Role of Cardiac Anesthesiologists in Intraoperative Enhanced Recovery After Cardiac Surgery (ERACS) Protocol: A Retrospective Single-Center Study Analyzing Preliminary Results of a Yearlong ERACS Protocol Implementation

INTRODUCTION

Enhanced recovery after cardiac surgery (ERACS) has been gaining rapid acceptance after multiple studies have demonstrated promising results in improved outcomes of enhanced recovery after surgery in other surgical fields (eg, colorectal, orthopedic, thoracic, etc). Cardiac surgery has several unique challenges, including sternotomy, cardiopulmonary bypass and associated coagulopathy, blood transfusion, and postoperative intensive care requirement. Nonetheless, selective cardiac surgical patients can still benefit from ERACS. Guidelines for perioperative care in cardiac surgery, previously published by the ERACS Society, are weighted heavily in preoperative and postoperative management without much focus on intraoperative care provided by anesthesiologists. To address this gap and to explore anesthesiology's contribution in achieving ERACS, the study authors' cardiac anesthesiology division, in collaboration with cardiac surgery, introduced the ERACS protocol in their institution in February 2020.

METHODS

The cardiac anesthesiology division, in collaboration with cardiac surgery, introduced the ERACS protocol consisting of multimodal opioid-sparing analgesia, including the introduction of regional blocks, hemostasis management protocol, reversal of neuromuscular blockade, and administration of antiemetics in the authors' institution in February 2020. They have conducted a retrospective chart review study comparing patients who have received ERACS measures with a similar historic cohort who underwent cardiac surgery prior to initiation of an ERACS protocol. The primary outcomes of the study were to determine patients' time to extubation, postoperative opioid consumption, intensive care unit (ICU) length of stay (LOS), and incidence of postoperative complications (eg, postoperative nausea vomiting [PONV], bleeding, ICU readmission, delirium.

RESULTS

The ERACS patients showed reduced opioid consumption (intraoperative fentanyl; postoperative fentanyl, as well as oxycodone, in the first 6 hours postoperatively), lesser mechanical ventilation (2.5 hours less), shorter ICU stays (5 hours less), shorter hospital LOS (1 day), and lesser incidence of PONV. None of the ERACS patients required blood transfusion. The study authors performed an anonymous survey among the anesthesiologists and ICU providers to assess providers' satisfaction, which showed 92% of survey takers agreed that the ERACS protocol should be continued for future cardiac patients, and 61% of survey takers reported superior pain control in ERACS group of patients while managing those patients.

DISCUSSION

The ERACS is achievable after the careful implementation of a series of measures. It does not signify only fast-track extubation and opioid-sparing analgesia, and must be implemented in the entire perioperative period beginning from preoperative clinic to postoperative rehabilitation. Cardiac anesthesiologists play a vital role in execution of intraoperative ERACS measures. Both providers and patients themselves are key stakeholders. A larger randomized prospective trial is warranted to solidify the inference.

Veno-arterial extracorporeal membrane oxygenation without allogeneic blood transfusion: An observational cohort study

INTRODUCTION

It remains unclear whether patients who will not accept allogeneic blood transfusion can be managed successfully with veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO). The objective of our study was to determine what percentage of V-A ECMO patients were managed without allogeneic blood transfusion.

METHODS

This was a retrospective, observational cohort study of patients with cardiogenic shock requiring V-A ECMO between January 2016 and January 2019. The primary outcome was avoidance of any allogeneic blood transfusion.

RESULTS

Of the 206 patients included, 23 (11.2%) were managed without any allogeneic blood transfusion. Fourteen (60.9%) avoided allogeneic blood transfusion during their entire hospitalization. "No-transfusion" patients were younger, more commonly men, were less likely to have a prior diagnosis of hypertension or coronary artery disease, had higher baseline hemoglobin, had higher SAVE scores, and were less likely to have received aspirin before ECMO. No patients in the "no-transfusion" group had major bleeding compared to 35% of patients in the blood transfusion group (p < 0.001). In-hospital mortality was 17.4% for those who avoided blood transfusion and 41.5% for those who received blood transfusion (p = 0.04). ECMO duration was significantly shorter in patients who avoided blood transfusion compared to those who received blood transfusion (median 3.5 vs 7 days, p < 0.001).

CONCLUSIONS

Select patients can be successfully managed on V-A ECMO without allogeneic blood transfusion. Jehovah's Witnesses and other patients with objections to allogeneic transfusion might be offered V-A ECMO if its anticipated duration is short (e.g. <7 days) and baseline hemoglobin concentration is high (e.g. ≥10 mg/dL).

Emergent Total Endovascular Arch Repair for Contained Aortic Arch Rupture: Another Tool in the Box

To date, emergent total endovascular aortic arch repair has not been described in the literature. We present a 67-year-old female with a poorly differentiated posterior mediastinal sarcoma. Imaging obtained was concerning for intravascular extension of the tumor into the thoracic aorta. While awaiting radiation therapy, the patient complained of worsening chest and arm pain, vital signs demonstrating tachypnea and hypoxia. Subsequent imaging revealed an increase in vascular erosion, concerning for a contained rupture, with complete obliteration of the left mainstem bronchus. The patient was emergently taken for percutaneous endovascular repair of her aortic arch. A three-vessel physician modified fenestrated graft was created and deployed with concurrent stenting of the innominate, left carotid, and left subclavian arteries. Interval computed tomography angiography revealed patency in all stented vessels, with no endoleak and no evidence of pseudoaneurysm. The patient was able to undergo chemotherapy with favorable decrease in tumor burden. Total endovascular aortic arch repair, when planned carefully, is an attractive option in high-risk patients who are otherwise not ideally suited for open total arch replacement.

The Caged Knickerbocker: A Novel Modification to Targeted False Lumen Management in Complex Aortic Dissection

INTRODUCTION

Targeted false lumen management has been described for complex presentations of aortic dissection. The "Knickerbocker" technique is often referenced and includes dilating a focal portion of an oversized endograft in the true lumen to purposefully rupture the false lumen septum, but at the expense of increased risk for visceral propagation and malperfusion. This case series describes a novel modification of the Knickerbocker technique by caging the distal end of the endograft prior to focal dilation.

