Christopher P. Holstege

CHEMICAL WARFARE: Nerve Agent Poisoning

The threat of civilian and military casualties from nerve agent exposure has become a greater concern over the past decade. After rapidly assessing that a nerve agent attack has occurred, emphasis must be placed on decontamination and protection of both rescuers and medical personnel from exposure. The medical system can become rapidly overwhelmed and strong emotional reactions can confuse the clinical picture. Initially, care should first be focused on supportive care, with emphasis toward aggressive airway maintenance and decontamination. Atropine should be titrated, with the goal of therapy being drying of secretions and the resolution of bronchoconstriction and bradycardia. Early administration of pralidoxime chloride maximizes antidotal efficacy. Benzodiazepines, in addition to atropine, should be administered if seizures develop. Early, aggressive medical therapy is the key to prevention of the morbidity and mortality associated with nerve agent poisoning.

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.

Metered-Dose Inhalers: Do Emergency Health Care Providers Know What to Teach?

STUDY OBJECTIVE To evaluate the ability of emergency health care providers and patients to demonstrate the proper use of metered-dose inhalers (MDIs). DESIGN Prospective cross-sectional survey. SETTING Five Midwestern community teaching hospitals. PARTICIPANTS One hundred eighty-five health care providers, comprising emergency medicine house staff (n = 60), attending emergency physicians (n = 50), and ED nurses (n = 75). Also recruited were 100 consecutive ED patients with clinical history of asthma being treated with at least one MDI for more than 3 months. INTERVENTIONS We surveyed patients and health care providers to assess their knowledge of and ability to use a conventional MDI. The subjects technique of using a placebo inhaler was graded by a trained observer using a checklist of six essential steps. RESULTS Forty-one percent (76 of 185) of health care providers and 49% (49 of 100) of ED asthma patients performed at least five steps correctly (P = .24). There were no significant differences in performance scores among the emergency medicine house staff (42%), attending emergency physicians (34%), and ED nurses (45%). Only 15% of all health care providers and 17% of asthma patients were able to describe how to estimate the amount of medicine left in the canister. CONCLUSION These results suggest that many patients use MDIs improperly. Emergency physicians, house staff, and nurses responsible for instructing patients in optimal inhaler use may lack even rudimentary skills with these devices.

Critical Care Toxicology

Emergency physicians are regularly called on to care for critically poisoned patients. This article reviews the general approach and management of the critically poisoned patient. Specific clinical characteristics are identified that may clue the clinician into a specific toxin class as a diagnosis. Appropriate testing in the poisoned patient is reviewed. Complications of poisoning that may bring a rapid demise of the critically ill poisoned patient are highlighted and the management of those complications is discussed.

Massive Caffeine Overdose Requiring Vasopressin Infusion and Hemodialysis

Abstract Introduction. Massive caffeine overdose is associated with life‐threatening hemodynamic complications that present challenges for clinicians. We describe the highest‐reported serum concentration of caffeine in a patient who survived and discuss the first‐reported use of vasopressin and hemodialysis in a caffeine‐poisoned patient. Case Report. A 41‐yr‐old woman presented 3 h after ingesting approximately 50 g of caffeine. She subsequently underwent cardiopulmonary resuscitation and received multiple medications in an attempt to raise her blood pressure and control her heart rate without success. Vasopressin infusion increased her blood pressure to the point where hemodialysis could be performed. Despite ensuing multisystem organ failure, she survived and has made a complete recovery. Conclusion. Hemodialysis and vasopressin infusions may be of benefit in the management of caffeine‐intoxicated patients who fail to respond to standard therapies.

Management of the critically poisoned patient

BackgroundClinicians are often challenged to manage critically ill poison patients. The clinical effects encountered in poisoned patients are dependent on numerous variables, such as the dose, the length of exposure time, and the pre-existing health of the patient. The goal of this article is to introduce the basic concepts for evaluation of poisoned patients and review the appropriate management of such patients based on the currently available literature.MethodsAn unsystematic review of the medical literature was performed and articles pertaining to human poisoning were obtained. The literature selected was based on the preference and clinical expertise of authors.DiscussionIf a poisoning is recognized early and appropriate testing and supportive care is initiated rapidly, the majority of patient outcomes will be good. Judicious use of antidotes should be practiced and clinicians should clearly understand the indications and contraindications of antidotes prior to administration.

Cost-benefit analysis of a regional poison center

Background. Funding poison center (PC) operations has become a major challenge nationwide. Increasingly, state and federal budget cuts have resulted in diminished funding to PCs. Objectives. In an effort to demonstrate the value of current PC phone services, a cost-benefit analysis of a regional center was completed. Methods. A telephone survey was used to collect data from PC callers during an 8-week period in 2004. Callers with human exposure poisonings determined by the PC to be of minimal or no risk were asked to complete the phone survey. Callers were asked their alternative plan if the PC staff had not been available to assist them. Benefits were measured as healthcare charges potentially avoided. Results: A total of 652 caller surveys were completed. The benefit-to-cost ratio was 7.67 (95% C.I. 6.83, 8.50). Conclusion. In addition to non-monetary benefits, the operation of a regional poison center provides significant positive return on investment.

