Secondary exposure of medical staff to sarin vapor in the emergency room

Does position of the patient adversely affect successful intubation whilst wearing CBRN-PPE?

INTRODUCTION

Following a CBRN incident attending medical personnel will be required to instigate life saving airway interventions whilst wearing CBRN-PPE. CBRN-PPE is known to adversely affect fine motor skill but little is known about whether the position of the patient compounds this problem.

METHODS

Seventy-five clinicians were recruited and performed intubation and insertion of a LMA in to a manikin whilst wearing CBRN-PPE. Both skills were completed twice with the manikin positioned on a bench and once on the floor. Following completion of the study 25 participants (a minimum of 2 participants from each professional group) were interviewed to ascertain their experiences. The recruitment of a non-homogenous group allowed for subgroup analysis with regards the potential impact of professional background on skill performance.

RESULTS

9.33% first attempts at intubation at waist height ended in failure but this reduced to 4% on the second attempt. This improvement was reversed with the manikin on the floor where the failure rate was 26.67%. Intubation on the floor took significantly longer to perform, being 45.9 s slower than the first attempt at intubation in the optimal position [95% CI (30.7 s, 61.1 s); p<0.001] and 62.4 s longer than the second [95% CI (48.4 s, 76.3 s); p<0.001]. LMA insertion was successful at all attempts, regardless of the manikins position. LMA placement on the floor was no slower than the second attempt at waist height (p=0.231) and faster than the first attempt at waist height (by 4.8 s [95% CI (3.4 s, 6.1 s); p<0.001]). Anaesthetists were consistently the fastest at performing all airway skills regardless of the position of the manikin but previous exposure to wearing CBRN-PPE had no statistically significant impact on skill performance. All 25 clinicians interviewed had difficulty in viewing the larynx with the manikin positioned on the floor regardless of being an experienced 'on floor' intubator with the movement of the CBRN-PPE hood being the principle reason. This is in contrast to only three participants noting issues with vision whilst standing-up.

CONCLUSION

the position of the patient is likely to be an independent factor when choosing to either intubate or insert a LMA whilst wearing the current NHS CBRN-PPE.

Nerve agent exposure elicits site-specific changes in protein phosphorylation in mouse brain

Organophosphorus (OP) compounds cause toxic symptoms, including convulsions, coma, and death, as the result of irreversible inhibition of acetylcholinesterase (AChE). The development of effective treatments to block these effects and attenuate long-term cognitive and motor disabilities that result from OP intoxication is hampered by a limited understanding of the CNS pathways responsible for these actions. We employed a candidate method (called CNSProfile) to identify changes in the phosphorylation state of key neuronal phosphoproteins evoked by the OP compound, diisopropyl fluorophosphate (DFP). Focused microwave fixation was used to preserve the phosphorylation state of phosphoproteins in brains of DFP-treated mice; hippocampus and striatum were analyzed by immunoblotting with a panel of phospho-specific antibodies. DFP exposure elicited comparable effects on phosphorylation of brain phosphoproteins in both C57BL/6 and FVB mice. DFP treatment significantly altered phosphorylation at regulatory residues on glutamate receptors, including Serine897 (S897) of the NR1 NMDA receptor. NR1 phosphorylation was bi-directionally regulated after DFP in striatum versus hippocampus. NR1 phosphorylation was reduced in striatum, but elevated in hippocampus, compared with controls. DARPP-32 phosphorylation in striatum was selectively increased at the Cdk5 kinase substrate, Threonine75 (T75). Phencynonate hydrochloride, a muscarinic cholinergic antagonist, prevented seizure-like behaviors and the observed changes in phosphorylation induced by DFP. The data reveal region-specific effects of nerve agent exposure on intracellular signaling pathways that correlate with seizure-like behavior and which are reversed by the muscarinic receptor blockade. This approach identifies specific targets for nerve agents, including substrates for Cdk5 kinase, which may be the basis for new anti-convulsant therapies.

Evaluation of bag-valve-mask ventilation by paramedics in simulated chemical, biological, radiological, or nuclear environments

INTRODUCTION

Bag-valve-mask ventilation is a key component of life support, but only one handheld resuscitator is designed to operate in contaminated or toxic atmospheres.

METHODS

After Institutional Review Board approval, the efficacy of this device was evaluated. The distal trachea of a Laerdal Airway Management Trainer was connected to a mechanical Draeger Volumeter 3000, to enable determination of the minute volume delivered by BVM ventilation. Nineteen paramedics wearing chemical, biological, radiological, or nuclear (CBRN) protective equipment were asked to ventilate this modified airway trainer, either with or without a CBRN filter attached to the inlet filtration system of the AMBU Mark III Resuscitator. The maximum levels of minute ventilation achieved were compared. Values are given as mean +/-SD. A paired t-test was used to detect any differences between the two groups, p-values of <0.05 were defined to show statistical significance.

