Hypotension Prediction 2 Study in Cardiac Surgery and Postoperative ICU Admission

Effect of a Machine Learning-Derived Early Warning System for Hypotension vs Standard Care on Depth and Duration of Intra- and Postoperative Hypotension in Elective Cardiac Surgery

This trial registration serves as an amendment incorporating the IPD Sharing Statement.

This study already has a trial registration (2021 April 30) in the Netherlands Trial Registry (Reference number NL9449, https://trialsearch.who.int/). However, the NTR register is subject to a merger with another Dutch register. This means that existing registrations are still visible, but can no longer be adjusted.

Study summary:

Hypotension in the operating room (OR) and during post-operative ICU admission is common in surgical patients and even more prevalent in cardiac surgery patients. It is associated with adverse outcomes and while these events are preventable, current management is predominantly reactive. Edwards Lifesciences (Irvine, CA) has developed the Hypotension Prediction Index (HPI), an early warning system that predicts an hypotensive event, defined as MAP below 65 mmHg, with high accuracy minutes before it occurs. At the time of writing the protocol this model has not been tested in a clinical trial in cardiac surgery patients or ICU admitted patients. The aim of the HYPE-2 trial is to assess whether the HPI-algorithm can reduce the time-weighted average (TWA) of intra- and postoperative hypotension in elective on-pump coronary artery bypass graft (CABG) surgery patients.

Population studied:

All adult patients undergoing elective on-pump CABG surgery or CABG with additional single heart valve surgery (e.g. valve repair or replacement), requiring a radial arterial line and an intended target MAP of 65 mmHg or above during both surgery (excluding cardiopulmonary bypass pump time (CBP)) and during mechanically ventilated phase of duration of ICU admission.

Inclusion Criteria:

• Aged 18 years or older at inclusion
• Planned for elective on-pump CABG surgery or CABG with additional single heart valve surgery (e.g. valve repair or replacement)
• Planned to receive standard monitoring for cardiac surgery
• Target MAP of 65 mmHg or above during surgery
• Target MAP of 65 mmHg or above during the mechanically ventilated phase of ICU admission

Exclusion Criteria:

• Known cardiac shunts (significant)
• Severe cardiac arrhythmias (including but not limited to persistent atrial fibrillation prior to surgery)
• Expected to receive an hemodynamic assist device (e.g. intra-aortic balloon pump) during surgery
• Dialysis dependent kidney failure prior to surgery
• Planned to receive Perioperative Goal Directed Therapy (PGDT) other than standard intraoperative care
• Previous cardiac surgery in medical history