Nature and extent of selection bias resulting from convenience sampling in the emergency department.

BACKGROUND: To compare the clinical and demographic variables of patients who present to the ED at different times of the day in order to determine the nature and extent of potential selection bias inherent in convenience sampling METHODS: We undertook a retrospective, observational study of data routinely collected in five EDs in 2019. Adult patients (aged ≥18 years) who presented with abdominal or chest pain, headache or dyspnoea were enrolled. For each patient group, the discharge diagnoses (primary outcome) of patients who presented during the day (08:00-15:59), evening (16:00-23:59), and night (00:00-07:59) were compared. Demographics, triage category and pain score, and initial vital signs were also compared. RESULTS: 2500 patients were enrolled in each of the four patient groups. For patients with abdominal pain, the diagnoses differed significantly across the time periods (p<0.001) with greater proportions of unspecified/unknown cause diagnoses in the evening (47.4%) compared with the morning (41.7%). For patients with chest pain, heart rate differed (p<0.001) with a mean rate higher in the evening (80 beats/minute) than at night (76). For patients with headache, mean patient age differed (p=0.004) with a greater age in the daytime (46 years) than the evening (41). For patients with dyspnoea, discharge diagnoses differed (p<0.001). Asthma diagnoses were more common at night (12.6%) than during the daytime (7.5%). For patients with dyspnoea, there were also differences in gender distribution (p=0.003), age (p<0.001) and respiratory rates (p=0.003) across the time periods. For each patient group, the departure status differed across the time periods (p<0.001). CONCLUSION: Patients with abdominal or chest pain, headache or dyspnoea differ in a range of clinical and demographic variables depending upon their time of presentation. These differences may potentially introduce selection bias impacting upon the internal validity of a study if convenience sampling of patients is undertaken.

Risk events during intrahospital transport of patients from the emergency department: a prospective observational study.

BACKGROUND: We aimed to determine the incidence, nature of and predisposing factors for risk events (REs) that occur during the intrahospital transport of patients from the ED. METHODS: We undertook a prospective, observational study of intrahospital patient transports from a single ED between 30 January and 20 March 2020. An investigator attended each transport and recorded any RE on a specifically designed data collection document. An RE was any mishap, even if not foreseen, that had the potential to cause the patient harm. A patient equipment number was assigned based on the number of pieces of equipment required during the transport. Poisson regression generated incidence rate ratios (IRRs) and determined risk factors for REs. RESULTS: Of 738 transports, 289 (39.1%, 95% CI 35.6% to 42.8%) had at least one RE. The total of 521 REs comprised 125 patient-related, 279 device-related and 117 line/catheter-related REs. The most common included trolley collisions (n=142), intravenous fluid line catching/tangling (n=93), agitation/aggression events (n=31) and cardiac monitoring issues (n=31). Thirty-four (6.5%) REs resulted in an undesirable patient outcome, most commonly distress and pain. Predisposing factors for REs included an equipment number ≥3 (IRR 5.68, 95% CI 3.95 to 8.17), transport to a general ward (IRR 2.68, 95% CI 2.12 to 3.39), hypertension (IRR 1.93, 95% CI 1.07 to 3.50), an abnormal temperature and a GCS<14. CONCLUSIONS: REs are common in transport of patients from the ED and can result in undesirable patient outcomes. Adequate pre-transfer preparation, especially securing equipment and lines, would result in a reduced risk.

Evolution of methodology and reporting of emergency medicine quantitative research over a 20-year period.

OBJECTIVE: We aimed to determine trends over time in article origin, and article and methodology characteristics. METHOD: We examined original research articles published every fifth year over a 20-year period (1997-2017) in six emergency medicine (EM) journals (Ann Emerg Med, Acad Emerg Med, Eur J Emerg Med, Emerg Med J, Am J Emerg Med, Emerg Med Australas). Explicit data extraction of 21 article characteristics was undertaken. These included regional contributions, specific article items and research methodology. RESULTS: 2152 articles were included. Over the study period, the proportional contributions from the USA and the UK steadily fell while those from Australasia, Europe and 'other' countries increased (p<0.001). All specific article items increased (p<0.01). Institutional Review Board/Ethics Committee approval and conflicts of interest were almost universal by 2017. There were substantial increases in the reporting of keywords and authorship contributions. The median (IQR) number of authors increased from 4 (2) in 1997 to 6 (3) in 2017 (p<0.001) and the proportion of female first authors increased from 24.3% to 34.2% (p<0.01). Multicentre and international collaborations, consecutive sampling, sample size calculations, inferential biostatistics and the reporting of CIs and p values all increased (p<0.001). There were decreases in the use of convenience sampling and blinding (p<0.001). The median (IQR) study sample size increased from 148 (470) to 349 (2225) (p<0.001). CONCLUSION: Trends over time are apparent within the EM research literature. The dominance in contributions from the US and UK is being challenged. There is more reporting of research accountability and greater rigour in both research methodology and results presentation.

