Impairment of cognitive and psychomotor function by ethanol in social drinkers

Ethanol is known to impair cognitive and psychomotor function in high doses. We studied the impairment of cognitive, psychomotor and behavioral responses in controlled environment in a group of healthy young social drinkers at below and above legal limit for presumption of intoxication (100 mg/dl). Attention, concentration, auditory-verbal memory and memory for visuospatial information were significantly impaired at both levels. Motor speed was impaired only at higher levels though fine coordination was impaired at both doses. Females showed more impairment on visual as well as auditory-verbal memory functions. With low doses, choice reaction time improved with the nonpreferred hand.

Comparative single-dose pharmacokinetics of amantadine hydrochloride and rimantadine hydrochloride in young and elderly adults

The single-dose pharmacokinetics of amantadine hydrochloride and rimantadine hydrochloride were compared in a randomized, two-period, crossover study involving six young (less than or equal to 35 years) and six elderly (less than or equal to 60 years) adults. Subjects ingested single 200-mg oral doses after an overnight fast, and serial plasma (0 to 96 h), nasal mucus (0 to 8 h), and urine (0 to 24 h) samples were collected for assay of drug concentration by electron capture gas chromatography. For both groups combined, rimantadine differed significantly from amantadine in peak plasma concentration (mean +/- standard deviation, 0.25 +/- 0.06 versus 0.65 +/- 0.22 micrograms/ml), plasma elimination half-life (36.5 +/- 15 versus 16.7 +/- 7.7 h), and percentage of administered dose excreted unchanged in urine (0.6 +/- 0.8 versus 45.7 +/- 15.7%). No significant age-related differences were noted for rimantadine. Urinary excretion (0 to 24 h) of rimantadine and its hydroxylated metabolites averaged 19% of the administered dose. The maximum nasal mucus drug concentration was similar for both drugs (0.42 +/- 0.25 versus 0.45 +/- 0.32 micrograms/g), and the ratio of maximum nasal mucus to plasma concentration was over twofold higher after rimantadine than after amantadine. These findings may in part explain the clinical effectiveness of rimantadine in influenza A virus infections at dosages that have lower toxicity than those of amantadine.

Poisonings

While the three demonstration programs failed to document a major impact on prevention of poisoning, they do provide a rationale for selected strategies that may have wide application. Future efforts and successes in poison prevention will involve both the primary care physician and the poison center, using primary and passive interventions. The primary physician can be a source of information and counseling, while the poison center, having succeeded in secondary prevention, can expand its role into primary prevention.

Submersion injury. Epidemiology, prevention, and management

The epidemiology of injuries resulting from submersion in water and their prevention are reviewed and the management of submersion injury is detailed.

Sulindac hepatotoxicity: a case report and review

A 44 year old female, previously on propranolol, phenytoin and phenobarbital, developed hepatotoxicity while on sulindac and acetaminophen containing analgesic. A limited review of hepatotoxicity and drug interactions of sulindac is presented. The possible mechanism of hepatotoxicity and its treatment is suggested.

Pharmacokinetics of multiple-dose cefoperazone in hemodialysis patients

We studied the pharmacokinetics of cefoperazone 2 g i.v. every 12 h for 7 days in 12 patients on hemodialysis with normal hepatic function. The half-life of indocyanine green was determined in each patient via ear oximetry. Serum levels of cefoperazone during dialysis were well described by a two-compartment multidose infusion model. From this model we determined the steady state volume of distribution (Vdss), elimination phase half-life during dialysis T1/2D) and off hemodialysis (T1/2), and the corresponding elimination rate constants (KeD and Ke). Multiple correlations between pharmacokinetic parameters, liver function, and physical characteristics of the patients were evaluated. The T1/2 of cefoperazone was 2.9 h off compared to 2.3 h during hemodialysis. The corresponding elimination rate constants were Ke = 0.45/h versus KeD = 0.80/h. Cefoperazone clearances were 78 ml/min off dialysis compared to 140 ml/min during hemodialysis. Vdss was 0.20 liters/kg. The indocyanine green half-life ranged from 1.8 to 4.6 min with a mean of 2.7 min. The ages of the patients correlated with the beta phase half-life (r = 0.68, p = 0.015). We found no significant correlations among the other parameters including hepatic enzymes and indocyanine green half-life. Thus, hemodialysis approximately doubles the elimination rate constant (clearance), but, assuming drug redistribution kinetics remain unchanged, only shortens half-life by about 20%. Scheduling of a 12-hour dosing regimen to coincide with the end of hemodialysis should obviate any need for alteration of dose. Cefoperazone is thus unique among cephalosporins, since the half-life does not change appreciably with end-stage renal disease or dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

