Pre-anesthesia systolic blood pressure increases with age regardless of sex.

PURPOSE

Pre-anesthesia hypertension (PAH) is the temporary elevation of blood pressure (BP), compared with normal ambulatory recorded BP or self-measured BP at home, in patients waiting for operation in the operating room (OR) before anesthesia induction. In general, the incidence of sustained hypertension (SH) increases progressively with age and the increase is greater in males than in females. In this study, we investigated the influence of age and sex on PAH.

METHODS

Sampling data on consecutive patients who were more than 20 years old and who had undergone surgery under general, intrathecal, or epidural anesthesia were retrospectively collected from hospital records and anesthesia records. Patients with SH, which was defined as a past history of hypertension and taking oral antihypertensive medications, were excluded from the analyses, and the data of 231 patients, 102 males and 129 females, were used for the analyses.

RESULTS

The proportions of male and female patients with a systolic BP (sBP) of more than 140 mmHg in the OR before anesthesia induction were 55.9 and 42.6%, respectively. The proportions of male and female patients with a diastolic BP (dBP) of more than 90 mmHg were 34.3 and 23.3%, respectively. There was no difference in the proportions of male and female patients with PAH. The differences in sBP between measurements in the hospital room (HR) before the operation and those in the OR (ΔsBP) in males and females were 22.9 ± 25.6 and 19.0 ± 24.0 mmHg, respectively. The differences in dBP between measurements in the HR and those in the OR (ΔdBP) in males and females were 12.7 ± 16.5 and 8.4 ± 17.9 mmHg, respectively. There were no differences in ΔsBP and ΔdBP between males and females. The sBP in the OR and the ΔsBP increased significantly with age in both males and females.

CONCLUSION

Age is an important clinical factor related to PAH. Pre-anesthesia sBP and the change in pre-anesthesia sBP increase progressively with age regardless of sex. These findings suggest that the higher BP seen in the elderly in the OR before anesthesia induction, as reported previously, might be explained in part by a greater impact of PAH in older people.