Treatment of severe tricyclic antidepressant overdose with extracorporeal sorbent detoxification

The BioLogic-DT™ and the Saga of Liver Dialysis™

Our small R&D company created a novel extracorporeal system for the treatment of hepatic coma and drug overdose, in which membrane motion in a screen-plate dialyzer served as a blood pump and also mixed dialysate containing powdered carbon. Early clinical trials of the Biologic-DT™ were successful in the treatment of patients with hepatic coma (especially from A-on-C liver failure) and FDA gave marketing approval. The BioLogic-DT™ was licensed to a venture capital-backed startup. It was marketed too widely and used in some patients without a chance for recovery or transplant. The licensing company failed, and the BioLogic-DT was not remarketed. The MARS™ device included albumin as a sorbent in dialysate, and clinical trials of this device also showed a benefit in the treatment of hepatic coma.

Treatment of amitriptyline intoxications by extended high cut-off dialysis

Antidepressants, especially amitriptyline, are among the most frequent drug classes involved in intoxications. Despite its small molecular weight, amitriptyline is not considered to be eliminated by extracorporeal treatment methods due to its high protein binding and large volume of distribution. New high cut-off dialysers have so far not been used for removal of amitriptyline. We report two cases of amitriptyline poisoning in which we measured the amitriptyline elimination using extended high cut-off (HCO) dialysis. Despite dialyser clearances of 33 and 58 mL/min, resulting in the reduction of initial serum concentrations by ∼30%, only 211 and 920 µg of amitryptilin, respectively, (<3% of the ingested amount) could be recovered in the total collected dialysate. Hence, due to the high volume of distribution of amitriptyline, even HCO dialysis does not contribute substantially to the extracorporeal removal of amitryptilin.

Extracorporeal treatment for carbamazepine poisoning: systematic review and recommendations from the EXTRIP workgroup

Context. The Extracorporeal Treatments in Poisoning (EXTRIP) workgroup was created to provide evidence and consensus-based recommendations on the use of extracorporeal treatments (ECTRs) in poisoning. Objectives. To perform a systematic review and provide clinical recommendations for ECTR in carbamazepine poisoning. Methods. After a systematic literature search, the subgroup extracted the data and summarized the findings following a pre-determined format. The entire workgroup voted via a two-round modified Delphi method to reach a consensus on voting statements, using a RAND/UCLA Appropriateness Method to quantify disagreement. Anonymous votes were compiled, returned, and discussed in person. A second vote determined the final recommendations. Results. Seventy-four articles met inclusion criteria. Articles included case reports, case series, descriptive cohorts, pharmacokinetic studies, and in-vitro studies; two poor-quality observational studies were identified, yielding a very low quality of evidence for all recommendations. Data on 173 patients, including 6 fatalities, were reviewed. The workgroup concluded that carbamazepine is moderately dialyzable and made the following recommendations: ECTR is suggested in severe carbamazepine poisoning (2D). ECTR is recommended if multiple seizures occur and are refractory to treatment (1D), or if life-threatening dysrhythmias occur (1D). ECTR is suggested if prolonged coma or respiratory depression requiring mechanical ventilation are present (2D) or if significant toxicity persists, particularly when carbamazepine concentrations rise or remain elevated, despite using multiple-dose activated charcoal (MDAC) and supportive measures (2D). ECTR should be continued until clinical improvement is apparent (1D) or the serum carbamazepine concentration is below 10 mg/L (42 the μ in μmol/L looks weird.) (2D). Intermittent hemodialysis is the preferred ECTR (1D), but both intermittent hemoperfusion (1D) or continuous renal replacement therapies (3D) are alternatives if hemodialysis is not available. MDAC therapy should be continued during ECTR (1D). Conclusion. Despite the low quality of the available clinical evidence and the high protein binding capacity of carbamazepine, the workgroup suggested extracorporeal removal in cases of severe carbamazepine poisoning.

Extracorporeal treatment for tricyclic antidepressant poisoning: recommendations from the EXTRIP Workgroup

The Extracorporeal Treatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatments (ECTR) in poisoning. Here, the workgroup presents its results for tricyclic antidepressants (TCAs). After an extensive literature search, using a predefined methodology, the subgroup responsible for this poison reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND/UCLA Appropriateness Method to quantify disagreement. Blinded votes were compiled, returned, and discussed in person at a meeting. A second vote determined the final recommendations. Seventy-seven articles met inclusion criteria. Only case reports, case series, and one poor-quality observational study were identified yielding a very low quality of evidence for all recommendations. Data on 108 patients, including 12 fatalities, were abstracted. The workgroup concluded that TCAs are not dialyzable and made the following recommendation: ECTR is not recommended in severe TCA poisoning (1D). The workgroup considers that poisoned patients with TCAs are not likely to have a clinical benefit from extracorporeal removal and recommends it NOT to be used in TCA poisoning.

