Mayo Clinic College of Medicine - Rochester

Mayo Clinic: Department of Anesthesiology and Perioperative Medicine

The Department of Anesthesiology and Perioperative Medicine-Research at Mayo Clinic conducts a wide range of research related to anesthetic techniques, perioperative medicine and pain management.

Investigators in the department have diverse research interests, ranging from very basic investigations of anesthetic effects on subcellular function to advanced clinical projects that have a direct impact on patient care, such as reducing the need for perioperative transfusions and improving the management of chronic pain.

With an extensive multidisciplinary faculty, the Department of Anesthesiology and Perioperative Medicine-Research is developing cutting-edge technologies in anesthesiology, including the use of gene therapy to treat cardiovascular disease in the perioperative period. The department engages in collaborative research with numerous Mayo Clinic physicians and scientists on a broad spectrum of conditions that benefit from improved anesthetic techniques and pain management or that require specialized care, including anesthesiology use in obstetrics and pediatrics.

The Department of Anesthesiology and Perioperative Medicine-Research seeks a better understanding of genomics, proteomics, lung biology, pharmacology and other basic science related to anesthesia to ultimately improve outcomes for patients in need of anesthesia and pain management.

RESIDENT TRAINING/ORIENTATION

Huang J, Licatino LK, Ocariz S, Warner PA, Sims CR 3rd. A Novel Approach to Emergency Airway Simulation Using a 3D-printed Cricothyrotomy Task Trainer. J Educ Perioper Med. 2021 Jul 1;23(3):E670. doi: 10.46374/volxxiii_issue3_sims. PMID: 34631968; PMCID: PMC8491648.

Cricothyrotomy is an essential skill as the final recourse for salvaging a difficult airway, yet most anesthesiology providers have little training, exposure, or comfort with the procedure. Pig tracheas are frequently used for cricothyrotomy training, but are single-use and require special handling and storage. Other simulation models such as mannequins and cadavers are costly. Advances in three-dimensional (3D) printing have improved accessibility and decreased costs. This research project found that an inexpensive 3D printed task trainer was noninferior to pig tracheas for teaching surgical cricothyrotomy skills to anesthesiology residents. A 3D-printed model offers a viable alternative to pig tracheas for emergency airway simulation that is inexpensive, reusable, and readily modified to simulate challenging airway anatomy.

CARDIOVASULAR ANESTHESIOLOGY

Ashikhmina E, Schaff HV, Daly RC, Stulak JM, Greason KL, Michelena HI, Fatima B, Lahr BD, Dearani JA. Risk factors and progression of systolic anterior motion after mitral valve repair. J Thorac Cardiovasc Surg. 2021 Aug. DOI: https://doi.org/10.1016/j.jtcvs.2019.12.106

Objectives: The phenomenon of systolic anterior motion (SAM) of the mitral valve (MV) was discovered 50 years ago, but to date only a few studies have identified risk factors for SAM following mitral repair. There are limited data on the necessity of surgical reintervention on the MV once SAM is discovered by intraoperative transesophageal echocardiography. We sought to identify predictors of SAM in a large cohort of consecutive patients, assess the rate of early reintervention on the MV to address SAM, and follow the progression of SAM postdischarge.

Conclusions: Transesophageal echocardiography findings associated with SAM were excessive height of posterior to anterior mitral leaflet, smaller left ventricular end-systolic volume, and bileaflet prolapse. Conservative management of SAM was usually successful, and persistent hemodynamically significant SAM was uncommon. Prophylactic modification of the surgical technique to avoid SAM seems unnecessary for all but those at highest risk for developing SAM.

Carvalho JL, Ashikhmina E, Abel MD, Viehman JK, Lahr BD, Geske JB, Schaff HV. Hypertrophic Obstructive Cardiomyopathy: Discrepancy Between Hemodynamic Measurements in the Cardiac Laboratory and Operating Room Is to Be Expected. J Cardiothorac Vasc Anesth. 2021 May. DOI: https://doi.org/10.1053/j.jvca.2021.05.041

Objectives: It is not uncommon to observe some discrepancy in hemodynamic values characterizing left ventricular outflow tract (LVOT) obstruction preoperatively and in the operating room in patients with hypertrophic obstructive cardiomyopathy. Interpretation of this discrepancy can be challenging. To clarify the extent of the discrepancy, we compared hemodynamic variables in patients undergoing septal myectomy at the time of preoperative and intraoperative evaluation.

