Adult toxicology in critical care: part I: general approach to the intoxicated patient

Anticoagulant Overdose With Paradoxical Thrombotic Risk

We report a case of an unusual polypharmacy overdose including warfarin in a patient with a metallic heart valve, complicated by the history that he had ceased taking anticoagulation in the preceding few months, that placed him in an initial prothrombotic phase during his presentation. Our case highlights the importance of elucidating all relevant clinical details in a polypharmacy overdose, as clearly and rapidly as feasible, to enable appropriate management.

Mad honey (wild honey) poisoning: clinical case series from Nepal

Introduction

Mad honey is commonly used for hypertension, and coronary artery disease, and as a sexual stimulant. Patients with mad honey poisoning present with dizziness, nausea, syncope, blurred vision, bradycardia, and hypotension with ECG findings of sinus bradycardia, complete AV block, and ST elevation.

Case discussion

Here, the authors report five cases admitted to our tertiary care center following the consumption of mad honey. The amount of ingestion of honey varies from 1 to 2 teaspoons (~10-20 ml). Most of the cases presented with chief complaints of nausea, dizziness, and vomiting, and all the cases had hypotension and bradycardia. Two cases were admitted to the ward and three of them were admitted to the ICU for further management. They were managed with intravenous fluid, injection atropine along with adjunctive vasopressor and oxygen whenever necessary.

Discussion

Mad honey contains grayanotoxin extracted from the nectar of Rhododendron species. This honey contains grayanotoxin, which binds to sodium channels in its open state causing hyperpolarization of the sodium channel predominantly causing gastrointestinal, neurological, and respiratory symptoms. Intravenous fluids and injection atropine are the mainstays of management in an ICU setup. Some also may require vasopressors.

Conclusion

Mad honey poisoning is rare, and limited cases have been reported in Nepal. Physicians should consider mad honey poisoning in cases with ingestion history and clinical symptoms, as it may be a clinical diagnosis due to limited lab tests for grayanotoxin intoxication. Supportive management still forms the cornerstone for its management after diagnosis.

Risk factors for the need for advanced care among prescription and over-the-counter drug overdose patients

Aim

Prescription drug and over-the-counter (OTC) drug overdose is a major problem in emergency departments in Japan, and some need advanced care which is more than observation. We aimed to identify the prehospital risk factors for the need of advanced care among overdose patients.

Methods

This was a single-center retrospective cohort study. We included overdoses patients of prescription drugs or OTC drugs, who admitted to our hospital between 2016 and 2021. We grouped them into advanced care and non-advanced care. The main outcome was the need for advanced care. We performed a multiple logistic regression analysis, calculated the PAV score (Paracetamol use, Alcohol use, abnormal Vital signs on scene) and performed a receiver operating characteristic (ROC) analysis.

Results

There were 229 subjects. The logistic regression analysis revealed that alcohol, paracetamol, and the abnormal vital signs on scene were associated with advanced care (alcohol-odds ratio [OR]: 2.95; 95% confidence interval [CI]: 1.29-6.75; paracetamol-OR: 5.47; 95% CI: 2.18-13.71; abnormal vital signs-OR: 4.61, 95% CI: 2.07-10.27). The rate of advanced care in the high PAV score (2 and 3) group was statistically higher than that in the low PAV score (0-1) group (p = 0.04). Area under the ROC curve of the PAV score was 0.72 (95% CI, 0.65-0.80).

Conclusion

Alcohol, paracetamol use and abnormal vital signs on scene might be risk factors for advanced care among prescription drugs or OTC drugs overdose patients, and the PAV score may predict the need for advanced care.

Toxicological Emergencies

Poisoning, drug overdose, and adverse drug effects continue to be a common encounter, especially in the intensive care unit (ICU). Patients are often critically ill or have a potential to rapidly deteriorate and warrant ICU admission. Adults suffering from overdoses rarely give a complete and accurate description of the quantity or type of medications ingested. In most adult cases, multiple substances are involved. A tentative diagnosis in most overdose and poisoning cases can be made by physical examination and simple laboratory tests (electrolyte panel, creatinine, serum osmolarity, urinalysis, etc). Supportive care, with particular attention to airway management, oxygenation, and circulation, is the mainstay of treatment. Basic treatment principles include limiting the amount of toxin absorbed, enhancing the elimination of ingested toxin, and preventing the conversion of non-toxic compounds to toxic metabolites. Drugs or poisons, where specific antidotes or effective therapies exist (especially acetaminophen, salicylates, methanol, ethylene glycol, and digitalis), should be aggressively sought and treated after initial stabilization has been accomplished. For those drugs or poisons where specific quantitative tests are available, levels should be obtained before treatment and may be repeated as clinically indicated.