METHODS

A retrospective chart review was conducted at a tertiary academic center from 2018-2020. Patients were included if they had a history or current presentation of aortic dissection and underwent a Caged Knickerbocker (CKB) repair. Data were collected to include demographics, indications for repair, technical success, perioperative outcomes, hospital course, mortality, and further aortic interventions.

RESULTS

Five patients were included in our evaluation. Four patients (80%) presented with chronic Type B aortic dissection (cTBAD) and concomitant aneurysmal degeneration of the thoracic aorta; 1 patient (20%) presented with an acute rupture secondary to cTBAD. Three patients (60%) had previous aortic repairs, 2 of which were for Type A Aortic Dissection that additionally required redo sternotomy and total arch replacement prior to CKB. CKB was technically successful in all cases with no peri-operative complications. Two (40%) patients required further aortic intervention due to aneurysmal degeneration.

CONCLUSION

Achieving complete false lumen thrombosis is a considerable challenge when managing complex aortic dissections. Our data demonstrate the technical feasibly and early successful outcomes with the CKB approach. Importantly, CKB facilitates future distal extension into the para-visceral aorta in cases of complex thoracoabdominal aortic aneurysms. Further research should focus on discerning individual patients who will benefit from targeted false lumen management and compare outcomes between different approaches.

Evaluating the Safety of Transcarotid Artery Revascularization under Local Anesthesia Prior to Coronary Artery Bypass Grafting Surgery

BACKGROUND

Controversy exists regarding the timing of intervention for patients with critical coronary artery disease (CAD) awaiting coronary artery bypass and severe carotid artery stenosis (CAS). Transcarotid artery revascularization (TCAR) is a minimally invasive revascularization alternative through direct transcervical carotid access that minimizes the chance of arch manipulation and consequent antegrade embolic stroke rate. While the TCAR procedure can be performed under local anesthesia (monitored anesthesia care [MAC]) versus general anesthesia, the hemodynamic benefits of local anesthesia in patients with severe CAD are significant. Patients receiving staged TCAR-coronary artery bypass grafting (CABG) have high-risk cardiovascular disease and require accurate perioperative neurological and hemodynamic evaluation that can be safely provided with local anesthesia.

METHODS

In this retrospective single-center study, 14 patients were systematically identified to have undergone staged TCAR prior to CABG surgery from December 2018 to October 2021. All patients underwent TCAR with local anesthesia and minimal sedation. Relevant patient demographics, medical and surgical history, preoperative covariates, and type of anesthesia administered were obtained from patients' charts. CAD was confirmed by either carotid duplex imaging or computed tomography angiography (CTA) of the head/neck.

RESULTS

Staged TCAR-CABG interventions were performed on 14 patients (64% male; mean age 65.0 years). No major adverse cardiac events were reported including transient ischemic attack (TIA), stroke, myocardial infarction (MI), or TCAR-related death in the interval between their TCAR and CABG as well as in a 12-month follow-up period. One patient required to return to the operating room (OR) for evacuation of a neck hematoma.

CONCLUSIONS

This study demonstrated high success rate of TCAR under local anesthesia prior to CABG (100%) with no incidence of perioperative stroke, MI, or death at 1-month, 6-month, and 12-month follow-up intervals. The authors support the use of staged TCAR-CABG with local anesthesia as a safe and promising treatment option for patients with high-grade cardiac disease, high risk of stroke, or multiple comorbidities that preclude a carotid endarterectomy (CEA).

Impact of Preoperative Hematocrit, Body Mass Index, and Red Cell Mass on Allogeneic Blood Product Usage in Adult Cardiac Surgical Patients: Report From a Statewide Quality Initiative

OBJECTIVE

The study aims were to evaluate current blood transfusion practice in cardiac surgical patients and to explore associations between preoperative anemia, body mass index (BMI), red blood cell (RBC) mass, and allogeneic transfusion.

DESIGN

Multicenter retrospective study.

SETTING

Academic and non-academic centers.

PARTICIPANTS AND INTERVENTIONS

After Institutional Review Board approval, 26,499 patients who underwent coronary artery bypass grafting ± valve replacement/repair between 2011 and 2019 were included from the Maryland Cardiac Surgery Quality Initiative database. Patients were stratified into BMI categories (<25, 25 to <30, and ≥30 kg/m²), and a multivariable logistic regression model was fit to determine if preoperative hematocrit, BMI, and RBC mass were associated independently with allogeneic transfusion.

RESULTS

Preoperative anemia was found in 55.4%, and any transfusion was administered to 49.3% of the entire cohort. Females and older patients had lower BMI and RBC mass. Increased RBC and cryoprecipitate transfusions occurred more frequently after surgery in the lower BMI group. After adjustments, increased transfusion was associated with a BMI <25 relative to a BMI ≥30 at an odds ratio (OR) of 1.26 (95% confidence interval [CI]: 1.08-1.39). For each 1% increase in preoperative hematocrit, transfusion was decreased by 9% (OR: 0.91; 95% CI: 0.90-0.92). For every 500 mL increase in RBC mass, there was a 43% reduction of transfusion (OR: 0.57; 95% CI: 0.55-0.58).

CONCLUSIONS

Transfusion probability modeling based on calculated RBC mass eliminated sex differences in transfusion risk based on preoperative hematocrit, and may better delineate which patients may benefit from more rigorous perioperative blood conservation strategy.

Spinal Cord Infarction With Prolonged Femoral Venoarterial Extracorporeal Membrane Oxygenation

OBJECTIVES

There have been sporadic reports of ischemic spinal cord injury (SCI) during venoarterial extracorporeal membrane oxygenation (VA-ECMO) support. The authors observed a troubling pattern of this catastrophic complication and evaluated the potential mechanisms of SCI related to ECMO.

DESIGN

This study was a case series.

SETTING

This study was performed at a single institution in a University setting.

PARTICIPANTS

Patients requiring prolonged VA-ECMO were included.

INTERVENTIONS

No interventions were done. This was an observational study.

