Outcomes after extracorporeal membrane oxygenation support in COVID-19 and non-COVID-19 patients.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (V-V ECMO) support is increasingly used in the management of COVID-19-related acute respiratory distress syndrome (ARDS). However, the clinical decision-making to initiate V-V ECMO for severe COVID-19 still remains unclear. In order to determine the optimal timing and patient selection, we investigated the outcomes of both COVID-19 and non-COVID-19 patients undergoing V-V ECMO support. METHODS: Overall, 138 patients were included in this study. Patients were stratified into two cohorts: those with COVID-19 and non-COVID-19 ARDS. RESULTS: The survival in patients with COVID-19 was statistically similar to non-COVID-19 patients (p = .16). However, the COVID-19 group demonstrated higher rates of bleeding (p = .03) and thrombotic complications (p < .001). The duration of V-V ECMO support was longer in COVID-19 patients compared to non-COVID-19 patients (29.0 ± 27.5 vs 15.9 ± 19.6 days, p < .01). Most notably, in contrast to the non-COVID-19 group, we found that COVID-19 patients who had been on a ventilator for longer than 7 days prior to ECMO had 100% mortality without a lung transplant. CONCLUSIONS: These findings suggest that COVID-19-associated ARDS was not associated with a higher post-ECMO mortality than non-COVID-19-associated ARDS patients, despite longer duration of extracorporeal support. Early initiation of V-V ECMO is important for improved ECMO outcomes in COVID-19 ARDS patients. Since late initiation of ECMO was associated with extremely high mortality related to lack of pulmonary recovery, it should be used judiciously or as a bridge to lung transplantation.

Limb ischemia and bleeding in patients requiring venoarterial extracorporeal membrane oxygenation.

OBJECTIVE: Acute limb ischemia (ALI) and cannulation site bleeding are frequent complications of venoarterial (VA) extracorporeal membrane oxygenation (ECMO) and are associated with worse outcomes. The goals of this study were to assess our rates of ECMO-related ALI and bleeding and to evaluate the efficacy of strategies to prevent them, such as distal perfusion cannula (DPC) and ultrasound-guided cannulation. METHODS: This is a single-center retrospective cohort study of adult patients placed on peripheral VA-ECMO at a tertiary medical center between 2014 and 2018. ALI was defined as new ischemia of the extremity ipsilateral to arterial cannulation. Significant cannulation site bleeding was defined as excessive bleeding requiring intervention (eg, transfusion or reoperation). Univariate analyses were used to identify factors associated with ALI, bleeding, and in-hospital mortality. RESULTS: During the study period, 105 patients were placed on peripheral VA-ECMO (61.3% female; mean age, 54.9 ± 14.8 years). Nearly half (46.6%) had ECMO implantation in an extracorporeal cardiopulmonary resuscitation setting and 37 (44.0%) had a DPC. Average duration of support was 5.6 ± 5.0 days. Overall in-hospital mortality and death on ECMO support were 65.1% and 50%, respectively. ALI occurred in 21 (20%) and cannulation-related bleeding occurred in 24 (22.9%) patients who were treated with a total of 27 procedures, including thromboembolectomy (22.2%), vascular repair (18.5%), and fasciotomy (25.9%). On univariate analysis, cannulation in the operating room (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.08-0.77; P = .02) was associated with decreased risk of ALI, whereas cannulation in the operating room (OR, 2.65; 95% CI, 1.09-6.45; P = .03) and cutdown approach (OR, 4.96; 95% CI, 2.32-10.61; P < .0001) were associated with increased risk of bleeding. Ultrasound-guided placement was associated with decreased risk of bleeding (OR, 0.81; 95% CI, 0.04-0.84; P = .03). DPC was not associated with either ALI (P = .47) or bleeding (P = .06). ALI (OR, 2.68; 95% CI 1.03-6.98; P = .04), age (OR, 1.94; 95% CI, 1.03-3.69; P = .04), and worse baseline heart failure (OR, 2.01; 95% CI, 1.02-3.97; P = .04) were associated with greater risk of in-hospital mortality. Ultrasound-guided cannulation (OR, 0.41; 95% CI, 0.20-0.87; P = .02) was associated with decreased risk of in-hospital mortality. CONCLUSIONS: ALI and significant bleeding are common occurrences after peripheral VA-ECMO cannulation. Whereas DPC placement did not significantly decrease risk of ALI, ultrasound-guided cannulation decreased the risk of bleeding. Cannulation in the operating room is associated with decreased risk of ALI at the expense of increased risk of bleeding. ALI, older age (≥65 years), and worse heart failure increased risk of in-hospital mortality.

