High-dose insulin should be used before vasopressors/inotropes in calcium-channel blocker toxicity.

High-dose insulin (HDI) therapy with adapted glucose supplementation to maintain euglycaemia has been suggested to treat calcium-channel blocker (CCB) poisonings. Its underlying mechanisms of action are now well documented. We present a narrative review of the published experimental studies, case reports and experts' opinions to support the effectiveness and safety of HDI in the treatment of CCB poisoning. Our review strongly encourages the use of HDI as first-line therapy in CCB-poisoned patients in the presence of cardiovascular compromise, especially if cardiac function impairment has been diagnosed, before, but without delaying, the administration of vasopressors/inotropic drugs.

Acute Rubigine® Poisoning in Martinique a French Overseas Department of America: Clinical Characteristics and Prognostic Factors.

Rubigine® is an anti-rust stain remover containing fluorides which is believed to have been the cause of many deaths in Martinique. However, after the modification of its composition in 2006, serious poisoning from old formulas containing fluorides persisted. Our main objective was to determine the clinical characteristics and prognostic factors of these intoxications. Methods: Any patient admitted to the Martinique University Hospital for acute Rubigine® poisoning was included from 1 January 2000 to 31 December 2016. Usual demographic and clinical data were collected and comparisons between surviving and deceased patients made using a univariate analysis and logistic regression. Results: Fifty-five patients were included (mean age: 43 years; sex ratio M/F: 1.1), and the main clinical characteristics were: changes in electrocardiogram (ECG) (80%), digestive system disorders (75%), and neurological disorders (12%). The main features linked to death were the presence of hydrofluoric acid (p < 0.0001), age over 55 years (p = 0.01), hypocalcemia after the initial intravenous calcium supplementation (p = 0.0003), diarrhea (p < 0.0001), hypersialorrhea (p < 0.0001), myocardial excitability (p < 0.0001), and state of shock (p < 0.0001). Three patients required circulatory support by venous-arterial ECMO. Mortality was 10.9%. Conclusions: Rubigine® poisoning is responsible for significant morbidity and mortality. Fortunately, its incidence as well as mortality has sharply decreased in Martinique thanks to the measures taken by the French state. This retrospective work nevertheless shows that acute intoxication by the old formula of Rubigine® remains the main factor of poor prognosis.

High-Dose Dexamethasone and Oxygen Support Strategies in Intensive Care Unit Patients With Severe COVID-19 Acute Hypoxemic Respiratory Failure: The COVIDICUS Randomized Clinical Trial.

Importance: The benefit of high-dose dexamethasone and oxygenation strategies vs standard of care for patients with severe acute hypoxemic respiratory failure (AHRF) caused by COVID-19 pneumonia is debated. Objectives: To assess the benefit of high-dose dexamethasone compared with standard of care dexamethasone, and to assess the benefit of high-flow nasal oxygen (HFNo2) or continuous positive airway pressure (CPAP) compared with oxygen support standard of care (o2SC). Design, Setting, and Participants: This multicenter, placebo-controlled randomized clinical trial was conducted in 19 intensive care units (ICUs) in France from April 2020 to January 2021. Eligible patients were consecutive ICU-admitted adults with COVID-19 AHRF. Randomization used a 2 × 3 factorial design for dexamethasone and oxygenation strategies; patients not eligible for at least 1 oxygenation strategy and/or already receiving invasive mechanical ventilation (IMV) were only randomized for dexamethasone. All patients were followed-up for 60 days. Data were analyzed from May 26 to July 31, 2021. Interventions: Patients received standard dexamethasone (dexamethasone-phosphate 6 mg/d for 10 days [or placebo prior to RECOVERY trial results communication]) or high-dose dexamethasone (dexamethasone-phosphate 20 mg/d on days 1-5 then 10 mg/d on days 6-10). Those not requiring IMV were additionally randomized to o2SC, CPAP, or HFNo2. Main Outcomes and Measures: The main outcomes were time to all-cause mortality, assessed at day 60, for the dexamethasone interventions, and time to IMV requirement, assessed at day 28, for the oxygenation interventions. Differences between intervention groups were calculated using proportional Cox models and expressed as hazard ratios (HRs). Results: Among 841 screened patients, 546 patients (median [IQR] age, 67.4 [59.3-73.1] years; 414 [75.8%] men) were randomized between standard dexamethasone (276 patients, including 37 patients who received placebo) or high-dose dexamethasone (270 patients). Of these, 333 patients were randomized among o2SC (109 patients, including 56 receiving standard dexamethasone), CPAP (109 patients, including 57 receiving standard dexamethasone), and HFNo2 (115 patients, including 56 receiving standard dexamethasone). There was no difference in 60-day mortality between standard and high-dose dexamethasone groups (HR, 0.96 [95% CI, 0.69-1.33]; P = .79). There was no significant difference for the cumulative incidence of IMV criteria at day 28 among o2 support groups (o2SC vs CPAP: HR, 1.08 [95% CI, 0.71-1.63]; o2SC vs HFNo2: HR, 1.04 [95% CI, 0.69-1.55]) or 60-day mortality (o2SC vs CPAP: HR, 0.97 [95% CI, 0.58-1.61; o2SC vs HFNo2: HR, 0.89 [95% CI, 0.53-1.47]). Interactions between interventions were not significant. Conclusions and Relevance: In this randomized clinical trial among ICU patients with COVID-19-related AHRF, high-dose dexamethasone did not significantly improve 60-day survival. The oxygenation strategies in patients who were not initially receiving IMV did not significantly modify 28-day risk of IMV requirement. Trial Registration: ClinicalTrials.gov Identifier: NCT04344730; EudraCT: 2020-001457-43.

