Hypotension Associated with MTS is Aggravated by Early Activation of TEA During Open Esophagectomy.

OBJECTIVE: A mesenteric traction syndrome (MTS) is elicited by prostacyclin (PGI2)-induced vasodilation and identified by facial flushing, tachycardia, and hypotension during abdominal surgery. We evaluated whether thoracic epidural anesthesia (TEA) influences the incidence of MTS. DESIGN: Randomized, blinded controlled trial. SETTING: Single-center university hospital. PARTICIPANTS: Fifty patients undergoing open esophagectomy. INTERVENTIONS: Patients were randomized to either early (EA, after induction of general anesthesia) or late activation of TEA (LA, after re-established gastric continuity). Plasma 6-keto-PGF1α, a stable metabolite of PGI2 and interleukine-6 (IL6) were measured in plasma during surgery along with hemodynamic variables and MTS graded according to facial flushing together with plasma C-reactive protein on the third post-operative day. RESULTS: Forty-five patients met the inclusion criteria. Development of MTS tended to be more prevalent with EA (n=13/25 [52%]) than with LA TEA (n=5/20 [25%], p=0.08). For patients who developed MTS, there was a transient increase in plasma 6-keto-PGF1α by 15 min of surgery and plasma IL6 (p<0.001) as C-reactive protein (P<0.009) increased. EA TEA influenced the amount of phenylephrine needed to maintain mean arterial pressure >60 mmHg in patients who developed MTS (0.16 [0.016-0.019] mg/min vs MTS and LA TEA 0.000 [0.000-0.005] mg/min, p<0.001). CONCLUSION: The incidence of MTS is not prevented by TEA in patients undergoing open esophagectomy. On the contrary, the risk of hypotension is increased in patients exposed to TEA during surgery, and the results suggest that it is advantageous to delay activation of TEA. Also, MTS seems to be associated with a systemic inflammatory response, maybe explaining the aggravated post-operative outcome.

Laser speckle contrast imaging for quantitative assessment of facial flushing during mesenteric traction syndrome in upper gastrointestinal surgery.

The mesenteric traction syndrome (MTS) is associated with prostacyclin (PGI2) facilitated systemic vasodilatation during surgery and is identified by facial flushing. We hypothesized that severe facial flushing would be related to the highest concentrations of plasma PGI2 and accordingly to the highest levels of skin blood flow measured by laser speckle contrast imaging (LSCI). Patients scheduled for major upper abdominal surgery were consecutively included. Within the first hour of the procedure, facial flushing was scored according to a standardized scale, and skin blood flow (LSPU) was continuously measured on the forehead and the cheeks by LSCI. Arterial blood samples for 6-keto-PGF1α (stable metabolite of PGI2) and hemodynamic variables were obtained at defined time points. Overall, 66 patients were included. After 15 min of surgery, patients with severe flushing demonstrated the highest plasma 6-keto-PGF1α concentration and the most significant decrease in systemic vascular resistance. Accordingly, the skin blood flow on the forehead (238 [201-372] to 562 LSPU [433-729]) and the cheeks (341 [239-355] to 624 LSPU [468-917]) increased and were significantly higher than for patients with moderate or no flushing (both, P = 0.04). A cut-off value for skin blood flow could be defined for both the cheeks and the forehead for patients with severe flushing vs. no flushing (425/456 LSPU, sensitivity 75/76% and specificity 80/85%). MTS is linked to an increase in facial skin blood flow during upper gastrointestinal surgery. By applying LSCI, it is possible to quantitatively register facial blood flow, and thereby provide an objective tool for intraoperative verification of MTS.