The aspartate transaminase/alanine transaminase (DeRitis) ratio predicts mid-term mortality and renal and respiratory dysfunction after left ventricular assist device implantation.

OBJECTIVES: Preoperative liver dysfunction is a well-known risk factor for adverse events after major surgery. However, there is only little data regarding the precise role of the Model of End-Stage Liver Disease (MELD) score and the De Ritis ratio (DRR, alanine transaminase/aspartate aminotransferase) as a predictor for outcome after left ventricular assist device (LVAD) implantation. METHODS: A retrospective analysis of all patients undergoing LVAD implantation at our institution between January 2012 and August 2014 was performed. The primary outcome was survival at 180 days after surgery. RESULTS: During the observation period, 63 patients underwent LVAD implantation (mean age 59.9 ± 8.3 years, 50% male). Mean preoperative ejection fraction was 16.3 ± 7.7, 13 patients required preoperative renal replacement therapy and 9 patients were on extracorporeal life support. Mean Interagency Registry for Mechanically Assisted Circulatory Support level was 2.8 ± 1.3, mean preoperative MELD was 12.7 ± 7.2, mean preoperative DRR was 2.01 ± 4.4. Aspartate aminotransferase (102 ± 220.8 vs 57.8 ± 123.4 U/l, P = 0.041), MELD score (16.1 ± 8.8 vs 11.4 ± 6.1, P = 0.017) and DRR (4.2 ± 7.8 vs 1.1 ± 1.1, P = 0.001) were significantly higher in non-survivors than in survivors after 180 days. Using logistic regression analyses, a DRR >1.37 was an independent predictor for 30-day mortality [odds ratio (OR) 4.5] and 180-day mortality (OR 4.1). In addition, the DRR was associated with postoperative acute kidney injury with need for renal replacement therapy (OR 4.2) and prolonged postoperative ventilation time >72 h (OR 3.8). Using receiver operator characteristics analyses, DRR showed a sensitivity of 0.80 and a specificity of 0.81 (area under the curve 0.834, cut-off 1.37) for 180-day mortality. CONCLUSIONS: The DRR is predictive of early and mid-term mortality as well as relevant morbidities in patients undergoing LVAD implantation. Therefore, the DRR should be considered within the preoperative risk stratification and patient selection for LVAD implantation.

Does Traumatic Donor Cause of Death Influence Outcome after Lung Transplantation? A Single-Centre Analysis.

Background Owing to the shortage of donor organs in lung transplantation (LuTX), liberalization of donor selection criteria has been proposed. However, some studies suggested that donor traumatic brain damage might influence posttransplantation allograft function. This article aimed to investigate the association of donor cause of death (DCD) and outcome after LuTX. Methods A retrospective analysis of 186 consecutive double LuTXs at our institution from January 2000 to December 2008 was performed. DCD was categorized into traumatic brain injury (TBI) and nontraumatic brain injury (NTBI). In addition, NTBI was sub classified as spontaneous intracerebral bleeding (B), hypoxic brain damage (H), and intracerebral neoplasia (N). Results DCD was classified as TBI in 50 patients (26.9%) and NTBI in 136 patients (73.1%): B in 112 patients (60.2%), H in 21 patients (11.3%), and N in 3 patients (1.6%). Young male donors predominated in group TBI (mean age 36.0 ± 14.5 vs. 42.8 ± 10.7, p < 0.01; 29 males in the TBI group [58.0%] vs. 48 males in the NTBI group [35.3%], p < 0.01). Groups of DCD did not differ significantly by recipient age or gender, recipient diagnosis, donor ventilation time, or paO2/FiO2 before harvesting. TBI donors received significantly more blood (3.4 ± 3.8 vs. 1.8 ± 1.9, p = 0.03). A chest trauma was evident only in group T (n = 7 [3.7%] vs. 0 [0%], p < 0.001). Mode of donor death did not affect the following indices of graft function: length of postoperative ventilation, paO2/FiO2 ratio up to 48 hours, and lung function up to 36 months. One- and three-year survival was comparable with 84.4 and 70.4% for TBI donors versus 89.4% and 69.2% for NTBI donors. Five-year survival tended to be lower in the TBI group but did not reach statistical significance (43.4 vs. 53.9%). Conclusion This study indicates that traumatic DCD does not affect outcome after LuTX. These results can be achieved with an ideal donor management combined with an individual case-to-case evaluation by an experienced LuTX surgeon.

