Procedure-specific Risk Factors

In medicine, a stepwise approach to the assessment of cardiac risk (combined incidence of nonfatal myocardial infarction, heart failure, and sudden cardiac death) in association with noncardiac procedures is both efficacious and cost-effective.30 Various noncardiac medical surgical procedures have been stratified and tend to fall into three categories: high risk (>5%), intermediate risk (<5%), and low risk (<1%). Clearly, different procedures are associated with different cardiac risks and these differences predictably reflect such procedure-specific variables as fluid shifts, blood loss, duration of a procedure, and associated psychological and physiological (i.e., general anesthesia-associated) stress levels.

There are no adequately controlled or randomized clinical trials that help define dental procedure-related hypertensive or other cardiovascular risks. However, according to a retrospective study in Seattle and King Counties, Washington, with a combined population 1.5 million based on the 1990 census, over a period of seven years (1990-1996), only six cardiac events were documented in 9707 community-based dental practices at an annual rate of <0.002 per dental practice (note: per dental practice not per dentist).31 Based on this evidence, it can be concluded that dental procedures, in general, are low- or very low-cardiac risk procedures.

Several other investigators found no significant BP increase during dental treatment.32-36 In one study comparing the blood pressure during dental examination and dental treatment, a mean difference of 8 mmHg in SBP and 1 mmHg in DBP was noted with the most traumatic procedure (oral surgery).37 Mean changes related to restorative dentistry were 4 mmHg in SBP and 3 mmHg in DBP. Another report concluded that while the actual administration of a local anesthetic agent may produce a transient increase in BP, the BP decreases after the needle is removed from the mouth.38

Finally, a systematic review of the literature concluded that, although adverse events may occur in uncontrolled hypertensive patients, the use of epinephrine in local anesthetic agents has minimal effect on BP.39 However, the BP should be monitored closely if general anesthesia is being administered to hypertensive individuals because of potential wide fluctuations in BP and the risk of hypotension in those receiving antihypertensive drugs.12