Open AccessMicrodialysis and CO2 sensors detect pancreatic ischemia in a porcine model
Author(s) -
Kristina Rydenfelt,
Runar Strand-Amundsen,
Rune Horneland,
Stina Hødnebø,
Gisle Kjøsen,
Søren Erik Pischke,
Tor Inge Tønnessen,
Håkon Haugaa
Publication year - 2022
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0262848
Subject(s) - microdialysis , ischemia , medicine , parenchyma , pco2 , occlusion , area under the curve , transplantation , thrombosis , urology , cardiology , anesthesia , pathology , central nervous system
Background Pancreatic transplantation is associated with a high rate of early postoperative graft thrombosis. If a thrombosis is detected in time, a potentially graft-saving intervention can be initiated. Current postoperative monitoring lacks tools for early detection of ischemia. The aim of this study was to investigate if microdialysis and tissue pCO 2 sensors detect pancreatic ischemia and whether intraparenchymal and organ surface measurements are comparable. Methods In 8 anaesthetized pigs, pairs of lactate monitoring microdialysis catheters and tissue pCO 2 sensors were simultaneously inserted into the parenchyma and attached to the surface of the pancreas. Ischemia was induced by sequential arterial and venous occlusions of 45-minute duration, with two-hour reperfusion after each occlusion. Microdialysate was analyzed every 15 minutes. Tissue pCO 2 was measured continuously. We investigated how surface and parenchymal measurements correlated and the capability of lactate and pCO 2 to discriminate ischemic from non-ischemic periods. Results Ischemia was successfully induced by arterial occlusion in 8 animals and by venous occlusion in 5. During all ischemic episodes, lactate increased with a fold change of 3.2–9.5 (range) in the parenchyma and 1.7–7.6 on the surface. Tissue pCO 2 increased with a fold change of 1.6–3.5 in the parenchyma and 1.3–3.0 on the surface. Systemic lactate and pCO 2 remained unchanged. The area under curve (AUC) for lactate was 0.97 (95% confidence interval (CI) 0.93–1.00) for parenchymal and 0.90 (0.83–0.97) for surface ( p <0.001 for both). For pCO 2 the AUC was 0.93 (0.89–0.96) for parenchymal and 0.85 (0.81–0.90) for surface ( p <0.001 for both). The median correlation coefficients between parenchyma and surface were 0.90 (interquartile range (IQR) 0.77–0.95) for lactate and 0.93 (0.89–0.97) for pCO 2 . Conclusions Local organ monitoring with microdialysis and tissue pCO 2 sensors detect pancreatic ischemia with adequate correlation between surface and parenchymal measurements. Both techniques and locations seem feasible for further development of clinical pancreas monitoring.