Role of Inferior Vena Cava Dispensability Index in Predicting Hypotension of Cement Syndrome in Hip Replacement Surgery Under General Anaesthesia

The aim of the study is to evaluate ICV distensibility index for predicting the incidence of hypotension following cementation in orthopedic hip replacement surgery in patient undergoing general anaesthesia

Study Overview

• Status: Active, not recruiting
• Conditions: Hypotension and Shock; Cement Syndrome
• Intervention / Treatment: Device: Ultrasound measurement of IVC

Detailed Description

Preoperative Settings:

Patients scheduled for elective hip replacement surgeries involving cementation at Ain Shams University Surgery Hospital will be identified and those meeting the inclusion criteria will be approached and enrolled after providing informed consent.

Patients will be confirmed to have fasted for 8 hours before surgery. Medical history will be taken, examinations performed, and laboratory results will be reviewed. A wide bore intravenous line (18-gauge) will be secured, and standard monitoring (ECG, blood pressure measurement, and pulse oximetry) will be applied.

Baseline blood pressure, heart rate, and mean arterial pressure will be recorded.

Intraoperative procedure:

To induce general anaesthesia, we will be using fentanyl (1-2 μg/kg), propofol (1.5-2 mg/kg) and non-depolarizing muscle relaxants (rocuronium or cis-atracurium) according to age, weight, chronic organ function and the needs of the surgery.

All patients are monitored continuously using ECG, pulse oximetry and capnography starting from the beginning of manual ventilation. Ventilatory parameters adjusted to PCO2 <40 mmHg (respiratory rate 12 breaths per minute,), with a tidal volume of 6 to 8 ml/kg, positive end-expiratory pressure (PEEP) of 6 cmH2O and inspired oxygen fraction (FiO2) of 50.

Noninvasive blood pressure measurements (mean arterial pressure (MAP) are obtained at 10 min intervals although the operation, an additional measurement is obligatory 2 min after induction, drug administration and during measurement of IVC-DI and 5 min pre- and post-cementing for 15 min, all measurements will be performed in the semi-recumbent position (head elevated 30°).

The inferior vena cava will be visualized in B-mode using ultrasound machine with Low-frequency curvilinear probe (2-5 MHz) or phased-array probe while patient in supine position the probe will be placed in subxiphoid (subcoastal) area, just below the sternum (from a longitudinal paramedian subxiphoid view). IVC can be differentiated from the aorta utilizing pulse wave Doppler. With M-mode imaging, done 2 to 3 cm distant to the right atrium, The last section of the vein, which is proximal to the hepatic vein inflow and 0.5-3 cm from the right atrium, will be selected, with Use of the callipers to measure the maximum IVC diameter (Dmax) during inspiration and the minimum IVC diameter (Dmin) during expiration. Then the IVC distensibility index is calculated and recorded using the formula: IVC distensibility index = [(maximum diameter on inspiration-minimum

diameter on expiration)/minimum diameter on expiration (Lujan Varas et al, 2015). All IVC measurements are taken post intubation 3 times and the mean value recorded. Patients will be divided into two groups.

Group A: those who develop hypotension post cementation. Group B: those who do not develop hypotension post cementation. In the study Hypotension will be defined as MAP < 60 mmHg or a decrease in SBP by > 20% from baseline. In case of persistent mean arterial pressure less than 55 mmHg, a 6 mg dose of ephedrine will be titrated. After two doses of ephedrine, another fluid bolus of 5 ml/kg will be given, followed by another dose of ephedrine until hypotension is corrected.

The primary outcome:

Cut off value of IVC-DI at which we can predict the incidence of hypotension following cementing in orthopedic surgery.

Secondary outcomes Intra-operative hemodynamic, the need of vasoactive drug administration, and the amount of fluid administered.

• Study Type: Observational
• Enrollment (Estimated): 30

Contacts and Locations

Study Locations

• Egypt
  • Abbassia
    • Cairo, Abbassia, Egypt, 00202
      • Ain Shams University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients will be selected from primary care clinic who are scheduled for Hip Replacement Surgery

Description

Inclusion Criteria:

• participants must be 18 years of age or older and provide written consent. Patients scheduled for elective hip replacement surgery under general anaesthesia with an American Society of Anesthesiologists (ASA) physical status of I or III based on preoperative assessment.

Exclusion Criteria:

• ▪ Patient refusal to participate.

  • ASA status IV or above.
  • Patients with BMI more than 30 kg/m².
  • Pre-existing hypotension, cardiac disease (such as heart failure or coronary artery disease), pulmonary disease (such as chronic obstructive pulmonary disease), renal disease (such as chronic kidney disease), hepatic disease (such as cirrhosis), coagulopathy or bleeding disorders, pregnancy or lactation, severe intra-operative blood loss requiring blood transfusion.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cut off value of IVC-DI at which we can predict the incidence of hypotension following cementing in orthopedic surgery.	Cut off value of IVC-DI at which we can predict the incidence of hypotension following cementing in orthopedic surgery.	All IVC measurements are taken 10 minutes post intubation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intra-operative hemodynamic(blood pressure)	In the study Hypotension will be defined as MAP < 60 mmHg or a decrease in SBP by > 20% from baseline.	At 10 minutes intervals all through the operation, an additional measurement is obligatory 2 minutes after induction, drug administration and during measurement of IVC-DI and 5 minutes pre- and post-cementing for 15 minutes
The need of vasoactive drug administration	In case of persistent(>5minutes) mean arterial pressure less than 55 mmHg, a 6 mg dose of ephedrine will be titrated.	Post cement insertion for 30 minutes
The Amount of Fluid administered.	After two doses of ephedrine, another fluid bolus of 5 ml/kg will be given, followed by another dose of ephedrine until hypotension is corrected.	Post cement insertion for 30 minutes

Collaborators and Investigators

• Sponsor: Ain Shams University
• Investigators: Study Director: Azza Mohamed Lotfy Youssef Nasr, Assistant Professor Phd, Ain Shams University; Study Director: Aya Ali Mahmoud Bayoumy, Lecturer Phd, Ain Shams University

Study record dates

Study Major Dates

• Study Start (Actual): December 20, 2025
• Primary Completion (Estimated): June 20, 2026
• Study Completion (Estimated): June 20, 2026

Study Registration Dates

• First Submitted: May 20, 2026
• First Submitted That Met QC Criteria: June 22, 2026
• First Posted (Actual): June 25, 2026

Study Record Updates

• Last Update Posted (Actual): June 25, 2026
• Last Update Submitted That Met QC Criteria: June 22, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Hypotension; Shock
• Other Study ID Numbers: MS 724/2025

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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