Is universal antifungal prophylaxis mandatory in adults after lung transplantation? A review and meta-analysis of observational studies.

BACKGROUND: Lung transplant (LTX) recipients are at high risk of invasive Aspergillus infections (IAI). However, no randomized-controlled trials (RCT) or international guidelines on antifungal prophylaxis (AFP) in the LTX population exist. METHODS: A meta-analysis was performed to determine whether AFP reduces the rate of IAI after LTX. A total of six eligible observational studies (five with no prophylaxis, one with targeted prophylaxis, three studies including heart/lung transplantation) with a total of 748 patients were included. RESULTS: The pooled odds ratio (OR) for IAI (62 IFI in the intervention arm and 82 in the control group) was 0.234 (95% confidence interval [CI] 0.097-0.564, P=0.001, z=-3.237). Pooled studies were characterized by substantial heterogeneity (I2 =66.64%); number needed to treat was 6.8. A subgroup analyses with exclusion of heart transplant recipients also showed a statistically significant reduction in IAI with AFP (OR 0.183, 95% CI 0.0449-0.744, P=0.018). CONCLUSION: This study suggests that universal antifungal prophylaxes reduces incidence of IAI after LTX. However, included studies are limited by small sample size, single-center structure without randomization, mixed population (including heart/heart-lung transplant), and heterogeneity due to variations in immunosuppression, type, and duration of AFP. Therefore, there is a clear need for an adequately powered RCT.

Safety and Efficiency of Percutaneous Dilatational Tracheostomy With Direct Bronchoscopic Guidance for Thoracic Transplant Recipients.

BACKGROUND: Percutaneous dilatational tracheostomy (PDT) is the standard airway access in critically ill patients who require prolonged mechanical ventilation. However, the literature lacks reports about the effectiveness and safety of this procedure in thoracic organ transplant recipients, who have increased risks of bleeding and infection. METHODS: We retrospectively reviewed the records of subjects who underwent thoracic organ transplantation at our institution between January 2004 and March 2011 followed by PDT (using the Ciaglia Blue Rhino technique with direct bronchoscopic guidance). RESULTS: From a total of 312 thoracic transplant recipients, we identified 93 (29.8%) subjects with PDT. Of these, 79 had undergone double lung transplant, 11 had undergone heart transplant, 2 had undergone combined heart-lung transplant, and 1 had undergone combined heart-kidney transplant. Mean age was 49.5 ± 11.2 y, and 58% of subjects were female. The mean time from intubation to PDT was 3.7 ± 3.4 d, and mean time from transplant to PDT was 12.6 ± 28.3 d. Thirty-two subjects (34.4%) underwent PDT after re-intubation. Thirty-nine subjects were receiving renal replacement therapy (41.9%), and 28 had a coagulopathy (30.1%). Moderate but not significant bleeding was observed in 3 subjects. There were no major complications during PDT procedures. Forty-five subjects (48.4%) could be weaned successfully from the ventilator and the tracheostoma could be removed. Forty-eight subjects (51.6%) died due to sepsis, multi-organ failure, or transplant failure. No procedure-related deaths were noted. There were no significant late complications. Among the 45 who survived their stay in the ICU, the functional and cosmetic outcomes of PDT were excellent. CONCLUSIONS: PDT can be safely performed on patients with acute respiratory failure after thoracic organ transplantation. Therefore, we recommend the use of this technique for prolonged airway management in these patients.

Comparison of a New Miniaturized Extracorporeal Membrane Oxygenation System With Integrated Rotary Blood Pump to a Standard System in a Porcine Model of Acute Lung Injury.

