Biomedical subjects

S C Curry

Publications and source records attributed to S C Curry.

At least 37 records · Page 2Linked to original sources

PubMed1997

Affinity-purified, mixed monospecific crotalid antivenom ovine Fab for the treatment of crotalid venom poisoning.

SUBJECT OBJECTIVE: To test the efficacy and safety of a new antivenom, affinity-purified, mixed monospecific crotalid antivenom ovine Fab, in human subjects with minimal or moderate crotalid envenomation. METHODS: We conducted a prospective multicenter clinical trial of 11 patients 10 years or older with progressive manifestations after mild to moderate crotalid snakebite. After giving their consent, subjects received four to eight vials of study drug and were then repeatedly examined over 48 hours and at 7 and 14 days after discharge. Each patient's clinical condition was evaluated serially with the use of a validated severity score, as well as on the basis of the investigator's assessment. RESULTS: In all 11 subjects to the antivenom was judged by the investigator to have had a beneficial response. The severity score for each patient remained the same or decreased over the first 4 hours. However, two subjects demonstrated worsened condition 12 to 15 hours after antivenom administration. In no subject did an allergic reaction develop. CONCLUSION: In this patient group, affinity-purified, mixed monospecific crotalid antivenom ovine Fab was associated with a halt of progressive crotalid venom poisoning. Initial safety data are promising but must be addressed further in subsequent studies.

Adolescent↗

PubMed1997

Poisoning by sodium channel blocking agents.

Poisoning by drugs that block voltage-gated sodium channels produces intraventricular conduction defects, myocardial depression, bradycardia, and ventricular arrhythmias. Human and animal reports suggest that hypertonic sodium bicarbonate may be effective therapy for numerous agents possessing sodium channel blocking properties, including cocaine, quinidine, procainamide, flecainide, mexiletine, bupivacaine, and others.

Action Potentials↗

PubMed1997

Crotalid snake envenomation.

Over 5000 Americans suffer from snake bites annually, and of these, nearly one quarter are from poisonous species. Although these cases are undeniably reported, death appears to occur in only a few cases each year, and often reflects delay in obtaining medical care. Two families of venomous snake indigenous to the United States account for most envenomations: Crotalidae (pit vipers or new world vipers) and Elapidae. This article focuses on the snakes of the Crotalidae family.

Animals↗

PubMed1997

Prevention of fetal and maternal cyanide toxicity from nitroprusside with coinfusion of sodium thiosulfate in gravid ewes.

Coadministration of sodium thiosulfate with sodium nitroprusside (SNP) to children and adults prevents increases in cyanide concentrations during anesthesia or long-term SNP infusions. We wondered whether maternally administered sodium thiosulfate would prevent increases in fetal red cell cyanide concentrations in gravid ewes receiving SNP infusions. Under anesthesia, the fetal head was delivered through a lateral hysterotomy for catheterization of the jugular vein; the fetus was left in utero. Six control ewes near term received SNP at 25 micrograms.kg-1.min-1 for 4 h. Norepinephrine was used to maintain maternal mean arterial pressure at 80% baseline values. Six experimental ewes received the same treatment except that sodium thiosulfate was infused with SNP (1 g sodium thiosulfate per 100 mg SNP). Serial red cell cyanide concentrations in ewes and fetuses were followed. One control fetal death resulted from abruptio placenta, and this ewe and fetus were excluded from analysis. An additional control ewe and fetus died from apparent cyanide poisoning late during the course of the experiment. While control ewes and fetuses suffered progressive increases in red cell cyanide concentrations into the toxic range, experimental ewes and fetuses never developed toxic red cell cyanide levels (ewes P < .003, fetuses P < .004). These data, if applicable to humans, suggest that coadministration of sodium thiosulfate with SNP to pregnant women at doses currently in use for nonpregnant patients will prevent fetal, as well as maternal, cyanide toxicity.

Animals↗

PubMed1996

The effect of hypertonic sodium bicarbonate on QRS duration in rats poisoned with chloroquine.

