Biomedical subjects

Richard F Clark

Publications and source records attributed to Richard F Clark.

43 records · Page 3Linked to original sources

PubMed2002

Delayed valproic acid toxicity: a retrospective case series.

STUDY OBJECTIVE: We estimate how often an initially undetectable or nontoxic valproic acid (VPA) concentration misrepresents the potential toxicity of an acute VPA overdose. METHODS: All patients followed up by the San Diego and San Francisco Divisions of the California Poison Control System between January 1997 and June 1999 with a documented serum VPA concentration of 120 microg/mL or greater at any time were identified through a search of poison center databases. Cases involving patients who had serial VPA concentrations and an initial VPA concentration that was unmeasurable or less than 100 microg/mL were also identified. The methods of decontamination, clinical outcomes, highest measured concentration, and times after ingestion of the initial and highest measured concentration of VPA were determined by means of chart review for these cases. RESULTS: Of the 173 patients identified with VPA concentrations of 120 microg/mL or greater, 21 (12.1%) had a detectable initial concentration not in the toxic range, and 5 (2.9%) had initial concentrations of less than the limit of detection. These 26 cases involved acute ingestion of VPA preparations. Four of these 26 patients were discharged to home or to a psychiatric facility after the initial results were obtained. CONCLUSION: Delayed toxicity might occur in patients after an acute overdose of enteric-coated VPA. Initial serum VPA concentrations might be misleading. Serial measurements documenting declining VPA concentrations or prolonged observation are recommended to determine whether a patient is medically safe for discharge or psychiatric placement.

Adolescent↗

PubMed2002

A prospective study of acute, unintentional, pediatric superwarfarin ingestions managed without decontamination.

STUDY OBJECTIVE: We determine the incidence of clinically important bleeding in children with superwarfarin rodenticide ingestions not treated with gastrointestinal decontamination or prophylactic vitamin K. METHODS: We prospectively studied patients younger than 6 years of age who reported to our poison center with acute unintentional superwarfarin ingestions. Patients who received gastrointestinal decontamination or prophylactic vitamin K were excluded. Forty-eight- to 96-hour prothrombin time or international normalized ratio (INR) blood tests were recommended, and telephone contact was attempted at least 3 days after ingestion. RESULTS: A total of 595 consecutive patients were enrolled during the 16-month study period. Fifty patients were excluded: 8 who were known to have ingested 1 pellet or less; 25 who received activated charcoal; 15 who were treated with induced emesis; and 2 who received prophylactic vitamin K. The resulting study group contained 545 patients. Eighty-two patients were lost to follow-up. Follow-up was obtained for 463 patients, including 222 by telephone contact alone, 62 by 48- to 96-hour INR, and 179 by both methods. None of the patients had clinically important coagulopathy. Two patients had an INR of 1.5 or greater (1.5 and 1.8) without symptoms. Single nosebleeds were reported in another 2 patients with normal 48-hour INRs. Another child had a small amount of blood crusted in the nose with no other symptoms and no laboratory work available. One child with a normal 48-hour INR had blood-streaked stools that were thought to be caused by an anal fissure. CONCLUSION: Children with acute unintentional superwarfarin ingestions of less than 1 box may be managed without gastric decontamination or prophylactic vitamin K. Laboratory testing for coagulopathy should be reserved for cases involving clinically evident bleeding abnormalities.

4-Hydroxycoumarins↗

PubMed2002

Massive OxyContin ingestion refractory to naloxone therapy.

OxyContin (oxycodone hydrochloride controlled release) is a long-acting preparation of oxycodone that is used as an opioid analgesic to treat chronic pain conditions. We report a patient who ingested a massive quantity of OxyContin and had altered mental status, noncardiogenic pulmonary edema, and hypoventilation that proved refractory to naloxone administration. She required mechanical ventilation for 3 days before recovering completely. The severity and length of poisoning was likely related both to the quantity and formulation of the oxycodone ingested.

Female↗

PubMed2002

Evaluating the utilization of a regional poison center by Latino communities.

