Hot Water Immersion Therapy with a Thermal Isolator in Patient with Marine Envenomation

Objective

Hot water immersion (HWI) has been proven to be effective for the treatment of pain due to marine envenomation. Our preliminary study by simply measuring the temperature change over time on the hot water in our conventional metal tray method revealed a too rapid fall in water temperature that happened in minutes. The aim of this study was to review the current practice of HWI for patients with marine envenomation in the emergency departments in Hong Kong, and to look for the optimal equipment in performing HWI.

Method

We first conducted a phone survey to 16 registered nurses or nursing officers from 16 emergency departments of public hospitals in Hong Kong for the current practice of hot water immersion. The second part of our study was an in-vitro experiment done in observation room that a healthy subject immersed a hand into the water bath in metallic tray, sharp box and thermal isolator with and without covering of aluminum foil or plastic foil. The temperature change of the water bath in these containers was serially monitored.

Results

In our phone survey, 14 respondents used plastic tray or sharp box for hot water immersion. Nine of them claimed that they commonly encountered inadequate wound pain relief and early cooling of the hot water bath. The experiment showed that the water temperature dropped out of optimal range for 5 minutes and 15 minutes in metallic tray and sharp box respectively. The thermal isolator kept the optimal temperature throughout 30 minutes of the study time.

Conclusion

Our purposed thermal isolator is a safe, practical and effective device for HWI therapy.

Timolol Eye Drops Induced Bradycardia

We report a 25-year-old man with bradycardia after administration of ophthalmic timolol. The patient was asymptomatic, and his bradycardia resolved after stopping the eye drop. He was discharged after a four-hour observation. This case demonstrated that topical timolol eye drop may cause systemic adverse reaction. The use of timolol and its possible side-effects are discussed.

Hong Kong Poison Information Centre: Annual Report 2011

Objective

To report and analyse the poisoning data of Hong Kong Poison Information Centre (HKPIC) in 2011.

Methods

In 2011, all poisoning cases received by HKPIC were retrieved from its database: Poison Information and Clinical Management System (PICMS) for analysis.

Results

A total of 4,331 poisoned cases were analysed. There were 1,915 male patients (44.2%), 2,411 female patients (55.7%) and 5 patients with sex unknown. More than two-third (68%) of them were between 20 and 59 years old. Common causes of exposure were suspected self-harm/suicidal attempt, unintentional exposure and abusive use. Paracetamol, benzodiazepine, household product, zopiclone, and Chinese herbal medicine were the top five commonest poisons encountered. Majority of the patients were managed supportively, with 12.1% and 8.5% treated by decontamination and antidotes respectively. Most cases had uneventful recovery; 1.0% of the poison exposure resulted in death and 4.8% of the exposure had major outcomes.

Conclusions

This 6th annual report provided updated epidemiological information on poisoning pattern in Hong Kong and emphasized some changes in comparing with our previous reports.

Two Cases of Anticholinergic Poisoning from Transdermal Scopolamine Patch

Scopolamine transdermal patch is a form of anticholinergic drug used to prevent motion sickness. We reported two cases of anticholinergic poisoning resulting from scopolamine transdermal patch. The first case experienced local toxicity and presented with right eye mydriasis for five days. The second case developed systemic anticholinergic toxidrome contributed by the scopolamine patch and presented with acute confusion. She was treated successfully by physostigmine, an anticholinergic antidote. The recommendation on physostigmine use was also discussed. We hope that these two case reports will raise the clinician awareness of the potential side effect of this kind of product.

Hong Kong Poison Information Centre: Annual Report 2006

Objective

To report the poisoning data of Hong Kong Poison Information Centre (HKPIC) in 2006.

Methods

From 1st January 2006 to 31st December 2006, all poisoning cases received by HKPIC were retrieved from its database (DATOX) for analysis.

