Recovery of cyclic antidepressants with gastric lavage

Is there a Role for Hemoperfusion/Hemodialysis as a Treatment Option in Severe Tricyclic Antidepressant Intoxication?

Objective

Suicidal self-poisoning with tricyclic antidepressants like doxepin is a major therapeutic problem in emergency medicine with a high fatality rate. Deaths are mainly caused by cardiotoxicity with arrhythmias, intraventricular conduction disturbances and myocardial depression. For treatment, alkalinization and hypertonic saline are recommended. The role of extracorporeal treatment procedures is not clear. The possible benefit of hemoperfusion/hemodialysis is discussed in a case report with respect to the published literature.

Case Report

After ingestion of an amount of at least 5000 mg doxepin a 37-year-old man with endogenous depression developed cardiac arrest. After preclinical resuscitation with prolonged external cardiac massage, he was admitted to the intensive care unit with persistently severe hypotension and wide QRS complexes (230–260 ms). Despite fluid load, alkalinization, hypertonic saline and high-dose vasoactive substances the patient's condition did not improve. Hemoperfusion over hemoresin combined with hemodialysis led to an impressive clinical improvement with shortening of QRS duration (from 230 to 120 ms) and hemodynamic stabilization. The patient fully recovered without neurologic deficits.

Conclusion

We report a successful treatment with hemoperfusion over hemoresin and hemodialysis in a patient with life-threatening doxepin poisoning intractable with the generally recommended treatment. In such acute TCA intoxication with severe cardiotoxicity, hemoperfusion/hemodialysis should be considered a potential treatment option, as the “toxicokinetics” of drugs may totally differ from their usual pharmacokinetic behaviour. Experimental and clinical studies are needed to clarify the toxicokinetics of TCA in order to improve the therapeutic approach.

Cyclic Antidepressant Poisoning: A Review and Case Report

Although newer cyclic antidepressants have been introduced over the past several years, the tricyclic antidepressants (TCAs) continue to be the leading cause of morbidity from drug overdose in the United States. Overdose features depend on the particular cyclic antidepressant ingested and its pharmacological properties, and can include CNS depression, cardiac arrhythmias, hypotension, seizures, and anticholinergic symptomatology. Life-threatening symptomatology almost always begins within 2 hours, and certainly within 6 hours, after arrival to the emergency department. Plasma TCA levels are unreliable predictors of TCA toxicity and are not recommended. An ECG with a prolonged QRS complex more than 100 msec seems to be the best indicator of serious sequelae with TCAs. Management consists of stabilization of vital signs, gastrointestinal decontamination, intravenous sodium bicarbonate, and supportive care. Agents once thought to be useful for the treatment of cardiac dysrhythmias and seizures such as phenytoin and physostigmine should be avoided. The future of TCA antibody fragments in the treatment of TCA overdose seems promising. Newer and, to some degree, safer antidepressants in overdose have recently been introduced, and they include fluoxetine, trazodone, and sertraline. Amoxapine, bupropion, and maprotiline seem to be as toxic as the TCAs. A significant interaction between cyclic antidepressants and monoamine-oxidase inhibitors exists. Management includes supportive care and basic poison management. Prevention of poisoning seems to be the most logical and effective method of maintaining patient safety. TCAs should be avoided in children younger than 6 years old. All adults with suicidal ideations should receive no more than a 1-week supply (about 1 g) of drug. Finally consideration should be given to using one of the newer, safer antidepressants in all patients with suicidal ideations.

Suicide attempts by deliberate self-poisoning in children and adolescents

AIM

The objective of the study was to examine the toxicological characteristics of suicide attempts by deliberate self-poisoning in children and adolescents.

METHOD

From the Toxicological Information Centre's database, the inquiries due to the suicide attempts in children (9-13 years old) and adolescents (14-18 years old) were evaluated.

RESULTS AND CONCLUSIONS

From 10,492 calls concerning suicide attempts, 2393 concerned children and adolescents. Most suicide attempts were attempted in spring (31.3%). Among the toxic agents, drugs were used in 97.8% cases. The most frequent ingestions appeared using drugs affecting the nervous system and anti-inflammatory non-steroids. The dose was evaluated as toxic in 73.4%, severely toxic in 3.0% and unknown in 11.2% cases. Only one in 10 children used a non-toxic dose. Girls, more frequently than boys (13.2% vs. 8.9%), used non-toxic doses. The symptoms of moderate and severe intoxications were present in 10.5% of the cases. Poison centre consultation was accessed within the first hour after the ingestion in one-fifth of the patients. In both age groups, the severity of the intoxication was greater among elder males who reached the medical facilities later than 4 h after the poisoning. The combinations of three or more drugs affecting central nervous system were present in the most severe cases.

