Outcome of Rodenticide Poisoning and Its Associated Factors Among Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, North Central Ethiopia

Introduction

Poisoning is a major global public health issue, and occurrences are growing due to changes in lifestyle and social behavior. According to the World Health Organization (WHO), unintentional poisoning resulted in 106,683 deaths and the loss of 6.3 million years of healthy life worldwide (disability adjusted life years, DALYs).^1,2 Rodenticides are pesticides that are used to kill rodents. Because they destroy insects, they are also used as a grain preservative. It is a broad term that covers a vast range of compounds. The drugs’ chemical makeup, mode of action, hazardous dosages, and lethal impact differ. It is categorized according to whether the agent is anticoagulant or non-anticoagulant. They are commonly used as self-harm and suicide agents in several parts of the poor world.³

Rodenticide poisoning causes severe symptoms involving several essential organs, which is lethal. They are among the most toxic substances regularly found in homes. The varieties of rodenticides used over the years are legion.⁴

According to the American Association of Poison Control Centers (AAPCC), rodenticides are responsible for 75,514 cases, 66,362 of which are unintentional and 1598 of which are intentional, with 29 persons dying as a result.⁵

Despite the fact that rodenticide poisoning is a major public health risk in Africa, only ten of 58 nations (17.2%) have poisons information centers (PICs).⁶

In Ethiopia, there is a scarcity of epidemiological data on the consequences of rodenticide poisoning. According to a study conducted in central Ethiopia, poisoning is the most common agent for self-poisoning and is associated with significant mortality.⁷

There are only two studies done on the outcome of rodenticide poisoning in Ethiopia, so the current study is intended to assess outcome and associated factors among adult patients admitted with rodenticide poisoning at the emergency unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022.

Methods

Study Design and Study Period

Institutional-based cross-sectional study was used. The data were collected from June 1 through June 30, 2022.

Study Area

Debre Tabor Comprehensive Specialized Hospital was founded in 1923 E.C. in Debre Tabor Town. Debre Tabor is the capital city of South Gondar Zone; it is 666 kilometers from Addis Ababa and 103 kilometers from Bahir Dar, the capital city of Amhara Regional State. DTCSH has provided preventative, delivery, and curative health services to about 2.7 million people in the Zone and surrounding regions. It contains around 275 inpatient beds in six disciplines, three laboratory sites, five emergency OPDs, and more than 12 outpatient departments (OPDs). Debre Tabor University also uses it as a teaching hospital. Every year, around 8000 emergency patients are seen at the emergency department.

Source Population

During the study period, all rodenticide-poisoned adult patients were included, whereas patients with inadequate medical records and patients who took rodenticide mixed with other poisons were excluded. This study included the records/charts of all patients who came in medical emergency DTCSH with rodenticide poisoning in the specified study period.

Variables of the Study

The dependent variable in the study was patient outcome after rodenticide poisoning, while the independent variables were socio-demographic variable, time of arrival, mode of poison, admission status, referral status, mode of hospital arrival, co-morbidities, length of stay, treatment given, blood pressure, and pulse rate at admission. A data abstraction sheet was constructed using information from patients’ medical records and was adapted from several sources.^8–11

Operational Definition

Good outcome: Refers when the physician declared the status improved (recovered) at discharge, transfer out to higher institution, against medical advice.

Poor outcome: Refers when the physician declared death summary or survived with disability.

Recovered: When the rodenticide poisoned patient was discharged without disability.

Disability: Either physical or psychological disability leading to a new morbidity, dialysis, respiratory, or another organ failure, following rodenticide poisoning, which was confirmed by laboratory investigation or suspected by clinicians, based on the clinical complaints of patients.

Data Collection Procedure and Tool

After retrieving the patient card from the card store using the medical record number and cross-referencing it with the registration book, the essential information was recorded using a structured checklist format. The cases were chosen if and only if they met the inclusion criteria. The sampling procedure of this study was census method with included all patients presented with rodenticide poisoning. The data abstraction format was created in English and included variables such as sex of patients, age of patients, residence, route of poisoning, mode of poisoning, clinical presentations, the status of patients when they arrived at the hospital, reason of patients for taking the poison, time of arrival to the hospital’s emergency department, length of hospital stay, treatment given for rodenticide poisoning, and outcome. Data were collected from the records by two well-trained BSc nurses.

