Impact of ambulance transportation on resource use in the emergency department.
OBJECTIVE
To determine how ambulance transportation is associated with resource use in the emergency department (ED).


METHODS
A retrospective administrative database review of patient visits to a Montreal tertiary care hospital ED in one year (April 2000-March 2001). Measures of resource use included ED length of stay, admission to the hospital, and whether consultations and radiology/imaging tests (excluding plain-film x-rays) were ordered from the ED.


RESULTS
During the study period, 39,674 patients made 59,142 visits to the ED. Ambulance transportation was used for 15.6% of these ED visits. Compared with non-ambulance visits, ambulance visits were more likely to be made by older patients (mean age: 68 vs. 47 years), to be made by females (59% vs. 55%), to have a greater triage urgency score (mean on 1-5 scale, with 1 most urgent: 2.7 vs. 3.9), and to occur after office hours, 5 PM to 9 AM (47% vs. 43%). Ambulance visits were also more likely than non-ambulance visits to result in: a longer length of stay (mean: 13.3 hours [95% CI = 13.0 to 13.6] vs. 5.9 [95% CI = 5.8 to 6.0]), hospital admission (40% vs. 10%) (odds ratio [OR]: 5.94 [95% CI = 5.59 to 6.33]), consultations (56% vs. 20%) (OR: 5.15 [95% = 4.86 to 5.45]), and radiology/imaging tests (20% vs. 12%) (OR: 1.93 [95% CI = 1.81 to 2.07]). In multivariate models that adjusted for the effects of age, gender, triage urgency, and temporal factors, ambulance transportation maintained its association with greater resource use.


CONCLUSIONS
This preliminary study indicates that patients arriving at the ED by ambulance use significantly more resources than their walk-in counterparts.
McGill University, Montreal, Quebec, Canada.
Adrian
A
Marinovich
Jonathan
J
Afilalo
Marc
M
Afilalo
Antoinette
A
Colacone
Bernard
B
Unger
Claudine
C
Giguère
Ruth
R
Léger
Xiaoqing
X
Xue
Jean-François
JF
Boivin
Elizabeth
E
MacNamara
D017677:Age Distribution; D000368:Aged; D000552:Ambulances / Q000706:statistics & numerical data*; D003952:Diagnostic Imaging / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D015276:Health Care Rationing / Q000706:statistics & numerical data*; D019538:Health Care Surveys; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010343:Patient Admission / Q000706:statistics & numerical data; D011792:Quebec; D012189:Retrospective Studies; D017678:Sex Distribution; D014218:Triage / Q000706:statistics & numerical data; D014600:Utilization Review