Perioperative Glycemic Management in Cardiac Surgery: A Narrative Review.

Diabetes and hyperglycemic events in cardiac surgical patients are associated with postoperative morbidity and mortality. The causes of dysglycemia, the abnormal fluctuations in blood glucose concentrations, in the perioperative period include surgical stress, surgical techniques, medications administered perioperatively, and patient factors. Both hyperglycemia and hypoglycemia lead to poor outcomes after cardiac surgery. While trying to control blood glucose concentration tightly for better postoperative outcomes, hypoglycemia is the main adverse event. Currently, there is no definite consensus on the optimum perioperative blood glucose concentration to be maintained in cardiac surgical patients. This review provides an overview of perioperative glucose homeostasis, the pathophysiology of dysglycemia, factors that affect glycemic control in cardiac surgery, and current practices for glycemic control in cardiac surgery.

Adverse Clinical Effects Associated With Non-catecholamine Pharmacologic Agents for Treatment of Vasoplegic Syndrome in Adult Cardiac Surgery.

Vasoplegic syndrome is a relatively common complication that can happen during and after major adult cardiac surgery. It is associated with a higher rate of complications, including postoperative renal failure, longer duration of mechanical ventilation, and intensive care unit stay, as well as increased mortality. The underlying pathophysiology of vasoplegic syndrome is that of profound vascular hyporesponsiveness, and involves a complex interplay among inflammatory cytokines, cellular surface receptors, and nitric oxide (NO) production. The pharmacotherapy approaches for the treatment of vasoplegia include medications that increase vascular smooth muscle contraction via increasing cytosolic calcium in myocytes, reduce the vascular effects of NO and inflammation, and increase the biosynthesis of and vascular response to norepinephrine. Clinical trials have demonstrated the clinical efficacy of non-catecholamine pharmacologic agents in the treatment of vasoplegic syndrome. With an increase in their use today, it is important for clinicians to understand the adverse clinical outcomes and patient risk profiles associated with these agents, which will allow better-tailored medical therapy.

Clinical Approach to Massive Hemoptysis: Perioperative Focus on Causes and Management.

Massive hemoptysis is a time critical airway emergency in the perioperative setting, with an associated mortality exceeding 50%. Causes of hemoptysis in the perioperative setting include procedural complication, coagulopathy, malignancy, chronic lung disease, infection, left-sided cardiac disease, pulmonary vascular disease and autoimmune disease. A rapid and coordinated multidisciplinary response is required to secure the airway, isolate the lung, ensure adequate oxygenation and ventilation, identify the underlying cause and initiate specific systemic, bronchoscopic, endovascular, or surgical treatment. This review examines the etiology, pathophysiology, as well as approach to management and interventions in perioperative massive hemoptysis.

Review of Postoperative Care for Heart Transplant Recipients.

The early postoperative management strategies after heart transplantation include optimizing the function of the denervated heart, correcting the causes of hemodynamic instability, and initiating and maintaining immunosuppressive therapy, allograft rejection surveillance, and prophylaxis against infections caused by immunosuppression. The course of postoperative support is influenced by the quality of allograft myocardial protection prior to implantation and reperfusion, donor-recipient heart size matching, surgical technique of orthotopic heart transplantation, and patient factors (eg, preoperative condition, immunologic compatibility, postoperative vasomotor tone, severity and reversibility of pulmonary vascular hypertension, pulmonary function, mediastinal blood loss, and end-organ perfusion). This review provides an overview of the early postoperative care of recipients and includes a brief description of the surgical techniques for orthotopic heart transplantation.

Anesthesia for Nonintubated Video-Assisted Thoracoscopic Surgery.

With the growing adoption of Enhanced Recovery After Surgery protocols across all surgical groups, including thoracic surgery, coupled with improved video-assisted thoracoscopic surgery (VATS) equipment and techniques, nonintubated thoracoscopic surgery has gained significant popularity in recent years. Avoiding tracheal intubation with an endotracheal or double-lumen tube and general anesthesia may reduce or eliminate the risks associated with traditional mechanical ventilation, one-lung ventilation, and general anesthesia. Studies have shown a trend toward better preservation of postoperative respiratory function and improved postoperative lengths of hospital stay, morbidity, and mortality; however, these have not been conclusively proven. This review article discusses the advantages of nonintubated VATS, the types of thoracic surgery in which this technique has been described, patient selection, appropriate anesthetic techniques, surgical concerns, potential complications relevant to the anesthesiologist during the conduct of nonintubated VATS surgery, and suggested management of these complications.

Preoperative Evaluation and Care of Heart Transplant Candidates.

Heart transplantation is recommended for patients with advanced heart failure refractory to medical and device therapy, and who do not have absolute contraindications. When patients become eligible for heart transplantation, they undergo comprehensive evaluation and preparation to optimize their posttransplantation outcomes. This review provides an overview of the processes that are employed to enable the candidates to be transplant-ready when donor hearts are available.

Infection Control for Perioperative Ultrasonography and Echocardiography.

