Fatal nifedipine ingestions in children

Intensive Care Interventions Among Children With Toxicologic Exposures to Cardiovascular Medications

OBJECTIVES

Interventions requiring a PICU are rare in toxicologic exposures, but cardiovascular medications are high-risk exposures due to their hemodynamic effects. This study aimed to describe prevalence of and risk factors for PICU interventions among children exposed to cardiovascular medications.

DESIGN

Secondary analysis of Toxicology Investigators Consortium Core Registry from January 2010 to March 2022.

SETTING

International multicenter research network of 40 sites.

PATIENTS

Patients 18 years old or younger with acute or acute-on-chronic toxicologic exposure to cardiovascular medications. Patients were excluded if exposed to noncardiovascular medications or if symptoms were documented as unlikely related to exposure.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 1,091 patients in the final analysis, 195 (17.9%) received PICU intervention. One hundred fifty-seven (14.4%) received intensive hemodynamic interventions and 602 (55.2%) received intervention in general. Children less than 2 years old were less likely to receive PICU intervention (odds ratio [OR], 0.42; 95% CI, 0.20-0.86). Exposures to alpha-2 agonists (OR, 2.0; 95% CI, 1.11-3.72) and antiarrhythmics (OR, 4.26; 95% CI, 1.41-12.90) were associated with PICU intervention. In the sensitivity analysis removing atropine from the composite outcome PICU intervention, only exposures to calcium channel antagonists (OR, 2.12; 95% CI, 1.09-4.11) and antiarrhythmics (OR, 4.82; 95% CI, 1.57-14.81) were independently associated with PICU intervention. No independent association was identified between PICU intervention and gender, polypharmacy, intentionality or acuity of exposure, or the other medication classes studied.

CONCLUSIONS

PICU interventions were uncommon but were associated with exposure to antiarrhythmic medications, calcium channel antagonists, and alpha-2 agonists. As demonstrated via sensitivity analysis, exact associations may depend on institutional definitions of PICU intervention. Children less than 2 years old are less likely to require PICU interventions. In equivocal cases, age and exposure to certain cardiovascular medication classes may be useful to guide appropriate disposition.

Single-Pass Albumin Dialysis as Rescue Therapy for Pediatric Calcium Channel Blocker Overdose

Calcium channel blocker ingestions remain one of the leading causes of death related to cardiovascular medication ingestion in both adults and pediatric patients. We report a case of a 17-year-old, 103 kg female presenting after an intentional polypharmacy ingestion, including 500 to 550 mg of amlodipine. She presented with profound vasoplegia and cardiovascular collapse requiring high-dose inotropes and eventual life support with extracorporeal membrane oxygenation (ECMO). Current available treatments, designed for adults, including lipid emulsion and methylene blue, provided no sustained clinical improvement. This resulted in the initiation of single-pass albumin dialysis (SPAD). We aim to describe the clinical implications, amlodipine toxic dose effects, and clinical challenges associated with large pediatric patients and high-dose medications. We also discuss several challenges encountered related to dosing and concentration of medications, which led to fluid overload. Given the ongoing obesity epidemic, we routinely see pediatric patients of adult size. This will continue to challenge pediatric use of adult dosing and concentrations to avoid excessive fluid administration for high-dose medications, such as insulin and vasoactive agents. To our knowledge, this is the first successful case of using SPAD in conjunction with ECMO for salvage therapy after refractory life-threatening calcium channel blocker toxicity.

Management of Calcium Channel Blocker Toxicity in the Pediatric Patient

Calcium channel blockers (CCBs) are commonly prescribed cardiovascular medications used in several disease states including hypertension, coronary artery disease, and atrial fibrillation. Inadvertent exposure or intentional overdose of CCBs may result in hypotension, bradycardia, dysrhythmias, conduction disturbances, and hyperglycemia. In the most severe cases, CCB toxicity can lead to rapid cardiovascular collapse. Given the risk of significant morbidity and mortality associated with CCB toxicity, it is important that health care professionals are able to recognize and treat patients who present with a potentially toxic ingestion. Due to the paucity of literature in managing pediatric patients with severe CCB toxicity, treatment strategies for pediatric patients are mostly limited to case reports and extrapolation from expert consensus recommendations for adults. All pediatric patients with a potentially toxic CCB ingestion should be evaluated in the emergency department. Activated charcoal may be considered for asymptomatic patients presenting within an hour of ingestion. Symptomatic patients should be placed under cardiac monitoring and treatments to stabilize the patient's hemodynamics should not be delayed. Traditional first-line IV therapies include small boluses of fluids, calcium, and vasopressors. High-dose insulin has been proposed to independently increase inotropy and improve CCB-induced hypoinsulinemia and insulin resistance that results from CCB inhibition of insulin release from pancreatic β-islet cells. High-dose insulin is recommended as first-line therapy for adults and shows promising efficacy and safety in several pediatric case reports. Intravenous lipid emulsion may be considered in patients who are refractory to first-line therapies, although the data for pediatric patients are extremely limited.

