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IVC Ultrasonography Versus Plethysmographic Variability Index for Prediction of General Anesthesia Induction Hypotension

Conditions
Hypotension on Induction
Interventions
Device: IVC Ultrasonography
Device: Plethysmographic variability index (PVI) and perfusion index readings (PI)
Registration Number
NCT04238234
Lead Sponsor
Cairo University
Brief Summary

This thesis aims to evaluate the ability of preoperative plethysmographic variability index to predict post-induction hypotension in comparison with ultrasound measurements of inferior vena cava (IVC) diameter.

Detailed Description

Prospective cohort study. Upon arrival to the operating room, routine monitors (ECG, pulse oximetry, and non-invasive blood pressure monitor) will be applied, intravenous line will be secured and routine premedications (ranitidine 50 mg and ondansteron 4mg) will be administrated.

Then inferior vena cava ultrasonography will be performed. Maximum and minimum IVC diameters over a single respiratory cycle will be measured using built-in software. The CI will be calculated as: CI = (dIVCmax - dIVCmin)/dIVCmax , it will be expressed as a percentage.

Plethysmographic variability index and a perfusion index readings will be taken preinduction in the form of three readings on one-minute interval.

Induction of anaesthesia will be achieved using propofol (2 mg/Kg) and atracurium (0.5 mg/Kg). Endotracheal tube will be inserted after 3 minutes of mask ventilation.

Anaesthesia will be maintained by isoflurane (1-1.5%) and atracurium 10 mg increments every 20 minutes. Ringer lactate solution will be infused at a rate of 2 mL/Kg/hour.

Any episode of hypotension (defined as mean arterial pressure \< 80% of the baseline reading) will be managed by 5mcg norepinephrine.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
90
Inclusion Criteria
  • Adult patients (>18years)
  • ASA I-II-III
  • Patients scheduled for elective surgeries under general anaesthesia.
Exclusion Criteria
  • Operations which will last for less than 15 minutes.
  • Patients with cardiac morbidities (impaired contractility with ejection fraction < 40% and tight valvular lesions, unstable angina).
  • Patients with heart block and arrhythmia (atrial fibrillation and frequent ventricular or supraventricular premature beat).
  • Patient with decompansted respiratory disease (poor functional capacity, generalized wheezes, peripheral O2 saturation < 90% on room air).
  • Patients with increased intraabdominal pressure (intrabdominal mass compressing IVC).
  • Patients with peripheral vascular disease or long standing DM affecting PVI readings.
  • Pregnancy

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
study groupPlethysmographic variability index (PVI) and perfusion index readings (PI)Participants will be adult patients (above 18 years), ASA I-II-III, scheduled for elective surgeries under general anesthesia.
study groupIVC UltrasonographyParticipants will be adult patients (above 18 years), ASA I-II-III, scheduled for elective surgeries under general anesthesia.
Primary Outcome Measures
NameTimeMethod
Comparison of the accuracy (Area under receiver operating characteristic curves) of PVI and IVC variation in prediction of post-induction hypotension10 minutes before general anesthesia

Maximum and minimum IVC diameters over a single respiratory cycle will be measured using a built-in software.

The CI will be calculated as:

CI = (dIVCmax - dIVCmin)/dIVCmax CI will be expressed as a percentage

Secondary Outcome Measures
NameTimeMethod
Heart rate20 minutes

measured at 1-minute intervals starting from the baseline preoperative reading until skin incision as follows: preinduction reading - 1-minute postinduction reading - 2-minute postinduction reading - preintubation reading - one-minute postintubation reading until skin incision

Mean arterial blood pressure20 minutes

measured at 1-minute intervals starting from the baseline preoperative reading until skin incision as follows: preinduction reading - 1-minute postinduction reading - 2-minute postinduction reading - preintubation reading - one-minute postintubation reading until skin incision

Maximum and minimum IVC diameters10 minutes

Maximum and minimum IVC diameters over a single respiratory cycle will be measured using built-in software. The CI will be calculated as:

CI = (dIVCmax - dIVCmin)/dIVCmax , it will be expressed as a percentage.

Plethysmographic variability index (PVI) and a perfusion index readings (PI)3 minutes

Three readings, on one-minute interval before general anesthesia induction

Trial Locations

Locations (2)

Kasr alainy

🇪🇬

Cairo, Egypt

Almaza Militrary Hospital

🇪🇬

Cairo, Egypt

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