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Updated: Jun 25, 2026
Simultaneous Electrocardiography Recording and Invasive Blood Pressure Measurement in Rats
Published on: January 31, 2019
Invasive arterial blood pressure monitoring in an out-of-hospital setting: an observational study
1Service d'Anesthésie Réanimation et SAMU 94, Henri Mondor University Hospital, Créteil, France.
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.
Conclusion:
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.
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01:21Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
01:15Assessment of blood pressure in brachial artery(one-step method)
Prepare for the Procedure:
01:10Pre-Procedural Guidelines for Assessing Blood Pressure
01:30Equipments Used To Measure Blood Pressure
This invasive approach involves cannulating a peripheral artery. During each cardiac contraction, pressure generates mechanical motion within the catheter, transmitted through rigid, fluid-filled tubing to a transducer. This transducer converts mechanical motion into electrical signals displayed as waveforms on a monitor. An automatic flushing system prevents blood backflow. Due to the potential risk of unexpected arterial blood loss, this method is primarily used in intensive...
01:28Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
01:23Assessment of blood pressure in brachial artery(two-step method)