RESULTS

The described model allowed a reproducible and reliable measurement of the delivered minute ventilation. All paramedics were able to operate the device without prior CBRN training. The maximum minute volume achieved without the filter was 9.5 +/-2.7 l/min. Use of the inlet CBRN filtration system reduced the maximum minute volume to 6.3 +/-2.0 l/min, reduction: 23%. The achieved maximum minute volumes ranged from 15 to 4.9 l/min in the controls and from 9.8 to 1.4 l/min in the CBRN group. Four paramedics were unable to achieve a minute volume >5 l/min in the CBRN group, one participant failed to achieve that value in the control group. The inherent breathing resistance of the CBRN filter appears to reduce the inflow of air into the self-inflatable bag. This delay in refilling may have resulted in a reduced achievable minute volume.

CONCLUSIONS

The range of maximum minute volumes observed in both groups highlights the need for continuous BVM ventilator training.

The comprehensive medical preparedness in chemical emergencies: 'the chain of chemical survival'

Medical management of victims of chemical incidents includes supportive therapy, decontamination and antidote administration. Chemical weapons of mass destruction are available to many countries and are a possible alternative to conventional weapons for terrorist groups. During the last 5 years, some Italian institutions have made big efforts to establish a national system of antidote stockpiling and distribution. Little or no efforts have been addressed to other aspects of the medical management of patients exposed to chemical agents, such as decontamination, personal protective equipment, and specific supportive therapy. Although antidotes are indispensable instruments for some poisonings, as nerve agent and botulin intoxication, antidote stockpiling cannot be considered the only objective of a comprehensive medical preparedness for chemical emergencies. This paper addresses the medical priority when approaching victims of chemical emergencies. The priority actually is to establish a chain of chemical survival in which antidote administration is one out of several links.

Respiratory protection during high-fidelity simulated resuscitation of casualties contaminated with chemical warfare agents

Emergency room personnel are threatened by secondary poisoning when treating victims affected by chemical warfare agents. Therefore, resuscitation skills practised with respiratory protection equipment in place require evaluation. We investigated the influence of wearing air-purifying respirators on the simulated resuscitation of chemical warfare agent casualties. We studied 22 anaesthetic trainees in a simulated resuscitation scenario requiring five set tasks, either unprotected, wearing a binocular visor respirator or a panoramic visor respirator in a randomised, crossover study. Treatment times did not differ between the three groups, with mean (SD) times to complete the tasks being 122 (8) s without a mask, 126 (7) s when wearing the panoramic visor mask and 129 (8) s when wearing the binocular respirator mask. All anaesthetists preferred the panoramic visor in terms of visual orientation but 88% of them rated the binocular mask as being more comfortable. Modern respirators have a negligible effect on simulated resuscitation scenarios for victims affected by chemical warfare agents. Panoramic visor respirators allow better visual orientation for anaesthetists during simulated resuscitation.

Hand-held photoionization instruments for quantitative detection of sarin vapor and for rapid qualitative screening of contaminated objects

Suitable detectors are needed to support survey needs of incident responders and health care personnel who may receive patients from an incident with exposures to hazardous chemicals. In the health care setting, such a detector would avoid cross-contamination to workers, patients, and to the treatment facility and associated equipment. An ideal survey detector would be sensitive, hand-held, capable of extended battery operation, and would provide a nearly immediate detector response on exposure to a broad range of high-concern chemicals. For responders, important capabilities would include quantitative measurement of gas/vapor contamination, and for both response and health care settings, qualitative detection of contaminated people and objects. In this study, the operating characteristics of photoionization detector (PID) instruments were examined using O-isopropyl methylphosphonofluoridate (sarin) in a laboratory setting. Instrument response factors were calculated for quantitation of airborne sarin, and speed of detector response and recovery were examined with point-contaminated cloth material. By sampling a range of sarin-contaminated air, calculated isobutylene unit response factors for high-and moderate-sensitivity commercial PID instrument types were 11.3 and 14.0 (dry air) and 20.1 and 44.4 (50% relative humidity), respectively. Response of the PID systems was highly correlated to concentration sampled, with R(2) values greater than or equal to 0.997 for all combinations of PID detector type and humidity. While not sensitive enough to warn the unprotected public against a chemical with an extremely low "safe" exposure concentration, quantitation with available PID instruments could be useful to quickly prioritize corrective measures for a PID-detectable chemical. Qualitative survey characteristics were examined for the more sensitive PID tested using a piece of cloth material contaminated by a 1.0 micro L droplet of liquid sarin. Rapid response and recovery times (seconds) were observed when the sampling inlet was moved close to and away from the point of contamination. Within the health care setting, hand-held PID instruments could fill an important and currently unmet need as a point source detector for liquid contamination from extremely dangerous chemicals to help identify contaminated surfaces and limit secondary contamination and exposures.

