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Contrast-Enhanced Subharmonic Aided Pressure Estimation (SHAPE) Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension
Published on: December 5, 2020
The effect of different reference transducer positions on intra-abdominal pressure measurement: a multicenter
Jan J De Waele1, Inneke De Laet, Bart De Keulenaer
1Surgical Intensive Care Unit, Ghent University Hospital, De Pintelaan 185, 9000, Gent, Belgium. jan.dewaele@UGent.be
Objective:
To investigate the effect of different reference transducer positions on intra-abdominal pressure (IAP) measurement. Three reference levels were studied: the symphysis pubis; the phlebostatic axis; and the midaxillary line at the level of the iliac crest.
Design:
Prospective cohort study.
Setting:
The intensive care units of participating hospitals
Patients And Participants:
One hundred thirty-two critically ill patients at risk for intra-abdominal hypertension (IAH).
Interventions:
In each patient, three sets of IAP measurements were obtained in the supine position, using the different reference levels. The IAP measurements obtained at the different reference levels were compared using a paired t-test and Bland-Altman statistics were calculated.
Measurements And Results:
IAP(phlebostatic) (9.9 +/- 4.67 mmHg) and IAP(pubis) (8.4 +/- 4.60 mmHg) were significantly lower that IAP(midax) (12.2 +/- 4.66 mmHg; p < 0.0001 for both comparisons). The bias between the IAP(midax) and IAP(pubis) was 3.8 mmHg (95% CI 3.5-4.1) and 2.3 mmHg (95% CI 1.9-2.6) between the IAP(midax) and the IAP(phlebostatic). The precision was 3.03 and 3.40, respectively.
Conclusions:
In the supine position, IAP(midax) is higher than both IAP(phlebostatic) and IAP(pubis), differences found to be clinically significant; therefore, the symphysis pubis or phlebostatic axis reference lines are not interchangeable with the midaxillary level.
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