Use of Dexmedetomidine in a Patient Allergic to Clonidine Presenting for an Awake Craniotomy: A Case Report

Introduction: The use of dexmedetomidine with concurrent scalp block is increasingly being utilized as an effective and safe anesthetic approach for awake craniotomy (AC). Dexmedetomidine is an alpha-2 adrenergic receptor (α2-AR) agonist with dose-dependent sedative, analgesic, and anxiolytic properties while preserving respiratory function. The challenge with the use of dexmedetomidine arises when the patient in question has a clonidine allergy that is also an α2-AR agonist. Currently there aren’t any published literature regarding the use of dexmedetomidine in a patient allergic to clonidine. Case Presentation: A 48-year-old male with chronic obstructive pulmonary disease, obstructive sleep apnea, and body mass index of 54 with clonidine allergy presents for an AC. Given the goals of the surgery and patient comorbidities, we planned for monitored anesthesia care with intravenous (IV) dexmedetomidine, remifentanil, and propofol. We discussed the use of dexmedetomidine with the patient and the potential risk of allergic reaction given his allergy to clonidine. Patient understood the risk and consented to the anesthetic plan. AC was successfully performed with IV dexmedetomidine, remifentanil, and propofol.Conclusion: Although both dexmedetomidine and clonidine have some functional similarities in terms of acting on the central and peripheral nervous system, there are marked differences between the two based on chemical structure, receptor affinity, and metabolism of the drug. This case highlights the successful use of dexmedetomidine in a patient with known allergy of rash to clonidine.

Recommendations for anesthetic management for intraoperative neuromodulation cases

This paper performs a review of current literature as well as uses our single-center experience to discuss pre-operative, intra-operative and, briefly, postoperative management for dorsal column stimulators (DCSs), dorsal root ganglion (DRG) stimulators, peripheral nerve stimulators (PNSs) and intrathecal pumps. Generally, pre-operative antibiotics are recommended with discontinuation within 24 h postoperatively. For dorsal column and DRG stimulation, monitored anesthesia care or general anesthesia with intra-operative neuromonitoring is recommended; for peripheral nerve stimulation and intrathecal pump implementation, monitored anesthesia care is preferred. There is little information on appropriate anesthetic management during these forms of neuromodulation. More research is necessary to articulate specific pre-operative, intra-operative and postoperative management guidelines and recommendations for dorsal column stimulator, DRG stimulation, PNS and intrathecal pump implantation.

Postoperative Pulmonary Complications after Transcatheter Aortic Valve Implantation under Monitored Anesthesia Care versus General Anesthesia: Retrospective Analysis at a Single Large Volume Center

Few studies to date have assessed the postoperative pulmonary complications after transcatheter aortic valve implantation (TAVI) according to the anesthesia method. The present study aims to compare the effects of general anesthesia (GA) or monitored anesthesia care (MAC) on postoperative outcomes in patients undergoing TAVI. This retrospective cohort study included 578 patients who underwent TAVI through the trans-femoral approach between August 2011 and May 2019 at a single tertiary academic center. The primary outcome was postoperative pulmonary complications, which were defined as the occurrence of one or more pulmonary complications, such as respiratory failure, respiratory infection, and radiologic findings, within 7 days after TAVI. Secondary outcomes included postoperative delirium, all-cause 30-day mortality rate, 30-day readmission rate, reoperation rate, vascular complications, permanent pacemaker/implantable cardioverter-defibrillator insertion, length of stay in the ICU, hospital stay, and incidence of stroke. Of the 589 patients, 171 underwent TAVI under general anesthesia (GA), and 418 under monitored anesthesia care (MAC). The incidence of postoperative pulmonary complications was significantly higher in the GA than in the MAC group (17.0% vs. 5.3%, p < 0.001). Anesthetic method significantly affected the occurrence of postoperative pulmonary complications, but not of delirium. ICU stay was significantly shorter in the MAC group, as were operation time, the volume of fluid administered during surgery, heparin dose, transfusion, and inotrope requirements. TAVI under MAC can increase the efficiency of medical resources, reducing the lengths of ICU stay and the occurrence of postoperative pulmonary complications, compared with TAVI under GA.

Awake craniotomy using a high-flow nasal cannula with oxygen reserve index monitoring - A report of two cases -

Background: Awake craniotomy is a well-tolerated procedure for the resection of brain tumors residing within or close to the eloquent cortical areas. Monitored anesthesia care (MAC) is a dominant anesthetic approach for awake craniotomy; however, it is associated with inherent challenges such as desaturation and hypercapnia, which may lead to various complications. The prevention of respiratory insufficiency is important for successful awake craniotomy. As measures to avoid respiratory depression, the use of high-flow nasal cannula (HFNC) can improve patient oxygenation and monitor the oxygen reserve index (ORi) to detect hypoxia earlier. Case: We report two cases of awake craniotomy with MAC using HFNC and ORi. We adjusted the fraction of inspired oxygen of the HFNC according to the ORi level. The patient underwent successful awake craniotomy without a desaturation event or additional airway intervention. Conclusions: Combined HFNC and ORi monitoring may provide adequate oxygen reserves in patients undergoing awake craniotomy.