Fluid Stewardship of Maintenance Intravenous Fluids

Despite the frequent use of maintenance intravenous fluids (mIVF) in critically ill patients, limited guidance is available. Notably, fluid overload secondary to mIVF mismanagement is associated with significant adverse patient outcomes. The Four Rights (right drug, right dose, right duration, right patient) construct of fluid stewardship has been proposed for the safe evaluation and use of fluids. The purpose of this evidence-based review is to offer practical insights for the clinician regarding mIVF selection, dosing, and duration in line with the Four Rights of Fluid Stewardship.

Comparison between various scoring systems in predicting the need for intensive care unit admission of acute pesticide-poisoned patients

The decision of intensive care unit (ICU) admission in acute pesticide poisoning is often challenging, especially in developing countries with limited resources. This study was conducted to compare the efficacy of the Acute Physiology and Chronic Health Evaluation II (APACHE II), Modified Early Warning Score (MEWS), and Poisoning Severity Score (PSS) in predicting ICU admission and mortality of acute pesticide-poisoned patients. This prospective cohort study included all patients admitted to Tanta University Poison Control Center with acute pesticide poisoning from the start of March 2018 to the end of March 2019. Patient data, including demographic and toxicological data, clinical examination, laboratory investigation, and score values, were collected on admission. Out of 337 acute pesticide-poisoned patients, 30.5% were admitted to the ICU, including those poisoned with aluminum phosphide (ALP) (81.5%) and organophosphates (OP) (18.5%). Most non-survivors (86.6%) were ALP poisoning. The PSS had the best discriminatory power in predicting ICU admission and mortality, followed by APACHE II and MEWS. However, no significant difference in predicting ICU admission of OP-poisoned patients was detected between the scores. Additionally, no significant difference in mortality prediction of ALP-poisoned patients was found between the PSS and APACHE II. The PSS, APACHE II, and MEWS are good discriminators for outcome prediction of acute pesticide poisoning on admission. Although the PSS showed the best performance, MEWS was simpler, more feasible, and practicable in predicting ICU admission of OP-poisoned patients. Moreover, the APACHE II has better sensitivity for mortality prediction of ALP-poisoned patients.

A Supramolecular Antidote to Macromolecular Toxins Prepared through Coassembly of Macrocyclic Amphiphiles

Poisoning is a leading cause of admission to medical emergency departments and intensive care units. Supramolecular detoxification, which involves injecting supramolecular receptors that bind with toxins to suppress their biological activity, is an emerging strategy for poisoning treatment; it has few requirements and a broad application scope. However, it is still a formidable challenge to design supramolecular therapeutic materials as an antidote to macromolecular toxins, because the large size, flexible conformation, and presence of multiple and diverse binding sites of biomacromolecules hinder their recognition. Herein, a supramolecular antidote to macromolecular toxins is developed through the coassembly of macrocyclic amphiphiles, relying on heteromultivalent recognition between the coassembled components and toxic macromolecules. The coassembly of amphiphilic cyclodextrin and calixarene strongly and selectively captures melittin, a toxin studied herein; this imparts various therapeutic effects such as inhibiting the interactions of melittin with cell membranes, alleviating melittin cytotoxicity and hemolytic toxicity, reducing the mortality rate of melittin-poisoned mice, and mitigating damage to major organs. The use of the proposed antidote overcomes the limitation of supramolecular detoxification applicability to only small-molecular toxins. The antidote can also detoxify other macromolecular toxins as long as selective and strong binding is achieved because of the coassembling tunability.

Suvorexant Poisoning in a Patient With Cirrhosis and Renal Failure

Suvorexant is a novel hypnotic that acts as an orexin-1 receptor and orexin-2 receptor antagonist. Owing to its safety and tolerability, suvorexant has recently become widely used. However, little is known about the presentation of suvorexant poisoning. Here, we describe an 83-year-old man with cirrhosis and renal failure, who had taken 270 mg of suvorexant at the same time. After the overdose, he did not develop any symptoms other than prolonged drowsiness. He was successfully treated with supportive therapy alone. This is the first report describing suvorexant poisoning. Further reports should be accumulated to determine whether patients with suvorexant poisoning present with mild symptoms without intensive treatment.

Risk factors for prolonged intensive care unit and hospital stay among patients with acute drug overdose in Japan

Aim

Hospital selection for patients with drug overdose (DOD) is a critical issue. In Tokyo, the 50‐tablet rule has been widely utilized by paramedics for triaging patients with DOD given that it shortens the triage time. However, studies have not investigated the utility of such a rule in local cities. The present study aimed to identify prognostic pre‐ and in‐hospital factors among patients with DOD and determine whether the 50‐tablet rule benefits local cities.

Methods

Clinical records of patients with DOD admitted at the University of Tsukuba Hospital (Tsukuba, Japan) between 2013 and 2017 were retrospectively reviewed.

Results

A total of 93 patients with DOD were enrolled in this study. Multivariate analysis showed that creatine kinase and C‐reactive protein values and the total number of ingested pills were in‐hospital risk factors that significantly prolonged intensive care unit (ICU) and hospital stay. Moreover, Glasgow Coma Scale score on admission and the total number of ingested pills were identified as significant pre‐hospital risk factors for prolonged ICU and hospital stay. Setting the total number of ingested pills to 50 tablets did not significantly influence ICU and hospital stay.