Determination of the best early warning scores to predict clinical outcomes of patients in the emergency department.

OBJECTIVE: Early warning scores (EWS) are used to predict patient outcomes. We aimed to determine which of 13 EWS, based largely on emergency department (ED) vital sign data, best predict important clinical outcomes. METHOD: We undertook a prospective cohort study in a metropolitan, tertiary-referral ED in Melbourne, Australia (February-April 2018). Patient demographics, vital signs and management data were collected while the patients were in the ED and EWS were calculated using each EWS criteria. Outcome data were extracted from the medical record (2-day, 7-day and 28-day inhospital mortality, clinical deterioration within 2 days, intensive care unit (ICU) admission within 2 days, admission to hospital). Area under the receiver operator characteristic (AUROC; 95% CIs) curves were used to evaluate the predictive ability of each EWS for each outcome. RESULTS: Of 1730 patients enrolled, 690 patients were admitted to the study hospital. Most EWS were good or excellent predictors of 2-day mortality. When considering the point estimates, the VitalPac EWS was the most strongly predictive (AUROC: 0.96; 95% CI: 0.92 to 0.99). However, when considering the 95% CIs, there was no significant difference between the highest performing EWS. The predictive ability for 7-day and 28-day mortality was generally less. No EWS was a good predictor for clinical deterioration (AUROC range: 0.54-0.70), ICU admission (range: 0.51-0.72) or admission to hospital (range: 0.51-0.68). CONCLUSION: Several EWS have excellent predictive ability for 2-day mortality and have the potential to risk stratify patients in ED. No EWS adequately predicted clinical deterioration, admission to either ICU or the hospital.

Development of Acute Decompensated Heart Failure Among Hospital Inpatients: Incidence, Causes and Outcomes.

BACKGROUND: We aimed to investigate the incidence, precipitants, and outcomes of acute decompensated heart failure (ADHF) that develops during the inpatient stay. METHODS: We undertook a case-control study in the medical, oncology, surgical, and orthopaedic wards of a tertiary referral hospital (February-May, 2016). Patients aged ≥18 years who developed ADHF during their inpatient stay were enrolled as cases. One control patient was matched to each case by age, gender, presenting complaint/surgery performed and co-morbidities. Multivariate regression was employed to determine variables associated with ADHF. RESULTS: The incidence of ADHF was 1.0% of patients. Eighty cases were well-matched to 80 controls (p>0.05). ADHF precipitants comprised infection (30%), inappropriate intravenous (IV) fluid and medication management (23.8% and 8.8%, respectively), tachyarrhythmia (12.5%), ischaemic heart disease (8.8%), renal failure (1.3%), and other/unclear causes (15%). Three variables were associated with ADHF: not having English as the preferred language (OR 3.5, 95%CI 1.2-9.8), a history of ischaemic heart disease (OR 3.3, 95%CI 1.2-9.1), and the administration of >2000ml of IV fluid on the day before the ADHF (OR 8.3, 95%CI 1.5-48.0). The day before the ADHF, cases were administered significantly more IV fluids than controls (median 2,757.5 versus 975ml, p=0.001). Medication errors mostly related to failure to restart regular diuretics. Cases had significantly greater length of stay (median 15 versus 6 days, p<0.001) and mortality (12.5% versus 1.3%, p=0.01). CONCLUSIONS: New onset ADHF is common and a substantial proportion of cases are iatrogenic. Cases experience significantly increased length of hospital stay, morbidity, and mortality.

Analgesia in the emergency department: why is it not administered?

