The use of the Papworth cocktail is detrimental to steatotic livers after ischemia-reperfusion injury

Donor thyroid hormone therapy and heart transplantation outcomes: ISHLT transplant registry analysis

BACKGROUND

Donor thyroid hormone (TH) supplementation therapy is widely used. Recent reports suggested an increased risk of graft dysfunction in heart transplant (HTx) recipients not receiving TH supplementation. Our aim was to determine the effect of a donor TH supplementation in a large contemporary HTx cohort.

METHODS

We analyzed data reported to the International Society for Heart and Lung Transplantation Registry on adult HTx recipients transplanted from 2006 to 2016. Early graft loss (EGL) was defined as death or retransplant because of graft failure within 48 hours of transplant. Logistic regression and propensity score analyses were performed.

RESULTS

There were 23,002 adult HTx recipients transplanted during the study period for whom data on the use of donor TH supplementation were provided to the Registry. There were 15,821 recipients whose donors had received TH supplementation, and 7,181 who had not. Multivariable analysis showed donor TH therapy to be associated with an increased risk for EGL (odds ratio, 1.51; 95% CI, 1.13-2.06; p < 0.001). Long-term survival was similar, irrespective of donor TH supplementation. Recipients whose donors had received TH supplementation exhibited a lower 8-year incidence of vasculopathy (hazard ratio, 0.90; 95% CI, 0.85-0.97; p = 0.003). These results remained consistent in a propensity-matched analysis.

CONCLUSIONS

Donor TH therapy is independently associated with an increased risk of EGL. Whether this is a result of the donor allograft intrinsic characteristics related to the reasons why TH was used or whether this is a result of a TH withdrawal effect, which could be mitigated by administration of TH to the recipient, should be further studied.

A Pilot Randomized Controlled Trial Comparing Levothyroxine to Placebo in Neurologically Deceased Donors

BACKGROUND

Although commonly prescribed, the efficacy of levothyroxine to improve heart function in neurologically deceased donors is unclear. We evaluated the feasibility of a randomized controlled trial to compare levothyroxine to placebo on the variation of left ventricular ejection fraction, in hemodynamically unstable donors.

METHODS

We conducted a pilot, double-blinded, randomized controlled trial. Deceased donors with reduced left ventricular ejection fraction or needing vasopressors were included. We randomized participants to a 20 μg bolus followed by a 20 μg/h infusion of levothyroxine or an identically appearing placebo. We report the proportion of recruited participants, the time to the administration of the study drug, and protocol violations.

RESULTS

Twenty-four participants (N = 24/104; 23.1%) were eligible. Five of them (N = 5/24; 20.8%) were excluded by the attending physician. Four others were not included, due to family refusal for research (n = 2/24;8.3%) and unavailability of research staff (n = 2/24; 8.3%). Fifteen participants were randomized (N = 15/104; 14.4%). Mean time between the echocardiography and the initiation of the drug was 1.73 hours, and14 (93.3%) of 15 of the participants received the drug within 2 hours after the echocardiography. We report no study violation. The study was stopped prematurely because of low recruitment.

CONCLUSION

This pilot trial suggests that the success of a definitive randomized control trial to assess the efficacy of levothyroxine in deceased donors could benefit from a multicenter recruitment and education on the evidence surrounding the pharmacological management of organ donors. The need for consent to research interventions in deceased donors should also be clarified.

Understanding the effect of corticosteroid pretreatment in brain-dead organ donors: new mechanistic insights for improvement of organ quality in liver transplantation

Transplant surgeons are currently faced with the challenge to accept marginal liver transplants due to steatosis or old age. Improving organ quality by implementing a selective organ protective donor management could be the first step towards a graft of enhanced quality. However, the molecular mechanisms of such treatments are still poorly understood. Glucocorticoid medication in donor medicine has been carried out and discussed for a long time. In a recent study published in Clinical Science, Jiménez-Castro et al. [Clin. Sci. (2017) 131, 733-746] demonstrate how liver histology and transplant liver function can be improved by administration of glucocorticoids to brain-dead donor rats with steatotic livers. This work illustrates the need for further trials in order to selectively improve the quality of steatotic livers with a potential for liver transplantation.