Case series of massive direct oral anticoagulant ingestion-Treatment and pharmacokinetics data.

BACKGROUND: Direct oral anticoagulants (DOAC) are widely used due to favourable benefit/risk ratio. However, consequences of massive ingestion have been poorly investigated. OBJECTIVES: We aimed to report outcome and pharmacokinetic parameters in patients who massively ingested DOACs. METHODS: We conducted a 5-year cohort study including consecutive massive DOAC ingestion patients admitted to two critical care departments. Patients were managed in accordance with standards of care. We collected the main history, clinical, laboratory, management and outcome data. The time-course of plasma DOAC concentrations measured using specific assays was modelled. RESULTS: Twelve patients (3F/9M; age, 55 years [41-63], median [25th-75th percentiles]) were included. Ingestions involved rivaroxaban (n = 7), apixaban (n = 3) and dabigatran (n = 2), with presumed doses of 9.4-fold [5.0-22.0] the full daily dose. Six patients received activated charcoal but no antidote nor blood-derived product. No bleeding was observed. One patient died due to refractory cardiogenic shock related to bisoprolol co-intoxication. Highest observed peak plasma concentrations were 1720 ng/ml (rivaroxaban), 750 ng/ml (apixaban) and 644 ng/ml (dabigatran). Times to reach DOAC concentration below 50 ng/ml were ~20-45 h (rivaroxaban), ~125 h (apixaban) and ~30-50 h (dabigatran). Elimination half-lives were 2.5-25.5 h (rivaroxaban), 22.0 and 36.5 h (apixaban), and 5.8 and 15.5 h (dabigatran), with substantial interindividual variability and prolongation in case of cardiovascular failure related to co-intoxicants. Charcoal administration, even if delayed, may have contributed to limit toxicity, possibly by reducing absorption and/or enteroenteric recycling. CONCLUSION: No bleeding was observed in this series of massive DOAC ingestions despite elevated plasma concentrations. No patient required specific haemostatic agents. Charcoal administration should be considered to limit toxicity.

Preclinical evaluation of the neutralizing ability of a monospecific antivenom for the treatment of envenomings by Bothrops lanceolatus in Martinique.

Bothrops lanceolatus is an endemic viperid species in the Lesser Caribbean island of Martinique. Envenomings by this species are characterized by local and systemic effects, among which the development of thrombosis in various organs is the most severe complication. An experimental toxicological characterization of this venom was performed using in vivo mouse tests and various in vitro assays. The venom induced lethal, local and systemic hemorrhagic, edema-forming, myotoxic, thrombocytopenic, proteinase and phospholipase A2 activities. The preclinical efficacy of a batch of monospecific Bothrofav® antivenom currently in use in Martinique was assessed. The antivenom was highly effective in the neutralization of all activities tested, in agreement with its described clinical efficacy. This batch of antivenom showed a higher preclinical efficacy as compared to a previous batch used in the past.

Experts Consensus Recommendations for the Management of Calcium Channel Blocker Poisoning in Adults.

