Toxicology in the critical care unit

Overview of the bioanalytical methods used for the determination of benzodiazepines in biological samples and their suitability for emergency toxicological analysis

Benzodiazepines are one of the most widely used classes of drugs around the world. They are medically used in different therapeutic areas including insomnia, anxiety, epilepsy, and anesthesia. Unfortunately, these drugs are very widespread in the illicit market for recreational purposes and cause drug dependence, traffic accidents, and criminality. Furthermore, benzodiazepine misuse leads to acute poisoning cases that often end up in hospital emergency rooms. Therefore, it is crucial for hospitals to possess straightforward and efficient bioanalytical techniques that enable the swift detection of benzodiazepines in biological samples. This review provides a general overview of the different bioanalytical techniques used for the detection and quantification of benzodiazepines in biological samples and emphasizes their suitability for emergency toxicological analyzes.

Prediction Model of Acute Respiratory Failure in Patients with Acute Pesticide Poisoning by Intentional Ingestion: Prediction of Respiratory Failure in Pesticide Intoxication (PREP) Scores in Cohort Study

Acute respiratory failure is the primary cause of mortality in patients with acute pesticide poisoning. The aim of the present study was to develop a new and efficient score system for predicting acute respiratory failure in patients with acute pesticide poisoning. This study was a retrospective observational cohort study comprised of 679 patients with acute pesticide poisoning by intentional poisoning. We divided this population into a ratio of 3:1; training set (n = 509) and test set (n = 170) for model development and validation. Multivariable logistic regression models were used in developing a score-based prediction model. The Prediction of Respiratory failure in Pesticide intoxication (PREP) scoring system included a summation of the integer scores of the following five variables; age, pesticide category, amount of ingestion, Glasgow Coma Scale, and arterial pH. The PREP scoring system developed accurately predicted respiratory failure (AUC 0.911 [0.849−0.974], positive predictive value 0.773, accuracy 0.873 in test set). We came up with four risk categories (A, B, C and D) using PREP scores 20, 40 and 60 as the cut-off for mechanical ventilation requirement risk. The PREP scoring system developed in the present study could predict respiratory failure in patients with pesticide poisoning, which can be easily implemented in clinical situations. Further prospective studies are needed to validate the PREP scoring system.

Epidemiology of Self-poisoning with Drug in the Central Anatolian Region in Turkey

Aim: Deliberate self-poisoning (DSP) is a common cause of intensive care hospitalization among young adults and a serious health problem worldwide. Demographic data vary according to geographical and sociocultural characteristics of the regions. In recent years, studies investigating epidemiological features and prognosis of these patients have increased. In our study, we retrospectively examined patients who committed suicide with drugs and were treated in the ICU of our hospital.

Materials and Methods: The files of 148 patients who took drugs or substances for committing suicide and who were hospitalized in the ICU of Aksaray Training and Research Hospital between 2015 and 2019 were examined. Demographic data of the patients, type of the agent used in the suicide, time to reach hospital, treatment methods applied, length of hospital stay, vital signs, complications, need for intubation, and mortality rates were recorded.

Results: Mean age of the 148 patients who took drugs for suicide was 26.7. Female rate was 73%. The most frequently used drug for suicide was paracetamol (34.4%). Antidepressants took the second place and were followed by drugs in the NSAID group. The duration of admission in the hospital after taking the medicine ranged from 1 to 6 h, while it was less than 3 h in 68.2% of the patients. In most suicide patients, the treatment method was in the form of intravenous fluid and supportive therapy (95%). N-acetyl cysteine (paracetamol intoxication) was used in 7% of the patients, an intubation requirement developed in 2.7%, and three patients taking organophosphate died.

Conclusion: In studies conducted in developing countries such as Turkey, female sex (63%-71%) and 25 years of age have been found to be the proportion of the patients (56%-63%), whereas our study found even higher ratios compared to those (73%-66%). In studies conducted in developed countries, most commonly used agents for suicide were benzodiazepines and tricyclic antidepressants, while the most common suicide agent was paracetamol in our study. We believe that the reason for this could be the possibility of accessing the agent without a prescription.

Early Clinical Outcome of Acute Poisoning Cases Treated in Intensive Care Unit

INTRODUCTION

A variety of factors have influenced the significant incidence of morbidity and mortality of acute poisoning and the timely recognition and properly management of critically ill poisoned patients is a key component. The aim of this study is to reveal the reasons for ICU admission of acutely poisoned patients, the main factors influencing the course and outcome of patients in relation with clinical approaches applied, available resources and infrastructure of treatment.

MATERIALS AND METHODS

This is a retrospective study based on most reachable variables extracted from patients' medical records and ED registers of patients admitted at the medical ICU of "Mother Teresa" University Hospital in Tirana over two (2012-2013) years. Demography, time of exposure, etiology and circumstances of poisonings, assessment and treatment, reasons for ICU admission, course and outcome were duly obtained.

RESULTS

The number of ICU treated patients was 118, consisting in 47.4% (56) males and 52.5% (62) females which represented 10.2% of poisoned patients admitted during this two-year-period in ED and 9.2% of other etiology ICU admitted patients. Mean was 42.6 years for males, and 38 years for females. About 55.9% were urban residents and 44% rural ones. The elapsed time from toxic exposure to treatment initiation had varied between 2-6 hours, 44% arrived in the hospital <4 hours. The toxic exposures were intentional in 87.2% of cases, with a male:female ratio was 0.8:1. Agrochemicals such as Aluminum phosphide and organophosphates were involved in 77.1% of cases. Cardiovascular collapse and respiratory failure were the main clinical syndromes encountered. Mechanical ventilation was required in 31.4% of patients. The length of ICU stay was 2.73 (0.96) days and the mortality was 54.2%.

CONCLUSION

This study evidenced that highly lethal toxicants used in poisoning acts such as agrochemicals, high rate of suicide, notwithstanding the infrastructure and resources available employed for ICU patients' treatment, all had played a role in the very high rate of mortality in this cluster of patients.

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.

Dapsone-induced methemoglobinemia: a primer for clinicians

OBJECTIVE

To present a comprehensive review of dapsone-induced methemoglobinemia and its management.

DATA SOURCES

Literature retrieval was accessed through MEDLINE (1966-March 2011), Cochrane Library, and EMBASE, using the terms dapsone and methemoglobinemia.

STUDY SELECTION AND DATA EXTRACTION

All case reports, small case series, and randomized controlled trials published in English were evaluated. Because of the absence of comprehensive updates on this topic since 1996, publications between 1997 and March 2011 were included in this review.

DATA SYNTHESIS

Between 1997 and March 2011, the majority of publications describing methemoglobinemia associated with dapsone use reported this adverse effect at therapeutic doses. Excluding overdose situations, 18 described symptomatic dapsone-associated methemoglobinemia and clinical presentation ranging from cyanosis to dyspnea. In almost all of the accounts, patients had a concurrent event such as anemia or pneumonia, suggesting an interplay between these comorbidities and the onset of symptomatic methemoglobinemia. Delayed hemolytic anemia was seen in patients with high methemoglobin levels at presentation. Management in most cases consisted of administration of methylene blue. Overall, most reports described a successful outcome, and no mortality resulted from methemoglobinemia associated with therapeutic use.

CONCLUSIONS

Clinicians should recognize methemoglobinemia as an adverse effect associated with dapsone use and the potential factors that precipitate it. They should also know how to promptly and effectively manage this event.