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Updated: Apr 20, 2026
Real-Time Assessment of Spinal Cord Microperfusion in a Porcine Model of Ischemia/Reperfusion
Published on: December 10, 2020
Real-time measurement of rectal mucosal microcirculation during cardiopulmonary bypass
Arndt-H Kiessling1, Christian Reyher2, Michael Philipp1
1Department of Thoracic and Cardiovascular Surgery, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Frankfurt am Main, Germany.
Objectives:
Mesenteric ischemia is still a fatal event after cardiac procedures. No adequate intraoperative methods are available to monitor the gastrointestinal mucosal microcirculation in real-time conditions. The aim of the study was to assess a newly designed microprobe using laser Doppler flowmetry and remission spectroscopy.
Design:
One-group, prospective, nonrandomized, open, pilot diagnostic study.
Setting:
Monocenter university hospital.
Participants:
50 patients (n = 38 males, 67±6 years) scheduled for cardiopulmonary bypass (CPB) were prospectively included.
Intervention:
During anesthetic induction, the transrectal microprobe (30×15 mm) was positioned between the inferior and middle rectal valve (5-8 cm). Time periods were summarized at T1 = pre-CPB, T2 = CPB, T3 = post-CPB.
Measurements And Main Results:
In 39 of 50 patients, data recruitment with the microprobe was successful. Measurement failures were due to fecal contaminations and probe dislocations. Rectal blood flow and velocity significantly decreased after bypass initiation (T2). Lowest flow rates were recorded after cross-clamp removal and did not recover at the end of bypass (T3). No side effects of the probe were noted.
Conclusions:
The new microprobe allows reproducible, safe, intraoperative, real-time evaluation of the rectal mucosal microcirculation. It could be a useful diagnostic tool to prevent mesenteric ischemia by optimizing extracorporeal circulation in future studies. However, first correlation of rectal blood flow and postoperative events (eg, ischemia, lactate) in a large cohort are necessary.