Conclusion

The total number of ingested pills and creatine kinase and C‐reactive protein values were identified as predictive factors for prolonged ICU and hospital stay in patients with DOD after admission. Moreover, pre‐hospital risk factors included Glasgow Coma Scale score and the total number of ingested pills. However, the 50‐tablet rule was determined to be a poor cut‐off value for patients with DOD. We presented a subset of our findings at the 46th annual meeting of the Japanese Society for Acute Medicine (Yokohama, Japan) on 20 November 2018.

Diagnosis of acute intoxications in critically ill patients: focus on biomarkers - part 1: epidemiology, methodology and general overview

Acute intoxications account for a significant proportion of the patient population in intensive care units and sedative medications, ethanol, illicit drugs, inhalable poisons and mixed intoxications are the most common causes. The aim of this article is to describe biomarkers for screening and diagnosis of acute intoxications in critically ill patients. For this purpose, a survey of the relevant literature was conducted, and guidelines, case reports, expert assessments, and scientific publications were reviewed. In critical care, it should always be attempted to identify and quantify the poison or toxin with the assistance of enzyme immunoassay (EIA), chromatography, and mass spectrometry techniques and this section is critically appraised in this publication. The principles for anion gap, osmol gap and lactate gap and their usage in intoxications is shown. Basic rules in test methodology and pre-analytics are reviewed. Biomarkers in general are presented in part one and biomarkers for specific intoxications including ethanol, paracetamol, cardiovascular drugs and many others are presented in part two of these publications.

A Review on Ingested Cyanide: Risks, Clinical Presentation, Diagnostics, and Treatment Challenges

Cyanide, a metabolic poison, is a rising chemial threat and ingestion is the most common route of exposure. Terrorist organizations have threatened to attack the USA and international food and water supplies. The toxicokinetics and toxicodynamics of oral cyanide are unique, resulting in high-dose exposures, severe symptoms, and slower onset of symptoms. There are no FDA-approved therapies tested for oral cyanide ingestions and no approved intramuscular or oral therapies, which would be valuable in mass casualty settings. The aim of this review is to evaluate the risks of oral cyanide and its unique toxicokinetics, as well as address the lack of available rapid diagnostics and treatments for mass casualty events. We will also review current strategies for developing new therapies. A review of the literature using the PRISMA checklist detected 7284 articles, screened 1091, and included 59 articles or other reports. Articles referenced in this review were specific to risk, clinical presentation, diagnostics, current treatments, and developing therapies. Current diagnostics of cyanide exposure can take hours or days, which can delay treatment. Moreover, current therapies for cyanide poisoning are administered intravenously and are not specifically tested for oral exposures, which can result in higher cyanide doses and unique toxicodynamics. New therapies developed for oral cyanide exposures that are easily delivered, safe, and can be administered quickly by first responders in a mass casualty event are needed. Current research is aimed at identifying an antidote that is safe, effective, easy to administer, and has a rapid onset of action.

Identifying Life-Threatening Admissions for Drug Dependence or Abuse (ILIADDA): Derivation and Validation of a Model

Given that drug abuse and dependence are common reasons for hospitalization, we aimed to derive and validate a model allowing early identification of life-threatening hospital admissions for drug dependence or abuse. Using the French National Hospital Discharge Data Base, we extracted 66,101 acute inpatient stays for substance abuse, dependence, mental disorders or poisoning associated with medicines or illicit drugs intake, recorded between January 1st, 2009 and December 31st, 2014. We split our study cohort at the center level to create a derivation cohort and a validation cohort. We developed a multivariate logistic model including patient's age, sex, entrance mode and diagnosis as predictors of a composite primary outcome of in-hospital death or ICU admission. A total of 2,747 (4.2%) patients died or were admitted to ICU. The risk of death or ICU admission was mainly associated with the consumption of opioids, followed by cocaine and other narcotics. Particularly, methadone poisoning was associated with a substantial risk (OR: 35.70, 95% CI [26.94-47.32], P < 0.001). In the validation cohort, our model achieved good predictive properties in terms of calibration and discrimination (c-statistic: 0.847). This allows an accurate identification of life-threatening admissions in drug users to support an early and appropriate management.

Flumazenil, naloxone and the 'coma cocktail'

Flumazenil and naloxone are considered to be pharmacologically ideal antidotes. By competitive binding at the molecular target receptors, they are highly specific antagonists of two important drug classes, the benzodiazepines and opioids, respectively. Both antidotes enjoy rapid onset and short duration after parenteral administration, are easily titrated and are essentially devoid of agonist effects. Yet only naloxone is widely used as a component of the 'coma cocktail', a sequence of empirical treatments to correct altered mental status, while experts discourage the use of flumazenil for such patients. This review contrasts the history, indications, published evidence and novel applications for each antidote in order to explain this disparity in the clinical use of these 'ideal' antidotes.

