Search

In this review, we discuss the current state of donation after circulatory death (DCD). We define the DCD donor and describe the current protocols in management of the DCD patient. We then discuss current techniques in organ procurement of the lung and abdominal organs.Although donation after brain death is preferable to DCD, recent data have demonstrated acceptable early outcomes in both thoracic and abdominal organ transplant. In spite of advancements in surgical techniques and organ preservation, much has yet to be learned to minimize warm ischemia time and reperfusion injury in the DCD population.In light of the continually growing disparity between organ supply and demand, DCD has regained traction as a means to increase the donor pool.

OBJECTIVE To estimate the rates of early neonatal and maternal complications in a consecutive series of successful Kielland's rotational forceps deliveries. METHODS This was a retrospective cohort study of consecutive cases of successful rotational forceps deliveries performed in singleton pregnancies at 36 weeks of gestation or more in a tertiary referral center in Scotland, UK, from 2001 to 2008 (n=873). We also compared outcomes associated with successful rotational forceps deliveries in 2008 (n=150) with those of nonrotational forceps delivery (n=873), ventouse delivery (n=159), spontaneous vertex delivery (n=3,494), and emergency cesarean delivery (n=947). RESULTS There was one stillbirth associated with a rotational forceps delivery. This was diagnosed before application of forceps. After rotational forceps deliveries, 58 of 872 (6.7%) of live-born neonates were admitted to the neonatal unit. Twenty-seven of 872 (3.1%) neonates had one or more complications that could be attributable to traumatic delivery and seven neonates (0.8%) had a diagnosis of neonatal encephalopathy. When compared with alternative methods of delivery over a single year, neonatal admission rates after delivery by rotational forceps deliveries (5 of 150 [3.3%]) were not significantly different from spontaneous vertex delivery (128 of 3,494 [3.7%; P=1.00]) or ventouse delivery (6 of 159 [3.8%; P=1.00]) and lower than emergency cesarean delivery (106 of 947 [11.2%; P=.002). Postpartum hemorrhage rates after rotational forceps deliveries (8 of 150 [5.3%; P=.008]) were lower than those associated with emergency cesarean delivery (142 of 947 [15.0%; P=.008]). CONCLUSION Rates of short-term neonatal and maternal complications after successful rotational forceps deliveries are low. LEVEL OF EVIDENCE II.

The prevalence of gastroesophageal reflux disease (GERD) in lung transplant patients is twice that of the general population, yet it is unclear which pathophysiological factors play a role in the development or exacerbation of GERD in these patients.1–4 It has been speculated that the lung transplantation itself might be causative in the pathogenesis of GERD after lung transplantation, probably by increasing the risk of esophageal or vagal nerve injury or by increasing the transdiaphragmatic gastroesophageal pressure gradient.1,2 For example, Young et al2 demonstrated that GERD worsens after lung transplantation, reporting that the mean esophageal acid contact time in the supine position before and after transplant doubled from 5.1% to 11.4%. However, they failed to demonstrate that the type of transplant may be responsible for the deterioration of the reflux profile in these patients. Conversely, in a small study that we conducted to determine the prevalence and extent of GERD, as well as the frequency of risk factors and complications of GERD in lung transplant patients, we incidentally found that GERD was more common after bilateral transplantation and retransplantation than after a unilateral lung transplant.1 Therefore, to understand if the type of transplant may lead more frequently to GERD and proximal reflux, we have investigated the prevalence of distal and proximal reflux, as well as the radiologic, endoscopic, and manometric characteristics, in a much larger series of lung transplant patients, which have been stratified according to the type of transplant received (unilateral, bilateral, or retransplant).

Lung transplantation is now a well established treatment option for several end-stage respiratory diseases. Survival after lung transplantation has significantly improved over the last decade. The primary limitation to increased utilization of lung transplantation remains donor scarcity. Suitable allografts have been procured from donors after determination of neurologic death and from donors after determination of cardiac death (DDCD or DCD). Historically, the first human lung transplantation performed, utilized an allograft procured after cardiovascular death, also referred to as nonheart-beating donor.The experience at University of Wisconsin in 1993 reintroduced DCD lung transplantation with the first successful clinical case.A potential additional lung allograft source, DCD lung transplantation has been established with very acceptable outcomes observed by several centers. We provide the relevant background for the rationale of donor allograft expansion to include DCD lungs from controlled (Maastricht category III donors).This review considers the available evidence for DCD lung transplantation and compares reported primary graft dysfunction rates and current survival data available.

