Influence of preservation solution on early graft failure in clinical lung transplantation

Primary graft dysfunction following lung transplantation: From pathogenesis to future frontiers

Lung transplantation is the treatment of choice for patients with end-stage lung disease. Currently, just under 5000 lung transplants are performed worldwide annually. However, a major scourge leading to 90-d and 1-year mortality remains primary graft dysfunction. It is a spectrum of lung injury ranging from mild to severe depending on the level of hypoxaemia and lung injury post-transplant. This review aims to provide an in-depth analysis of the epidemiology, pathophysiology, risk factors, outcomes, and future frontiers involved in mitigating primary graft dysfunction. The current diagnostic criteria are examined alongside changes from the previous definition. We also highlight the issues surrounding chronic lung allograft dysfunction and identify the novel therapies available for ex-vivo lung perfusion. Although primary graft dysfunction remains a significant contributor to 90-d and 1-year mortality, ongoing research and development abreast with current technological advancements have shed some light on the issue in pursuit of future diagnostic and therapeutic tools.

Anesthetic considerations in lung transplantation: past, present and future

Lung transplantation is a very complex surgical procedure with many implications for the anesthetic care of these patients. Comprehensive preoperative evaluation is an important component of the transplant evaluation as it informs many of the decisions made perioperatively to manage these complex patients effectively and appropriately. These decisions may involve pre-emptive actions like pre-habilitation and nutrition optimization of these patients before they arrive for their transplant procedure. Appropriate airway and ventilation management of these patients needs to be performed in a manner that provides an optimal operating conditions and protection from ventilatory injury of these fragile post-transplant lungs. Pain management can be challenging and should be managed in a multi-modal fashion with or without the use of an epidural catheter while recognizing the risk of neuraxial technique in patients who will possibly be systemically anticoagulated. Complex monitoring is required for these patients involving both invasive and non-invasive including the use of transesophageal echocardiography (TEE) and continuous cardiac output monitoring. Management of the patient's hemodynamics can be challenging and involves managing the systemic and pulmonary vascular systems. Some patients may require extra-corporeal lung support as a planned part of the procedure or as a rescue technique and centers need to be proficient in instituting and managing this sophisticated method of hemodynamic support.

Procurement of lungs from brain-dead donors

Lung transplantation is the procedure of choice in many patients with end-stage lung disease and is being performed more frequently around the world. However, there continues to be shortage of donor organs with the ever-expanding number of recipients on the waiting list, leading to liberalization of the lung donor selection criteria with increasing acceptance of marginal donors while striving for excellent results. This has placed an increasing emphasis on the technique of donor lung procurement and preservation from marginal donors. Good judgment and procurement techniques are necessary to obtain high-quality donor lungs for transplantation and optimize long-term results. This is a review of our current technique used for the procurement of the lungs from brain-dead donors.

Primary Graft Dysfunction

Primary graft dysfunction (PGD) is a form of acute lung injury after transplantation characterized by hypoxemia and the development of alveolar infiltrates on chest radiograph that occurs within 72 hours of reperfusion. PGD is among the most common early complications following lung transplantation and significantly contributes to increased short-term morbidity and mortality. In addition, severe PGD has been associated with higher 90-day and 1-year mortality rates compared with absent or less severe PGD and is a significant risk factor for the subsequent development of chronic lung allograft dysfunction. The International Society for Heart and Lung Transplantation released updated consensus guidelines in 2017, defining grade 3 PGD, the most severe form, by the presence of alveolar infiltrates and a ratio of PaO₂:FiO₂ less than 200. Multiple donor-related, recipient-related, and perioperative risk factors for PGD have been identified, many of which are potentially modifiable. Consistently identified risk factors include donor tobacco and alcohol use; increased recipient body mass index; recipient history of pulmonary hypertension, sarcoidosis, or pulmonary fibrosis; single lung transplantation; and use of cardiopulmonary bypass, among others. Several cellular pathways have been implicated in the pathogenesis of PGD, thus presenting several possible therapeutic targets for preventing and treating PGD. Notably, use of ex vivo lung perfusion (EVLP) has become more widespread and offers a potential platform to safely investigate novel PGD treatments while expanding the lung donor pool. Even in the presence of significantly prolonged ischemic times, EVLP has not been associated with an increased risk for PGD.

Morbidity and mortality related to pneumonia and TRACHEOBRONCHITIS in ICU after lung transplantation

Background

Bacterial respiratory infections (BRI) are major complications contributing to increased morbidity and mortality after lung transplantation (LT). This study analyzed epidemiology and outcome of 175 consecutive patients developing BRI in ICU after LT between 2006 and 2012.

Methods

Three situations were described: colonization determined in donors and recipients, pneumonia and tracheobronchitis during the first 28 postoperative days. Severity score, demographic, bacteriologic and outcome data were collected.

Results

26% of donors and 31% of recipients were colonized. 92% of recipients developed BRI, including at least one episode of pneumonia in 19% of recipients. Only 21% of recipients developed BRI with an organism cultured from the donor’s samples, while 40% of recipients developed BRI with their own bacteria cultured before LT. Purulent sputum appears to be an important factor to discriminate tracheobronchitis from pneumonia. When compared to patients with tracheobronchitis, those with pneumonia had longer durations of mechanical ventilation (13 [3–27] vs 3 [29], p = 0.0005) and ICU stay (24 [16–34] vs 14 [9-22], p = 0.002). Pneumonia was associated with higher 28-day (11 (32%) vs 9 (7%), p = 0.0004) and one-year mortality rates (21 (61%) vs 24 (19%), p ≤ 0.0001).

