The Association Between Intraoperative Hypotension and Perioperative Stroke

Study Overview
=================
Brief Summary
-----------------
The aim of this study is to investigate the association between the severity and duration of intraoperative hypotension and the incidence of perioperative stroke after non-cardiac and non-neurologic surgeries.The secondary aim of this study is to confirm the potential risk factors of the perioperative stroke.

Detailed Description
-----------------
Optimized intraoperative management may play an important role in perioperative stroke prevention. Maintaining blood pressure near preoperative baseline values may help decrease the incidence of stroke, however the related evidence is limited.Therefore, this study is to investigate the association between intraoperative hemodynamic variable and the risk of perioperative stroke after non-cardiac and non-neurologic surgeries. The secondary aim of this study is to establish the potential risk factors of the perioperative stroke.

Official Title
-----------------
The Association Between Intraoperative Hypotension and Perioperative Stroke in General Surgery Patients: a Retrospective, Hospital-based Study in China

Conditions
-----------------
Perioperative Complication, Intraoperative Hypotension

Intervention / Treatment
-----------------
* Behavioral: Patiens with intraoperative hypotension


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients underwent surgeries in First hospital affiliated to Shandong First Medical University from January 2013 to October 2019 Age>18 or older Exclusion Criteria: Patients received local infiltration anesthesia Patients underwent total intravenous anesthsia without tracheal intubation or Laryngeal Mask Airway insertion Major vascular operation Neurologic surgery Cariac surgery Intraoperative blood pressure measurements or postoperative neuroimagings measurements are not available History of severe neurological or psychiatric disease

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Intraoperative hypotension<br> | Behavioral: Patiens with intraoperative hypotension<br>* In this study, we will use four previously defined thresholds for intraoperative hypotension: two absolute thresholds (MAP less than 50 mmHg and MAP less than 60 mmHg) and two relative thresholds to the baseline MAP (a decrease of 30% or more and a decrease of 40% or more). A definition of baseline value most frequently reported was the arterial blood pressure before the induction of anesthesia. Therefore, the baseline MAP used in calculating the relative thresholds is defined as the mean MAP of all available blood pressure measurements before induction of anesthesia in the operating room.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of perioperative stroke | Perioperative stroke diagnosed with CT or MRI examination, symptoms and signs | Within 24 hours after surgery | 
| Incidence of perioperative stroke | Perioperative stroke diagnosed with CT or MRI examination, symptoms and signs | Within 3 days after surgery | 
| Incidence of perioperative stroke | Perioperative stroke diagnosed with CT or MRI examination, symptoms and signs | Within 7 days after surgery | 
| Incidence of perioperative stroke | Perioperative stroke diagnosed with CT or MRI examination, symptoms and signs | Within 30 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of death | Death from any cause | Within 24 hours after surgery | 
| Rate of death | Death from any cause | Within 3 days after surgery | 
| Rate of death | Death from any cause | Within 7 days after surgery | 
| Rate of death | Death from any cause | Within 30 days after surgery | 
| Expense of Healthe care and social service | The expense of Healthe care and social service that the patients spent in hospital | Through study completion, an average of 14 days |