Extracorporeal membrane oxygenation (ECMO) is used for severe acute respiratory distress syndrome. However, available ECMO systems are large and not well designed for fast delivery, emergency implantation, and interhospital transfer. Therefore, a new miniaturized oxygenator with integrated rotary blood pump (ILIAS) was developed and compared with a standard ECMO system in a large animal model. Acute lung injury was induced with repeated pulmonary saline lavage in 14 pigs until PaO2 /FiO2 -ratio was <100 mm Hg with a positive-end-expiratory-pressure of 5 mbar. Pigs were assigned to the following three groups: group 1 (n = 4): control group with conventional ventilation; group 2 (n = 5): standard vv-ECMO; group 3 (n = 5): vv-ILIAS. Gas exchange, hemodynamics, hemolysis, and coagulation activation were examined over a period of 8 h. No device failed during the observation period. PaCO2 decreased from 59.40 ± 4.14 mm Hg to 48.62 ± 4.50 mm Hg after 1 h in the ILIAS group compared with an improvement of PaCO2 from 48.86 ± 7.45 to 40.10 ± 6.02 in the conventional ECMO group (P = not significant [n.s.]). ARDS-induced respiratory acidosis was controlled promptly with a pH of 7.2 ± 0.1 at baseline increasing to 7.4 ± 0.1 in both study groups after 60 min of ECMO support. Mean carbon dioxide transfer was comparable between the conventional ECMO and ILIAS (211.36 ± 78.39 mL/min vs. 219.99 ± 76.72 mL/min, P = n.s.). PaO2 /FiO2 increased from 118.4 ± 15.5 mm Hg to 179.1 ± 72.4 mm Hg in the ILIAS group compared with an improvement of oxygenation from 107.1 ± 24.9 mm Hg to 179.0 ± 45.7 mm Hg in the standard ECMO group (P = n.s.). Mean oxygen transfer was calculated with 136.09 ± 30.25 mL/min for the ILIAS and 129.05 ± 36.28 mL/min for the standard ECMO. Hemodynamic instability or significant activation of the plasmatic coagulation was not observed. However, hemolysis was significantly higher in the ILIAS group compared with the conventional ECMO. As the ILIAS prototype provided excellent gas exchange with hemodynamic stability comparable with a standard ECMO system, we believe this study serves as a proof of concept. Further development and design modifications (optimized rotation speed and surface coating of rotor) are already done and another experiment is projected to reduce hemolysis and platelet consumption for clinical application.

A new preservation solution for lung transplantation: evaluation in a porcine transplantation model.

BACKGROUND: Lung preservation injury is still a major problem in lung transplantation. The aim of the current study was to evaluate the effects of a new preservation solution (Custodiol-N) for lung preservation. METHODS: Using an in vivo pig model, 7 lungs each were preserved for 24 hours after perfusion with: low-potassium dextran (LPD) solution as control (Group I); base solution of Custodiol-N without iron chelators (Group II); Custodiol-N (Group III); or Custodiol-N supplemented with dextran 40 (Group IV). Four animals received a sham operation. After left lung transplantation and contralateral lung exclusion, hemodynamics and blood gases were monitored for 6 hours; tissue samples were taken at the end of the experiments. RESULTS: All animals survived the transplantation procedure. Base solution- and Custodiol-N-preserved lungs (Groups II and III) showed graft function similar to that of LPD-preserved lungs (Group I), showing a trend toward improved values. Custodiol-N with dextran (Group IV) led to a significant reduction of mean pulmonary arterial pressure (20 ± 2 vs 28 ± 3 mm Hg, p < 0.01) and pulmonary vascular resistance (410 ± 51 vs 588 ± 83 dyne/s/cm(5), p < 0.01), and oxygenation ratio was significantly higher (536 ± 52 vs 313 ± 107 mm Hg at 6 hours, p < 0.01) and PCO(2) values were significantly lower (51 ± 9 vs 77 ± 5 mm Hg at 6 hours, p < 0.01) at 6 hours compared with LPD (Group I). Custodiol-N (Groups II to IV) showed a trend toward a lower wet/dry ratio and reduced oxidative stress; in the presence of dextran (Group IV), the difference was again statistically significant, when compared with LPD (Group I). CONCLUSIONS: Custodiol-N solution is a new alternative preservation solution for lung transplantation that offers significantly superior protection compared with LPD when dextran 40 is added.

Use of donors who have suffered cardiopulmonary arrest and resuscitation in lung transplantation.

