Study of agreement of aortic, radial and femoral blood pressures during aortic endografting

Comparison of Central and Peripheral Arterial Blood Pressure Gradients in Critically Ill Patients: A Systematic Review and Meta-Analysis

OBJECTIVES

Measurement of blood pressure taken from different anatomical sites, are often perceived as interchangeable, despite them representing different parts of the systemic circulation. We aimed to perform a systematic review and meta-analysis on blood pressure differences between central and peripheral arterial cannulation in critically ill patients.

DATA SOURCES

We searched MEDLINE, Cochrane Central Register of Controlled Trials, and Embase from inception to December 26, 2023, using Medical Subject Headings (MeSH) terms and keywords.

STUDY SELECTION

Observation study of adult patients in ICUs and operating rooms who underwent simultaneous central (femoral, axillary, or subclavian artery) and peripheral (radial, brachial, or dorsalis pedis artery) arterial catheter placement in ICUs and operating rooms.

DATA EXTRACTION

We screened and extracted studies independently and in duplicate. We assessed risk of bias using the revised Quality Assessment for Studies of Diagnostic Accuracy tool.

DATA SYNTHESIS

Twenty-four studies that enrolled 1598 patients in total were included. Central pressures (mean arterial pressure [MAP] and systolic blood pressure [SBP]) were found to be significantly higher than their peripheral counterparts, with mean gradients of 3.5 and 8.0 mm Hg, respectively. However, there was no statistically significant difference in central or peripheral diastolic blood pressure (DBP). Subgroup analysis further highlighted a higher MAP gradient during the on-cardiopulmonary bypass stage of cardiac surgery, reperfusion stage of liver transplant, and in nonsurgical critically ill patients. SBP or DBP gradient did not demonstrate any subgroup specific changes.

CONCLUSIONS

SBP and MAP obtained by central arterial cannulation were higher than peripheral arterial cannulation; however, clinical implication of a difference of 8.0 mm Hg in SBP and 3.5 mm Hg in MAP remains unclear. Our current clinical practices preferring peripheral arterial lines need not change.

A systematic review of invasive, high-fidelity pressure studies documenting the amplification of blood pressure from the aorta to the brachial and radial arteries

It is commonly accepted that systolic blood pressure (SBP) is significantly higher in the brachial/radial artery than in the aorta while mean (MBP) and diastolic (DBP) pressures remain unchanged. This may have implications for outcome studies and for non-invasive devices calibration. We performed a systematic review of invasive high-fidelity pressure studies documenting BP in the aorta and brachial/radial artery. We selected articles published prior to July 2015. Pressure amplification (Amp = peripheral minus central pressure) was calculated (weighted mean). The six studies retained (n = 294, 76.5% male, mean age 63.5 years) mainly involved patients with suspected coronary artery disease (CAD). In two studies at the aortic/brachial level (n = 64), MBP and DBP were unchanged (MPAmp = 0.1 mmHg, DPAmp = -1.3 mmHg), while SBP increased (SPAmp = 4.2 mmHg; relative amplification = 3.1%). In four studies in which MBP was not documented (n = 230), brachial DBP remained unchanged and SBP increased (SPAmp = 6.6 mmHg; 4.9%). One of these four studies also reported radial SBP and DBP, not MBP (n = 12). Few high-fidelity pressure studies were found, and they have been performed mainly in elderly male patients with suspected CAD. Counter to expectations, the mean amplification of SBP from the aorta to brachial artery was < 5%. Further studies on SPAmp phenotypes (positive, null, negative) are advocated. Non-invasive device calibration assumptions were confirmed, namely unchanged MBP and DBP from the aorta to the brachial artery. Data did not allow for firm conclusions on the amount of BP changes from the aorta to the radial artery, and from the aorta to the brachial/radial arteries in other populations.

Pressure difference between radial and femoral artery pressure in minimally invasive cardiac surgery using retrograde perfusion

Objective:

To investigate whether radial artery pressure is a reliable surrogate measure of central arterial pressure as approximated by femoral artery pressure in minimally invasive cardiac surgery with retrograde perfusion via femoral cannulation.

Method:

Fifty-two consecutive patients undergoing minimally invasive cardiac surgery were prospectively included in this study. Cardiopulmonary bypass was established via a femoral artery cannulation and femoral vein. Radial and femoral arterial pressures were recorded continuously, and the pressure differential between them was calculated for both systolic and mean arterial pressures. The agreement between measurements from the two arteries was compared using Bland–Altman plots. An interval of 95% limits of agreement of less than 20 mm Hg was set as satisfactory agreement.

Results:

Average age was 65 ± 14 years. With respect to systolic arterial pressure, 28 patients (54%) had a peak pressure differential between radial and femoral arteries ⩾20 mm Hg. With respect to mean arterial pressure, only five patients (9%) had a peak pressure differential ⩾20 mm Hg. The pressure differential changed with time. Pressure differential in systolic arterial pressure was 5 ± 8 mm Hg until aortic declamping, then increased to a peak of 23 ± 16 mm Hg when cardiopulmonary bypass was turned off. The femoral systolic arterial pressures were significantly greater than radial systolic arterial pressures from time of aortic declamping to 20 min after cardiopulmonary bypass. The Bland–Altman plots revealed large biases and poor agreement in this period.

Conclusion:

Radial and femoral systolic artery pressure readings can differ significantly in minimally invasive cardiac surgery with retrograde perfusion. Intraoperative arterial pressure management based solely on radial systolic arterial pressure readings should be avoided.

Optimal perioperative management of arterial blood pressure

Perioperative blood pressure management is a key factor of patient care for anesthetists, as perioperative hemodynamic instability is associated with cardiovascular complications. Hypertension is an independent predictive factor of cardiac adverse events in noncardiac surgery. Intraoperative hypotension is one of the most encountered factors associated with death related to anesthesia. In the preoperative setting, the majority of antihypertensive medications should be continued until surgery. Only renin-angiotensin system antagonists may be stopped. Hypertension, especially in the case of mild to moderate hypertension, is not a cause for delaying surgery. During the intraoperative period, anesthesia leads to hypotension. Hypotension episodes should be promptly treated by intravenous vasopressors, and according to their etiology. In the postoperative setting, hypertension predominates. Continuation of antihypertensive medications and postoperative care may be insufficient. In these cases, intravenous antihypertensive treatments are used to control blood pressure elevation.