Involvement of capillary endothelial dysfunction and decreased plasma calcium concentration in persistent severe hypotension during pancreaticoduodenectomy

Intraoperative persistent severe hypotension (PSH) is a common complication following pancreaticoduodenectomy (PD) and may affect the prognosis of patients. The aim of this trial was to explore the ultrastructural alterations of capillary endothelia cells and relevant factors that is associated with PSH and postoperative outcomes in patients undergoing PD.

Total 103 patients were divided into PSH or non-PSH group during PD. The basic clinical features, hemodynamic monitoring, electrolyte biochemical indexes, postoperative inflammatory biomarkers and adverse outcomes were analyzed. Particularly, the great omentum samples were collected and the morphological changes of capillary endothelial cells were revealed by electronic microscopy.

PSH occurred in forty-four patients (42.7%) during PD. The PSH patients experienced greater extensive surgery scope, more bleeding, longer surgery time, increased fluid infusion and blood glucose. Hemodynamic monitoring revealed that the PSH patients primarily showed reduced vascular resistance with enhanced cardiac index. The postoperative inflammation biomarkers and incidence of postoperative complications in PSH group were significantly higher than those in non-PSH group (P < 0.05). Notably, the arterial plasma Ca²⁺ decreased significantly in PSH patients as that in non-PSH group (P < 0.001). Electron microscopy revealed in PSH patients ultrastructural evidence of capillary endothelial injury, including cellular swelling and increased pinocytotic activity.

Endothelial cell permeability alteration and endothelial dysfunction might potentially reflect intensive surgical stress-inflammation-endocrine responses during PD. Endothelial edema formation and decreased plasma Ca²⁺ are probably associated with PSH and postoperative adverse outcomes of PD patients.Our study highlights the key point to keep the functionality and integrity of endothelia cells and timely supplement calcium to prevent PSH during pancreaticoduodenectomy and postoperative outcomes.