Successful reversal of life threatening cardiac effect following dosulepin overdose using intravenous lipid emulsion

Effect of lipid emulsion on neuropsychiatric drug-induced toxicity: A narrative review

Lipid emulsion has been shown to effectively relieve refractory cardiovascular collapse resulting from toxic levels of nonlocal anesthetics. The goal of this study was to examine the effect of lipid emulsions on neuropsychiatric drug-induced toxicity using relevant case reports of human patients, with a particular focus on the Glasgow Coma Scale (GCS) score and corrected QT interval, to analyze drugs that frequently require lipid emulsion treatment. The following keywords were used to retrieve relevant case reports from PubMed: "antidepressant or antipsychotic drug or amitriptyline or bupropion or citalopram or desipramine or dosulepin or dothiepin or doxepin or escitalopram or fluoxetine or haloperidol or olanzapine or phenothiazine or quetiapine or risperidone or trazodone" and "lipid emulsion or Intralipid." Lipid emulsion treatment reversed the corrected QT interval prolongation and decreases in Glasgow Coma Scale scores caused by toxic doses of neuropsychiatric drugs, especially lipid-soluble drugs such as amitriptyline, trazodone, quetiapine, lamotrigine, and citalopram. The log P (octanol/water partition coefficient) of the group which required more than 3 lipid emulsion treatments was higher than that that of the group which required less than 3 lipid emulsion treatments. The main rationale to administer lipid emulsion as an adjuvant was as follows: hemodynamic depression intractable to supportive treatment (88.3%) > lipophilic drugs (8.3%) > suspected overdose or no spontaneous breathing (1.6%). Adjuvant lipid emulsion treatment contributed to the recovery of 98.30% of patients with neuropsychiatric drug-induced toxicity. However, further analyses using many case reports are needed to clarify the effects of lipid emulsion resuscitation.

Literature review of the evidence regarding intravenous lipid administration in drug-induced cardiotoxicity

Introduction: Intravenous lipid emulsion (ILE) administration is capable of reversing the acute cardiac and neurological toxicity caused by local anesthetic agents. In recent years, ILE has also been explored as a potential antidote for cardiotoxicity caused by non-anesthetic agents too. Areas covered: The potential mechanisms, safety, and efficacy of this approach are considered. Data were sought from published reports listed in PubMed and EMBASE, and abstracts of meetings of the North American Congress of Clinical Toxicology and European Association of Poisons Centres and Clinical Toxicologists. There were reports involving 298 patients where ILE has been administered for severe drug toxicity. Clinical improvement was observed in 57 of 59 patients with local anesthetic toxicity (96.6%); there were 239 patients where toxicity was due to non-anesthetic agents, and ILE apparently improved clinical outcome in 215 (72.1%). Expert opinion: Response rates were similar between ILE treated toxicity caused by lipid soluble and non-lipid soluble drugs. Potential adverse effects of ILE include interference with laboratory assays, acute pancreatitis, and adult respiratory distress syndrome, although the rate of occurrence is difficult to ascertain.

Intravenous Lipid Emulsion as Antidote: Experience in Hong Kong

Objective

Intravenous lipid emulsion (ILE) is an emerging therapy in the field of toxicology. The purpose of this study was to report the accumulated local experience on using ILE in the management of patients suffering from poisoning by pharmaceutical agents other than local anaesthetics.

Design

Case series.

Setting

Local poison information centre.

Methods

Ten patients were identified from the database of Hong Kong Poison Information Centre. The patients were managed in 6 Hong Kong public hospitals during a 4-year study period (July 2008-June 2012).

Results

Nine of them presented with drug-induced cardiotoxicity, defined as either cardiac arrest (n=3) or hypotension refractory to other treatments (n=6). The overall survival rate is 30%. Possible adverse events from ILE included mild derangement of liver function, elevated amylase and hyperlipidaemia were observed.

Conclusions

About 30% of severe poison-induced cardiotoxicity treated with ILE can survive with no major adverse effects. The use of ILE remains to be a treatment option for lipid-soluble drug induced severe toxicity not responsive to standard resuscitation measures. (Hong Kong j. emerg.med. 2015;22:100-107)

A cohort study of unstable overdose patients treated with intravenous lipid emulsion therapy

Objectives

Intravenous lipid emulsion (ILE) has been used increasingly over the last decade for a range of drug overdoses. Although the use of ILE in local anesthetic toxicity (LAST) is well established, the hemodynamic effectiveness of ILE in non-LAST poisonings is still unclear. Thus, the primary objective of this study was to examine a cohort of poisoned patients in whom ILE was administered.