Rat lung allograft rejection is mediated by collagen type V (col(V)) specific T-helper-cell 17 (Th17) cells. Adoptive transfer of these cells is sufficient to induce rejection pathology in isografts, whereas tolerance to col(V) suppresses allograft rejection. Therefore, we tested whether regulatory T cells from tolerant rats could suppress the Th17-mediated rejection in the syngeneic model of lung transplantation.Rats were subjected to syngeneic left lung transplantation, and acute rejection was induced by adoptive transfer of lymph node cells from col(V)-immunized rats. Tolerance was induced by intravenous injection of col(V), and spleen lymphocytes were used for adoptive transfer. CD4+ T cells were depleted using magnetic beads. Lung isografts were analyzed using micro-positron emission tomography imaging and histochemistry. The transvivo delayed type hypersensitivity assay was used to analyze the Th17 response.Adoptive cotransfer of col(V)-specific effector cells with cells from col(V)-tolerized rats suppressed severe vasculitis and bronchiolitis with parenchymal inflammation, and the expression of interleukin (IL)-17 transcripts in mediastinal lymph nodes induced by effector cells alone. Analysis by transvivo delayed type hypersensitivity showed that the reactivity to col(V) was dependent on the presence of tumor necrosis factor-alpha and IL-17 but not interferon-gamma. Depletion of CD4+ T cells from the suppressor cell population abrogated the col(V)-specific protection.Th17-mediated acute rejection after lung transplantation is ameliorated by CD4+ col(V)-specific regulatory T cells. The mechanism for this Th17 suppression is consistent with tolerance induction to col(V). The goal of transplantation treatment, therefore, should target Th17 development and not suppression of T-cell activation by suppressing IL-2.

Lung volume reduction surgery (LVRS) is a palliative surgical procedure for patients with severe emphysema. Resection of nonfunctional emphysematous lung tissue has been reported to relieve breathlessness and to improve quality of life for many patients by improving lung elastic recoil, respiratory muscle function, and ventilation-perfusion matching. However, the risks and benefits of LVRS remain controversial, as mainly short-term data are available for carefully selected groups of LVRS patients and no prospective, randomized trials for LVRS with pulmonary rehabilitation versus optimal medical therapy plus pulmonary rehabilitation have been reported. Bilateral staple resection for LVRS appears to be superior to use of a laser or unilateral approach in the short term, but relatively little data exist on long-term outcomes. Additional clinical investigation is required to determine whether LVRS should be a widely accepted therapy for severe emphysema.

Background. The role of bone marrow-derived “passenger” leukocytes in the outcome of solid organ transplantation remains controversial. This study tested the relationship between high levels of donorderived leukocytes within the transplanted organ and clinical outcome after lung transplantation. Methods. Sequential bronchoalveolar lavage samples were obtained from human lung allograft recipients. Leukocytes of donor origin in the bronchoalveolar lavage fluid were detected using two-color immunofluorescence, and the results were correlated with multiple clinical parameters. Results. Mean donor leukocyte levels for the first 200 days after transplantation were higher in patients with a good transplantation outcome compared with those patients who lost their grafts due to acute rejection (AR) or developed bronchiolitis obliterans syndrome. The presence of low numbers of donor-derived leukocytes for the first 200 days after transplantation was found to be a significant risk factor for graft loss due to either acute or chronic rejection (P50.032). Nearly all patients (85%) experienced AR episodes. However, the time to onset of severe AR episodes was significantly longer (P50.049), and the incidence of these episodes reduced, in patients who maintained high numbers of donor-derived leukocytes for the first 200 days after transplantation. Conclusions. The presence of high numbers of donor-derived leukocytes, particularly macrophages, in the transplanted lung in the first 200 days after transplantation was associated with stable graft function. Donor-derived leukocytes were reduced or absent in patients with a poor transplantation outcome. These findings rule out a negative influence of persisting donor leukocytes and are consistent with the emerging two-way models of transplant tolerance.