Disasters and mass casualties: II. explosive, biologic, chemical, and nuclear agents

Terrorists' use of explosive, biologic, chemical, and nuclear agents constitutes the potential for catastrophic events. Understanding the unique aspects of these agents can help in preparing for such disasters with the intent of mitigating injury and loss of life. Explosive agents continue to be the most common weapons of terrorists and the most prevalent cause of injuries and fatalities. Knowledge of blast pathomechanics and patterns of injury allows for improved diagnostic and treatment strategies. A practical understanding of potential biologic, chemical, and nuclear agents, their attendant clinical symptoms, and recommended management strategies is an important prerequisite for optimal preparation and response to these less frequently used agents of mass casualty. Orthopaedic surgeons should be aware of the principles of management of catastrophic events. Stress is less an issue when one is adequately prepared. Decontamination is essential both to manage victims and prevent further spread of toxic agents to first responders and medical personnel. It is important to assess the risk of potential threats, thereby allowing disaster planning and preparation to be proportional and aligned with the actual casualty event.

Influence of air-purifying respirators on the simulated first response emergency treatment of CBRN victims

AIM

Medical first responders and emergency room personnel potentially are threatened by exposure to primary or secondary intoxication by chemical, biological, radiological or nuclear (CBRN) substances. The impact of personal respiratory protection by air-purifying respirators on the performance of resuscitation requires evaluation. This will help to improve major incident planning and measures for protecting medical staff.

METHODS

We investigated the influence of two air-purifying respirator designs on the resuscitation of simulated CBRN victims. Fourteen UK paramedics followed a standardised resuscitation algorithm, either unprotected or wearing a bi-ocular and a panoramic visor respirator in a randomised crossover design. Treatment times and wearer comfort was determined and compared.

RESULTS

We did not find any difference in treatment times between the groups wearing respiratory protection and the controls (189+/-8.3s for the controls, 191+/-9.5s for the panoramic visor mask and 206+/-9.1s for the bi-ocular respirator [mean+/-S.E.M.]). Tracheal intubation appeared to be the most time consuming task. In a questionnaire, volunteers were of the opinion that orientation whilst wearing the respirator with the panoramic visor was better compared to the bi-ocular one (85% versus 15%). With respect to the fit, the majority (79%) rated the bi-ocular respirator as more comfortable.

CONCLUSIONS

Modern personal respiratory protection has only a negligible effect in the delay on the short term treatment during well defined simulated scenarios with a single CBRN casualty. Furthermore, air-purifying respirators with panoramic visors seem to allow a better orientation for medical first responders during simulated resuscitation.

Emergency department personal protective equipment requirements following out-of-hospital chemical biological or radiological events in Australasia

Recent events have led to a revision in ED equipment, preparedness and training for disasters. However, clinicians must still decide when, and what level of personal protection is required when a toxic threat exists. If possible, clear, simple and achievable protocols are required in such situations. Following an off‐site Australasian chemical biological or radiological incident, current evidence indicates that the initial receiving ED staff will be adequately protected from all known chemical biological and radiological inhalational threats by wearing a properly fitted P2 (N95) mask, or its equivalent. Protection from serious contact injury is offered by wearing double gloves, disposable fluid‐repellent coveralls or gown, eye protection, surgical mask, and ideally, a cap and shoe covers; in conjunction with universal precautions and procedures.

Respiratory protection for Health Care Workers

Chemical, Biological, Radiological and Nuclear incidents are rare, but the likelihood of any medical facility having to deal with contaminated or contagious casualties is not, Health Care Workers (HCW) often being exposed to infectious or toxic substances. Although medical staff routinely take measures to protect themselves against exposure to infection by wearing protective clothing, they rarely consider the inhalational route as a threat. This paper presents a series of cases where HCW's have been exposed to toxic or infectious material through the respiratory route, discusses standards of respiratory protection and describes how this risk can be mitigated to protect medical personnel.

Emergency department staff can effectively resuscitate in level C personal protective equipment

OBJECTIVE

ED staff are expected to perform resuscitation of trauma victims of chemical, biological and radiation incidents while wearing level C personal protective equipment (PPE). The present project assessed the subjective discomfort, physiological impact and performance of staff wearing PPE.

METHODS

A paired intervention study of ED staff in a resuscitation scenario comparing task performance wearing gown and gloves with PPE. Data were collected using a structured self-administered questionnaire and by objective and subjective measurements.

RESULTS

Seven ED doctors and 11 ED nurses were enrolled. Nine had previous PPE training although only one had used PPE clinically. Overall, ED staff felt that PPE did not affect their ability to perform trauma resuscitation. For individual tasks, staff felt that PPE impaired assessment of pulse, i.v. cannulation, i.v. line attachment, use of a mini-jet, bag and mask ventilation, and communication. However, the only objective difference in task performance was time to control haemorrhage (increase from 38 to 47 s, P = 0.02). PPE was well tolerated, with minimal physiological or psychological impact. Staff wore PPE for a median of 37 min (interquartile range: 33-38) and estimated that PPE could be worn for a further 30 min if required.

CONCLUSIONS

ED staff are able to perform resuscitation procedures in PPE without adverse physiological effects or impact on performance. Subjective concerns regarding task performance were not reflected in objective measurements. This might indicate that appropriate training and feedback could reduce the negative impression associated with activities undertaken while wearing PPE.