Ankle-brachial index to monitor limb perfusion in patients with femoral venoarterial extracorporeal membrane oxygenation.

BACKGROUND: Limb ischemia is a major complication of femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO). Use of ankle-brachial index (ABI) to monitor limb perfusion in VA-ECMO has not been described. We report our experience monitoring femoral VA-ECMO patients with serial ABI and the relationships between ABI and near infrared spectroscopy (NIRS). METHODS: This is a retrospective single-center review of consecutive adult patients placed on femoral VA-ECMO between January 2019 and October 2019. Data were collected on patients with paired ABI and NIRS values. Relationships between NIRS and ABI of the cannulated (E-NIRS and E-ABI) and non-cannulated legs (N-NIRS and N-ABI) along with the difference between legs (d-NIRS and d-ABI) were determined using Pearson correlation. RESULTS: Overall, 22 patients (mean age 56.5 ± 14.0 years, 72.7% male) were assessed with 295 E-ABI and E-NIRS measurements, and 273 N-ABI and N-NIRS measurements. Mean duration of ECMO support was 129.8 ± 78.3 h. ECMO-mortality was 13.6% and in-hospital mortality was 45.5%. N-ABI and N-NIRS were significantly higher than their ECMO counterparts (ABI mean difference 0.16, 95% confidence interval [CI]: 0.13-0.19, p < .0001; NIRS mean difference 2.51, 95% CI: 1.48-3.54, p < .0001). There was no correlation between E-ABI versus E-NIRS (r = .032, p = .59), N-ABI versus N-NIRS (r = .097, p = .11), or d-NIRS versus d-ABI (r = .11, p = .069). CONCLUSION: ABI is a quantitative metric that may be used to monitor limb perfusion and supplement clinical exams to identify limb ischemia in femorally cannulated VA-ECMO patients. More studies are needed to characterize the significance of ABI in femoral VA-ECMO and its value in identifying limb ischemia in this patient population.

Outcomes of 3-day discharge after elective cardiac surgery.

BACKGROUND: Shorter length of stay (LOS) is a welcome consequence of optimized perioperative care. However, accelerated hospital discharge may have unintended consequences. Before implementing an institutional enhanced recovery after surgery protocol, we evaluated the safety of shorter LOS and compared outcomes of patients with shorter LOS (LOS ≤ 3 days) to those with longer LOS (LOS > 3 days). METHODS: We identified all patients undergoing elective cardiac surgery with cardiopulmonary bypass between July 2004 and June 2017. Transcatheter approaches, ventricular assist devices, transplants, and traumas were excluded. Patients were divided into two cohorts, one with shorter hospitalizations (LOS ≤ 3 days) and one with longer hospitalizations (LOS > 3 days). Propensity score matching (PSM) was performed and differences between the two groups were compared. RESULTS: A total of 5,987 patients (63.0 ± 13.8 years old, 34% female) were identified and 131 (2.2%) patients were LOS ≤ 3 days; median STS Risk score was 1.2 (0.6-2.4). PSM resulted in a total of 478 patients (357 LOS > 3 and 121 LOS ≤ 3 days); median STS Risk score was 0.4 (0.3-0.9). LOS ≤ 3 days had lower rates of postoperative atrial fibrillation (2% vs. 19%; p < .001) and major in-hospital complications (0% vs. 9%; p = .001); however, 30-day readmissions (8% LOS ≤ 3 vs. 6% LOS > 3 days; p = .66) and mortality rates (0% vs. 0%) were comparable between the two groups. CONCLUSION: LOS ≤ 3 days was associated with less postoperative atrial fibrillation and fewer major in-hospital complications. LOS ≤ 3 days was not associated with rehospitalization or mortality. Shorter LOS after elective cardiac surgery appears to be a safe practice with favorable outcomes, especially in low operative risk patients.

