Eillyne Seow

Forecasting daily attendances at an emergency department to aid resource planning

BackgroundAccurate forecasting of emergency department (ED) attendances can be a valuable tool for micro and macro level planning.MethodsData for analysis was the counts of daily patient attendances at the ED of an acute care regional general hospital from July 2005 to Mar 2008. Patients were stratified into three acuity categories; i.e. P1, P2 and P3, with P1 being the most acute and P3 being the least acute. The autoregressive integrated moving average (ARIMA) method was separately applied to each of the three acuity categories and total patient attendances. Independent variables included in the model were public holiday (yes or no), ambient air quality measured by pollution standard index (PSI), daily ambient average temperature and daily relative humidity. The seasonal components of weekly and yearly periodicities in the time series of daily attendances were also studied. Univariate analysis by t-tests and multivariate time series analysis were carried out in SPSS version 15.ResultsBy time series analyses, P1 attendances did not show any weekly or yearly periodicity and was only predicted by ambient air quality of PSI > 50. P2 and total attendances showed weekly periodicities, and were also significantly predicted by public holiday. P3 attendances were significantly correlated with day of the week, month of the year, public holiday, and ambient air quality of PSI > 50.After applying the developed models to validate the forecast, the MAPE of prediction by the models were 16.8%, 6.7%, 8.6% and 4.8% for P1, P2, P3 and total attendances, respectively. The models were able to account for most of the significant autocorrelations present in the data.ConclusionTime series analysis has been shown to provide a useful, readily available tool for predicting emergency department workload that can be used to plan staff roster and resource planning.

Case of carbon monoxide poisoning after smoking shisha

Carbon monoxide poisoning has been reported as a result of exposure to various sources of smoke, such as car exhaust fumes, home water heaters and tobacco smoke. We describe a case of symptomatic, moderately severe carbon monoxide (CO) poisoning in a young Mediterranean man after smoking a waterpipe, or shisha. This case highlights the importance of considering carbon monoxide exposure in patients presenting with non-specific neurological symptoms to the emergency department (ED).

Predicting Hospital Admissions at Emergency Department Triage Using Routine Administrative Data

OBJECTIVESnTo be able to predict, at the time of triage, whether a need for hospital admission exists for emergency department (ED) patients may constitute useful information that could contribute to systemwide hospital changes designed to improve ED throughput. The objective of this study was to develop and validate a predictive model to assess whether a patient is likely to require inpatient admission at the time of ED triage, using routine hospital administrative data.nnnMETHODSnData collected at the time of triage by nurses from patients who visited the ED in 2007 and 2008 were extracted from hospital administrative databases. Variables included were demographics (age, sex, and ethnic group), ED visit or hospital admission in the preceding 3 months, arrival mode, patient acuity category (PAC) of the ED visit, and coexisting chronic diseases (diabetes, hypertension, and dyslipidemia). Chi-square tests were used to study the association between the selected possible risk factors and the need for hospital admission. Logistic regression was applied to develop the prediction model. Data were split for derivation (60%) and validation (40%). Receiver operating characteristic curves and goodness-of-fit tests were applied to the validation data set to evaluate the model.nnnRESULTSnOf 317,581 ED patient visits, 30.2% resulted in immediate hospital admission. In the developed predictive model, age, PAC status, and arrival mode were most predictive of the need for immediate hospital inpatient admission. The c-statistic of the receiver operating characteristic (ROC) curve was 0.849 (95% confidence interval [CI] = 0.847 to 0.851). The goodness-of-fit test showed that the predicted patients admission risks fit the patients actual admission status well.nnnCONCLUSIONSnA model for predicting the risk of immediate hospital admission at triage for all-cause ED patients was developed and validated using routinely collected hospital data. Early prediction of the need for hospital admission at the time of triage may help identify patients deserving of early admission planning and resource allocation and thus potentially reduce ED overcrowding.

Geriatric assessment and intervention in an emergency department observation unit reduced re‐attendance and hospitalisation rates

Aim:u2002 To determine the efficacy of geriatric assessment and intervention in an emergency department observation unit (EDOU).

Exploring if day and time of admission is associated with average length of stay among inpatients from a tertiary hospital in Singapore: an analytic study based on routine admission data.

