Physiological Reference Values of Total Arterial Impedance Derived From PRAM Monitoring

NCT07340333 | Completed

• 2 other identifiers: ATAUNI-PRAM-ZTOT-20262026/1
• Study Type: observational
• Target: 437
• Locations: 1 country
• Sites: 1

Brief Summary

Total arterial impedance (Ztot) is an advanced hemodynamic parameter that reflects the global arterial load opposing ventricular ejection by integrating both steady and pulsatile components of the arterial system. Although Ztot can be continuously derived from Pressure Recording Analytical Method (PRAM)-based monitoring, physiological reference values under stable clinical conditions are not well established. This observational study aims to define patient-level physiological reference values for Ztot using intraoperative hemodynamic data obtained from PRAM-based arterial waveform analysis during hemodynamically stable periods. In addition, the study evaluates the associations between Ztot and key hemodynamic variables reflecting arterial load and cardiovascular performance. High-resolution intraoperative data routinely recorded during standard clinical care are retrospectively analyzed. The findings of this study are intended to improve the interpretability of Ztot in advanced hemodynamic monitoring and to support future clinical and research applications.

Conditions

Intraoperative Hemodynamics

Keywords

Total arterial impedance; PRAM monitoring; Arterial load; Advanced hemodynamic monitoring; Pressure waveform analysis; Physiological reference values; Intraoperative hemodynamics

Outcome Measures

Primary Outcomes (1)

• Physiological reference interval of total arterial impedance (Ztot)

  Patient-level physiological reference interval (2.5th-97.5th percentiles) of PRAM-derived total arterial impedance (Ztot) calculated from intraoperative hemodynamic measurements obtained during predefined hemodynamically stable periods.

  Intraoperative period

Secondary Outcomes (2)

• Association between total arterial impedance and arterial load-related hemodynamic variables

  Intraoperative period

• Association between total arterial impedance and cardiovascular performance indices

  Intraoperative period

Study Arms (1)

Intraoperative PRAM Monitoring Cohort

Adult surgical patients with invasive arterial monitoring whose intraoperative hemodynamic data were retrospectively analyzed during predefined hemodynamically stable periods using PRAM-based waveform analysis.

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult surgical patients who underwent routine intraoperative invasive arterial monitoring, from whom PRAM-based hemodynamic data were retrospectively analyzed during predefined hemodynamically stable intraoperative periods.

You may qualify if:

• Adult patients (≥18 years) who underwent surgery with invasive arterial catheterization.
• Availability of intraoperative hemodynamic data recorded using PRAM-based arterial waveform monitoring.
• Presence of predefined hemodynamically stable intraoperative periods meeting physiological stability criteria.
• Adequate arterial waveform signal quality for PRAM-derived parameter analysis.

You may not qualify if:

• Age \<18 years.
• Inadequate arterial waveform signal quality or missing PRAM-derived data.
• Absence of intraoperative periods fulfilling predefined hemodynamic stability criteria.
• Incomplete or corrupted intraoperative monitoring records.

Sponsors & Collaborators

• Ataturk University: lead

Study Sites (1)

Ataturk University

Erzurum, 25240, Turkey (Türkiye)

Location

Related Publications (8)

• Vlachopoulos C, O'Rourke M, Nichols WW. McDonald's Blood Flow in Arteries: Theoretical, Experimental and Clinical Principles. 6 ed. Boca Raton, FL: CRC Press; 2011.

  BACKGROUND

• Kelly RP, Ting CT, Yang TM, Liu CP, Maughan WL, Chang MS, Kass DA. Effective arterial elastance as index of arterial vascular load in humans. Circulation. 1992 Aug;86(2):513-21. doi: 10.1161/01.cir.86.2.513.

  PMID: 1638719 BACKGROUND

• Kass DA. Ventricular arterial stiffening: integrating the pathophysiology. Hypertension. 2005 Jul;46(1):185-93. doi: 10.1161/01.HYP.0000168053.34306.d4. Epub 2005 May 23.

  PMID: 15911741 BACKGROUND

• Sunagawa K, Sagawa K, Maughan WL. Ventricular interaction with the loading system. Ann Biomed Eng. 1984;12(2):163-89. doi: 10.1007/BF02584229.

  PMID: 6507965 BACKGROUND

• Westerhof N, Lankhaar JW, Westerhof BE. The arterial Windkessel. Med Biol Eng Comput. 2009 Feb;47(2):131-41. doi: 10.1007/s11517-008-0359-2. Epub 2008 Jun 10.

  PMID: 18543011 BACKGROUND

• O'Rourke M, Adji A, Nichols WW, Vlachopoulos C, Edelman ER. Application of Arterial Hemodynamics to Clinical Practice: A Testament to Medical Science in London. Artery Res. 2017 Jun;18:81-86. doi: 10.1016/j.artres.2017.03.003. No abstract available.

  PMID: 29861794 BACKGROUND

• de Keijzer IN, Scheeren TWL. Perioperative Hemodynamic Monitoring: An Overview of Current Methods. Anesthesiol Clin. 2021 Sep;39(3):441-456. doi: 10.1016/j.anclin.2021.03.007. Epub 2021 Jul 12.

  PMID: 34392878 BACKGROUND

• Pinsky MR. Functional hemodynamic monitoring. Crit Care Clin. 2015 Jan;31(1):89-111. doi: 10.1016/j.ccc.2014.08.005.

  PMID: 25435480 BACKGROUND

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: January 6, 2026
• First Posted: January 14, 2026
• Study Start: January 30, 2026
• Primary Completion: February 2, 2026
• Study Completion: February 2, 2026
• Last Updated: February 4, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)