MEASUREMENTS AND MAIN RESULTS

Four hypotheses of etiology were considered: (1) hypercoagulable state/thromboembolism, (2) regional hypoxia/hypocarbia, (3) hyperperfusion and spinal cord edema, and (4) mechanical coverage of spinal arteries. The SCI involved the lower thoracic (T7-T12 level) spinal cord to the cauda equina in all patients. Seven out of 132 (5.3%) patients with prolonged VA-ECMO support developed SCI. The median time from ECMO cannulation to SCI was 7 (range: 6-17) days.There was no evidence of embolic SCI or extended regional hypoxia or hypocarbia. A unilateral, internal iliac artery was covered by the arterial cannula in 6/7 86%) patients, but flow into the internal iliac was demonstrated on imaging in all available patients. The median total flow (ECMO + intrinsic cardiac output) was 8.5 L/min (LPM), and indexed flow was 4.1 LPM/m². The median central venous oxygen saturation was 88%, and intracranial pressure was measured at 30 mmHg in one patient, suggestive of hyperperfusion and spinal cord edema.

CONCLUSIONS

An SCI is a serious complication of extended peripheral VA-ECMO support. Its etiology remains uncertain, but the authors' preliminary data suggested that spinal cord edema from hyperperfusion or venous congestion could contribute.

PD-1 AND TIM-3 BLOCKING CANNOT ENHANCE APOPTOSIS OF CHRONIC LYMPHOCYTIC LEUKEMIA CELLS INDUCED BY PERIPHERAL BLOOD CD8+ T CELLS

AIM

Given the invaluable success of immune checkpoint inhibitors for tumor immunotherapy, in this study, the effect of programmed cell death 1 (PD-1) and T cell immunoglobulin-3 (TIM-3) blocking was investigated to induce apoptosis of leukemic cells by exhausted CD8⁺ T cells in patients with chronic lymphocytic leukemia (CLL).

MATERIALS AND METHODS

Peripheral blood CD8⁺ T cells were positively isolated from 16 CLL patients using magnetic beads separation method. Isolated CD8⁺ T cells were treated with either blocking anti-PD-1, anti-TIM-3 and isotype-matched control antibodies and then co-cultured with CLL leukemic cells as target. The percentage of apoptotic leukemic cells and the expression of apoptosis-related genes were evaluated by flow cytometry and real-time polymerase chain reaction methods, respectively. Interferon gamma and tumor necrosis factor alpha concentration was also measured by ELISA.

RESULTS

Flow cytometric analysis of apoptotic leukemic cells indicated that the blockade of PD-1 and TIM-3 did not significantly enhance the apoptosis of CLL cells by CD8+ T cells, which then were confirmed by analysis of BAX, BCL2 and CASP3 gene expression, which was similar in blocked and control groups. No significant difference was found between blocked and control groups in terms of interferon gamma and tumor necrosis factor alpha production by CD8+ T cells.

CONCLUSION

We concluded that the blockade of PD-1 and TIM-3 is not an effective strategy to restore the function of CD8+ T cells in CLL patients at the early clinical stages of the disease. Further in vitro and in vivo studies are needed to more address the application of immune checkpoint blockade in CLL patients.

Red Blood Cell Transfusion and Postoperative Infection in Patients Having Coronary Artery Bypass Grafting Surgery: An Analysis of the Society of Thoracic Surgeons Adult Cardiac Surgery Database

BACKGROUND

Coronary artery bypass grafting (CABG) is the most common cardiac surgical procedure in the world and up to one-third of patients are transfused red blood cells (RBCs). RBC transfusion may increase the risk for health care-associated infection (HAI) after CABG, but previous studies have shown conflicting results and many did not establish exposure temporality. Our objective was to explore whether intraoperative RBC transfusion is associated with increased odds of postoperative HAI. We hypothesized that intraoperative RBC transfusion would be associated with increased odds of postoperative HAI.

METHODS

We performed an observational cohort study of isolated CABG patients in the Society of Thoracic Surgeons adult cardiac surgery database from July 1, 2017, to June 30, 2019. The exposure was intraoperative RBC transfusion modeled as 0, 1, 2, 3, or 4+ units. The authors focused on intraoperative RBC transfusion as a risk factor, because it has a definite temporal relationship before postoperative HAI. The study's primary outcome was a composite HAI variable that included sepsis, pneumonia, and surgical site infection (both deep and superficial). Mixed-effects modeling, which controlled for hospital as a clustering variable, was used to explore the relationship between intraoperative RBC transfusion and postoperative HAI.

RESULTS

Among 362,954 CABG patients from 1076 hospitals included in our analysis, 59,578 patients (16.4%) received intraoperative RBCs and 116,186 (32.0%) received either intraoperative or postoperative RBCs. Risk-adjusted odds ratios for HAI in patients who received 1, 2, 3, and 4+ intraoperative RBCs were 1.11 (95% confidence interval [CI], 1.03-1.20; P = .005), 1.13 (95% CI, 1.05-1.21; P = .001), 1.15 (95% CI, 1.04-1.27; P = .008), and 1.14 (95% CI, 1.02-1.27; P = .02) compared to patients who received no RBCs.

CONCLUSIONS

Intraoperative RBC transfusion is associated with a small increase in odds of HAI in CABG patients. Future studies should explore whether reductions in RBC transfusion can also reduce HAIs.

Optimal reperfusion strategy in acute high-risk pulmonary embolism requiring extracorporeal membrane oxygenation support: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

The optimal pulmonary revascularization strategy in high-risk pulmonary embolism (PE) requiring implantation of extra corporeal membrane oxygenation (ECMO) remains controversial. We conducted a systematic review and meta-analysis of evidence comparing mechanical embolectomy and other strategies, including systemic, catheter-directed thrombolysis, or ECMO as stand-alone therapy, with regard to mortality and bleeding outcomes.

METHODS AND RESULTS

We identified 835 studies, 17 of which were included, comprising 327 PE patients. Overall, 32.4% were treated with mechanical pulmonary reperfusion, (of whom 85.9% had surgical embolectomy), while 67.61% received other strategies. The mortality rate was 26.4% in the mechanical reperfusion group, and 42.8% in the other strategy group. The pooled OR for mortality with mechanical reperfusion was 0.43 (95%CI, 0.23-0.997); p=0.009; I ²=35.2%) versus other reperfusion strategies; and 0.36 (95% CI, 0.18-0.73; p=0.009; I ² =32.9%) for surgical embolectomy versus thrombolysis. The rate of bleeding in patients under ECMO was 24.5% in the mechanical reperfusion group and 19.6% in the other reperfusion group (OR, 1.26; 95% CI, 0.54-2.92; I ², 7.7%). The meta-regression model did not identify any relationship between the covariates "more than one pulmonary reperfusion therapy", "ECMO implantation before pulmonary reperfusion therapy", clinical presentation of PE, or cancer-associated PE, and the associated outcomes.