Are vasopressors useful in toxin-induced cardiogenic shock?

OBJECTIVE

Overdoses with cardio-depressive medications can result in toxin-induced cardiogenic shock (TICS), a life-threatening condition characterized by severe hypotension and ineffective tissue perfusion. Vasopressors are often employed in the treatment of shock to increase heart rate and blood pressure. We sought to conduct a systematic review of the literature to evaluate the effectiveness of vasopressors in improving hemodynamic function and survival in the treatment of TICS.

DATA SOURCES

We searched PubMed, EMBASE, TOXLINE, and International Pharmaceutical Abstracts.

STUDY SELECTION

We included studies evaluating the use of vasopressors in humans or animals with TICS. We limited human study types to randomized controlled trials, clinical trials, observational studies, and case reports.

DATA EXTRACTION

Our search yielded 913 citations and 144 of these met our inclusion criteria. 130 were human case reports and 14 were animal studies.

DATA SYNTHESIS

Human case report data showed vasopressors were ineffective more often than they were partially or fully effective. In the majority of animal studies, vasopressor treatment failed to improve hemodynamic parameters and resulted in decreased survival.

CONCLUSIONS

Human case reports and controlled animal experiments lead to different conclusions about vasopressors in TICS. Most animal studies indicate that vasopressors impair hemodynamic function and increase mortality. In contrast, human case reports suggest that vasopressors are often ineffective but not necessarily harmful.

Fatal acute intoxication of accidentally ingested nifedipine in an infant - A case report

A fatal case of acute nifedipine intoxication in a two-year-old boy is presented. The boy accidentally orally ingested an unknown amount of his grandfather's nifedipine (40mg/tablet), mistaking it for a ramune confectionery. Despite intensive medical treatment, his death was confirmed at 31h after the accidental ingestion. The forensic autopsy revealed that there were neither pathological alterations or injuries in all of the organs. Toxicologically, nifedipine could be detected at the concentrations of 0.463, 0.669 and 13.0μg/g in cardiac blood, peripheral blood and stomach contents, respectively. These concentrations were evaluated as fatal levels, and the cause of death was diagnosed as acute nifedipine intoxication. Recently, the number of infants and children who accidentally ingest drugs in the home is increasing. This case report prompts forensic pathologists and toxicologists to emphasize that children are always exposed to the risk of accidental drug ingestion in daily life.

Treatment for calcium channel blocker poisoning: a systematic review

CONTEXT

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.

[Verapamil intoxication: beware of the delayed effect]

Intoxication with calcium channel inhibitory drugs is rare but mortality rates reach 10 %. We report the case of a 5-year-old girl who had ingested five 240-mg tablets of extended-release verapamil (VLP) and a tablet of bromazepam. Thirty hours after the ingestion she had a vasoplegic shock, heart conduction disorders, and metabolic complications. She was treated in pediatric intensive care with continuous epinephrine and insulin and recovered completely 60h after the ingestion. This case underlines the danger of calcium channel blocker overdose, increased by the extended-release mechanism: the drug effect is to slow down gastric motility - which explains the latency of the symptoms - but this also increases the drug absorption, inducing a vicious circle. These mechanisms in calcium blocker intoxication need to be kept in mind in order to decrease the mortality of such accidents.

