Predicting mortality in nonsurgical patients before cannulation for veno-arterial extracorporeal life support: Development and validation of the LACT-8 score.

OBJECTIVES: We sought to derive and validate a model to predict inpatient mortality after veno-arterial extracorporeal life support (VA-ECLS) based on readily available, precannulation clinical data. BACKGROUND: Refractory cardiogenic shock supported by VA-ECLS is associated with high morbidity and mortality. METHODS: VA-ECLS cases at our institution from January 2014 through July 2019 were retrospectively reviewed. Exclusion criteria were cannulation: (1) at another institution; (2) for primary surgical indication; or (3) for extracorporeal cardiopulmonary resuscitation. Multivariable logistic regression compared those with and without inpatient mortality. Multiple imputation was performed and optimism-adjusted area under the curve (oAUC) values were computed. RESULTS: VA-ECLS cases from August 2019 through November 2020 were identified as a validation cohort. In the derivation cohort (n = 135), the final model included Lactate (mmol/L), hemoglobin (g/dl; Anemia), Coma (Glasgow Coma Scale [GCS] < 8) and resusciTATEd cardiac arrest (LACTATE score; oAUC = 0.760). In the validation cohort (n = 30, LACTATE showed similar predictability [AUC = 0.710]). A simplified (LACT-8) score was derived by dichotomizing lactate (>8) and hemoglobin (<8) and summing together the number of components for each patient. LACT-8 performed similarly (derivation, oAUC = 0.724; validation, AUC = 0.725). In the derivation cohort, both scores outperformed SAVE (oAUC = 0.568) and SOFA (oAUC = 0.699) scores. A LACT-8 ≥ 3 had a specificity for mortality of 97.9% and 92.9%, in the derivation and validation cohorts, respectively. CONCLUSIONS: The LACT-8 score can predict inpatient mortality prior to before cannulation for VA-ECLS. LACT-8 can be implemented utilizing clinical data without the need for an online calculator.

Bridging to lung transplantation with double-lumen venovenous extracorporeal membrane oxygenation.

BACKGROUND: Double-lumen venovenous extracorporeal membrane oxygenation may be used as a bridge to lung transplantation. Predictors of outcome with this strategy have not been well described. METHODS: All patients with irreversible lung disease who developed acute pulmonary failure and required double-lumen venovenous extracorporeal membrane oxygenation as a bridge to decision or lung transplant at our institution were included in this study. Survival of the extracorporeal membrane oxygenation patients was compared with listed patients who did not require extracorporeal membrane oxygenation with lung allocation score in the highest 10% for the same period. RESULTS: Fifteen patients (46 ± 17 years old) received double-lumen venovenous extracorporeal membrane oxygenation cannula. Mean length of extracorporeal membrane oxygenation support was 18.2 (1-60) days. Of these, seven patients were bridged to lung transplant, six died on extracorporeal membrane oxygenation, and two weaned to recovery. Amount of red blood cell transfusion was significantly higher (3.3 vs 18.5 U, p = 0.003) and lowest oxygen saturation was significantly lower in non-survivors (84.5% vs 66.3%, p = 0.002). Of the seven patients who were already listed for lung transplant at the onset of extracorporeal membrane oxygenation, five were transplanted. Overall survival to hospital discharge was 60%. Survival of patients with lung allocation score in the highest 10% (average lung allocation score 83.4) in the same period was 80%. CONCLUSION: Double-lumen venovenous extracorporeal membrane oxygenation cannula is a feasible option to bridge patients to decision or lung transplantation. Blood transfusion requirement and low oxygen saturation are markers of poor prognosis. Listing status at the time of cannulation and ambulation during extracorporeal membrane oxygenation support may be important indicators of good outcome.

Increased blood transfusion and its impact in patients having tracheostomy while on extracorporeal membrane oxygenation.

INTRODUCTION: Tracheostomy has been utilized in combination with venovenous extracorporeal membrane oxygenation (VV-ECMO) to enable early spontaneous breathing and minimize sedation requirements. Tracheostomy has been previously reported to be safe in patients supported on VV-ECMO; however, the impact of tracheostomy on blood loss in VV-ECMO patients is unknown. METHODS: We analyzed VV-ECMO patients with and without tracheostomy over a 5-year period. In order to avoid other potential sources of blood loss not related to tracheostomy or ECMO-related blood loss, patients who underwent a recent surgery prior to ECMO or during ECMO (other than tracheostomy) were excluded. RESULTS: Sixty-three patients meeting the inclusion criteria were identified (tracheostomy n=30, non-tracheostomy n=33). Tracheostomy patients were found to require more daily transfusions of red blood cells (RBC) (0.47 [0.20-1.0] vs. 0.23 [0.06-0.40] units/day, p=0.02) and total blood products (0.60 [0.32-1.0] vs. 0.31 [0.10-0.50] units/day, p=0.01). CONCLUSIONS: These results suggest that tracheostomy while on VV-ECMO predisposes patients to increased transfusion burden. Based on previous research, this increased transfusion burden could potentially be linked to increased complications and mortality.