Efficacy of abdominal computed tomography and nasogastric tube in acute poisoning patients

Abdominal computed tomography aids in the evaluation of the conditions in the stomach and will decrease needless gastric lavage in acute poisoning patients. A 16-year-old girl with a history of schizophrenia with depressive disorder was taken to our hospital. Her Glasgow Coma Scale was 8. Symptoms related to anticholinergic effects were strongly present. Her electrocardiogram showed sinus tachycardia with 60 milliseconds of QRS duration. Computed tomography images showed that the patient had a large amount of debris derived from tablets in her stomach and duodenum. We performed gastric aspiration through a nasogastric tube and not gastric lavage, and it took 5 minutes to complete the procedure. We administered activated charcoal 3 times. Intubation was not performed. Other than tonic-clonic seizure that was observed once, neither cardiovascular nor neurologic symptoms were observed. She recovered fully and admitted that she had ingested more than a hundred tablets almost 10 hours before being brought to our hospital. Computed tomography images show a cluster of tablets and debris to be of a higher density than tissues; this allows quantitative and qualitative evaluations to be performed. We were able to treat the patient with effective use of nasogastric tube.

Gastrointestinal decontamination of the poisoned patient

Gastrointestinal decontamination has been a historically accepted modality in the emergency management of oral intoxicants. Theoretically, gastric and whole-bowel emptying procedures hinder absorption, remove toxic substances, prevent clinical deterioration, and hasten recovery. This article presents a current overview of gastrointestinal decontamination. It challenges the accepted precepts of gut decontamination and assesses the utility of syrup of ipecac-induced emesis, orogastric lavage, single-dose-activated charcoal, cathartics, and whole-bowel irrigation.

Position paper: gastric lavage

Gastric lavage should not be employed routinely, if ever, in the management of poisoned patients. In experimental studies, the amount of marker removed by gastric lavage was highly variable and diminished with time. The results of clinical outcome studies in overdose patients are weighed heavily on the side of showing a lack of beneficial effect. Serious risks of the procedure include hypoxia, dysrhythmias, laryngospasm, perforation of the GI tract or pharynx, fluid and electrolyte abnormalities, and aspiration pneumonitis. Contraindications include loss of protective airway reflexes (unless the patient is first intubated tracheally), ingestion of a strong acid or alkali, ingestion of a hydrocarbon with a high aspiration potential, or risk of GI hemorrhage due to an underlying medical or surgical condition. A review of the 1997 Gastric Lavage Position Statement revealed no new evidence that would require a revision of the conclusions of the Statement.

The Management of Tricyclic Antidepressant Poisoning

Although there have been descriptive, uncontrolled clinical reports of removal of tablet debris by gastric lavage, there have been no clinical studies that have demonstrated that this has any impact on outcome in patients with tricyclic antidepressant (TCA) poisoning. There is also the possibility that lavage may increase drug absorption by pushing tablets into the small intestine. Furthermore, gastric lavage in patients with TCA poisoning may induce hypoxia and a tachycardia potentially increasing the risk of severe complications such as arrhythmias and convulsions. In view of the paucity of evidence that gastric lavage removes a significant amount of drug and the risk of complications associated with the procedure, the routine use of gastric lavage in the management of patients with TCA poisoning is not appropriate. Volunteer studies have shown generally that activated charcoal is more likely to reduce drug absorption if it is administered within 1 hour of drug ingestion. In the one volunteer study that looked at later administration of activated charcoal, there was a 37% decrease in plasma concentration associated with administration of activated charcoal at 2 hours post-ingestion. There have been no clinical studies that enable an estimate of the effect of activated charcoal administration on outcome in the management of patients with TCA poisoning. Volunteer studies have shown that multiple-dose activated charcoal increases the elimination of therapeutic doses of amitriptyline and nortriptyline, but not of doxepin or imipramine; however, these studies cannot be directly extrapolated to the management of patients with TCA poisoning. There have been no well designed controlled studies that have assessed the impact of multiple-dose activated charcoal in the management of patients with TCA poisoning. Because of the large volume of distribution of TCAs, it would not be expected that their elimination would be significantly increased by multiple-dose activated charcoal.Haemoperfusion, haemodialysis and the combination of these procedures do not result in significant removal of TCAs and are not recommended in the management of patients with TCA poisoning.

Extracorporeal therapies for acute intoxications

Intoxications frequently perturb acid-base and electrolyte status, intravascular volume, and renal function. In selected cases, extracorporeal techniques effectively restore homeostasis and augment intoxicant removal. The use of 4-methylpyrazole, an inhibitor of alcohol dehydrogenase, is a new and effective treatment for patients exposed to toxic alcohols. In this section, practical approaches to commonly encountered intoxicants and the use of extracorporeal techniques are critically reviewed.

