Comparison Bewteen Intraoperative HPI vs. High Mean Arterial Pressure Threshold

NCT ID: NCT06631482

Last Updated: 2025-12-17

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 100 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-09-16
• Study Completion Date: 2026-05-31

Brief Summary

Intraoperative hypotension (IOH) is a common and serious complication during surgery, closely associated with poor postoperative outcomes. Traditionally, anesthesiologists rely on real-time physiological parameters and alarms to monitor blood pressure, but the low alarm thresholds may lead to delayed interventions. The Hypotension Prediction Index (HPI) is a novel predictive tool that uses arterial waveform signals and advanced algorithms to forecast hypotensive events in advance. Recent observational studies have shown that HPI's accuracy in predicting hypotension is highly consistent with setting the physiological monitor's alarm threshold to 73 mmHg. This study will compare the effectiveness of HPI and a raised alarm threshold of 73 mmHg in preventing IOH. While HPI is promising with its AI-assisted approach to patient care, its high cost due to the advanced technology raises concerns. If its accuracy is comparable to simply raising the traditional monitor threshold, it may not lead to substantial changes in clinical practice.

Detailed Description

Intraoperative hypotension (IOH) is a significant complication that affects surgical patients, potentially leading to adverse outcomes postoperatively. Standard practices involve relying on monitoring devices with low alarm thresholds for blood pressure, which may result in delayed interventions. The Hypotension Prediction Index (HPI) offers a predictive approach by analyzing arterial waveform signals and using complex algorithms to detect potential hypotensive episodes early. Recent observational studies have suggested that HPI's accuracy in predicting hypotension aligns closely with raising the physiological monitor alarm threshold to 73 mmHg. To further investigate this, this study will compare the effects of setting a traditional monitor alarm threshold at 73 mmHg with using HPI to prevent IOH.

In this study, patients will be randomly assigned to two groups. In the HPI group, interventions will be initiated when the HPI value exceeds 85. These interventions will follow a protocol that includes fluid administration, norepinephrine, and dobutamine to prevent hypotension. The control group will have their alarm threshold set at 73 mmHg. For these patients, interventions will be based on stroke volume variation (SVV) and clinical judgment, utilizing fluid and norepinephrine as needed. HPI is an attractive AI-based tool for medical care, but its high cost due to advanced technology raises questions. If its accuracy proves to be similar to simply raising the alarm threshold to 73 mmHg, it may not lead to meaningful changes in clinical practice. The study aims to compare the efficacy of these two methods in reducing the incidence of IOH.

Conditions

Hypotension During Surgery

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: TRIPLE

Study Groups

HPI Group

Use the hypotension predictive index (HPI)-guided protocol to prevent intraoperative hypotension, initiating treatmentusing the fluid administration or intravenous norepinephrine infusion to keep intraoperative HPI below 85.

Group Type: EXPERIMENTAL

Maintain HPI < 85

Intervention Type: DEVICE

Protocolized treatment with fluid administration, norepinephrine, and dobutamine to prevent intraoperative hypotension. The two arms are triggered by different alarms: one from a traditional monitor with an elevated MAP threshold of 73 mmHg, and the other from an HPI threshold of 85.

73mmHg MAP Alarm Group

Intraoperative maintenance of the mean arterial pressure (MAP) at 73 mmHg or higher by using the fluid administration or intravenous norepinephrine infusion.

Group Type: ACTIVE_COMPARATOR

Maintain MAP>=73

Intervention Type: DRUG

Protocolized treatment with fluid administration, norepinephrine, and dobutamine to prevent intraoperative hypotension. The two arms are triggered by different alarms: one from a traditional monitor with an elevated MAP threshold of 73 mmHg, and the other from an HPI threshold of 85.

Interventions

Maintain HPI < 85

Protocolized treatment with fluid administration, norepinephrine, and dobutamine to prevent intraoperative hypotension. The two arms are triggered by different alarms: one from a traditional monitor with an elevated MAP threshold of 73 mmHg, and the other from an HPI threshold of 85.

Intervention Type: DEVICE

Maintain MAP>=73

Protocolized treatment with fluid administration, norepinephrine, and dobutamine to prevent intraoperative hypotension. The two arms are triggered by different alarms: one from a traditional monitor with an elevated MAP threshold of 73 mmHg, and the other from an HPI threshold of 85.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• A: Patients undergoing surgeries requiring general anesthesia lasting more than two hours, and requiring continuous arterial blood pressure monitoring via arterial catheter according to standard medical practice. This includes:

ASA Class II or higher. Estimated surgery duration of three hours or more. High cardiovascular risk, such as poorly controlled hypertension, diabetes, coronary artery disease, chronic kidney disease, or chronic emphysema.

• B: Patients aged 18 years or older.

Exclusion Criteria

• ASA Class I: Patients with mild systemic disease.
• Pregnancy: Pregnant women.
• End-stage renal disease: Patients with eGFR below 30 ml/min/1.73 m².
• Cardiac shunt: Presence of intracardiac shunt.
• Severe arrhythmias: Including supraventricular tachycardia (heart rate &amp;amp;gt;100 bpm), ventricular tachycardia, or ventricular fibrillation.
• Factors affecting SVV accuracy: Conditions such as atrial fibrillation (A-Fib) or thoracic surgery that can invalidate stroke volume variation (SVV) measurements.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

National Taiwan University Hospital

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Tsung Ta Wu, MD.

Role: PRINCIPAL_INVESTIGATOR

National Taiwan University Hospital Hsinchu branch

Locations

National Taiwan University Hosipital

Taipei, , Taiwan

National Taiwan University Hospital Hsin-Chu Branch

Taoyuan District, , Taiwan

Countries

Taiwan

References

Mulder MP, Harmannij-Markusse M, Fresiello L, Donker DW, Potters JW. Hypotension Prediction Index Is Equally Effective in Predicting Intraoperative Hypotension during Noncardiac Surgery Compared to a Mean Arterial Pressure Threshold: A Prospective Observational Study. Anesthesiology. 2024 Sep 1;141(3):453-462. doi: 10.1097/ALN.0000000000004990.

Reference Type: BACKGROUND

PMID: 38558038 (View on PubMed)

Hatib F, Jian Z, Buddi S, Lee C, Settels J, Sibert K, Rinehart J, Cannesson M. Machine-learning Algorithm to Predict Hypotension Based on High-fidelity Arterial Pressure Waveform Analysis. Anesthesiology. 2018 Oct;129(4):663-674. doi: 10.1097/ALN.0000000000002300.

Reference Type: BACKGROUND

PMID: 29894315 (View on PubMed)

Other Identifiers

202406137RIND

Identifier Type: -

Identifier Source: org_study_id