The acute treatment of nerve agent exposure

Nerve agents (NA) are simple and cheap to produce but can produce casualties on a massive scale. They have already been employed by terrorist organizations and rogue states on civilians and armed forces alike. By inhibiting the enzyme acetylcholine esterase, NAs prevent the breakdown of the neurotransmitter acetylcholine. This results in over-stimulation of muscarinic and nicotinic receptors in the autonomic and central nervous systems and at the neuromuscular junction. Increased parasympathetic stimulation produces miosis, sialorrhea, bronchospasm and bronchorrhea. Effects at the neuromuscular junction cause weakness, fasciculations, and eventually paralysis. Central effects include altered behavior and mental status, loss of consciousness, seizures, or apnea. Most deaths are due to respiratory failure. Treatment with atropine competitively blocks the parasympathetic effects. Oximes like pralidoxime salvage acetylcholine esterase by "prying off" NA, provided the attachment has not "aged" to an irreversible bond. This reverses weakness. Benzodiazepines like diazepam are effective against NA induced seizures. Mortality has been surprisingly low. If victims can survive the first 15 to 20 min of a vapor attack, they will likely live. The low mortality rate to date underscores that attacks are survivable and research reveals even simple barriers such as clothing offer substantial protection. This article reviews the properties of NAs and how to recognize the clinical features of NA intoxication, employ the needed drugs properly, and screen out anxious patients who mistakenly believe they have been exposed.

Recognition of illness associated with covert chemical releases

Public health threats from intentional releases of chemicals into the environment (ie, chemical terrorism) are an increasing concern in the United States. Recent situations of deliberate contamination of food and beverages with chemicals highlight the need for health care providers and public health officials to be alert for adult and pediatric patients in their communities who have signs and symptoms consistent with chemical exposures. In an effort to increase knowledge of surveillance and preparedness for illness related to potential chemical releases, we provide guidance to health care providers and public health personnel for recognizing illnesses or patterns of illnesses that might be associated with the intentional, covert release of chemical agents. In this article, we will discuss 5 examples of outbreaks of illnesses after a covert chemical release, obstacles to recognition of these illnesses, clues (ie, epidemiological patterns and syndromic presentations) that might enhance the recognition of illnesses from a covert chemical release, and public health strategies to enhance the rapid identification of a chemical terrorism event.

Acute pesticide-related illness among emergency responders, 1993-2002

BACKGROUND

Emergency responders are among the first to arrive at a pesticide-related release event. Magnitude, severity, and risk factor information on acute pesticide poisoning among those workers is needed.

METHODS

Survey data collected from the SENSOR-Pesticides, CDPR and HSEES programs between 1993 and 2002 from 21 states were reviewed. Acute occupational pesticide-related illness incidence rates for each category of emergency responder were calculated, as were incidence rate ratios (IRR) among emergency responders compared to all other workers employed in non-agricultural industries.

RESULTS

A total of 291 cases were identified. Firefighters accounted for 111 cases (38%), law enforcement officers for 104 cases (36%), emergency medical technicians for 34 cases (12%), and 42 cases (14%) were unspecified emergency responders. Among the 200 cases with information on activity responsible for exposure, most were exposed while performing activities related to a pesticide release event (84%) and not involving patient care, while the remainder involved exposure to pesticide-contaminated patients. A majority of cases were exposed to insecticides (51%). Most had low severity illnesses (90%). The incidence rate was highest for firefighters (39.1/million) and law enforcement officers (26.6/million). The IRRs were also elevated for these professions (firefighters, IRR = 2.67; law enforcement officers, IRR = 1.69).

CONCLUSIONS

The findings suggest the need for greater efforts to prevent acute occupational pesticide-related illness among emergency responders.

Availability, stability, and sterility of pralidoxime for mass casualty use

STUDY OBJECTIVE

Pralidoxime is indicated to treat patients poisoned with nerve agents. It is available in intravenous formulation for more seriously ill hospitalized patients and intramuscular formulation for field treatment and less seriously ill patients. Our study describes a method to convert the intramuscular formulation for intravenous use and determines the stability and sterility of the resulting formulation over time and under various environmental conditions.

METHODS

An inventory was taken of all intravenous (Protopam) and intramuscular (Mark I Autoinjector kits) pralidoxime available in Franklin County, Ohio hospitals, and out-of-hospital stockpiles. A method was devised to safely convert the intramuscular pralidoxime to an intravenous formulation, which was then tested for stability and sterility under a variety of environmental temperatures over time.

RESULTS

In Franklin County, Ohio (population 1.1 million), the 10 acute care hospitals and out-of-hospital community have 36 g of intravenous pralidoxime and 4,398 g (7,270 Mark I kits) of intramuscular pralidoxime. The reformulated pralidoxime retained greater than 90% stability and remained sterile at all environmental temperatures through day 28.

CONCLUSION

Available pralidoxime in Franklin County is predominantly in the intramuscular preparation. Conversion of intramuscular to intravenous pralidoxime results in a stable and sterile solution for up to 28 days under a variety of environmental conditions and should be considered in a mass casualty situation in which additional intravenous supplies are needed.

