Hamida Jamil ( Department of Medicine, Jinnah Postgraduate Medical Centre, Karachi. )
A review of nineteen hundred cases of acute poisoning admitted to the Intensive Care Unit shows that poisoning was responsible for 40% of the emergencies treated at this Unit, between 15th January, 1976 to 15th November, 1985. Comparing our data with Western figures, it was noted that the pattern of poisoning in our Country is considerably different from that in the West. Organophosphorus Insecticide Poisoning was by far the commonest in our series and was responsible for the majority of fatal cases. Over-all mortality rate for all the other poisons excluding Organophosphorus Insecticide compared favourably with Western figures, being 1.8% (JPMA 40:131, 1990).
Acute poisoning forms an important and major group of emergencies treated in the department of Intensive Care at the Jinnah Postgraduate Medical Centre, Karachi and was responsible for 1900 of the 4738 patients treated in the unit over a ten year period. The pattern of poisoning in our country differs from that in the Western Countries. In our Country Organophosphozus Insecticides1 take the lead by a great majority, in the west it is the tranquilisers, hypnotics and sedatives which are most frequently used in self poisoning. The pattern of poisoning has an important bearing on management and prognosis. Whereas most of the cases of self-poisoning can be treated without resorting to the use of specialized forms of treatment such as artificial ventilation; OPI poisoning cases more often required such treatment. Moreover, the over mortality rate from OPI poisoning was much higher than that from all other poisons. The Intensive Care Unit at Jinnah Postgraduate Medical Centre which has now been made a poison control and reference centre, consists of an Intensive therapy Section .of eight beds and a Progressive Patient Care Unit of sixteen beds. The treatment facilities in the unit consist of Cardiac monitoring, defibrillation and artificial ventilation. On the investigative side beside routine investigations, facilities for blood gases analysis and examination of poison levels have been made available recently.
MATERIAL AND METHODS
Nineteen hundred cases were included in this study. Most of them were initially assessed in the casualty department where gastric lavage and induced emesis were given when indicated, in addition to other resuscitative measures. The patients were brought to the casualty department by relatives, friends and the police or were referred by the family physicians. Detailed clinical data were recorded and they were classified into three groups suicidal, accidental and homicidal.
Analysis of the data of 1900 cases is presented here.
Age/sex and Marital Status
Most of our cases i.e. 1466 (77%) were between the ages of 11-30 years. There were one thousand and three (52.8%) females and eight hundred and ninety seven (47.2%) males. Of the females, 66% were married and 34% unmarried; whereas, of the male, 74% were unmarried and 26% were married. It is intresting to note that the majority of cases occured in married females and unmarried males.
62% of our cases belonged to the low income group and 38% to the average and high income group. Studying the pattern of poisoning in different socio-economic groups, it is noted that the majority of patients in the low income group (95.6%) used Organophosphorus insecticides; whereas, the majority (72%) in the high income group resorted to tranquilisers, sedatives and hypnotics as a mode of poisoning. 525 (58.5%) of the males were educated, whereas 233 (23%) of the females were professionals. Accidental poisoning as an occupational hazard occured in 3% of our cases, most of whom were fumigators or porters, handling insecticides.
Reasons for taking the Poison
70% of the cases were suicidal or parasuicidal, 21.5% accidental and 1.8% homicidal. Of the suicidal cases 1305 were first attempts and 25 had made more than one attempt. 15% of these cases were under psychiatric treatment and 3% were suffering from an associated organic disease.
Table II shows that the frequency and the type of poisons taken by our patients. By far the commonest poisoning encountered was that of Organophosphorus insecticides followed by tranquilisers mainly ben¬zodiazepines, sedatives and hypnotics including opiates, and antidepressants (Tricycic group).
Table III gives a comparative study of our figures with those of Western Countries. When we compare our figures with those from Western series, we note that hardly any cases of Organophosphorus Insecticide Poisoning have been reported in these studies, where the lead is taken by sedatives, hypnotics and tranquilisers followed by an¬tidepressants, salicylates and alcohol.
State of Consciousness on Arrival
At the time of admission 85% of the patients were unconscious and 15% conscious. Of the former 56% were in grade-I, 183% in grade-II, 12.5% in grade-Ill, and 13% in grade-N coma.
Diagnosis was based on the history, as given by the relatives or the patients after recovery in 95% cases, characteristic clinical pattern of poisoning in 60%, naked eye examination of stomach contents in 10% of cases, drug prescriptions or bottles and containers brought by the relative in 7.6% of cases. Cholinesterase levels were done in a few of the cases of Organophosphorus Insecticide Poisoning.
Clinical Pattern of Common Poisons encountered (Table IV)
The typical clinical features of parasympathetic over activity are very characteristics of Organophosphorus Insecticide Poisoning. This can be confirmed by resistance to atropinisation by a therapeutic dose of Injection Atropine and low serum Cholinesterase levels.
General management of these cases is shown in Table V.
Immediately the patient is received by us, an attempt is made to empty the stomach by emesis, or gastric lavage when the patient is unconscious or emesis contraindicated. In order to enhance elimination of the poison we have done forced alkaline diuresis in cases of phenobar¬bitone and salicylate poisoning with good results. Specific antidotes were given immediately when indicated (Table VI).
Out of the total of 1900 cases 1793 (94.4%) recovered, 107(5.6%) expired. Of those 107 who expired the majority 72(3.8%) were cases of Organophosphorus Insecticide. A significantly higher mortality rate is seen in cases of Organophosphorus Insecticide Poisoning. Of the 1793 patients who recovered 1216 (70%) were referred to the neuro-psychiatry out-patients department, 200 (11.15%) were referred to the social workers, 41 (2.3%) were transferred to the neuropsychiatry ward and 296(16.5%) were discharged without referral.
The pattern of poisoning in our country is very different to that in the West. Organophosphorus Insecticide form a major proposition of cases admitted with acute poisoning and their incidence has increased at an alarming rate from 34% in 1979 to 48% in 1981 to 63% in 1985. The mortality rate of Organophosphorus Insecticide Poisoning though significantly reduced than in our earlier studies, is still twice as high as that from other poisons. In our experience intensive care alone is sufficient in the management of most cases of acute poisoning. In view of the increased incidence of Organophos-phorus Insecticide Poisoning, its higher mortality rate and the greater need for sophisticated and expensive ventilatory support, restriction on the sale of insecticides may reduce the frequency of poisoning.
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