Conclusions

These data confirm the high frequency of BRI right from the early postoperative period and the poor prognosis of pneumonia after LT.

Evaluation and Management of the Potential Lung Donor

The expansion of the donor lung pool has involved an evidence-driven redefinition of acceptable donors. Proceeding with transplantation with an acceptable rather than ideal donor depends on specific patient-related and organ-related risk factors as well as the severity of recipient illness. Although the physiologic optimization of brain-dead donors has not changed significantly in recent years, the use of donor management protocols has improved procurement rates. Ex vivo lung perfusion is an increasingly viable strategy to recondition lungs that would otherwise fall below the acceptable threshold for transplant. Ex vivo perfusion trials for preservation of standard donor lungs are ongoing.

Fatal invasive aspergillosis caused by Aspergillus niger after bilateral lung transplantation

Aspergillus niger is usually considered to be a low virulence fungus, not commonly reported to cause invasive infections. Invasive pulmonary aspergillosis due to Aspergillus niger was diagnosed in a 43-year-old woman following bilateral lung transplantation. Intravenous voriconazole failed to control progression of the disease. Despite salvage therapy with a combination of voriconazole and caspofungin for 23 days, the patient developed massive hemoptysis leading to death. The authors report the clinical features and treatment of this case.

STUDY ON THE PROTECTION OF ISOLATED RABBIT'S PULMONARY ISCHEMIA REPERFUSION INJURY BY ADDING TANSHINONE IIA INTO LOW POTASSIUM DEXTRAN SOLUTION

Purpose: This study investigates the protective effect of Tanshinone IIA (Tan IIA) on isolated rabbit's pulmonary ischemia reperfusion injury (IRI) and discusses its potential for the treatment of microcirculation disorders. Methods: We chose isolated rabbit's IRI as our experimental models, and randomly divided 24 New Zealand rabbits into two groups. For the control group (L), the lungs were perfused with Low Potassium Dextran (LPD) solution under 4[Formula: see text]C, and then it was preserved under 10[Formula: see text]C. For the experimental group (LT), the lungs were perfused and preserved with LPD[Formula: see text]Tan solution using the same approach. After the lungs have been preserved for 18[Formula: see text]h, we again perfused it for another 30 min. After reperfusion was completed, we determined the contents of SOD, NO, and MDA immediately. The wet to dry weight ratio (W/[Formula: see text] was then obtained. Finally, we use a combination of light microscopy and transmission electron microscopy to observe the ultra-structural changes of lung tissues. Results: We discovered that the contents of SOD and NO in group LT were higher than that in group L ([Formula: see text]). However, the MDA and the W/D values in group LT were lower than that in group L ([Formula: see text] or [Formula: see text]). We also observed that part of the tissues has hyperemia, edema, and congestion. Under the light microscopy, the structures of the pulmonary alveoli, bronchi, and capillaries were complete. But under high-power field, group L had a more obvious phenomenon of alveolar epithelium and capillary epithelium cells swelling and hypertrophy with respect to group LT. It could be observed that in the partial tissues, erythrocytes exuded from alveoli and the interval tends to widen in the alveoli. Under transmission electron microscopy, group L is observed to have mitochondria swelling, vacuolization, and even autosome edge accumulation. Microvillus of cell Type II significantly decreased or disappeared. Blood–air barrier swelled severely and a portion of it was cracked. The phenomena above were obviously reduced for group LT. Conclusion: Our experiments confirmed that adding Tan IIA into LPD solution can reduce the isolated rabbit's IRI effectively.

Risk factors and outcome of primary graft dysfunction after lung transplantation in Korea

BACKGROUND

Primary graft dysfunction (PGD) is a severe, acute and post-transplantation lung injury associated with early morbidity and mortality. We aimed to identify clinical risk factors for PGD, as well as the outcome of PGD after lung transplantation in Korea.

METHODS

We retrospectively analyzed lung transplant patients in a South Korean Hospital. The primary outcome was grade 3 PGD, defined according to the International Society for Heart and Lung Transplantation criteria. We compared grade 0-2 PGD group to grade 3 PGD group to identify the risk factors and outcome of grade 3 PGD.

RESULTS

Sixty-one patients were enrolled; 16 (26.2%) developed grade 3 PGD. Univariate analysis revealed higher body mass index (BMI) and history of smoking, extracorporeal membrane oxygenation (ECMO) before transplantation in recipients, and an extended intraoperative ischemic time as risk factors for grade 3 PGD. In multivariate analysis, independent risk factors for PGD were higher BMI in recipients [odds ratio (OR), 1.286; P=0.043] and total intraoperative ischemic time (OR, 1.028; P=0.007). As compared to grade 0-2 PGD, grade 3 PGD was significantly associated with a higher re-operation rate (grade 0-2 PGD vs. grade 3 PGD, 22.2% vs. 50.0%; P=0.036), prolonged ventilator apply (median: 6.0 vs. 14.5 days; P=0.044), a longer intensive care unit stay (median: 9.0 vs. 17.0 days; P=0.041), and a higher rate of renal replacement therapy (RRT) (17.8% vs. 62.5%; P=0.002) after transplantation.