Pre-Intubation Veno-Venous Extracorporeal Membrane Oxygenation in Patients at Risk for Respiratory Decompensation.

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) has emerged as a potential life-saving treatment for patients with acute respiratory failure. Given the accumulating literature supporting the use of VV-ECMO without therapeutic levels of anticoagulation, it might be feasible to use it for planned intubation before surgical procedures. Here, we report consecutive series of patients who underwent planned initiation of VV-ECMO, without anticoagulation, before induction of general anesthesia for anticipated difficult airways or respiratory decompensation. We describe the approach to safely initiate VV-ECMO in an awake patient. We retrospectively identified patients in a prospectively maintained database who underwent planned initiation of VV-ECMO before intubation. Standard statistical methods were used to determine post-procedure outcomes. Patients included were three men and one woman, with a mean age of 34.3 ± 10.4 years. Indications included mediastinal lymphoma, foreign body obstruction, hemoptysis, and tracheo-esophageal fistula. VV-ECMO was initiated electively for all patients, and no anticoagulation was used. The median duration of VV-ECMO support was 2.5 days (1-11 days), the median length of ventilator dependence and intensive care unit stay was 1 day (1-23 days) and 5 days (4-31 days), respectively. The median length of stay was 18.5 days (8-39 days). There were no thrombotic complications and no mortality at 30 days. Initiation of awake VV-ECMO is feasible and is safe before intubation and induction of anesthesia in patients at high risk for respiratory decompensation.

Indwelling Central Venous Catheters Drive Bloodstream Infection During Veno-venous Extracorporeal Membrane Oxygenation Support.

Blood stream infection (BSI) is a potentially lethal complication in patients receiving extracorporeal membrane oxygenation (ECMO). It may be particularly common in patients with veno-venous ECMO due to their long hospitalization in the intensive care unit. Given that these patients have concurrent indwelling central venous catheters (CVC), it is unclear whether the ECMO circuit, CVC, or both, contribute to BSI. This study evaluated the risk factors associated with BSI in patients receiving veno-venous ECMO in a single institution study of 61 patients from 2016 through 2019. All ECMO catheters and the circuit oxygenator fluid were aseptically collected and analyzed for microorganisms at the time of decannulation. New BSI was diagnosed in 15 (24.6%) patients and increased mortality by threefold. None of the ECMO catheters or oxygenator fluid were culture positive. BSI increased with CVC use of over 8 days and was significantly lowered when CVC were exchanged by day 8 compared with patients with exchanges at later points (15.0% vs. 42.8%, p = 0.02). Median length of CVC use in the BSI-negative and BSI-positive group were 6.3 ± 5.0 and 9.4 ± 5.1, respectively (p = 0.04). In summary, BSI is a potentially lethal complication in patients receiving ECMO. Indwelling CVC, not the ECMO circuitry, is the likely contributor for BSI, and exchanging CVC by day 8 can reduce the incidence of BSI.

Feasibility of Venovenous Extracorporeal Membrane Oxygenation Without Systemic Anticoagulation.

BACKGROUND: Venovenous extracorporeal membrane oxygenation (ECMO) is increasingly being used for acute respiratory distress syndrome and as a bridge to lung transplantation. After initiation of venovenous ECMO, systemic anticoagulation therapy is traditionally administered and can cause bleeding diathesis. Here, we investigated whether venovenous ECMO can be administered without continuous systemic anticoagulation administration for patients with acute respiratory distress syndrome. METHODS: This is a retrospective review of an institutional ECMO database. We included consecutive patients from January 2015 through February 2019. Overall, 38 patients received low levels of continuous systemic anticoagulation (AC+) whereas the subsequent 36 patients received standard venous thromboprophylaxis (AC-). Published Extracorporeal Life Support Organization guidelines were used for the definition of outcomes and complications. RESULTS: Overall, survival was not different between the two groups (P = .58). However, patients in the AC+ group had higher rates of gastrointestinal bleeding (28.9%, vs AC- group 5.6%; P < .001). The events per patient-day of gastrointestinal bleeding was 0.00025 in the AC- group and 0.00064 in the AC+ group (P < .001). In addition, oxygenator dysfunction was increased in the AC+ group (28.9% and 0.00067 events per patient-day, vs AC- 11.1% and 0.00062 events per patient-day; P = .02). Furthermore, the AC+ group received more transfusions: packed red blood cells, AC+ group 94.7% vs AC- group 55.5% (P < .001); fresh frozen plasma, AC+ 60.5% vs AC- 16.6% (P = .001); and platelets, AC+ 84.2% vs AC- 27.7% (P < .001). There was no circuit thrombosis in either groups throughout the duration of ECMO support. CONCLUSIONS: Our results suggest that venovenous ECMO can be safely administered without continuous systemic anticoagulation therapy. This approach may be associated with reduced bleeding diathesis and need for blood transfusions.

