Effect of slow and deep breathing on clinical blood pressures and a pilot study on its effectiveness in pregnant women
Nwobodo Nzeribe, Nnenna Harmony
mesheuropmc: cardiovascular diseases | circulatory and respiratory physiology
There is no study investigating the effect of deep breathing on clinical BPs measured simultaneously by manual auscultatory and automatic techniques. This research aimed to provide scientific evidence on the comparison of the effect of deep breathing on manual auscultatory BPs and automatic BPs, and will also preliminarily investigate the effect of deep breathing on pregnant subjects.\ud The first study involved thirty-nine healthy subjects. The manual systolic and diastolic BPs (SBP and DBP) and MAP were obtained from each subject under resting and deep breathing conditions. During the manual measurement, the oscillometric cuff pressure was simultaneously recorded to determine automated SBP, MAP and DBP, which were cuff pressures corresponding to 50%, 100% and 70% of the waveform envelope, fitted to the oscillometric pulse amplitude. Finally, the effect of deep breathing on both manual and automated BPs were compared.\ud Experimental results showed that deep breathing significantly (all p<0.001) decreased manual SBP, MAP and DBP by 3.5, 3.7 and 3.7 mmHg, respectively, when compared with the resting condition. Automated SBP, MAP and DBP were also decreased significantly (all p<0.001) by 2.0, 3.4 and 3.2 mmHg, respectively. In addition, it is observed that 56%, 62% and 67% of subjects showed SBP, MAP and DBP reductions with deep breathing in both manual auscultatory and automatic oscillometric techniques.\ud The second study involved twenty pregnant subjects. Automated SBP and DBP were measured from each subject at different time points (before, during and after deep breathing). The automated BPs were then compared between the different time points. Experimental results showed that deep breathing decreased automated SBP and DBP significantly (p<0.001) by 6.4 and 4.8 mmHg. Similarly, automated SBP and DBP measured after deep breathing were also significantly (p<0.001) decreased by 5.6 and 4.5 mmHg, respectively. Over 70% of the subjects had either SBP or DBP reduction during and after deep breathing.\ud In conclusion, both manual and automatic BPs were significantly decreased with deep breathing. Over half of the normal healthy subjects achieved significant BP reductions with deep breathing in both manual and automatic techniques. Additionally, it has been demonstrated by our pilot study that deep breathing can be potentially used as a management tool to reduce BPs for some pregnant women.