Refractory Hypotension During General Anesthesia Despite Withholding Telmisartan

Angiotensin receptor blockers (ARBs) are commonly used to treat hypertension. However, similar to angiotensin-converting enzyme inhibitors, ARBs can also cause refractory hypotension during general anesthesia. Therefore, it has been recommended that ARBs be withheld for 24 hours prior to the induction of anesthesia. This is a case report of refractory hypotension requiring the administration of potent vasopressors after the induction of general anesthesia despite withholding telmisartan for 24 hours. In the same patient undergoing a subsequent general anesthetic, telmisartan was withheld for 5 days before induction, leading to mild intraoperative hypotension that responded adequately to phenylephrine. The primary cause of refractory hypotension during the first general anesthetic was suspected to be an insufficient telmisartan washout period. Telmisartan's half-life of 24 hours is notably the longest of all ARBs in current use. This case report demonstrates that refractory hypotension during general anesthesia cannot always be avoided by withholding telmisartan for 24 hours before the induction of anesthesia. Therefore, a washout period greater than 24 hours is preferable for patients taking telmisartan.