Conclusions: Discrepancy between hemodynamic measurements in the cardiac laboratory and operating room is common and generally should not affect planned patients' care. These changes in hemodynamics might be explained by preoperative fasting, anesthetic agents, volume shifts while supine, and positive-pressure ventilation, as well as the difference in measurement techniques.

Stephens EH, Qureshi MY, Anderson JH, Ashikhmina E, Dearani JA. Bidirectional Cavopulmonary Shunt for Right Ventricular Unloading. Ann Thorac Surg. 2021 May;111(5):1435-1441. DOI: https://doi.org/10.1016/j.athoracsur.2020.06.037

Right-sided heart failure remains a challenge in the care of congenital heart disease patients, both those with right ventricular dilation and dysfunction and those with right ventricular hypoplasia. Two strategies for treatment are atrial septal fenestration and bidirectional cavopulmonary shunt (BCPS). When used strategically in select patients, BCPS and atrial-level fenestration are effective in managing right ventricular failure in congenital heart disease patients. Preoperative imaging and intraoperative anatomic and physiologic factors help guide the appropriate management for a given patient.

PATIENT OUTCOMES

Johnson RL, Frank RD, Abdel MP, Habermann EB, Chamberlain AM, Mantilla CB. Frailty Transitions One Year After Total Joint Arthroplasty: A Cohort Study. J Arthroplasty. Epub 2021 Sept 01. PMID: 34531097.

Frailty represents the inability to restore one’s usual state of health after an event such as surgery. Total joint arthroplasty (TJA) is prevalent and TJA is offered to patients regardless of frailty status. This retrospective cohort study examined whether TJA would lessen frailty and to what extent TJA could impact frailty transition states. In total 5,341 patients were identified from an institutional registry. Preoperatively all patients were measured via the frailty deficit index, the group comprised of 37.6% non-frail patients, 39.4 % vulnerable, and 23.0% frail. One year after TJA, 29.0 % of vulnerable patients improved to non-frail and 11.0 % regressed to frail. Forty percent of frail patients improved to vulnerable/non-frail status. Improvements in activities of daily living were more evident in frail and vulnerable patients, with > 30% reduction in the percentage of patients expressing difficulties with walking, climbing stairs, and needing help with activities one year after TJA. Frailty at one year was associated with significantly increased rates of mortality, periprosthetic joint infection, and reoperation. In summary, frailty states are dynamic with patient frailty shown to be modifiable one year after TJA. Preoperative frailty measurement is an important step toward identifying those that may benefit most from TJA and for postoperative frailty surveillance.

CRITICAL CARE MEDICINE

Seelhammer TS, Bohman JK, Schulte Phillip, Hanson AC, Aganga DO. Comparison of bivalirudin versus heparin for maintenance systemic anticoagulation during adult and pediatric extracorporeal membrane oxygenation. Crit Care Med. 2021 Sep;49(9):1481-1492. DOI: 10.1097/CCM.0000000000005033. PMID: 33870916.

In extracorporeal membrane oxygenation (ECMO), the extensive foreign material surface area present within the ECMO circuit (membrane oxygenator, pump, and tubing) necessitates systemic anticoagulation to avoid thromboembolic and hemorrhagic complications, which challenges ECMO runs in 10–30% of cases. When compared to the conventional approach with heparin, bivalirudin offers several important advantages including a direct mechanism of action acting independent of a cofactor such as antithrombin, the ability to act on soluble and clot bound thrombin, and a short clinical half-life of approximately 25 minutes. In this retrospective chart review study of 424 adult and pediatric ECMO patients the use of bivalirudin was associated with reduced mortality in the adult group (odds ratio 0.39; p < 0.01) and a reduction in the composite transfusion requirement in the first 24 hours in the pediatric group (odds ratio 0.28; p < 0.02). Groups did not differ regarding laboratory studies per day, anticoagulant dose adjustments, or ischemic complications. These findings demonstrate the feasibility and safety of bivalirudin for systemic anticoagulation in patients supported on ECMO as established by the absence of increases in identifiable adverse outcomes while manifesting substantial improvements in hospital mortality in adult patients receiving bivalirudin versus those receiving heparin.