Tricyclic antidepressant overdose: a review

Overdoses of tricyclic antidepressants are among the commonest causes of drug poisoning seen in accident and emergency departments. This review discusses the pharmacokinetics, clinical presentation and treatment of tricyclic overdose.

Position statement: gastric lavage. American Academy of Clinical Toxicology; European Association of Poisons Centres and Clinical Toxicologists

In preparing this Position Statement, all relevant scientific literature was identified and reviewed critically by acknowledged experts using agreed criteria. Well-conducted clinical and experimental studies were given precedence over anecdotal case reports and abstracts were not usually considered. A draft Position Statement was then produced and subjected to detailed peer review by an international group of clinical toxicologists chosen by the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists. The Position Statement went through multiple drafts before being approved by the boards of the two societies and being endorsed by other societies. The Position Statement includes a summary statement for ease of use and is supported by detailed documentation which describes the scientific evidence on which the Statement is based. Gastric lavage should not be employed routinely in the management of poisoned patients. In experimental studies, the amount of marker removed by gastric lavage was highly variable and diminished with time. There is no certain evidence that its use improves clinical outcome and it may cause significant morbidity. Gastric lavage should not be considered unless a patient has ingested a potentially life-threatening amount of a poison and the procedure can be undertaken within 60 minutes of ingestion. Even then, clinical benefit has not been confirmed in controlled studies. Unless a patient is intubated, gastric lavage is contraindicated if airway protective reflexes are lost. It is also contraindicated if a hydrocarbon with high aspiration potential or corrosive substance has been ingested.

Antidepressant Poisoning and Treatment: A Review and Case Illustration

Although newer antidepressants have been introduced over the past several years, the tricyclic antidepressants (TCAs) continue to be a leading cause of morbidity from drug overdose in the United States. Overdose features depend on the particular cyclic antidepressant ingested and its pharmacological properties, and can include CNS depression, cardiac dysrhythmias, hypotension, seizures, and anticholinergic symptoms. Life-threatening events almost always begin within two hours, and certainly within six hours, after arrival to the emergency department. Plasma TCA levels are unreliable predictors of TCA toxicity and are therefore not recommended. An ECG with a prolonged QRS complex more than 100 msec seems to be the best indicator of serious sequelae with TCA overdose. Management consists of stabilization of vital signs, gastrointestinal decontamination, intravenous sodium bicarbonate, and supportive care. Agents once thought to be useful for the treatment of cardiac dysrhythmias and seizures such as phenytoin and physostigmine should be avoided. The future of TCA antibody fragments in the treatment of TCA overdose seems promising. Amoxapine, bupropion, and maprotiline seems to be as toxic as the TCAs. Overdose data is limited for venlafaxine, and mirtazapine, and preclude firm conclusions. A significant interaction between cyclic antidepressants and monoamine-oxidase inhibitors exists. Management includes supportive care and basic poison management. Prevention of poisoning seems to be the most logical and effective method of maintaining patient safety. TCAs should be avoided in children younger than 6 years old. All adults with suicidal ideations should receive no more than a one-week supply (less than 1 g) of drug. Newer and, to some degree, safer antidepressants in overdose have recently been introduced, and they include fluoxetine, sertraline, paroxetine, trazodone, and nefazodone. Finally, consideration should be given to using one of these newer, safer antidepressants in all patients with suicidal ideations.

How safe are schools?

Images

Comparison of three methods of gut decontamination in tricyclic antidepressant overdose

The purpose of this study was to prospectively compare the effectiveness of three different gut decontamination methods in 51 patients presenting to an emergency department with tricyclic antidepressant overdose. Patients were randomized to three treatments; Group 1 received activated charcoal, Group 2 received saline lavage followed by activated charcoal, and Group 3 received activated charcoal followed by saline lavage followed by activated charcoal. Baseline characteristics of the three groups did not differ, including Glasgow Coma Scores, age, and mean tricyclic antidepressant levels. Average length of stay in admitted patients was 93.3 hours in Group 1, 107.2 hours in Group 2, and 66.7 hours in Group 3. Of those admitted to an ICU, average ICU time was 66.9 hours in Group 1, 54.1 hours in Group 2, and 34.4 hours in Group 3. Average duration of sinus tachycardia was 20.8 hours in Group 1, 30.8 hours in Group 2, and 32.2 hours in Group 3. Of those requiring mechanical ventilation, average ventilator time was 43.4 hours in Group 1, 24.1 hours in Group 2, and 17.8 hours in Group 3. No statistically significant difference could be shown with respect to the clinical endpoints noted. There were no deaths in any of the groups. All three methods of gut decontamination had similar clinical outcomes.