Results

A total of 2555 poisoned cases were analysed. There were 1051 male and 1466 female patients and nearly 60% of the cases were between 20 and 49 years old. Common causes of exposure were suicidal attempts and accidents. Paracetamol, sedative-hypnotic and household products were common sources of poison exposure. The majority of the patients were managed conservatively, with 18.8% and 10.5% treated by decontamination and antidotes respectively. Most cases had uneventful recovery; less than 1% of the poison exposure resulted in death and about 5% of the exposure had major outcomes. Nearly half of the cases were managed in the accident & emergency department without hospitalisation.

Conclusions

This annual report provides updated epidemiological information on poisoning in Hong Kong. Subsequent annual reports would provide important information on the trend of poisoning pattern and may guide further strategies in poison control and prevention in Hong Kong.

Hong Kong Poison Information Centre: Annual Report 2012

Objective

To report and analyze the poisoning data of Hong Kong Poison Information Centre (HKPIC) in 2012.

Methods

In 2012, all poisoning cases received by HKPIC were retrieved from its database: Poison Information and Clinical Management System (PICMS) for analysis.

Results

A total of 4,814 poisoned cases were analyzed. There were 1,771 male patients (42.3%), 2,399 female patients (57.3%) and 14 sex unspecified patients (0.3%). Middle aged group (30-39 years) contributed about one-fifth (20.1%) of the poisoning cases while more than two-third (67.7%) of them were between 20 and 59 years old. Common causes for poisoning were suspected self-harm/suicidal attempt (45%), abusive substances use (13.9%) and unintentional exposure (13.0%). Five commonest types of poison exposed were paracetamol, benzodiazepine, zopiclone, bites and envenomation and household products. Majority of the patients were managed with supportive measures, and 15.7% and 11.9% of them were treated by decontamination and antidotes respectively. Most cases had uneventful recovery; 0.6% of the poison exposure resulted in death and 4.7% of the exposure had major outcomes.

Conclusions

This seventh annual report provides updated epidemiological information on poisoning pattern in Hong Kong and highlights important changes in comparing with our previous reports. (Hong Kong j.emerg.med. 2013;20:371-381)

A Retrospective Survey on the Clinical Presentation of Ketamine Abusers in a Hong Kong Emergency Department

Objective

Ketamine is one of the commonest abusing agents in Hong Kong. Our study aims to identify their clinical pattern of presentations to emergency departments.

Method

This is a retrospective survey study. The studied group was ketamine abusers being referred to us from a source out of emergency department (ED). Control group was randomly selected from patients attending our ED. The electronic records of the ketamine abusers and the controls in the past 3 years (1st April 2004-31st March 2007) were reviewed and analysed.

Result

Total 91 subjects (48 in ketamine group, 43 in control group) were included. The mean age of ketamine abusers and control group are 21 and 22.2 year-old respectively. Most of them (97.9%) did not declare their background of ketamine abuse. The mean 3-year attendance rate for the ketamine group was 2.38 and for control group was 0.91, with a difference of 1.47 (95% CI 0.54-2.41, p=0.003). Most of their illnesses were diagnosed as epigastric pain (25%), followed by upper respiratory tract infection (18.8%), head injury (10.4%) and urinary tract infection (10.4%). Significantly higher number of ketamine abusers presented with epigastric pain compared with control group (odds ratio 143, p<0.001).

Conclusion

Most teenage ketamine abusers do not declare their background of drug abuse when they present to emergency departments. They tend to have a higher frequency of attendances. Most of their presenting problems are related to gastrointestinal system.

Hong Kong Poison Information Centre: Annual report 2016

Objective:

To report and analyse the poisoning data of Hong Kong Poison Information Centre in 2016.

Methods:

In 2016, all poisoning cases received by Hong Kong Poison Information Centre were retrieved from its database (Poison Information and Clinical Management System) for analysis.

