When hypertensive patients undergo oral surgery

The pharmaceutical management of hypertensive patients during oral surgery requires controlling patient stress and anxiety and knowing the uses and adverse interactions of antihypertensive drugs, according to recently released guidelines by the American Association of Oral and Maxillofacial Surgeons (AAOMS).

It is, in fact, important that pharmacists be aware of the medical implications of hypertension, especially as acute postoperative hypertension (APH) is a common occurrence after any surgery, said Curtis Haas, Pharm.D., assistant professor of pharmacy practice at the University at Buffalo.

"The potential for APH has important implications for care provided on the postanesthesia unit, the intensive care unit, and the surgical floor for 24 to 48 hours, and sometimes longer," said Haas. Familiarity with the medical and pharmaceutical implications of APH is an important element of quality pharmaceutical care at the health-system level, he added.

"When treatment of APH is necessary, therapy should be individualized for the patient," said Haas. Although no single treatment agent is preferred, effective options include sodium nitroprusside, nitroglycerin, labetalol, and nicardipine, he said.

Given the prevalence of hypertension, individualized treatment has significant pharmaceutical implications for oral and maxillofacial surgeons in the office setting as well, said Cunningham. The condition affects 20% to 30% of the adult population, and becomes more prevalent among older patients. And the risk of hypertension doubles for African-Americans.

A particularly dangerous element of treating hypertensive patients in oral and maxillofacial surgical settings is that the condition is undertreated: "Despite the prevalence of hypertension and its associated complications, only 29% of patients with hypertension are treated, and only 45% of those treated with antihypertensive medications have controlled disease," according to the AAOMS guidelines.

The guidelines are spelled out in an article titled "Hypertension: Classification, Pathophysiology, and Management During Outpatient Sedation and Local Anesthesia," published in the January 2006 issue of the AAOMS Journal of Oral and Maxillofacial Surgery. In developing the guidelines, Cunningham and his colleagues reviewed a new classification system for the treatment of hypertensive patients undergoing oral surgery. They also reviewed treatment recommendations for hypertensive patients undergoing sedation or anesthesia.

The revised classification system is based on the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7), which also assimilates findings from new hypertension studies and clinical trials, and includes clearer, more concise guidelines for clinicians. Hypertension is defined in the guidelines as "a systolic blood pressure (SBP) higher than 140 mmHg or a diastolic blood pressure (DBP) higher than 90 mmHg. Diagnosis is based on the average of two or more readings taken at each of two or more visits after an initial screening."

The JNC 7 guidelines classify hypertension into three groups within that definition, each with pharmaceutical implications. According to Cunningham, the new classification system for hypertension and its associated cardiovascular risk factors "is more helpful to oral and maxillofacial surgeons than previous such documents.... Knowledge of the clinical classification of hypertensive stages and possible drug interactions within each class is essential for determining proper treatment."