OBJECTIVE: Pain management in the ED is often suboptimal, with many patients not receiving analgesia. We aimed to determine why some patients refuse it, why others do not receive it, and whether these variables impact on patient satisfaction with their pain management. METHODS: We undertook a prospective, observational study in a large, Australian, tertiary referral ED (February-May 2017). A convenience sample of consecutive adult patients with a triage pain score of ≥4 were examined. Data were collected from the medical record and the treating nurses. At follow-up at least 48 hours postdischarge, patients were asked if they received analgesia in the ED (if not, then why not) and how satisfied they were with their pain management (very dissatisfied/dissatisfied/slightly dissatisfied/slightly satisfied/satisfied/very satisfied). The primary outcome was why patients refuse analgesia. RESULTS: Of the 651 enrolled patients, 171 (26.3%) did not receive analgesia; for 30 (17.5%), patients and their nurses agreed that analgesia was refused. Patients mainly refused analgesia because their pain was not bad enough, they had recent analgesia intake, and concerns about side effects and interactions. Patients who received analgesia were more likely to be 'very satisfied' with their pain management (difference in proportions 10.8%, 95% CI 2.1 to 19.4). The satisfaction of patients who refused analgesia and those who did not receive analgesia for other reasons did not differ. CONCLUSION: Patient refusal is the most common reason for patients not receiving analgesia. Analgesia receipt is associated with greater patient satisfaction. However, a patient's knowledge of their analgesia receipt status may be incorrect. Disregard of the reasons for patients not receiving analgesia may underestimate the number offered analgesia.

Complementary and alternative medicine use among paediatric emergency department patients.

AIM: To determine the period prevalence and nature of complementary and alternative medicine (CAM) use among paediatric emergency department (ED) patients and the perceptions of CAM among the CAM administrators. METHODS: A survey was undertaken in four Victorian EDs (January to September 2013). A convenience sample of parents/carers accompanying paediatric patients completed a self-administered questionnaire. The main outcome measures were CAM use and perceptions of CAM. RESULTS: The parents/carers of 883 patients participated. Three hundred eighty-eight (43.9%, 95% confidence interval (CI) 40.6-47.3) and 53 (6.0%, 95% CI 4.6-7.8) patients had taken a CAM within the previous 12 months and on the day of presentation, respectively. There were no gender differences between CAM users and non-users (P = 0.83). The use of CAM was significantly more common among older patients (P < 0.001), those with European ethnicity (P = 0.046) and among those with chronic disease (P < 0.01). Fish oil, garlic, chamomile and acidophilus were the most commonly used CAM. Only 4.4% of CAM use was reported to the ED doctor. There were reports of potentially dangerous CAM use (St John's wort, ginseng). Parents/carers who had administered CAM were more likely to report that CAMs are safe, drug free and could prevent illness (P < 0.01). In addition, a number of this group reported that CAMs are more effective than prescription medicines and safe when taken with prescription medicines. CONCLUSION: CAM use is common among paediatric ED patients although rarely reported to the ED doctor. Parents/carers who administer CAM have differing perceptions of CAM safety from those who do not.

Feasibility and outcomes of screening for cardiovascular risk factors in the emergency department.

OBJECTIVES: The present study aimed to determine the prevalence of undiagnosed and undertreated hypercholesterolaemia and hypertension (HT) among ED patients and to evaluate the effects of a formal referral back to the general practitioner (GP) for further management. METHODS: This was a cross-sectional study of ED patients with follow up, if indicated. Patients aged ≥35 years, without substantial illness or communication difficulties, were enrolled. Data were collected using a researcher-administered questionnaire, a point-of-care Accutrend® Plus System machine (Roche Diagnostic Australia Pty Ltd, Castle Hill, NSW, Australia) and digital sphygmomanometer. Patients with total cholesterol (TC) ≥6.0 mmol/L and/or BP ≥140/90 were given a referral letter and advised to consult their GP. The investigators made follow-up telephone calls 5 weeks later. RESULTS: Of 827 presentations, 534 patients were enrolled (mean age 56.7 ± 13.3 years, 300 [56.2%] male). One hundred and eleven patients (20.7%, 95% CI 17.5-24.5) had TC ≥6.0 mmol/L. Patients with/without elevated TC differed significantly (P < 0.05) in regard to age, gender, GP ownership and attendance, and previous screening. Sixty-six patients consulted with their GP. Thirty had their TC levels retested, 18 received dietary/lifestyle advice and four had lipid-lowering medication prescribed or adjusted. Ninety-six patients (18.0%, 95% CI 14.9-21.6) had HT. Whereas 53 consulted their GP, no action was taken in 43 cases. Investigations were ordered for three and nine had antihypertensive medication prescribed or adjusted. CONCLUSION: Substantial proportions of ED patients have undiagnosed and undertreated hypercholesterolaemia and/or HT. GP referral initiated interventions for many patients with hypercholesterolaemia, but fewer with HT. The ED has potential as a useful venue for the opportunistic screening of hypercholesterolaemia.