Results:

A total of 4096 poisoned cases were analysed. There were 1871 male patients (45.7%), 2203 female patients (53.8%) and 22 sex unspecified patients (0.5%). The majority of the cases (63.1%) were between 20 and 59 years old. Common causes for poisoning were suspected self-harm/suicidal attempt (36.3%), unintentional exposure (18.4%) and abusive use (13.1%). Excluding the common co-ingestant ethanol, the five commonest types of poisons were benzodiazepines, paracetamol, household products, zopiclone and Chinese herbal medicine. Most patients were managed with supportive measures, while 14.3% and 12.9% of them were treated by decontamination and antidotes, respectively. Majority of the cases had uneventful recovery; 1% resulted in death and 3.9% had major outcomes. Six interesting cases and three poisoning outbreaks were discussed.

Conclusion:

This 11th annual report provided the updated epidemiological information on poisoning pattern in Hong Kong and highlighted important changes in comparing with our previous reports.

Safety profile of snake antivenom (use) in Hong Kong - a review of 191 cases from 2008 to 2015

INTRODUCTION

The mainstay of treatment for significant envenoming from snakebites is antivenom. However, there is insufficient data regarding the safety of antivenom used in Hong Kong. We describe the incidence of hypersensitivity reactions from antivenom use and review the frequency and reasons for intensive care unit (ICU) admission.

METHODS

The Hong Kong Poisons Information Centre database was reviewed. All patients given snake antivenom between 2008 and 2015 were included. Patient demographics, species of snake involved, details of antivenom used, treatment location, use of pre-treatment, reasons for ICU admission (where applicable) and details of early and late antivenom reactions were extracted.

RESULTS

There were 191 patients who received snake antivenom. Most (93%) were treated with either the green pit viper antivenom from Thailand or the Agkistrodon halys antivenom from China. The incidences of early hypersensitivity reactions to green pit viper antivenom and Agkistrodon Halys antivenom were 4.7% and 1.4%, respectively. Most patients (69%) were managed in the ED observation ward or general ward. There were 59 patients managed in ICU, most (90%) of whom were admitted for close monitoring during antivenom administration. There were no cases of significant morbidity from antivenom administration. Eight patients (5.6%) had features suggestive of mild serum sickness.

CONCLUSIONS

The incidence of immediate hypersensitivity reaction to antivenom commonly used in Hong Kong is low. Majority of patients were managed safely in the emergency department observation ward or general ward. Serum sickness appears to be uncommon and possible cases presented with mild features.

Two cases of valproic acid poisoning treated with l-carnitine

Two cases of acute valproic acid poisoning with central nervous system depression and raised ammonia level without hepatotoxicity were reported. They were treated successfully with the use of the antidotes: l-carnitine and other supportive measures. Clinical manifestation and progress was described, and discussion is focused on the use of l-carnitine in valproic acid–induced hyperammonemia, from its mechanism to the clinical experiences in the literature. Based on the favorable response of our two cases and the literature review, we recommend the administration of intravenous l-carnitine in patients of valproic acid overdose with hyperammonemia or valproic acid–induced hyperammonemic encephalopathy and hepatotoxicity at a dose of 50 mg/kg every 8 h for the first initial 24 h with further individual assessment.

Mushroom poisoning in Hong Kong: a ten-year review

INTRODUCTION

Mushroom poisoning is a cause of major mortality and morbidity all over the world. Although Hong Kong people consume a lot of mushrooms, there are only a few clinical studies and reviews of local mushroom poisoning. This study aimed to review the clinical characteristics, source, and outcome of mushroom poisoning incidences in Hong Kong.

METHODS

This descriptive case series review was conducted by the Hong Kong Poison Information Centre and involved all cases of mushroom poisoning reported to the Centre from 1 July 2005 to 30 June 2015.