Psychiatric and medical management of marijuana intoxication in the emergency department

We use a case report to describe the acute psychiatric and medical management of marijuana intoxication in the emergency setting. A 34-year-old woman presented with erratic, disruptive behavior and psychotic symptoms after recreational ingestion of edible cannabis. She was also found to have mild hypokalemia and QT interval prolongation. Psychiatric management of cannabis psychosis involves symptomatic treatment and maintenance of safety during detoxification. Acute medical complications of marijuana use are primarily cardiovascular and respiratory in nature; electrolyte and electrocardiogram monitoring is indicated. This patient's psychosis, hypokalemia and prolonged QTc interval resolved over two days with supportive treatment and minimal intervention in the emergency department. Patients with cannabis psychosis are at risk for further psychotic sequelae. Emergency providers may reduce this risk through appropriate diagnosis, acute treatment, and referral for outpatient care.

An Atypical Case of Methemoglobinemia due to Self-Administered Benzocaine

Acquired methemoglobinemia is an uncommon hemoglobinopathy that results from exposure to oxidizing agents, such as chemicals or medications. Although, as reported in the adult population, it happens most often due to prescribed medication or procedural anesthesia and not due to easily accessed over-the-counter medications, the authors will describe an otherwise healthy male adult with no known medical history and no prescribed medications, who presented to the emergency department reporting generalized weakness, shortness of breath, headache, dizziness, and pale gray skin. In addition, the patient reported that he also had a severe toothache for several days, which he had been self-treating with an over-the-counter oral benzocaine gel. Ultimately, the diagnosis of methemoglobinemia was made by clinical history, physical examination, and the appearance of chocolate-colored blood and arterial blood gas (ABG) with cooximetry. After 2 mg/kg of intravenous methylene blue was administered, the patient had complete resolution of all signs and symptoms. This case illustrates that emergency physicians should be keenly aware of the potential of toxic hemoglobinopathy secondary to over-the-counter, nonprescribed medications. Discussion with patients regarding the dangers of inappropriate use of these medicines is imperative, as such warnings are typically not evident on product labels.

Clinical and biochemical analysis of acute paint thinner intoxication in adults: a retrospective descriptive study

CONTEXT

Paint thinner contains a mixture of various aromatic hydrocarbons. A few studies have reported biochemical abnormalities and clinical symptoms of paint thinner intoxication among adult patients.

OBJECTIVE

We aimed to design a retrospective descriptive study to evaluate clinical and laboratory biochemistry abnormalities due to paint thinner intoxication among adult patients.

METHODS

Data were obtained by using questionnaires from paint thinner-intoxicated patients recruited at the Loghman-Hakim General Teaching Hospital Poison Center.

RESULTS

Clinical and paraclinical data from a total of 37 patients, 24 males (64.86%) and 13 females (35.14%) with the mean age of 34.35 ± 14.15 years and mode of 22 years, was obtained and analyzed. Patients' ages ranged between 15 and 70 years. The estimated mean consumed dose was 246.70 ± 390.72 ml with a mode of 60 ml (range of 1-1500 ml). Nausea, vomiting, asthma, sore throat, stomach ache, drowsiness, dizziness, agitation, cough and diarrhea were the most frequent clinical features, respectively. Reported tissue damage biomarkers were alkaline phosphatase (ALP, 233.84 ± 122.06) and lactate dehydrogenase enzymes (LDH, 749.33 ± 471.03 IU/l). They reflected development of liver and pulmonary toxicities. Arterial blood gas (ABG) showed acidosis without hypoxia in adult paint thinner-intoxicated patients.

DISCUSSION AND CONCLUSION

Focusing on biochemical abnormalities and clinical toxicity symptoms is essential for screening organs in paint thinner toxicity. In addition, they provide good information for physicians/clinical toxicologists to perform appropriate conservative treatments in adult paint thinner-intoxicated patients.

Availability of treatment resources for the management of acute toxic exposures and poisonings in emergency departments among various types of hospitals in Palestine: a cross-sectional study

BACKGROUND

Poisoning exposures continue to be a significant cause of morbidity and mortality worldwide. The lack of facilities, treatment resources, and antidotes in hospitals may affect the treatments provided and outcomes. This study aimed to determine the availability of gastrointestinal (GI) decontamination, stabilisation, elimination enhancement resources, and antidotes for the management of acute toxic exposures and poisonings in emergency departments (EDs) among various types of governmental and private hospitals in Palestine.

METHODS

A cross-sectional study using semi-structured questionnaire was performed. Data were collected based on hospital resources; GI decontamination, stabilisation, elimination enhancement resources and antidotes from Palestinian hospitals.