BACKGROUND: Penetrance values estimate the utilization of poison centers services. For a variety of reasons, penetrance values may vary greatly among geographic areas of population. We examined the relationship between ethnicity and penetrance in our population. METHODS: We conducted a retrospective review of data from January 1, 2000 through December 31, 2000 from our poison center's database. Home calls to the center were evaluated by zip code, age, gender, substance, route of exposure, and outcome. These data were compared with U.S. Census 2000 geographic and community demographic data for San Diego by zip code. From this information, we identified zip code regions with substantial Latino populations (>50%), and substantial Caucasian populations (>70%). Study groups were limited to those zip codes with median household incomes of $20,000-$50,000. Aggregate total and pediatric penetrance values were calculated for each group and compared. RESULTS: Our study group consisted of 6 zip codes with significant numbers of Latino residents, and 11 zip codes with significant numbers of Caucasian residents. Aggregate call volume for the county was 6.5 calls per 1000 population, while that for children less than age 5 was 43. Penetrance values for the study zip codes with large Latino populations were significantly lower with a mean value of 22.4 for children, and 5.0 for all ages. These values were statistically significant when compared to county data and that from the control zip codes with largely Caucasian residents (61 aggregate and 49.6 pediatric). CONCLUSION: Penetrance values were significantly lower in zip codes with large numbers of Latino residents. Reasons for this variation are being investigated.

California↗

PubMed2002

Crotaline Fab antivenom for the treatment of children with rattlesnake envenomation.

OBJECTIVE: There is little data regarding safety or efficacy of Crotalinae polyvalent immune Fab (ovine) antivenom (crotaline Fab) in pediatric patients. Our objective was to provide the first information regarding safety and effectiveness of this new drug in children. METHODS: Data were collected prospectively and retrospectively for all consecutive pediatric patients bitten by rattlesnakes and treated at 2 urban hospitals during 2001. Cases were included if there were signs of envenomation at presentation, patient age was 13 years or less, and there was administration of crotaline Fab. Cases were excluded if antivenin (Crotalidae) polyvalent (equine origin, the conventional antivenom) was given. Primary outcome variables were snakebite severity scores throughout the course of therapy, number of vials of crotaline Fab administered, occurrence of allergic reactions, adjunct surgical therapy, and the presence of permanent sequelae or serum sickness identified at follow-up. RESULTS: In the 12 cases studied, ages ranged from 14 months to 13 years (mean: 6.9; standard deviation: 4.2). Presentation snakebite severity scores ranged from 2 to 9 (mean: 5.3; standard deviation: 2.3). Total crotaline Fab doses ranged from 4 to 22 vials (mean: 12.7; standard deviation: 5.4). Initial control of symptoms was achieved with 4 to 16 vials (mean: 7.7; standard deviation: 3.7), and severity scores stabilized or improved within 24 hours in all patients. Recurrence of local swelling occurred in 1 case despite scheduled repeat doses of antivenom. No cases required surgical intervention, and no permanent sequelae were identified. No immediate or delayed hypersensitivity reactions occurred. CONCLUSION: In this group of pediatric patients treated for rattlesnake envenomation, crotaline Fab antivenom was safe and seemed to be effective.

Adolescent↗

PubMed2002

The effect of oleoresin capsicum "pepper" spray inhalation on respiratory function.

We performed a randomized, cross-over controlled trial to assess the effect of Oleoresin capsicum (OC) spray inhalation on respiratory function by itself and combined with restraint. Thirty-five subjects were exposed to OC or placebo spray, followed by 10 min of sitting or prone maximal restraint position (PMRP). Spirometry, oximetry, and end-tidal CO2 levels were collected at baseline and throughout the 10 min. Data were compared between groups (ANOVA) and with predefined normal values. In the sitting position, OC did not result in any significant changes in mean percent predicted forced vital capacity (%predFVC), percent predicted forced expiratory volume in 1 s (%predFEV1), oxygen, or CO2 levels. In PMRP, mean %predFVC and %predFEV1 fell 14.4 and 16.5% for placebo and 16.2 and 19.1% for OC, but were not significantly different by exposure. There was no evidence of hypoxemia or hypercapnia in either groups. OC exposure did not result in abnormal spirometry, hypoxemia, or hypoventilation when compared to placebo in either sitting or PMRP.

Adult↗

PubMedDate not supplied

Antidote use in the critically ill poisoned patient.

The proper use of antidotes in the intensive care setting when combined with appropriate general supportive care may reduce the morbidity and mortality associated with severe poisonings. The more commonly used antidotes that may be encountered in the intensive care unit (N-acetylcysteine, ethanol, fomepizole, physostigmine, naloxone, flumazenil, sodium bicarbonate, octreotide, pyridoxine, cyanide antidote kit, pralidoxime, atropine, digoxin immune Fab, glucagon, calcium gluconate and chloride, deferoxamine, phytonadione, botulism antitoxin, methylene blue, and Crotaline snake antivenom) are reviewed. Proper indications for their use and knowledge of the possible adverse effects accompanying antidotal therapy will allow the physician to appropriately manage the severely poisoned patient.

Antidotes↗