Macromolecules are present in lung preservation solutions to limit liquid filtration out of the pulmonary circulation and minimize pulmonary edema. We tested the effectiveness of these molecules by measuring interstitial edema in rat lungs perfused with macromolecular solutions (University of Wisconsin [UW] solution and Euro-Collins solution supplemented with modified pentastarch [pentafraction, PEN]) or with solutions that lacked macromolecules (UW solution with PEN and Euro-Collins solution.) The lungs were inflated with air and perfused with one of the test solutions, then rapidly frozen and prepared for histological analysis. From tissue sections, we measured cross-sectional areas of pulmonary arteries and veins, and also measured cross-sectional areas of the interstitial spaces surrounding arteries and veins. We then calculated the interstitium-to-vessel cross-sectional area ratio. In lungs perfused with macromolecular solutions these ratios were 0.09+/-0.15 and 0.53+/-0.56 (mean +/- SD) for UW solution and Euro-Collins solutions solution with PEN, respectively (P

The current organ shortage has made utilization of organs from less-than-ideal donors more common. Although several transplant centers use kidneys from non-heart-beating donors (NHBDs), there has been reluctance to extend the use of these donors to extrarenal organs. Of the 130 donors referred to our organ procurement organization between January 1993 and May 1994, 16 (12.3%) were NHBDs. Organ retrieval from 10 of these resulted in extrarenal donation, 5 resulted in renal donation only, and 1 resulted in no retrieval as a result of prolonged warm ischemia (> 2 hr). A total of 39 organs were transplanted from these NHBDs. A rapid en bloc retrieval technique was used for extrarenal NHBDs. The mean warm ischemic time was 15.4 min; preservation times were similar for both NHBDs and heart-beating donors. After liver transplantation (n = 5), one episode of primary nonfunction that was technical in origin required retransplantation. Following simultaneous pancreas-kidney transplantation (n = 6), all patients were insulin independent and free of graft pancreatitis; one patient required hemodialysis (16.7%). After isolated renal transplantation (n = 21), 3 patients (14.3%) required hemodialysis. Three of 4 liver recipients are alive after a mean follow-up period of 12.7 months; all simultaneous pancreas-kidney and renal transplant recipients are alive after a mean follow-up period of 8.4 and 8.3 months, respectively. Three liver allografts, 5 pancreas and kidney allografts, and 19 renal allografts are functioning. The lung allograft was lost to rejection 81 days after transplantation; however, the recipient is alive 3 months after retransplantation. Our results demonstrate that in controlled situations, extrarenal organs can be utilized from NHBDs and can be expected to function similarly to organs retrieved from heart-beating donors. We increased the number of transplanted organs by 8.6% using NHBDs for both renal and extrarenal donation. Continued application of these techniques will likely further increase the number of organs retrieved for transplantation.

Two-dimensional echocardiography has a high specificity for the detection of intracardiac thrombi, but technically difficult studies are often encountered. Ultrafast cardiac computed tomography may be useful in such cases. Using transthoracic two-dimensional echocardiography and ultrafast cardiac computed tomography, we studied 36 patients with cerebral ischemia; one patient had the studies performed on two occasions, making a total of 37 sets of studies. Technical difficulties occurred in 12 echocardiographic (32%) and two ultrafast cardiac computed tomographic (5%) studies. The two techniques agreed in 29 sets of studies (78%). Among the eight discrepant sets of studies, two-dimensional echocardiography was positive for a left ventricular thrombus while ultrafast cardiac computed tomography was negative in three and equivocal in one and echocardiography was equivocal while ultrafast cardiac computed tomography was negative in two and positive in one. In the latter case, a left ventricular thrombus was confirmed at autopsy. In the other discrepant set of studies echocardiography was negative while ultrafast cardiac computed tomography revealed a left atrial and appendage thrombus. Because of its ease of performance and safety, two-dimensional echocardiography is the appropriate initial screening test for left ventricular thrombus. Ultrafast cardiac computed tomography can provide additional information in patients with technically difficult or equivocal two-dimensional echocardiographic studies or patients with cardiac disorders predisposing to atrial thrombi formation.