In 44 (8.5%) of the 516 implant surgery cases, oral nifedipine had to be administered, since preoperative SBP was higher than 160 mmHg in these patients. Within 30 min of administration of nifedipine, SBP of hypertensive patients decreased to a similar range as that of hypertensive patients who did not need administration of oral nifedipine. Intravenous sedation after nifedipine administration to hypertensive patients resulted in stable hemodynamics during implant surgery.

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure [6] classified hypertensive patients into five categories based on systolic or diastolic blood pressure. Patients with normal blood pressure (<120/80 mmHg), prehypertension (120 to 139/80 to 89 mmHg), or stage I hypertension (140 to 159/90 to 99 mmHg) can receive regular dental care, though a stress reduction protocol is necessary for stage I hypertension [2,7]. In accordance with the guidelines during oral surgery, the blood pressure of hypertensive patients should be maintained at a normal or prehypertension level. RPP is a reliable predictor of myocardial oxygen consumption [8], and RPP >12,000 bpm × mmHg is associated with myocardial ischemia [9,10]. In this study, although blood pressure was managed by a physician, hypertensive patients showed SBP >160 mmHg when they visited the dental office for dental implant surgery, and 50% of hypertensive patients showed high RPP after 30 min of rest. In patients presenting with high blood pressure and high RPP, anxiety and fear must be reduced by conscious sedation and antihypertensives to prevent cardiovascular complications during dental implant surgery.

Increases in SBP due to psychological stress are proportional to age and baseline blood pressure [4]. Intravenous sedation stabilizes measurable changes in blood pressure and pulse rate due to fear and anxiety about dental treatment and has been used to manage patients with ischemic heart disease and hypertension [11]. In this study, the effect of intravenous sedation was as follows: SBP and RPP, compared with those prior to intravenous sedation, were decreased by 15% and 20% in patients with normal blood pressure, 15% and 25% in hypertensive patients without oral nifedipine, and 15% to 20% and 20% to 30% in hypertensive patients with administered nifedipine, respectively. That is, SBP and myocardial oxygen consumption of prehypertension and stage I hypertension can be reduced to the levels recommended for dental treatment before surgery by intravenous sedation.