Correlation Between Postprandial Hypotension and Post-induction Hypotension in the Elderly.

Study Overview
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Brief Summary
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Postprandial hypotension (PPH) and post-induction hypotension (PIH) are very common in the elderly population and are associated with a variety of poor outcomes.The purpose of this study is to investigate the correlation between PPH and perioperative adverse events such as PIH in the elderly.

Detailed Description
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With the deepening of the aging population in our country, the number of elderly patients undergoing surgery is also increasing. Elderly patients are at higher risk for hemodynamic instability due to organ dysfunction, decreased physiological reserve, and the coexistence of multiple chronic diseases.Postprandial hypotension (PPH) is common but often unrecognized among the elderly.PPH is defined as a fall in systolic blood pressure of >20 mm Hg, or a decrease to ≤90 mm Hg when preprandial systolic blood pressure is ≥100 mm Hg within 2 hours of a meal.The pathophysiology of PPH is not clear, the decreased cardiovascular autonomic function may play an important role. Post-induction hypotension (PIH) occurs after induction but before surgical incision and autonomic dysfunction is regarded as one of the major mechanisms.This study aims to prospectively explore the correlation between PPH and perioperative adverse events such as PIH in the elderly.

Official Title
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Correlation Between Postprandial Hypotension and Perioperative Adverse Events Such as Post-induction Hypotension in the Elderly: a Prospective Observational Study.

Conditions
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Postprandial Hypotension, Post-induction Hypotension

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elderly patients (≥ 65 years old）; Elective non-cardiac surgery; Patients with American Society of Anesthesiologists(ASA) grade I-III; Patients will undergo general anesthesia by endotracheal tube; Patients who are willing to participate in this research. Exclusion Criteria: Severe vascular disease; Secondary hypertension; Chronic kidney disease (CKD) stage 5; Unable to measure upper extremity blood pressure accurately; Dental or oral swallowing disorders or unable to eat independently; Patients or their families refuse to participate in this research.

Ages Eligible for Study
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Minimum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Postprandial hypotension group<br>Patients who have a fall in systolic blood pressure of >20 mm Hg, or a decrease to ≤90 mm Hg when preprandial systolic blood pressure is ≥100 mm Hg within 2 hours of the lunch | |
| No postprandial hypotension group<br>Patients who do not meet the postprandial hypotension criteria within 2 hours of the lunch | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-induction hypotension | which is defined as systolic blood pressure (SBP) <90 mm Hg or a decrease of more than 30% from baseline blood pressure, mean arterial pressure(MAP)<65 mm Hg or a decrease of more than 30% from baseline blood pressure within 20 minutes after induction or before incision. | Within 20 minutes after induction or before incision. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative complications | We will use the Clavien-Dindo system to grade postoperative complications. | Within 30 days after surgery |