Ultrasound technology has revolutionized point-of-care diagnostics, decision-making, and the guidance of interventional procedures in Anesthesiology and Perioperative Medicine. Recent literature has highlighted important infection control considerations when performing transesophageal or transthoracic echocardiography, point-of-care ultrasound, and ultrasound-guided procedures. This narrative review focuses on operator precautions and disinfection methods and summarizes key recommendations from the international Echocardiography and Radiology Societies.

Heparin Resistance During Cardiopulmonary Bypass in Adult Cardiac Surgery.

The use of heparin for anticoagulation has changed the face of cardiac surgery by allowing a bloodless and motionless surgical field throughout the introduction of cardiopulmonary bypass (CPB). However, heparin is a drug with complex pharmacologic properties that can cause significant interpatient differences in terms of responsiveness. Heparin resistance during CPB is a weighty issue due to the catastrophic consequences stemming from inadequate anticoagulation, and the treatment of it necessitates a rationalized stepwise approach due to the multifactorial contributions toward this entity. The widespread use of activated clotting time (ACT) as a measurement of anticoagulation during CPB is examined, as it may be a false indicator of heparin resistance. Heparin resistance also has been repeatedly reported in patients infected with COVID-19, which deserves further exploration in this pandemic era. This review aims to examine the variability in heparin potency, underlying mechanisms, and limitations of using ACT for monitoring, as well as provide a framework towards the current management of heparin resistance.

Six-Month Outcomes after Restrictive or Liberal Transfusion for Cardiac Surgery.

BACKGROUND: We reported previously that, in patients undergoing cardiac surgery who were at moderate-to-high risk for death, a restrictive transfusion strategy was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis by hospital discharge or 28 days after surgery, whichever came first. We now report the clinical outcomes at 6 months after surgery. METHODS: We randomly assigned 5243 adults undergoing cardiac surgery to a restrictive red-cell transfusion strategy (transfusion if the hemoglobin concentration was <7.5 g per deciliter intraoperatively or postoperatively) or a liberal red-cell transfusion strategy (transfusion if the hemoglobin concentration was <9.5 g per deciliter intraoperatively or postoperatively when the patient was in the intensive care unit [ICU] or was <8.5 g per deciliter when the patient was in the non-ICU ward). The primary composite outcome was death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis occurring within 6 months after the initial surgery. An expanded secondary composite outcome included all the components of the primary outcome as well as emergency department visit, hospital readmission, or coronary revascularization occurring within 6 months after the index surgery. The secondary outcomes included the individual components of the two composite outcomes. RESULTS: At 6 months after surgery, the primary composite outcome had occurred in 402 of 2317 patients (17.4%) in the restrictive-threshold group and in 402 of 2347 patients (17.1%) in the liberal-threshold group (absolute risk difference before rounding, 0.22 percentage points; 95% confidence interval [CI], -1.95 to 2.39; odds ratio, 1.02; 95% CI, 0.87 to 1.18; P=0.006 for noninferiority). Mortality was 6.2% in the restrictive-threshold group and 6.4% in the liberal-threshold group (odds ratio, 0.95; 95% CI, 0.75 to 1.21). There were no significant between-group differences in the secondary outcomes. CONCLUSIONS: In patients undergoing cardiac surgery who were at moderate-to-high risk for death, a restrictive strategy for red-cell transfusion was noninferior to a liberal strategy with respect to the composite outcome of death from any cause, myocardial infarction, stroke, or new-onset renal failure with dialysis at 6 months after surgery. (Funded by the Canadian Institutes of Health Research and others; TRICS III ClinicalTrials.gov number, NCT02042898 .).

Red-Colored Urine in the Cardiac Surgical Patient-Diagnosis, Causes, and Management.

Red-colored urine occurring in the intraoperative and early postoperative periods after cardiac surgery is often a cause for concern. This observation may be a result of hematuria from pathology within the urinary tract, anticoagulant-related nephropathy, drug-induced acute interstitial nephropathy, excretion of heme pigment-containing proteins, such as myoglobin and hemoglobin, and hemolysis occurring during extracorporeal circulation. Within the kidneys, heme-containing compounds result in pigment nephropathy, which is a significant contributory factor to cardiac surgery-associated acute kidney injury. Concerted efforts to reduce red blood cell damage during cardiopulmonary bypass, together with early recognition of the at-risk patient and the institution of prompt therapeutic intervention, may improve outcomes. This review addresses the diagnosis, causes, and management of red-discolored urine occurring during and after cardiac surgery.

Sodium Abnormalities in Cardiac Surgery With Cardiopulmonary Bypass in Adults: A Narrative Review.

Perioperative sodium abnormalities or dysnatremia is not uncommon in patients presenting for cardiac surgery and is associated with increased morbidity and mortality. Both the disease process of heart failure and its treatment may contribute to abnormalities in serum sodium concentration. Serum sodium is the main determinant of serum osmolality, which in turn affects cell volume. Brain cells are particularly vulnerable to changes in serum osmolality because of the nondistensible cranium. The potentially catastrophic neurologic sequelae of rapidly correcting chronic dysnatremia and the time-sensitive nature of cardiac surgery can make the management of these patients challenging. The use of cardiopulmonary bypass to facilitate surgery adds another layer of complexity in the intraoperative management of sodium and water balance. This narrative review examines the definition and classification of dysnatremia. It also covers the etiology and pathophysiology of dysnatremia, implications during cardiac surgery requiring cardiopulmonary bypass, and the perioperative management of dysnatremia.

