How should antihypertensive medications be managed in patients with hypertension undergoing surgery?

From the Guidelines

Antihypertensive medications should generally be continued through the perioperative period, with most medications taken on the morning of surgery with a small sip of water. The management of antihypertensive medications in patients undergoing surgery is crucial to prevent perioperative complications. According to the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1, the following recommendations are made:

• Beta-blockers should be continued in patients who have been on them chronically 1.
• ACE inhibitors or ARBs may be discontinued perioperatively, but this decision should be made on a case-by-case basis 1.
• Patients with severe hypertension (SBP ≥ 180 mmHg or DBP ≥ 110 mmHg) may need to have their surgery deferred 1.
• Abrupt discontinuation of beta-blockers or clonidine is potentially harmful and should be avoided 1.
• Beta-blockers should not be started on the day of surgery in beta-blocker-naive patients 1.

Some key points to consider when managing antihypertensive medications in the perioperative period include:

• Monitoring blood pressure closely during surgery and postoperatively
• Resuming oral medications as soon as possible after surgery
• Using IV alternatives temporarily if needed
• Assessing other potential contributing factors to perioperative hypertension, such as volume status, pain control, oxygenation, and bladder distention.

It's also important to note that the 2019 KDOQI US commentary on the 2017 ACC/AHA hypertension guideline 1 provides similar recommendations, emphasizing the importance of continuing beta-blockers and considering the discontinuation of ACE inhibitors or ARBs perioperatively. Overall, the goal is to balance the risks of perioperative hypertension against potential medication-related complications during surgery, and to prioritize the patient's safety and well-being.

From the FDA Drug Label

Administration of clonidine hydrochloride tablets, USP should be continued to within four hours of surgery and resumed as soon as possible thereafter. Blood pressure should be carefully monitored during surgery and additional measures to control blood pressure should be available if required

• Preoperative assessment for patients with hypertension undergoing surgery should include careful monitoring of blood pressure.
• Antihypertensive medications, such as clonidine, should be continued until four hours before surgery and resumed as soon as possible after surgery.
• Blood pressure monitoring is crucial during surgery, and additional measures to control blood pressure should be available if needed 2.

From the Research

Preoperative Assessment for Hypertension Patients

• The management of antihypertensive medications in patients with hypertension undergoing surgery is crucial to ensure patient safety 3.
• Current evidence supports the perioperative continuation of β-blockers, calcium-channel blockers, and α-2 agonists 3.
• Diuretics should be discontinued on the day of the surgery and resumed in the postoperative period 3.
• The decision to continue or stop antihypertensive medications should be based on the individual patient's risk factors and medical history 3, 4.

Perioperative Management of Antihypertensive Medications

• Preoperative antihypertensive medications should be continued up till the procedure, unless the blood pressure is more than 180 mm Hg systolic or 110 mm Hg diastolic 4.
• Postoperative hypertension may require intravenous medications, and oral nifedipine should generally be avoided due to the risk of inducing an uncontrolled hypotensive response and cardiac ischemia 4.
• The administration of combined oral antihypertensive medications on the day of surgery may increase the risk of postoperative acute kidney injury (AKI) 5.

Risk Stratification and Perioperative Hemodynamic Management

• Total cardiovascular risk rather than blood pressure alone should determine the preoperative strategy for hypertensive patients 6.
• Target organ damage associated with hypertensive disease rather than high blood pressure per se appears to determine perioperative risk 6.
• An individualized and pathophysiology-based approach to control blood pressure may be the best option to guide patients through the perioperative period 6.

As-Needed Antihypertensive Therapy in Surgical Patients

• The practice of using as-needed antihypertensive therapy in surgical patients is common, but its cost and benefit are not well established 7.
• Further research is warranted to determine the prevalence of this practice in other centers or national regions, as well as its cost and benefit 7.