Reversal of fetal benzodiazepine intoxication using flumazenil

Strategies for the treatment of acute benzodiazepine toxicity in a clinical setting: the role of antidotes

INTRODUCTION

Although not a potentially life-threatening poisoning, benzodiazepine (BZD) intoxication may be life-threatening in special situations/populations or those with background diseases.

AREAS COVERED

The aim of this review is to evaluate all possible treatment options available in the literature for the management of benzodiazepine poisoning with special attention to antidote administration. We conducted a literature search using PubMed, Google Scholar, EMBASE, and Cochrane central register from 1 January 1980 to 10 November 2021 using keywords 'benzodiazepine,' 'poisoning,' 'toxicity,' 'intoxication,' and 'treatment.'

EXPERT OPINION

Careful patient selection, ideally by a clinical toxicologist, may decrease the complications of flumazenil and add to its efficacy. The cost-to-benefit ratio should be considered in every single patient who is a candidate for flumazenil administration. In case a decision has been made to administer flumazenil, careful consideration of the possible contraindications is essential. We recommend slow administration of low doses of flumazenil (0.1 mg/minute) to avoid complications or withhold the administration with development of first signs of adverse effects. The main treatment of benzodiazepine toxicity is conservative with administration of activated charcoal, monitoring of the vital signs, prevention of aspiration and development of deep vein thrombosis due to prolonged immobilization, and respiratory support.

Lithium Toxicity in a Pregnant Woman

Lithium is recommended in bipolar disorder and can be accompanied by significant toxicity in pregnant women. A 25-year-old single-gestation pregnant woman (28 weeks) was referred with suspicion of lithium toxicity. Serum lithium was 2.1 meq/L. Despite conservative therapy with intravenous fluids, lithium concentration increased to 5.0 meq/L 6 hr after admission mandating an emergent haemodialysis during which foetal heart rate decreased to 90 bpm. The gynaecologist ordered termination of pregnancy while the mother was still on haemodialysis. Caesarean section was carried out, but the born baby had an apgar of 2 and died. Autopsy findings of the foetus revealed a cord blood lithium concentration of 4.8 mEq/L with no physical abnormalities. Although the foetus had the signs/symptoms of distress, continuation of haemodialysis could probably have saved it as it saved its mother's life. In lithium toxicity in a pregnant woman, it is reasonable to continue haemodialysis even with the signs and symptoms of foetal distress. In similar situations, emergency haemodialysis instead of immediate caesarean section should be considered.

Acute Poisoning During Pregnancy: Observations from the Toxicology Investigators Consortium

Acute poisonings during pregnancy pose a particular challenge to health care providers because of the potential for an immediate life threat or possible life-long implications for both the mother and fetus, including teratogenicity of the poison or its antidote. We describe recent consequential exposures among pregnant women in the USA. We identified all poisoning cases involving pregnant women that were catalogued by the medical toxicology services across the 37 sites of the Toxicology Investigators Consortium (ToxIC) Registry of the American College of Medical Toxicology between January 2010 and December 2012. Of 17,529 exposure cases reported in the ToxIC Registry, 103 (0.6 %) involved pregnant women, 80 % of whom were symptomatic and about a quarter displayed a specific toxidrome. The majority of cases (n = 53; 51.5 %) involved intentional exposures, most commonly to pharmaceutical agents, followed by unintentional pharmaceutical exposures (10 %) and withdrawal syndromes (9 %). Non-opioid analgesics were the most common class of agents encountered (31 %), followed by sedative-hypnotics/muscle relaxants (18 %), opioids (17 %), anti-convulsants (10 %), and anti-depressants (10 %). Over a third of cases involved exposure to multiple substances, and 32 % involved exposure to more than one drug class. The most commonly administered antidotes were N-acetylcysteine (23 %), sodium bicarbonate (10 %), flumazenil (4 %), and physostigmine (4 %). About half of acute poisoning cases among pregnant women presenting for emergency care involved intentional exposures, mostly with over-the-counter analgesics and psychoactive medications. Clinicians should be cognizant of the unique circumstances, maternal and fetal risks, and management principles of the acutely poisoned pregnant woman.

Environmentally oriented models and methods for the evaluation of drug × drug interaction effects

This detailed review compares known and widely used methods for drug interaction estimation, some of which now have historical significance. Pharmaceutical application has been noted as far back as several thousand years ago. Relatively late in the 20th century, however, researchers became aware that their fate and metabolism, which still remain a great challenge for environmental analysts and risk assessors. For the patient's well-being, treatment based on the mixing of drugs has to be effective and should not cause any side effects (or side effects should not have a significant impact on health and mortality). Therefore, it is important to carefully examine drugs both individually and in combinations. It should be also stated that application form/way of entering the living organism is of great importance as well as the age and the place in the trophic system of the organism in order to eliminate harmful dosages in the case of infants' accidental intoxication.

American gastroenterological association institute technical review on the use of gastrointestinal medications in pregnancy

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Institute Clinical Practice and Economics Committee. The paper was approved by the Committee on February 22, 2006 and by the AGA Institute Governing Board on April 20, 2006.