OBJECTIVE: To determine efficacy of hypertonic sodium bicarbonate in narrowing QRS prolongation produced by chloroquine. DESIGN: Randomized, controlled animal experiment using an accepted rat model of sodium channel blockade. METHODS: Hypotension and widening of QRS complexes (lead II) of the ECG were produced in 16 rats by administration of a total of 87 mg/kg chloroquine intravenously over 20 minutes. Eight rats were treated with 6 mL/kg 1 M sodium bicarbonate intravenously over two minutes beginning ten minutes into the chloroquine infusion. Serial measurements of QRS duration and systolic blood pressure were obtained for 30 minutes. RESULTS: QRS intervals narrowed more rapidly in animals receiving sodium bicarbonate (p = .045), although the difference in mean rate of narrowing between groups was modest at only .23 msec/min. Because of large variances, no statistically significant differences could be demonstrated in systolic blood pressure. CONCLUSIONS: Hypertonic sodium bicarbonate partially reversed sodium channel blockade and resultant QRS interval prolongation produced by chloroquine in rats. These data should be interpreted with caution, given the need to extrapolate to humans and the modest effect of sodium bicarbonate on QRS narrowing.

Amebicides↗

PubMed1996

Pool cue chalk: a source of environmental lead.

Lead compounds are used as coloring agents for numerous products. Two cases of children with elevated blood lead concentrations encountered by the authors suggested that pool cue chalk may serve as a source of environmental lead. The objective of this study was to determine lead content of various brands and colors of pool cue chalk. Atomic absorption analyses were conducted of 23 different types of pool cue chalk for lead content. Three of 23 types of pool cue chalk contained more than 7000 ppm (mg/kg) lead: one manufacturer's green and tangerine chalk and another manufacturer's green chalk. It was concluded that some brands of pool cue chalk contain relatively large amounts of lead and could contribute to childhood lead poisoning.

Arizona↗

PubMed1995

Seizure after isolated fluoxetine overdose.

Previous case reports of seizures following fluoxetine overdose have not adequately ruled out ingestion of other substances and have lacked documentation of increased serum drug levels. We present a case of seizure following fluoxetine overdose in a previously well patient with a clear history of sole ingestion. We ruled out the presence of other substances with comprehensive drug screening and documented increased serum levels of fluoxetine and its active metabolite.

Adolescent↗

PubMed1994

Effect of the cyanide antidote hydroxocobalamin on commonly ordered serum chemistry studies.

STUDY HYPOTHESIS: Concentrated aqueous solutions of hydroxocobalamin (OHCob) are given intravenously for the treatment of cyanide poisoning. Because OHCob solutions are intensely red and have peak light absorptions at 352 nm and 525 nm, we investigated whether the presence of OHCob in serum would interfere with various automated, colorimetric chemistry measurements. DESIGN: Selected serum chemistry colorimetric measurements were compared in seven patients, using their own serum as control, with serum containing OHCob at the following concentrations: 100 mg/L, 500 mg/L, and 1,000 mg/L. These concentrations are in the range achieved with therapeutic doses of OHCob when given for cyanide poisoning. MEASUREMENTS AND MAIN RESULTS: Statistically significant alterations in serum values for aspartate aminotransferase, total bilirubin, creatinine, magnesium, and iron were seen in the presence of OHCob. CONCLUSION: The presence of OHCob in serum interferes with several chemistry methodologies, and such interference should be anticipated when this antidote is used.

Adult↗

PubMed1994

Clinical toxicology of ethylene glycol monoalkyl ethers.

The glycol ethers constitute a family of organic solvents commonly found in industrial and household products. Because of their widespread availability and potential for serious toxicity, physicians should be aware of the clinical toxicology of these compounds. Until recently, knowledge of the toxic effects of glycol ethers has been derived from animal studies and a limited number of case reports and small case series. A growing body of data from epidemiological studies, controlled human studies, and studies using human tissue now allows for advancement in the understanding of the acute and chronic toxicity of these compounds. This review summarizes and evaluates human and pertinent animal literature on the clinical toxicology of glycol ethers, with a focus on the commonly encountered monoalkyl ethers of ethylene glycol. Management options for acute poisoning, as well as measures for the control of workplace exposures, are discussed.

Absorption↗

PubMed1994

Acute iron poisoning.

Acute iron poisoning continues to be one of the most common and deadly poisonings seen by emergency physicians. There are many potential pitfalls in the assessment, diagnosis, and treatment of iron-poisoned patients. This article reviews the pathophysiology of acute iron poisoning and describes a comprehensive management plan that will enable emergency physicians to provide appropriate emergency care to patients ingesting iron preparations. This article also addresses the common problems encountered by clinicians who care for iron-poisoned patients once they are admitted to the hospital.

Acute Disease↗

PubMed1992

Effect of glycol ethers on plasma osmolality.

1. Glycol ethers and their alkoxyacetic acid metabolites produce a linear increase in plasma osmolality with increasing plasma concentration. 2. This change in osmolality may be too small to be clinically useful at concentrations expected in cases of acute human glycol ether poisoning.

