Influencing factors of dexmedetomidine on postoperative myocardial protection in patients with Video-Assisted Thoracoscopic Surgery lobectomy: A retrospective cohort study

Objective: To investigate factors affecting the cardioprotective proprieties of dexmedetomidine in patients after pulmonary lobectomy.

Methods: The data of 504 patients who received dexmedetomidine combined with general anesthesia and video-assisted thoracoscopic surgery (VATS) lobectomy in Shanghai Lung Hospital from April 2018 to April 2019 were analyzed retrospectively. Patients were divided into normal troponin group (LTG) and high troponin group (HTG) according to whether the postoperative troponin level was greater than 13. Ratio of systolic blood pressure greater than 180, heart rate greater than 110, the dose of dopamine and other drugs, the ratio of neutrophils to lymphocytes, postoperative visual analog scale (VAS) pain score and hospital stay were compared between the two groups.

Results: Preoperative systolic blood pressure, intraoperative maximum systolic blood pressure, intraoperative maximum heart rate, intraoperative minimum heart rate and N-terminal pro hormone brain natriuretic peptide (NT-proBNP) correlated with troponin values. The proportion of patients with systolic blood pressure greater than 180 in the HTG was higher than that in the LTG (p=0.0068), and the proportion of patients with heart rate greater than 110 was significantly higher in the HTG compared to the LTG (p=0.044). The ratio of neutrophils/lymphocytes in the LTG was lower than that in the HTG (P<0.001). At 24 and 48 hours after operation, the VAS score in the LTG was lower than that in the HTG. Patients with high troponin had longer hospital stay.

Conclusions: Intraoperative systolic blood pressure, maximum heart rate, and postoperative neutrophil/lymphocyte ratio are important factors that affect the myocardial protection properties of dexmedetomidine and may affect the postoperative analgesia effect and the length of hospital stay.