Novel Left Ventricular Unloading Strategies in Patients on Peripheral Venoarterial Extracorporeal Membrane Oxygenation Support.

The purpose of this study was to evaluate left ventricular (LV) unloading strategies in patients supported with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). A retrospective review was conducted of all consecutive patients requiring VA-ECMO support for any indication, who underwent novel LV unloading strategies with either direct left atrial venoarterial (LAVA) cannulation or pulmonary artery venoarterial (PAVA) venting, in comparison to Impella and intra-aortic balloon pump (IABP). The primary outcome was successful bridge to transplant, LV assist device, or myocardial recovery. Forty-six patients (63% male, mean age 52.8 ± 17.6 years) were included. Fourteen patients (30%) underwent novel unloading with either LAVA or PAVA, 11 patients (24%) underwent IABP placement, and 21 patients (46%) underwent Impella insertion. In the novel LV unloading cohort, 10 patients (71%) survived to hospital discharge. Four patients (29%) were weaned from ECMO and eight patients (57%) underwent cardiac transplantation. Although a trend favoring cannula-based unloading for the primary outcome was noted, the cohort was too small for statistical significance (79% LAVA/PAVA, 57% Impella, 45% IABP; p = 0.21). However, probability of survival was greater in the LAVA/PAVA cohort compared to Impella and IABP ( p < 0.05). Thus, we demonstrate the efficacy of LA and PA cannulation as an alternative LV unloading strategy for patients supported with peripheral VA-ECMO.

Deep Parasternal Intercostal Plane Block for Postoperative Analgesia After Sternotomy for Cardiac Surgery-A Retrospective Cohort Study.

OBJECTIVE: To examine the analgesic efficacy of postoperative deep parasternal intercostal plane (DPIP) blocks for patients having cardiac surgery via median sternotomy. DESIGN: This single-center retrospective study compared patients receiving bilateral DPIP blocks with a matched cohort of patients not receiving DPIP blocks. SETTING: Large quaternary referral center. PARTICIPANTS: Adult patients admitted to the authors' institution from January 1, 2016, to August 14, 2020, for elective cardiac surgery via median sternotomy. INTERVENTIONS: Patients received ultrasound-guided bilateral DPIP blocks. MEASUREMENTS AND MAIN RESULTS: A total of 113 patients received a DPIP block; 3,461 patients did not. The estimated multiplicative change in cumulative opioid consumption through 24 hours was 0.42 (95% CI 0.32-0.56; p < 0.001), indicating that patients receiving DPIP blocks required 60% fewer opioids than patients who did not. Proportional odds ratios for the average pain score on postoperative day (POD) 0 was 0.46 (95% CI 0.32-0.65; p < 0.001), and POD 1 was 0.67 (95% CI 0.47-0.94; p = 0.021), indicating lower pain scores for patients receiving blocks. The exploratory analysis identified an inverse correlation between DPIP blocks and atrial fibrillation incidence (2% v 15%; inverse probability of treatment weighting odds ratio 0.088, 95% CI 0.02-0.41; p = 0.002). CONCLUSIONS: The use of DPIP blocks in patients undergoing cardiac surgery via median sternotomy was associated with less opioid use and improved pain scores in the early postoperative period compared with patients not receiving blocks. Prospective randomized controlled studies should further elucidate the efficacy and risks of DPIP blocks in cardiac surgery.

Extracorporeal membrane oxygenation and acute kidney injury: a single-center retrospective cohort.

To assess the relationship between acute kidney injury (AKI) with outcomes among patients requiring extracorporeal membrane oxygenation (ECMO). This is a single-center, retrospective cohort study of adult patients admitted to intensive care units (ICU) at a tertiary referral hospital requiring ECMO from July 1, 2015, to August 30, 2019. We assessed the temporal relationship of AKI and renal replacement therapy with ECMO type (VV vs. VA). The primary outcome was in-hospital mortality rates. We used Kruskal-Wallis or chi-square tests for pairwise comparisons, cause-specific Cox proportional hazards models were utilized for the association between AKI prevalence and in-hospital mortality, and a time-dependent Cox model was used to describe the association between AKI incidence and mortality. After the screening, 190 patients met eligibility criteria [133 (70%) AKI, 81 (43%) required RRT]. The median age was 61 years, and 61% were males. Among AKI patients, 48 (36%) and 85 (64%) patients developed AKI before and after ECMO, respectively. The SOFA Day 1, baseline creatinine, respiratory rate (RR), use of vasopressin, vancomycin, proton pump inhibitor, antibiotics, duration of mechanical ventilation and ECMO, and ICU length of stay were higher in AKI patients compared with those without AKI (P < 0.01). While ICU and in-hospital mortality rates were 46% and 50%, respectively, there were no differences based on the AKI status. The type and characteristics of ECMO support were not associated with AKI risk. Among AKI patients, 77 (58%) were oliguric, and 46 (60%) of them received diuretics. Urine output in the diuretic group was only higher on the first day than in those who did not receive diuretics (P = 0.03). Among ECMO patients, AKI was not associated with increased mortality but was associated with prolonged duration of mechanical ventilation and ICU length of stay.