Data Quality Control

The pre-test on 5% of total study population were conducted in DTCSH. Any errors discovered throughout the pretesting process were corrected, and changes were made to the final version of the data abstraction format. As data collectors, two BSc nurses were assigned. One day of training was provided on the goal of the study, the structured checklist, and ensuring the confidentiality of the charts to the data collectors. The data was supervised by a competent supervisor to ensure its completeness and consistency. During and after data collection, all acquired data was checked for completeness and consistency.

Data Analysis

The data was entered into EPI data version 4.6, then exported and analyzed using STATA version 14 software. Frequency tables, text, and figure were used to present the data. The association of factors with the outcome was investigated using bivariable and multivariable analysis. If the p-value was less than 0.25, variables were transferred from bivariable to multivariable. The strength of the statistical link was quantified using the odds ratio and 95% confidence intervals, and statistical significance was determined using p-values of 0.05.

Results

Socio-Demographic Characteristics

The study included 156 adult patients admitted to Debre Tabor Comprehensive Specialized Hospital (DTCSH) with rodenticide poisoning from May 1, 2017 to April 30, 2022. One hundred fifty-six (156) patient’s medical records had complete information and were included in the final analysis making the response rate 100%. The majority, 86 (55.13%) were in the age group of 20–40 years. The median age of patients was found to be 23 with IQR of (19, 30.5) years. More than half, 83 (53.21%), were females. The majority, 131 (83.97%), of the admitted patients were from rural residence (Table 1).

Table 1 Socio-Demographic Characteristics of Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (N = 156)

Baseline Information of the Patients

Three-fourth of the cases were related to suicidal poisoning. Commonly reported reason for taking the poison was quarrel with family members, which accounts for 46 (36.8%). Two-third, 102 (65.38%), clients arrived at the hospital by public transport (Table 2).

Table 2 Base Line Information of the Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (N = 156)

Clinical Characteristics

At the time of admission, 123 (78.85%) of the adult patients were conscious, and 113 (72.44%) were normotensive.

More than half of the cases, 90 (57.69%), arrived within two hours. Only 27 (17.37%) of the cases had comorbidities. Complications such as psychiatric illness, dyspepsia, acute respiratory distress syndrome, acute renal failure, and electrolyte imbalance occurred in more than half of the cases, 89 (57.05%). All of the poisoning routes were ingestion and non-anticoagulant in type (Table 3).

Table 3 Clinical Characteristics of Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (N = 156)

Treatment Given

Based on the patient’s case, the client received both pharmacological and non-pharmacological care for rodenticide poisoning. Gastric lavage was used as a non-pharmacologic treatment to prevent hazardous substance absorption in 90 (57.69%) of the cases. Metoclopramide 148 (94.87%), cimetidine 146 (93.59%), and magnesium sulphate 116 (74.36%) were the most commonly used pharmacologic treatments (Table 4).

Table 4 Treatment Given for Adult Patients Admitted with Rodenticide Poisoning at the Emergency Unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (n = 156)

Patient Outcome

Among 156 records of adult patients with the diagnosis of rodenticide poisoning included in the study, 77 (49.56%) had poor outcome, from those who had poor outcome (43.8%) were died and 5.76% were survived with disability (Figure 1).

Figure 1 Treatment outcome of adult patients admitted with rodenticide poisoning at the emergency units of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (n = 156).