Near fatal case of amlodipine poisoning in an infant

An 11-mo-old infant received 12.5 times the maximum therapeutic dose of amlodipine as a result of a medication error in lieu of amoxicillin. He presented with vomiting, lethargy, breathlessness, muffled heart sounds and progressed to hypotensive shock within three hours of admission. He received mechanical ventilation, fluid therapy with normal saline and inotropes. But his parameters improved rapidly only after initiating him on insulin and dextrose infusion therapy (for 15 h) along with glucagon and calcium gluconate infusion (for 72 h). Calcium channel blockers (CCB) cause impaired insulin secretion causing hyperglycemia. High levels of blood sugar are of prognostic value rather than hemodynamic variables in CCB poisoning. A continuous infusion of 0.5 to 1 unit per kg body weight per hour of insulin along with supportive therapy including peritoneal dialysis (for deranged renal function) was used with success in managing amlodipine poisoning.

Calcium Channel Blocker Ingestion: An Evidence-Based Consensus Guideline for Out-of-Hospital Management

In 2003, U.S. poison control centers were consulted after 9650 ingestions of calcium channel blockers (CCBs), including 57 deaths. This represents more than one-third of the deaths reported to the American Association of Poison Control Centers' Toxic Exposure Surveillance System database that were associated with cardiovascular drugs and emphasizes the importance of developing a guideline for the out-of-hospital management of calcium channel blocker poisoning. The objective of this guideline is to assist poison center personnel in the appropriate out-of-hospital triage and initial management of patients with suspected ingestions of calcium channel blockers. An evidence-based expert consensus process was used to create this guideline. This guideline applies to ingestion of calcium channel blockers alone and is based on an assessment of current scientific and clinical information. The expert consensus panel recognizes that specific patient care decisions may be at variance with this guideline and are the prerogative of the patient and the health professionals providing care, considering all of the circumstances involved. The panel's recommendations follow. The grade of recommendation is in parentheses. 1) All patients with stated or suspected self-harm or the recipient of a potentially malicious administration of a CCB should be referred to an emergency department immediately regardless of the amount ingested (Grade D). 2) Asymptomatic patients are unlikely to develop symptoms if the interval between the ingestion and the call is greater than 6 hours for immediate-release products, 18 hours for modified-release products other than verapamil, and 24 hours for modified-release verapamil. These patients do not need referral or prolonged observation (Grade D). 3) Patients without evidence of self-harm should have further evaluation, including determination of the precise dose ingested, history of other medical conditions, and the presence of co-ingestants. Ingestion of either an amount that exceeds the usual maximum single therapeutic dose or an amount equal to or greater than the lowest reported toxic dose, whichever is lower (see Table 5), would warrant consideration of referral to an emergency department (Grade D). 4) Do not induce emesis (Grade D). 5) Consider the administration of activated charcoal orally if available and no contraindications are present. However, do not delay transportation in order to administer charcoal (Grade D). 6) For patients who merit evaluation in an emergency department, ambulance transportation is recommended because of the potential for life-threatening complications. Provide usual supportive care en route to the hospital, including intravenous fluids for hypotension. Consider use of intravenous calcium, glucagon, and epinephrine for severe hypotension during transport, if available (Grade D). 7) Depending on the specific circumstances, follow-up calls should be made to determine outcome at appropriate intervals based on the clinical judgment of the poison center staff (Grade D).

Amlodipine toxicity in children less than 6 years of age: a dose-response analysis using national poison data system data

BACKGROUND

Amlodipine is a long-acting calcium channel blocker capable of producing hypotension and dysrhythmia in overdose. The toxic doses of amlodipine in children are unclear.

OBJECTIVES

The purposes of this study were to describe amlodipine poisoning in children and to determine whether a dose-response relationship could be detected in this population using standardized call data from United States (US) poison centers.

PATIENTS AND METHODS

1251 amlodipine-only ingestions in children < 6 years of age were reviewed. Cases with doses coded as "Exact" or "Estimated" and with dose, age, and medical outcome were analyzed (n = 678). Ingestions reported as a "taste or lick" (n = 53) were included as a dose of 1/10 of the dosage form involved. A clinically important response was defined as bradycardia, hypotension, dysrhythmia, conduction disturbance, or hyperglycemia. The risk of such responses was examined over four dosage intervals (< 2.5 mg, 2.5-5 mg, 5.1-10 mg, and > 10 mg).

RESULTS

The median estimated dose ingested was 5 mg (range 0.25-200 mg). Clinically important responses developed in 27 patients (3.98%), and the prevalence of such response significantly increased from 0% for the lowest to 11.1% for the highest dose interval (p = 0.001). The smallest dose to produce a clinically important response was 2.5 mg (0.15 mg/kg). Children who ingested > 10 mg were 4.4 times more likely to develop clinically important responses than those ingesting < or = 5 mg.