Recent caffeine ingestion reduces adenosine efficacy in the treatment of paroxysmal supraventricular tachycardia.

OBJECTIVES: Caffeine, an adenosine receptor blocker, should theoretically reduce adenosine efficacy in the treatment of paroxysmal supraventricular tachycardia (SVT). We aimed to determine the effect of recent caffeine ingestion on the likelihood of reversion of SVT with adenosine. METHODS: This was a multicenter, case-control study of adult patients with SVT treated with adenosine between September 2007 and July 2008. The primary endpoint was reversion to sinus rhythm (SR) after a 6-mg adenosine bolus, as a function of recent (within 2, 4, 6, and 8 hours) caffeine ingestion. Caffeine ingestion data were collected using a self-administered questionnaire. RESULTS: Of 68 patients enrolled, 52 (76.5%, 95% confidence interval [CI] = 64.4% to 85.6%) reverted after a 6-mg adenosine bolus. There were no significant differences in age, sex, or daily caffeine ingestion between patients who did and did not revert (p > 0.05). However, as a group, patients who did not revert had recently ingested significantly more caffeine (p < 0.05). If caffeine had been ingested less than 2 or 4 hours before the adenosine bolus, the odds of reversion to SR were significantly reduced (odds ratio [OR] = 0.18, 95% CI = 0.04 to 0.93; and OR = 0.14, 95% CI = 0.04 to 0.49, respectively). If caffeine had been ingested less than 6 or 8 hours before the adenosine, the odds of reversion were not reduced (OR = 0.31, 95% CI = 0.09 to 1.02; and OR = 0.31, 95% CI = 0.09 to 1.08, respectively). CONCLUSIONS: Ingestion of caffeine less than 4 hours before a 6-mg adenosine bolus significantly reduces its effectiveness in the treatment of SVT. An increased initial adenosine dose may be indicated for these patients.

Perceptions of surfboard riders regarding the need for protective headgear.

OBJECTIVE: To examine the use of protective headgear by surfers, their perceptions of its usefulness, and barriers to its use. METHODS: A researcher-administered questionnaire was used to undertake a cross-sectional survey of 646 surfboard riders at 8 popular surfing beaches in Victoria, Australia. The main outcome measures were rate of use of headgear, perceptions of head injury risk relative to a range of other activities, perceptions regarding headgear, and the reasons for not wearing headgear. RESULTS: Most surfers were men (90.2%), young (mean age 28.2 years), and experienced (mean years of surfing 11.6). Only 245 (38.0%, 95% CI 34.2-41.9) surfers considered the risk of head injury while surfing as moderate or high, and only 12 (1.9%, 95% CI 1.0-3.3) reported routine use of headgear. The surfers were more likely to believe that there was a higher risk of head injury in other sports and physical activities (P < .001). Although 475 surfers (73.8%, 95% CI 70.2-77.1) thought that surfers who wear headgear are less likely to become injured, 400 (62.1%, 95% CI 58.2-65.9) reported that headgear restricted surfing performance and that they would rather surf without it. The main reasons for not wearing headgear were "no need," discomfort, claustrophobia, and effects upon the senses and balance. CONCLUSIONS: Although most surfers acknowledge some risk of head injury, headgear is rarely used and barriers to its use are apparent. Research is required to clarify the risk of head injury among surfers and the effectiveness of headgear in reducing injury risk. Until this evidence is available, educational initiatives, improved headgear design, and profile within the surfing culture would be required to increase rates of wearing headgear.