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The use of an extracorporeal treatment (ECTR) in a poisoned patient may be life-saving in a limited number of scenarios. The decision-processes surrounding the use of ECTR in poisoning is complex: most nephrologists are not trained to assess a poisoned patient while clinical toxicologists rarely prescribe ECTRs. Deciding on which ECTR is most appropriate for a poison requires a good understanding of the poison's physicochemical and pharmacokinetic properties. Further, a detailed understanding of the capabilities and limitations of the different ECTRs can be useful to select the most appropriate ECTR for a given clinical situation. This manuscript provides a stepwise approach to assess the usefulness of ECTRs in poisoning.

Background: Drug overdose is the leading cause of injury-related fatality in the US, and respiratory failure remains a major source of morbidity and mortality. However, neither the incidence nor risk factors for respiratory failure in overdose patients are currently known. Objectives: To identify the incidence and risk factors for respiratory failure following acute drug overdose. Methods: Secondary data analysis was performed from a prospective cohort of adult ED patients with acute drug overdose at two urban tertiary-care hospitals over a 5-year period. Excluded were patients with alternate diagnoses, anaphylaxis, chronic drug toxicity, and missing outcome data. ED clinical data included demographics, congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD defined as asthma, chronic bronchitis, or emphysema), drug information/screens, blood gas analysis, indications for endotracheal intubation (ETI), details of ETI (location, drugs, complications), and inhospital mortality. The study outcome was respiratory failure defined as the requirement for mechanical ventilation. Assuming 4% incidence of respiratory failure, we calculated the need to analyze 2500 patients to show 150% increased risk from common predictors with an 80% power. Univariate analysis (chi-square, t-test), 95% confidence intervals (CI), and multivariable logistic regression were performed with SPSS software. Results: We analyzed 2,497 patients (mean age 45, 54% male) of whom 87 (3.5%) had respiratory failure requiring ETI. Prehospital ETI was slightly associated with increased mortality (OR 2.0, p=0.28) compared with ED and inpatient ETI. Complications of ETI included desaturation (3.4%) and bradycardia (1%). Risk factors for respiratory failure included older age (p=0.06), and history of COPD (p<0.001); sex, type of drug exposures, and CHF had no association. After controlling for confounders, COPD was associated with a significantly increased risk of respiratory failure (adjusted OR 6.6, CI 3.5-12.3). Pati!

Background: ED patients with acute drug overdose have been shown to suffer adverse cardiovascular events, but prediction of these events is difficult. Objectives: To validate previously derived features of the initial ECG associated with adverse cardiovascular events in this population. Methods: We performed a prospective validation cohort study to evaluate adult ED patients with acute drug overdose at two urban university hospitals over 5 years in whom ED admission ECGs were performed. Excluded were patients with alternate diagnoses, anaphylaxis, chronic drug toxicity, and missing outcome data. Adverse cardiovascular events were defined as any of the following: shock (vasopressor requirement), myocardial injury (MI, elevated troponin), ventricular dysrythmia, or cardiac arrest (pulseless). Blinded cardiologists interpreted ECGs for rhythm, intervals, QT dispersion, ischemia (T wave inversion, ST depression), and infarction (ST elevation, Q waves). Diagnostic test characteristics of the previously derived ECG rule (ectopy, non-sinus rhythm, QTc), as well as univariate statistics, odds ratios (OR), and 95% confidence intervals (CI) were calculated. Assuming 10% prevalence of predictor variables and baseline 8% adverse cardiovascular event rate in the population, we calculated the need to enroll 552 patients to show three-fold increased risk per factor with 80% power and 5% alpha. Results: Of 589 acute drug overdose patients who met inclusion criteria (48% male, mean age 42), there were 95 adverse cardiovascular events (39 shock, 64 MI, 26 dysrhythmia, 16 cardiac arrest). The most common drug exposures were benzodiazepines, opioids, and acetaminophen. All previously derived criteria were highly predictive of adverse events, with QTc >500 ms the highest risk feature associated with over 10-fold increased adverse cardiovascular event risk (OR 11.2, CI 4.6-27). All high-risk ECG features as well as diagnostic test characteristics of the ECG rule are presented in Table 217. Conclusion: This study val!