RESULTS

Eighteen hospitals (94.7%) have responded. Among them, paracetamol poisoning was the most frequently reported cases by EDs (mean frequency score = 7.6 ± 2.1), followed by bee stings (mean = 6.9 ± 2.7) and organophosphate poisoning (mean = 6.7 ± 2.7). The availabilities of most resources related to GI decontamination items varied substantially with hospital type, but these differences were not statistical significant. The availability of stabilisation resources was not significantly different between hospitals types. For the availability of techniques used to enhance the elimination of toxic substances, there were variations between the hospitals types. However, these differences were not statistical significant, except for haemodialysis (p = 0.003) which was more available in governmental hospitals. For the availability of antidotes, none of the hospitals had sufficient stock of all antidotes listed. In relation to hospital type, there was variability in the availability of antidotes, but this did not reach statistical significance, except for deferoxamine (p < 0.001), which was available in all governmental hospitals but none of the private hospitals.

CONCLUSIONS

The availability of treatment resources and antidotes in Palestinian hospitals was not adequate except for stabilisation resources. The availability of such resources acts as a marker for the level of readiness of hospital EDs in Palestine for the management of acute toxic exposure and poisoning. The implementation of a minimum list of antidotes and treatment resources would be useful to increase the level of resources. Coordination between Palestinian poison control and drug information centre and hospitals is also important.

Characteristics of patients admitted to the intensive care unit following self-poisoning and their impact on resource utilisation

BACKGROUND

Self-poisoning accounts for up to 10 % of hospital admissions, some of whom require admission to ICU. Few studies have looked at the epidemiology of these patients in an Irish setting.

AIMS

To quantify the proportion of ICU admissions attributable to self-poisoning, to examine the characteristics and outcome of these patients, and to assess their ICU resource utilisation.

METHODS

Retrospective review of ICU admissions from 2006 to 2010. Data were collected on patient age, sex, admission diagnosis, substances involved, APACHE II score, length of stay, organ support, and outcome.

RESULTS

There were 80 admissions to ICU following self-poisoning accounting for 3.8 % of ICU admissions and 13 % of all hospital admissions for self-poisoning. M:F ratio was 0.9:1. Mean age 35 (range 16-75), APACHE II score 14 (2-36). Commonest substances involved were benzodiazepines, opioids, tricycle antidepressants. Median ICU stay was 2 days (IQR 0.96-4.5). 84 % of patients were ventilated, 27.5 % required inotropic support, 14 % renal replacement therapy. When opioids were involved requirement for inotropes and CRRT were higher. ICU mortality was 6.3 %. These patients consumed 280 bed days.

CONCLUSION

Self-poisoning accounted for 3.8 % of ICU admissions. Patients tend to require a short period of ventilation, with a minority requiring additional organ support. The cost of ICU care is calculated based on previously published methodology to be <euro>7,717 per patient. Extrapolated nationally the annual cost for ICU care for self-poisoning is estimated to be in the order of <euro>5 m.

Availability of decontamination, elimination enhancement, and stabilization resources for the management of acute toxic exposures and poisonings in emergency departments in Malaysia

Acute poisoning is a common medical emergency in Malaysia. Life can be saved if the patient is diagnosed properly and receives the appropriate treatment such as gastrointestinal decontamination techniques and resources to increase poison elimination according to clinical guidelines at a reasonable time. The aims of this study were to determine the availability of decontamination, elimination enhancement, and stabilization resources for the management of acute toxic exposures and poisonings in accident and emergency departments in Malaysia, and to compare the availability of such facilities among various types of hospitals. A comparative, descriptive cross-sectional study was conducted using a structured questionnaire. Seventy-four (58.3%) out of the targeted 127 hospitals replied and completed the questionnaire. The availabilities of most items related to stabilization resources were far better in general hospitals compared to district hospitals with specialists and district hospitals without specialists. These items were mechanical ventilators (p = 0.011), non-invasive positive pressure ventilators (0.024), pacemakers (p = 0.019), and transcutaneous cardiac pacing (p < 0.001). The availability of decontamination resources varied substantially with hospital type. Nevertheless, these differences did not reach statistical significance in any of the cases, whereas sodium sulphate, sorbitol, and polyethylene glycol were almost never available. The availabilities of most items related to elimination enhancement resources were far better in general hospitals and district hospitals with specialists compared to district hospitals without specialists. These items were haemodialysis (p = 0.046), haemoperfusion (p = 0.002), haemofiltration (p = 0.002), acid diuresis (p = 0.04), peritoneal dialysis (p < 0.001), and exchange transfusion (p < 0.001). Most Malaysian hospitals have certain important immediate interventions such as gastrointestinal decontamination techniques and resources to increase poison elimination. The availabilities of most facilities were far better in the general hospitals. Coordination between the National Poison Centre in Malaysia and hospitals should be established regarding the emergency facilities for effective management of poisoning cases in each hospital in order to direct the poisoned patients to the hospital where the appropriate management resources is available.