PEDIATRIC ANESTHESIA

Thalji L, Thalji NM, Heimbach JK, Ibrahim SH, Kamath PS, Hanson A, Schulte PJ, Haile DT, Kor DJ. Renal Function Parameters and Serum Sodium Enhance Prediction of Wait-List Outcomes in Pediatric Liver Transplantation. Hepatology. 2021 Mar;73(3):1117-1131. doi: 10.1002/hep.31397.Hepatology. 2021. PMID: 32485002

Reliance on exception points to prioritize children for liver transplantation (LT) stems from concerns that the Pediatric End-Stage Liver Disease (PELD) score underestimates mortality. Renal dysfunction and serum sodium disturbances are negative prognosticators in adult LT candidates and various pediatric populations, but are not accounted for in PELD. We retrospectively evaluated the effect of these parameters in predicting 90-day wait-list death/deterioration among pediatric patients (<12 years) listed for isolated LT in the United States between February 2002 and June 2018. Listing eGFR, dialysis, and serum sodium are potent, independent predictors of 90-day death/deterioration in pediatric LT candidates, capturing risk not accounted for by PELD. Incorporation of these variables into organ allocation systems may highlight patient subsets with previously underappreciated risk, augment ability of PELD to prioritize patients for transplantation, and ultimately mitigate reliance on nonstandard exceptions.

PERIOPERATIVE ANESTHESIA

Warner MA, Meyerhoff KL, Warner ME, Posner KL, Stephens L, Domino KB. Pulmonary Aspiration of Gastric Contents: A Closed Claims Analysis. Anesthesiology. 2021 Aug 1;135(2):284-291. doi: 10.1097/ALN.0000000000003831. PMID: 34019629.

Perioperative pulmonary aspiration of gastric contents continues to be associated with severe morbidity and death despite advances in relevant guidelines and airway management. In this review of the American Society of Anesthesiologists’ Closed Claims Project and its reports of perioperative pulmonary aspiration, the authors found that death and permanent severe injury were common outcomes. Five percent of all Closed Claims in the project’s database involved perioperative pulmonary aspiration. More than two of every three patients who experienced pulmonary aspiration of gastric contents died or suffered permanent severe injury as a direct consequence of it. The majority of patients who aspirated had either gastrointestinal obstruction or another acute intraabdominal process. Anesthetic management was judged to be substandard in nearly three of every five claims. These findings suggest that clinical practice modifications to preoperative assessment and anesthetic management of patients at risk for pulmonary aspiration may lead to improvement of their perioperative outcomes.

POSTOPERATIVE ANESTHESIA

Driver CN, Laporta ML, Bergese SD, Urman RD, Di Piazza F, Overdyk FJ, Sprung J, Weingarten TN. Frequency and Temporal Distribution of Postoperative Respiratory Depressive Events. Anesth Analg. 2021 May 1;132(5):1206-1214. doi: 10.1213/ANE.0000000000005478. PMID: 33857962.

This study utilized data from the PRODIGY trial to determine the temporal relationship between the end of surgery and the development of respiratory depression. What was found that respiratory depressive episodes (usually apnea) began to occur in the first few hours of admission to the general post-surgical wards. These events continued with peak occurrence occurring in the early morning hours. These observations have important implications when developing postoperative monitoring protocols, namely these should be initiated upon PACU discharge and continued at least until the next postoperative day.

COAGULATION THERAPY

Yuk H, Wu J, Sarrafian TL, Mao X, Varela CE, Roche ET, Griffiths LG, Nabzdyk CS, Zhao X. Rapid and coagulation-independent haemostatic sealing by a paste inspired by barnacle glue. Nat Biomed Eng. 2021 Oct;5(10):1131-1142. doi: 10.1038/s41551-021-00769-y. Epub 2021 Aug 9. PMID: 34373600.

Tissue adhesives do not normally perform well on tissues that are covered with blood or other bodily fluids. Here we report the design, adhesion mechanism and performance of a paste that haemostatically seals tissues in less than 15 s, independently of the blood-coagulation rate. With a design inspired by barnacle glue (which strongly adheres to wet and contaminated surfaces owing to adhesive proteins embedded in a lipid-rich matrix), the paste consists of a blood-repelling hydrophobic oil matrix containing embedded microparticles that covalently crosslink with tissue surfaces on the application of gentle pressure. It slowly resorbs over weeks, sustains large pressures (approximately 350 mm Hg of burst pressure in a sealed porcine aorta), makes tough (interfacial toughness of 150-300 J m-2) and strong (shear and tensile strengths of, respectively, 40-70 kPa and 30-50 kPa) interfaces with blood-covered tissues, and outperforms commercial haemostatic agents in the sealing of bleeding porcine aortas ex vivo and of bleeding heart and liver tissues in live rats and pigs. The paste may aid the treatment of severe bleeding, even in individuals with coagulopathies.