Delayed sternal closure does not reduce complications associated with coagulopathy and right ventricular failure after left ventricular assist device implantation.

Delayed sternal closure (DSC) is occasionally adopted after implantation of left ventricular assist device (LVAD). Recent studies suggest that DSC be used for high risk group of patients with coagulopathy, hemodynamic instability or right ventricular failure. However, whether DSC is efficacious for bleeding complication or right ventricular failure is not known. This study is single center analysis of 52 patients, who underwent LVAD implantation. Of those 52 patients, 40 consecutive patients underwent DSC routinely. The sternum was left open with vacuum assist device after implantation of LVAD. Perioperative outcome of the patients who underwent routine DSC were compared with 12 patients who had immediate sternal closure (IC). Mean Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level of IC group and DSC group were 2.7 and 2.6, respectively. Postoperative bleeding (643 vs. 1469 ml, p < 0.001), duration of inotropic support (109 vs. 172 h, p = 0.034), and time to extubation (26 vs. 52 h, p = 0.005) were significantly increased in DSC group. Length of ICU stay (14 vs. 15 days, p = 0.234) and hospital stay (28 vs. 20 days, p = 0.145) were similar. Incidence of right ventricular failure and tamponade were similar in the two groups. Routine DSC after implantation of an LVAD did not prove to be beneficial in reducing complications associated with coagulopathy and hemodynamic instability including cardiac tamponade or right ventricular failure. We suggest that DSC be selectively applied for patients undergoing LVAD implant.

Emergent percutaneous therapy for left ventricular assist device retrograde flow.

With the number of heart transplants being performed each year stagnating due to lack of donors the left ventricular assist device (LVAD) patient population will continue to grow. As more and more patients are living longer with LVADs, either as a bridge to transplant or destination therapy, we will continue to see an increased number of complications related to assist device therapy. One of the common challenges physicians face are patients who suffer from both bleeding and thrombotic complications. When bleeding complications occur anticoagulation is usually reduced or discontinued and then the thrombosis risk increases. Once a pump thrombosis occurs there are limited percutaneous treatment strategies available, especially in the setting of a recent bleeding event. Surgical exchange is the only definitive therapy and that can be a high risk and difficult operation. Turning off an LVAD may become necessary, as it did in our case, but that can lead to significant retrograde flow through the device and rapid patient decline. A prompt percutaneous therapy is needed to stabilize these patients.

Developing an Extracorporeal Membrane Oxygenation Program.

The development of a successful extracorporeal membrane oxygenation (ECMO) program requires an institutional commitment and the multidisciplinary cooperation of trained specialty personnel from nursing, internal medicine, anesthesiology, pulmonology, emergency medicine, critical care, and surgery and often pediatrics as well. The specialized training necessary to cultivate an integrated team capable of providing life-saving ECMO cannot be underestimated. The development of a successful ECMO program is best suited to a tertiary medical center that is centrally/regionally located and capable of financially supporting the level of expertise required as well as managing the program's overall cost effectiveness.

Safety of Nurse-Led Ambulation for Patients on Venovenous Extracorporeal Membrane Oxygenation.

PURPOSE: Venovenous extracorporeal membrane oxygenation (VV ECMO) is an effective therapy in patients with acute lung injury and end-stage lung disease. Although immobility increases the risk of complications, ambulation of patients on VV ECMO is not the standard of care in many institutions. Staff concerns for patient safety remain a barrier to ambulation. In this case series, we present our experience utilizing a nurse-driven ambulatory VV ECMO process to safely rehabilitate patients. METHODS: We retrospectively reviewed all VV ECMO cases at our institution between January 1, 2011, and November 1, 2013. Inclusion criteria for this study required patients to be cannulated in the right internal jugular vein and ambulated while on VV ECMO. RESULTS: During the period from January 1, 2011, to November 1, 2013, 18 patients (mean age 49 ± 15 years, 12 male) were ambulated while on ECMO. Eight received a transplant and survived to discharge. Of the remaining patients, 4 were successfully weaned from VV ECMO and 6 died following decisions by the family to withdraw care. The mean duration of VV ECMO support was 18 ± 16 days with the maximum duration being 61 days. All patients received physical therapy, range of motion at the bedside, and ambulated in the hospital. There were no patient falls, decannulations, or any other complications related to ambulation. CONCLUSION: The adoption of a nurse-driven program to ambulate patients on VV ECMO is safe and may reduce other complications associated with immobility.