title: Treatment for calcium channel blocker poisoning: a systematic review.
abstract: BACKGROUND
  Calcium channel blocker poisoning is a common and sometimes life-threatening ingestion.
  
  
  OBJECTIVE
  To evaluate the reported effects of treatments for calcium channel blocker poisoning. The primary outcomes of interest were mortality and hemodynamic parameters. The secondary outcomes included length of stay in hospital, length of stay in intensive care unit, duration of vasopressor use, functional outcomes, and serum calcium channel blocker concentrations.
  
  
  METHODS
  Medline/Ovid, PubMed, EMBASE, Cochrane Library, TOXLINE, International pharmaceutical abstracts, Google Scholar, and the gray literature up to December 31, 2013 were searched without time restriction to identify all types of studies that examined effects of various treatments for calcium channel blocker poisoning for the outcomes of interest. The search strategy included the following Keywords: [calcium channel blockers OR calcium channel antagonist OR calcium channel blocking agent OR (amlodipine or bencyclane or bepridil or cinnarizine or felodipine or fendiline or flunarizine or gallopamil or isradipine or lidoflazine or mibefradil or nicardipine or nifedipine or nimodipine or nisoldipine or nitrendipine or prenylamine or verapamil or diltiazem)] AND [overdose OR medication errors OR poisoning OR intoxication OR toxicity OR adverse effect]. Two reviewers independently selected studies and a group of reviewers abstracted all relevant data using a pilot-tested form. A second group analyzed the risk of bias and overall quality using the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) checklist and the Thomas tool for observational studies, the Institute of Health Economics tool for Quality of Case Series, the ARRIVE (Animal Research: Reporting In Vivo Experiments) guidelines, and the modified NRCNA (National Research Council for the National Academies) list for animal studies. Qualitative synthesis was used to summarize the evidence. Of 15,577 citations identified in the initial search, 216 were selected for analysis, including 117 case reports. The kappa on the quality analysis tools was greater than 0.80 for all study types.
  
  
  RESULTS
  The only observational study in humans examined high-dose insulin and extracorporeal life support. The risk of bias across studies was high for all interventions and moderate to high for extracorporeal life support. High-dose insulin. High-dose insulin (bolus of 1 unit/kg followed by an infusion of 0.5-2.0 units/kg/h) was associated with improved hemodynamic parameters and lower mortality, at the risks of hypoglycemia and hypokalemia (low quality of evidence). Extracorporeal life support. Extracorporeal life support was associated with improved survival in patients with severe shock or cardiac arrest at the cost of limb ischemia, thrombosis, and bleeding (low quality of evidence). Calcium, dopamine, and norepinephrine. These agents improved hemodynamic parameters and survival without documented severe side effects (very low quality of evidence). 4-Aminopyridine. Use of 4-aminopyridine was associated with improved hemodynamic parameters and survival in animal studies, at the risk of seizures. Lipid emulsion therapy. Lipid emulsion was associated with improved hemodynamic parameters and survival in animal models of intravenous verapamil poisoning, but not in models of oral verapamil poisoning. Other studies. Studies on decontamination, atropine, glucagon, pacemakers, levosimendan, and plasma exchange reported variable results, and the methodologies used limit their interpretation. No trial was documented in humans poisoned with calcium channel blockers for Bay K8644, CGP 28932, digoxin, cyclodextrin, liposomes, bicarbonate, carnitine, fructose 1,6-diphosphate, PK 11195, or triiodothyronine. Case reports were only found for charcoal hemoperfusion, dialysis, intra-aortic balloon pump, Impella device and methylene blue.
  
  
  CONCLUSIONS
  The treatment for calcium channel blocker poisoning is supported by low-quality evidence drawn from a heterogeneous and heavily biased literature. High-dose insulin and extracorporeal life support were the interventions supported by the strongest evidence, although the evidence is of low quality.
authors.affiliation: Ontario and Manitoba Poison Centre , Toronto, ON , Canada.
authors.forename: M
authors.initials: M
authors.lastname: St-Onge
authors.forename: P-A
authors.initials: PA
authors.lastname: Dubé
authors.forename: S
authors.initials: S
authors.lastname: Gosselin
authors.forename: C
authors.initials: C
authors.lastname: Guimont
authors.forename: J
authors.initials: J
authors.lastname: Godwin
authors.forename: P M
authors.initials: PM
authors.lastname: Archambault
authors.forename: J-M
authors.initials: JM
authors.lastname: Chauny
authors.forename: A J
authors.initials: AJ
authors.lastname: Frenette
authors.forename: M
authors.initials: M
authors.lastname: Darveau
authors.forename: N
authors.initials: N
authors.lastname: Le Sage
authors.forename: J
authors.initials: J
authors.lastname: Poitras
authors.forename: J
authors.initials: J
authors.lastname: Provencher
authors.forename: D N
authors.initials: DN
authors.lastname: Juurlink
authors.forename: R
authors.initials: R
authors.lastname: Blais
mesh_terms: D000818:Animals; D002121:Calcium Channel Blockers / Q000097:blood / Q000506:poisoning*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D062787:Drug Overdose / Q000401:mortality / Q000628:therapy*; D017408:Guidelines as Topic; D006760:Hospitalization; D006801:Humans; D007328:Insulin / Q000627:therapeutic use; D007902:Length of Stay; D064887:Observational Studies as Topic; D016896:Treatment Outcome; D014662:Vasoconstrictor Agents / Q000008:administration & dosage
chemical_list: D002121:Calcium Channel Blockers; D007328:Insulin; D014662:Vasoconstrictor Agents
keywords: Antidotes; Calcium channel blockers; Cardiotoxins; Drug overdose; Poisoning; Toxicity; Treatment