Percutaneous Mechanical Circulatory Support as a Bridge to Transplantation in Ebstein Anomaly.

Ebstein anomaly is a rare congenital heart defect occurring in 0.0005% of the population because of mispositioning and malformation of the tricuspid valve. Here, we present the first description and associated imaging of percutaneous mechanical circulatory support in the setting of cardiogenic shock secondary to Ebstein anomaly.

Exposure to Arterial Hyperoxia During Extracorporeal Membrane Oxygenator Support and Mortality in Patients With Cardiogenic Shock.

BACKGROUND: Exposure to hyperoxia, a high arterial partial pressure of oxygen (PaO2), may be associated with worse outcomes in patients receiving extracorporeal membrane oxygenator (ECMO) support. We examined hyperoxia in the Extracorporeal Life Support Organization Registry among patients receiving venoarterial ECMO for cardiogenic shock. METHODS: We included Extracorporeal Life Support Organization Registry patients from 2010 to 2020 who received venoarterial ECMO for cardiogenic shock, excluding extracorporeal CPR. Patients were grouped based on PaO2 after 24 hours of ECMO: normoxia (PaO2 60-150 mmHg), mild hyperoxia (PaO2 151-300 mmHg), and severe hyperoxia (PaO2 >300 mmHg). In-hospital mortality was evaluated using multivariable logistic regression. RESULTS: Among 9959 patients, 3005 (30.2%) patients had mild hyperoxia and 1972 (19.8%) had severe hyperoxia. In-hospital mortality increased across groups: normoxia, 47.8%; mild hyperoxia, 55.6% (adjusted odds ratio, 1.37 [95% CI, 1.23-1.53]; P<0.001); severe hyperoxia, 65.4% (adjusted odds ratio, 2.20 [95% CI, 1.92-2.52]; P<0.001). A higher PaO2 was incrementally associated with increased in-hospital mortality (adjusted odds ratio, 1.14 per 50 mmHg higher [95% CI, 1.12-1.16]; P<0.001). Patients with a higher PaO2 had increased in-hospital mortality in each subgroup and when stratified by ventilator settings, airway pressures, acid-base status, and other clinical variables. In the random forest model, PaO2 was the second strongest predictor of in-hospital mortality, after older age. CONCLUSIONS: Exposure to hyperoxia during venoarterial ECMO support for cardiogenic shock is strongly associated with increased in-hospital mortality, independent from hemodynamic and ventilatory status. Until clinical trial data are available, we suggest targeting a normal PaO2 and avoiding hyperoxia in CS patients receiving venoarterial ECMO.

Pectoral Fascial Plane Versus Paravertebral Blocks for Minimally Invasive Mitral Valve Surgery Analgesia.

OBJECTIVES: This study examined the postoperative analgesic efficacy of single-injection pectoral fascial plane (PECS) II blocks compared to paravertebral blocks for elective robotic mitral valve surgery. DESIGN: A single-center retrospective study that reported patient and procedural characteristics, postoperative pain scores, and postoperative opioid use for patients undergoing robotic mitral valve surgery. SETTING: This investigation was performed at a large quaternary referral center. PARTICIPANTS: Adult patients (age ≥18) admitted to the authors' hospital from January 1, 2016, to August 14, 2020, for elective robotic mitral valve repair who received either a paravertebral or PECS II block for postoperative analgesia. INTERVENTIONS: Patients received an ultrasound-guided, unilateral paravertebral or PECS II nerve block. MEASUREMENTS AND MAIN RESULTS: One hundred twenty-three patients received a PECS II block, and 190 patients received a paravertebral block during the study period. The primary outcome measures were average postoperative pain scores and cumulative opioid use. Secondary outcomes included hospital and intensive care unit lengths of stay, need for reoperation, need for antiemetics, surgical wound infection, and atrial fibrillation incidence. Patients receiving the PECS II block required significantly fewer opioids in the immediate postoperative period than the paravertebral block group, and had comparable postoperative pain scores. No increase in adverse outcomes was noted for either group. CONCLUSIONS: The PECS II block is a safe and highly effective option for regional analgesia for robotic mitral valve surgery, with demonstrated efficacy comparable to the paravertebral block.