A novel apparatus for non-contact measurement of heart rate variability: a system to prevent secondary exposure of medical personnel to toxic materials under biochemical hazard conditions, in monitoring sepsis or in predicting multiple organ dysfunction syndrome

BACKGROUND

The impaired balance of the low-frequency/high-frequency ratio obtained from spectral components of RR intervals can be a diagnostic test for sepsis. In addition, it is known that a reduction of heart rate variability (HRV) is useful in identifying septic patients at risk of the development of multiple organ dysfunction syndrome (MODS). We have reported a non-contact method using a microwave radar to monitor the heart and respiratory rates of a healthy person placed inside an isolator or of experimental animals exposed to toxic materials.

APPARATUS DESIGN AND TESTING

With the purpose of preventing secondary exposure of medical personnel to toxic materials under biochemical hazard conditions, we designed a novel apparatus for non-contact measurement of HRV using a 1215 MHz microwave radar, a high-pass filter, and a personal computer. The microwave radar monitors only the small reflected waves from the subject's chest wall, which are modulated by the cardiac and respiratory motion. The high-pass filter enhances the cardiac signal and attenuates the respiratory signal. In a human trial, RR intervals derived from the non-contact apparatus significantly correlated with those derived from ECG (r=0.98, P<0.0001). The non-contact apparatus showed a similar power spectrum of RR intervals to that of ECG.

CONCLUSIONS

Our non-contact HRV measurement apparatus appears promising for future pre-hospital monitoring of septic patients or for predicting MODS patients, inside isolators or in the field for mass casualties under biochemical hazard circumstances.

Pharmacists in the Omaha Metropolitan Medical Response System

PURPOSE

The role of pharmacists in the Metropolitan Medical Response System (MMRS) for Omaha, Nebraska, is described.

SUMMARY

Pharmacists have been involved in the Omaha MMRS since its inception in 2000. The Omaha MMRS has a pharmacy committee composed of pharmacists from local hospitals, community pharmacies, and two pharmacy schools. The pharmacy committee oversees the stock of pharmaceuticals available to Omaha in an emergency by continuously monitoring hospital inventories and working with state and federal planners. Pharmacists are responsible for planning for the receiving, staging, storing, distributing, and dispensing of the large quantities of pharmaceuticals that might be required in a disaster. Pharmacists also educate other health care professionals and the public about threats.

CONCLUSION

Pharmacists play a major role in emergency preparedness in the Omaha metropolitan area and would be active participants in the community's response to a disaster.

Emergency preparedness for biological and chemical incidents: a survey of anesthesiology residency programs in the United States

We surveyed health care professionals about their preparations to manage the clinical problems associated with patients exposed to hazardous substances, including weapons of mass destruction (WMD). Training for WMD is considered a key part of public health policy and preparedness. Although such events are rare, when they do occur, they can cause mass casualties. In many models of mass casualty management, anesthesiology personnel are responsible for treating patients immediately on arrival at the hospital. We studied the extent of training offered to anesthesiology personnel in the use of WMD protective gear and patient management in United States (US) anesthesiology residency programs. Information was obtained via an online survey to all program directors and chair persons of anesthesiology programs. We polled all of the 135 US anesthesiology programs of which 90 (67%) responded. Only 37% had any form of training, and many of them did not repeat training after initial sessions. Twenty-eight percent of programs east of the Mississippi River reported some form of training whereas only 17% of programs west of it reported training available. The majority of anesthesia residency programs in the US that responded to our survey provided little or no training in the management of patients exposed to WMD.

IMPLICATIONS

In an attack involving weapons of mass destruction or toxic chemicals, anesthesiologists will provide care. Our survey of United States anesthesiology residency programs demonstrated that there is limited training of residents regarding the anesthetic management of patients injured by weapons of mass destruction. This has serious public health implications.

Changes of acetylcholinesterase activity after long-term exposure to sarin vapors in rats

In our study, rats were exposed to sarin vapors for 240 min at four different concentrations (0.30, 0.43, 0.58 and 0.82 microg/L) in a whole-body inhalation chamber. The acetylcholinesterase activity (AChE, EC 3.1.1.7) was measured in the whole blood, frontal cortex (FC), pontomedullar area (PM) and basal ganglia (BG). Convulsions and hypersalivation were observed in only one animal of the group exposed to the highest sarin concentration. The decrease in blood AChE activity was significant in all animals exposed to sarin vapors. The highest inhibition of AChE activity (61%) was determined in animals exposed to sarin vapors at a concentration of 0.82 microg/L. In the PM, AChE activity was decreased in all experimental groups, significantly only in the group exposed to sarin vapors at a concentration of 0.58 microg/L. Our results show that in long-term exposure to low concentrations of sarin, the significant decrease in AChE activity in the blood is followed by significant changes of AChE activity in the PM only. This part of the brain seems to be more sensitive than the FC or BG.