Toxicology today: what you need to know now

Clinicians are frequently confronted with toxicological emergencies and challenged with the task of correctly identifying the possible agents involved and providing appropriate treatments. In this review article, we describe the epidemiology of overdoses, provide a practical approach to the recognition and diagnosis of classic toxidromes, and discuss the initial management strategies that should be considered in all overdoses. In addition, we evaluate some of the most common agents involved in poisonings and present their respective treatments. Recognition of toxidromes with knowledge of indications for antidotes and their limitations for treating overdoses is crucial for the acute care of poisoned patients.

Glasgow Coma Scale in acute poisonings before and after use of antidote in patients with history of use of psychotropic agents

INTRODUCTION

Data on emergency interventions in poisonings are scarce. Objective To determine the effectiveness of antidote therapy in acute poisoning-related emergency medical services (EMS) interventions.

METHODS

A prospective observational study included all poisoning-related intervention cases over 3 years (1999-2001) in the Celje region, Slovenia, covering 125,000 inhabitants. Data were recorded on an EMS form.

RESULTS

Psychoactive agents were present in 56.5% out of 244 poisoning-related EMS interventions. Prescription drugs were a cause of intoxication in 93 (39.2%) cases alone or in combination with alcohol or illegal drugs. More than one fifth of poisonings were due to the use of illegal drugs in 52 (21.9%) cases, 43 (18.1%) out of them heroin related. At the time of EMS arrival, more patients who ingested illegal drugs were in coma or comatose than the rest. 24 (45.3%) vs. 32 (17.3%) of poisoned patients were in coma (p < 0.001). Glasgow Coma Scale (GCS) at the first contact was lower in patients who ingested illegal drugs than in the remaining patients (9.0 vs. 11.6, p = 0.001). In 23.2% of the cases, an antidote was administered. In 29 (12.2%) naloxone and in 16 (6.7%) flumazenil was administered. Mean GCS after intervention was higher in all cases but significantly higher in illegal drug cases, 13.4 vs. 12.2 (p = 0.001), with a mean positive change in GCS of 4.5 vs. 0.6 (p < 0.001). In illegal drug users, mean change after antidote administration was 8.2 vs. 0.5 without antidote administration (p < 0.001).

CONCLUSION

High rate of successful antidote use during the intervention indicated the importance of good EMS protocols and the presence of a skilled doctor in the EMS team.

Over 8 years experience on severe acute poisoning requiring intensive care in Hong Kong, China

In order to obtain up-to-date information on the pattern of severe acute poisoning and the characteristics and outcomes of these patients, 265 consecutive patients admitted to an intensive care unit in Hong Kong for acute poisoning from January 2000 to May 2008 were studied retrospectively. Benzodiazepine (25.3%), alcohol (23%), tricyclic antidepressant (17.4%), and carbon monoxide (15.1%) were the four commonest poisons encountered. Impaired consciousness was common and intubation was required in 67.9% of admissions, with a median duration of mechanical ventilation of less than 1 day. The overall mortality was 3.0%. Among the 257 survivors, the median lengths of stay in the intensive care unit and acute hospital (excluding days spent in psychiatric ward and convalescent hospital) were less than 1 day and 3 days, respectively. Factors associated with a longer length of stay included age of 65 or older, presence of comorbidity, Acute Physiology and Chronic Health Evaluation II score of 25 or greater, and development of shock, rhabdomyolysis, and aspiration pneumonia, while alcohol intoxication was associated with a shorter stay. This is the largest study of its kind in the Chinese population and provided information on the pattern of severe acute poisoning requiring intensive care admission and the outcomes of the patients concerned.

Reliability of anion gap calculated from data obtained using a blood gas analyzer: is the probability of error predictable?

BACKGROUND

Anion gap (AG) is a useful index for assessing the clinical condition of critically ill patients especially in intoxication. Recently, AG can be obtained easily using a blood gas analyzer (BGA); however, its reliability requires validation.

METHODS

We enrolled patients who simultaneously underwent blood gas analysis and blood test in the central hospital laboratory and patients who visited the emergency department of our hospital from January 1, 2004, to December 31, 2007. The deviation of AG calculated using the BGA and that calculated by the central hospital laboratory were extracted. From the data obtained using the BGA, the independent risk factor causing a significant error in AG was statistically analyzed.

RESULTS

A total of 2922 patients were enrolled, of which 339 were defined as the significant error group. Male sex, abnormal Hco(3)(-), abnormal lactate, abnormal K, abnormal Cl, and abnormal Na were the independent risk factors producing the significant error. The results indicate that regardless of whether the original electrolyte data of the patients are abnormal, when the electrolyte measurement results obtained using the BGA are abnormal, the calculated AG might show a significant error. In addition, the fact that lactate was determined as a risk factor indicates that AG might be more useful in patients who have intoxication than in those under an unstable state in terms of vital signs.

CONCLUSION

When risk factors are present, the medical condition of a patient should be reevaluated by comparing results without heavily relying on the AG obtained by a BGA.

The Functional Outcome and Recovery of Patients Admitted to an Intensive Care Unit following Drug Overdose: A Follow-Up Study

Patients who have overdosed on drugs commonly present to emergency departments, with only the most severe cases requiring intensive care unit (ICU) admission. Such patients typically survive hospitalisation. We studied their longer term functional outcomes and recovery patterns which have not been well described.