Sedation and analgesia for gastrointestinal endoscopy during pregnancy

Endoscopy during pregnancy raises the unique issue of fetal safety. Endoscopic medications comprise a significant component of fetal risks from endoscopy. Before endoscopy, the gastroenterologist or anesthesiologist should evaluate the potential fetal risks of sedation and analgesia, identify any contraindications to endoscopy, stabilize the maternal medical status as necessary, and correct maternal hypoxia or hypotension. The mother should be informed about the potential teratogenic risks of endoscopic medications during pregnancy. Patients who receive sedation and analgesia should be monitored during endoscopy by continuous electrocardiography, continuous pulse oximetry, and intermittent sphygmomanometry, as well as by the pulse and respiratory rate. General principles of sedation and analgesia during pregnancy include use of the minimal effective dose, avoidance of unnecessary medications, and preferable use of Food and Drug Administration category B medications.

The fetal safety and clinical efficacy of gastrointestinal endoscopy during pregnancy

More than 12,000 pregnant patients in the United States per annum have conditions that are normally evaluated by EGD. More than 6000 pregnant patients in the United States per annum have conditions that are normally evaluated by sigmoidoscopy or colonoscopy. About one thousand more have symptomatic choledocholithiasis during pregnancy, which is a strong indication for endoscopic sphincterotomy in nonpregnant patients. Endoscopy during pregnancy raises the unique issue of fetal safety. Endoscopic medications comprise a significant component of fetal endoscopic risks. Safety of EGD during pregnancy has been examined in a case-controlled study of 83 patients, a mailed survey of 73 patients, and 28 case reports. Safety of sigmoidoscopy during pregnancy has been examined in a case-controlled study of 46 patients, a mailed survey of 13 patients, and 10 case reports. Safety of therapeutic ERCP during pregnancy has been analyzed in studies of 23, 10, 6, and 5 patients, and in 32 case reports. These studies suggested that EGD, sigmoidoscopy, and ERCP should be performed when strongly indicated: EGD for significant upper gastrointestinal bleeding, sigmoidoscopy for nonhemorrhoidal rectal bleeding, and ERCP for symptomatic choledocholithiasis when sphincterotomy is contemplated. PEG and colonoscopy are currently considered experimental during pregnancy because of insufficient data on fetal safety. Several cases of PEG and colonoscopy were successfully performed during pregnancy. Performance of endoscopy during pregnancy should increase with further technical refinements, and greater awareness of procedure safety.

Are there teratogenic risks associated with antidotes used in the acute management of poisoned pregnant women?

OBJECTIVE

We reviewed evidence suggesting teratogenic risk associated with the use of antidotes in the acute management of poisoned pregnant women.

METHODS

Medline, Toxline, and DART/ETIC searches; references of retrieved articles, pertinent databases and textbooks were also searched.

RESULTS

There are case reports or case series of women who received antidotes for poisoning during (*) or after (+) the period of organogenesis who showed no fetal adverse effects. Some antidotes, however, have no teratogenic risk: atropine (cohort/surveillance studies)+, calcium (oral supplement: cohort study)+ and pyridoxine (Bendectin studies). Also, ethanol+, methylene blue (intra-amniotic injection but not oral) and penicillamine* can be considered teratogens but their risks in the treatment of poisonings are unknown. There is no epidemiologic study evaluating the risk of the following antidotes during pregnancy: N-acetylcysteine(*+), BAL (dimercaprol)+, black widow spider antivenin+, calcium EDTA+, crotalidae antivenin, crotalidae polyvalent immune FAB, cyanide antidote kit (amyl and sodium nitrate, sodium thiosulfate), deferoxamine(*+), digoxin immune FAB+, DMSA+, flumazenil+, fomepizole, methylene blue (IV), naloxone, physostigmine, pralidoxime+, protamine+; and parenteral pharmacologic doses of calcium+, folinic acid*, glucagon+, hydroxycobalamin, phytonadione (vitamin K), and pyridoxine.

CONCLUSIONS

Despite the limited evidence supporting the risk of antidote use during pregnancy, antidotes should be used when there is a clear maternal indication to decrease the morbidity or mortality associated with poisoning. The only exception may be penicillamine, which is a teratogen. Better antidotes exist for most poisonings that penicillamine could potentially treat. At this time, there is no known fetal indication for all antidotes. Reporting the use of an antidote during pregnancy should be encouraged, especially if used during the critical period of organogenesis.

The safety and efficacy of gastrointestinal endoscopy during pregnancy

More than 12,000 pregnant patients in the United States per year have conditions normally evaluated by esophagogastroduodenoscopy (EGD). More than 6000 pregnant patient in the United States per year have conditions normally evaluated by sigmoidoscopy or colonoscopy. Endoscopy during pregnancy raises the unique issue of fetal safety, and endoscopic medications comprise a significant component of fetal risks from endoscopy. This article analyzes the safety of endoscopic medications during pregnancy, reviews the literature on the safety of gastrointestinal endoscopy during pregnancy, proposes guidelines for endoscopic indications during pregnancy, and describes modifications of gastrointestinal endoscopy during pregnancy to increase fetal and maternal safety.