CONCLUSION

Hypotension may occur in children with amlodipine doses as low as 2.5 mg. The National Poison Data System might provide useful insights regarding dose-response.

The poisoned child in the pediatric intensive care unit

Acutely poisoned children remain a common problem facing pediatricians working in acute care medicine in the United States and worldwide. The management of such children continues to be challenging, and their care has evolved throughout the years. The concept of gastric decontamination in acute poisoning has significantly changed over the past 10 years, and many of the previously used techniques have been abandoned or fallen out of favor for lack of evidence to their benefit or unacceptable serious risks and side effects. Supportive care continues to be the cornerstone in managing most poisoned children. Only a few patients benefit from antidotes or specific interventions.

Are One or Two Dangerous? Calcium Channel Blocker Exposure in Toddlers

Unintentional pediatric ingestions of calcium channel blockers are increasing in frequency due to increased use of this antihypertensive class. Potential toxic effects include severe refractory hypotension and death; however, the true toxicity of unintentional pediatric ingestions of 1-2 pills is poorly defined. A literature review was conducted to more closely determine toxic and lethal dosages of calcium channel blockers in the pediatric population under 6 years of age. Results indicate that, although most accidental pediatric ingestions are asymptomatic, a small number do result in cardiovascular instability or even death. The dihydropyridines, particularly nifedipine, and the phenylalkylamine verapamil are most often implicated in symptomatic ingestions. There are no adequate data to identify which children are predisposed to illness, or to determine cutoffs for toxic dosages. However, ingestions of only one pill have been documented to cause severe symptoms, including death. Thus, emergency evaluation to assess potential toxicity is necessary, and gastrointestinal decontamination and in-hospital observation of at least 6 h after toxic ingestion for regular release medications, and 12-24 h after toxic ingestion for sustained release medications is recommended for all cases of unintentional calcium channel blocker ingestion in children younger than 6 years of age.

Pediatric Toxicology

Pediatric patients present unique concerns in the field of medical toxicology. First, there are medicines that are potentially dangerous to small children, even when they are exposed to very small amounts. Clinicians should be wary of these drugs even when young patients present with accidental ingestions of apparently insignificant amounts. Next, over-the-counter laxatives and syrup of ipecac, although not commonly considered abused substances, may be misused in both the setting of Munchausen's syndrome by proxy and in adolescents who have eating disorders. Their use should be considered in any gastrointestinal illness of uncertain origin. Finally, as the use of syrup of ipecac at home now has been discouraged by many, some have explored using activated charcoal at home as a new method of prehospital gastrointestinal decontamination. The literature examining activated charcoal and its use in this capacity is discussed.

Deadly ingestions

More than 50% of the toxic-exposure calls to US poison centers involve children. Although most of these exposures are nontoxic, there are several products and medications that are widely available to the pediatric population that can lead to severe toxicity or even death. With some of these medications, death or severe symptoms can occur with the ingestion of only a small amount. It is important that the clinician be familiar with presenting signs and symptoms of potentially toxic ingestions and is able to initiate a therapeutic and life-saving intervention. This article reviews some of the deadlier ingestions that children may be exposed to.

Ventricular arrhythmia following short-acting nifedipine administration

Short-acting nifedipine is still advocated for use in children with severe hypertension, but is no longer recommended for use in adults because of adverse effects from rapid blood pressure reduction. A 19 year-old adolescent with symptomatic, severe hypertension (blood pressure 180/120) received 10 mg of short-acting nifedipine sublingually for blood pressure reduction. Within minutes after the dose, the patient complained of palpitations. Tachycardia (heart rate 100 beats per minute) and bigeminy were noted on the cardiac monitor. The bigeminy resolved but premature ventricular contractions were noted for the duration of her hospital stay. We hypothesize that reflex sympathetic activation following an abrupt drop in blood pressure may cause arrhythmias because of elevated catecholamine levels. Given this, it may be more appropriate to treat severe hypertension in children with intravenous antihypertensive agents that can be titrated to produce controlled reductions in blood pressure.