BackgroundIt has been postulated that patients admitted on weekends or after office hours may experience delays in clinical management and consequently have longer length of stay (LOS). We investigated if day and time of admission is associated with LOS in Tan Tock Seng Hospital (TTSH), a 1,400 bed acute care tertiary hospital serving the central and northern regions of Singapore.MethodsThis was a historical cohort study based on all admissions from TTSH from 1st September 2003 to 31st August 2004. Data was extracted from routinely available computerized hospital information systems for analysis by episode of care. LOS for each episode of care was log-transformed before analysis, and a multivariate linear regression model was used to study if sex, age group, type of admission, admission source, day of week admitted, admission on a public holiday or eve of public holiday, admission on a weekend and admission time were associated with an increased LOS.ResultsIn the multivariate analysis, sex, age group, type of admission, source of admission, admission on the eve of public holiday and weekends and time of day admitted were independently and significantly associated with LOS. Patients admitted on Friday, Saturday or Sunday stayed on average 0.3 days longer than those admitted on weekdays, after adjusting for potential confounders; those admitted on the eve of public holidays, and those admitted in the afternoons and after office hours also had a longer LOS (differences of 0.71, 1.14 and 0.65 days respectively).ConclusionCases admitted over a weekend, eve of holiday, in the afternoons, and after office hours, do have an increased LOS. Further research is needed to identify processes contributing to the above phenomenon.

The Ottawa Ankle Rules in Asia: validating a clinical decision rule for requesting X-rays in twisting ankle and foot injuries

This was a study to determine if the Ottawa Ankle Rules (OAR) for requesting x-ray studies in twisting ankle and foot injuries are applicable in our Asian population. Four hundred ninety-four consecutive eligible patients presenting to the emergency department with twisting injuries about the ankle were examined by emergency physicians for clinical criteria requiring ankle and foot x-ray studies according to the OAR. Four hundred eighty-eight of these patients underwent x-ray studies that were interpreted by a radiologist. The sensitivity and specificity of the OAR for predicting the presence of fracture were calculated to be 0.9 and 0.34, respectively. When the rules were modified to cast a wider screening net, sensitivity improved to 0.99. We conclude that the OAR are not applicable to our population because of inadequate sensitivity, but when modified become acceptable and can reduce the number of x-ray studies requested by 28%.

Predictors of frequent attenders of emergency department at an acute general hospital in Singapore

Objective To determine factors associated with frequent emergency department (ED) attendance at an acute general hospital in Singapore. Method Patients who attended the ED from 1 January to 31 December 2006 without prior attendance in the preceding 12u2005months (index attendance) were tracked for 12u2005months. Variables included in the analysis were age, gender, race, date and time of attendance, patient acuity category scale, mode of arrival, distance to ED and diagnosis based on ICD-9CM code. Frequent attenders were patients who attended the ED ≥5 times for any diagnosis within 12u2005months. Results A total of 82u2008172 patients in the study cohort accounted for a total of 117u2008868 visits within 12u2005months, of which 35u2008696 (30.3%) were repeat attendances. A total of 1595 patients (1.9%) were frequent attenders responsible for 8% of all repeat attendances. Stepwise logistic regression analysis found patients aged 75+u2005years, male, non-Chinese ethnic groups, Sunday and Monday, time of the attendance from 16:00 to midnight, distance to ED, chronic obstructive pulmonary disease, heart failure and acute respiratory infections to be significantly associated with frequent attendances. Conclusion With the ageing population and their complex healthcare needs, elderly patients with chronic medical conditions are expected to make up an increasing proportion of the workload of ED in the future. A systems approach and a disease and case management approach in collaboration with primary care providers are interventions recommended to stem this.

The pattern of ambulance arrivals in the emergency department of an acute care hospital in Singapore

Objectives—(1) To determine the pattern of ambulance arrivals in the emergency department (ED) and (2) to review resource allocation based on these data. Methods—All (13 697) ambulance arrivals in 1996 to the ED of Tan Tock Seng Hospital were studied and where relevant compared with the walk in and total arrivals of the same year. The following data were obtained from computer records: (a) patients demographic data; (b) number of ambulance arrivals by hour; (c) the classification of the ambulance arrivals by emergency or non-emergency, trauma or non-trauma; (d) cause of injury for trauma cases; (e) discharge status. Results—The ambulance arrivals in 1996 constituted 12.4% of the patient load for this department. There was no difference in modes of patient arrival to the ED by sex and ethnic group. However, there was significant evidence to show that more patients age > 60 came by ambulance than those age < 12 (p << 0.01). Some 98.5% of the ambulance arrivals were emergencies; 40.7% of the ambulance arrivals were attributable to trauma versus 27.3% of the walk in arrivals. The majority of the trauma cases brought in by ambulance were because of road traffic accidents (15.3%) or home accidents (7.4%). The peak in ambulance arrivals was between 2100–2300 hours compared with 1000–1200 for the walk in arrivals. More than half of the ambulance arrivals were admitted. Conclusion—In planning resource allocation and in the development of contingency plans, the resource use of ambulance patients and the pattern of their arrivals should be taken into account.