Adult↗

PubMed1991

Transplacental transport of N-acetylcysteine in an ovine model.

STUDY OBJECTIVE: Acetaminophen freely crosses the placenta, and acetaminophen ingestion is the most frequent intentional overdose in pregnancy. Although most patients do well after maternal treatment with the antidote N-acetylcysteine (NAC), fetal death with massive hepatic necrosis has occurred. It has never been shown whether NAC crosses the placenta to yield fetal plasma levels equal to those associated with hepatoprotective effects in human beings. Our study objective was to evaluate this in a widely accepted large animal model for maternal-fetal research. DESIGN AND TYPE OF PARTICIPANTS: A nonblinded experiment was performed using four domestic sheep at near-term gestation. INTERVENTIONS: NAC 150 mg/kg IV was administered to the ewe over 15 minutes. After induction of anesthesia, the fetal head was delivered surgically and a neck vein cannulated for blood sampling. Maternal and fetal blood samples were obtained at the end of NAC infusion, at 30- and then at 60-minute intervals for four hours. Plasma NAC levels were determined by gas chromatography/mass spectroscopy (detection limit, 2 micrograms/mL; quantification limit, 5 micrograms/mL). RESULTS: Maternal peak plasma NAC levels were 619, 631, 1,757, and 2,512, micrograms/mL, respectively, within 30 minutes of infusion. However, NAC was only minimally detectable in plasma of two fetal animals and transiently reached quantifiable levels in two others. None of the fetal animals attained serial plasma NAC levels that equalled those associated with therapeutic dosing or hepatoprotective effects in human beings. CONCLUSION: Transplacental transport of NAC is clinically insignificant in a mammalian model resembling the human being. These findings suggest that the human fetal liver is not protected from acetaminophen toxicity by maternal NAC therapy.

Acetylcysteine↗

PubMed1991

Digoxin-specific Fab fragments in the treatment of oleander toxicity in a canine model.

STUDY OBJECTIVE: To examine the efficacy of digoxin-specific Fab fragments (dsFab) in the treatment of experimentally induced Nerium oleander cardiac glycoside toxicity in a dog model. DESIGN: A nonblined, placebo-controlled experiment. SUBJECTS: Ten adult greyhound dogs of either sex divided into treatment and control groups of five dogs each. INTERVENTIONS: A tincture of oleander was prepared and administered intravenously to each animal. After the onset of cardiotoxicity, the treatment group received 60 mg/kg dsFab IV. MEASUREMENTS AND MAIN RESULTS: All dogs exhibited dysrhythmias meeting our criteria for cardiac glycoside cardiotoxicity within 27 minutes of beginning the infusion. Three of five control dogs had lethal dysrhythmias during the three-hour observation period. The remaining two control dogs exhibited dysrhythmias throughout the three-hour experiment. All five of the dsFab-treated dogs survived and converted to normal sinus rhythm within eight minutes of dsFab infusion. Three treatment animals reverted back to nonlethal and hemodynamically stable dysrhythmias after a mean of 107 minutes. CONCLUSION: Large doses of dsFab are efficacious in the treatment of dysrhythmias in this canine model of N oleander cardiac glycoside poisoning.

Animals↗

PubMed1991

Lack of evidence for a percent saturation gap in cyanide poisoning.

STUDY OBJECTIVES: To determine if toxic concentrations of cyanide in blood result in a difference between calculated and measured percent hemoglobin oxygen saturation (percent saturation gap). DESIGN: An in vitro laboratory study. SETTING: Hospital laboratory. TYPE OF PARTICIPANTS: Arterial blood from five stable patients residing in a tertiary hospital ICU. Venous blood samples obtained from five healthy volunteers. INTERVENTIONS: Two-mL aliquots from each blood sample were placed into four test tubes and mixed with phosphate buffer. Cyanide was added to three of the tubes so that the four tubes contained 0, 6, 12, and 25 mg/L cyanide. MEASUREMENTS AND MAIN RESULTS: The percent saturation gap was calculated by subtracting the percent oxyhemoglobin measured on an oximeter from the percent saturation calculated by a blood gas analyzer. Using two-tailed, paired t tests, we could not demonstrate a difference in mean percent saturation gaps between arterial samples or venous samples with and without cyanide. All blood samples had a normal percent saturation gap (P greater than .99 by Fisher's exact test). We had greater than a 95% chance of demonstrating a difference in mean percent saturation gaps of only 0.46% in arterial blood and of 3.3% in venous blood if such a difference existed. CONCLUSIONS: Our results, as well as a review of the literature, indicate that there are no data supporting the suggestion that a percent saturation gap should imply the diagnosis of poisoning by inorganic cyanide.