The deterrent effect of poison-warning stickers

We examined the effect of poison-warning stickers on toddler behavior before and after an education program. Twenty children aged 12 to 30 months were randomly assigned to an experimental or control group. We observed the children for two five-minute sessions in a room containing ten pairs of containers, half of which were labeled with Mr Yuk stickers. Each child was allowed to play freely on the floor, and we recorded the manipulations of the labeled and unlabeled containers. During session 1, neither group showed a statistical preference for labeled or unlabeled containers. During session 2, control subjects again did not show a preference for labeled or unlabeled containers. We found that children in the experimental group preferred to touch labeled containers after undergoing education. Our findings suggest that toddlers may not be deterred from manipulating containers that are labeled with poison-warning stickers.

A user-oriented information system for emergency medicine

A user-oriented Emergency Medical Services Information System ( EMSIS ) has been developed in our medical center that can readily be established by any interested medical center. This minicomputer based system provides online registration of poison center calls, access to the Poisindex (C) data base, concise patient information sheets, access to EMS treatment protocols, assistance in the differential diagnosis of acute poisoning, dosage recommendations for drugs with a narrow therapeutic margin, and kinetic analysis of drug overdoses. Video terminals access EMSIS in the Emergency Department, pharmacy, outpatient medicine clinic, pediatric clinic, medicine wards, poison control center, and biomedical engineering. A PDP 11/70 with 256 Kb core and 48 ports running under RSTS /E V7 .0 supports an average of 20 simultaneous users.

Generalized convulsions as the presenting sign of amoxapine intoxication

Two infants presented for medical evaluation with sudden onset of seizures or coma, without obvious cause. Suspicious circumstances led to toxicological screening analysis. Amoxapine, a recently released antidepressant, was found in the gastric contents of both children an undetermined time after the putative ingestion, but elevated serum concentrations were noted only in one. The pharmacokinetics are described. There were no obvious cardiotoxic or anticholinergic effects in these infants. Thus, they, like older children and adults, manifest mainly central nervous system toxicity rather than the cardiotoxicity and anticholinergic effects of overdose seen with tricyclic antidepressants.

Effect of activated charcoal in 70% sorbitol in healthy individuals

Activated charcoal in 70% sorbitol enjoys wide use in the management of acute poisonings but the effects of the activated charcoal-sorbitol mixture in healthy individuals have not been characterized. We were concerned about the possibility of sorbitol causing changes in the routinely monitored serum chemistry and hematological parameters, either directly due to the absorbed polyol or due to the diarrhea induced by it, thus complicating the diagnosis and management in an overdose setting. We assessed the action of a single dose of 30g of activated charcoal in 150 ml of 70% sorbitol and its effects on serum osmolality, electrolytes, metabolic profile (SMAC), magnesium, hepatic enzymes, and complete blood count in healthy adult individuals. The only significant change in the laboratory parameters tested was the consistent rise in serum sodium and phosphorus concentrations four hours after drinking the charcoal-sorbitol mixture. However, a similarly consistent rise in the concentrations at the same hours on another day without ingestion of the charcoal-sorbitol mixture suggested the rise was due to circadian rhythm or other factors unrelated to the cathartic. The lack of effect on routinely monitored laboratory parameters, relative palatability and the rapid onset (40-225 minutes), and long duration (7 to 127 hours) of purgation, make charcoal-sorbitol an attractive combination for use as a gastrointestinal decontaminant. Possible effects of multiple dose regimens and the effects in pediatric and geriatric populations need further study.