Organic Phosphorus Compounds—Nerve Agents

The organic phosphorous compounds (OPC) include both the military grade nerve agents and the organic phosphorous pesticides. The major mechanism of OPC toxicity is through inhibition of acetylcholinesterase in neuronal synapses leading to excess acetylcholine and overstimulation of target organs. Signs and symptoms depend on the affinity of the OPC for muscarinic versus nicotinic receptors, and are likely to include both. Muscarinic symptoms may include diarrhea, urination, bronchospasm, bronchorrhea, emesis, and salivation. Nicotinic symptoms such as paralysis and fasciculations may also occur. Central nervous system toxicity may include seizures, altered mental status, and apnea, and require prompt intervention. Treatment includes early airway and ventilatory support as well as antidotal therapy with atropine, pralidoxime, and diazepam. Goals of therapy include prevention and rapid treatment of hypoxia and seizures, as these are linked to patient outcome.

Decontamination

Decontamination is the removal or reduction of chemical, biologic, or radiologic agents from the patient's skin, mucosa, lungs, and gastrointestinal tract. Decontamination is an important step in decreasing the clinical effects of the agent on the patient, as well as protecting coworkers from exposure. For most agents and the vast majority of scenarios, the removal of clothing and a simple 5- to 6-minute shower with soap and water is sufficient to eliminate the risks to the patient and hospital staff. In rare circumstances, additional steps in decontamination including gastric lavage, broncho-alveolar lavage, surgical removal of wound foreign bodies, and administration of activated charcoal, polyethylene glycol electrolyte solution, and radioisotope binding agents, may be necessary.

Epidemiology of acute organophosphate poisoning in hospital emergency room patients

Acute organophosphate (OP) poisoning is a major health issue in developing countries. Organophosphate insecticides inhibit cholinesterase (ChE) enzymatic activity, thereby eliciting cholinergic signs and symptoms. Victims of OP poisoning require immediate hospital emergency room (ER) treatment to prevent a fatal outcome. We present an epidemiologic review of acute OP poisoning in hospital ER patients. Areas of interest include countries with acute OP poisoning, nature of exposure, gender and age of patients, clinical cholinergic features, ChE activity, and health outcome, including recovery rate, case fatality rate, and post-ER complications. The review comprises case reports, hospital surveys, and clinical studies on acute OP poisoning. More studies were conducted in developed than in developing countries. Suicidal and occupational OP poisoning in agricultural workers was prevalent in developing countries, whereas accidental OP poisoning was prevalent in developed countries. Healthcare workers in the ER were also affected by OP poisoning. Both males and females were affected. Children accounted for 35% of the OP-poisoned victims. Patients presented with a classic cholinergic syndrome and serum ChE depresssion, with a recovery rate above 90%. Neurologic impairment was the most frequent complication. Preventing environmental OP exposure and increasing the awareness of pesticide toxicity would reduce acute OP poisoning and protect human health.

Secondary Contamination of Emergency Department Personnel from o-Chlorobenzylidene Malononitrile Exposure, 2002

In a hazardous materials event in 2002, the unannounced presentation of 3 symptomatic, contaminated patients to an emergency department (ED) resulted in secondary contamination of 2 ED personnel who experienced skin, eye, and respiratory irritation. The material that caused these injuries was o-chlorobenzylidene malononitrile, a white powder with a peppery odor used largely as a tear gas and riot-control agent. Secondary contamination can cause adverse symptoms and injuries in ED personnel, further contaminate the ED, and potentially lead to costly ED closures and evacuations. To prevent secondary exposure, EDs can educate their staff about the potential for secondary contamination, implement a team approach for handling contaminated patients, establish decontamination protocols, ensure proper selection of and training in the use of personal protective equipment, and simulate drills for receiving contaminated patients.

Clinical review: Tokyo - protecting the health care worker during a chemical mass casualty event: an important issue of continuing relevance

Determine the effectiveness of decontamination, and perform thorough dry or wet decontamination, depending on the circumstances. Always remain cognizant of the fact that, even after decontamination has been completed, contamination may not have been completely eliminated. Perform periodic monitoring to determine whether secondary exposure has occurred in health care workers; if it appears that secondary exposure has occurred, then the PPE level must be increased and attempts must be made to identify and eliminate the source of the contamination. Finally, if the victims were exposed through ingestion, then consider the possibility that secondary exposure will occur during gastric lavage.

A Novel Method to Prevent Secondary Exposure of Medical and Rescue Personnel to Toxic Materials Under Biochemical Hazard Conditions Using Microwave Radar and Infrared Thermography

In order to prevent secondary exposure of medical personnel to toxic materials under biochemical hazard conditions, we performed a noncontact determination of exposure to toxic conditions via 1215-MHz microwave radar and thermography. A toxic condition was induced by intravenous administration of lipopolysaccharide (LPS) in rabbits. The exposure to LPS was determined by linear discriminant analysis using non-contact derived variables.

Lack of hospital preparedness for chemical terrorism in a major US city: 1996-2000

INTRODUCTION

The [US] Nunn-Lugar-Domenici Defense Against Weapons of Mass Destruction (WMD) Act (the WMD Act of 1996) heralded a new wave of spending by the federal government on counter-terrorism efforts. Between 1996 and 2000, the United States of America (US) federal government allocated large sums of funding to the States for bioterrorism preparedness. Distribution of these funds between institutions involved in first-responder care (e.g., fire and safety departments) and hospitals was uneven. It is unknown whether these additional funds had an impact on the level of hospital preparedness for managing mass casualties involving hazardous materials at the local level, including potential terrorist attacks with chemical agents.