RESULTS

Overall, 67 cases of mushroom poisoning were reported. Of these, 60 (90%) cases presented with gastrointestinal symptoms of vomiting, diarrhoea, and abdominal pain. Gastrointestinal symptoms were early onset (<6 hours post-ingestion) and not severe in 53 patients and all recovered after symptomatic treatment and a short duration of hospital care. Gastrointestinal symptoms, however, were of late onset (≥6 hours post-ingestion) in seven patients; these were life-threatening cases of amatoxin poisoning. In all cases, the poisonous mushroom had been picked from the wild. Three cases were imported from other countries, and four collected and consumed the amatoxin-containing mushrooms in Hong Kong. Of the seven cases of amatoxin poisoning, six were critically ill, of whom one died and two required liver transplantation. There was one confirmed case of hallucinogenic mushroom poisoning caused by Tylopilus nigerrimus after consumption of a commercial mushroom product. A number of poisoning incidences involved the consumption of wild-harvested dried porcini purchased in the market.

CONCLUSION

Most cases of mushroom poisoning in Hong Kong presented with gastrointestinal symptoms and followed a benign course. Life-threatening cases of amatoxin poisoning are occasionally seen. Doctors should consider this diagnosis in patients who present with gastrointestinal symptoms that begin 6 hours or more after mushroom consumption.

Paracetamol overdose in Hong Kong: is the 150-treatment line good enough to cover patients with paracetamol-induced liver injury?

OBJECTIVES

To evaluate the failure rate of the 150-treatment line for paracetamol overdose in Hong Kong, and the impact if the treatment threshold was lowered.

SETTING

Public hospitals, Hong Kong.

PATIENTS

All patients with acute paracetamol overdose reported to the Hong Kong Poison Information Centre from 1 January 2011 to 31 December 2013 were studied and analysed for the timed serum paracetamol concentration and their relationship to different treatment lines. Presence of significant liver injury following paracetamol overdose was documented. The potential financial burden of different treatment lines implemented locally was estimated.

RESULTS

Of 893 patients, 187 (20.9%) had serum paracetamol concentration above the 150-treatment line, 112 (12.5%) had serum paracetamol concentration between the 100- and 150-treatment lines, and 594 (66.5%) had serum paracetamol level below the 100-treatment line. Of the 25 (2.8%) patients who developed significant liver injury, two were between the 100- and 150-treatment lines, and the other two were below the 100-treatment line. The failure rate of the 150-treatment line was 0.45%. Lowering the treatment threshold to the 100-treatment line might lower the failure rate of the treatment nomogram to 0.22% but approximately 37 more patients per year would need to be treated. It would incur an additional annual cost of HK$189 131 (US$24 248), and an additional 1.83 anaphylactoid reactions per year. The number needed-to-treat to potentially reduce one significant liver injury is 112.

CONCLUSIONS

Lowering the treatment threshold of paracetamol overdose may reduce the treatment-line failure rate. Nonetheless such a decision must be balanced against the excess in treatment complications and health care resources.

Surveillance of emerging drugs of abuse in Hong Kong: validation of an analytical tool

OBJECTIVE

To validate a locally developed chromatography-based method to monitor emerging drugs of abuse whilst performing regular drug testing in abusers.

DESIGN

Cross-sectional study.

SETTING

Eleven regional hospitals, seven social service units, and a tertiary level clinical toxicology laboratory in Hong Kong.

PARTICIPANTS

A total of 972 drug abusers and high-risk individuals were recruited from acute, rehabilitation, and high-risk settings between 1 November 2011 and 31 July 2013. A subset of the participants was of South Asian ethnicity. In total, 2000 urine or hair specimens were collected.

MAIN OUTCOME MEASURES

Proof of concept that surveillance of emerging drugs of abuse can be performed whilst conducting routine drug of abuse testing in patients.

RESULTS

The method was successfully applied to 2000 samples with three emerging drugs of abuse detected in five samples: PMMA (paramethoxymethamphetamine), TFMPP [1-(3-trifluoromethylphenyl)piperazine], and methcathinone. The method also detected conventional drugs of abuse, with codeine, methadone, heroin, methamphetamine, and ketamine being the most frequently detected drugs. Other findings included the observation that South Asians had significantly higher rates of using opiates such as heroin, methadone, and codeine; and that ketamine and cocaine had significantly higher detection rates in acute subjects compared with the rehabilitation population.

