title: Prevalence and predictors of hospital prealerting in acute stroke: a mixed methods study.
abstract: BACKGROUND
  Thrombolysis can significantly reduce the burden of stroke but the time window for safe and effective treatment is short. In patients travelling to hospital via ambulance, the sending of a 'prealert' message can significantly improve the timeliness of treatment.
  
  
  OBJECTIVE
  Examine the prevalence of hospital prealerting, the extent to which prealert protocols are followed and what factors influence emergency medical services (EMS) staff's decision to send a prealert.
  
  
  METHODS
  Cohort study of patients admitted to two acute stroke units in West Midlands (UK) hospitals using linked data from hospital and EMS records. A logistic regression model examined the association between prealert eligibility and whether a prealert message was sent. In semistructured interviews, EMS staff were asked about their experiences of patients with suspected stroke.
  
  
  RESULTS
  Of the 539 patients eligible for this study, 271 (51%) were recruited. Of these, only 79 (29%) were eligible for prealerting according to criteria set out in local protocols but 143 (53%) were prealerted. Increasing number of Face, Arm, Speech Test symptoms (1 symptom, OR 6.14, 95% CI 2.06 to 18.30, p=0.001; 2 symptoms, OR 31.36, 95% CI 9.91 to 99.24, p<0.001; 3 symptoms, OR 75.84, 95% CI 24.68 to 233.03, p<0.001) and EMS contact within 5 h of symptom onset (OR 2.99, 95% CI 1.37 to 6.50 p=0.006) were key predictors of prealerting but eligibility for prealert as a whole was not (OR 1.92, 95% CI 0.85 to 4.34 p=0.12). In qualitative interviews, EMS staff displayed varying understanding of prealert protocols and described frustration when their interpretation of the prealert criteria was not shared by ED staff.
  
  
  CONCLUSIONS
  Up to half of the patients presenting with suspected stroke in this study were prealerted by EMS staff, regardless of eligibility, resulting in disagreements with ED staff during handover. Aligning the expectations of EMS and ED staff, perhaps through simplified prealert protocols, could be considered to facilitate more appropriate use of hospital prealerting in acute stroke.
authors.affiliation: Nuffield Department of Primary Care Health Sciences, NIHR School for Primary Care Research, University of Oxford, Oxford, Oxfordshire, UK.
authors.forename: J P
authors.initials: JP
authors.lastname: Sheppard
authors.affiliation: Primary Care Clinical Sciences, NIHR School for Primary Care Research, University of Birmingham, Birmingham, West Midlands, UK.
authors.forename: A
authors.initials: A
authors.lastname: Lindenmeyer
authors.affiliation: Department of Public Health, NHS Lanarkshire, Bothwell, UK.
authors.forename: R M
authors.initials: RM
authors.lastname: Mellor
authors.affiliation: Department of Public Health, NHS Lanarkshire, Bothwell, UK.
authors.forename: S
authors.initials: S
authors.lastname: Greenfield
authors.affiliation: Primary Care Unit, University of Cambridge, Cambridge, Cambridgeshire, UK.
authors.forename: J
authors.initials: J
authors.lastname: Mant
authors.affiliation: Faculty of Health, Social Care and Education, St George's, University of London & Kingston University, London, UK.
authors.forename: T
authors.initials: T
authors.lastname: Quinn
authors.affiliation: West Midlands Ambulance Service NHS Trust, Regional Ambulance Headquarters, Dudley, West Midlands, UK.
authors.forename: A
authors.initials: A
authors.lastname: Rosser
authors.affiliation: Heart of England NHS Foundation Trust, Birmingham, West Midlands, UK.
authors.forename: D
authors.initials: D
authors.lastname: Sandler
authors.affiliation: Queen Elizabeth Hospital Birmingham Elderly Care, University Hospitals Birmingham NHS Foundation Trust, Birmingham, West Midlands, UK.
authors.forename: D
authors.initials: D
authors.lastname: Sims
authors.affiliation: West Midlands Ambulance Service NHS Trust, Regional Ambulance Headquarters, Dudley, West Midlands, UK.
authors.forename: M
authors.initials: M
authors.lastname: Ward
authors.affiliation: Nuffield Department of Primary Care Health Sciences, NIHR School for Primary Care Research, University of Oxford, Oxford, Oxfordshire, UK.
authors.forename: R J
authors.initials: RJ
authors.lastname: McManus
mesh_terms: D000368:Aged; D004631:Emergency Medical Service Communication Systems; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D015995:Prevalence; D012189:Retrospective Studies; D020521:Stroke / Q000453:epidemiology / Q000628:therapy*; D015912:Thrombolytic Therapy; D013997:Time Factors; D014187:Transportation of Patients; D016896:Treatment Outcome
keywords: emergency department; prehospital care