Withholding Some HT Meds May Cut Periop Hypotension

MIAMI BEACH — Patients taking most antihypertensive medications the morning of surgery are not at higher risk for hypotension or more vasopressor use during the perioperative period, according to a retrospective study.

However, significantly more patients taking an angiotensin-converting enzyme inhibitor experienced these events, and there was a higher incidence among those taking an angiotensin-receptor blocker as well.

“We think they should withhold ACE inhibitors and angiotensin-receptor blockers [ARBs]” on the morning of surgery, Dr. Matthieu Touchette said in an interview.

Dr. Touchette and his colleagues compared 371 patients with a diagnosis of hypertension evaluated in the preoperative clinic within the department of medicine at the University of Sherbrooke Central Hospital in Quebec.

All patients had elective surgery and a hospital length of stay longer than 1 day between November 2005 and November 2006. The researchers compared 91 patients who did not take their antihypertensive medication on the morning of surgery with 280 patients who did.

Their aim was to compare hypotensive episodes and use of vasopressors during the perioperative period between these groups. Results were presented in a poster at a meeting on perioperative medicine sponsored by the University of Miami.

Although the guidelines from the American College of Cardiology and the American Heart Association on antihypertensive medications suggest withholding ACE inhibitors and ARBs on the morning of surgery (Circulation 2007;116:e418-99), “we wanted to check if all hypertensive medications make a difference—do they really change” the perioperative course? said Dr. Touchette, an internist at the University of Sherbrooke Central Hospital.

The mean age of the patients was 67 years in the medicine group (43% men) and 69 years in the no-medicine group (54% men). There was more hypertension during preoperative evaluation in the medicine group (91%) than in the no-medicine group (81%). A lower proportion of patients in the medicine group had cardiovascular disease (24% vs. 46%), dyslipidemia (51% vs. 71%), and atrial fibrillation/flutter (7% vs. 21%).

The type of medication that patients were taking at the time of the preoperative clinical evaluation, not surprisingly, corresponded with these diagnoses. For example, more patients in the medicine group were taking diuretics (56% vs. 43%). In contrast, a higher proportion of patients who did not take hypertensives before surgery were on beta-blockers (54% vs. 23%), calcium channel blockers (48% vs. 25%), and nitroglycerin (9% vs. 2%).

“We found, and it's very interesting, that whether we give pills or not, many people have hypotension during surgery,” Dr. Touchette said.

Hypotension, defined as systolic blood pressure less than 90 mm Hg, occurred in 58% of the medicine group and 46% of the no-medicine group. “We were surprised how many of our patients have hypotensive episodes during surgery. I am an internist—so I am not usually in the OR.”

Despite a high incidence of perioperative hypotension, Dr. Touchette and his colleagues found no significant difference between groups. “There was no overall difference if we look at all the medications as one big bag,” he said.

They also found no significant difference in perioperative use of vasopressors between those who took their antihypertensive the morning of surgery (71%) and those who did not (79%).

However, “when we looked at individual drugs, the ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period,” Dr. Touchette said. Among the patients taking medication on the morning of surgery, there was a statistically significant increased association between perioperative hypotension or vasopressor use if they took an ACE inhibitor (adjusted odds ratio, 2.36), compared with those who did not take this type of medication.

Similarly, patients taking an ARB just before surgery had an increased risk for these two factors, although it was not statistically different (adjusted OR, 2.38).

In contrast, there was a lower risk among patients taking a calcium channel blocker on the morning of surgery (adjusted OR, 0.73), a diuretic (OR, 0.83), or a beta-blocker (OR, 0.89).

Dr. Touchette said that in the future they “would like to try to reproduce the study in a prospective manner.”

'ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period.' DR. TOUCHETTE

MIAMI BEACH — Patients taking most antihypertensive medications the morning of surgery are not at higher risk for hypotension or more vasopressor use during the perioperative period, according to a retrospective study.

However, significantly more patients taking an angiotensin-converting enzyme inhibitor experienced these events, and there was a higher incidence among those taking an angiotensin-receptor blocker as well.

“We think they should withhold ACE inhibitors and angiotensin-receptor blockers [ARBs]” on the morning of surgery, Dr. Matthieu Touchette said in an interview.

Dr. Touchette and his colleagues compared 371 patients with a diagnosis of hypertension evaluated in the preoperative clinic within the department of medicine at the University of Sherbrooke Central Hospital in Quebec.

All patients had elective surgery and a hospital length of stay longer than 1 day between November 2005 and November 2006. The researchers compared 91 patients who did not take their antihypertensive medication on the morning of surgery with 280 patients who did.

Their aim was to compare hypotensive episodes and use of vasopressors during the perioperative period between these groups. Results were presented in a poster at a meeting on perioperative medicine sponsored by the University of Miami.

Although the guidelines from the American College of Cardiology and the American Heart Association on antihypertensive medications suggest withholding ACE inhibitors and ARBs on the morning of surgery (Circulation 2007;116:e418-99), “we wanted to check if all hypertensive medications make a difference—do they really change” the perioperative course? said Dr. Touchette, an internist at the University of Sherbrooke Central Hospital.

The mean age of the patients was 67 years in the medicine group (43% men) and 69 years in the no-medicine group (54% men). There was more hypertension during preoperative evaluation in the medicine group (91%) than in the no-medicine group (81%). A lower proportion of patients in the medicine group had cardiovascular disease (24% vs. 46%), dyslipidemia (51% vs. 71%), and atrial fibrillation/flutter (7% vs. 21%).