OBJECTIVE: To provide a management approach for adults with calcium channel blocker poisoning. DATA SOURCES, STUDY SELECTION, AND DATA EXTRACTION: Following the Appraisal of Guidelines for Research & Evaluation II instrument, initial voting statements were constructed based on summaries outlining the evidence, risks, and benefits. DATA SYNTHESIS: We recommend 1) for asymptomatic patients, observation and consideration of decontamination following a potentially toxic calcium channel blocker ingestion (1D); 2) as first-line therapies (prioritized based on desired effect), IV calcium (1D), high-dose insulin therapy (1D-2D), and norepinephrine and/or epinephrine (1D). We also suggest dobutamine or epinephrine in the presence of cardiogenic shock (2D) and atropine in the presence of symptomatic bradycardia or conduction disturbance (2D); 3) in patients refractory to the first-line treatments, we suggest incremental doses of high-dose insulin therapy if myocardial dysfunction is present (2D), IV lipid-emulsion therapy (2D), and using a pacemaker in the presence of unstable bradycardia or high-grade arteriovenous block without significant alteration in cardiac inotropism (2D); 4) in patients with refractory shock or who are periarrest, we recommend incremental doses of high-dose insulin (1D) and IV lipid-emulsion therapy (1D) if not already tried. We suggest venoarterial extracorporeal membrane oxygenation, if available, when refractory shock has a significant cardiogenic component (2D), and using pacemaker in the presence of unstable bradycardia or high-grade arteriovenous block in the absence of myocardial dysfunction (2D) if not already tried; 5) in patients with cardiac arrest, we recommend IV calcium in addition to the standard advanced cardiac life-support (1D), lipid-emulsion therapy (1D), and we suggest venoarterial extracorporeal membrane oxygenation if available (2D). CONCLUSION: We offer recommendations for the stepwise management of calcium channel blocker toxicity. For all interventions, the level of evidence was very low.

Emerging technologies and challenges for better and safer drugs.

Regardless of stringent safety regulations and increased compound selectivity by pharmaceutical companies, prediction of toxicity in humans is still far from perfect and adverse drug reactions are still detected after drug marketing. High costs of failures due to toxicity has led pharmaceutical companies to search for screening methods that would allow detection of toxicity issues at an early stage and improve their preclinical and clinical toxicology. Thanks to the last decade's biotechnology revolution, new technologies like toxicogenomics have demonstrated the capacity to improve toxicity assessment. However, our understanding of toxicological mechanisms is still incomplete and a wide range of approaches must be used to gain insight into toxicity issues. Consequently, an array of in silico, in vitro and in vivo methods is utilized to predict toxicity and its causative mechanisms, improving drug development processes and minimizing costs of failure.

[Extracorporeal life support for poisonings with cardiotoxicants]. / Assistance circulatoire dans les intoxications par cardiotropes.

Acute poisonings with cardiotoxicants are responsible of significant morbidity and incompressible mortality, mainly among youths. Their incidence is increasing. Death mainly results from cardiac failure refractory to pharmacological treatments as well as sudden cardiac arrest refractory to cardiopulmonary resuscitation. Determination of the exact mechanism of shock is essential to guide adequate treatments. Treatment is supportive including high-dosage catecholamines and may require antidotes. Administration of other inotropic agents (including glucagon, phosphodiesterase inhibitors, calcium salts, and euglycemic insulin) may be discussed, although their efficacy is still not clearly established. Extracorporeal life support allows organ perfusion until reversal of cardiac dysfunction and elimination of the toxicant. Several cases of survival using this exceptional technique were reported in the literature. Thus, based on these reports, extracorporeal life support has gained a recognized place in the therapeutic arsenal of acute poisonings.

Clinical review: aggressive management and extracorporeal support for drug-induced cardiotoxicity.

Poisoning may induce failure in multiple organs, leading to death. Supportive treatments and supplementation of failing organs are usually efficient. In contrast, the usefulness of cardiopulmonary bypass in drug-induced shock remains a matter of debate. The majority of deaths results from poisoning with membrane stabilising agents and calcium channel blockers. There is a need for more aggressive treatment in patients not responding to conventional treatments. The development of new antidotes is limited. In contrast, experimental studies support the hypothesis that cardiopulmonary bypass is life-saving. A review of the literature shows that cardiopulmonary bypass of the poisoned heart is feasible. The largest experience has resulted from the use of peripheral cardiopulmonary bypass. However, a literature review does not allow any conclusions regarding the efficiency and indications for this invasive method. Indeed, the majority of reports are single cases, with only one series of seven patients. Appealing results suggest that further studies are needed. Determination of prognostic factors predictive of refractoriness to conventional treatment for cardiotoxic poisonings is mandatory. These prognostic factors are specific for a toxicant or a class of toxicants. Knowledge of them will result in clarification of the indications for cardiopulmonary bypass in poisonings.

The role of insulin and glucose (hyperinsulinaemia/euglycaemia) therapy in acute calcium channel antagonist and beta-blocker poisoning.