Methods

Consecutive patients were identified by calls to a regional poison center from May 1, 2012 to May 30, 2014. Patients were enrolled if they ingested a drug, developed hemodynamic instability, failed conventional treatment, and received ILE therapy. Data were collected by medical record review. The primary outcome was the change in mean arterial pressure (MAP) in the first hour after ILE administration. Secondary outcomes included survival, length of stay, and the effect of drug class on patient outcome.

Results

Thirty-six patients were enrolled. Agents ingested included calcium channel blockers and beta blockers (10/36, 27.8%), tricyclic antidepressants (5/36, 13.9%), bupropion (3/36, 8.3%), and antiepileptic agents (1/36, 2.8%). Seventeen patients (47.2%) ingested multiple agents. Twenty-five patients survived (69.0%). Overall, MAP increased by 13.79 mm Hg (95% CI 1.43–26.15); this did not meet oura prioridefinition of clinical significance.

Conclusions

Our study did not find a clinically important improvement in MAP after ILE administration. Until future research is done to more definitively study its efficacy, ILE should remain a potential treatment option for hemodynamically unstable overdose patients only after conventional therapy has failed.

Tricyclic antidepressant overdose treated with adjunctive lipid rescue and plasmapheresis

Tricyclic antidepressant poisoning remains a major cause of morbidity and mortality, particularly in the setting of suicidal attempts. The current standard of care for treatment is the administration of sodium bicarbonate infusion. Adjunctive lipid emulsion therapy and plasmapheresis have received attention recently. We report an 18-year-old patient who was successfully managed with lipid emulsion and plasmapheresis as adjuncts to sodium bicarbonate treatment and review some of the recent literature.

Hypersensitivity reactions to intravenous lipid emulsion in swine: relevance for lipid resuscitation studies

BACKGROUND

Reports in the recent experimental literature have provided contradicting results in different animal species regarding the efficacy of IV lipid emulsion (ILE) in the reversal of cardiovascular and central nervous system symptoms of local anesthetic and other lipophilic drug overdoses. In particular, ILE seemed to be effective in rats, rabbits, dogs, and humans, but not in swine, for which it not only failed to reverse the adverse effects of anesthetics, but the animals also developed a generalized cutaneous mottling or a dusky appearance immediately after ILE, suggestive of another type of toxicity. The latter symptoms arise in complement (C) activation-related pseudoallergy, a hypersensitivity reaction to particulate drugs and agents.

METHODS

Ten Yorkshire swine (15-20 kg) were sedated with ketamine and anesthetized with isoflurane. ILE 1.5 and 5 mL/kg 20% was administered via the ear vein while pulmonary arterial pressure, systemic arterial blood pressure, electrocardiogram, and end-tidal CO2 were recorded continuously. Thromboxane was measured in blood collected at baseline and 2 and 10 minutes after injections. Complement activation by lipid emulsion was also assessed in vitro with soluble terminal complement complex (SC5b-9) and sheep red blood cell assays.

RESULTS

Significant increases were observed in the pulmonary pressure (median [interquartile range]) within minutes after the administration of ILE, both at doses 1.5 and 5 mL/kg (15 [12-16.5] to 18.5 [16-20] mm Hg, P = 0.0058 and 15.5 [13-17.25] to 39.5 [30.5-48.5], respectively). The systemic arterial blood pressure increased, and the heart rate decreased after both injections. Thromboxane B2 concentration (median [interquartile range]) in the blood plasma increased from a baseline of 617.3 [412.4-920] to 1132 [597.9-1417] pg/mL (P = 0.0055) and from 1276 [1200-2581] to 4046 [2946-8442] pg/mL (P = 0.0017) after the administration of 1.5 and 5 mL/kg ILE, respectively. Intralipid did not cause in vitro complement activation in human serum.

CONCLUSIONS

ILE causes clinically significant hemodynamic changes in pigs, in concert with significant increases in the plasma thromboxane concentration. However, the in vitro tests did not confirm involvement of the complement system in human sera, leaving the underlying mechanism of these findings in doubt. Nonetheless, the observed hemodynamic and biochemical effects of ILE serve as a caveat that the pig is not an ideal model for the study of interventions involving ILE.