CONCLUSIONS

Patients who developed grade 3 PGD had higher re-operation rate, longer ventilator apply, longer intensive care unit stay, higher rate of RRT, with higher BMI and total intraoperative ischemic time being the significant risk factor. These findings may allow physicians to modify risk factors before development of PGD.

Onset of Inflammation With Ischemia: Implications for Donor Lung Preservation and Transplant Survival

Lungs stored ahead of transplant surgery experience ischemia. Pulmonary ischemia differs from ischemia in the systemic organs in that stop of blood flow in the lung leads to loss of shear alone because the lung parenchyma does not rely on blood flow for its cellular oxygen requirements. Our earlier studies on the ischemia-induced mechanosignaling cascade showed that the pulmonary endothelium responds to stop of flow by production of reactive oxygen species (ROS). We hypothesized that ROS produced in this way led to induction of proinflammatory mediators. In this study, we used lungs or cells subjected to various periods of storage and evaluated the induction of several proinflammatory mediators. Isolated murine, porcine and human lungs in situ showed increased expression of cellular adhesion molecules; the damage-associated molecular pattern protein high-mobility group box 1 and the corresponding pattern recognition receptor, called the receptor for advanced glycation end products; and induction stabilization and translocation of hypoxia-inducible factor 1α and its downstream effector VEGFA, all of which are participants in inflammation. We concluded that signaling with lung preservation drives expression of inflammatory mediators that potentially predispose the donor lung to an inflammatory response after transplant.

Shear stress-related mechanosignaling with lung ischemia: lessons from basic research can inform lung transplantation

Cessation of blood flow represents a physical event that is sensed by the pulmonary endothelium leading to a signaling cascade that has been termed "mechanotransduction." This paradigm has clinical relevance for conditions such as pulmonary embolism, lung bypass surgery, and organ procurement and storage during lung transplantation. On the basis of our findings with stop of flow, we postulate that normal blood flow is "sensed" by the endothelium by virtue of its location at the interface of the blood and vessel wall and that this signal is necessary to maintain the endothelial cell membrane potential. Stop of flow is sensed by a "mechanosome" consisting of PECAM-VEGF receptor-VE cadherin that is located in the endothelial cell caveolae. Activation of the mechanosome results in endothelial cell membrane depolarization that in turn leads to activation of NADPH oxidase (NOX2) to generate reactive oxygen species (ROS). Endothelial depolarization additionally results in opening of T-type voltage-gated Ca(2+) channels, increased intracellular Ca(2+), and activation of nitric oxide (NO) synthase with resultant generation of NO. Increased NO causes vasodilatation whereas ROS provide a signal for neovascularization; however, with lung transplantation overproduction of ROS and NO can cause oxidative injury and/or activation of proteins that drive inflammation and cell death. Understanding the key events in the mechanosignaling cascade has important lessons for the design of strategies or interventions that may reduce injury during storage of donor lungs with the goal to increase the availability of lungs suitable for donation and thus improving access to lung transplantation.

Preservation solutions for cardiac and pulmonary donor grafts: a review of the current literature

Hypothermic preservation of donor grafts is imperative to ameliorate ischemia related cellular damage prior to organ transplantation. Numerous solutions are in existence with widespread variability among transplant centers as to a consensus regarding the optimal preservation solution. Here, we present a concise review of pertinent preservation studies involving cardiac and pulmonary allografts in an attempt to minimize the variability among institutions and potentially improve graft and patient survival. A biochemical comparison of common preservation solutions was undertaken with an emphasis on Euro Collins (EC), University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK), Celsior (CEL), Perfadex (PER), Papworth, and Plegisol. An appraisal of the literature ensued containing the aforementioned preservation solutions in the setting of cardiac and pulmonary transplantation. Available evidence supports UW solution as the preservation solution of choice for cardiac transplants with encouraging outcomes relative to notable contenders such as CEL. Despite its success in the setting of cardiac transplantation, its use in pulmonary transplantation remains suboptimal and improved outcomes may be seen with PER. Together, we suggest, based on the literature that the use of UW solution and PER for cardiac and pulmonary transplants, respectively may improve transplant outcomes such as graft and patient survival.

Initial topical cooling followed by backtable Celsior flush perfusion provides excellent early graft function in porcine single lung transplantation after 24 hours of cold ischemia

BACKGROUND

Topical in situ cooling of the donor lungs is a prerequisite for procurement of non-heart-beating donor lungs and may be of interest for living related lung donation.

METHODS

Twenty-four single lung transplants were performed in 4 groups of Landrace pigs (6 per group). Control LPD, control Celsior and topical cooling in situ, followed by LPD (exLPD) or Celsior (exCel) ex situ flush, were employed. All lungs were perfused antegrade with 1 liter of solution at 4°C. Lungs were stored immersed in preservation solution for 24 hours at 4°C. After transplantation of the left lung, the right recipient bronchus and pulmonary artery were clamped.

RESULTS

Four of 6 animals each in the LPD and Celsior groups and all 6 animals in both the exLPD and the exCel groups survived the 7-hour reperfusion. The mean oxygenation index was favorably preserved in the exCel group at 7 hours after reperfusion (417 ± 81) over all other groups (LPD 341 ± 133, Celsior 387 ± 86, exLPD 327 ± 76; p < 0.0001). Pulmonary vascular resistance showed significantly lower values in the Celsior and exCel groups (LPD 1,310 ± 620, Celsior 584 ± 194, exLPD 1,035 ± 361, exCel 650 ± 116 dyn/s/cm(5) at 7 hours after reperfusion; p < 0.0001). Consistently, the wet-to-dry lung weight ratio also indicated beneficial graft protection in the exCel group (LPD 8.1 ± 0.8, Celsior 8.4 ± 0.8, exLPD 7.5 ± 1.0, exCel 3.1 ± 0.9; p < 0.0001).

