Validity Of Palpation To Measure Arterial Occlusion Pressure In The Upper And Lower Limb

For implementation of exercise with blood flow restriction (BFR) it is recommended that cuff pressures be based on arterial occlusion pressure (AOP). However, clinicians, coaches, and athletes may not have access to the necessary equipment for directly assessing AOP (i.e., Doppler ultrasound, handheld Doppler). Palpation, a method of detecting blood flow by simply feeling the pulse with the fingers, could serve as a practical alternative to measuring AOP that would require no equipment. However, there is no data supporting the validity of this method. PURPOSE: The purpose of this study was to investigate the validity of manual palpation to measure AOP in both the upper and lower limbs. METHODS: Nine normotensive healthy adults (age 25 ± 5) underwent measures of upper and lower-limb AOP in a supine position by applying a 5 cm and 12 cm wide pneumatic cuff to the upper and lower-limbs, respectively. For both limbs, AOP was assessed simultaneously via handheld Doppler and manual palpation by separate investigators at the radial and posterior tibial arteries. Investigators wore sound-canceling headphones and were visually blinded to one another. The degree of agreement between AOP values measured via Doppler and palpation was assessed using Bland-Altman limits of agreement (LoA). To statistically test the equivalence of values we utilized a two one-sided paired t-test (ɑ = 0.05) with an equivalence region equal to 10% of the mean Doppler AOP. RESULTS: In the upper-limb, the mean difference between palpation (155 ± 17 mmHg) and Doppler (167 ± 20 mmHg) AOP values was -2.8 mmHg. The upper and lower 95% LoA were 11.2 mmHg and -17.0 mmHg. Values obtained via Doppler and palpation were equivalent (p < 0.05). In the lower-limb, the mean difference between palpation (138 ± 11 mmHg) and Doppler (145 ± 14 mmHg) values was -7.3 mmHg. The upper and lower 95% LoA were 15.9 mmHg and -30.8 mmHg. Values obtained via Doppler and palpation were not equivalent (p = 0.07). CONCLUSION: Our results indicate that palpation is a valid way to measure AOP in the upper limbs. Palpation does not provide valid measures in the lower-limb, however, measures may still be practically acceptable for selecting exercising cuff pressures. Accordingly, arterial palpation allows for the implementation of exercise with BFR without the need for specialized equipment.