Cardiac surgery during the COVID-19 sine wave: Preparation once, preparation twice. A view from Houston.

The novel coronavirus disease (COVID-19) pandemic has created major challenges and disruptions to hospitals throughout the world, with profound implications for cardiac surgery and cardiac surgeons. In this review, we highlight the hospital and cardiac surgical experience at Baylor St. Luke's Medical Center in the Texas Medical Center in Houston, Texas as of mid-July 2020. Our local experience has consisted of a spring surge (early March to early May), followed by a relative flattening and then a summer surge (early June to present day), similar to a sine wave. Throughout the entire pandemic, our simultaneous medical priorities have been treating the growing number of patients with COVID-19 while continuing to provide needed care for those without COVID-19. The current situation will be the "new normal" until a vaccine becomes available. It will be vital to stay attuned to epidemiologists, public health officials, and infection control experts, because what they see today, the intensive care units will see tomorrow. The lessons we have learned are outlined in this review but can be summarized most succinctly: preparation. We must prepare in advance, stockpile supplies and personal protective equipment, have rapid and vigorous testing protocols in place, utilize technology (eg, online meetings, videoconference "office visits"), and encourage hospital-wide and community protective efforts (social distancing, mask wearing, hand hygiene). Hopefully, the lessons learned through this challenging experience will prepare us for the next time.

Anesthetic Management of Laser Lead Extraction for Cardiovascular Implantable Electronic Devices.

Cardiovascular implantable electronic devices (CIEDs) play a significant role in the modern management of cardiovascular disease. CIEDs include implantable pacemakers (PMs), implantable cardioverter-defibrillators (ICDs), and cardiac resynchronization therapy (CRT) devices. These devices improve the quality of life of their recipients and help reduce the incidence of sudden cardiac death. Traditionally, CIEDs have been reliant on the use of transvenous endocardial leads to directly connect with the heart. Over time, these endovascular leads may become endothelialized rendering removal extremely difficult. As the indications for CIEDs expands and with the continuing evolution of these devices, the number of patients requiring explantation for device recall, malfunction, and infection continues to increase. In this manuscript, we review the most common CIEDs, the indications and process of lead removal/device explantation, potential complications associated with the procedure and the anesthetic management of these patients.

Anesthetic Management of Patients Undergoing Percutaneous Endocardial and Epicardial Left Atrial Appendage Occlusion.

Atrial fibrillation is the most common cardiac arrhythmia in adults affecting almost 6 million adults in the United States. The 2 most common comorbidities associated with atrial fibrillation are heart failure and thromboembolic events. Heart failure symptoms may be treated with rate control, antiarrhythmic medications or by catheter ablation. Unfortunately, despite optimal medical management, thromboembolic events still occur. Recently, there has been a great deal of interest and innovation in finding an alternative to chronic anticoagulation. Several percutaneous left atrial appendage occlusion devices have been developed over recent years, some of which have proven to be noninferior to anticoagulation in preventing strokes in atrial fibrillation patients. The 2 most widely used left atrial appendage occlusion devices are the WATCHMAN (Atritech Inc, Plymouth, MN, USA) and the LARIAT (SentreHEART, Palo Alto, CA, USA) devices. After a detailed description of the procedures, the anesthetic considerations of each procedure and management of specific adverse events are discussed within this review.

Anesthetic Management in Radiofrequency Catheter Ablation of Ventricular Tachycardia.

Radiofrequency catheter ablation is increasingly being used to treat patients who have ventricular tachycardia, and anesthesiologists frequently manage their perioperative care. This narrative review is intended to familiarize anesthesiologists with preprocedural, intraprocedural, and postprocedural implications of this ablation. Ventricular tachycardia typically arises from structural heart disease, most often from scar tissue after myocardial infarction. Many patients thus affected will benefit from radiofrequency catheter ablation in the electrophysiology laboratory to ablate the foci of arrhythmogenesis. The pathophysiology of ventricular tachycardia is complex, as are the technical aspects of mapping and ablating these arrhythmias. Patients often have substantial comorbidities and tenuous hemodynamic status, necessitating pharmacologic and mechanical cardiopulmonary support. General anesthesia and monitored anesthesia care, when used for sedation during ablation, can lead to drug interactions and side effects in the presence of ventricular tachycardia, so anesthesiologists should also be aware of potential perioperative complications. We discuss variables that can help anesthesiologists safely guide patients through the challenges of radiofrequency catheter ablation of ventricular tachycardia.

Early detection of a cavopulmonary tumor embolus with the use of transesophageal echocardiography.

Pulmonary tumor embolization from renal cell carcinoma is associated with severe cardiopulmonary morbidity and high perioperative mortality rates. We report the case of a 71-year-old woman who presented with right-sided abdominal pain. Magnetic resonance images revealed a mass originating from the upper pole of the right kidney and extending into the infrahepatic portion of the inferior vena cava. Transesophageal echocardiography was continuously used to monitor the mass during intended radical nephrectomy and tumor resection. When the right kidney was mobilized, intracaval thrombus detached and migrated to the patient's right atrium, causing severe hemodynamic instability. After emergent sternotomy and during the initiation of cardiopulmonary bypass, the mass was no longer echocardiographically detectable in the heart; it was soon removed completely from the left pulmonary artery. The mass was a renal cell carcinoma. We recommend the use of transesophageal echocardiography as an efficient diagnostic tool in the early detection of pulmonary tumor embolization during the resection of renal cell carcinoma that involves the inferior vena cava.

Perioperative management of lower extremity revascularization.

Patients presenting for lower extremity revascularization often have multiple systemic comorbidities, making them high-risk surgical candidates. Neuraxial anesthesia and general anesthesia are equivocal in their effect on perioperative cardiac morbidity and improved graft patency. Postoperative epidural analgesia may improve perioperative cardiac morbidity. Systemic antithrombotic and anticoagulation therapy is common among this patient population and may affect anesthetic techniques.

Contributions of anesthesiology to the surgical treatment of cerebrovascular disease: the role of Arthur S. Keats, M.D.

Increased tolerance to cerebral ischemia produced by general anesthesia during temporary carotid occlusion. By B. A. Wells, A. S. Keats, and D. A. Cooley. Surgery 1963; 54:216-23. Local anesthesia with little or no preoperative sedation is currently recommended as the anesthetic of choice for temporary carotid occlusion during carotid endarterectomy. Purported advantages include minimal circulatory and respiratory changes from the local anesthetic, and constant verbal contact can be maintained with the patient so that neurologic changes are promptly recognized. However, local anesthesia may not be satisfactory in uncooperative or semiconscious patients. We therefore undertook a trial of general anesthesia in 56 consecutive patients undergoing carotid endarterectomy. Patients were induced in standardized fashion using intravenous thiopental (100-400 mg), atropine (0.2 mg), and succinylcholine (40-80 mg). Cyclopropane, along with deliberate hypercapnia and hypertension, was used for anesthesia maintenance. All patients tolerated carotid occlusion for periods of up to 30 min during general anesthesia without shunt, bypass, or hypothermia. Except for one patient, electroencephalogram evidence of cerebral ischemia was not apparent during occlusion, and no patient suffered postoperative neurologic sequela. Twenty percent of patients who had their carotid arteries occluded preoperatively for 30-60 s without general anesthesia suffered convulsions. These data suggest that general anesthesia increased the tolerance to cerebral ischemia. Potential mechanisms involved might include: 1) decreased cerebral metabolic rate for oxygen; 2) increased cerebral blood flow from hypercapnia; 3) increased arterial oxygen tension; and 4) recruitment of new routes of collateral circulation.