Yellow rain: chemical warfare in Southeast Asia and Afghanistan

Circumstantial and laboratory evidence has accumulated supporting the use in Southeast Asia and Afghanistan of Russian-made lethal chemical agents. In this paper we will attempt to answer the question, "What is Yellow Rain?", summarize some of the massive data on microtoxins and mycotoxicoses, discuss the toxicology of the trichothecenes, give a brief historical perspective on chemical warfare, and touch on some of the political implications of these developments. The ubiquitous and insidious mycotoxins have been more or less causally linked to several human diseases, from ergotism to Reye's syndrome, as well as enormous livestock morbidity and mortality. We raise the concern that the Yellow Rain "experiments" pose the threat of massive use of chemical/biological warfare. The importance of an informed, vocal medical constituency cannot be overestimated.

Pharmacokinetics of aztreonam in patients with various degrees of renal dysfunction

We have studied the pharmacokinetics of 1-g intravenous doses of aztreonam in four groups of six volunteers each, distinguished by their creatinine clearances (greater than 80, 30 to 80, 10 to 29, and less than 10 ml/min). Subjects received 1 g of aztreonam intravenously without any complications. Aztreonam serum and urine levels were measured by microbiological methods and by high-pressure liquid chromatography, and unbound serum aztreonam was determined by ultrafiltration. Serum levels were well described by a two-compartment infusion model. From this model we determined steady-state volume of distribution, alpha distribution phase half-life, beta elimination phase half-life, and total clearance of aztreonam. The mean of beta elimination phase half-life ranged from 2 h in normal subjects to 6 h in anephric patients. The total clearance of aztreonam correlated closely with corrected creatinine clearance calculated from serum creatinine, age, and sex (r = 0.97, P less than 0.001) and ranged from a mean value of 107 ml/min in normal subjects to 29 ml/min in functionally anephric patients. Some 75% of aztreonam excretion was renal. Urinary recovery of aztreonam ranged from 58% of the administered dose in normal subjects to 1.4% in uremic patients. Free aztreonam in serum correlated inversely with creatinine clearance (P less than 0.001). A nomogram was developed as a guide for adjustment of aztreonam dosage according to renal function.

Differences in side effects of amantadine hydrochloride and rimantadine hydrochloride relate to differences in pharmacokinetics

In a double-blind, placebo-controlled study, the comparative toxicities and blood concentrations of amantadine hydrochloride and rimantadine hydrochloride were determined. Healthy, working adults ingested either 200 (n = 52) or 300 mg (n = 196) per day in divided doses for 4.5 days. Mean plasma drug concentrations at 4 h after the first dose were lower in rimantadine recipients given 100- (140 versus 300 ng/ml for rimantadine and amantadine, respectively; P less than 10(-5)) or 200-mg doses (310 versus 633 ng/ml; P less than 10(-5)). The plasma drug concentrations after the first dose correlated significantly with total symptom sources for both amantadine and rimantadine, but the plasma levels of toxic and nontoxic subjects overlapped extensively. At 300-mg/day dosage amantadine was associated more often with adverse central nervous system symptoms (33% of amantadine versus 9% of rimantadine recipients; P less than 0.001) and sleep disturbance (39 versus 13%; P less than 0.001), but not gastrointestinal symptoms (19.5 versus 16.0%). However, no differences between the drugs were noted in symptom frequency or scores in volunteers with similar plasma concentrations. Amantadine and rimantadine differ in their pharmacokinetics but not in their potential for side effects at comparable plasma concentrations.