CONCLUSIONS

This locally developed analytical method is a valid tool for simultaneous surveillance of emerging drugs of abuse and routine drug monitoring of patients at minimal additional cost and effort. Continued, proactive surveillance and early identification of emerging drugs will facilitate prompt clinical, social, and legislative management.

Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong

OBJECTIVE

To study the epidemiology, causes, and clinical course of Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong.

DESIGN

Case series.

SETTING

Hong Kong.

PATIENTS

All case histories of Chinese herbal medicine-induced anticholinergic poisoning (with laboratory confirmation) recorded by the Hong Kong Poison Information Centre over a 93-month period were accessed for analysis.

RESULTS

During the relevant period, 22 clusters of Chinese herbal medicine-induced anticholinergic poisoning involving 32 patients were retrieved. The commonest clinical features were mydriasis (n=32, 100%) and confusion (n=24, 75%). No gastro-intestinal decontamination was performed. None of these patients underwent intubation, defibrillation, cardioversion, pacing, fluid resuscitation, inotropic support or dialysis. Of the 32 patients, 17 (53%) were treated with physostigmine because of confusion, three of whom had previously received intravenous benzodiazepines. No patient could be effectively treated with benzodiazepines alone. There was no mortality, and all the patients were discharged within 3 days. None of them re-attended the emergency department within 1 week of discharge. The commonest cause was the substitution of flos campsis (Campsis grandiflora) by the flower of the Datura species (7 clusters [32%] in 10 patients).

CONCLUSION

Mydriasis and confusion were the commonest clinical features of Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong. Physostigmine was frequently used in the treatment; benzodiazepines appeared ineffective. The commonest cause was the substitution of flos campsis (Campsis grandiflora) by the flower of the Datura species.

Aconite poisoning over 5 years: a case series in Hong Kong and lessons towards herbal safety

BACKGROUND

Aconite poisoning is a severe, life-threatening poisoning related to the use of traditional Chinese medicine (TCM). Despite current legislation, repeated poisoning cases are steadily encountered.

OBJECTIVE

The aim of the study was to summarize the clinical features and to elucidate the causative and contributory factors leading to aconite poisoning.

METHODS

This study was conducted within the Hospital Authority Toxicology Reference Laboratory, which is the sole tertiary referral clinical toxicology laboratory in Hong Kong. This retrospective study reviewed all confirmed aconite poisoning cases handled by a clinical toxicology laboratory between April 2004 and July 2009. The diagnosis in all cases was confirmed biochemically by detecting aconitum alkaloids in urine specimens. Additionally, herbal specimens were morphologically identified and herbal formulae were studied and transcribed. The cause of poisoning for each case was determined whenever possible.

RESULTS

Fifty-two cases were examined in this aconite poisoning case series. Neurological, cardiovascular and gastrointestinal toxicities were encountered in 49 (94.2%), 46 (88.5%) and 31 (59.6%) patients, respectively. The poisoning was severe in 6 (11.5%) patients, moderate in 17 (32.7%) patients and mild in 29 (55.8%) patients. Amongst 44 patients (84.6%) in whom the underlying reasons of poisoning could be determined, four major causes were found. These included overdose - prescription of a higher than recommended dosage of aconite herbs in 17 (32.7%) cases; 'hidden' poisoning (the aconite herb was not prescribed but dispensed inadvertently) in 17 (32.7%) cases; usage of inadequately processed herbs in 7 (13.5%) cases; and dispensary error in 2 (3.9%) cases. No case fatality was recorded.

CONCLUSION

In the majority of cases in this series, the causes of poisoning can be traced to poor-quality herbs, poor quality of prescription practice, or dispensary errors. The quality issues of TCM practice should be critically addressed to minimize this poisoning threat.