CONCLUSIONS

The results of the present meta-analysis and meta-regression suggest that mechanical reperfusion, notably by surgical embolectomy, may yield favorable results regardless of the timing of ECMO implantation in the reperfusion timeline, independent of thrombolysis administration or cardiac arrest presentation.

The learning curve of robotic coronary arterial bypass surgery: A report from the STS database

BACKGROUND

There is limited data to inform minimum case requirements for training in robotically assisted coronary artery bypass grafting (RA-CABG). Current recommendations rely on nonclinical endpoints and expert opinion.

OBJECTIVES

To determine the minimum number of RA-CABG procedures required to achieve stable clinical outcomes.

METHODS

We included isolated RA-CABG in the Society of Thoracic Surgeons (STS) registry performed between 2014 and 2019 by surgeons without prior RA-CABG experience. Outcomes were approach conversion, reoperation, major morbidity or mortality, and procedural success. Case sequence number was used as a continuous variable in logistic regression with restricted cubic splines with fixed effects. Outcomes were compared between operations performed earlier versus later in case sequences using unadjusted and adjusted metrics.

RESULTS

There were 1195 cases performed by 114 surgeons. A visual inflection point occurs by a surgeon's 10th procedure for approach conversion, major morbidity or mortality, and overall procedural success after which outcomes stabilize. There was a significant decrease in the rate of approach conversion (7.7% and 2.5%), reoperation (18.9% and 10.8%), and major morbidity or mortality (21.7% and 12.9%), as well as an increase in the rate of procedural success (72.9% and 85.3%) with increasing experience between groups. In a multivariable logistic regression model, case sequences of >10 were an independent predictor of decreased approach conversion (odds ratio [OR]: 0.27; 95% confidence interval [CI]: 0.09-0.84) and increased rate procedural success (OR: 1.96; 95% CI: 1.00-3.84).

CONCLUSIONS

The learning curve for RA-CABG is initially steep, but stable clinical outcomes are achieved after the 10th procedure.

Mitral Valve Translocation: A Novel Operation for the Treatment of Secondary Mitral Regurgitation

BACKGROUND

Conventional annuloplasty repair of secondary (functional) ischemic mitral regurgitation (IMR) is associated with a 60% recurrence of moderate or greater mitral regurgitation at 2 years. We developed a novel repair technique for IMR that addresses the underlying geometric alterations of the mitral valve apparatus and compared outcomes with those of conventional repair in a swine model.

METHODS

Chronic IMR was induced by percutaneous embolization of the circumflex artery. Swine with severe IMR (median 9 weeks after infarction) underwent undersized rigid annuloplasty (n = 5) or translocation repair (n = 6). Translocation repair consisted of detaching the mitral valve en bloc at the annulus, creating a 1 cm wide frustum-shaped pericardial patch, and suturing the outer circumference of the patch to the annulus and inner circumference to the mitral valve.

RESULTS

Operative survival was 92% (11 of 12). All animals had none/trace residual central mitral regurgitation, and mean inflow gradients were similar (1 mm Hg [interquartile range, 1 to 2] vs 2 mm Hg [interquartile range, 1 to 2]; P = .75) in the annuloplasty and translocation groups, respectively. Median coaptation length marginally improved in conventional swine (3 to 4 mm, P = .05), but dramatically improved in translocation swine (3 to 8 mm, P = .003). Posterior leaflet angle increased from 39 to 80 degrees (P = .05) in annuloplasty swine but decreased from 50 to 31 degrees (P = .03) in translocation swine. The posterior leaflet was immobile after annuloplasty but had preserved motion after translocation (excursion, 1 degree vs 24 degrees; P = .045).

CONCLUSIONS

Mitral valve translocation effectively treats mitral regurgitation by relieving leaflet tethering. Compared with annuloplasty, mitral valve translocation creates a larger surface of coaptation and preserves leaflet mobility without compromising diastolic function.

A Novel Quantitative Ex Vivo Model of Functional Mitral Regurgitation

OBJECTIVE

Durability of mitral valve (MV) repair for functional mitral regurgitation (FMR) remains suboptimal. We sought to create a highly reproducible, quantitative ex vivo model of FMR that functions as a platform to test novel repair techniques.

METHODS

Fresh swine hearts (n = 10) were pressurized with air to a left ventricular pressure of 120 mmHg. The left atrium was excised and the altered geometry of FMR was created by radially dilating the annulus and displacing the papillary muscle tips apically and radially in a calibrated fashion. This was continued in a graduated fashion until coaptation was exhausted. Imaging of the MV was performed with a 3-dimensional (3D) structured-light scanner, which records 3D structure, texture, and color. The model was validated using transesophageal echocardiography in patients with normal MVs and severe FMR.

RESULTS

Compared to controls, the anteroposterior diameter in the FMR state increased 32% and the annular area increased 35% (P < 0.001). While the anterior annular circumference remained fixed, the posterior circumference increased by 20% (P = 0.026). The annulus became more planar and the tenting height increased 56% (9 to 14 mm, P < 0.001). The median coaptation depth significantly decreased (anterior leaflet: 5 vs 2 mm; posterior leaflet: 7 vs 3 mm, P < 0.001). The ex vivo normal and FMR models had similar characteristics as clinical controls and patients with severe FMR.

CONCLUSIONS

This novel quantitative ex vivo model provides a simple, reproducible, and inexpensive benchtop representation of FMR that mimics the systolic valvular changes of patients with FMR.

Peripheral cannulation for extracorporeal membrane oxygenation yields superior neurologic outcomes in adult patients who experienced cardiac arrest following cardiac surgery

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest has improved mortality in post-cardiac surgery patients; however, loss of neurologic function remains one of the main and devastating complications. We reviewed our experience with ECPR and investigated the effect of cannulation strategy on neurologic outcome in adult patients who experienced cardiac arrest following cardiac surgery that was managed with ECPR.