Strychnine poisoning. Recovery from profound lactic acidosis, hyperthermia, and rhabdomyolysis

Strychnine poisoning results in a predictable and treatable sequence of events involving blockade of the inhibitory neurotransmitter, extensor muscle spasms, seizures, and respiratory paralysis. These spasms may lead to hyperthermia, profound lactic acidosis, and rhabdomyolysis. Acidosis is primarily attributable to lactate, as indicated by the correlation between arterial pH and log of lactic acid concentration (r = -0.878). Interruption of the strychnine blockade is the primary therapy for strychnine poisoning. Phenobarbital in moderate doses should be the first intervention and anesthetic doses should be used if necessary. Suppression of convulsions will permit successful management of the complications of strychnine poisoning. Our patient survived, even though at one point he had a pH of 6.55, a lactate level of 32 mM/liter, a temperature of 43 degrees C, and rhabdomyolysis with an increased creatine phosphokinase level of 359,000 mU/ml (5,983 mumol/s/liter).

Comparison of alphabetic and phonetic retrieval of online drug information

Alphabetic, phonetic, and combined alphabetic and phonetic methods of retrieving online drug information were compared. Twenty-four volunteers participated in the study representing four user groups: physicians, nurses, pharmacists, and nonhealth-care hospital staff. Each subject performed 150 searches, 50 by each retrieval method. Using the alphabetic method, drug information was retrievable only if the drug name was spelled correctly. Using the phonetic method, searches were conducted based on the phonetic spelling of requests (e.g., "symetadine" for cimetidine). The combined method used a phonetic search only after an initial alphabetic search was unsuccessful. The elapsed time between the first entry and an indication that the information had been found or could not be found was determined, and the number of drug names not found and the number of excess tries were counted. There were no significant differences in elapsed time among the three methods. Pharmacists had the shortest mean elapsed time and physicians the longest. The average number of excess tries using the phonetic system was a third of the number required using the alphabetic method. The number of drugs not found showed only slight differences among the three methods. The subjects found the desired information on the first try 67% of the time with the alphabetic method, 66% with the combined method, and 90% with the phonetic method. The phonetic method had an average of 75 matches versus 20 for the alphabetic and combined methods. These results support use of a combined alphabetic and phonetic system for retrieving drug information.

Reduction in caffeine toxicity by acetaminophen

A patient who allegedly consumed 100 tablets of an over-the-counter analgesic containing sodium acetylsalicylate, caffeine, and acetaminophen displayed no significant CNS stimulation despite the presence of 175 micrograms of caffeine per mL of serum. Because salicylates have been reported to augment the stimulatory effects of caffeine on the CNS, attention was focused on the possibility that the presence of acetaminophen (52 micrograms/mL) reduced the CNS toxicity of caffeine. Studies in DBA/2J mice showed that: 1) pretreatment with acetaminophen (100 mg/kg) increased the interval between the administration of caffeine (300 to 450 mg/kg IP) and the onset of fatal convulsions by a factor of about two; and 2) pretreatment with acetaminophen (75 mg/kg) reduced the incidence of audiogenic seizures produced in the presence of caffeine (12.5 to 75 mg/kg IP). The frequency of sound-induced seizures after 12.5 or 25 mg/kg caffeine was reduced from 50 to 5% by acetaminophen. In the absence of caffeine, acetaminophen (up to 300 mg/kg) did not modify the seizures induced by maximal electroshock and did not alter the convulsant dose of pentylenetetrezol in mice (tests performed by the Anticonvulsant Screening Project of NINCDS). Acetaminophen (up to 150 micrograms/mL) did not retard the incorporation of radioactive adenosine into ATP in slices of rat cerebral cortex. Thus the mechanism by which acetaminophen antagonizes the actions of caffeine in the CNS remains unknown.

Computer-aided emergency telecommunications for the deaf

Computer-aided telecommunications provide deaf teletypewriter users with 24-hour toll-free access to emergency services. An interface and software link the deaf caller's teletypewriter (TDD) with a microprocessor by reducing and inverting voltage levels between the two devices. This system facilitates rapid transmission of linguistically controlled triage questions to meet the communication needs of deaf patients.