Accuracy of clinical diagnosis versus the World Health Organization case definition in the Amoy Garden SARS cohort

OBJECTIVES

To compare the diagnostic accuracy of emergency department (ED) physicians with the World Health Organization (WHO) case definition in a large community-based SARS (severe acute respiratory syndrome) cohort.

METHODS

This was a cohort study of all patients from Hong Kong's Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical findings and WHO case definition criteria were recorded, along with ED diagnoses. Final diagnoses were established independently based on relevant diagnostic tests performed after the ED visit. Emergency physician diagnostic accuracy was compared with that of the WHO SARS case definition. Sensitivity, specificity, predictive values and likelihood ratios were calculated using standard formulae.

RESULTS

During the study period, 818 patients presented with SARS-like symptoms, including 205 confirmed SARS, 35 undetermined SARS and 578 non-SARS. Sensitivity, specificity and accuracy were 91%, 96% and 94% for ED clinical diagnosis, versus 42%, 86% and 75% for the WHO case definition. Positive likelihood ratios (LR+) were 21.1 for physician judgement and 3.1 for the WHO criteria. Negative likelihood ratios (LR-) were 0.10 for physician judgement and 0.67 for the WHO criteria, indicating that clinician judgement was a much more powerful predictor than the WHO criteria.

CONCLUSIONS

Physician clinical judgement was more accurate than the WHO case definition. Reliance on the WHO case definition as a SARS screening tool may lead to an unacceptable rate of misdiagnosis. The SARS case definition must be revised if it is to be used as a screening tool in emergency departments and primary care settings.

Dettol poisoning and the need for airway intervention

OBJECTIVES. To (1) characterise the clinical features of Dettol poisoning on a territory-wide basis, (2) assess the need for airway intervention after such poisoning and its time frame after ingestion, and (3) identify predictors for such an intervention. DESIGN. Case series. SETTING. Sixteen accident and emergency departments in Hong Kong. PATIENTS. Patients with Dettol ingestion who presented within 48 hours of ingestion from July 2005 to June 2009, derived from the database of the Hong Kong Poison Information Centre. RESULTS. In all, 213 patient records were identified, of which 36 were excluded based on pre-defined criteria and 177 were analysed. Among the latter, the median age was 32 (range, 2-95) years and the male-to-female ratio was 1:2.7 (48:129). Intentional ingestion constituted the majority (95%) of cases. The most common symptoms were related to the local irritative/corrosive effects on the aero-digestive tract, such as gastro-intestinal upset and localised throat pain. Airway intervention was required in 14 (8%) patients. All interventions were performed within 12 hours of Dettol ingestion and three cases involved re-intubation after extubation. Univariate analysis showed that a Glasgow Coma Scale score of <8, older age, a larger amount ingested, lip swelling, lung crackles, and wheezing were all associated with airway intervention. In the multivariate analysis using forward stepwise logistic regression, only coma (Glasgow Coma Scale score of <8) remained statistically significant. CONCLUSIONS. Delayed airway obstruction (>12 hours after Dettol ingestion) is unlikely. For those who are intubated, careful assessment of airway adequacy before extubation is strongly recommended to avoid extubation failure and subsequent re-intubation. Patients in coma (Glasgow Coma Scale score of <8) should prompt airway intervention.

Green pit viper antivenom from Thailand and Agkistrodon halys antivenom from China compared in treating Cryptelytrops albolabris envenomation of mice

OBJECTIVE

To compare the relative efficacy of the green pit viper antivenom from Thailand and Agkistrodon halys antivenom from China. DESIGN. In-vivo experimental study.

SETTING

A wildlife conservation organisation, a university, a poison information centre, and a regional hospital in Hong Kong.

MAIN OUTCOME MEASURES

Pre- and post-antivenom lethal dose 50 (LD50) of the Cryptelytrops albolabris venom, median effective dose (ED50) of green pit viper antivenom and Agkistrodon halys antivenom against a lethal dose of the venom. SUBJECTS. Adult mice.

