Safety of telephone consultation for "non-serious" emergency ambulance service patients.

OBJECTIVE: To assess the safety of nurses and paramedics offering telephone assessment, triage, and advice as an alternative to immediate ambulance dispatch for emergency ambulance service callers classified by lay call takers as presenting with "non-serious" problems (category C calls). DESIGN: Data for this study were collected as part of a pragmatic randomised controlled trial reported elsewhere. The intervention arm of the trial comprised nurse or paramedic telephone consultation using a computerised decision support system to assess, triage, and advise patients whose calls to the emergency ambulance service had been classified as "non-serious" by call takers applying standard priority dispatch criteria. A multidisciplinary expert clinical panel reviewed data from ambulance service, accident and emergency department, hospital inpatient and general practice records, and call transcripts for patients triaged by nurses and paramedics into categories that indicated that dispatch of an emergency ambulance was unnecessary. All cases for which one or more members of the panel rated that an emergency ambulance should have been dispatched were re-reviewed by the entire panel for an assessment of the "life risk" that might have resulted. SETTING: Ambulance services in London and the West Midlands, UK. STUDY POPULATION: Of 635 category C patients assessed by nurses and paramedics, 330 (52%) cases that had been triaged as not requiring an emergency ambulance were identified. MAIN OUTCOME MEASURES: Assessment of safety of triage decisions. RESULTS: Sufficient data were available from the routine clinical records of 239 (72%) subjects to allow review by the specialist panel. For 231 (96.7%) sets of case notes reviewed, the majority of the panel concurred with the nurses' or paramedics' triage decision. Following secondary review of the records of the remaining eight patients, only two were rated by the majority as having required an emergency ambulance within 14 minutes. For neither of these did a majority of the panel consider that the patient would have been at "life risk" without an emergency ambulance being immediately dispatched. However, the transcripts of these two calls indicated that the correct triage decision had been communicated to the patient, which suggests that the triage decision had been incorrectly entered into the decision support system. CONCLUSIONS: Telephone advice may be a safe method of managing many category C callers to 999 ambulance services. A clinical trial of the full implementation of this intervention is needed, large enough to exclude the possibility of rare adverse events.

On-scene alternatives for emergency ambulance crews attending patients who do not need to travel to the accident and emergency department: a review of the literature.

With rising demand and recognition of the variety of cases attended by emergency ambulance crews, services have been considering alternative ways of providing non-urgent care. This paper describes and appraises the research literature concerning on-scene alternatives to conveyance to an emergency department, focusing on the: (1) profile and outcomes of patients attended but not conveyed by emergency crews; (2) triage ability of crews; (3) effectiveness and safety of protocols that allow crews to convey patients to alternative receiving units or to self care. The literature search was conducted through standard medical databases, supplemented with manual searches. Very few "live" studies were identified, and fewer still that included a control group. Findings indicated a complex area, with the introduction of protocols allowing crews to leave patients at scene carrying clinical risk. Robust research evidence concerning alternatives to current emergency care models is needed urgently to inform service and practice development.

Does the use of the Advanced Medical Priority Dispatch System affect cardiac arrest detection?

BACKGROUND: Cardiac arrest is the most widely recognised prehospital event that early intervention can directly affect. Chance of survival from this event decreases every minute that passes without treatment. To deliver a rapid ambulance response to these patients the early detection of cardiac arrest by control room staff is crucial. To achieve this, the London Ambulance Service (LAS) uses the Advanced Medical Priority Dispatch System. What impact has AMPDS had on identifying patients in cardiac arrest? Does compliance with AMPDS protocol influence the identification of patients in cardiac arrest? METHODS: A two stage study was undertaken. The first, compared cases coded as "cardiac arrest" and found by the responding ambulance to be in cardiac arrest before the implementation of AMPDS. This was compared with cases triaged as "cardiac arrest" and found to be in cardiac arrest across three years after AMPDS implementation. The second stage compared AMPDS compliance, over a 32 month period against the percentage of cardiac arrest calls that were found to be cardiac arrest upon the ambulance arrival. The correlation coefficient was calculated and analysed for statistical significance. FINDINGS: AMPDS resulted in a 200% rise in the number of patients accurately identified as suffering from cardiac arrest. A relation was identified between identification and AMPDS compliance (r(2) = 0.65, p = 0.001). DISCUSSION: The implementation of AMPDS increased accurate identification of patients in cardiac arrest. Additionally, the relation between factors identified suggests compliance with protocol is an important factor in the accurate recognition of patient conditions.