Volatile Anesthesia Versus Total Intravenous Anesthesia During Cardiopulmonary Bypass: A Narrative Review on the Technical Challenges and Considerations.

The Mortality in Cardiac Surgery Randomized Controlled Trial of Volatile Anesthetics (MYRIAD) demonstrated that cardiac surgery with either volatile anesthesia or intravenous anesthesia techniques can be comparable with respect to morbidity and mortality. Maintaining anesthesia during cardiopulmonary bypass (CPB) with either approach requires appreciation of the nuances that are unique to each. This narrative review addresses these technical challenges and other considerations.

Strategies for Left Ventricular Decompression During Venoarterial Extracorporeal Membrane Oxygenation - A Narrative Review.

Extracorporeal cardiopulmonary resuscitation involves the application of venoarterial extracorporeal membrane oxygenation for patients in cardiac arrest who have received good quality conventional cardiopulmonary resuscitation, and who are deemed to have a reversible cause and no contraindications. Systemic perfusion is maintained by the extracorporeal life support, allowing time for the underlying cause to be treated and the heart to recover. Specific considerations to promote cardiac recovery are discussed, including the maintenance of sinus rhythm, promotion of cardiac ejection, management of pulmonary hypertension, management of intravascular volume, and prevention of ventricular distention. Advanced strategies for ventricular decompression including atrial septostomy and percutaneous ventricular assist devices are discussed.

Deep Sternal Wound Infection: Diagnosis, Treatment and Prevention.

Deep sternal wound infection (DSWI) is a rare but potentially devastating complication of median sternotomy performed in cardiac surgery. The incidence of DSWI is reported to be between 0.2% and 3%. Identifying high-risk patients and strategies to optimize risk factors plays an important role in reducing the incidence of DSWI. Management of DSWI can be complex and may require a multidisciplinary team approach involving infectious disease specialists, microbiologists, as well as cardiothoracic and plastic surgeons. Early detection, appropriate antibiotic treatment, aggressive surgical debridement, and use of regional muscle flaps have significantly improved treatment outcomes.

Grit protects medical students from burnout: a longitudinal study.

BACKGROUND: Burnout is a serious issue plaguing the medical profession with potential negative consequences on patient care. Burnout symptoms are observed as early as medical school. Based on a Job Demands-Resources model, this study aims to assess associations between specific job resources measured at the beginning of the first year of medical school with burnout symptoms occurring later in the first year. METHODS: The specific job resources of grit, tolerance for ambiguity, social support and gender were measured in Duke-NUS Medical School students at the start of Year 1. Students were then surveyed for burnout symptoms at approximately quarterly intervals throughout the year. Using high ratings of cynicism and exhaustion as the definition of burnout, we investigated the associations of the occurrence of burnout with student job resources using multivariable logistic regression analysis. RESULTS: Out of 59 students, 19 (32.2%) indicated evidence of burnout at some point across the first year of medical school. Stepwise multivariable logistic regression analysis identified grit as having a significant protective effect against experiencing burnout (Odds Ratio, 0.84; 95%CI 0.74 to 0.96). Using grit as a single predictor of burnout, area under the ROC curve was 0.76 (95%CI: 0.62 to 0.89). CONCLUSIONS: Grit was identified as a protective factor against later burnout, suggesting that less gritty students are more susceptible to burnout. The results indicate that grit is a robust character trait which can prognosticate burnout in medical students. These students would potentially benefit from enhanced efforts to develop grit as a personal job resource.

Acute Kidney Injury After Cardiac Surgery: A Narrative Review of the Literature.

Acute kidney injury (AKI) is a common and serious complication of cardiac surgery. It is associated with increased morbidity and mortality. On a population level, the financial impact and overall incremental annual index hospitalization costs associated with AKI exceed $1 billion in the United States alone. The pathogenesis is multifaceted and complex. Although novel biomarkers may be useful in detecting AKI at an earlier stage, treatment of AKI remains elusive. Prevention of AKI is still key to the management of AKI, and strategies include maintenance of renal perfusion and avoidance of nephrotoxins and blood transfusion-related insults. Dialysis in severe AKI is established, but the optimal modality and dose remains an area of ongoing research. This narrative review assesses the pathophysiology of AKI, role of biomarkers, risk assessment, and management in cardiac surgical patients.

History and Current Status of Cardiac Anesthesia in Singapore.

Singapore is a small Southeast Asian island city-state located at the tip of the Malay peninsula with a population of 5.61 million people. It was a former British colony that went on to become a part of Malaysia before gaining independence in 1965. Since then, Singapore has developed tremendously from a small fishing village into the region's medical hub. This article will explore the roots of cardiac anesthesia in Singapore and how it has developed into a subspecialty today.