Early detection of complications in pancreas transplants by microdialysis catheters, an observational feasibility study

Abstract

Background Despite advances in immunosuppression and surgical technique, pancreas transplantation is encumbered with a high rate of complication and graft losses. Particularly, venous graft thrombi occur relatively frequently and are rarely detected before the transplant is irreversibly damaged. Methods To detect complications early, when the grafts are potentially salvageable, we placed microdialysis catheters anteriorly and posteriorly to the graft in a cohort of 34 consecutive patients. Glucose, lactate, pyruvate, and glycerol were measured at the bedside every 1–2 hours. Results Nine patients with graft venous thrombosis had significant lactate and lactate–to-pyruvate-ratio increases without concomitant rise in blood glucose or clinical symptoms. The median lactate in these patients was significantly higher in both catheters compared to non-events (n = 15). Out of the nine thrombi, four grafts underwent successful angiographic extraction, one did not require intervention and four grafts were irreversibly damaged and explanted. Four patients with enteric anastomosis leakages had significantly higher glycerol measurements compared to non-events. As with the venous thrombi, lactate and lactate-to-pyruvate ratio were also increased in six patients with graft surrounding hematomas. Conclusions Bedside monitoring with microdialysis catheters is a promising surveillance modality of pancreatic grafts, but differentiating between the various pathologies proves challenging.

Cerebral perfusion and metabolism with mean arterial pressure 90 vs. 60 mmHg in a porcine post cardiac arrest model with and without targeted temperature management

“…12À16 Microdialysis offers the ability to measure tissue lactate, pyruvate, glucose, glutamate and glycerol, and disturbances in these metabolic factors correlates with functional outcome in patients. 39À44 Under anaerobic conditions a pattern of increased lactate, decreased pyruvate and glucose and increased lactate/pyruvate-ratio is formed, 15,45 and this was also confirmed in the present study. After ROSC both lactate and pyruvate increased and lactate/pyruvate-ratio decreased, which previously has been described to be caused by inflammatory conditions and tissue oedema.…”

Microdialysis and CO2 sensors detect pancreatic ischemia in a porcine model

“…The successful biosensor based local detection of pancreatic ischemia, together with the absence of systemic markers of ischemia, supports the previous findings, and emphasizes the need for local tissue monitoring [17,19].…”

“…Parenchymal monitoring is probably more reliable due to little or no influence from surrounding conditions. On one hand, surface sensors can be affected by surrounding conditions such as a hematoma, accumulated lactate in abdominal fluid or a local infection [ 19 ]. On the other hand, surface monitoring is less invasive and presumptively safer.…”

“…Microdialysis catheters positioned in the parenchyma have confirmed pancreatic ischemia in a porcine model in vivo [ 17 ], in porcine and human pancreases ex vivo[ 18 ], and we have monitored pancreas grafts with microdialysis catheters on the organ surface [ 19 ]. There is no clinical experience with intraparenchymal pancreatic tissue monitoring.…”

Local Postoperative Graft Inflammation in Pancreas Transplant Patients With Early Graft Thrombosis

“…We have already used microdialysis catheters to investigate changes in local metabolites concerning early postoperative complications in pancreas-transplanted patients. 17 Microdialysis has also been used to investigate local tissue inflammation in several other organs. [18][19][20] In liver transplantation, patterns of local inflammatory mediators have distinguished grafts with early postoperative ischemia from those with rejections or no complications.…”