Cool Perfusion –Better Liver Transplant Outcomes

R van Rijn et al. NEJM 2021; 384: 1391-1401. Hypothermic Machine Perfusion in Liver Transplantation — A Randomized Trial

Background: Nonanastomotic biliary strictures are a major complication after liver transplantation, and ischemia–reperfusion injury is a key mechanism in their development. Although static cold preservation provides some protection against injury, preclinical studies have shown that a short period of hypothermic oxygenated machine perfusion restores mitochondrial function and reduces damage.

Methods: In this multicenter, controlled trial, we randomly assigned patients who were undergoing transplantation of a liver obtained from a donor after circulatory death to receive that liver either after hypothermic oxygenated machine perfusion (machine-perfusion group) or after conventional static cold storage alone (control group). A total of 160 patients were enrolled, of whom 78 received a machine-perfused liver and 78 received a liver after static cold storage only (4 patients did not receive a liver in this trial).

Key points:

  • Nonanastomotic biliary strictures occurred in 6% of the patients in the machine-perfusion group and in 18% of those in the control group, risk ratio, 0.36
  •  Postreperfusion syndrome occurred in 12% of the recipients of a machine-perfused liver and in 27% of those in the control group; risk ratio, 0.43
  • Early allograft dysfunction occurred in 26% of the machine-perfused livers, as compared with 40% of control livers; risk ratio, 0.61

My take: Hypothermic oxygenated machine perfusion led to lower risk of nonanastomotic biliary strictures

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NASPGHAN Postgraduate Course 2014 -Endoscopy Module

This blog entry has abbreviated/summarized the presentations. Though not intentional, some important material is likely to have been omitted; in addition, transcription errors are possible as well.  Link to full syllabus:

PG Course Syllabus 2014

The Dreaded Wake-Up Call (Part A) –Maercedes Martinez (NY Presbyterian Hospital) (pg 55 syllabus)

Variceal Bleeding – “When RED is not attractive

Discussed presentation of varices (gastric/esophageal), etiologies, association with portal hypertension. Reviewed variceal grading.

Medical management:

  • PICU admit
  • Avoid over-transfuse (goal ~ 8 g/dL)
  • Correct coagulopathy
  • Role of platelets is controversial/if trouble with endoscopy, may be helpful
  • Suggested dosing for octreotide/somatostatin: 2 mcg/kg bolus then 1-2 mcg/kg/hr (typically max 100 mcg/hr), antibiotics
  • Most patients do not require emergency overnight endoscopy.
  • Sclerotherapy and banding reviewed -including complications.
  • Transjugular intrahepatic portosystemic shunts (TIPS) and Surgical options briefly discussed

The Dreaded Wake-Up Call (Part B) –Lee Bass (Children’s Hospital of Chicago) (pg 67 in syllabus)

Nonvariceal GI Bleeding Management

  • Start with ABCs -airway, breathing, cardiovascular –fluid resuscitation/blood products
  • Restrictive transfusion strategy (Hgb <7 as threshold) (Villanueva et al NEJM 2013) helpful for survival in adults
  • Treatment with PPI improves rates of high risk stigmata on endoscopy
  • Prokinetics can improve identication of bleeding lesions
  • Preparation for endoscopy is most important (slide on page 70 of syllabus)
  • Also on page 70, pictures of typical findings with GI bleeding: nonbleeding vessel, adherent clot, spurting blood, oozing blood, and flat pigmented spot and clean base
  • Endoscopic management -combination of two techniques appears to be more effective than single method. injection, thermal probe, hemoclips, hemospray (not available in U.S.

Endoscopic Interventions for Biliary Tract Disease — Victor Fox (pg 75 in Syllabus)

Choledocholithiasis is most common need for interventional biliary endoscopy and increasing related to increase risk with increase in obesity.(Buxbaum J. Gastrointest Clin N Am 2013;23:251‐75)

Requires advanced training to achieve high level of skill and experience

  • >200 cases needed to achieve selective cannulation required for interventions
  •  Acquisition and maintenance of skills by pediatricians is controversial

Other points:

  • No equipment is favorably designed for young or small children
  • Success and complication rates are similar as in adults (Varadarajulu S, et al. Gastrointest Endosc 2004;60:367)
  • Discussed biliary strictures (etiologies, management/stents), choledochocele, papillotomy, bile leak (Soukup ES et al. J Pediatr Surg 2014;49:345‐8)
  • “Most strictures and leaks can be successfully managed endoscopically without need for surgical intervention”

Take-home message: Endoscopic biliary interventions are increasingly employed in children with similar safety and technical success as adult patients

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Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.