Invasive arterial blood pressure monitoring in an out-of-hospital setting: an observational study.
BACKGROUND
Non-invasive arterial blood pressure measurement is often inaccurate in emergency unstable patients. A study was undertaken to assess the feasibility of out-of-hospital intra-arterial catheterisation in haemodynamically unstable patients and to evaluate the correlation between invasive and non-invasive arterial pressure values.


METHODS
In this prospective 2-year observational study conducted by mobile emergency medical units, the success rate of arterial catheterisation was calculated and blood pressure values measured invasively and non-invasively after successful catheterisation were compared.


RESULTS
94 patients were included. The success rate for catheterisation (44 radial access, 50 femoral access) was 86% (95% CI 79% to 93%). Bias and precision in invasive versus non-invasive comparisons were -0.1, 38 mm Hg for systolic pressure and 4.2, 27 mm Hg for diastolic pressure. Values differed by more than 20 mm Hg in over 40% of patients. Invasive measurement led to 79 changes in vasoactive treatment in 51 patients.


CONCLUSIONS
Emergency out-of-hospital invasive arterial blood pressure monitoring in haemodynamically unstable patients is highly feasible. Discrepancies between invasive and non-invasive measurements are common and highlight the value of early out-of-hospital monitoring.
Sende
J
J
Service d'Anesthésie Réanimation et SAMU 94, Henri Mondor University Hospital, Créteil, France.
Jabre
P
P
Leroux
B
B
Penet
C
C
Lecarpentier
E
E
Khalid
M
M
Margenet
A
A
Marty
J
J
Combes
X
X
D000368:Aged; D001795:Blood Pressure Determination / Q000379:methods*; D001930:Brain Injuries / Q000628:therapy; D002406:Catheterization, Peripheral / Q000379:methods*; D016009:Chi-Square Distribution; D004632:Emergency Medical Services / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006323:Heart Arrest / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D020521:Stroke / Q000628:therapy