Prospective Trial of Alerting to Extended Hypotensive Exposures on Long-Term Outcome After Surgery (SLUScore™)

Prospective, Randomized Trial of Alerting to Extended Hypotensive Exposures on Long-Term Outcome Following Adult Non-Cardiac Surgical Procedures: The SLUScore™ Trial

Patients undergoing anesthesia for non-cardiac surgery will be randomized to either having their anesthesia team alerted or kept blinded to extended periods of less than normal blood pressure with the goal of studying if providing these alerts leads to improved outcome after surgery (lower risk of death or complication in the days and weeks following surgery).

Study Overview

• Status: Withdrawn
• Conditions: Hypotension; Anesthesia
• Intervention / Treatment: Behavioral: Electronic alert to SLUScore increase

Detailed Description

Background:

We recently identified a significant association of postoperative morbidity and 30-day mortality with the concept of "hypotensive exposures" during anaesthesia. Specifically, we found in approximately 160,000 patients from 3 institutions (Cleveland Clinic, Vanderbilt University and Saint Louis University) that roughly every third adult patient undergoing a non-cardiac procedure under anaesthesia experienced twice the 30-day all-cause mortality portended by extended cumulative periods of less than normal intraoperative blood pressure. This association was independent of co-morbidity (Charlson Co-morbidity index), causing the same relative increase in mortality in "healthy" as in "sick" patients. A new method was introduced to quantify hypotensive exposures in form of a novel risk score called the SLUScore™, a score with values from ranging from 0 (no hypotensive exposure) to a maximum of 31 (the maximal number of exposures exceeded of a certain risk-based set of limits for time accumulated at a mean arterial blood pressure below thresholds between 75 and 45 mm Hg), with each increment of the SLUScore™ portending an equivalent 5% increase in 30-day postoperative mortality.

Hypothesis:

We test the hypothesis that alerting the anaesthesia care team to progressive hypotensive exposures (a progressive increase in their SLUScore™) improves 30-day survival. This will be tested in a prospective, randomised trial.

Methods and Design:

A novel Clinical Decision Support System (ACG-Anesthesia by Talis Clinical, LLC) will be used to alert anaesthesia care team members to patients' SLUScores™ in near real time (within 1 minute of documented exposures). At the time of transition from a SLUScore™ of 0 to 1 (occurring in approximately every third anaesthetic), patients will be automatically randomized by the ACG-Anesthesia system to either alert or no alert (blinded) status with the intent of raising awareness on the part of the anaesthesia care team in the alert group of the occurrence of extended hypotensive exposures and their associated risk, allowing the team to render its best clinical judgment to initiate interventions aimed at bringing patients out of progressive hypotensive states. With one interim analysis planned after two years, a total of 56,248 patients are projected to be enrolled over a 4-year period for this trial to be powered to detect a 0.3% absolute reduction in 30-day mortality, by saving at least 50 lives in the alert group after two years (two-sided p<0.016) or at least 70 lives (two-sided p<0.019) at the conclusion of the trial.

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Saint Louis, Missouri, United States, 63110
      • Saint Louis University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Any adult patient presenting for any type of non-cardiac procedure performed under any type of anesthesia

Exclusion Criteria:

• Pediatric patients (< 18 yrs of age)
• Obstetric patients

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Electronic alert to SLUScore increase; Patients whose anesthesia care team members are receiving alerts to increments in their SLUScore (progressive hypotensive exposures) are anticipated to be given interventions aimed at minimizing further hypotensive exposures. The decision of whether or not to intervene as well as the type(s) of interventions will be at the sole discretion of the patient's anesthesia care team	Behavioral: Electronic alert to SLUScore increase; Treat hypotension to minimize further progression of the SLUScore; Other Names: Treat hypotension
No Intervention: Control (no alert); Routine anesthesia care at the discretion of the anesthesia care team

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
30-day all-cause postoperative mortality	This addresses the known rather high rate of death within 30 days following non-cardiac surgical or interventional procedures	30-days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite outcomes	Myocardial infarction; renal failure; septic shock	one week

Other Outcome Measures

Outcome Measure	Time Frame
Length of Hospital Stay	30 days

Collaborators and Investigators

• Sponsor: St. Louis University
• Investigators: Principal Investigator: Wolf H. Stapelfeldt, M.D., Saint Louis University School of Medicine

Publications and helpful links

Helpful Links

• Link to the full protocol on The Lancet's web site

Study record dates

Study Major Dates

• Study Start (Anticipated): July 1, 2018
• Primary Completion (Anticipated): July 1, 2022
• Study Completion (Anticipated): September 1, 2023

Study Registration Dates

• First Submitted: August 13, 2014
• First Submitted That Met QC Criteria: August 14, 2014
• First Posted (Estimate): August 15, 2014

Study Record Updates

• Last Update Posted (Actual): March 14, 2018
• Last Update Submitted That Met QC Criteria: March 12, 2018
• Last Verified: March 1, 2018

More Information

Terms related to this study

• Keywords: Hypotension; Anesthesia
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension
• Other Study ID Numbers: IRB # 24886

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No