Agreements between mean arterial pressure from radial and femoral artery measurements in refractory shock patients

Abstract

Radial and femoral artery catheterization is the most common procedure for monitoring patients with shock. However, a disagreement in mean arterial pressure (MAP) between the two sites has been reported. Hence, the aim of this study was to compare the MAP from the radial artery (MAPradial) with that of the femoral artery (MAPfemoral) in patients with refractory shock. A prospective study was conducted in the medical intensive care unit. The radial and femoral were simultaneously measured MAP in the patients every hour, for 24 h. In total, 706 paired data points were obtained from 32 patients. MAPradial strongly correlated with MAPfemoral (r = 0.89, p < 0.0001). However, overall MAPradial was significantly lower than MAPfemoral 7.6 mmHg. The bias between MAPradial and MAPfemoral was − 7.6 mmHg (95% limits of agreement (LOA), − 24.1 to 8.9). In the subgroup of patients with MAPradial < 65 mmHg, MAPradial moderately correlated with MAPfemoral (r = 0.63) and the bias was increased to − 13.0 mmHg (95% LOA, − 28.8 to 2.9). There were 414 (58.6%) measurements in which the MAP gradient between the two sites was > 5 mmHg. In conclusion, the radial artery significantly underestimated MAP compared with the femoral artery in patients with refractory shock.

Expert consensus on blood pressure management in critically ill patients

“…A prospective study in 2022 that included 32 patients with refractory shock found that the MAP in the radial artery was 7.6 mmHg lower than in the femoral artery. [15] Similarly, in a prospective study of critically ill patients with sepsis, the MAP of the radial artery was lower than that of the femoral artery (66±2.2 mmHg vs. 81±2.5 mmHg) when high-dose norepinephrine was used. [16] Therefore, when administering large doses of vasoactive agents, central arteries (such as the femoral artery) can be used for invasive blood pressure monitoring.…”

Accuracy of Noninvasive Blood Pressure Monitoring in Critically Ill Adults

“…These trends align with typical clinical expectations as they are scenarios believed to compromise the accuracy of cuff BP measurements. 14,23 The radial artery and catheter are narrower in diameter than their femoral counterparts which may in part explain more divergent measurements; however, it is worth nothing the majority of measurements were made with radial catheters. Importantly, while these variables are statistically significant predictors in a regression model, the adjusted odds ratios are low indicating only modest ability of these factors to predict measurement disagreement.…”

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

“…The basic features of the included studies are summarized in Table 1; and Supplemental Table 2 (http:// links.lww.com/CCX/B343). The earliest article was published in 1987 (29), and the latest article was published in 2022 (6)(7)(8). Twenty-three studies compared the femoral artery with the radial artery, whereas one study compared the femoral artery with the brachial artery.…”

“…Earlier studies have shown variable results regarding the concordance of blood pressure readings from different arterial sites in high-risk surgical and critically ill patients. Some studies found a good correlation between these measurements, while others observed genuine differences in systolic blood pressure (SBP) and mean arterial pressure (MAP) between central and peripheral sites (6–29). This disparity has the potential to influence clinical decision-making and patient outcomes as the accuracy of invasive blood pressure monitoring is crucial in determining the stability of the circulatory system, perfusion to major organs and hence guide the need for interventions.…”