All patients admitted to the 18-bed ICU of a university-affiliated teaching hospital following drug overdoses between 1 January 2004 and 31 December 2006 were identified. With ethical approval, we evaluated the functional outcome and recovery patterns of the surviving patients 31 months after presentation, by telephone or personal interview. These were recorded as Glasgow outcome score, Karnofsky performance index and present work status.

During the three years studied, 43 patients were identified as being admitted to our ICU because of an overdose. The average age was 34 years, 72% were male and the mean APACHE II score was 16.7. Of these, 32 were discharged from hospital alive. Follow-up data was attained on all of them. At a median of 31 months follow-up, a further eight had died. Of the 24 surviving there were 13 unemployed, seven employed and four in custody. The median Glasgow outcome score of survivors was 4.5, their Karnofsky score 80.

Admission to ICU for treatment of overdose is associated with a very high risk of death in both the short- and long-term. While excellent functional recovery is achievable, 16% of survivors were held in custody and 54% unemployed.

Aetiological and demographical characteristics of acute poisoning in the Celje region, Slovenia

BACKGROUND

Data on emergency treatment of poisonings are scarce.

OBJECTIVE

To determine the annual rate of poisoning-related emergency medical services (EMS) interventions and to determine the aetiology and demographic characteristics of poisoning cases.

METHODS

A prospective observational study included all poisoning-related intervention cases over 3 years (1999-2001) in the Celje region, Slovenia, covering 125 000 inhabitants. Data were recorded on an EMS form.

RESULTS

Two hundred and forty-four poisoning-related EMS interventions were recorded among a total of 4486 interventions (5.4%) corresponding to an average annual rate of 0.56 poisonings per 1000 inhabitants per year. Psychoactive agents were detected in 56.5% of the cases. Two-thirds of the poisonings took place outside patients' home. In 30% of the cases, the administration of poison was because of suicidal intentions. The most common substance ingested was alcohol alone or in combination with prescription or illegal drugs in 42.6% of cases, followed by drugs alone or in combination with alcohol in 39.2% cases. More than one-fifth of the poisonings were because of the use of illegal drugs. At the time of the arrival of EMS 23.5% of the patients were in coma. EMS applied antidote in 23.2% of the patients. After emergency care, 9.3% of the patients were still in coma, 15.6% were comatose, 26.6% were somnolent, 18.6% were disoriented and 30% had complete consciousness. Of these, 84.4% of the patients were admitted to hospital or specialized care and 15.6% were sent back home.

CONCLUSION

The pattern of poisoning is contrasted with that in other countries. The EMS proved to be a valuable resource for treatment of acute poisoning.

Clinical improvement of a patient with severe Wilson's disease after a single session of therapeutic plasma exchange

Here, we report a case of a 17-year old female with Wilson's disease presenting with progressive Coombs' negative hemolytic anemia and hepatic cirrhosis who was treated with one session of therapeutic plasma exchange (TPE) and clinically improved. In clinical situations where multiple sessions of TPE may not be possible, the use of a single session of TPE in conjunction with conventional therapy may be of benefit in preventing further clinical deterioration.

Early onset muscarinic manifestations after wild mushroom ingestion

Despite being a favorite delicacy, only 200–300 of the 5,000 known mushroom species have been clearly established to be safe for consumption. Cases of mushroom poisoning have been reported with diverse clinical syndromes. A syndromic classification of mushroom poisoning has recently been developed to facilitate early interventions. We present a series of five cases of mushroom poisoning with muscarinic manifestations to highlight the difficulties we faced with exact species and toxin identification and the importance of this syndromic classification. The common symptoms in our case series are blurred vision, diarrhea, vomiting, and abdominal cramps.

Toxicology in the critical care unit

Toxicologic conditions are encountered in critically ill patients due to intentional or unintentional misuse of or exposure to therapeutic or illicit drugs. Additionally, toxicities related to medical interventions may develop in hospitalized patients. This review focuses on recent developments in the field of critical care toxicology. Early interventions to decrease absorption or enhance elimination of toxins have limited value. Specific interventions to manage toxicities due to analgesics, sedative-hypnotics, antidepressants, antipsychotics, cardiovascular agents, alcohols, carbon monoxide, and cholinergic agents are reviewed. Hospital-acquired toxicities due to methemoglobinemia, propylene glycol, and propofol should be recognized and treated. The clinician is continually required to incorporate clinical judgment along with available scientific data and clinical evidence to determine the best therapy for toxicologic conditions.