Resuscitation for patients with out-of-hospital cardiac arrest: Singapore.

AIMnTo evaluate characteristics and outcome of out-of-hospital cardiac arrest (OHCA) patients presenting to the Emergency Department (ED), and to examine factors that could be used to determine to prolong or abort resuscitation for these patients.nnnMETHODnAll OHCA patients presenting to the ED were studied over a three-month period from November 2001 through January 2002. Patient with traumatic cardiac arrest were excluded. Data were collected from the ambulance case records, ED resuscitation charts, and the ED Very High Frequency (VHF) radio case-log sheet. Information collected included the patients demographic characteristics, timings (time from call to ambulance arrival on scene, time from arrival at scene to departure from scene, time from scene to arrival in the ED) recorded in the pre-hospital setting, the outcome of the resuscitation, and the final outcome for patients who survived ED resuscitation.nnnRESULTSnNinety-three non-traumatic patients with an OHCA were studied during the three-month period. Of the 93 patients, 15 (16.1%) survived ED resuscitation, and one survived to hospital discharge. There were no statistically significant differences for age, race, or gender with regards to the outcome of the resuscitation. The initial cardiac rhythms were asystole (65), pulseless electrical activity (21), and ventricular fibrillation (7). Fourteen (15%) received bystander cardiopulmonary resuscitation (CPR). All seven patients with return of spontaneous circulation (ROSC) on arrival in the ED survived ED resuscitation. The ambulance took an average of 11.80 +/- 3.36 minutes for the survivors and 11.8 +/- 4.22 minutes for the non-survivors from the time of call to get to these patients. The average of the scene times was 12.5 +/- 4.61 minutes for the survivors and 12.0 +/- 4.02 minutes for the non-survivors. Transport time from the scene to the ED took an average of 39.1 +/- 8.32 minutes for the survivors and 37.2 +/- 9.00 minutes for the non-survivors.nnnCONCLUSIONnThe survival rate for patients with OHCA after ED resuscitation is similar to the results from other studies. There is a need to increase the awareness and delivery of basic life support by public education. Automatic External Defibrillators (AED) should be available widely to ensure that the chance of early defibrillation is increased. Prolonged resuscitation efforts appear to be futile for OHCA patients if the time from cardiac arrest until arrival in the ED is > or = 30 minutes coupled with no ROSC, and if continuous asystole has been documented for > 10 minutes.

Review of studies and guidelines on fasting and procedural sedation at the emergency department.

AIMnProcedural sedation and analgesia allows urgent procedures to be performed safely by preserving patients airway reflexes. Fasting, which is required before deeper levels of sedation, and where the airway reflexes are not preserved, is difficult to impose in emergencies. This paper aims to synthesise evidence on the need for pre-procedure fasting to minimise aspiration among adults undergoing procedural sedation and analgesia for emergency procedures.nnnMETHODSnOverviews, guidelines with graded recommendations and primary studies on aspiration and pre-procedure fasting in procedural sedation and analgesia were retrieved from Medline, Cochrane, and Center for Reviews and Dissemination Databases. Terms searched were procedural sedation, fasting, emergency and sedation.nnnRESULTSnOne primary study and one guideline were included. The American College of Emergency Physicians Clinical Policies Subcommittee on Procedural Sedation and Analgesia issued a recommendation based on preliminary, inconclusive or conflicting evidence, or on panel consensus. The recommendation states: recent food intake is not a contraindication for administering procedural sedation and analgesia.... The primary study conducted by Bell in an emergency department in Australia compared patients who last ate or drank more than 6 and 2 h from induction, respectively, with those who last ate or drank within 6 and 2 h. There were no cases of aspiration in both groups. Out of 118 patients who fasted, 1 (0.8%) vomited, as did one of 282 patients (0.4%) who did not fast.nnnCONCLUSIONSnAspiration risk is expected to be lower in procedural sedation and analgesia than in general anaesthesia. Current guidelines rely on expert consensus due to the lack of primary studies. Contextualisation of existing guidelines are quick and efficient strategies for developing locally relevant tools.