods. At each new rate, 45 min was permitted for equilibration before the clearance period. The hypertonic NaCl infusion produced similar increases in GFR, the filtered loads of Na and Cl, and the excretory rates of Na and Cl in both the water and ethanol groups. Although the hypertonic NaHCO3 infusion produced equal increases in GFR and filtered loads of Na and HCO3, there were dissimilar increases in Na and HCO3 excretions. Sodium excretion increased by 17.1 ± 1.1 μeq/min/kg and percentage reabsorption decreased by 3.5 ± 0.3% in the water group while in the ethanol group, UNa · V increased by 10.0 ± 1.4 μeq/min/kg (p < 0.01) and %RNa decreased by 1.9 ± 0.2% (p < 0.01). In the ethanol group, bicarbonate excretion increased by 8.1 ± 1.3 μeq/min/kg and in the water group by 12.3 ± 1.1 μeq/min/kg (p < 0.05). The reduction in %RHCO3 was significantly less in the ethanol group in comparison to the water group (8.1 ± 1.0 vs 12.1 ± 0.8%). Known effectors of sodium bicarbonate reabsorption, i.e., volume status, pCO2, potassium stores, and filtration rate were not different between groups. It is concluded that ethanol pretreatment ameliorated the depressant effect of the NaHCO3 infusion on tubular reabsorption.

The use of plasma and urine osmolality in evaluating the acute phase of alcohol abuse

Increasing emphasis on managing acute alcohol- and drug-induced medical-psychiatric conditions demands that rapid screening diagnostic procedures be available to the physician. Since it obviously is useful to have some idea of the blood alcohol concentration (BAC), the feasibility of using plasma osmolality as a reflection of BAC is discussed. The increment in plasma osmolality caused by a unit increase in plasma alcohol is linear, eg, a rise in plasma osmolality of 21.7 mOsm/kg H2O reflects a 100 mg/100 ml increase in plasma alcohol. Since plasma osmolality can be determined rapidly and easily, it can yield useful information and often preface a more thorough biochemical examination. Furthermore, concomitant measurement of urine osmolality can be an indicator of the state of hydration in the acute alcoholic condition. Obtaining an estimate of BAC (by measuring plasma osmolality) allows the physician to correlate signs and symptoms with BAC and to more skillfully plan the psychopharmacologic approach to the patient.