CONCLUSION

Initial topical cooling followed by backtable perfusion is a sufficient technique for pulmonary graft preservation providing excellent post-transplant function. Celsior subsequent to in-situ topical cooling revealed the most beneficial results in this setting. This combined technique could advance non-heart-beating, living related lung lobe donation and, potentially, regular heart-beating lung donation.

Donor management and lung preservation for lung transplantation

Although lung transplantation has become a life-saving option for patients with end-stage lung disease, this intervention is hampered by a shortage of lungs in view of the growing number of people on the waiting list. Lungs are retrieved from only a small percentage of multiorgan donors, and the transplantation and intensive-care communities have recognised the need to develop innovative methods to expand the donor pool. Advancements in lung-preservation techniques in the preretrieval and postretrieval periods have increased the pool of available donors, and novel research and discoveries in this area have steadily improved post-transplantation adverse events. This Review summarises current best practice and the latest research on intensive-care management of a potential lung donor. We also discuss lung-preservation techniques, including advancements in normothermic ex-vivo lung perfusion, and the potential for a personalised medicine approach to the organ.

Comparative impact on islet isolation and transplant outcome of the preservation solutions Institut Georges Lopez-1, University of Wisconsin, and Celsior

BACKGROUND

Institut Georges Lopez-1 (IGL-1) is a preservation solution similar to University of Wisconsin (UW) with reversed Na/K contents. In this study, we assessed the impact of IGL-1, UW, and Celsior (CS) solutions on islet isolation and transplant outcome.

METHODS

We retrospectively analyzed 376 islet isolations from pancreases flushed and transported with IGL-1 (n=95), UW (n=204), or CS (n=77). We determined isolation outcome and β-cell function in vitro. Transplanted patients were divided into three groups depending on preservation solution of pancreas, and islet graft function was assessed by decrease in daily insulin needs, C-peptide/glucose ratios, β-scores, and transplant estimated function at 1- and 6-month follow-up.

RESULTS

IGL-1, UW, and CS groups were similar according to donor age, body mass index, and pancreas weight. There was no difference in islet yields between the three groups. Success rates, transplant rates, β-cell secretory function, and viability were similar for all three groups. We observed no difference in decreased insulin needs, C-peptide glucose ratios, β-scores, and transplant estimated function at 1- and 6-month follow-up between IGL-1, UW, and CS groups.

CONCLUSIONS

Our study shows that IGL-1 is equivalent to UW or CS solutions for pancreas perfusion and cold storage before islet isolation and transplantation.

Celsior versus University of Wisconsin preserving solutions for liver transplantation: postreperfusion syndrome and outcome of a 5-year prospective randomized controlled study

BACKGROUND

Celsior solution (CS) is a high-sodium, low-potassium, low-viscosity extracellular solution that has been used for liver graft preservation in recent years, although experience with it is still limited. We performed an open-label randomized active-controlled trial comparing CS with the University of Wisconsin solution (UW) for liver transplantation (LT), with a follow-up period of 5 years.

METHODS

Adult transplant recipients (n=102) were prospectively randomized to receive either CS (n=51) or UW (n=51). The two groups were comparable with respect to donor and recipient characteristics. The primary outcome measure was the incidence of postreperfusion syndrome (PRS). Secondary outcome measures included primary nonfunction (PNF) or primary dysfunction (PDF), liver retransplantation, and graft and patient survival. Other secondary outcome measures were days in the intensive care unit (ICU) and the rates of acute rejection, chronic rejection, infectious complications, postoperative reoperations, and vascular and biliary complications.

RESULTS

In all, 14 posttransplant variables revealed no significant differences between the groups. There were no cases of PNF or PDF. The incidence of PRS was 5.9% in the CS group and 21.6% in the UW group (P=0.041). After reperfusion, CS revealed greater control of serum potassium (P=0.015), magnesium levels (P=0.005), and plasma glucose (P=0.042) than UW. Respective patient survivals at 3, 12, and 60 months were 95.7, 87.2, and 82.0% for the CS group and 95.7, 83.3, and 66.6% for the UW group (P=0.123).

CONCLUSIONS

While retaining the same degree of safety and effectiveness as UW for LT, CS may yield postliver graft reperfusion benefits, as shown in this study by a significant reduction in the incidence of PRS and greater metabolic control.

Optimizing post-transplant outcomes in lung transplantation

Lung transplant recipients are at risk of numerous complications, which range from early events, such as primary graft dysfunction, to late events, including opportunistic infection or graft loss caused by chronic rejection. Although lung transplantation is often the only therapeutic option that can improve quality of life and prolong survival for many forms of end-stage lung disease, survival following lung transplantation is significantly worse than survival following transplantation of other solid organs. Carefully choosing potential recipients for listing, maximizing the likelihood that donor organs will function well following implantation, appropriate use of immunosuppressive agents to prevent allograft rejection, prophylactic or pre-emptive strategies to prevent allograft infection and appropriate surveillance to detect significant complications are key to maximizing the likelihood of prolonged graft and patient survival while avoiding significant complications following lung transplantation. Post-transplant outcomes will be optimized by a team approach to comprehensive management of the lung transplantation recipient combined with vigilant surveillance to detect complications in a timely fashion.