Management of the heartbeating brain-dead organ donor

The main factor limiting organ donation is the availability of suitable donors and organs. Currently, most transplants follow multiple organ retrieval from heartbeating brain-dead organ donors. However, brain death is often associated with marked physiological instability, which, if not managed, can lead to deterioration in organ function before retrieval. In some cases, this prevents successful donation. There is increasing evidence that moderation of these pathophysiological changes by active management in Intensive Care maintains organ function, thereby increasing the number and functional quality of organs available for transplantation. This strategy of active donor management requires an alteration of philosophy and therapy on the part of the intensive care unit clinicians and has significant resource implications if it is to be delivered reliably and safely. Despite increasing consensus over donor management protocols, many of their components have not yet been subjected to controlled evaluation. Hence the optimal combinations of treatment goals, monitoring, and specific therapies have not yet been fully defined. More research into the component techniques is needed.

The effect of hepatic ischemia reperfusion injury in a murine model of nonalcoholic steatohepatitis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) refers to an increasingly diagnosed condition involving triglyceride accumulation into hepatocytes resulting in a broad spectrum of liver injury. The progression of NAFLD, a relatively benign condition, to nonalcoholic steatohepatitis (NASH) involves the hepatic infiltration of inflammatory cells and subsequent hepatocellular injury. Ischemia/reperfusion (I/R) injury of the liver is a major complication of liver resection, hepatic trauma, and liver transplantation. To date, there have been no studies that have evaluated the effects of hepatic I/R on models of NASH.

OBJECTIVE

Evaluate the effects of hepatic I/R on a mouse model of NASH.

METHODS

A mouse model of progressive NASH was developed and evaluated using C57BL/6 mice fed a methionine choline deficient diet for 3, 6, 9, and 12 wk. Mice subsequently underwent 90 min of partial hepatic ischemia with reperfusion of 1, 4, and 8 h. Mice were sacrificed after the indicated periods, and blood and liver samples were taken for analysis.

RESULTS

Mice fed the MCD diet showed a rapid induction of hepatic steatosis, inflammation, and fibrosis by 3 wk that persisted over the 12-wk period of diet, as demonstrated by histologic examination, alanine aminotransferase (ALT), and liver content of myeloperoxidase (MPO). The response to I/R in livers with progressive NASH fed MCD diet for 3, 6, 9, and 12 wk showed marked neutrophil recruitment and hepatocyte necrosis.

CONCLUSION

These data suggest the inflammatory response from I/R is augmented in livers with NASH histopathology compared with normal liver.

Murine Kupffer cells are protective in total hepatic ischemia/reperfusion injury with bowel congestion through IL-10

Kupffer cells (KCs) are thought to mediate hepatocyte injury via their production of proinflammatory cytokines and reactive oxygen species in response to stress. In this study, we depleted KCs from the liver to examine their role in total warm hepatic ischemia/reperfusion (I/R) injury with bowel congestion. We injected 8-wk-old C57BL/10J mice with liposome-encapsulated clodronate 48 h before 35 min of hepatic ischemia with bowel congestion, followed by 6 or 24 h of reperfusion. KC-depleted animals had a higher mortality rate than diluent-treated animals and a 10-fold elevation in transaminase levels that correlated with increases in centrilobular necrosis. There was extensive LPS binding to the endothelial cells, which correlated with an upregulation of endothelial adhesion molecules in the KC-depleted animals versus diluent-treated animals. There was an increase in the levels of proinflammatory cytokines in KC-depleted animals, and a concomitant decrease in IL-10 levels. When KC-depleted mice were treated with recombinant IL-10, their liver damage profile in response to I/R was similar to diluent-treated animals, and endothelial cell adhesion molecules and proinflammatory cytokine levels decreased. KCs are protective in the liver subjected to total I/R with associated bowel congestion and are not deleterious as previously thought. This protection appears to be due to KC secretion of the potent anti-inflammatory cytokine IL-10.