Factors Associated with Poor Treatment Outcome of Rodenticide Poisoning

Both bi-variable and multivariable logistic regression were undertaken. In the multivariable analysis, age, residence, mode of poisoning, referral status, admission status, blood pressure at admission, pulse rate, and length of hospital stay were fitted for multivariable analysis. However, in bi-variable analysis, only modes of poisoning, referral status and pulse rate were significantly associated with poor outcomes of rodenticide poisoning. Patients with suicidal poisoning were 10.64 times more likely to have poor outcome than those with accidental poisoning (AOR = 10.64; 95% CI: 2.43, 46.53). Patients who referred from other health facility were 5.78 times more likely to have poor outcome than self-referred (AOR = 5.78; 95% CI: 1.97, 16.95). Patient with tachycardia at admission were 5.41 times more likely to have poor outcome than those with normal pulse rate (AOR = 5.41; 95% CI: 1.54, 18.98) (Table 5).

Table 5 Bivariable and Multivariable Logistic Regression Analysis of Factors Associated with Poor Outcome of Rodenticide Poisoning Outcome for Adult Patients at the Emergency Unit of DTCSH, Debre Tabor, North Central Ethiopia, 2022 (n = 156)

Discussion

The purpose of this research was to assess the treatment outcome of rodenticide poisoning and its associated factors in adult patients admitted to the DTCSH emergency unit. According to this study, the overall magnitude of poor outcome in rodenticide poisoning was 49.56% (95% CI) (41.5, 57.2). This finding was reinforced by investigations in Morocco and Egypt, which reported a death rate of 49% and 45.5%, respectively.^12,13 However, a study conducted at Felege Hiwot Referral Hospital Bahir Dar and Tehran-Iran found a lower mortality rate of 31.2% and 24.06%, respectively.^4,14 This disparity could be attributed to differences in study period, study population, medication availability, and both studies explain that most of the tablets were exposed to air or expired tablets, which have lower phosphide content due to gradual release of phosphine gas.

However, when we compared this prevalence to a comparable study done on 418 patients by Chugh et al, the overall mortality from rodenticide poisoning was 77.2%, 58.9% Nehru Hospital Chandigarh in Northwest India, and 61% in Hospital Avicenna, Rabat.^15–17 This variation can be attributed to differences in sample size, study population, study area, study design, dose eaten, time of arrival, kind of poisoning, and vomiting, which accounts for 94.87% of the total in our study because vomiting boosts the survival rate.¹⁸ Other factors, such as financial background, cultural differences (traditional versus medical counsel), and religious beliefs, may contribute to those results outside of Ethiopia.

Suicidal poisoning patients were 10.64 times more likely to have a poor outcome than accidental poisoning patients (AOR = 10.64; 95% CI: 2.43, 46.53). The finding was supported by research conducted in eastern Ethiopia.¹⁹ The explanation for this could be because if a person consumes the poison for suicide reasons, they may swallow it all because it is intended to kill them.

Patients referred from another health facility were 5.78 times more likely than non-referred patients to have a poor outcome (AOR = 5.78; 95% CI: 1.97, 16.95). This could be attributed to a late presentation to the hospital beginning with poison intake, as well as a lack of ambulances or facilities in that rural health center.

Patients who had tachycardia at the time of admission were 5.41 times more likely to have a poor outcome than those who had a normal pulse rate (AOR = 5.41; 95% CI: 1.54, 18.98). This was also the conclusion of an Egyptian study.^13,20 This is because rodenticide poisoning disrupts electrolytes, resulting in cardiac arrhythmia and cardiogenic shock. Hypotension, on the other hand, will cause tachycardia as a compensatory strategy. As a result, most common cause of mortality in rodenticide poisoning was cardiac arrest.

Limitation of the Study

Use of cross-sectional study was the limitation. Because of financial scarcity, we used cross-sectional study; it was better if we used cohort study.

Conclusions

Rodenticide poisoning had a bad overall outcome. Suicidal poisoning, having tachycardia, and being referred from another health center all contributed to poor rodenticide poisoning outcomes. As a recommendation, the health care providers should better organize to generate information on the mortality of rodenticide poisoning and suicidal act. Health care providers and institutions should maintain counseling and family-centered services that allow adults to develop coping mechanisms and pay special attention to the vital signs of rodenticide-poisoned patients.