Preservation solution for lung transplantation

Despite the increasing success of lung transplantation as the mainstay therapeutic modality for end-stage lung disease, the 1-year survival rate after lung transplantation remains 80% and primary graft dysfunction (PGD) accounts for 30% of mortality. Ischemia-reperfusion injury has been identified as one of the main causes of PGD, and thus significant efforts have been made to optimize the methods for lung preservation in an attempt to minimize lung injury during the period of ischemia. The composition of the lung preservation solution used in the pulmonary artery flush has been considered to be the key to successful lung preservation, and many lung transplant programs have been shifting the use of the preservation solution from the intracellular fluid type to the extracellular fluid type because of preferable posttransplant lung function with the latter. This review summarizes the experimental and clinical studies on lung preservation, particularly focusing attention on the preservation solution being employed for clinical lung transplantation.

[Early postoperative management and immunosuppressive treatment following lung transplantation]

Lung transplantation is now considered a valid option in the management of end-stage respiratory failure. The postoperative period remains a key stage that will influence the average long-term prognosis of the patients. Primary graft failure, postoperative bleeding, infection, acute rejection and complications linked to the surgery, and to vascular or bronchial anastomoses, are risk factors for mortality and morbidity. These must be taken care of quickly via collaboration with the surgical team. The immunosuppressive treatment essential for tolerance induction with regard to the transplanted organ will be introduced during the intraoperative period and continued for life. The combination of a calcineurin inhibitor, an antiproliferative agent and corticosteroids remains the conventional procedure. The role of new molecules as mTor inhibitors remains to be determined.

Low pulmonary artery flush perfusion pressure combined with high positive end-expiratory pressure reduces oedema formation in isolated porcine lungs

Flush perfusion of the pulmonary artery with organ protection solution is a standard procedure before lung explantation. However, rapid flush perfusion may cause pulmonary oedema which is deleterious in the lung transplantation setting. In this study we tested the hypotheses that high pulmonary perfusion pressure contributes to the development of pulmonary oedema and positive end-expiratory pressure (PEEP) counteracts oedema formation. We expected oedema formation to increase weight and decrease compliance of the lungs on the basis of a decrease in alveolar volume as fluid replaces alveolar air spaces. The pulmonary artery of 28 isolated porcine lungs was perfused with a low-potassium dextrane solution at low (mean 27 mmHg) or high (mean 40 mmHg) pulmonary artery pressure (PAP) during mechanical ventilation at low (4 cmH(2)O) or high (8 cmH(2)O) PEEP, respectively. Following perfusion and storage, relative increases in lung weight were smaller (p < 0.05) during perfusion at low PAP (62 +/- 32% and 42 +/- 26%, respectively) compared to perfusion at high PAP (133 +/- 54% and 87 +/- 30%, respectively). Compared to all other PAP-PEEP combinations, increases in lung weight were smallest (44 +/- 9% and 27 +/- 12%, respectively), nonlinear intratidal lung compliance was largest (46% and 17% respectively, both p < 0.05) and lung histology showed least infiltration of mononuclear cells in the alveolar septa, and least alveolar destruction during the combination of low perfusion pressure and high PEEP. The findings suggest that oedema formation during pulmonary artery flush perfusion in isolated and ventilated lungs can be reduced by choosing low perfusion pressure and high PEEP. PAP-PEEP titration to minimize pulmonary oedema should be based on lung mechanics and PAP monitoring.

Risk factors for early primary graft dysfunction after lung transplantation: a registry study

BACKGROUND

Primary graft dysfunction (PGD) is a leading cause of early morbidity and mortality in lung transplantation. We sought to identify risk factors for PGD using the United Network for Organ Sharing/International Society for Heart and Lung Transplant (UNOS/ISHLT) Registry.

METHODS

A total of 6984 lung transplants between 1994 and 2002 were available for analysis. Potential risk factors were tested for association with PGD and multivariable logistic regression was applied to adjust for confounding.

RESULTS

The overall incidence of PGD was 10.7% (95% CI 9.9-11.4). In multivariable analyses, factors independently associated with PGD were donor age >45 yr (p < 0.001); donor head trauma (p = 0.03); recipient body mass index >25 kg/m(2) (p = 0.005); recipient female gender (p = 0.001); use of Eurocollins preservation solution (p = 0.001); single lung transplant (p = 0.005); increased ischemic time (p < 0.001); and elevated recipient pulmonary artery systolic pressure at transplant (p < 0.001). Recipient transplant diagnosis was strongly associated with PGD, with primary or secondary pulmonary hypertension (p < 0.001 for both), and idiopathic (p < 0.001) or secondary pulmonary fibrosis (p = 0.011) as significant and independent risk factors for PGD.

CONCLUSIONS

Risk factors for PGD in the UNOS/ISHLT registry are consistent with prior smaller studies. Recipient, donor, and therapy variables are independently associated with PGD, as defined in a large registry.

Pancreas preservation for pancreas and islet transplantation

PURPOSE OF REVIEW

To summarize advances and limitations in pancreas procurement and preservation for pancreas and islet transplantation, and review advances in islet protection and preservation.