The type of medication that patients were taking at the time of the preoperative clinical evaluation, not surprisingly, corresponded with these diagnoses. For example, more patients in the medicine group were taking diuretics (56% vs. 43%). In contrast, a higher proportion of patients who did not take hypertensives before surgery were on beta-blockers (54% vs. 23%), calcium channel blockers (48% vs. 25%), and nitroglycerin (9% vs. 2%).

“We found, and it's very interesting, that whether we give pills or not, many people have hypotension during surgery,” Dr. Touchette said.

Hypotension, defined as systolic blood pressure less than 90 mm Hg, occurred in 58% of the medicine group and 46% of the no-medicine group. “We were surprised how many of our patients have hypotensive episodes during surgery. I am an internist—so I am not usually in the OR.”

Despite a high incidence of perioperative hypotension, Dr. Touchette and his colleagues found no significant difference between groups. “There was no overall difference if we look at all the medications as one big bag,” he said.

They also found no significant difference in perioperative use of vasopressors between those who took their antihypertensive the morning of surgery (71%) and those who did not (79%).

However, “when we looked at individual drugs, the ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period,” Dr. Touchette said. Among the patients taking medication on the morning of surgery, there was a statistically significant increased association between perioperative hypotension or vasopressor use if they took an ACE inhibitor (adjusted odds ratio, 2.36), compared with those who did not take this type of medication.

Similarly, patients taking an ARB just before surgery had an increased risk for these two factors, although it was not statistically different (adjusted OR, 2.38).

In contrast, there was a lower risk among patients taking a calcium channel blocker on the morning of surgery (adjusted OR, 0.73), a diuretic (OR, 0.83), or a beta-blocker (OR, 0.89).

Dr. Touchette said that in the future they “would like to try to reproduce the study in a prospective manner.”

'ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period.' DR. TOUCHETTE

MIAMI BEACH — Patients taking most antihypertensive medications the morning of surgery are not at higher risk for hypotension or more vasopressor use during the perioperative period, according to a retrospective study.

However, significantly more patients taking an angiotensin-converting enzyme inhibitor experienced these events, and there was a higher incidence among those taking an angiotensin-receptor blocker as well.

“We think they should withhold ACE inhibitors and angiotensin-receptor blockers [ARBs]” on the morning of surgery, Dr. Matthieu Touchette said in an interview.

Dr. Touchette and his colleagues compared 371 patients with a diagnosis of hypertension evaluated in the preoperative clinic within the department of medicine at the University of Sherbrooke Central Hospital in Quebec.

All patients had elective surgery and a hospital length of stay longer than 1 day between November 2005 and November 2006. The researchers compared 91 patients who did not take their antihypertensive medication on the morning of surgery with 280 patients who did.

Their aim was to compare hypotensive episodes and use of vasopressors during the perioperative period between these groups. Results were presented in a poster at a meeting on perioperative medicine sponsored by the University of Miami.

Although the guidelines from the American College of Cardiology and the American Heart Association on antihypertensive medications suggest withholding ACE inhibitors and ARBs on the morning of surgery (Circulation 2007;116:e418-99), “we wanted to check if all hypertensive medications make a difference—do they really change” the perioperative course? said Dr. Touchette, an internist at the University of Sherbrooke Central Hospital.

The mean age of the patients was 67 years in the medicine group (43% men) and 69 years in the no-medicine group (54% men). There was more hypertension during preoperative evaluation in the medicine group (91%) than in the no-medicine group (81%). A lower proportion of patients in the medicine group had cardiovascular disease (24% vs. 46%), dyslipidemia (51% vs. 71%), and atrial fibrillation/flutter (7% vs. 21%).

The type of medication that patients were taking at the time of the preoperative clinical evaluation, not surprisingly, corresponded with these diagnoses. For example, more patients in the medicine group were taking diuretics (56% vs. 43%). In contrast, a higher proportion of patients who did not take hypertensives before surgery were on beta-blockers (54% vs. 23%), calcium channel blockers (48% vs. 25%), and nitroglycerin (9% vs. 2%).

“We found, and it's very interesting, that whether we give pills or not, many people have hypotension during surgery,” Dr. Touchette said.

Hypotension, defined as systolic blood pressure less than 90 mm Hg, occurred in 58% of the medicine group and 46% of the no-medicine group. “We were surprised how many of our patients have hypotensive episodes during surgery. I am an internist—so I am not usually in the OR.”

Despite a high incidence of perioperative hypotension, Dr. Touchette and his colleagues found no significant difference between groups. “There was no overall difference if we look at all the medications as one big bag,” he said.

They also found no significant difference in perioperative use of vasopressors between those who took their antihypertensive the morning of surgery (71%) and those who did not (79%).

However, “when we looked at individual drugs, the ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period,” Dr. Touchette said. Among the patients taking medication on the morning of surgery, there was a statistically significant increased association between perioperative hypotension or vasopressor use if they took an ACE inhibitor (adjusted odds ratio, 2.36), compared with those who did not take this type of medication.

Similarly, patients taking an ARB just before surgery had an increased risk for these two factors, although it was not statistically different (adjusted OR, 2.38).

In contrast, there was a lower risk among patients taking a calcium channel blocker on the morning of surgery (adjusted OR, 0.73), a diuretic (OR, 0.83), or a beta-blocker (OR, 0.89).

Dr. Touchette said that in the future they “would like to try to reproduce the study in a prospective manner.”

'ACE inhibitors and ARBs were associated with more hypotensive episodes in the perioperative period.' DR. TOUCHETTE