Should we consider the infusion of lipid emulsion in the resuscitation of poisoned patients?

The use of intravenous lipid emulsions (ILEs) as antidote in local anaesthetic systemic toxicity has gained widespread support following convincing data from animal models, and successful case reports in humans. Proposed beneficial mechanisms of action for ILEs include intravascular sequestration of intoxicant and subsequent enhanced redistribution to biologically inert tissues, augmentation of fatty acid utilisation for ATP synthesis in the context of metabolic poisoning, and direct cardiotonic and ion channel effects. The evidence base for use of ILEs in acute drug intoxication is evolving. The present evidence supports use of ILEs only in local anaesthetic systemic toxicity and in lipophilic cardiotoxin intoxication when there is an immediate threat to life, and other therapies have proven ineffective.

Review of the use of lipid emulsion in nonlocal anesthetic poisoning

Intravenous lipid emulsion (ILE) has been used widely for the treatment of poisoning due to local anesthetic agent and is increasingly reported as a therapy for other forms of poisoning. This article will review the proposed mechanisms of action for ILE in poisoning and the evidence from animal studies and human experience supporting the use of ILE for poisoning due to nonlocal anesthetic agents.

Effect of intravenous lipid emulsion in patients with acute glyphosate intoxication

BACKGROUND

Although glyphosate intoxication has been considered minimally toxic in animals, severe toxicity has been observed in humans due to surfactant. We aimed to examine the potential therapeutic effects of intravenous lipid emulsion (ILE) on the patients with acute glyphosate intoxication.

METHODS

This study enrolled 64 glyphosate-intoxicated patients with allocation to two groups: those treated with ILE (ILE group, n = 22), and control patients treated with only supportive (conservative) care. Control patients were selected by matching for the amount ingested and time since ingestion. Twenty-two control patients were separately selected from the 42 patients receiving supportive care only. In ILE group, 20% lipid emulsion product was injected intravenously at the rate of 20 mL/h for the patients who ingested less than 100 ml of glyphosate. In the patients who ingested more than 100 ml of glyphosate, the loading dose was 500 ml for 2-3 h according to the status of the patients, followed by a maintenance dose of 1000 ml for the next 24 h.

RESULTS

Thirteen patients received high dose of ILE because the ingestion amount was more than 100 ml. None of the ILE group suffered from the complication of hypotension, while approximately 41% of the control group developed the complication. Additionally, arrhythmia was not observed in the ILE group. The incidence of mental change, respiratory failure, and acute kidney injury was similar between the two groups.

CONCLUSIONS

ILE administration was associated with lower incidence of hypotension and arrhythmia in patients with acute glyphosate intoxication. ILE administration seems to be an effective treatment modality in patients who ingested sufficient amount of glyphosate herbicide that is expected to bring about significant toxicity.

Intravenous lipid administration for drug-induced toxicity: a critical review of the existing data

Following the discovery that administration of intravenous lipid emulsion (ILE) may reverse the cardiac and neurological toxicity of certain local anesthetic agents, ILE's potential role has recently been explored in the setting of toxicity attributed to a variety of different drugs. The potential mechanisms, safety and efficacy of this approach are considered in this review. Data are reviewed from 76 published reports involving ILE administration for severe drug toxicity, including 55 where toxicity was due to nonanesthetic agents. ILE was reported to exert a positive therapeutic effect in only a proportion of the reported cases, with greatest evidence of efficacy concerning local anesthetic agents. Administration has typically involved bolus administration followed by continuous maintenance infusion, and a number of different mechanisms are proposed, from preferential partitioning of the drug from cardiac tissue to the circulating lipid fraction and direct inotropic effects related to carnitine pathways and fatty acid oxidative metabolism. No major adverse effects have been encountered, but too few data exist to adequately address the safety profile of ILE.

Use of intravenous lipid emulsions for treating certain poisoning cases in small animals

Intravenous lipid emulsion (ILE) infusions have become an emerging treatment modality in managing intoxications of veterinary patients. The advantages of ILE include an apparent wide margin of safety, relatively low cost, long shelf-life, and ease of administration. Based on limited case and anecdotal reports, ILEs have shown promise in the management of toxicoses from a variety of lipophilic agents, including drugs and pesticides. More studies are needed to determine optimum dosing regimens and identify potential adverse effects from the antidotal use of ILE in veterinary medicine.