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The effect of using donation after circulatory death (DCD) hearts on waitlist outcomes has not been substantiated. We retrospectively analyzed 184 heart transplant (HT) candidates at our institution from 2019 to 2021. Patients were stratified into 2 observation periods centered on September 12, 2020, when the adult DCD HT program officially began. The primary outcome was a comparison of transplant rate between period 1 (pre-DCD) and period 2 (post-DCD). Secondary outcomes included waitlist time-to-transplant, waitlist mortality rate, independent predictors of incidence of HT, and posttransplant outcomes. A total of 165 HTs (n = 92 in period 1 and n = 73 in period 2) were performed. The median waitlist time-to-transplant decreased from 47.5 to 19 days in periods 1 and 2, respectively (P = .004). The transplant rate increased from 181 per 100 patient-years in period 1 to 579 per 100 patient-years in period 2 (incidence rate ratio, 1.87; 95% CI, 1.04-3.38; P = .038). There were no statistical differences in waitlist mortality rate (P = .566) and 1-year survival (P = .699) between the 2 periods. DCD HTs (n = 36) contributed to 49.3% of overall HT activity in period 2. We concluded that utilization of DCD hearts significantly reduced waitlist time and increased transplant rate. Short-term posttransplant outcomes were comparable between the pre-DCD and post-DCD periods., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Victor Pretorius reports a relationship with Abbott that includes: speaking and lecture fees. Dr. Victor Pretorius reports a relationship with Medtronic Inc that includes: speaking and lecture fees. Dr. Victor Pretorius reports a relationship with TransMedics Inc that includes: funding grants. Dr. Eric Adler reports a relationship with TransMedics Inc that includes: funding grants., (Copyright © 2023 American Society of Transplantation & American Society of Transplant Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Extracorporeal membrane oxygenation (ECMO) has frequent and sometimes lethal thrombotic complications. The role that activated platelets, leukocytes, and small (0.3-micron to 1-micron) extracellular vesicles (EVs) play in ECMO thrombosis is not well understood., Objectives: To test the effect of blood flow rate on the generation of activated platelets, leukocytes, and EVs in a simulated neonatal ECMO circuit using heparinized human whole blood., Methods: Simulated neonatal roller pump circuits circulated whole blood at low, nominal, and high flow rates (0.3, 0.5, and 0.7 L/min) for 6 h. Coagulopathy was defined by thromboelastography (TEG), STA ® -procoagulant phospholipid clot time (STA ®- Procoag-PPL), and calibrated automated thrombogram. High-resolution flow cytometry measured the cellular expression of prothrombotic phospholipids and proteins on platelets, leukocytes, and EV., Results: Despite heparinization, occlusive thrombosis halted flow in two of five circuits at 0.3 L/min and three of five circuits at 0.7 L/min. None of the five circuits at 0.5 L/min exhibited occlusive thrombosis. Phosphatidylserine (PS)-positive platelets and EVs increased at all flow rates more than blood under static conditions (P < .0002). Tissue factor (TF)-positive leukocytes and EVs increased only in low-flow and high-flow circuits (P < .0001). Tissue factor pathway inhibitor (TFPI), at 50 times more than the concentration in healthy adults, failed to suppress thrombin initiation in low-flow and high-flow circuits., Conclusions: This in vitro study informs ECMO specialists to avoid low and high blood flow that increases TF expression on leukocytes and EVs, which likely initiate clot formation. Interventions to decrease TF generated by ECMO may be an effective approach to decrease thrombosis., (© 2019 International Society on Thrombosis and Haemostasis.)

