Remimazolam sedation during breast surgery under exclusive locoregional anesthesia in a super-obese patient

Sir, Remimazolam is a novel ultra–short-acting benzodiazepine characterized by rapid onset and offset of action. As an ester-based compound, it is hydrolyzed by tissue esterases to an inactive metabolite, making its clearance largely independent of hepatic, and renal function.[1] These pharmacokinetic properties render remimazolam attractive for procedural sedation in high-risk patients. We report the case of a 59-year-old super-obese woman (body mass index 51 kg/m²) scheduled for quadrantectomy with sentinel lymph node dissection. Her medical history included arterial hypertension, atrial myxoma with moderate-to-severe mitral regurgitation, and reduced left ventricular ejection fraction. Airway assessment suggested potential difficulty (Mallampati class III, neck circumference 50 cm). Given the relevant cardiopulmonary comorbidities and anticipated airway challenges, a pure locoregional anesthetic strategy was chosen. Ultrasound-guided serratus anterior plane and parasternal blocks were performed using a 100-mm insulated needle (Ultraplex 360, B. Braun). At the mid-axillary line, 25 ml of local anesthetic was injected either superficial or deep to the serratus anterior muscle at the level of the fourth rib. An additional 10 ml was injected between the pectoralis major and intercostal muscles near the parasternal line at the level of the fifth costal cartilage. The anesthetic mixture consisted of levobupivacaine 0.5% (10 ml), lidocaine 1% (10 ml), dexmedetomidine 40 μg, and saline solution (15 ml), for a total volume of 35 ml. Light sedation was initiated with remimazolam (induction dose 0.2–0.4 mg/kg; maintenance dose 0.3–0.5 mg/kg/h), titrated to maintain electroencephalographic entropy values between 60 and 70. The procedure was completed uneventfully. Postoperative analgesia consisted of acetaminophen 1 g three times daily. Pain intensity remained low throughout the postoperative period (numerical rating scale 0/10 at rest and 2/10 on movement). The patient was discharged home on the day of surgery. Written informed consent for publication was obtained from the patient. Remimazolam appears particularly well-suited for obese patients due to its minimal cumulative effect, predictable context-sensitive half-time, and limited cardiovascular depression.[1,2] In obese patients undergoing gastrointestinal endoscopy, remimazolam-based anesthesia has been associated with a reduced incidence of hypoxemia and fewer respiratory complications compared with propofol, as well as higher patient satisfaction.[2,3] Case reports have further described its successful use in morbidly obese and super-super obese patients undergoing general anesthesia or complex procedures, highlighting stable hemodynamics and acceptable respiratory safety.[4] In addition, remimazolam has demonstrated superior hemodynamic stability compared with propofol in hypertensive patients, with fewer episodes of hypotension and reduced vasopressor requirements, without prolonging recovery.[5] This profile is particularly relevant in super-obese patients, who present with cardiovascular comorbidities and an increased risk of perioperative hemodynamic instability. To our knowledge, this is the first report describing the use of remimazolam for procedural sedation in a super-obese, hypertensive patient undergoing breast surgery performed exclusively under locoregional anesthesia. In this setting, remimazolam allowed the procedure to be comfortably using regional anesthesia alone, with preserved respiratory stability and rapid postoperative recovery. Although further data are needed, this case supports the potential role of remimazolam as a valuable sedative option in high-risk obese patients. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understand that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.