RESULTS

The intraperitoneal LD50 of the venom from locally caught Cryptelytrops albolabris was 0.14 microL. After post-exposure treatment with 10 microL of antivenom, it was elevated to 0.36 microL and 0.52 microL by the green pit viper antivenom and the Agkistrodon halys antivenom, respectively. The ED50 was 32.02 microL for green pit viper antivenom and 6.98 microL for Agkistrodon halys antivenom. Both green pit viper antivenom and Agkistrodon halys antivenom ameliorated the lethality of Cryptelytrops albolabris venom in mice.

CONCLUSION

The overall superior neutralisation capacity of Agkistrodon halys antivenom over green pit viper antivenom may be related to the geographic proximity of the venoms used for antivenom preparation. The results point towards the need for further comparison of the two antivenoms on protein or immunoglobulin weight basis, and with respect to non-lethal clinically significant toxicities.

Prediction of prognosis in acute paraquat poisoning using severity scoring system in emergency department

OBJECTIVE

The aim of this study was to validate and compare the performance of serum paraquat level, severity index of paraquat poisoning (SIPP), Acute Physiology And Chronic Health Evaluation II (APACHE II), modified Simplified Acute Physiology Score II (MSAPS II), and modified Expanded Simplified Acute Physiology Score II (MSAPS IIe) calculated immediately after arrival on emergency department (ED) for assessing the mortality of acute paraquat poisoning.

METHODS

A retrospective study design was employed with the main outcome measure being mortality from year 2001 to 2010. MSAPS II and MSAPS IIe were employed in that assessment of the 24-hour urine output were not included. The performance of APACHE II, MSAPS II, MSAPS IIe, serum paraquat level and SIPP for prediction of mortality in acute paraquat poisoning were compared.

RESULTS

A total of 102 patients were enrolled in the study. The area under the ROC curve for APACHE II (0.800) was statistically lower than those for MSAPS II, MSAPS IIe, SIPP and serum paraquat (0.879, 0.893, 0.924,and 0.951, respectively). The Hosmer-Lemeshow goodness-of-fit test C statistic revealed that APACHE II, MSAPS II, MSAPS IIe and serum paraquat level showed good calibrations (chi-square 8.477 and p = 0.388, chi-square 4.614 and p = 0.798, chi-squared 5.301 and p = 0.725, chi-squared 1.009 and p = 0.985 respectively), but poor calibration for SIPP (chi-square 21.293 and p = 0.006).

CONCLUSION

Serum paraquat level is still the most reliable prognosis factor in acute paraquat poisoning. But MSAPS II or MSAPS IIe calculated immediately after arrival on ED may be helpful to predict mortality in acute paraquat poisoning especially when hospital has no facility to measure serum paraquat level.

Causality assessment of herb-induced liver injury using multidisciplinary approach and Roussel Uclaf Causality Assessment Method (RUCAM)

OBJECTIVE

To evaluate an algorithmic approach involving a multidisciplinary team for causality assessment of suspected herb-induced liver injury (HILI) cases and to compare the causality score using this multidisciplinary approach and Roussel Uclaf Causality Assessment Method (RUCAM).

METHODS

A team consisting of hepatologist, clinical toxicologist, analytical toxicologist, and Chinese medicine (CM) pharmacist was formed to do causality assessment based on a protocol for suspected HILI cases. The likelihood of the diagnosis of individual case was first assessed systematically by a hepatologist and clinical toxicologist independently after collecting information about four aspects: (1) clinical course, (2) exclusion of alternative causes, (3) quality of the prescription and herbal product by examining the CM prescriptions and analysis of biological and herb samples, (4) scientific support on comprehensive literature review on English and Chinese medical database, and subsequently concluded in a consensus meeting held by the multidisciplinary team. The final causality score of each patient was compared with the likelihood of causality as assessed by RUCAM.