METHODS

Patients were categorized by central versus percutaneous peripheral VA-extracorporeal membrane oxygenation (ECMO) cannulation strategy. We reviewed patient records and evaluated in-hospital mortality, cause of death, and neurologic status 72 hours after cannulation.

RESULTS

From January 2010 to September 2019, 44 patients underwent post-cardiac surgery ECPR for cardiac arrest. Twenty-six patients received central cannulation; 18 patients received peripheral cannulation. Mean post-operative day of the cardiac arrest was 3 and 9 days (p = 0.006), and mean time between initiation of CPR and ECMO was 40 ± 24 and 28 ± 22 minutes for central and peripheral cannulation, respectively. After 72 hours of VA-ECMO support, 30% of centrally cannulated patients versus 72% of peripherally cannulated patients attained cerebral performance status 1-2 (p = 0.01). Anoxic brain injury was the cause of death in 26.9% of centrally cannulated and 11.1% of peripherally cannulated patients. Survival to discharge was 31% and 39% for central and peripheral cannulation, respectively.

CONCLUSIONS

Peripheral VA-ECMO allows for continuous CPR and systemic perfusion while obtaining vascular access. Compared to central cannulation, a peripheral cannulation strategy is associated with improved neurologic outcomes and decreased likelihood of anoxic brain death.

Anesthetic Considerations in Endovascular Repair of the Ascending Aorta

Since the first endovascular aortic repair in 1990, endovascular devices and the indications for their use have significantly grown. Considerable progress has been made in endovascular devices and techniques, such that endovascular repair is now considered first-line treatment for patients with descending aortic disease. However, for patients with ascending aortic disease, open surgical repair with cardiopulmonary bypass and hypothermic cardiac arrest was the only option until recently. Although the outcomes for open surgical repair of the ascending aorta have improved over the years, approximately 30% of patients with an emergent surgical indication, such as type A aortic dissection, are considered to be too high risk for open repair. For these patients, endovascular repair of the ascending aorta offers a life-saving procedure. The ascending aorta is regarded as the final frontier for endovascular therapy. Endovascular repair of it has posed a formidable challenge thus far, due to its unique anatomy, hemodynamic forces, and lack of an appropriate stent-graft designed specifically for the ascending aorta. Although currently there are no comprehensive data from randomized clinical trials, there are several case series and case reports that have shown favorable outcomes. Improvements in available devices soon will drive an exponential increase in the number of patients undergoing endovascular ascending aortic repair. In this review, the authors discuss multiple aspects of endovascular ascending aortic repair including the unique surgical and anesthetic considerations, the devices used, and the available outcomes data, and future directions are also explored.

A Dedicated Veno-Venous Extracorporeal Membrane Oxygenation Unit during a Respiratory Pandemic: Lessons Learned from COVID-19 Part II: Clinical Management

(1) Background: COVID-19 acute respiratory distress syndrome (CARDS) has several distinctions from traditional acute respiratory distress syndrome (ARDS); however, patients with refractory respiratory failure may still benefit from veno-venous extracorporeal membrane oxygenation (VV-ECMO) support. We report our challenges caring for CARDS patients on VV-ECMO and alterations to traditional management strategies. (2) Methods: We conducted a retrospective review of our institutional strategies for managing patients with COVID-19 who required VV-ECMO in a dedicated airlock biocontainment unit (BCU), from March to June 2020. The data collected included the time course of admission, VV-ECMO run, ventilator length, hospital length of stay, and major events related to bleeding, such as pneumothorax and tracheostomy. The dispensation of sedation agents and trial therapies were obtained from institutional pharmacy tracking. A descriptive statistical analysis was performed. (3) Results: Forty COVID-19 patients on VV-ECMO were managed in the BCU during this period, from which 21 survived to discharge and 19 died. The criteria for ECMO initiation was altered for age, body mass index, and neurologic status/cardiac arrest. All cannulations were performed with a bedside ultrasound-guided percutaneous technique. Ventilator and ECMO management were routed in an ultra-lung protective approach, though varied based on clinical setting and provider experience. There was a high incidence of pneumothorax (n = 19). Thirty patients had bedside percutaneous tracheostomy, with more procedural-related bleeding complications than expected. A higher use of sedation was noted. The timing of decannulation was also altered, given the system constraints. A variety of trial therapies were utilized, and their effectiveness is yet to be determined. (4) Conclusions: Even in a high-volume ECMO center, there are challenges in caring for an expanded capacity of patients during a viral respiratory pandemic. Though institutional resources and expertise may vary, it is paramount to proceed with insightful planning, the recognition of challenges, and the dynamic application of lessons learned when facing a surge of critically ill patients.

A Dedicated Veno-Venous Extracorporeal Membrane Oxygenation Unit during a Respiratory Pandemic: Lessons Learned from COVID-19 Part I: System Planning and Care Teams

Background: The most critically ill patients with coronavirus disease 2019 (COVID-19) may require advanced support modalities, such as veno-venous extracorporeal membrane oxygenation (VV-ECMO). A systematic, methodical approach to a respiratory pandemic on a state and institutional level is critical. Methods: We conducted retrospective review of our institutional response to the COVID-19 pandemic, focusing on the creation of a dedicated airlock biocontainment unit (BCU) to treat patients with refractory COVID-19 acute respiratory distress syndrome (CARDS). Data were collected through conversations with staff on varying levels in the BCU, those leading the effort to make the BCU and hospital incident command system, email communications regarding logistic changes being implemented, and a review of COVID-19 patient census at our institution from March through June 2020. Results: Over 2100 patients were successfully admitted to system hospitals; 29% of these patients required critical care. The response to this respiratory pandemic augmented intensive care physician staffing, created a 70-member nursing team, and increased the extracorporeal membrane oxygenation (ECMO) capability by nearly 200%. During this time period, 40 COVID-19 patients on VV-ECMO were managed in the BCU. Challenges in an airlock unit included communication, scarcity of resources, double-bunking, and maintaining routine care. Conclusions: Preparing for a surge of critically ill patients during a pandemic can be a daunting task. The implementation of a coordinated, system-level approach can help with the allocation of resources as needed. Focusing on established strengths of hospitals within the system can guide triage based on individual patient needs. The management of ECMO patients is still a specialty care, and a systematic and hospital based approach requiring an ECMO team composed of multiple experienced individuals is paramount during a respiratory viral pandemic.