Cardiogenic shock severity and mortality in patients receiving venoarterial extracorporeal membrane oxygenator support.

AIMS: Shock severity predicts mortality in patients with cardiogenic shock (CS). We evaluated the association between pre-cannulation Society for Cardiovascular Angiography and Intervention (SCAI) shock classification and mortality among patients receiving venoarterial (VA) extracorporeal membrane oxygenation (ECMO) support for CS. METHODS AND RESULTS: We included Extracorporeal Life Support Organization (ELSO) Registry patients from 2010 to 2020 who received VA ECMO for CS. SCAI shock stage was assigned based on hemodynamic support requirements prior to ECMO initiation. In-hospital mortality was analyzed using multivariable logistic regression. We included 12 106 unique VA ECMO patient runs with a median age of 57.9 (interquartile range: 46.8, 66.1) years and 31.8% were females; 3472 (28.7%) were post-cardiotomy. The distribution of SCAI shock stages at ECMO initiation was: B, 821 (6.8%); C, 7518 (62.1%); D, 2973 (24.6%); and E, 794 (6.6%). During the index hospitalization, 6681 (55.2%) patients died. In-hospital mortality increased incrementally with SCAI shock stage (adjusted OR: 1.24 per SCAI shock stage, 95% CI: 1.17-1.32, P < 0.001): B, 47.5%; C, 52.8%; D, 60.8%; E, 65.1%. A higher SCAI shock stage was associated with increased in-hospital mortality in key subgroups, although the SCAI shock classification was only predictive of mortality in non-surgical (medical) CS and not in post-cardiotomy CS. CONCLUSION: The severity of shock prior to cannulation is a strong predictor of in-hospital mortality in patients receiving VA ECMO for CS. Using the pre-cannulation SCAI shock classification as a risk stratification tool can help clinicians refine prognostication for ECMO recipients and guide future investigations to improve outcomes.

Cannulation strategies for acute type A dissection-role of central cannulation.

OBJECTIVES: The purpose of this study was to assess the safety and efficacy of direct cannulation of the ascending aorta in comparison with cannulating peripheral arteries. METHODS: We retrospectively analysed type A dissection patients [n = 107; median (interquartile range [IQR]) age, 64 [53-73] years] from January 2008 to March 2018. The cohort was divided into 2 groups: direct ascending aorta cannulation (group A, n = 47; median [IQR] age, 69 [54-74] years; 34% female) and non-aortic cannulation (group B, n = 60; median [IQR] age, 62 [52-72] years; 20% female). Postoperative outcomes and long-term survival were compared. RESULTS: Baseline characteristics were not significantly different between the 2 groups, except for higher creatinine in group B (median 0.9 vs 1.1, P = 0.028) and higher prevalence of dyslipidaemia in group A (58.7% vs 38.3%, P = 0.037). Overall early mortality was 12.1% (n = 13); 12.8% (n = 6) in group A and 11.7% (n = 7) in group B (P = 0.863). The incidence of stroke was 10.6% (n = 5) in group A and 6.7% (n = 4) in group B (P = 0.463). After adjusting for CPB and circulatory arrest times, there was no group difference in the length of ICU (P = 0.257) or hospital stay (P = 0.118), all-cause reoperation (P = 0.709), peak postoperative creatinine (P = 0.426) and lactate values (n = 60; P = 0.862). Overall survival at 1, 3 and 5 years was 84%, 78% and 73%, respectively, with no difference between the 2 groups after adjustment (P = 0.629). CONCLUSIONS: Direct cannulation of the ascending aorta is a safe cannulation strategy for type A dissection repair, offering the opportunity for rapid arterial cannulation and antegrade perfusion.

The Triple HIT: Perioperative Management of Heparin-Induced Thrombocytopenia Using Plasma Exchange, Intravenous Immunoglobulin, and Protamine Infusion for Left Ventricular Assist Device Implantation.

Heparin-induced thrombocytopenia (HIT) is a serious complication in patients exposed to heparin, leading to thrombocytopenia and, potentially, thrombosis. This disorder is challenging in cardiac surgery when anticoagulation for cardiopulmonary bypass is required. Herein a patient with HIT who had active thrombosis and successfully underwent urgent left ventricular assist device implantation managed with plasma exchange, intravenous immunoglobulin, and protamine infusion is described. These therapies reduce the immune response to heparin and minimize thrombosis when heparin reexposure is planned. These approaches to perioperative management of HIT represent an attractive alternative to the use of non-heparin anticoagulants in the cardiac and vascular surgical population.

Phenytoin Pharmacokinetics During Venoarterial Extracorporeal Membrane Oxygenation and Plasma Exchange.