OBJECTIVES

(1) To compare 1996 and 2000 measures of preparedness among hospitals of a major US metropolitan area for dealing with hazardous material casualties, including terrorism that involved the use of weapons of mass destruction; and (2) To provide guidance for the improvement of emergency preparedness and response in US hospitals.

METHODS

In July 1996 and again in July 2000,21 hospitals in one major US city were surveyed by questionnaire. A survey was used to assess the amounts of antidote stocks held available for treatment of casualties caused by toxic chemical agents and institutional response capabilities including the number of showers for decontaminating patients, the level of worker protection, and the number of staff trained to decontaminate patients.

RESULTS

Hospital preparedness for treating and decontaminating patients exposed to toxic chemical agents was inadequate in 1996 and in 2000. From 1996 to 2000, there was no statistically significant change in the lack of hospital preparedness for stocking of nerve agent and cyanide antidotes. Capacity for decontamination of patients, which included appropriate hazardous material infrastructure and trained staff, generally was unimproved from 1996 to 2000 with the exception of an increase of nearly 30% in hospitals with at least one decontamination shower facility.

CONCLUSION

Hospitals surveyed in this study were poorly prepared to manage chemical emergency incidents, including terrorism. This lack of hospital preparedness did not change significantly between 1996 and 2000 despite increased funds allocated to bioterrorism preparedness at the local level.

Practicality of performing medical procedures in chemical protective ensembles

OBJECTIVE

To determine whether certain life saving medical procedures can be successfully performed while wearing different levels of personal protective equipment (PPE), and whether these procedures can be performed in a clinically useful time frame.

METHODS

We assessed the capability of eight medical personnel to perform airway maintenance and antidote administration procedures on manikins, in all four described levels of PPE. The levels are: Level A--a fully encapsulated chemically resistant suit; Level B--a chemically resistant suit, gloves and boots with a full-faced positive pressure supplied air respirator; Level C--a chemically resistant splash suit, boots and gloves with an air-purifying positive or negative pressure respirator; Level D--a work uniform. Time in seconds to inflate the lungs of the manikin with bag-valve-mask, laryngeal mask airway (LMA) and endotracheal tube (ETT) were determined, as was the time to secure LMAs and ETTs with either tape or linen ties. Time to insert a cannula in a manikin was also determined.

RESULTS

There was a significant difference in time taken to perform procedures in differing levels of personal protective equipment (F21,72 = 1.75, P = 0.04). Significant differences were found in: time to lung inflation using an endotracheal tube (A vs. C mean difference and standard error 75.6 +/- 23.9 s, P = 0.03; A vs. D mean difference and standard error 78.6 +/- 23.9 s, P = 0.03); time to insert a cannula (A vs. D mean difference and standard error 63.6 +/- 11.1 s, P < 0.001; C vs. D mean difference and standard error 40.0 +/- 11.1 s, P = 0.01).

CONCLUSIONS

A significantly greater time to complete procedures was documented in Level A PPE (fully encapsulated suits) compared with Levels C and D. There was however, no significant difference in times between Level B and Level C. The common practice of equipping hospital and medical staff with only Level C protection should be re-evaluated.

Application of a cuirass and institution of biphasic extra-thoracic ventilation by gear-protected physicians

OBJECTIVES

To evaluate the speed by which cuirass application, followed by biphasic extra-thoracic ventilation, can be instituted by full anti-chemical protective gear-wearing physicians.

MATERIALS AND METHODS

Ten physicians of variable subspecialties applied a cuirass on an adult volunteer and instituted biphasic extra-thoracic ventilation, using the RTX respirator (Medivent, London, UK). Endotracheal (ET) intubation and manual ventilation of a mannequin and its ventilation was comparatively assessed. Performances were conducted in a prospective, crossover, randomized manner. Times to successful applications as well as failure rates were recorded.

RESULTS

Cuirass application was performed more rapidly (102 +/- 9 s, 177 +/- 31 s, respectively, P <.01) and with a slightly lower failure rate than ET intubation.

CONCLUSIONS

Physicians wearing full anti-chemical protective gear applied the cuirass and instituted biphasic extra-thoracic ventilation faster than ET intubation and manual positive pressure ventilation. Extra-thoracic ventilation should be further evaluated as an option for emergent respiratory support during toxic mass casualty events.

Secondary contamination in organophosphate poisoning: analysis of an incident

BACKGROUND

Acute organophosphate poisoning is rare in the UK, and the risks to attending staff are seldom appreciated.

STUDY DESIGN

Report of an incident.

RESULTS

In May 2001, a 45-year-old man attempted suicide by drinking organophosphate insecticide, and was brought to an urban general hospital in a collapsed state. Twenty-five hospital workers and paramedics sought medical advice after coming into contact with the poisoned patient, of whom ten complained of symptoms related to toxin exposure. Provision of emergency services by the hospital was compromised, and the emergency department was closed until the area was decontaminated and staffing levels could be restored.

