Intraoperative Hypotension and Related Risk Factors for Postoperative Mortality After Noncardiac Surgery in Elderly Patients: A Retrospective Analysis Report

Abstract

Background

Blood pressure fluctuation is very common during non-cardiac surgery in elderly. This retrospective study was to analyse whether intraoperative hypotension in elderly and other risk factors relate to the postoperative mortality.

Methods

A total of 118 cases (Observational group), who underwent noncardiac surgery in three medical centers between September 2014 and March 2017, and died in the hospital after the noncardiac surgery. With 1:2 ratio of propensity matching, 236 survival cases (Control group) were selected for comparison analyses with the death cases. Intraoperative blood pressure and perioperative parameters from both groups were collected from electronic anaesthesia charts. Data were analysed with univariate logistic regression analysis where variables with p values less than 0.05 were analysed with multivariate logistic regression analysis. The receiver operating characteristic (ROC) curve was constructed.

Results

There are five risk factors related to postoperative death in elderly patients: ASA grade, COPD, emergency surgery, general anesthesia, 60 < MAP ≤ 65mmHg (OR > 1), and one factor may reduce the risk of postoperative mortality, which is PACU therapy (OR < 1). Compared with the Control group, the Observational group had a higher proportion of cerebral hernia, kidney injury and trauma (p < 0.001). The intraoperative blood transfusion volume and intraoperative blood loss volume were higher in the Observational group than the Control group (p < 0.001). The proportion of using vasoactive drugs was higher in the Observational group (p < 0.001), and there was more urine output during the operation in the Observational group (p = 0.005).

Conclusion

The intraoperative MAP of geriatric patients lower than 65mmHg is highly related to the postoperative mortality. Elderly patients with emergency surgery, high ASA grade and a history of COPD have an increased risk of postoperative mortality. General anesthesia is a risk factor for postoperative death in elderly patients, and the PACU therapy is a protective factor to avoid postoperative death.

Trial Registration

This study has been retrospectively registered in the Chinese Clinical Trials Registry (ChiCTR2000038912, 10/10/2020).

Keywords:

• intraoperative hypotension
• geriatric patients
• COPD
• postoperative mortality
• non-cardiac surgery

Acknowledgments

The authors would like to thank Professor Daqing Ma, Division of Anaesthetics, Pain Medicine & Intensive Care, Imperial College London for spending his valuable time on reading the manuscript and providing valuable suggestions. We appreciate the support from the National Key R&D Program of China (No. 2018YFC0116703) and the Excellent Talents Foundation of Army Medical University (XZ-2019–505-028). Benhui Zhao and Xingtong Chen are co-first authors for this study.

Abbreviations

95% CI, 95% confidence interval; ASA, American Society of Anesthesiologists; AUC, Area under the curve; IOH, intraoperative hypotension; COPD, chronic obstructive pulmonary disease; PACU, postanesthesia care unit; ROC, Receiver operating characteristic; RR, Risk ratio; MAP, mean arterial pressure; SBP, systolic blood pressure; MODS, multiple organs dysfunction syndrome; OR, odds ratio; ACC, American College of Cardiology; AHA, American Heart Association. BMI, Body Mass Index; NYHA, New York Heart Association; CHD, Coronary Heart Disease; ICU, Intensive Care Unit; AKI, Acute Kidney Injury; ARDS, Acute Respiratory Distress Syndrome.

Data Sharing Statement

The datasets used and/or analysed during the current study are available from the corresponding author, Jianteng Gu, on reasonable request.

Ethics Approval and Consent to Participate

The study was approved and the written informed consent was waived by the Ethics Committee of the First Affiliated Hospital (Southwest Hospital) of Army Medical University, PLA [KY2020182], by the Medical Ethics Committee of Second Affiliated Hospital (Xinqiao Hospital) of Army Medical University, PLA [2020-119-01] and by the Ethics Committee of Army Specialty Medical Center (Daping Hospital) of Army Medical University, PLA [2020.No.147] respectively. This study has been retrospectively registered in the Chinese Clinical Trials Registry (ChiCTR2000038912, 10/10/2020). All methods performed in this study were in accordance with the relevant guidelines and regulations. All procedures performed in this study involving human participants were in accordance with the Ethical Standards of the Institutional Ethics Committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Disclosure

The authors report no conflicts of interest in this work.