Effect of Patient Position with Spinal Anesthesia on the Heart Rate, Arterial Blood Pressure and Arterial Blood Gas Change

Hong, Mi Jung; Joo, Jae Sik; Kim, Young Joo; Park, Hyun Hae; Kang, Seung Ho

Abstract

BACKGROUND
Anorectal procedures are performed in the prone jack-knife or lithotomy position. The effect of lithotomy and prone jack-knife position on the heart rate, arterial blood pressure and arterial blood gas has not been compaired.
METHODS
39 consecutive patients who underwent surgery for anorectal disease were performed saddle block. They were randomly classified into two groups: prone jack-knife position(J; n=19) and lithotomy position(L; n=20); patients with cardiovascular disease were excluded. The two groups were well matched for age, gender, weight and height. After spinal anesthesia, heart rate(HR), blood pressure(BP), and arterial blood gases(ABG) including pH, PaO2, PaCO2, HCO3- were measured in the supine position to establish a base line. After position change to either jack-knife or lithotomy, HR, BP(systolic, mean and diastolic) at 10, 20, and 30 minutes and ABG at 20minutes were measured again in each group. The two groups were then compared and any changes were recorded. Premedication was not perfomed in both group. Statistical analysis was performed by Mann-Whitney U test; significance was set at P <0.05.
RESULTS
There were no differences between the two groups in terms of baseline HR, BP and ABG. However, HR at 10, 20 and 30 minutes after position change in the L group were increased compared with those of J group(deltaHR (number/minute) at 10 minutes: +3.2+/-7.0(L) versus - 2.8+/-4.9(J), P <0.05, 20 minutes: +5.6+/-7.4(L) versus - 1.8+/-5.2(J), P <0.05, 30 minutes: +6.4+/-8.4(L) versus - 1.2+/-6.0(J), p <0.05), and systolic BP at 30 minutes was increased in the J group(deltaBP: +4.0+/-9.0 mmHg(L) versus +10.1+/-9.9 mmHg(J), p <0.05). 3 patients in the J, and 2 in the L group had complaint of headache and/or upper arm discomfort.
CONCLUSION
HR was increased in the lithotomy position, systolic BP at 30 minutes after position change was increased in the J group. But the differences were not so significant clinically. Another parameters were no differences between the two groups. Therefore there is no supiriority in lithotomy or jack-knife position on HR, BP and ABG when anorectal procedure is undergone under spinal anesthesia.