Verapamil Toxicity Dysregulates the Phosphatidylinositol 3‐Kinase Pathway

OBJECTIVES Recent animal research and clinical case reports suggest benefit from high-dose insulin therapy (HDIT) for the treatment of calcium channel blocker (CCB) toxicity. One molecular signaling pathway, the phosphatidylinositol 3-kinase (PI3K) pathway, that contributes to CCB toxicity and the efficacy of HDIT, was examined for a role in this phenomenon. METHODS A differentiated 3T3-L1 adipocyte model system was utilized to characterize metabolic and molecular signaling events dysregulated in response to acute CCB toxicity. Glucose uptake assays were performed in the presence of representatives of three classes of CCB drugs, and the ability of HDIT to reverse observed inhibition was assessed. Western blot analyses were utilized to probe which insulin-dependent signaling pathway was inhibited by CCB toxicity. RESULTS Representative compounds from the dihydropyridine and phenylalkylamine classes of CCBs were more effective at inhibiting glucose uptake in differentiated 3T3-L1 adipocytes than a representative from the benzothiazepine class. Phosphorylation at serine 473 of the Akt protein (P-Akt), a protein representing a common pathway for insulin receptors (IR), insulinlike growth factor receptors (IGFR), and hybrid receptors formed by IR and IGFR subunits, was abolished in the presence of toxic doses of the phenylalkylamine CCB verapamil. Phosphorylation at serine 473 of Akt was rescued in the presence high concentrations of insulin. CONCLUSIONS These data suggest that dysregulation of the insulin-dependent PI3K pathway is partially responsible for insulin resistance and the hyperglycemic state observed in response to acute CCB toxicity.

Accuracy of Internet Recommendations for Prehospital Care of Venomous Snake Bites

OBJECTIVE To evaluate the accuracy of Internet information regarding the prehospital care of venomous snake bites. METHODS Two major search engines were used to identify 48 Web sites regarding 6 prehospital treatment options for snake bite (removal of constrictive devices, ice, heat, electric shock, incision, and suction). Web sites were evaluated for their quality using the Health on the Net (HON) seal and Journal of the American Medical Association (JAMA) benchmarks. RESULTS Of the 48 Web sites reviewed, 26 (54.1%) contained inappropriate recommendations. The remaining 22 Web sites were appropriate regarding all modalities addressed. Among the Web sites reviewed, inappropriate treatment recommendations included: suction (14); ice (6); incision (4); electric shock (1). Five Web sites that met all 4 JAMA benchmarks and the HON seal included 3 inappropriate treatment recommendations. Conversely, the 5 Web sites that met none of the JAMA benchmarks nor included the HON seal included only 2 inappropriate treatment measures. CONCLUSION This study highlights the variety of misinformation available on the Internet regarding prehospital care of snake bites, and the unreliability of the HON seal and JAMA benchmarks as markers of accuracy. As the Internet becomes an increasing source of medical information for both the public and clinicians, the importance of accurate Web sites becomes imperative. Clinicians and lay people should be aware of the high variability of Internet information regarding snake bite prehospital care.

Injury and Illness Encountered in Shenandoah National Park

Abstract Objective.—There have been no studies to date exploring the nature of injuries and illness experienced by individuals in a National Park in the southeastern United States. The purpose of this study was to determine the incidence of such illnesses and injuries to visitors in Shenandoah National Park. Methods.—This study was a retrospective review of the case incident reports from Shenandoah National Park from 2003 to 2007. Data obtained included age, sex, time and date report was received, medical symptoms, trauma type, location of injury, mechanism of injury, level of care, time to patient, time to disposition, disposition type, location, and activity at time of event. Results.—There were 159 total cases, corresponding to a reported incident rate of 2.7 persons reported injured or ill per 100 000 visitors to Shenandoah National Park. A total of 23.3% of all reported injuries occurred in persons less than 18 years of age. The most common reported adult injury was soft tissue injury, with the most common anatomical location being the distal lower extremity. The most common activity in which adults were involved at the time of the injury was hiking. Of the pediatric trauma cases, the most common mechanism of injury was a fall. Of the adult medical illnesses, the most common complaint was chest pain. Conclusions.—The pattern of adult and pediatric trauma is consistent among several geographically different National Parks in the United States and represents an injury pattern that all wilderness/outdoor care providers need to be competent to treat. Among adult visitors, the most common medical complaint was chest pain, a complaint more prevalent at Shenandoah National Park compared to other parks. Knowing that trauma injury patterns are relatively similar to those of other parks but that medical illness is more locale specific can help health care providers tailor their resource allotment and health management protocols.