Anaesthesia in special conditions: surgery in hypertensive patients

Overview

Perioperative hypertension should be recognized promptly and managed systematically. Ensure accurate blood pressure measurement, identify reversible causes, and treat persistent hypertension appropriately.

Assessment

Monitor

Continuously monitor:

• Blood pressure

• Heart rate

• ECG rhythm

• End-tidal carbon dioxide (EtCO₂)

• Temperature

If the patient is adequately oxygenated and ventilated, consider deepening the anaesthetic.

Examine the patient

Assess for signs that may indicate the underlying cause of hypertension:

• Pupillary changes (raised intracranial pressure)

• Diaphoresis or flushing (carcinoid syndrome, pheochromocytoma, hyperthyroidism)

• Muscle rigidity (malignant hyperthermia, serotonin syndrome)

• Bladder distension

• Hyperthermia (thyroid storm, malignant hyperthermia, serotonin syndrome)

Check drugs and equipment

Evaluate for possible technical or medication-related causes:

• Medication errors

• Total intravenous anaesthesia (TIVA) failure or breathing circuit disconnection, which may result in awareness

• Tourniquet pain

• Equipment malfunction causing falsely elevated blood pressure readings

Pharmacological management

If hypertension persists after correcting reversible causes, administer one of the following:

• Hydralazine (IV): 5–20 mg by slow IV push every 20 minutes (maximum total dose 30 mg).

OR

• Labetalol (IV): 5–20 mg every 10 minutes (maximum total dose 300 mg).

OR

• Esmolol (IV): 0.5 mg/kg over 1 minute, followed by an infusion starting at 50 micrograms/kg/minute.

OR

• Nitroglycerin (IV): Initial bolus of 50–100 micrograms, followed by an infusion starting at 10 micrograms/minute.

Additional management

• Identify and treat the underlying cause of hypertension, such as inadequate analgesia or pain.