Chronic Angiotensin Converting Enzyme Inhibitors in Intermediate Risk Surgery

Study Overview
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Brief Summary
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Primary research hypothesis: Patients who continue their chronic ACEI therapy up to and including the morning of a non-cardiac, non-vascular surgery will experience more intraoperative hypotension than those who transiently hold their chronic ACEI preoperatively. Secondary research hypothesis #1: Patients who continue their chronic ACEI up to and including the morning of a non-cardiac, non-vascular surgery will experience better postoperative control of hypertension than those who transiently hold their chronic ACEI preoperatively. Secondary research hypothesis #2: Patients who continue their chronic ACEI up to and including the morning of a non-cardiac, non-vascular surgery will experience less acute renal failure than those who transiently hold their chronic ACEI preoperatively. Secondary research hypothesis #3: In the subgroup of patients with a preoperative systolic blood pressure less than 110 mmHg, those who continue their chronic ACEI therapy up to and including the morning of a non-cardiac, non-vascular surgery will experience more intraoperative hypotension than those who transiently hold their chronic ACEI preoperatively. Secondary research hypothesis #4: In the subgroup of patients above the age of 64, those who continue their chronic ACEI therapy up to and including the morning of a non-cardiac, non-vascular surgery will experience more intraoperative hypotension than those who transiently hold their chronic ACEI preoperatively.

Detailed Description
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The purpose of this study is to determine if transient discontinuation of angiotensin converting enzyme inhibitors (ACEIs) is necessary prior to non-cardiac, non-vascular surgery. ACEIs have been associated with intraoperative hypotension during vascular and cardiac surgeries. Patients presenting to the University of Nebraska Medical Center Pre-Anesthesia Screening (PAS) Clinic who are on chronic ACEI therapy will be eligible for enrollment. Subjects will be randomized to either omit or continue their ACEI preoperatively. The outcome of interest is intraoperative hypotension defined as a systolic blood pressure less than 80 mmHg. Blood pressure will be followed not only throughout surgery, but also during recovery and the remainder of hospitalization. Renal function will be assessed with creatinine measurements in the PAS clinic and on the first postoperative day. No follow-up is planned beyond discharge from the hospital.

Official Title
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Chronic Angiotensin Converting Enzyme Inhibitors in Intermediate Risk Surgery: A Randomized, Single-Blinded Study

Conditions
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Hypotension on Induction

Intervention / Treatment
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* Drug: ACEI continuation
* Drug: ACEI omission


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Referred to the University of Nebraska Medical Center Pre-Anesthesia Screening Clinic for preoperative evaluation. Above referral must be in anticipation of a non-cardiac, non-vascular surgery. Must have been on ACE-Inhibitor therapy for at least six weeks. Exclusion Criteria: Hypotension (systolic blood pressure < 90 or diastolic blood pressure <60) at the time of preoperative evaluation Uncontrolled Hypertension (systolic blood pressure > 150 or diastolic blood pressure > 95) at the time of preoperative evaluation Surgery during which vasopressor use is anticipated (carotid endarterectomy, major abdominal operations, orthopedic oncology) Surgery for pathology related to vasoactive substances (carcinoid, pheochromocytoma) Left Ventricular ejection fraction less than 40% Clinical evidence of decompensated heart failure at the time of preoperative evaluation End-stage renal disease Organ transplant surgeries

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 90 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ACEI continuation<br>Patients in this arm will be randomized to continue their chronic angiotensin converting enzyme inhibitor without interruption preoperatively | Drug: ACEI continuation<br>* These chronic medications will be taken without interruption preoperatively.<br>* Other names: Univasc;|
| Experimental: ACEI omission<br>Patients randomized to this arm will be told to omit their final preoperative chronic angiotensin converting enzyme inhibitor dose. | Drug: ACEI omission<br>* Although taken chronically by patients in this intervention, the final preoperative dose of these medications will be omitted, whether it was scheduled for the morning of surgery or the day prior.<br>* Other names: Univasc;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Interoperative Hypotension | Number of Participants with Interoperative Hypotension (systolic blood pressure under 80 mmHg) | During anesthesia, an expected average of 3 hours. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute Renal Failure | Creatinine increase of more than 0.3 mg/dl or more than 50% from preoperative level | Arrival in post-anesthesia care unit (PACU) to hospital discharge, an expected average of 4 days. | 
| Low Blood Pressure Subgroup | Only patients with systolic blood pressure less than 110 at preoperative evaluation will be included in this analysis. The outcome is the same as the primary outcome: Intraoperative Systolic Blood Pressure under 80 mmHg. | During anesthesia, an expected average of 3 hours. | 
| Older Age Subgroup | Only patients above the age of 64 will be included in this analysis. The outcome is the same as the primary outcome: Intraoperative Systolic Blood Pressure under 80 mmHg | During anesthesia, an expected average of 3 hours. | 
| Postoperative Hypertension | Any systolic blood pressure greater than 180 mmHg. | Arrival in PACU to hospital discharge, an expected average of 4 days. | 
| Postoperative Hypotension | Any systolic blood pressure less than 90 mmHg | Arrival in PACU to hospital discharge, an expected average of 4 days. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Perioperative Period