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The Effect of HPI to Reduce Intraoperative Hypotension in Caesarean Sections

The Effect Of Using Hypotension Prediction Index To Reduce Intraoperative Hypotension In Caesarean Sections: A Randomised Controlled Trial

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06892665
Enrollment
100
Registered
2025-03-25
Start date
2024-12-01
Completion date
2025-12-31
Last updated
2026-06-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cesarean Section Complications, Hypotension, Maternal-Fetal Relations, Pregnancy Related

Brief summary

During caesarean section, blood pressure variations especially a reduction in blood pressure (or hypotension) can bring harmful effects to mother and baby. This usually occurs after spinal anaesthesia is administered. Usually, the anaesthetist will treat hypotension as it occurs. However, a new medical device is now available to predict hypotension. It is called the Hypotension Prediction Index (HPI). This device allows the prediction of hypotension; hence, treatment can be given before it occurs. It has been widely utilised in major surgeries like abdominal tumour surgery and cardiac surgery worldwide and has shown a substantial reduction in hypotension. This study aims to determine whether the duration and severity of hypotension can be reduced when HPI is used in lower segment caesarean sections. The secondary objective of the study is to determine if the complication rate can be reduced in both mother and baby.

Detailed description

Hypotension Prediction Index (HPI) has been shown to reduce IOH significantly in non-cardiac and major abdominal surgeries.The role of HPI beyond reducing IOH has also been a subject of research. Andrzejeska et al. demonstrated that the use of HPI in adolescent idiopathic scoliosis surgery leads to lower reductions in post-surgery haemoglobin levels, shorter duration of hypotension and shorter hospital admissions. Additionally, the intervention group had shorter timeframes from the end of surgery to extubation. The development of a non-invasive finger blood pressure device compatible with HPI called the Acumen IQ cuff, made it possible to use HPI without inserting an arterial catheter. The arterial pressure waveform generated by a non-invasive finger cuff was reliable and in agreement with the radial artery blood pressure. A retrospective analysis was conducted by Frassanito et al. to determine the performance of HPI using arterial waveform recorded by a non-invasive finger probe to predict hypotension in patients undergoing CS under spinal anaesthesia. They have found that HPI, using this non-invasive probe, was able to predict hypotension with a sensitivity and specificity of 83% and 83% at 3 minutes, 97% and 97% at 2 minutes, and 100% and 100% at 1 minute, before it occurs. This study aims to determine if the solution to reduce IOH lies in predicting intraoperative hypotension during lower segment ceaserean section (CS). The benefits of HPI may extend beyond reducing the incidence and severity of IOH, to bringing positive outcomes to the foetus. This study will determine whether integrating an early warning system produces benefits significant enough to justify changing our anaesthetic practice. PROBLEM STATEMENT Varying methods have been utilised to reduce IOH in CS. A novel software, HPI, was developed to predict hypotension, enabling clinicians to institute guided treatment before maternal hypotension occurs. The investigator need to determine if HPI has benefits in CS, thus leading to better maternal and neonatal outcomes. RESEARCH QUESTION Can HPI using the non-invasive continuous arterial pressure waveforms reduce the duration and severity of hypotension in patients undergoing CS under spinal anaesthesia? OBJECTIVES Study objective: To determine if HPI has benefits in CS, thus leading to better maternal and neonatal outcomes compared to oNIBP. Primary outcome: The duration and severity of hypotensive events reported as a time-weighted average (TWA) - MAP \< 65 mmHg in HPI group (intervention) versus standard oNIBP. Secondary outcomes: 1. To determine whether the use of HPI leads to better maternal outcomes (incidence of nausea and vomiting, blood loss, length of hospital stay, maternal satisfaction, incidence of surgical site infection) 2. To determine whether the use of HPI leads to better foetal outcomes (Apgar scores, umbilical cord pH, length of hospital stay) 3. To determine the amount of vasopressors and inotropes administered throughout CS if HPI is used versus conventional oNIBP monitoring RESEARCH HYPOTHESIS Additional parameters from HPI in the CS under spinal anaesthesia will reduce the duration and severity of intraoperative hypotension and provide better maternal and neonatal outcomes.

Interventions

HPI and other haemodynamics parameters, is available to the anaesthetist to view and act upon

Anaesthetist will respond to hemodynamic variables using NIBP

Sponsors

National University of Malaysia
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)

Masking description

By computer randomisation, patients will be randomised into two groups, Group A (Intervention: HPI) or Group B (control: oNIBP). Standard monitoring will be applied, including a 3-lead electrocardiogram, pulse oximetry, and oNIBP in the upper arm. The oNIBP monitoring will be performed every 1 minute before, and every 3 minutes after the baby is delivered, up to 90 minutes of surgery duration. After 90 minutes, data collection will cease. In addition to the standard monitoring, all patients will have an Acumen IQ cuff placed on one of their fingers, as Appendix A shows, connected to haemodynamic monitoring using HemoSphere (Edwards Lifesciences) with HPI software enabled. In Group A, the Acumen IQ cuff, with HPI and other haemodynamics parameters, is available to the anaesthetist to view and act upon. While in Group B, the attending anaesthetist will be blinded from the HPI parameters.

Intervention model description

A prospective, double-blinded, randomised controlled trial

Eligibility

Sex/Gender
FEMALE
Age
18 Years to 40 Years
Healthy volunteers
No

Inclusion criteria

* ≥ 37 weeks of gestation * Elective CS * Age between 18 - 40 years old * Singleton pregnancy * Planned for spinal anaesthesia

Exclusion criteria

* American Society of Anesthesiologists (ASA) III and above * Body mass index (BMI) ≥ 40 kg/m2 * Increased risk of developing peripartum haemorrhage * History of peripartum haemorrhage * Placenta previa major, accrete, increta, percreta * Gravida ≥ 5 * Presence of large uterine fibroids * Congenital bleeding disorders such as Haemophilia A, Haemophilia B and Von Willebrand disease * Acquired bleeding disorders such as thrombocytopenia and coagulopathy * Contraindications to finger cuff orNIBP application, such as finger ischaemia, upper limb neurological deficit, discoloured nail * Cardiac arrhythmias and aortic regurgitation * Patient's refusal

Design outcomes

Primary

MeasureTime frameDescription
Time-weighted average of Mean arterial pressure <65mmHgFrom spinal anaesthesia to completion of surgeryCalculated using a formula. TWA-MAP \< 65 mmHg = (the depth of hypotension\< MAP of 65 mmHg x time spent below a MAP of 65 mmHg (minutes))/(total duration of operation (minutes))

Secondary

MeasureTime frameDescription
Incidence of nausea and vomiting,Perioperative up to 2 daysMaternal incidence of nausea and vomiting
length of hospital stayPerioperative up to 2 weeksmaternal length of hospital stay
maternal satisfactionPerioperative up to 2 weeksLikert scale from 1 (very unsatisfied) to 5 (very satisfied)
incidence of surgical site infectionPerioperative up to 2 weeksmaternal surgical site infection
Apgar score of feotal1 minute and 5 minutes after deliveryApgar scores of 0-10 ( Apgar score of 7 and more is considered normal)
Umbilical cord PHImmediately upon delivery of babyUmbilical cord PH taken after after delivery of baby
Neonatal length of stayPerioperative up to 2 weeksNeonatal length of stay

Countries

Malaysia

Contacts

PRINCIPAL_INVESTIGATORAzlina Masdar

National University of Malaysia

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 18, 2026