Successful treatment of amoxapine-induced refractory status epilepticus with propofol (diprivan)

Tonic-clonic seizure activity is a recognized complication of amoxapine overdose. Refractory drug-induced status epilepticus is associated with significant morbidity and mortality. Standard regimens for controlling status epilepticus may be ineffective for aborting drug-induced seizures. The authors report the case of a 30-year-old woman who presented with an amoxapine overdose that deteriorated into status epilepticus refractory to conventional therapy. Propofol given by intravenous bolus and maintenance infusion successfully halted the patient's seizure activity. This case suggests that propofol may be effective as an anticonvulsant in refractory drug-induced status epilepticus.

Cyclic antidepressant overdose: a review of current management strategies

Cyclic antidepressant (CA) overdose can produce life-threatening seizures, hypotension, and dysrhythmias. It accounts for up to half of all overdose-related adult intensive care unit admissions and is the leading cause of death from drug overdose in patients arriving at the emergency department alive. Several factors contribute to the significant morbidity and mortality associated with CA overdose. First, CAs are widely prescribed and are dispensed to patients at increased risk for attempting suicide. Second, drugs of this class generally have a low therapeutic toxic ratio. Third, in the majority of fatal cases, the patient dies before reaching a hospital. Finally, and of greatest significance for the clinician, the presenting signs and symptoms of CA overdose may be missed by the physician, even in cases of severe toxicity. Therefore, CAs must be considered early in any case of suspected overdose, and all such cases should be managed as potentially fatal ones. The following case demonstrates the current approach to the patient with significant CA toxicity.

Update in medical toxicology

This article examines some current issues in toxicologic care. First there is a review of the scope of pediatric poisonings and some aspects of initial management. Then there is a discussion of the decision-making process required to properly use gastric decontamination in the management of poisonings. Each of the common methods available--emesis, gastric lavage, activated charcoal, catharsis, and whole bowel irrigation--is discussed. Finally, several new and old antidotes are reviewed, namely naloxone, glucagon, bicarbonate, dimercaptosuccinic acid, digoxin-specific fab fragments, and flumazenil.

Tricyclic antidepressant poisoning

OBJECTIVE

To review poisoning with tricyclic antidepressants.

DATA SOURCE

English language literature search using Australian Medlars Service (1977-1989), manual search of journals and review of bibliographies in identified articles.

STUDY SELECTION

Approximately 250 articles, abstracts and book chapters were selected for analysis.

DATA EXTRACTION

The literature was reviewed and 93 articles were selected as representative of important advances.

DATA SYNTHESIS

The major features of overdose are neurological, cardiac, respiratory and anticholinergic. Life-threatening complications develop within six hours of overdose or not at all. All patients seen within six hours of overdose should have their stomachs emptied. All patients should receive activated charcoal. Coma, convulsions, respiratory depression and hypotension are treated with standard resuscitation techniques and drugs. Treat patients with significant cardiotoxicity or cardiac arrest with alkalinisation by sodium bicarbonate or hyperventilation, aiming for an arterial pH of 7.45-7.55. Lignocaine is used for ventricular arrhythmias. Other antiarrhythmic drugs are contraindicated (Class 1A, Class 1C), potentially lethal (Class II), of no benefit (phenytoin) or of unproven efficacy (Class III and Class IV). Physostigmine has no role at all. Haemodialysis and haemoperfusion are of no benefit.

CONCLUSION

The death rate of those who reach hospital is 2%-3%. Most of these deaths are cardiac in origin, and are caused by direct depression of myocardial function rather than cardiac arrhythmias.

Prospective evaluation of gastric emptying in the self-poisoned patient

The authors prospectively studied the effect of gastric emptying (GE) and activated charcoal (AC) upon clinical outcome in acutely self-poisoned patients. Presumed overdose patients (n = 808) were treated using an alternate day protocol based on a 10-question cognitive function examination and presenting vital sign parameters. Asymptomatic patients (n = 451) did not receive GE. AC was administered to asymptomatic patients only on even days. GE in the remaining symptomatic patients (n = 357) was performed only on even days. On emptying days, alert patients had ipecac-induced emesis while obtunded patients received gastric lavage. AC therapy followed gastric emptying. On nonemptying days, symptomatic patients were treated only with AC. No clinical deterioration occurred in the asymptomatic patients treated without GE. AC use did not alter outcome measures in asymptomatic patients. GE procedures in symptomatic patients did not significantly alter the length of stay in the emergency department, mean length of time intubated, or mean length of stay in the intensive care unit. Gastric lavage was associated with a higher prevalence of medical intensive care unit admissions (P = .0001) and aspiration pneumonia (P = .0001). The data support the management of selected acute overdose patients without GE and fail to show a benefit from AC in asymptomatic overdose patients.