Replacement of dexmedetomidine loading with midazolam for sedation in elderly patients with spinal anesthesia

Beneficial effects of the remifentanil/thiopental combination on cardiac function and redox status in diabetic rats

This study aimed to examine the effect of thiopental monotherapy as well as its combination with different agents used in anesthesia induction, on cardiac function and redox state of rats with type 1 diabetes mellitus (T1DM). A total of 40 Wistar albino male rats were used in this study and randomly divided into five groups: thiopental (TIO), fentanyl + thiopental (FEN + TIO), remifentanil + thiopental (REM + TIO), midazolam + thiopental (MID + TIO), and dexmedetomidine + thiopental (DEX + TIO). Animals were anesthetized by intraperitoneal injection of thiopental 85 mg/kg, fentanyl 0.005 mg/kg, remifentanil 0.04 mg/kg, midazolam 2.5 mg/kg, and dexmedetomidine 0.05 mg/kg of body weight. Four weeks after T1DM induction, all animals were subjected to a short narcosis of tested anesthetic, sacrificed by cervical dislocation and the hearts were retrogradely perfused according to Langendorff technique. Our research demonstrated that most combined anesthetics negatively influenced cardiodynamic parameters and redox state in diabetic rats. However, significantly improved cardiac contractility associated with enhanced antioxidative capacity was achieved in the combination of TIO with REM, which distinguishes this anesthetic combination as the therapy with the most pronounced positive effect on cardiac function in state of T1DM.

Risk factors for dexmedetomidine-associated bradycardia during spinal anesthesia: A retrospective study

Sedation with dexmedetomidine is needed for patients undergoing spinal anesthesia. However, dexmedetomidine sedation increases the incidence of bradycardia. We aimed to identify and to evaluate risk factors for bradycardia in patients undergoing spinal anesthesia with dexmedetomidine sedation. The records of 91 patients who underwent spinal anesthesia with sedation using dexmedetomidine were reviewed retrospectively. For this study, we identified 15 characteristics of included patients from this group who underwent lower leg surgery and had an estimated blood loss of <300 mL. We collected details on potential risk factors for bradycardia from their clinical records. These factors included age, American Society of Anesthesiologists classification, height, weight, sensory level of spinal anesthesia, history of hypertension, diabetes mellitus, loading, and maintenance dose of dexmedetomidine, tourniquet time, initial diastolic and systolic blood pressure, initial heart rate (HR), and anesthesia and surgery duration. The primary endpoint of this study was the occurrence of bradycardia. We identified potential risk factors using logistic regression analysis. The incidence of bradycardia was obtained in 23 (25%) of 91 patients. Initial HR and tourniquet time were significant individual predictive factors for the occurrence of bradycardia. Logistic regression analysis showed that adjusted baseline HR and duration of tourniquet use were risk factors for bradycardia. Patients should be monitored when undergoing spinal anesthesia with sedation using dexmedetomidine for bradycardia when they have a long tourniquet time. A low initial HR could also be a predictive factor for bradycardia.

Intraoperative Dexmedetomidine Versus Midazolam in Patients Undergoing Peripheral Surgery With Mild Traumatic Brain Injuries: A Retrospective Cohort Analysis

Background:

The intra- and postoperative effects of dexmedetomidine are not completely consistent and midazolam/fentanyl is most widely used in peripheral surgeries. The objectives of the study were to evaluate the sedative, analgesic, hemodynamic, anti-inflammatory, and antioxidant effects of dexmedetomidine against midazolam in patients undergoing peripheral surgeries with mild traumatic brain injuries.

Methods:

Medical records of patients who underwent peripheral surgeries with mild traumatic brain injury were included in the analysis. Patients received intraoperative midazolam (MDZ cohort, n = 225) or dexmedetomidine (DEX cohort, n = 231). Pre-, intra-, and postoperative characteristics of patients were collected and analyzed.

Results:

After administration of anesthesia, up to 40 minutes, patients of the MDZ group had lower modified observer’s assessment of alertness/sedation score than those of the DEX group (P = .041), but after 40 minutes, patients of the MDZ group had a higher score than those of the DEX group throughout surgeries (P = 0.048). The DEX group has less requirements of postoperative morphine/equivalent doses than the MDZ group (4 ± 1 vs 5 ± 1, P < .0001, q = 18.451).

Conclusions:

Intraoperative DEX offers better sedation, postoperative analgesia, and clinical recovery for peripheral surgeries and suppresses inflammatory response.

Level of Evidence:

III.