Adult↗

PubMed1991

Toxic effects of drugs used in the ICU. Nitroprusside, nitroglycerin, and angiotensin-converting enzyme inhibitors.

Sodium nitroprusside causes cyanide poisoning at currently recommended infusion rates. Serum thiocyanate concentrations are of no value in detecting cyanide poisoning caused by nitroprusside. Methemoglobinemia in those patients receiving intravenous nitroglycerin may seriously impair oxygen delivery and is not always accompanied by cyanosis in anemic patients. Angiotensin-converting enzyme inhibitors are responsible for a plethora of adverse effects, including renal insufficiency, hypotension, angioedema, cough, and increased insulin sensitivity.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1991

Refractory hypoglycemia secondary to topical salicylate intoxication.

We describe a case of severe refractory hypoglycemia secondary to topical salicylate intoxication. A 72-year-old man with psoriasis and end-stage renal disease was treated with a topical cream containing 10% salicylic acid. The patient presented with encephalopathy and subsequently developed hypoglycemia refractory to infusions of large amounts of glucose. A serum salicylate concentration was elevated at 3.2 mmol/L. Emergent hemodialysis was accompanied by rapid lowering of serum salicylate concentration and resolution of refractory hypoglycemia. Salicylate is well absorbed across normal and diseased skin. Salicylate markedly impairs gluconeogenesis and increases glucose utilization, resulting in hypoglycemia. To our knowledge, this is the first article on hypoglycemia due to the application of topical salicylate.

Administration, Cutaneous↗

PubMed1991

Lovastatin use and muscle damage in healthy volunteers undergoing eccentric muscle exercise.

We did a double-blind, placebo-controlled crossover study of 10 healthy young men taking no medications to determine if ingesting lovastatin is associated with more severe muscle damage after exercise. Five men in the first group took 40 mg of lovastatin daily for 30 days while those in the second group took an identical-appearing placebo. Each volunteer then walked downhill on a -14-degree incline on a treadmill at 3 km per hour for an hour. After a 2-week rest, the subjects were crossed over. Serial serum creatine kinase activity was measured immediately before and 8, 24, 48, 72, 120, and 144 hours after each treadmill session. With each subject serving as his own control, peak mean serum creatine kinase activity (/+- SEM) following treadmill after lovastatin therapy was similar to that following placebo (168.4 +/- 25.8 U per liter versus 146.7 +/- 14.7 U per liter, respectively [P = .9]). With an alpha value of .05, we had greater than a 99% chance of detecting a difference in the rise of serum creatine kinase activity of 200 U per liter between groups. Our data suggest that lovastatin is not an independent risk factor for developing exercise-induced muscle damage using this model of exercise in our study population.

Adult↗

PubMed1990

An ovine model of maternal iron poisoning in pregnancy.

An ovine model of maternal iron poisoning in pregnancy was used to examine the placental transport of deferoxamine and ferrioxamine and to follow maternal and fetal serum iron concentrations when maternal serum iron levels exceeded total iron-binding capacity. Ewes in the third stage of gestation underwent hysterotomy and delivery of the fetal head through an abdominal incision while under ketamine and halothane anesthesia. The fetal external jugular vein was catheterized for sampling of venous blood while the fetus remained in utero. Administration of deferoxamine mesylate or ferrioxamine mesylate IV to ewes was not accompanied by measurable deferoxamine or ferrioxamine in fetal blood. In a final experiment, four gravid ewes in a control group received 2 mg/kg maternal body wt iron IV over 60 minutes. An experimental group comprising another four ewes received similar doses of iron but then received 50 mg/kg deferoxamine mesylate IV over 15 minutes. Control and deferoxamine ewes reached similar peak maternal serum iron concentrations (2,479 +/- 266 and 2,121 +/- 343 micrograms/dL, respectively). The markedly elevated maternal serum iron concentrations were not accompanied by meaningful elevations in fetal serum iron levels over baseline values. Maternal deferoxamine infusion resulted in a more rapid fall in maternal serum iron concentrations but had no effect on fetal serum iron levels. The ovine fetus appears to be protected from elevated maternal serum iron concentrations in the last trimester of pregnancy. It could not be demonstrated that meaningful quantities of deferoxamine or ferrioxamine cross the placenta in the last trimester.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