A Pilot Analysis of the Association Between Anesthesia Induction Dosing and AKI in the Elderly Population

Study Overview
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Brief Summary
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This study proposes to perform a pilot observational study looking at the doses of propofol used for the induction of general anesthesia and its association with the development of hypotension and AKI among elderly patients at YNHH.

Detailed Description
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The first stage of this study proposes to perform a pilot observational study looking at the doses of propofol used for the induction of general anesthesia. We will determine the percent (as a function of age, Elixhauser score, ASA status) of patients who receive more than the FDA approved induction dosage. We estimate 30% with the power defined as the width of the 95 percent confidence interval around that number that is given by 80% power and n=500. In the second stage, the investigators will look at the association between dose and the development of hypotension (in the time after induction and before surgical incision) and post-operative AKI among elderly patients at YNHH while controlling for age, Elixhauser score, and ASA status. The results of this study will also hopefully be used in a quality improvement project to prevent overdosing of the elderly patient population with induction anesthetic. Hypothesis 1: Elderly patients are being overdosed (per FDA guidelines) with anesthetic agents for induction of general anesthesia. Hypothesis 2: Overdose of anesthetic agents for induction of general anesthesia in the elderly population leads to an increased chance of developing AKI. Hypothesis 3: Overdose of anesthetic agents for induction of general anesthesia in the elderly population leads to an increased chance of developing hypotension post-induction, which may contribute to development of AKI or vice-versa. This research will be done via analysis of data and associated records contained in the Multicenter Perioperative Outcomes Group databases at Yale (the latter is a research database approved under HIC#1206010438). The possible risks are primarily the risk to privacy that is inherent in any retrospective chart review. The benefit may be to suggest areas for quality improvement in induction practices for elderly patients at YNHH and elsewhere.

Official Title
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A Pilot Analysis of the Association Between Anesthesia Induction Dosing and Acute Kidney Injury (AKI) in the Elderly Population

Conditions
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Acute Kidney Injury, Hypotension, Anesthesia; Adverse Effect

Intervention / Treatment
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* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients age 65 or older who underwent induction of general anesthesia at YNHH Only first surgery for each patient within the time period is counted Only include patients who underwent intubation Only include patients who underwent induction by propofol bolus Only include patients who got at least 0.3mg/kg of propofol Exclusion Criteria: Patients under the age of 65, patients who underwent monitored anesthetic care/conscious mediation for their procedures. Patients with renal failure and/or chronic kidney disease Patients who have a pre-operative systolic blood pressure <100

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 65-75 years of age<br>Patients who are between the ages of 65 and 75, including 65 but not including 75, and receive propofol for induction of anesthesia. | Drug: Propofol<br>* Induction of anesthesia prior to surgery with propofol<br>* Other names: Diprivan;|
| 75-85 years of age<br>Patients who are between the ages of 75 and 85, including 75 but not including 85, and receive propofol for induction of anesthesia. | Drug: Propofol<br>* Induction of anesthesia prior to surgery with propofol<br>* Other names: Diprivan;|
| 85+ years of age<br>Patients who are 85 years of age or older, and receive propofol for induction of anesthesia. | Drug: Propofol<br>* Induction of anesthesia prior to surgery with propofol<br>* Other names: Diprivan;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overdose | Percentage of patients >=65 who received greater than the FDA approved induction dosage of propofol | Between time of induction of anesthesia and surgical incision as detailed in the patient's anesthesia record | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hypotension | Mean arterial pressure of less than 60mmHg | Between time of induction of anesthesia and surgical incision as detailed in the patient's anesthesia record | 
| Acute kidney injury | AKI identifies when there is an increase of 1.5 times the baseline serum creatinine observed in first 7 postoperative days OR when the baseline creatinine increases greater than or equal to 0.3 mg/dl in 48 hours after anesthesia end. Baseline serum creatinine is defined as the most recent serum creatinine resulted in the last 60 days preoperatively. | Within 7 days postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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acute kidney injury, hypotension, anesthetic dosing, induction, elderly