Bedside angiography of distal perfusion catheter for veno-arterial extracorporeal membrane oxygenation

BACKGROUND

The aim of this study was to evaluate the ipsilateral lower extremity (ILE) outcomes of patients who underwent bedside angiography via the distal perfusion catheter while on femoral veno-arterial extracorporeal membrane oxygenation (VA ECMO).

METHODS

This is a retrospective analysis of all patients placed on VA ECMO at a single center from January 2017 to December 2019 who underwent bedside angiography via the distal perfusion catheter.

RESULTS

Twenty-four patients underwent bedside angiography via the distal perfusion catheter after being placed on VA ECMO. A vasodilator was directly administered in three patients for suspected spasm. One patient had distal thrombus and underwent thrombectomy and fasciotomy. One patient had a dislodged catheter and underwent thrombectomy, fasciotomy, and replacement of the catheter. One patient had severe ILE ischemia, however was not intervened upon due to critical acuity. Finally, one patient had inadvertent placement in the saphenous vein and had a new catheter placed in the SFA. No patients underwent amputation. Ultimately, 21 patients (87.5%) had no ILE compromise at the end their ECMO course. Survival to decannulation was 66.7% (n = 16).

CONCLUSIONS

Bedside angiography of the distal perfusion catheter is feasible and can be a useful adjunct in informing the need for further intervention to the ILE.

CLASSIFICATIONS

extracorporeal membrane oxygenation, ischemia.

Corneal biomechanical properties after soft contact lens wear measured on a dynamic Scheimpflug analyzer: A before and after study

OBJECTIVES

To evaluate the corneal biomechanics before and after daily use of contact lenses (CLs), measured by Scheimpflug-based devices.

METHODS

This prospective clinical study includes participants who were scheduled to use CLs daily for refractive error. The biomechanical parameters were measured by the Corneal Visualization Scheimpflug Technology (Corvis ST) before and one month after using the soft CLs.

RESULTS

Twenty-three subjects (46 eyes), including 16 female (76.2%) with a mean age of 28±7.29 years, were enrolled. There was no significant difference among biomechanical factors measured before and after contact lens wear (P>0.05). Using regression analysis of the biomechanical markers, we found a statistically significant association between second applanation length (A2 length) (P=0.001), highest concavity radius (HCR) (P=0.05), deflection amplitude ratio (DA_ratio) (P=0.05) and integrated radius (P<0.001) with age. Regarding spherical equivalent, we found a statistically significant association between central corneal thickness (CCT) (P=0.05), A2 length (P=0.03) and stiffness parameter at first applanation (SPA₁) (P=0.02).

CONCLUSIONS

We did not find a significant difference in terms of corneal biomechanical parameters between baseline and month 1; but regression analyses showed a statistically significant association between A2 length, HCR, DA_ratio, integrated radius, CCT and SPA₁ and certain subject characteristics.

Complete percutaneous decannulation from femoral venoarterial extracorporeal membrane oxygenation

Objectives

To evaluate the clinical outcomes and perioperative complications associated with complete percutaneous decannulation of femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO) with the MANTA closure device.

Methods

This is a retrospective analysis of a single surgeon consecutive series of 14 patients at a single center who underwent decannulation from VA-ECMO, 10 of whom underwent a percutaneous method of femoral cannula removal.

Results

After a mean duration of VA-ECMO support of 7.4 ± 3.8 days, all 10 patients, with arterial cannulas ranging in size from 17 to 21 Fr, underwent percutaneous decannulation with the MANTA closure device, with immediate hemostasis. One patient had acute lower limb ischemia that was recognized intraoperatively and successfully treated with suction embolectomy. Two patients had a pseudoaneurysm at the distal perfusion catheter site recognized on perioperative imaging studies, one resolving with observation and the other necessitating thrombin injection. One patient had a hematoma that resolved with observation.

Conclusions

Percutaneous decannulation from VA-ECMO using the MANTA large-bore vascular closure device is feasible and results in immediate hemostasis with excellent angiographic results.

Clinical Practice Variation and Outcomes for Stanford Type A Aortic Dissection Repair Surgery in Maryland: Report from a Statewide Quality Initiative

Background  Stanford Type A aortic dissection repair surgery is associated with high mortality and clinical practice remains variable among hospitals. Few studies have examined statewide practice variation.

Methods  Patients who had Stanford Type A aortic dissection repair surgery in Maryland between July 1, 2014 and June 30, 2018 were identified using the Maryland Cardiac Surgery Quality Initiative (MCSQI) database. Patient demographics, comorbidities, surgery details, and outcomes were compared between hospitals. We also explored the impact of arterial cannulation site and brain protection technique on outcome.

Results  A total of 233 patients were included from eight hospitals during the study period. Seventy-six percent of surgeries were done in two high-volume hospitals (≥10 cases per year), while the remaining 24% were done in low-volume hospitals. Operative mortality was 12.0% and varied between 0 and 25.0% depending on the hospital. Variables that differed significantly between hospitals included patient age, the percentage of patients in shock, left ventricular ejection fraction, creatinine level, arterial cannulation site, brain protection technique, tobacco use, and intraoperative blood transfusion. The percentage of patients who underwent aortic valve repair or replacement procedures differed significantly between hospitals ( p  < 0.001), although the prevalence of moderate-to-severe aortic insufficiency was not significantly different ( p  = 0.14). There were no significant differences in clinical outcomes including mortality, renal failure, stroke, or gastrointestinal complications between hospitals or based on arterial cannulation site (all p  > 0.05). Patients who had aortic cross-clamping or endovascualr repair had more embolic strokes when compared with patients who had hypothermic circulatory arrest ( p  = 0.03).

Conclusion  There remains considerable practice variation in Stanford Type A aortic dissection repair surgery within Maryland including some modifiable factors such as intraoperative blood transfusion, arterial cannulation site, and brain protection technique. Continued efforts are needed within MCSQI and nationally to evaluate and employ the best practices for patients having acute aortic dissection repair surgery.