Currently, there is minimal guidance to antiepileptic dose adjustment for a patient requiring either venoarterial (VA) extracorporeal membrane oxygenation (ECMO) or plasma exchange (PLEX) therapy, and to our knowledge, there are rare guidances for a patient requiring both. Given the dangers with non-therapeutic concentrations of phenytoin, it is critical for the intensive care unit (ICU) practitioner to understand how the pharmacokinetic parameters of phenytoin change in critically ill patients requiring extracorporeal support. This case study presents a 41-year-old female transferred to the cardiovascular ICU requiring VA ECMO and PLEX for the treatment of systemic lupus erythematosus (SLE)-induced catastrophic antiphospholipid syndrome (CAPS). Free phenytoin concentrations were measured to assess the removal of phenytoin. There was no significant decrease in the free phenytoin concentrations post-PLEX and while on ECMO. Free phenytoin concentrations are not influenced in the setting of PLEX and while on ECMO.

Bivalirudin for Maintenance Anticoagulation During Venovenous Extracorporeal Membrane Oxygenation for COVID-19.

In its severe manifestation, coronavirus disease 2019 (COVID-19) compromises oxygenation in a manner that is refractory to maximal conventional support and requires escalation to extracorporeal membrane oxygenation (ECMO). Maintaining ECMO support for extended durations requires a delicately balanced anticoagulation strategy to maintain circuit viability by preventing thrombus deposition while avoiding excessive anticoagulation yielding hemorrhage-a task that is complicated in COVID-19 secondary to an inherent hypercoagulable state. Bivalirudin, a member of the direct thrombin inhibitor drug class, offers potential advantages during ECMO, including to its ability to exert its effect by directly attaching to and inhibiting freely circulating and fibrin-bound thrombin. Herein, the successful use of an anticoagulation strategy using the off-label use of a continuous infusion of bivalirudin in a case of severe hypoxemic and hypercarbic respiratory failure caused by COVID-19 requiring venovenous ECMO is reported. Importantly, therapeutic anticoagulation intensity was achieved rapidly with stable pharmacokinetics, and there was no need for any circuit interventions throughout the patient's 27-day ECMO course. In COVID-19, bivalirudin offers a potential option for maintaining systemic anticoagulation during ECMO in a manner that may mitigate the prothrombotic nature of the underlying pathophysiologic state.

Barrier Enclosure for Endotracheal Intubation in a Simulated COVID-19 Scenario: A Crossover Study.

INTRODUCTION: Barrier enclosures have been developed to reduce the risk of COVID-19 transmission to healthcare providers during intubation, but little is known about their impact on procedure performance. We sought to determine whether a barrier enclosure delays time to successful intubation by experienced airway operators. METHODS: We conducted a crossover simulation study at a tertiary academic hospital. Participants watched a four-minute video, practiced one simulated intubation with a barrier enclosure, and then completed one intubation with and one without the barrier enclosure (randomized to determine order). The primary outcome measure was time from placement of the video laryngoscope at the lips to first delivered ventilation. Secondary outcomes were periprocedural complications and participant responses to a post-study survey. RESULTS: Proceduralists (n = 50) from emergency medicine and anesthesiology had median intubation times of 23.6 seconds with practice barrier enclosure, 20.5 seconds with barrier enclosure, and 16.7 seconds with no barrier. Intubation with barrier enclosure averaged 4.5 seconds longer (95% confidence interval, 2.7-6.4, p < .001) than without, but was less than the predetermined clinical significance threshold of 10 seconds. Three complications occurred, all during the practice intubation. Barrier enclosure made intubation more challenging according to 48%, but 90% indicated they would consider using it in clinical practice. CONCLUSION: Experienced airway operators performed intubation using a barrier enclosure with minimal increased time to procedure completion in this uncomplicated airway model. Given potential to reduce droplet spread, use of a barrier enclosure may be an acceptable adjunct to endotracheal intubation for those familiar with its use.

Dual RVAD-ECMO Circuits to Treat Cardiogenic Shock and Hypoxemia Due to Necrotizing Lung Infection: A Case Report.

Utilization of venoarterial extracorporeal membrane oxygenation (VA-ECMO) is expanding, but dual VA-ECMO circuits to treat cardiogenic shock with refractory hypoxemia is unreported. We describe the case of combined cardiogenic and distributive shock due to necrotizing pulmonary blastomycosis. After initial central VA-ECMO cannulation, acute respiratory distress syndrome (ARDS) with increasing shunt resulted in significant central hypoxemia due to progressive ventilation-perfusion mismatch. An additional circuit provided complete oxygenation of the high circulating volume. After 4 months on support, he underwent successful heart-lung-kidney transplantation. Dual ECMO circuits are technically feasible and may be advantageous in specific circumstances of high pulmonary shunting resulting in excessive hypoxemia unbalanced with appropriate oxygen delivery.

