N-acetyl cysteine in the management of rodenticide consumption - life saving?

Liver Transplantation Society of India Guidelines for the Management of Acute Liver Injury Secondary to Yellow Phosphorus-Containing Rodenticide Poisoning Using the Modified Delphi Technique of Consensus Development

BACKGROUND

Acute liver failure caused by the ingestion of yellow phosphorus-containing rodenticide has been increasing in incidence over the last decade and is a common indication for emergency liver transplantation in Southern and Western India and other countries. Clear guidelines for its management are necessary, given its unpredictable course, potential for rapid deterioration and variation in clinical practice.

METHODS

A modified Delphi approach was used for developing consensus guidelines under the aegis of the Liver Transplantation Society of India. A detailed review of the published literature was performed. Recommendations for three areas of clinical practice, assessment and initial management, intensive care unit (ICU) management and liver transplantation, were developed.

RESULTS

The expert panel consisted of 16 clinicians, 3 nonclinical specialists and 5 senior advisory members from 11 centres. Thirty-one recommendations with regard to criteria for hospital admission and discharge, role of medical therapies, ICU management, evidence for extracorporeal therapies such as renal replacement therapy and therapeutic plasma exchange, early predictors of need for liver transplantation and perioperative care were developed based on published evidence and combined clinical experience.

CONCLUSION

Development of these guidelines should help standardise care for patients with yellow phosphorus poisoning and identify areas for collaborative research.

Human Zinc Phosphide Exposure in Lebanon: A Case Report and Review of the Literature

Introduction

Toxicity from rodenticides such as metal phosphides is common worldwide, particularly in developing countries where consumers have access to unlabeled and uncontrolled insecticides and pesticides.

Case Report

We present the first documentation of a metal phosphide exposure in Lebanon. A middle-aged woman presented to the emergency department following the ingestion of an unknown rodenticide. Spectroscopy analysis of the sample brought by the patient was used and helped identify zinc phosphide. The patient developed mild gastrointestinal symptoms and was admitted to the intensive care unit for observation without further complications.

Review

We subsequently conducted a literature review to understand the diagnosis, pathophysiology, clinical presentation, and management of metal phosphide toxicity. Multiple searches were conducted on MEDLINE and PubMed, and articles related to the topics under discussion were included in the review. Metal phosphide is associated with significant morbidity and mortality involving all body systems. Patients presenting with metal phosphide intoxication need extensive workup including blood testing, electrocardiogram, and chest radiography. To date there is no antidote for metal phosphide toxicity, and management is mostly supportive. Many treatment modalities have been investigated to improve outcomes in patients presenting with metal phosphide toxicities.

Conclusion

Emergency physicians and toxicologists in developing countries need to consider zinc and aluminum phosphides on their differential when dealing with unlabeled rodenticide ingestion. Treatment is mostly supportive with close monitoring for sick patients. Further research is needed to better understand metal phosphide toxicity and to develop better treatment options.

Role of therapeutic plasma exchange in acute liver failure due to yellow phosphorus poisoning

BACKGROUND

Therapeutic plasma exchange (TPE) has been utilized in various liver disorders. There is limited data on the efficacy of TPE in patients with acute liver failure (ALF).

METHODS

Study group consisted of patients who underwent TPE for ALF due to yellow phosphorous poisoning (YPP) between 2015 and 2019. Demographic data and biochemical parameters were recorded before and after TPE. Overall survival and transplant-free survival (based on King's College Hospital Criteria [KCHC]) were analyzed.

RESULTS

Forty-three patients underwent TPE for ALF due to YPP. Most of them were young males. Overall survival was 34 (79.06%). In our study population, 20 patients fulfilled KCHC (Group A) and 23 did not fulfill KCHC (Group B). Both the groups showed significant improvement in alanine aminotransferase, aspartate aminotransferase, and international normalized ratio (INR) after TPE (p < 0.05). In Group B, there was significant improvement in ammonia after TPE (p < 0.05) and all 23 patients (100%) survived after TPE. In Group A, 4 underwent liver transplantation (LT), 7 survived without LT, and the remaining 9 died without LT. Mean survival after completing TPE was 41.2 ± 44.5 days in Group A and 90 days in Group B. This difference was statistically significant (p = 0.001). There was statistically significant difference in post-TPE values of INR (p = 0.012) and ammonia (p = 0.011) between non-survivors and survivors. Adverse events such as hypotension (11.62%) and minor allergic reaction (4.65%) were managed conservatively.

CONCLUSION

TPE is an effective procedure in ALF due to YPP, not fulfilling KCHC for LT. In KCHC fulfilled group, though it shows LT-free survival benefit, there is requirement of prospective, large volume, multi-center study to assess its efficacy.

Rodenticide Poisoning

How to cite this article: D'Silva C, Krishna B. Rodenticide Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S272–S277.

COMPROMISED FERTILITY IN FREE FEEDING OF WILD-CAUGHT NORWAY RATS (RATTUS NORVEGICUS) WITH A LIQUID BAIT CONTAINING 4-VINYLCYCLOHEXENE DIEPOXIDE AND TRIPTOLIDE

Wild rat pests in the environment cause crop and property damage and carry disease. Traditional methods of reducing populations of these pests involve poisons that can cause accidental exposures in other animals and humans. Fertility management with nonlethal chemicals would be an improved method of rat pest population control. Two chemicals known to target ovarian function in female rats are 4-vinylcyclohexene diepoxide (VCD) and triptolide. Additionally, triptolide impairs spermatogenesis in males. A liquid bait containing no active ingredients (control), or containing triptolide (0.001%) and VCD (0.109%; active) was prepared to investigate the potential use of these agents for wild rat pest population control. Liquid bait was made available to male (n = 8 control; n = 8 active) and female (n = 8 control; n = 8 active) Sprague Dawley rats ( Rattus norvegicus ) for oral consumption prior to breeding. Whereas, control bait-treated females produced normal-sized litters (10.0 ± 1.7 pups/litter), treated females delivered no pups. Wild Norway male (n = 20) and female (n = 20) rats ( Rattus norvegicus ) were trapped, individually housed, and one group given free access to control bait, one group to active bait. Following three cycles of treatment-matched mating pairs, females consuming control bait (control) produced normal litter sizes (9.73 ± 0.73 pups/litter). Females who had consumed active bait (treated) produced no litters on breeding cycles one and two; however, 2 of 10 females produced small litters on the third mating cycle. In a fourth breeding cycle, control females were crossmated with treated males, and treated females were crossmated with control males. In both groups, some dams produced litters, while others did not. The differences in response reflect a heterogeneity in return to cyclicity between females. These results suggest a potential approach to integrated pest management by compromising fertility, and could provide a novel alternative to traditional poisons for reducing populations of wild rat pests.