RECENT FINDINGS

Pancreases procured after cardiac death, with in-situ regional organ cooling, have been successfully used for islet transplantation. Colloid-free Celsior and histidine-tryptophan-ketoglutarate preservation solutions are comparable to University of Wisconsin solution when used for cold storage before pancreas transplantation. Colloid-free preservation solutions are inferior to University of Wisconsin solution for pancreas preservation prior to islet isolation and transplantation. Clinical reports on pancreas transplants suggest that the two-layer method may not offer significant benefits over cold storage with the University of Wisconsin solution: improved oxygenation may depend on the graft size; benefits in experimental models may not translate to human organs. Improvements in islet yield and quality occurred from pancreases treated with inhibitors of stress-induced apoptosis during procurement, storage, isolation or culture desirable before islet isolation and transplantation and may improve islet yield and quality. Methods for real-time, noninvasive assessment of pancreas quality during preservation have been implemented and objective islet-potency assays have been developed and validated. These innovations should contribute to objective evaluation and establishment of improved pancreas-preservation and islet-isolation strategies.

SUMMARY

Cold storage may be adequate for preservation before pancreas transplants, but insufficient when pancreases are processed for islets or when expanded donors are used. Supplementation of cold-storage solutions with cytoprotective agents and perfusion may improve pancreas and islet transplant outcomes.

Anti-type V collagen humoral immunity in lung transplant primary graft dysfunction

Primary graft dysfunction (PGD) is a major complication following lung transplantation. We reported that anti-type V collagen (col(V)) T cell immunity was strongly associated with PGD. However, the role of preformed anti-col(V) Abs and their potential target in PGD are unknown. Col(V) immune serum, purified IgG or B cells from col(V) immune rats were transferred to WKY rat lung isograft recipients followed by assessments of lung pathology, cytokines, and PaO(2)/FiO(2), an index of lung dysfunction in PGD. Immune serum, purified IgG, and B cells all induced pathology consistent with PGD within 4 days posttransfer; up-regulated IFN-gamma, TNF-alpha, and IL-1beta locally; and induced significant reductions in PaO(2)/FiO(2). Depleting anti-col(V) Abs before transfer demonstrated that IgG2c was a major subtype mediating injury. Confocal microscopy revealed strong apical col(V) expression on lung epithelial, but not endothelial cells; which was consistent with the ability of col(V) immune serum to induce complement-dependent cytotoxicity only in the epithelial cells. Examination of plasma from patients with or without PGD revealed that higher levels of preformed anti-col(V) Abs were strongly associated with PGD development. This study demonstrates a major role for anti-col(V) humoral immunity in PGD, and identifies the airway epithelium as a target in PGD.

Pancreas preservation for pancreas and islet transplantation

PURPOSE OF REVIEW

To summarize advances and limitations in pancreas procurement and preservation for pancreas and islet transplantation, and review advances in islet protection and preservation.

RECENT FINDINGS

Pancreases procured after cardiac death, with in-situ regional organ cooling, have been successfully used for islet transplantation. Colloid-free Celsior and histidine-tryptophan-ketoglutarate preservation solutions are comparable to University of Wisconsin solution when used for cold storage before pancreas transplantation. Colloid-free preservation solutions are inferior to University of Wisconsin solution for pancreas preservation prior to islet isolation and transplantation. Clinical reports on pancreas and islet transplants suggest that the two-layer method may not offer significant benefits over cold storage with the University of Wisconsin solution: improved oxygenation may depend on the graft size; benefits in experimental models may not translate to human organs. Improvements in islet yield and quality occurred from pancreases treated with inhibitors of stress-induced apoptosis during procurement, storage, isolation or culture. Pancreas perfusion may be desirable before islet isolation and transplantation and may improve islet yields and quality. Methods for real-time, noninvasive assessment of pancreas quality during preservation have been implemented and objective islet potency assays have been developed and validated. These innovations should contribute to objective evaluation and establishment of improved pancreas preservation and islet isolation strategies.

SUMMARY

Cold storage may be adequate for preservation before pancreas transplants, but insufficient when pancreases are processed for islets or when expanded donors are used. Supplementation of cold storage solutions with cytoprotective agents and perfusion may improve pancreas and islet transplant outcomes.

[Solutions for organ preservation and other cardioplegic liquid formulations. Role of the hospital pharmacist]

Solid organ transplantation is an increasing need and a well-established activity which requires maintaining the quality of the transplant from procurement through the entire, storage, transport and graft procedure. Solutions for organ preservation play a key role in this procedure, by minimizing the deleterious effects of both ischemia and reperfusion. As such, their qualitative and quantitative compositions have to be optimized and validated. The development strategy and formulations proposed for these solutions are analyzed in this review as well as the results of the clinical studies which have set up the relevant pharmacological and physicochemical criteria. The French regulatory status of these products is also discussed. A clear distinction has to be made between solutions for organ preservation which are classified as produits thérapeutiques annexes (therapeutic ancillary products) and cardioplegic liquid formulations which are considered as medicinal products and are subject to marketing approval. Finally, the roles of the hospital pharmacist in the evaluation, selection, purchase and proper use of these products are described.

Does the method of lung preservation influence outcome after transplantation? An analysis of 681 consecutive procedures

OBJECTIVE

Despite 50 years of lung preservation research, the optimal preservation technique is undefined. Using data from a national cohort, we investigated outcomes with different preservation methods after adult lung transplantation.

METHODS

Early (30-day), late (30-day to 3-year), and overall (3-year) mortalities, adjusted for differences in donor and recipient characteristics, were compared by using Cox regression. Intensive care unit length of stay and the number of rejection episodes were secondary outcomes.