Prognosis of Severe Asymptomatic Aortic Stenosis With and Without Surgery.

BACKGROUND: This study sought to determine outcomes in patients with severe, asymptomatic aortic stenosis (AS), stratified by treatment recommendation. METHODS: Between January 2005 and December 2013, 4,998 patients had severe AS by echocardiography, of whom 308 were identified as asymptomatic by medical record review. Five patients were deemed inoperable, and 38 were lost to follow-up. Of the remaining 265 patients, aortic valve replacement (AVR) was recommended in 104, and watchful waiting (WW) was recommended in 161. Probabilities of undergoing surgery and of death from recommendation date were estimated using a multistate model. Cox regression analysis was used to determine independent risk factors for death. RESULTS: Probability of death at 1 year after recommendation was 5.2% in the WW group and 4.7% in the AVR group. At 2 years after recommendation, survival in the AVR-recommended group was 92.5% versus 83.9% in the WW group (p = 0.044). In the WW group, the probability of dying or undergoing surgery was 43.9% by 2 years. Undergoing surgery was independently associated with higher survival in the AVR-recommended group (hazard ratio [HR], 0.17; p = 0.038) and in the WW group (HR, 0.39; p = 0.044). A higher ejection fraction (HR, 0.58; p < 0.001) was associated with better survival, whereas renal failure (HR, 2.81; p = 0.009) was associated with worse survival. CONCLUSIONS: The strategy of early AVR is associated with improved survival in asymptomatic patients.

Quality of Operative Performance Feedback Given to Thoracic Surgery Residents Using an App-Based System.

OBJECTIVE: Residents frequently report inadequate feedback both in quantity and quality. The study evaluates the quality of faculty feedback about operative performance given using an app-based system. DESIGN: Residents requested operative performance evaluation from faculty on a real-time basis using the "Zwisch Me!!" mobile application which allows faculty to provide brief written feedback. Qualitative analysis of feedback was performed using grounded theory. SETTING: The 7 academic medical centers with thoracic surgery training programs. PARTICIPANTS: Volunteer thoracic surgery residents in both integrated and traditional training pathways and their affiliated cardiothoracic faculty. RESULTS: Residents (n = 33) at 7 institutions submitted a total of 596 evaluations to faculty (n = 48). Faculty acknowledged the evaluation request in 476 cases (80%) and in 350 cases (74%) provided written feedback. Initial open coding generated 12 categories of feedback type. We identified 3 overarching themes. The first theme was the tone of the feedback. Encouraging elements were identified in 162 comments (46%) and corrective elements in 230 (65%). The second theme was the topic of the feedback. Surgical technique was the most common category at 148 comments (42.2%) followed by preparation for case (n = 69, 19.7%). The final theme was the specificity of the feedback. Just over half of comments (n = 190, 54.3%) contained specific feedback, which could be applied to future cases. However, 51 comments (14.6%) contained no useful information for the learners. CONCLUSIONS: An app-based system resulted in thoracic surgery residents receiving identifiable feedback in a high proportion of cases. In over half of comments the feedback was specific enough to allow improvement. Feedback was better quality when addressing error prevention and surgical technique but was less useful when addressing communication, flow of the case, and assisting. Faculty development around feedback should focus on making feedback specific and actionable, avoiding case descriptions, or simple platitudes.