Remimazolam-based anesthesia in a patient with hypertrophic obstructive cardiomyopathy undergoing radical colorectal cancer surgery: A case report

Background: The goal of anesthesia in patients with hypertrophic obstructive cardiomyopathy (HOCM) is to reduce the risk of left ventricular outflow tract obstruction triggered by anesthetics. Remimazolam is a newly developed anesthetic that has been reported to have superior hemodynamic stability. There have been no reports on the completion of non-cardiac surgery with remimazolam in patients with HOCM. Methods: Here we report the case of a 49-year-old man diagnosed with hypertrophic obstructive cardiomyopathy who underwent resection of colon cancer with remimazolam and remifentanil anesthesia. A bolus 0.3 mg/kg remimazolam was administered for anesthesia induction, and then adjusted to 2 mg/kg/h to maintain anesthesia. Set the pain threshold index to 50 to auto-control the infusion speed of remifentanil. Results: No hypotension occurred during anesthesia, and norepinephrine was not administered. After conversion to open surgery, the patient’s blood pressure elevated and reduced with urapidil and esmolol. Conclusion: In this patient with HOCM, remimazolam and remifentanil provided adequate anesthesia for induction and maintenance to complete the right hemicolectomy.