Background: We investigated effects of mesenchymal stem cells (MSC) or low-flow extracorporeal life support (ECLS) as adjunctive treatments for acute respiratory distress syndrome (ARDS) due to inhalation injury and burns. We hypothesized that these interventions decrease histological end-organ damage., Methods: Anesthetized female swine underwent smoke inhalation injury and 40% TBSA burns, then critical care for 72h. The following groups were studied: CTR (no injury, n = 4), ICTR (injured untreated, n = 10), Allo (injured treated with allogenic MSC, n = 10), Auto (injured treated with autologous MSC, n = 10), Hemo (injured and treated with the Hemolung low flow ECLS system, n = 9), and Nova (injured and treated with the NovaLung low flow ECLS system, n = 8). Histology scores from lung, kidneys, liver, and jejunum were calculated. Data are presented as means±SEM., Results: Survival at 72h was 100% in CTR; 40% in ICTR; 50% in Allo; 90% in Auto; 33% in Hemo; 63% in Nova. ARDS developed in 0/10 CTR; 10/10 ICTR; 8/9 Hemo; 5/8 Nova; 9/10 Allo; 6/10 Auto. Diffuse alveolar damage (DAD) was present in all injured groups. MSC groups had significantly lower DAD scores than ICTR animals (Allo 26.6 ± 3.4 and Auto 18.9 ± 1.5 vs. ICTR 46.8 ± 2.1, p < 0.001). MSC groups also had lower DAD scores than ECLS animals (Allo vs. Nova, p < 0.05, Allo vs. Hemo p < 0.001, Auto vs. Nova p < 0.001, Auto vs. Hemo, p < 0.001). Kidney injury ICTR (p < 0.05) and Hemo (p < 0.01) were higher than in CTR. By logistic regression, a PaO 2 -to-FiO 2 ratio (PFR) < 300 was a function of the DAD score: logit (PFR < 300) = 0.84 + 0.072*DAD Score, odds ratio 1.074 (1.007, 1.147, p < 0.05) with a ROC AUC of 0.76, p < 0.001., Conclusion: Treatment with Auto MSC followed by Allo and then Nova were most effective in mitigating ARDS and MOF severity in this model. Further studies will elucidate the role of combination therapies of MSC and ECLS as comprehensive treatments for ARDS and MOF., (Copyright © 2019 Elsevier Ltd and ISBI. All rights reserved.)

Introduction: Extracorporeal Membrane Oxygenation (ECMO) has only recently been described in patients with burn injuries. We report the incidence and type of infections in critically ill burn and non-burn patients receiving ECMO., Methods: A retrospective chart review was performed on all patients at Brooke Army Medical Center who received ECMO between September 2012 and May 2018., Results: 78 patients underwent ECMO. Approximately half were men with a median age of 34 years with a median time on ECMO of 237 h (IQR 121-391). Compared to patients without burns (n = 58), patients with burns (n = 20) had no difference in time on ECMO, but had more overall infections (86 vs. 31 per 1000 days, p = 0.0002), respiratory infections (40 vs. 15 per 1000 days, p = 0.01), skin and soft tissue infections (21 vs. 5 per 1000 days, p = 0.02) and fungal infections (35% vs 10%, p = 0.02). Twenty percent of bacterial burn infections were due to drug resistant organisms., Conclusion: This is the first study to describe the incidence of infection in burn injury patients who are undergoing ECMO. We observed an increase in infections in burn patients on ECMO compared to non-burn patients. ECMO remains a viable option for critically ill patients with burn injuries., (Published by Elsevier Ltd.)

Background: The prevalence of acute respiratory distress syndrome (ARDS) in mechanically ventilated burn patients is 33%, with mortality varying from 11-46% depending on ARDS severity. Despite the new Berlin definition for ARDS, prompt bedside diagnosis is lacking. We developed and tested a bedside technique of fiberoptic-bronchoscopy-based optical coherence tomography (OCT) measurement of airway mucosal thickness (MT) for diagnosis of ARDS following smoke inhalation injury (SII) and burns., Methods: 16 female Yorkshire pigs received SII and 40% thermal burns. OCT MT and PaO 2 -to-FiO 2 ratio (PFR) measurements were taken at baseline, after injury, and at 24, 48, and 72h after injury., Results: Injury led to thickening of MT which was sustained in animals that developed ARDS. Significant correlations were found between MT, PFR, peak inspiratory pressure (PIP), and total infused fluid volume., Conclusions: OCT is a useful tool to quantify MT changes in the airway following SII and burns. OCT may be effective as a diagnostic tool in the early stages of SII-induced ARDS and should be tested in humans., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

Inhalation injury commonly accompanies thermal injury, increasing the likelihood of mortality and multiple organ dysfunction (MOD). Large animal models have given important insight into the pathophysiology of this injury; however recapitulating late MOD has remained difficult. The current report describes experiments using a smoke inhalation and burn model, with follow-up of ambulatory swine for 14days with bronchoscopy, CT scanning, and bronchoalveolar lavage fluid (BALF)/blood collection. Clinically, animals cleared airway damage in the first several days after-injury. This was mirrored with erythematous airways on day 2 after-injury, which resolved by the end of the experiment, as did parenchymal damage seen on CT. An initial rise in the protein content of BALF immediately after-injury was followed by a dramatic increase in the concentration of leukocytes. Circulating neutrophils increased while lymphocytes decreased; both correlated with cell counts in BALF. IL8 levels in BALF increased 30-fold and remained elevated throughout the experiment. IL1ra increased circulation immediately after-injury, and afterwards in BALF. Other cytokines (TNFα, IL12) transiently increased in BALF (and decreased in circulation) on day 2. Taken together, these results display a remarkable capability for the lungs to recover in the absence of intubation, with further evidence of the role of cytokines such as IL8 and IL1ra. The possible exacerbating effects of clinical practices such as ventilation and bronchoscopies should be considered., (Published by Elsevier Ltd.)