RESULTS

Six hundred eighty-one eligible lung transplantations between July 1995 and June 2003 were preserved with Euro-Collins solution (n = 284), blood albumin (n = 139), core cooling (n = 107), or low potassium dextran solution (n = 151). There was significantly increased use of low potassium dextran solution over time (P < .001). Unadjusted 3-year survival was similar across the groups (P = .72), with the highest 3-year survival in the low potassium dextran group (62%; 95% confidence interval, 51%-72%) and the lowest in the blood albumin group (49%; 95% confidence interval, 39%-58%). Risk-adjusted early (P = .70), late (P = .27), and overall (P = .72) survival was similar across the groups and was not affected by ischemic time. Freedom from death caused by primary graft dysfunction was again highest in the low potassium dextran group (95%; 95% confidence interval, 90%-98%) and lowest in the blood albumin group (91%; 95% confidence interval, 85%-95%). There was no difference in intensive care unit length of stay. An increased incidence of rejection was apparent with increasing ischemic time (P = .067).

CONCLUSION

The methods of lung preservation in current use do not seem to affect early or midterm survival after transplantation, but increasing ischemic time might predispose to increased rejection.

Pancreas preservation with the University of Wisconsin versus Celsior solutions

INTRODUCTION

The use of Celsior solution for organ preservation has not been thoroughly studied in pancreas transplantation. The aim of this study was to compare University of Wisconsin and Celsior solutions for preservation of pancreas grafts.

PATIENTS AND METHODS

From March 1995 to December 2005, 72 patients with type 1 diabetes underwent pancreas transplantation. There were 42 men and 30 women, with a mean age at transplantation of 38.1 +/- 7.5 years (range: 27 to 55 years), and a mean duration of diabetes of 22.5 +/- 6.6 years. Recipients were classified into two groups according to the preservation solution: (A) Celsior (n = 28, 38.9%) and (B) Wisconsin (n = 44, 61.1%).

RESULTS

The donor and recipient characteristics were similar in both groups. There were five cases of venous thrombosis in the Wisconsin group and two in the Celsior group (P = NS). The venous drainage technique in the former group was portocaval in 19 patients and portoiliac in 25; in the Celsior group, portocaval in 23 patients and portoiliac in five (P = .001). Enteric drainage was used in 19 patients from the Celsior group and 17 patients from the Wisconsin group (P = .01). Actuarial 2-year graft survival was 74.6% in the Wisconsin group and 77.4% in the Celsior group (P = NS).

CONCLUSIONS

No differences were observed in venous thrombosis between the two groups. The lower rate of venous thrombosis with the portocaval technique was related to the type of venous drainage rather than the type of preservation solution. Celsior solution may be considered as good as Wisconsin solution for pancreas transplantation.

Early outcomes comparing Perfadex, Euro-Collins, and Papworth solutions in lung transplantation

BACKGROUND

Despite improved surgical techniques and medical management, primary graft dysfunction (PGD) remains a major cause of early morbidity and mortality after lung transplantation. Different types of lung preservation solutions have been developed and applied to clinical use; however, the relative clinical efficacy of these solutions to prevent PGD remains controversial. This study aimed to investigate the effect of the three solutions most commonly used (Perfadex [Vitrolife, Göteborg, Sweden], Papworth, and Euro-Collins [Baxter Healthcare, Old Toongabbie NSW, Australia]) on posttransplant outcomes.

METHODS

Early outcomes from 157 consecutive lung transplants (113 bilateral and 44 single) performed at The Alfred Hospital were compared across three preservation solutions.

RESULTS

Posttransplant oxygenation (p = 0.57), pulmonary vascular resistance (p = 0.34), intubation hours (p = 0.66), intensive care unit days (p = 0.34), severe PGD (grade 3) (p = 0.70), 30-day mortality (p = 0.87), and 3-month % predicted forced expiratory volume in 1 second (p = 0.58) were not statistically different; however, Perfadex trended toward superiority among the three solutions. After adjustment of donor, recipient, and operative factors in multivariate analysis, Perfadex was significantly associated with the prevention of moderate to severe PGD (grade 2 to 3) at 48 hours posttransplant (odds ratio = 0.26 [0.10 to 0.72], p < 0.01) compared with Papworth (odds ratio = 0.75 [0.32 to 1.75], p = 0.51) and Euro-Collins (reference) solutions.

CONCLUSIONS

Although any advantageous effects of Perfadex on early posttransplant outcomes were generally subtle and statistically nonsignificant, Perfadex prevented moderate to severe PGD. Switching preservation solution from Euro-Collins (or Papworth) to Perfadex would appear to usefully contribute to a strategy to reduce PGD in lung transplantation.

Risk factors for reperfusion injury after lung transplantation

OBJECTIVE

To assess the influence of recipient's and donor's factors as well as surgical events on the occurrence of reperfusion injury after lung transplantation.

DESIGN AND SETTING

Retrospective study in the surgical intensive care unit (ICU) of a university hospital.

METHODS

We collected data on 60 lung transplantation donor/recipient pairs from June 1993 to May 2001, and compared the demographic, peri- and postoperative variables of patients who experienced reperfusion injury (35%) and those who did not.