Intraoperative Fluid Balance and Perioperative Outcomes After Aortic Valve Surgery.

BACKGROUND: The effect of intraoperative fluid balance on postoperative acute kidney injury (AKI) in cardiac surgical patients is poorly defined. METHODS: In this retrospective study of patients undergoing aortic valve replacement for aortic stenosis, the primary outcome of interest was postoperative AKI. Secondary outcomes were postoperative fluid balance, cardiac index, vasopressor use, hospital-free days, stroke, myocardial infarction, hospital readmission, and 30- and 90-day mortality. RESULTS: A total of 2327 patients were analyzed. Positive intraoperative fluid balance was associated with lower odds of AKI; the lowest odds were in the 20- to 39-mL/kg group (odds ratio, 0.56; 95% confidence interval, 0.38-0.81; P = .002). Positive intraoperative fluid balance was associated with a lower postoperative fluid balance. Increased ultrafiltration volume was associated with increased postoperative fluid resuscitation and vasopressor use. AKI was associated with increased 30- and 90-day mortality. Increased fluid balance was associated with increased odds of myocardial infarction and 30-day mortality. Increased ultrafiltration volume was associated with increased odds of 30- and 90-day mortality. CONCLUSIONS: In patients who underwent aortic valve replacement for aortic stenosis, positive intraoperative fluid balance was associated with decreased odds of AKI. Patients developing AKI had increased 30- and 90-day mortality. Although the overall incidence was low, increased intraoperative fluid balance was associated with myocardial infarction and 30-day mortality, whereas increased ultrafiltration volume was associated with 30- and 90-day morality. Prospective studies are needed to better define proper intraoperative fluid management in patients undergoing cardiac surgery.

The Perioperative Management of Ascending Aortic Dissection.

Acute aortic syndromes are a distinct group of pathologies involving the wall of the aorta that present acutely and can be potentially fatal unless treated in a timely fashion. The syndrome is dominated by aortic dissections, which comprise ≥95% of all such presentations. Those involving the ascending aorta are particularly lethal and require specific and early surgical treatment compared to dissections involving other parts of the aorta. The surgical repair of an ascending aortic dissection presents multiple challenges to the anesthesiologist. Thoughtful management throughout the perioperative period is critical for minimizing the significant morbidity and mortality associated with this condition. In this narrative review, we provide an overview of the perioperative management of patients presenting for the surgical repair of an ascending aortic dissection. Preoperative discussion focuses on assessment, hemodynamic management, and risk stratification. The intraoperative section includes an overview of anesthetic management, transesophageal echocardiographic assessment, and coagulopathy, as well as surgical considerations that may influence anesthetic management.

Pectoral Fascial (PECS) I and II Blocks as Rescue Analgesia in a Patient Undergoing Minimally Invasive Cardiac Surgery.

INTRODUCTION: Patients undergoing minimally invasive cardiac surgery have the potential for significant pain from the thoracotomy site. We report the successful use of pectoral nerve block types I and II (Pecs I and II) as rescue analgesia in a patient undergoing minimally invasive mitral valve repair. CASE REPORT: In this case, a 78-year-old man, with no history of chronic pain, underwent mitral valve repair via right anterior thoracotomy for severe mitral regurgitation. After extubation, he complained of 10/10 pain at the incision site that was minimally responsive to intravenous opioids. He required supplemental oxygen because of poor pulmonary mechanics, with shallow breathing and splinting due to pain, and subsequent intensive care unit readmission. Ultrasound-guided Pecs I and II blocks were performed on the right side with 30 mL of 0.2% ropivacaine with 1:400,000 epinephrine. The blocks resulted in near-complete chest wall analgesia and improved pulmonary mechanics for approximately 24 hours. After the single-injection blocks regressed, a second set of blocks was performed with 266 mg of liposomal bupivacaine mixed with bupivacaine. This second set of blocks provided extended analgesia for an additional 48 hours. The patient was weaned rapidly from supplemental oxygen after the blocks because of improved analgesia. CONCLUSIONS: Pectoral nerve blocks have been described in the setting of breast surgery to provide chest wall analgesia. We report the first successful use of Pecs blocks to provide effective chest wall analgesia for a patient undergoing minimally invasive cardiac surgery with thoracotomy. We believe that these blocks may provide an important nonopioid option for the management of pain during recovery from minimally invasive cardiac surgery.