RESULTS

Between 2005 and 2007, 48 consecutive patients with suspected HILI were enrolled and 21 patients were excluded due to the establishment of an alternative cause of liver impairment or the lack of any information on the herbs taken. Twenty-seven patients were recruited, among them 15 consumed Chinese herbal medicines, 10 used proprietary Chinese medicinal products, and 2 used both. The concordance between the causality assessment of the hepatologist and clinical toxicologist was moderate (weighted κ = 0.48, 95%CI 0.30-0.66). The causality assessment process concluded that the likelihood of HILI was "highly probable" in 5 cases and "probable" in 12, whereas there were 5 "highly probable" and 16 "probable" cases as assessed by RUCAM. The causality assessment by the multidisciplinary approach and RUCAM also showed moderate agreement (weighted κ= 0.51, 95%CI 0.22-0.81).

CONCLUSION

A multidisciplinary approach using defined algorithms is a scientific approach in causality assessment for HILI. Further study is needed to assess its accuracy and applicability.

Early clinical predictors of severe acute respiratory syndrome in the emergency department

OBJECTIVES

To assess the association of diagnostic predictors available in the emergency department (ED) with the outcome diagnosis of severe acute respiratory syndrome (SARS).

METHODS

This retrospective cohort study describes all patients from the Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical and diagnostic predictors were recorded, along with ED diagnoses. Final diagnoses were established independently based on diagnostic tests performed after the ED visit. Associations of key predictors with the final diagnosis of SARS were described.

RESULTS

Of 821 patients, 205 had confirmed SARS, 35 undetermined SARS and 581 non-SARS. Multivariable logistic regression showed that the strongest predictors of SARS were abnormal chest x-ray (odds ratio [OR] = 17.4), subjective fever (OR = 9.7), temperature degrees >38 degrees C (OR = 6.4), myalgias (OR = 5.5), chills and rigors (OR = 4.0) and contact exposure (OR = 2.6). In a subset of 176 patients who had a complete blood cell count performed, the strongest predictors were temperature >or=38 degrees C (OR = 15.5), lymphocyte count <1000 (OR = 9.3) and abnormal chest x-ray (OR = 5.7). Diarrhea was a powerful negative predictor (OR = 0.03) of SARS.

CONCLUSIONS

Two components of the World Health Organization case definition - fever and contact exposure - are helpful for ED decision-making, but respiratory symptoms do not discriminate well between SARS and non-SARS. Emergency physicians should consider the presence of diarrhea, chest x-ray findings, the absolute lymphocyte count and the platelet count as significant modifiers of disease likelihood. Prospective validation of these findings in other clinical settings is desirable.

Emergency department presentation of ketamine abusers in Hong Kong: a review of 233 cases

OBJECTIVES

To study the acute clinical presentations of ketamine abusers in Hong Kong.

DESIGN

Retrospective chart review.

SETTING

Fifteen accident and emergency departments in Hong Kong.

PATIENTS

Consultations associated with recent ketamine use either confirmed by history or urine test were searched for from the database of the Hospital Authority Hong Kong Poison Information Centre from 1 July 2005 to 30 June 2008. Their medical records and investigation results were analysed.

RESULTS

A total of 233 records of ketamine use were included for review. Patient ages ranged from 13 to 60, with a median of 22 years, and the male-to-female ratio being 2.1:1. The most common symptoms of ketamine misuse were impaired consciousness (45%), abdominal pain (21%), lower urinary tract symptoms (12%), and dizziness (12%). The most common abnormal physical findings were high blood pressure (40%), followed by tachycardia (39%), abdominal tenderness (18%), and white powder in the nostrils (17%).

CONCLUSION

Most ketamine abusers presented acutely with transient central nervous system depression, abdominal pain, or lower urinary tract symptoms. Clinicians should be alert to the typical age-group, signs and symptoms of such abusers presenting in an acute medical setting.