DISCUSSION

Ingestion of OP compounds can present a significant risk to health professionals as well as patients. Problems with the management of this patient included late recognition of the need for decontamination, large numbers of non-essential staff coming into contact with the patient, and the difficulty of carrying out medical procedures while wearing protective equipment. Decontamination should always be considered early, and the possibility of an ingested poison being vomited and causing a chemical spill should not be overlooked.

Toxicology in the critically ill patient

Intoxications present in many forms including: known drug overdose or toxic exposure, illicit drug use, suicide attempt, accidental exposure, and chemical or biological terrorism. A high index of suspicion and familiarity with toxidromes can lead to early diagnosis and intervention in critically ill, poisoned patients. Despite a paucity of evidence-based information on the management of intoxicated patients, a rational and systematic approach can be life saving.

Protective equipment for health care facility decontamination personnel: regulations, risks, and recommendations

After recent terrorist attacks, new attention has been focused on health care facility decontamination practices. This article reviews core issues related to the selection of appropriate personal protective equipment for health care facility decontamination personnel, with an emphasis on respiratory protection. Existing federal regulations focus primarily on scene response and not on issues specific to health care facility decontamination practices. Review of existing databases, relevant published literature, and individual case reports reveal some provider health risks, especially when the exposure involves organophosphate agents. However, reported risks from secondary exposure to contaminated patients at health care facilities are low. These risks should be adequately addressed with Level C personal protective equipment, including air-purifying respirator technologies, unless the facility determines that specific local threats require increased levels of protection.

Resuscitative challenges in nerve agent poisoning

The threat of weapons of mass destruction such as nerve agents has become real since last year. The medical community has established protocols for the rapid evacuation and decontamination of affected civilians. However, protocols for resuscitative measures or acute perioperative care in cases of life-saving surgical interventions in toxic-traumatized casualties are still lacking. The database concerning the effects of nerve agent poisoning in humans is limited, and is largely based on reports of unintentional exposures to pesticide organophosphate poisoning and similar chemical substances. In this review, we summarize the knowledge on the possible pharmacological interactions between nerve agents and acute care.

Establishing and training health care facility decontamination teams

Recent terrorist events, changes in Joint Commission on Accreditation of Healthcare Organizations requirements, and availability of grant funding have focused health care facility attention on emergency preparedness. Health care facilities have historically been underprepared for contaminated patients presenting to their facilities. These incidents must be properly managed to reduce the health risks to the victims, providers, and facility. A properly equipped and well-trained health care facility team is a prerequisite for rapid and effective decontamination response. This article reviews Occupational Safety and Health Administration (OSHA) training requirements for personnel involved with decontamination responses, as well as issues of team selection and training. Sample OSHA operations-level training curricula tailored to the health care environment are outlined. Initial and ongoing didactic and practical training can be implemented by the health care facility to ensure effective response when contaminated patients arrive seeking emergency medical care.

Management issues surrounding the United Kingdom health services' ability to deal effectively with major incidents involving bioterrorism

AIM

This paper aims to explore the management structures and issues surrounding the United Kingdom (UK) health services' preparedness and ability to effectively deal with major incidents involving bioterrorism.

BACKGROUND

Recent reports and expert opinion have suggested that the health service response to terrorist incidents involving weapons of mass destruction are insufficient and ill-prepared.

KEY ISSUES

Lack of clear guidance and parity across the UK, poor targeting of information, inadequate and insufficient equipment, under-resourcing, and unsatisfactory training are key factors that contribute to a worrying state of frontline unpreparedness.

CONCLUSIONS

Health service managers need to capitalize on the Government's current concern about the threat of a bioterrorist attack and ensure that their departments are sufficiently equipped, and that their personnel are adequately educated and trained, to deal with any such incident. Better guidance needs to be produced and distributed to front line healthcare workers.

New challenges for public health care: biological and chemical weapons awareness, surveillance, and response

Recent events in the United States have demonstrated a critical need for recognizing nurses and emergency health care providers as important elements of the nation's first line of defense and response against terrorist attacks involving biological, chemical, or radiological weapons. The anthrax letter attacks of September/October 2001 demonstrate the importance of vigilance and attention to detail while interviewing and attending patients and when entering, reviewing, and cataloging patient records. Nursing professionals, emergency care responders, and physicians can perform a crucial role in our first-line defense against terrorism by detecting and reporting unusual or anomalous illness(es) consistent with possible exposure to biological or chemical agents. Nursing professionals should become more familiar with the etiology and clinical symptoms of biological agents of greatest current concern (smallpox, anthrax, tularemia, plague) and be alert for potentially anomalous or unfamiliar combinations of symptoms that could point to unwitting exposure to biological toxins, toxic chemicals, or cryptic radiological agents. Public health surveillance systems must be developed that encourage and facilitate the rapid reporting and follow-up investigation of suspect illnesses and potential disease outbreaks that will ensure early identification and response for covert attacks involving biological, chemical, or radiological weapons.