OBJECTIVES: Shortage of donors is one of the major limitations in lung transplantation (LuTX) and an aggressive expansion of criteria for donor selection has been proposed. This study evaluates the outcome of recipients of pulmonary grafts coming from resuscitated donors when compared with recipients of non-resuscitated donors. METHODS: We retrospectively analyzed the donor and recipient charts of all double LuTX performed at our institution between 2000 and 2008 with regard to the performance of donor-cardiopulmonary resuscitation (CPR). RESULTS: Out of 186 eligible transplants, 22 patients (11.8%) received lungs from donors who have suffered cardiac arrest (CA) and subsequent CPR. Mean duration of CPR was 15.2 ± 11.3 min. Terminal laboratory profiles of CPR donors and non-CPR donors were similar as were ventilation time and paO(2)/FiO(2) ratio before organ harvesting or chest X-ray. CPR-donor status did not affect the following indices of graft function: length of postoperative ventilation, paO(2)/FiO(2) ratio up to 48 h and lung function up to 60 months. Length of intensive care and hospital stay, need for inotropic support and 30-day mortality were not significantly different for the transplantation of CPR or no-CPR donor lungs. One- and 3-year survival rates were comparable as well with 84.4% and 66.3% for CPR donors versus 88.5% and 69.8% no-CPR donors. CONCLUSIONS: This study indicates that transplantation of lungs from resuscitated donors may not affect outcome after LuTX. Therefore, donor history of CA should not automatically preclude LuTX.

Lung transplantation using donors 55 years and older: is it safe or just a way out of organ shortage?

OBJECTIVES: Lung organ scarcity has led to more generous acceptance of organs under the idea of extended-donor criteria. However, long-term effects have to be monitored to redefine present practice. In this study, we investigated the impact of donor age over 55 years in lung transplantation. METHODS: In this retrospective study, 186 consecutive double-lung transplantation procedures from January 2000 to December 2008 were evaluated. A total of 19 recipients received lungs from donors aged 55 years or older (range 55-69 years) (group A) and 167 received lungs from younger donors (range 8-54) (group B). In-hospital mortality, intensive care unit (ICU) stay, rejection episodes, lung function and survival up to 5 years were evaluated. RESULTS: In-hospital mortality was similar in both groups (group A: 10.5%; group B: 13.7%). Postoperative ICU stay was 19+/-33 days versus 17+/-34 days (A vs B). Rejection episodes as well as postoperative lung function up to 5 years, and overall cumulative 5-year survival (group A: 52.4%; group B: 50.9%) did not reach statistical significance. However, a trend of increased bronchiolitis obliterans syndrome (BOS) prevalence and reduced lung function was noted. Cause of death showed no differences in both groups. CONCLUSIONS: Donor age > or =55 years does not compromise immediate and long-term results after lung transplantation, although long-term observation of patients receiving such an organ suggests earlier lung dysfunction. Due to the rising need of organs, lungs from donors aged 55 or older have to be considered for transplantation. However, the acceptance should be based on donor lung evaluation and individual recipient needs. Long-term outcomes over 5 years need to be further investigated.

Improvement of pulmonary microcirculation after lung transplantation using phosphodiesterase-5 inhibitor modified preservation solution.

OBJECTIVE: Optimising the preservation modality and thus maintaining the post-transplanted organ function remains a point of interest in research in order to prevent deleterious ischaemia/reperfusion injury. Microcirculation allows the assessment of initial graft function before obvious functional parameters. It was the aim of our study to compare the effects of epoprostenol and sildenafil on the pulmonary microcirculation and haemodynamics, when used in the preservation solution in lung transplantation. METHODS: Twenty-one pigs underwent single LuTx after 24h graft-ischaemia, preserved with buffered low potassium-dextran solution (I, control); with addition of 0.66 microg/kg/bw epoprostenol (II) or with 0.15 mg/kg/bw sildenafil (III). The pulmonary microcirculation, alveolar capillary diameter (ACD), red blood cell (RBC) velocity and functional capillary density (FCD), were assessed by intravital microscopy (OPS-imaging) hourly until 6h after reperfusion. Haemodynamics and blood gas exchange were monitored at all timepoints. RESULTS: ACD was increased in group III directly after reperfusion (132+/-4.4% vs 121+/-3.1%, in % of baseline, III vs I; mean+/-SEM; p<0.05) and decreased during the experiment. RBC velocity did not reach statistical significance (256+/-93 vs 263+/-85 and 283+/-66 microm/s, III vs II and I; mean+/-SD). FCD in group III was higher than in I and II beginning 3h after reperfusion (10.1+/-1.4 vs 6.1+/-1.9 microm/microm(2), III vs I; mean+/-SEM; p<0.05). CONCLUSIONS: Our study demonstrated a significantly improved microcirculation after application of PDF V during organ procurement, probably because of better distribution of the preservation solution. Further studies are necessary, to prove the long-term effects of this observation.