Type B Aortic Dissection Complicated by Intimo-Intimal Intussusception and Extensive Intimal Denuding: Case Report with Long-term Follow-up

BACKGROUND

Acute aortic dissection rarely results in circumferential dissections of the aortic intima that may lead to intimo-intimal intussusception (IIS) with complete separation from the aortic wall. Circumferential dissection may then result in distal embolization of the involved intima and media, adding considerable complexity to the management of such cases. Despite the severity of this complication, the natural history of aortic disease following extensive intimal denuding and IIS is not well documented in the literature. Here we present a case with long-term follow-up of type B aortic dissection (TBAD) complicated by IIS and embolization of the intima into the distal aorta following thoracic endovascular aortic repair.

METHODS

Medical records and imaging studies were retrospectively reviewed with the approval of the Institutional Review Board. A single patient underwent repair of a TBAD that was complicated by IIS, with follow-up for 6 years. Aortic recovery was monitored with serial computerized tomography scans.

RESULTS

During endovascular stent deployment, the patient's dissection progressed circumferentially, leading to distal embolization of the intima and aortic occlusion. An open transabdominal aortic exploration was performed to extract the embolized intima. Despite this severe aortic structural disruption, the patient recovered well postoperatively and exhibited favorable aortic remodeling over long-term follow-up. The denuded aorta did not rupture or develop progressive worsening aneurysmal dilation and the diameter of the involved aortic segment remained stable during follow-up.

CONCLUSIONS

Acute TBADs can progress to circumferential intimal separation and IIS when managed with endovascular stenting and balloon dilation. Continued endovascular management once IIS has occurred may lead to further intimal damage, resulting in distal embolization of the intima and aortic occlusion. Thus, IIS may require conversion to open repair. However, in the event that loss of the aortic intima does occur following IIS, it is possible for the denuded aorta to recover well and remain stable with favorable remodeling over long-term follow-up.

Neomedia Aortic Root Repair for Type A Aortic Dissection Despite Anomalous Right Coronary Artery

An anomalous right coronary artery arising from the left coronary sinus is a rare anatomic variant. Here we report a patient who presented with an acute type A dissection and underwent successful aortic root reconstruction with resuspension of the aortic valve and neomedia creation in the presence of an anomalous right coronary artery with a good clinical outcome.

Racial Disparity in Cardiac Surgery Risk and Outcome: Report From a Statewide Quality Initiative

BACKGROUND

Racial disparities persist in health care. Our study objective was to evaluate racial disparity in cardiac surgery in Maryland.

METHODS

A statewide database was used to identify patients. Demographics, comorbidities, and predicted risk of death were compared between races. Crude mortality and incidence of complications were compared between groups, as were risk-adjusted odds for mortality and major morbidity or mortality.

RESULTS

The study included 23,094 patients. Most patients were white (75.8%), followed by African American (16.3%), Asian (3.8%), and other races (4.1%). African Americans had a higher preoperative risk for mortality based on The Society of Thoracic Surgeons predictive models compared with white patients (3.0% vs 2.3%, P < .001). African Americans also had higher prevalence of diabetes mellitus, hypertension, peripheral vascular disease, and cerebral vascular disease than white patients. After adjustment for preoperative risk, there was no difference in 30-day mortality between African Americans (odds ratio [OR], 1.26; 95% confidence interval [CI], 0.99-1.59), Asians (OR, 1.22; 95% CI, 0.75-1.97), and other races (OR, 1.18; 95% CI, 0.74-1.89) compared with whites. African Americans had lower risk-adjusted odds of major morbidity or mortality compared with whites (OR, 0.83; 95% CI, 0.75-0.93).

CONCLUSIONS

African American cardiac surgical patients have the highest preoperative risk in Maryland. Patients appeared to receive excellent cardiac surgical care, regardless of race, as risk-adjusted mortality did not differ between groups, and African American patients had lower risk-adjusted odds of major morbidity or mortality than white patients. Future interventions in Maryland should be aimed at reducing preoperative risk disparity in cardiac surgical patients.

Degenerative Mitral Valve Repair Simplified: An Evolution to Universal Artificial Cordal Repair

BACKGROUND

Resectional and artificial cordal repair techniques are effective strategies for degenerative mitral valve (MV) repair. However, resectional repair requires a tailored approach using various techniques, whereas cordal repair offers a simpler, easily reproducible repair. The approach described in this study approach has evolved from resectional to cordal over time, and outcomes are compared between the eras.

METHODS

Clinical and echocardiographic outcomes of all patients undergoing MV repair for degenerative mitral regurgitation (MR) from January 2004 to September 2017 were reviewed. Patients were stratified by era: from January 2004 to June 2011 (era 1; n = 405), resectional techniques were used in 62% and artificial cordal techniques were used in 38%. From July 2011 to September 2017 (era 2; n = 438), artificial cordal repair was used in 98% of patients. The primary outcome was repair failure, defined as greater than moderate MR or MV reoperation.

RESULTS

Of 847 patients with degenerative MR, successful repair was achieved in 843 patients (99.5% repair rate). Leaflet prolapse was posterior in 66%, anterior in 8%, and bileaflet in 26%. Cardiopulmonary bypass time and cross-clamp times were shorter in era 2 (CPB: 109 [IQR, 92-128] minutes vs 97 [IQR, 76-121] minutes; P < .001; cross-clamp: 88 [IQR, 73-106] minutes vs. 79 [IQR, 61-99] minutes; P < .001). Predismissal echocardiography demonstrated no MR or trace MR in 95%, mild MR in 4.7%, and moderate MR in 0.3% of patients. Operative mortality was similar in the eras (0.5% vs 0.5%; P > .999). The rates of 5-year freedom from repair failure (95.1% vs 95.5%; P = .707), stroke (96.8% vs 95.3%; P = .538), and endocarditis (99.3% vs 99.7%; P = .604) were similar between the eras.

CONCLUSIONS

Artificial cordal repair for all patients with degenerative MR simplifies MV repair and yields equivalent, excellent outcomes compared with a tailored resectional approach.

Factors associated with acute stroke after type A aortic dissection repair: An analysis of the Society of Thoracic Surgeons National Adult Cardiac Surgery Database

OBJECTIVES

Data from the Society of Thoracic Surgeons Adult Cardiac Surgery Database was used to examine the incidence and factors associated with acute stroke following type A repair.