Deadly pediatric poisons: nine common agents that kill at low doses

More than 97% of pediatric exposures reported to the AAPCC in 2001 had either no effect or mild clinical effects. Despite the large number of exposures, only 26 of the 1074 reported fatalities occurred in children younger than age 6. These findings reflect the fact that, in contrast to adolescent or adult ingestions, pediatric ingestions are unintentional events secondary to development of exploration behaviors and the tendency to place objects in the mouth. Ingested substances typically are nontoxic or ingested in such small quantities that toxicity would not be expected. As a result, it commonly is believed that ingestion of one or two tablets by a toddler is a benign act and not expected to produce any consequential toxicity. Select agents have the potential to produce profound toxicity and death, however, despite the ingestion of only one or two tablets or sips. Although proven antidotes are a valuable resource, their value is diminished if risk after ingestion is not adequately appreciated and assessed. Future research into low-dose, high-risk exposures should be directed toward further clarification of risk, improvements in overall management strategies,and, perhaps most importantly, prevention of toxic exposure through parental education and appropriate safety legislation.

Pharmacology, Pathophysiology and Management of Calcium Channel Blocker and ??-Blocker Toxicity

Calcium channel blockers (CCB) and beta-blockers (BB) account for approximately 40% of cardiovascular drug exposures reported to the American Association of Poison Centers. However, these drugs represent >65% of deaths from cardiovascular medications. Yet, caring for patients poisoned with these medications can be extremely difficult. Severely poisoned patients may have profound bradycardia and hypotension that is refractory to standard medications used for circulatory support.Calcium plays a pivotal role in cardiovascular function. The flow of calcium across cell membranes is necessary for cardiac automaticity, conduction and contraction, as well as maintenance of vascular tone. Through differing mechanisms, CCB and BB interfere with calcium fluxes across cell membranes. CCB directly block calcium flow through L-type calcium channels found in the heart, vasculature and pancreas, whereas BB decrease calcium flow by modifying the channels via second messenger systems. Interruption of calcium fluxes leads to decreased intracellular calcium producing cardiovascular dysfunction that, in the most severe situations, results in cardiovascular collapse.Although, CCB and BB have different mechanisms of action, their physiological and toxic effects are similar. However, differences exist between these drug classes and between drugs in each class. Diltiazem and especially verapamil tend to produce the most hypotension, bradycardia, conduction disturbances and deaths of the CCB. Nifedipine and other dihydropyridines are generally less lethal and tend to produce sinus tachycardia instead of bradycardia with fewer conduction disturbances.BB have a wider array of properties influencing their toxicity compared with CCB. BB possessing membrane stabilising activity are associated with the largest proportion of fatalities from BB overdose. Sotalol overdoses, in addition to bradycardia and hypotension, can cause torsade de pointes. Although BB and CCB poisoning can present in a similar fashion with hypotension and bradycardia, CCB toxicity is often associated with significant hyperglycaemia and acidosis because of complex metabolic derangements related to these medications. Despite differences, treatment of poisoning is nearly identical for BB and CCB, with some additional considerations given to specific BB. Initial management of critically ill patients consists of supporting airway, breathing and circulation. However, maintenance of adequate circulation in poisoned patients often requires a multitude of simultaneous therapies including intravenous fluids, vasopressors, calcium, glucagon, phosphodiesterase inhibitors, high-dose insulin, a relatively new therapy, and mechanical devices. This article provides a detailed review of the pharmacology, pathophysiology, clinical presentation and treatment strategies for CCB and BB overdoses.

Life-threatening isradipine poisoning in a child

Calcium channel blockers as a group are responsible for significant morbidity and mortality with toxic exposures. Isradipine, a cardioselective dihydropyridine calcium channel blocker, rarely has been implicated, with only two reports in the literature of significant toxic reactions, one in an adult and another in a child. To our knowledge, we describe the first case of life-threatening isradipine poisoning in a child and provide documentation of serum drug levels. On arrival at the hospital, a 5-year-old girl had abdominal distention and bradycardia that rapidly progressed to asystole. She received 73 minutes of cardiopulmonary resuscitation and transvenous cardiac pacing and survived with an intact neurologic recovery. Serum concentrations of isradipine were 30-100 times those found with therapeutic use.

Pediatric toxicologic concerns

Pediatric poisonings account for significant morbidity in the United States each year. Clinicians must keep current with advances in toxicology to be familiar with the latest recommended treatment regimens and antidotes. They also must be familiar in identifying toxidromes and important physical examination findings. Having these skills can enable the clinician to determine who is at risk for significant morbidity or mortality and to provide the appropriate medical care.