The inotropic effect of insulin has been long established. High-dose (0.5-1 IU/kg/hour) insulin, in combination with a glucose infusion to maintain euglycaemia (hyperinsulinaemia/euglycaemia therapy), has been proposed as a treatment for calcium channel antagonist (CCA) and beta-adrenoceptor antagonist (beta-blocker) poisonings. However, the basis for its beneficial effect is poorly understood.CCAs inhibit insulin secretion, resulting in hyperglycaemia and alteration of myocardial fatty acid oxidation. Similarly, blockade of beta(2)-adrenoceptors in beta-blocker poisoning results in impaired lipolysis, glycogenolysis and insulin release. Insulin administration switches cell metabolism from fatty acids to carbohydrates and restores calcium fluxes, resulting in improvement in cardiac contractility. Experimental studies in verapamil poisoning have shown that high-dose insulin significantly improved survival compared with calcium salts, epinephrine or glucagon. In several life-threatening poisonings in humans, the administration of high-dose insulin produced cardiovascular stabilisation, decreased the catecholamine vasopressor infusion rate and improved the survival rate. In a canine model of propranolol intoxication, high-dose insulin provided a sustained increase in systemic blood pressure, cardiac performance and survival rate compared with glucagon or epinephrine. In contrast, insulin had no effect on heart rate and electrical conduction in the myocardium. In another study, high-dose insulin reversed the negative inotropic effect of propranolol to 80% of control function and normalised heart rate. High-dose insulin produced a significant decrease in the left ventricular end-diastolic pressure and a significant increase in the stroke volume and cardiac output. The vasodilator effect was explained by an enhanced cardiac output leading to withdrawal of compensatory vasoconstriction. No clinical studies have yet been performed. Although not effective in all cases, we recommend hyperinsulinaemia/euglycaemia therapy in patients with severe CCA poisoning who present with hypotension and respond poorly to fluid, calcium salts, glucagon and catecholamine infusion. However, careful monitoring of blood glucose and serum potassium concentrations is required to avoid serious adverse effects. More clinical data are needed before this therapy can be recommended in beta-blocker poisoning. There is a need for large prospective clinical trials to confirm safety and efficacy of hyperinsulinaemia/euglycaemia therapy in both CCA and beta-blocker poisoning.

Antidotal treatment of cyanide poisoning.

Cyanide poisoning may result from different exposures: residential fires, industrial accidents, drug and plant intoxication. Clinical features include coma, respiratory arrest and cardiovascular collapse. The biological hallmark is lactic acidosis. A plasma lactate concentration > or = 10 mmol/L in fire victims without severe burns and > or = 8 mmol/L in pure cyanide poisoned patients is a sensitive and specific indicator of cyanide intoxication. Many antidotes are available and efficient. However, therapeutic strategies are still debated. Our objective was to compare conventional treatments to hydroxocobalamin. This article reviews the literature on cyanide poisoning treatment. Conventional treatment of cyanide poisoning includes decontamination, supportive and specific treatment. Decontamination should be adapted to the route of poisoning and never postpone supportive treatment. Basic life support includes immediate administration of high flow of oxygen, airway protection and cardiopulmonary resuscitation. Advanced life support includes mechanical ventilation, catecholamine and sodium bicarbonate infusion. Supportive treatment is efficient but does not modify the time course or the body burden of cyanide. Numerous antidotes are available. Oxygen counteracts efficiently cyanide action at the mitochondrial level. Sodium thiosulfate, methemoglobin forming agents and cobalt compounds act efficiently by complexing or transforming cyanide into non-toxic stable derivatives. However, regarding the main clinical condition of cyanide poisoning, i.e. smoke inhalation, we should take into account not only the efficiency of antidotes but also their safety. Sodium thiosulfate is both efficient and safe, but acts with delay. Methemoglobin-forming agents are potent, but due to the transformation of hemoglobin into methemoglobin, they impair tissue delivery of oxygen. Experimental data showed increased mortality in carbon monoxide- and cyanide-poisoned rats treated with these agents. Cobalt EDTA and hydroxocobalamin are efficient and act immediately. Cobalt EDTA is more potent on a molar basis; however, numerous side effects limit its use to evidenced cyanide poisoning. In a prospective study, hydroxocobalamin appeared safe in fire victims with or without cyanide poisoning. The only reported side effect was a red coloration of skin and urine. In conclusion, antidotes are beneficial in cyanide poisoning. In suspected cyanide-poisoned patients, we recommend the use of hydroxocobalamin as first-line antidote, owing to its safety. In massive cyanide poisoning, due to the limited potency of hydroxocobalamin, continuous infusion of sodium thiosulfate should be associated.