Computer assisted assessment and advice for "non-serious" 999 ambulance service callers: the potential impact on ambulance despatch.

OBJECTIVE: To investigate the potential impact for ambulance services of telephone assessment and triage for callers who present with non-serious problems (Category C calls) as classified by ambulance service call takers. DESIGN: Pragmatic controlled trial. Calls identified using priority dispatch protocols as non-serious were allocated to intervention and control groups according to time of call. Ambulance dispatch occurred according to existing procedures. During intervention sessions, nurses or paramedics within the control room used a computerised decision support system to provide telephone assessment, triage and, if appropriate, offer advice to permit estimation of the potential impact on ambulance dispatch. SETTING: Ambulance services in London and the West Midlands. SUBJECTS: Patients for whom emergency calls were made to the ambulance services between April 1998 and May 1999 during four hour sessions sampled across all days of the week between 0700 and 2300. MAIN OUTCOME MEASURES: Triage decision, ambulance cancellation, attendance at an emergency department. RESULTS: In total, there were 635 intervention calls and 611 controls. Of those in the intervention group, 330 (52.0%) were triaged as not requiring an emergency ambulance, and 119 (36.6%) of these did not attend an emergency department. This compares with 55 (18.1%) of those triaged by a nurse or paramedic as requiring an ambulance (odds ratio 2.62; 95% CI 1.78 to 3.85). Patients triaged as not requiring an emergency ambulance were less likely to be admitted to an inpatient bed (odds ratio 0.55; 95% CI 0.33 to 0.93), but even so 30 (9.2%) were admitted. Nurses were more likely than paramedics to triage calls into the groups classified as not requiring an ambulance. After controlling for age, case mix, time of day, day of week, season, and ambulance service, the results of a logistic regression analysis revealed that this difference was significant with an odds ratio for nurses:paramedics of 1.28 (95% CI 1.12 to 1.47). CONCLUSIONS: The findings indicate that telephone assessment of Category C calls identifies patients who are less likely to require emergency department care and that this could have a significant impact on emergency ambulance dispatch rates. Nurses were more likely than paramedics to assess calls as requiring an alternative response to emergency ambulance despatch, but the extent to which this relates to aspects of training and professional perspective is unclear. However, consideration should be given to the acceptability, reliability, and cost consequences of this intervention before it can be recommended for full evaluation.

Differences in aerosol output and airways responsiveness between the DeVilbiss 40 and 45 hand held nebulisers.

BACKGROUND: The DeVilbiss 40 glass hand held nebulisers have been widely used for airways responsiveness testing in epidemiological surveys of asthma. These nebulisers have been superseded in some recent studies by the DeVilbiss 45 plastic hand held nebulisers with the assumption that they are interchangeable. This study compared the aerosol outputs of the DeVilbiss 40 and DeVilbiss 45 nebulisers and investigated whether there was any difference in the in vivo measurements of airways responsiveness when using the two nebuliser types. METHODS: The aerosol output of six DeVilbiss 40 and six DeVilbiss 45 nebulisers was calculated by weight loss per actuation, the usual method of calibrating nebuliser output, and compared with the true amount of aerosol obtained measured by a flouride tracer technique. Airways responsiveness was measured twice in 13 asthmatic patients under identical conditions by the Yan protocol using DeVilbiss 40 and 45 nebulisers in random order. RESULTS: Weight loss overestimated the true aerosol output of both types of nebulisers. Weight loss was similar for the DeVilbiss 40 and 45 nebulisers but the true aerosol output of the DeVilbiss 45 was nearly twice that of the DeVilbiss 40 nebuliser. The geometric mean PD20 values with the DeVilbiss 40 nebuliser was a mean 1.7 doubling doses of histamine higher than that obtained with the DeVilbiss 45 nebuliser. CONCLUSIONS: The DeVilbiss 40 and 45 nebulisers should not be used interchangeably for airways responsiveness testing merely because their outputs based on weight loss are similar. Artefactual differences in the prevalence rates of airways responsiveness could occur in longitudinal studies if a change was inadvertently made from using DeVilbiss 40 to DeVilbiss 45 nebulisers.