Purpose: Compare virtual bronchoscopy (VB) to fiberoptic bronchoscopy (FOB) for scoring smoke inhalation injury (SII)., Methods: Swine underwent computerized tomography (CT) with VB and FOB before (0) and 24 and 48 h after SII. VB and FOB images were scored by 5 providers off line., Results: FOB and VB scores increased over time (p<0.001) with FOB scoring higher than VB at 0 (0.30±0.79 vs. 0.03±0.17), 24 h (4.21±1.68 vs. 2.47±1.50), and 48h (4.55±1.83 vs. 1.94±1.29). FOB and VB showed association with PaO2-to-FiO2 ratios (PFR) with areas under receiver operating characteristic curves (ROC): for PFR≤300, VB 0.830, FOB 0.863; for PFR≤200, VB 0.794, FOB 0.825; for PFR≤100, VB 0.747, FOB 0.777 (all p<0.001). FOB showed 80.3% specificity, 77% sensitivity, 88.8% negative-predictive value (NPV), and 62.3% positive-predictive value (PPV) for PFR≤300 and VB showed 67.2% specificity, 85.5% sensitivity, 91.3% NPV, and 53.4% PPV., Conclusions: VB provided similar injury severity scores to FOB, correlated with PFR, and reliably detected airway narrowing. VB performed during admission CT may be a useful screening tool specifically to demonstrate airway narrowing induced by SII., (Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.)

A prolonged and fulminant inflammatory state, with high levels of pro- and anti-inflammatory mediators, is seen after extensive thermal injury. Blood purification techniques including plasma exchange, continuous venovenous hemofiltration, and adsorbing membranes have the potential to modulate this response, thereby improving outcomes. This article describes the scientific rationale behind blood purification in burns and offers a review of literature regarding its potential application in this patient cohort., (Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.)

This study focused on the impact of noise on the reliability of heart-rate variability and complexity (HRV, HRC) to discriminate between different trauma patients and to monitor individual patients. Life-saving interventions (LSIs) were chosen as an endpoint because performance of LSIs is a critical aspect of trauma patient care. Noise was modeled and simulated by modifying original R-R interval (RRI) sequences via decimation, concatenation, and division of RRIs, as well as R-wave detection using the electrocardiogram. Results showed that under increasing simulated noise, entropy and autocorrelation measures can still effectively discriminate between LSI and non-LSI patients and monitor individuals over time., (© 2013 Elsevier Ltd. All rights reserved.)

Introduction: In this study we explored direct and indirect measures of autonomic nervous system function, as well as changes in cardiovascular complexity, during hemorrhagic shock (HS)., Methods: HS was induced in anesthetized sheep (n=8) by removing 40 ml/kg of blood in four 10 ml/kg steps over 40 min. Resuscitation was performed with lactated Ringer's and re-infusion of shed blood. Renal sympathetic nerve activity (RSNA) was measured by microneurography. Spectral analysis of heart rate variability (HRV) employed fast-Fourier transformation of the R-to-R interval (RRI) of the EKG. This generated the normalized high-frequency (HFnu) and low-frequency (LFnu) powers of the RRI, and their ratio (LFnu/HFnu, a proposed index of sympatho-vagal balance). Additionally, non-linear methods were applied: RRI complexity was measured by approximate (ApEn) and sample (SampEn) entropy methods; RRI fractal dimension was measured by curve lengths (FDCL). Plasma catecholamines were determined by HPLC., Results: The model caused profound HS; 2/8 animals survived till the end of resuscitation. RSNA increased in 7/8 sheep and, as HS progressed, multiple burst complexes were identified followed by sympathetic withdrawal. Concomitant decreases in HFnu and increases in LFnu/HFnu occurred after 20 ml/kg blood loss. ApEn and FDCL decreased after withdrawal of 40 ml/kg of blood. Catecholamine concentrations increased throughout HS. LFnu/HFnu and RSNA were not linearly correlated., Conclusions: HS led to an increase in RSNA with subsequent withdrawal. LFnu/HFnu increased during HS in association with vagal withdrawal and loss of RRI complexity. RRI complexity may in part reflect vagal modulation of the heart rate. Changes in directly measured tonic sympathetic traffic do not correlate with non-invasive measures of autonomic modulation of the heart.