Dexmedetomidine and surgical field visibility in nasal surgery: A systematic review and meta-analysis.

INTRODUCTION: Nasal and sinus surgery, especially using endoscopy, relies upon adequate haemostasis to be safe and effective. Often other haemostatic methods, such as cautery are not viable, and other methods must be employed. This study examines the effectiveness of dexmedetomidine in controlled hypotension and for surgical field visibility in endoscopic sinus surgery and other nasal surgeries. REVIEW METHODS: A literature search was conducted in PubMed, Scopus, CINAHL and Central for randomised controlled trials using dexmedetomidine for controlled hypotension in adult patients undergoing endoscopic sinus surgery or other nasal surgery. Meta-analysis of mean differences and single means were performed. RESULTS: Of 935 identified studies, 31 met the inclusion criteria. A statistically significant difference in Fromme-Boezaart surgical field visibility scores was found comparing dexmedetomidine to placebo (p < 0.00001) and propofol (p < 0.0001), but not other agents. A significant difference in intraoperative blood loss volume was found compared with placebo (51.5mL, p < 0.00001) and propofol (13.6mL, p < 0.0001), but not other agents. CONCLUSION: Dexmedetomidine demonstrated significantly improved surgical field visibility and blood loss volume compared with placebo and propofol, but not other agents. Dexmedetomidine is viable and useful for controlled hypotension in nasal surgery. Choice of controlled hypotension agent should follow patient and procedure-specific considerations.

Normalizing arterial blood pressure in patients with aortic stenosis does not prevent grading discrepancies between pre-cardiopulmonary bypass transesophageal echocardiography and transthoracic echocardiography.

Background: Aortic stenosis (AS) grading discrepancies exist between pre-cardiopulmonary (pre-CPB) transesophageal echocardiography (TEE) and preoperative transthoracic echocardiography (TTE). Prior studies have not systematically controlled blood pressure. Aims: We hypothesized that normalizing arterial blood pressure during pre-CPB TEE for patients undergoing valve replacement for AS would result in equivalent grading measurements when compared to TTE. Setting: Single University Hospital. Design: Prospective, Interventional. Methods: Thirty-five adult patients underwent procedures for valvular AS between February 2017 and December 2020 at Medical University of South Carolina. Study participants had a TTE within 90 days of their procedure that documented blood pressure, peak velocity (Vp), mean gradient (PGm), aortic valve area (AVA), and dimensionless index (DI). During pre-CPB TEE, if a patient's mean arterial pressure (MAP) fell more than 20% below their baseline blood pressure obtained during TTE, measurements were recorded as "out of range." Phenylephrine was administered to restore MAP to the baseline range and repeat TEE measurements were recorded as "in-range." Statistical Analysis: Differences between imaging modalities and grading parameters were examined using a series of linear mixed models. P values were Bonferroni-adjusted to account for multiple comparisons. Main Results: Significant discrepancies between TEE and TTE were observed for Vp, PGm, and DI despite blood pressure normalization across all subjects and for out-of-range measures and corrected measures. There were no statistically significant differences between TEE and TTE for AVA. Conclusions: Blood pressure normalization during pre-CPB TEE is not sufficient to avoid AS grading discrepancies with preoperative TTE.

Use of dexmedetomidine for controlled hypotension in middle ear surgery: A systematic review and meta-analysis.

BACKGROUND: Microsurgical operations such as middle ear surgery rely heavily on visibility of the surgical field. Anesthetic techniques such as controlled hypotension have been developed to improve surgical field visibility by attempting to decrease bleeding. Many agents have been utilized to achieve controlled hypotension intraoperatively. Dexmedetomidine is a relatively newer agent which works on alpha-2 receptors to decrease sympathetic tone. This paper sought to determine the efficacy of dexmedetomidine for optimizing surgical field visibility in MES. METHODS: A comprehensive search strategy was used in PubMed, SCOPUS, CINAHL, and CENTRAL through August 9, 2022 for this systematic review and meta-analysis. INCLUSION CRITERIA: adult patients undergoing middle ear surgery with dexmedetomidine used for controlled hypotension to improve surgical field visibility. Risk of bias was assessed via Cochrane RoB 2. Meta-analysis of mean difference for surgical field scores and risk ratios for positive surgical field scores were used to compare dexmedetomidine with placebo or other agents. RESULTS: Fourteen studies were included in this review. Statistically significant mean difference was found to favor dexmedetomidine over placebo for Fromme-Boezaart surgical field scores. Statistically significant results were also demonstrated favoring dexmedetomidine over other agents in risk ratio for receiving positive surgical field scores, as well as surgeon and patient satisfaction scores. CONCLUSIONS: Controlled hypotension is an invaluable tool for surgical field visibility. Improved surgical field visibility was observed with dexmedetomidine compared with placebo and various other agents. Risk of sub-optimal bleeding scores was significantly lower with dexmedetomidine. Dexmedetomidine is effective at improving surgical field visibility in middle ear surgery.

Results of a Flipped Classroom Teaching Approach in Anesthesiology Residents.

BACKGROUND: In a flipped classroom approach, learners view educational content prior to class and engage in active learning during didactic sessions. OBJECTIVE: We hypothesized that a flipped classroom improves knowledge acquisition and retention for residents compared to traditional lecture, and that residents prefer this approach. METHODS: We completed 2 iterations of a study in 2014 and 2015. Institutions were assigned to either flipped classroom or traditional lecture for 4 weekly sessions. The flipped classroom consisted of reviewing a 15-minute video, followed by 45-minute in-class interactive sessions with audience response questions, think-pair-share questions, and case discussions. The traditional lecture approach consisted of a 55-minute lecture given by faculty with 5 minutes for questions. Residents completed 3 knowledge tests (pretest, posttest, and 4-month retention) and surveys of their perceptions of the didactic sessions. A linear mixed model was used to compare the effect of both formats on knowledge acquisition and retention. RESULTS: Of 182 eligible postgraduate year 2 anesthesiology residents, 155 (85%) participated in the entire intervention, and 142 (78%) completed all tests. The flipped classroom approach improved knowledge retention after 4 months (adjusted mean = 6%; P = .014; d = 0.56), and residents preferred the flipped classroom (pre = 46%; post = 82%; P < .001). CONCLUSIONS: The flipped classroom approach to didactic education resulted in a small improvement in knowledge retention and was preferred by anesthesiology residents.

Impact of continuous paravertebral blockade infusion type on pain management over time for video-assisted thoracoscopic surgery: a pilot study.

This pilot study was designed to examine the impact of two different (PVB) infusion types compared to a control (no PVB) on pain management in video-assisted thoracoscopic surgery. Acute and chronic pain over time, perioperative oral morphine milligram equivalent (MME) consumption and patient satisfaction were measured. A protracted enrollment period and participant attrition precluded target enrollment and subsequent power analysis. Further, there was no increased efficacy of the intervention groups over the control group. In fact, the patient-controlled analgesia only group (control) had lower mean and median MME consumption postoperatively. Pain and patient satisfaction scores were similar among all treatment groups at all time points assessed. We characterize our study population, report our results for each treatment group and highlight challenges encountered and lessons learned to aid in the development of future research.

Echocardiography in the intensive care unit.

As ultrasound technology improves and ultrasound availability increases, echocardiography utilization is growing within intensive care units. Although not replacing the often-needed comprehensive echocardiographic evaluation, limited bedside echocardiography promises to provide intensivists with enhanced diagnostic ability and improved hemodynamic understanding of individual patients. Routine and emergency echocardiography within the intensive care unit focuses on identifying and optimizing medically treatable conditions in a timely manner. Methods for such goal-directed assessments are presented.