Injectable nanocarriers for biodetoxification

Hospitals routinely treat patients suffering from overdoses of drugs or other toxic chemicals as a result of illicit drug consumption, suicide attempts or accidental exposures. However, for many life-threatening situations, specific antidotes are not available and treatment is largely based on emptying the stomach, administering activated charcoal or other general measures of intoxication support. A promising strategy for managing such overdoses is to inject nanocarriers that can extract toxic agents from intoxicated tissues. To be effective, the nanocarriers must remain in the blood long enough to sequester the toxic components and/or their metabolites, and the toxin bound complex must also remain stable until it is removed from the bloodstream. Here, we discuss the principles that govern the use of injectable nanocarriers in biodetoxification and review the pharmacological performance of a number of different approaches.

The approach to the patient with an unknown overdose

Toxic overdose can present with various clinical signs and symptoms. These may be the only clues to diagnosis when the cause of toxicity is unknown at the time of initial assessment. The prognosis and clinical course of recovery of a patient poisoned by a specific agent depends largely on the quality of care delivered within the first few hours in the emergency setting. Usually the drug or toxin can be quickly identified by a careful history, a directed physical examination, and commonly available laboratory tests. Once the patient has been stabilized, the physician must consider how to minimize the bioavailability of toxin not yet absorbed, which antidotes (if any) to administer, and if other measures to enhance elimination are necessary.

Long circulating lipid nanocapsules for drug detoxification

Uncoated and poly(ethylene glycol) (PEG)-decorated lipid nanocapsules (NC) prepared from medium chain triglycerides were investigated both in vitro and in vivo as parenteral detoxifying colloids for their ability to sequester haloperidol, docetaxel and paclitaxel. In vitro studies showed that the uptake depended on the nature of the drug and the composition of NC core and shell. In the case of haloperidol, maximal affinity was achieved upon incorporation of a complexing fatty acid. In plasma lipoprotein distribution studies, the association of both haloperidol and docetaxel into triglyceride-rich lipoprotein fraction was significantly increased in the presence of NC. The ability of the NC to lower the free drug concentrations in incubation medium was confirmed by cytotoxicity studies, where the antiproliferative activity of docetaxel was significantly decreased in the presence of NC. Using docetaxel as drug model, the NC were finally evaluated for their uptake potential in mice by one of the following administration sequences between the drug solution (Taxotere, DTX) and NC: NC-DTX, PEG(NC)-DTX and DTX-PEG(NC). Irrespective of the administration sequence, the NC increased the blood levels of docetaxel due to the in situ sequestration of drug by the circulating carrier. These findings suggest that lipid NC could be used as a non-specific mode to deal with the sequestration of molecules with high affinity for oils.

Street drug abuse leading to critical illness

Critical care physicians are frequently confronted with intoxicated patients who have used street drugs. In the last decade there has been an upward trend in the use of these substances, particularly amongst adolescents and young adults in large urban areas. In excess quantities all street drugs can lead to critical illness. Early and appropriate medical attention by emergency medicine physicians and intensivists can improve outcomes. In this review article we intend to familiarize critical care physicians with the most common street drugs such as amphetamines, ecstasy, cocaine, gamma hydroxybutyrate, opioids, and phencyclidine.

Position of immunological techniques in screening in clinical toxicology

There is a continuing increase in the use of immunological techniques in the field of clinical toxicology. This is primarily due to the rapidity by which analytical results are now required, and can be obtained, following the testing of individuals for drug use. There has recently been an increase in the repertoire of assays now available to testing laboratories (e.g., buprenorphine and heroin metabolite assays), with the techniques themselves becoming increasingly more specific for the drugs and/or metabolites being monitored (e.g., methadone metabolite assays). The near patient testing (NPT), or point-of-care testing (POCT), devices are now several generations forward from their inception, with some tests now approaching the sensitivity and specificity of automated laboratory-based methods. This review has been collated from the literature to illustrate some of the possible reasons for the move towards the increasing use of immunological techniques, and to highlight some of the advantages and disadvantages associated with such drug screening methods. In particular, it has been shown that it is important to determine, monitor and review the knowledge and training of the individual using the technique. In addition, quality control and quality assessment are paramount to ensure the validity of any drug testing being performed. It has also been shown that it is vital to maintain and develop the relationships between the staff performing the testing, the laboratory (if the testing is performed using NPT devices), and the clinicians utilising the results obtained from drug testing. Without these links, interpretive errors could arise which could adversely affect the diagnosis and management of patients.

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.

Managing Suicide Attempts: Guidelines for the Primary Care Physician

The management of patients who have made suicide attempts is a responsibility that frequently falls to the primary care physician. For this reason, it is important that the physician have a clear strategy for dealing with the suicidal patient in the office, hospital, and emergency room. In the acute situation, the first priority is to stabilize the patient and ensure his or her medical safety. Once this is accomplished, history and circumstances of the attempt can be assessed, along with likelihood of recurrence of the attempt. This article reviews guidelines for evaluating suicide risk. The importance of the patient-physician relationship is noted, particularly in regard to prevention of future suicide attempts. With a focused, thorough approach to the suicidal patient, which incorporates both medical and psychiatric considerations, the primary care physician can ameliorate the patient's acute situation and facilitate the coordination of care with appropriate psychiatric resources.