Acute poisonings : a comparative study of hospital admissions versus poison centre consultations

[摘要] ENGLISH ABSTRACT:A prospective study was conducted in 1999 to establish the incidence and natureof acute poisonings in the Cape Town / Western Cape region. This study wasbased on an analysis of Poison Centre queries and acute poisoning admissions toTygerberg Hospital over a period of 1 year (1999).Summary of findings for Hospital admissions (1010 cases):Acute poisonings were more common in adults (83%) than in children (17%) anddrug overdose was by far the most common clinical entity in adult Hospitaladmissions (89% of cases). Most overdoses in adults were intentional (97%).Seventy five percent of these cases were female, predominantly in the 20-40 yearage group. The incidence of non-drug chemical exposures in adults was relativelylow (11%). In children, on the other hand, there was much less of a discrepancybetween drug and non-drug chemical exposures (41% and 59% respectively).Paracetamol was the drug most commonly used in overdose in both adults andchildren. In adults ethanol featured in 17% of cases. Ingestion of paraffin andrelated volatile hydrocarbons were the most important cause of acute poisoning inchildren. Acute poisoning admissions due to drugs of abuse, excluding ethanol,were minimal in both age groups (1%). Toxic exposures to non-drug chemicals inthe agricultural and industrial settings were low (3%). The number of exposures tobiological toxins was also minimal (2%). Summary of findings for Poison Centre inqueries (3744 consultations):In 1999 the Tygerberg Poison Information Centre received 3744 calls, of which2690 were related to acute human exposures to poisonous substances. Theremainder of the calls (1054) was either about drug therapy, or general non-patientrelated toxicological matters. There were more calls regarding poisoning in adults(61%) than in children (39%). Most of the paediatric poisonings were accidental(97%), whereas in adults 55% were deliberate and 45% accidental. Forty fourpercent of the children and 52% of adults were female. In children, inqueriesabout exposures to potentially harmful non-drug household chemical productscomprised 56% of poison calls, while drug overdose was 28% and exposures tobiological toxins 16%. In adults 44% of inqueries were with regard to householdproducts, 40% about drugs and 16% biological toxins.A comparison of Hospital admissions versus Poison Centre consultations:In order to make a valid comparison between Hospital admissions and PoisonCentre consultations, acute poisoning cases originating from the same area werecompared. Eight hundred and thirty four (90%) of patients admitted to TygerbergHospital and 592 (25%) of Poison Centre consultations originated from the sameregion, the Tygerberg catchment area. Several differences were noted whencomparing poisoning cases reported to the Poison Centre and Hospitaladmissions. Six hundred and eighty eight (83%) adults and 145 (17%) childrenwere admitted to Hospital in contrast to Poison Centre inqueries, where 322 (54%)were adults and 270 (46%) children. In adults, 99% of Hospital admissions versus59% of Poison Centre consultations were regarded as self-inflicted. Ninety three percent of adults admitted to Hospital were drug overdoses, whereas only 48% ofadult Poison Centre consultations involved ingestion of medicines. In adultoverdoses with paracetamol and other analgesics, tricyclic antidepressants,antiepileptics, theophylline and ethanol were significantly higher in Hospitaladmissions than in Poison Centre consultations. In contrast, exposures topesticides e.g. pyrethroids, misuse of recreational drugs e.g. cannabis andbiological toxin exposures e.g. spider bites, were significantly higher in PoisonCentre consultations than in Hospital admissions.In children, poisoning exposures to volatile hydrocarbons, especially paraffin, weresignificantly higher in Hospital admissions compared to Poison Centre enqueries.As is evident from the disparity in the results above, inqueries to the TygerbergPoison Information Centre cannot be regarded as a reflection of the true incidenceof acute poisonings in the community.Poison Information Centre statistics are distorted because of two factors:1. Under-reporting to the Poison Information Centre. Healthcare providersare familiar with how to manage drugs commonly used in overdose (e.g.paracetamol) and certain household non-drug chemicals (e.g. paraffin), andoften do not consult the Poison Centre for poison cases involving thesesubstances. The number of inqueries received by the Poison InformationCentre regarding these substances is, therefore, an under representation ofactual incidence. 2. Over-reporting to the Poison Information Centre. The Tygerberg PoisonInformation Centre is well known for its expertise in biological toxins (e.g.spider and snake bites, scorpion stings, plant and mushroom ingestions,and marine toxins). Therefore, the number of inqueries received by theCentre with regard to these exposures is far higher than actual incidence ofexposures.It is clear from this study that one cannot use data derived from a poison centrealone as an indicator of true incidence of poisoning in the community. A moreaccurate estimate of incidence of acute poisoning could be obtained by includingdata from hospital admissions, as well as those from primary health care facilities.Another prominent finding in this study was the high incidence of self-inflicted drugoverdose in adult females, with paracetamol being the drug of choice. Poisonprevention should therefore not be limited to children. Adult prevention programsneed urgent attention.

[发布机构] Stellenbosch University