Introduction
Organophosphorus Compound (OPC) pesticide intoxication is estimated at 3 million per year worldwide with approximately 300,000 deaths mostly in Asia pacific region. Severe organophosphorus pesticides poisoning is a major clinical problem in Bangladesh.
Objectives
To assess the short term outcome OPC poisoning based on Peradeniya Organophosphorus Poisoning Scale (POP) soon after hospital admission into DMCH.
Study design
We evaluated the usefulness of the severity scale and Glasgow coma score by observational study for predicting the outcome.
Place of study
Medicine Ward of Dhaka Medical College Hospital, Dhaka.
Duration of study
July 2010 to December 2010.
Study materials
Study population - All patients with Acute OPC poisoning admitted in Medicine ward of Dhaka Medical College Hospital, Dhaka.
Study methods
Suspected cases of OPC poisoning were enrolled and observed for at least 96 hours. Detailed history and clinical manifestations of all enrolled cases were taken in a pre-design case record form. All admitted cases were treated with traditional antidote of atropine and pralidoxime and other supportive treatment also given.
Results
Fifty patients of OPC poisoning who attended in the medicine ward who fulfilled the inclusion criteria were enrolled in the study. 88% of study patients were used OPC for deliberate self harm and 12% were accidental. Common clinical presentation were Pupillary (90%), Vomiting (80%), Bradycardia (52%), Abdominal cramp (42%), Tachypnea (34%), Salivation (32%) and Altered consciousness (30%) and Fasciculation (8%) respectively. 64% patients got recovered completely, 12% recovered with minor symptoms, 16% died and 8% remained in life threatening condition. In our study, according to POP scale, 62.50% were fatal and only 11.76% patients were survived among the severe graded patients. In moderate grade, non fatal cases were 64.70% and fatal cases were 37.50%. No fatal case was detected in mild grade of POP scale.
Conclusion
In our study 16% patients died. It is one of the commonest causes of death in medicine ward. The POP scale appears useful in assessing the severity of poisoning in term of management plan. The patients with evidence of moderate and severe degree of poisoning need to be monitored closely.
Poisoning is a common medical emergency. Self inflicted violence accounts for around half of the 1.6 million deaths that occur every year worldwide [1]. Currently self poisoning with pesticide has become a major clinical problem of the developing countries [2,3]. Bangladesh is a developing country of South Asia. Rural Population of this country is mostly dependant on agricultural cultivations. With the advancement of times, the limited availability of cultivating land results in widespread use of insecticides such as Organophosphorus Compound (OPC) [4] and these are readily available as Over the Counter (OTC) drugs in village shops and act as a common agent for suicidal purpose after trivial family problems [5]. Industrialized countries are also affected by it, where a significant proportion of suicidal deaths are caused by pesticide ingestion [6,7].
Organophosphorus Compound (OPC) intoxication is estimated at 3 million per year worldwide with approximately 300,000 deaths largely in Asia pacific region [8]. Fatality rate following deliberate ingestion of op pesticides in developing country in Asia is approximately 20% and may reach 70% during certain seasons and at rural hospitals [9]. According to annual report 2009, Department of Medicine DMCH, Bangladesh, it shown that about 18% of total poisoning patient are organophosphorus pesticides poisoning [10].
The basic mechanism of toxic effect of organophosphorus compound is the inhibition of acetyl cholinesterase at the nerve ending resulting accumulation of excess acetylcholine [4]. Most patient die from cardio respiratory failure [11].
A number of systems have been proposed for predicting outcome in Organophosphorus Compound (OPC) poisoning. Many are reliant on laboratory tests [12-16] and are, therefore, less useful in resource poor locations. Others that use clinical parameters have only been validated using small numbers of patients.
The Peradeniya Organophosphorus Poisoning (POP) scale assesses the severity of the poisoning based on the symptoms at presentation and is simple to use. In a study by Senayeke et al., patients with a high score on the POP scale had a high rate of morbidity and mortality [17].
This study used to investigate whether it was possible to predict inpatient mortality in organophosphorus poisoning using a scoring system based on simple clinical parameters recorded only at admission. This might enable clinicians to identify patients at high risk of dying soon after presentation, allowing more intensive monitoring and treatment. A simple system based on clinical features is likely to be most useful in low income countries where the majority of organophosphorus poisoning occurs [18].