RESULTS

The occurrence of high systolic pulmonary pressure immediately after transplantation and/or its persistence during the first 48 h after surgery was associated with reperfusion injury, independently of preoperative values. Reperfusion injury was associated with difficult hemostasis during transplantation (p=0.03). Patients with reperfusion injury were more likely to require the administration of catecholamine during the first 48 h after surgery (p=0.014). The extubation was delayed (p=0.03) and the relative odds of ICU mortality were significantly greater (OR 4.8, 95% CI: 1.06, 21.8) in patients with reperfusion injury. Our analysis confirmed that preexisting pulmonary hypertension increased the incidence of reperfusion injury (p<0.01).

CONCLUSIONS

Difficulties in perioperative hemostasis were associated with reperfusion injury. Occurrence of reperfusion injury was associated with postoperative systolic pulmonary hypertension, longer mechanical ventilation and higher mortality. Whether early recognition and treatment of pulmonary hypertension during transplantation can prevent the occurrence of reperfusion injury needs to be investigated.

A Comparison of Cold Storage Solutions for Pancreas Preservation Prior to Islet Isolation

BACKGROUND

Several solutions are used to preserve the pancreas prior to islet isolation. This study sought to assess whether the type of solution had an impact on the isolation outcome.

METHODS

We reviewed data from 125 islet isolation procedures performed from January 2002 to January 2005. Pancreata were preserved in University of Wisconsin (UW) (n = 101), Celsior (CS) (n = 19), or IGL-1 (n = 5) solutions. Islet isolation results and transplantation rates were compared between groups.

RESULTS

UW, CS, and IGL-1 groups were similar according to donor's age, weight, and body mass index. Weight of undigested pancreas was 20 +/- 13.1, 21.4 +/- 15.7, and 17.4 +/- 8.7 g for UW, CS, and IGL-1, respectively (P > .2). Final total number of IEQ was 267,000 +/- 132,000, 277,000 +/- 155,000, and 311,000 +/- 163,000, respectively (P > .4). Success rate (defined as >250,000 IEQ) was 55.5%, 52.9%, and 60% for UW, Celsior, and IGL-1 (P > .9); the transplantation rate was 42.2% for UW, 36.8% for Celsior, and 80% for IGL-1 preservation (P > .2).

CONCLUSIONS

In this preliminary study, UW, Celsior, and IGL-1 solutions demonstrated similar islet isolation results. The new IGL-1 solution appears promising.

Influence of Donor Characteristics on Outcome After Lung Transplantation: A Multicenter Study

BACKGROUND

The liberalization of lung-donor criteria and the use of marginal donors have been advocated to face the current shortage of donors in lung transplantation. However, the impact of donor characteristics on the outcome of lung transplantation is still largely unknown. We aimed to determine, on a large cohort of patients, the effect of donors characteristics on short- and long-term outcome of lung transplantation

METHODS

Between 1988 and 1998, a total of 785 adult patients underwent single-lung transplantation (n = 270), bilateral-lung transplantation (n = 251), and heart-lung transplantation (n = 264) in 7 centers in France. We constructed several multivariate models to assess the relationship between donor characteristics and early gas exchange, duration of mechanical ventilation, and long-term survival after lung transplantation.

RESULTS

Among donor characteristics, donor gas exchange before harvest was found to be significantly associated with recipient early gas exchange, duration of mechanical ventilation, and long-term survival after adjustment for potential confounding variables. Moreover, nonlinear modeling showed a steep increase in the relative risk of death when donor PaO2/FiO2 before harvest was below 350 (hazard ratio 1.43; 95% confidence interval 1.10-1.85; p = 0.01). Donor and recipient sex mismatch were also found to be significantly associated with long-term survival.

CONCLUSIONS

Although liberalization of lung-donor criteria may be considered to overcome the shortage of lung donors, our data suggest that the violation of the gas-exchange criterion should be avoided.

Experimental Lung Transplantation: Impact of Preservation Solution and Route of Delivery

BACKGROUND

Optimal preservation of allograft integrity is essential to reduce post-ischemic organ dysfunction after lung transplantation. Retrograde organ preservation leads to homogeneous intrapulmonary distribution and eliminates intravascular thrombi. So far, no comparative studies exist with regard to preservation quality following retrograde preservation with Perfadex and Celsior after extended cold-ischemia intervals.

METHODS

In an in vivo pig model, 5 lungs each were preserved for 27 hours using antegrade or retrograde perfusion techniques with Celsior (Ce(ant)/CE(ret)) and Perfadex (PER(ant)/PER(ret)). After left lung transplantation and contralateral lung exclusion, hemodynamics, oxygenation and dynamic compliance were monitored for 6 hours and compared with sham-operated controls. Pulmonary edema was determined stereologically. Statistics consisted of analysis of variance (ANOVA) with repeated measures.

RESULTS

Mortality of all Celsior-protected lungs was 100% due to severe reperfusion injury with profound lung edema. In contrast, organ preservation with PER(ant) led to sufficient graft function without mortality. Preservation quality after retrograde administration of Perfadex resulted in optimized oxygenation capacity compared with PER(ant) (p = 0.046). Furthermore, intra-alveolar edema was reduced and generally comparable with sham controls. In general, retrograde preservation led to continuous washout of small blood and fibrin clots from the pulmonary capillary system.

CONCLUSIONS

Perfadex solution provided sufficient lung preservation for 27 hours of cold ischemia, and its retrograde application led to significant functional and histologic improvement compared with antegrade perfusion. In contrast, preservation with Celsior solution resulted in lethal post-ischemic outcome, regardless of the route of administration, and therefore must be considered unsuitable for extended lung procurement.