Hemodiafiltration: a novel approach for treating severe amitriptyline intoxication

Tricyclic antidepressant overdose is one of the most common cause of serious drug poisonings. Sometimes amitriptyline intoxication can be difficult to treat with standard treatments. At that case hemodiafiltration (HD) can be an eligible choice. We report a successful treatment of severe case using hemodiafiltration in addition to the supportive measures. Management with gastric lavage, activated charcoal, alkalinization and supportive care is the common approach and not enough for patients in deep coma. We satisfied that HD may have a beneficial role in lethal doses of amitriptyline as an additional therapy.

Blood purification in toxicology: nephrology's ugly duckling

Contrary to popular opinion, application of extracorporeal therapies for poisonings predates their use for ESRD. Despite this observation, the science of blood purification in toxicology remains desperately stagnant today. In fact, much of our current knowledge is derived from George Schreiner's 1958 review. Original publications are almost exclusively composed of case reports and case series, from which good inference is impossible. Until randomized controlled trials become available, the medical community would be well served by a group mandated to systematically review available literature, extract relevant information, provide recommendations based on current evidence, and propose research initiatives. The EXtracorporeal TReatments In Poisoning workgroup, formed by several international experts in different medical fields and represented by over 20 societies, now has this mission.

Charcoal hemoperfusion in an infant with supraventricular tachycardia and seizures secondary to amitriptyline intoxication

Tricyclic antidepressant (TCA) overdose is one of the common causes of drug poisoning and it has cardiovascular, respiratory and neurological side effects. An 18-month male infant was admitted to our pediatric emergency service due to poisoning with amitriptyline. The infant was unconscious. Tachycardia, irregular and shallow breathing, and tonic-clonic seizures were observed on physical examination. An electrocardiogram displayed a narrow complex tachycardia that was consistent with re-entrant supraventricular tachycardia (SVT). Although antiarrhythmic and anticonvulsive agents were administrated, SVT and seizures persisted. Charcoal hemoperfusion (HP) was performed for 4 hours. The infant's clinical condition has improved after the charcoal HP, seizures and SVT were not observed. It is concluded that charcoal HP can be used efficiently in patients with severe amitriptyline intoxication.

[Intoxication with a tricyclic antidepressant]

A 48-year-old woman with a major depression and treatment with doxepin was found comatose in her flat. Her son last saw her 48 h prior to being found. On arrival of the emergency physician, she presented a generalized seizure. The patient underwent endotracheal intubation and mechanical ventilation due to respiratory insufficiency and severe cyanosis. Empty packages of tablets (doxepin ca. 4000 mg and zolpidem 100 mg) were found in the flat. On hospital admission the doxepin blood concentration was 1.2 microg/ml. No life-threatening arrhythmia occurred at any time. On the advice of the poison information center, hemoperfusion was performed for extracorporeal elimination. Within several hours the doxepin blood concentration could be lowered to 0.8 microg/ml and although still above the therapeutic range the patient was extubated. However, the patient developed a generalized seizure which required re-intubation. As a consequence of the high distribution volume and re-distribution phenomena, the doxepin blood concentration had increased again to 1.2 microg/ml. Approximately 72 h later she was extubated again while the doxepin blood concentration was 0.9 microg/ml and 3 days later, the doxepin blood concentration was lowered to 0.3 microg/ml and the patient was transferred to the psychiatric ward the following day. This case report questions the efficacy of hemoperfusion during acute doxepin intoxication in the given constellation of a non-life-threatening arrhythmia.

Hemoperfusion in a child with amitriptyline intoxication

Tricyclic antidepressant overdose is one of the most common causes of serious drug poisoning in children and adults. We report a 17-month-old girl with severe amitriptyline intoxication. She was admitted to hospital because of lethargy and seizures. It was estimated that she took approximately 75 mg/kg of amitriptyline 2 h before admission. On examination she was comatose, had ventricular tachycardia and multifocal clonic seizures. Intravenous fluid, per oral activated charcoal, diazepam, lidocaine, and sodium bicarbonate infusion were given. However, there was no response to this therapy, and the patient remained in a deep coma with cardiac arrhythmias and seizures. Hemoperfusion (HP) was performed for 2 h. During this procedure, cardioversion was used six times due to ventricular fibrillation. She had a very good clinical response to HP and no complication was observed. We suggest that HP may be an effective treatment in children with severe amitriptyline intoxication.