There is no universal consensus regarding diagnosis, grading of severity and management of this serious life threatening poisoning [19]. Different individualized spectrum of management is available around the world. The supportive and specific antidote are given and tuned according to individual patient. Psychological assessment and prevention strategies are lacking, ICU setup and logistic supports for proper management are also not available in all health facilities.
From this hospital based study the purpose was to see if this POP scale could predict mortality in organophosphorus pesticides poisoning using data collect prospectively on a patient's admission in Dhaka Medical College Hospital in Bangladesh.
The degree of severity is dependent on the degree of inhibition of synaptic cholinesterase, which can be indirectly assessed by serum cholinesterase activity [20]. The most serious manifestations and the usual cause of death are respiratory failure results from weakness of respiratory muscles and depression of the respiratory centre, aggravated by excessive bronchial secretion and bronchospasm.
Miosis is one of the most characteristic signs and is found in almost all patients of moderately severe and severely poisoning. Miosis may persist even after death. Transient hyperglycemia and glycosuria are found in severe OPC poisoning.
The Peradeniya Organophosphorus Poisoning (POP) scale [17], which is based on five cardinal manifestations of OPC poisoning (miosis, fasciculation, respiratory difficulty, bradycardia and impairment of consciousness), can be used to assess the severity OPC poisoning at bed side immediately after admission (Table 1).
1. MiosisPupil size > 2mmPupil size ≤ 2mmPupil pin point | 012 |
2. FasciculationNonePresent but no generalized or continuousGeneralized and continuous | 012 |
3. RespirationRespiratory rate ≤ 20/minRespiratory rate > 20/minRespiratory rate > 20/min with cyanosis | 012 |
4. BradycardiaPulse rate > 60/minPulse rate 41 - 60/minPulse rate ≤ 40/min | 012 |
5. Level of consciousnessConscious & rationalImpaired, responds to verbal commandImpaired, no response to verbal command | 012 |
(If convulsion present add 1) | 1 |
Total | 11 |
Mild | 0-3 |
Moderate | 4-7 |
Severe | 8-11 |
Table 1: Peradeniya Organophosphorus Poisoning (POP) scale.
The study was carried out in the Medicine Ward of Dhaka Medical College Hospital, Dhaka from July 2010 to December 2010. Our objectives were to predict the outcome OPC poisoning based on clinical parameters soon after hospital admission, to assess the severity of poisoning, to describe the outcome of OPC poisoning of hospital admitted patient.
All patients had a history of organophosphorus pesticide ingestion as stated by the patient or relatives, the transferring doctor or the pesticide bottle. Any cases with suspected OPC poisoning with clinical manifestations. Those patients were excluded who refused to give consent voluntarily and patients who had taken more than one poison were excluded. Purposive type non probability sampling technique was used in the study.
All data was collected by using a performed data sheet, this was done by detailed history from patient relatives, complete physical examination. Short term outcome of all the cases was recorded. Statistical analysis was done by SPSS. Results presented by choosing of variables in the form of tables, graph, percentage, chart etc. The frequency rates of various information were described & compared using statistical methods.
Organophosphorus compounds are widely used in agricultural and industrial area and as a domestic insecticide agent. It is the leading cause of morbidity and mortality due to poisoning specially agriculture based developing country like Bangladesh. In our study 16% patients died. Early diagnosis and treatment is essential to reduce the mortality and morbidity from this lethal compound. Resources for laboratory estimation of blood cholinesterase and organophosphorus level are not available in most area of developing countries. POP scale appears to be very useful to assess the severity of OPC poisoning in our study, as in severe grade showing more fatality than in mild grade. In moderate grade of POP scale also shows significant fatality. So patients with moderate and severe grade of POP scale need close monitoring to reduce the mortality.
Citation: Ahasan HAMN, Faruk AA, Bala CS, Minnat B (2017) Predicting the Short Term Outcome in Acute Organophosphorus Compound (OPC) Poisoning with Poison Severity Scale on Hospital Admission in Dhaka Medical College Hospital. J Toxicol Cur Res 1: 002.
Copyright: © 2017 Ahasan HAMN, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.