METHODS

Acute type A aortic dissection repairs performed from 2014 to 2017 were identified from the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The effect of cannulation strategy (eg, axillary, femoral, direct, or innominate), lowest temperature, cerebral protection techniques (antegrade cerebral profusion, retrograde cerebral perfusion, both, or none), repair technique, and institutional volume on postoperative stroke was investigated.

RESULTS

Acute type A repair was performed on 8937 patients at 772 centers, of which 7353 met inclusion criteria. Operative mortality was 17% and incidence of postoperative stroke was 13%. Axillary cannulation was associated with lower risk of stroke versus femoral (odds ratio, 0.60; P < .001). Retrograde cerebral perfusion was associated with reduced risk for stroke compared with no cerebral perfusion (odds ratio, 0.75; P = .008) or antegrade cerebral perfusion (odds ratio, 0.75; P = .007). Total arch replacement was associated with greater risk for stroke versus hemiarch technique (odds ratio, 1.30; P = .013). Longer circulatory arrest time, cerebral perfusion time, and cardiopulmonary bypass time were all related to higher risk of postoperative stroke.

CONCLUSIONS

Stroke is a common complication after type A repair. Axillary cannulation was associated with lower incidence of stroke, whereas femoral cannulation significantly increased the risk of stroke regardless of the cerebral perfusion strategy or the degree of hypothermia. Retrograde cerebral profusion was found to have reduced risk for postoperative stroke. Degree of hypothermia and center volume were not related to stroke incidence.

Programmatic and Surgeon Specialization Improves Mortality in Isolated Coronary Bypass Grafting

BACKGROUND

Throughout surgery, specialization in a procedure has been shown to improve outcomes. Currently, there is no evidence for or against subspecialization in coronary surgery. Tasked with the goal of improving outcomes after isolated coronary artery bypass grafting (CABG), our institution sought to determine whether the development of a subspecialized coronary surgery program would improve morbidity and mortality.

METHODS

All isolated CABG operations at a single institution were retrospectively examined in two distinct periods, 2002 to 2013 and 2013 to 2016, before and after the implementation of a subspecialized coronary surgery program. Improved policies included leadership and subspecialization of a program director, standardization of surgical technique and postoperative care, and monthly multidisciplinary quality review. Outcomes were collected and compared.

RESULTS

Between 2002 and 2013, 3,256 CABG operations were done by 16 surgeons, the most frequent surgeon doing 33%. Between 2013 and 2016, 1,283 operations were done by 10 surgeons, 70% by the coronary program director. CABGs done in the specialized era had shorter bypass and clamps times and increased use of bilateral internal mammary arteries. Blood transfusion and complication rates, including permanent stroke and prolonged ventilation, were significantly decreased after implementation of the coronary program. Likewise, overall operative mortality (2.67% vs 1.48%, p = 0.02) was significantly reduced.

CONCLUSIONS

Subspecialization in CABG and dedicated coronary surgery programs may lead to faster operations, increased use of bilateral internal mammary arteries, fewer complications, and improved survival after isolated CABG.

Early Operation in Patients With Mitral Valve Infective Endocarditis and Acute Stroke Is Safe

BACKGROUND

To determine if preoperative embolic stroke is associated with an increased risk of postoperative stroke among patients undergoing early operation for mitral valve (MV) infective endocarditis (IE), we compared outcomes among patients presenting with and without acute stroke.

METHODS

From 2003 to 2015, 243 consecutive patients underwent surgery for active MV IE. Patients were categorized into 2 groups: 72% (174 of 243 patients) with no preoperative acute stroke (clinical, radiographic or both) and 28% (69 of 243 patients) with stroke. Both preoperative and postoperative strokes were confirmed in all patients with brain computed tomography or magnetic resonance imaging and comprehensive examination by a neurologist.

RESULTS

Among patients presenting with stroke, 33% (23 of 69 patients) were asymptomatic and had only positive imaging findings. The median time from admission to operation was 5 days. The overall rate of new postoperative stroke was 4% (10 of 243 patients). The rate of postoperative stroke was not different between the 2 groups: 4% (7 of 174 patients) among patients with no preoperative stroke and 4% (3 of 69 patients) with stroke (p = 0.9). One patient developed a hemorrhagic conversion of an acute infarct. Operative mortality was 7% (13 of 174 patients) among patients with no preoperative stroke and 7% (5 of 69 patients) among patients with stroke (p = 0.9).

CONCLUSIONS

MV surgery for IE and acute stroke can be performed early with a low risk of postoperative neurologic complications. When indicated, surgical intervention for MV IE complicated by acute stroke should not be delayed.

Bilateral Internal Mammary Artery Use Can Be Safely Taught Without Increasing Morbidity or Mortality

BACKGROUND

Evidence shows a likely survival benefit with the use of bilateral internal mammary arteries (BIMA) compared with a single internal mammary artery (SIMA). Nonetheless, BIMA use is often not used or taught because of a perceived increase in operative time and complexity. This study aimed to evaluate operative time, morbidity, and mortality in both resident and nonresident cases using BIMA compared with SIMA.

METHODS

Consecutive patients undergoing isolated coronary artery bypass grafting (October 2012 to April 2015) at a single institution were reviewed. Cases were stratified on the basis of the use of SIMA versus BIMA and resident teaching versus nonresident teaching cases. Primary outcomes included operative time, postoperative morbidity, and mortality.

RESULTS

A total of 416 patients were identified; 335 of 416 (81%) patients received a SIMA, and 81 of 416 (19%) patients received BIMA. A total of 184 of 416 (44%) were resident cases: 143 of the 335 (43%) SIMA cases and 41 of the 81 (51%) BIMA cases. Use of BIMA in resident cases was associated with a longer operative and cardiopulmonary bypass (CPB) time than resident SIMA cases, but this increased time did not affect morbidity or mortality. Use of SIMA versus BIMA in nonresident cases had no significant difference on total operative time, CPB time, postoperative morbidity, or mortality. Overall, operative and 1-year mortality rates were similar in the SIMA and BIMA groups (SIMA: 1.2%, 1.8%, respectively; BIMA: 0%, 0%, respectively; p = NS).

CONCLUSIONS

In the hands of an experienced surgeon, BIMA use can be effectively performed without an increase in operative or CPB time. In resident teaching cases, BIMA use may increase operative time, but it can be safely taught without affecting morbidity or mortality.