Inferior Vena Cava Collapsibility Index and Caval Aorta Index for Prediction of Hypotension General Anaesthesia

Accuracy of Preoperative Evaluation of Inferior Vena Cava Collapsibility Index and Caval Aorta Index for Prediction of Hypotension After Induction of General Anaesthesia: "A Prospective Observational Study"

1. To estimate sensitivity and specificity of preoperative IVCCI, max aortic diameter and IVC:Ao index as predictors of hypotension after induction of general anesthesia.
2. To compare accuracy of preoperative values of IVC: Ao index to preoperative IVCCI in prediction of hypotension after induction of general anesthesia.

Study Overview

• Status: Completed
• Conditions: IVC Collapsibility Index as Predictor for Hypotension

Detailed Description

After obtaining approval from the hospital ethics committee, informed consent will be obtained from 102 patients who will undergo elective surgery requiring general anaesthesia in supine position. Patients will be evaluated by history taking and proper examination. Pre-operative investigations will be checked. On the day of surgery, pre-operative fasting for 8 hours will be confirmed.

Upon arrival to the operating room, routine monitors in the form of pulse oximetry, electrocardiogarm and non-invasive blood pressure monitors will be applied. Intravenous line will be secured and routine premedications (ranitidine 50 mg and ondansetron 4 mg) will be administered.

1. IVC Ultrasonography (IVCCI and IVC:Ao index) :

   While the patient is lying supine, the IVC and aorta will be examined before induction of general anaesthesia using a curved ultrasound transducer set to abdominal mode with a B-mode scan (1-5 MHz; Acuson x300; Siemens Healthcare, Seoul, Korea).

   The transducer is placed in the subxiphoid region in a longitudinal position. IVC measurements are made just distal to the IVC-hepatic vein junction, approximately 3 to 4 cm distal to the right atrium. The IVC is identified by Doppler waveform, compressibility and phasic collapse with respiration. The maximum (IVCDmax) and minimum (IVCDmin) internal anteroposterior (AP) diameters of the IVC at the end of expiration and inspiration respectively over the same respiratory cycle will be measured. The IVCCI is derived from the equation: (7) IVCCI = [ (IVCDmax - IVCDmin) / IVCDmax ] X 100. To the left of the IVC, the abdominal aorta is visualized 10 mm above the coeliac trunk. The maximum internal AP diameter of the abdominal aorta is measured during systole. The IVC:Ao index is derived by taking the ratio of the maximum IVC diameter during expiration and the maximal abdominal aortic diameter during systole.

2. Induction of anesthesia:

Standard noninvasive monitoring including ECG, noninvasive blood pressure (BP) measurements every minute and oxygen saturation will be applied. Heart rate (HR), SBP and MBP will be recorded immediately before general anaesthesia and will be defined as baseline readings.

General anaesthesia induction will be started using propofol intravenous anaesthetic (2 mg/kg) and Fentanyl (1 microgram/kg) and Atracrurium non-depolarizing muscle relaxant (0.5 mg/kg).Smooth endotracheal intubation with appropriate sized-cuffed endotracheal tube will be done after 3 mins of manual bag mask ventilation. Confirmation of endotracheal intubation will be done by 3 successive capnography waves and by bilateral lung auscultation. Meanwhile, the noninvasive BP will be recorded immediately after induction, then 5 and 10 minutes post induction, with continuous monitoring of other vital parameters (HR and oxygen saturation) during the postinduction period.

Any episode of hypotension (defined as mean arterial pressure < 80% of the baseline reading or or MAP less than 60 mmHg) will be managed by ephedrine 5 mg every 2 min to increase SBP to 80% of the baseline or MAP more than 70 mmHg. If the hypotensive episode persisted for 2 minutes, another bolus of norepinephrine will be administered. Any episodes of bradycardia (defined as heart rate less than 50 bpm) will be managed by atropine (0.01 mg/kg).

Patients will then be divided into two groups depending on whether they'll develop post general anesthesia induction hypotension or won't. Any complications, such as hypoxia or allergic reaction will be noted and managed accordingly.

The attending anesthesiologist who will perform the induction of general anaesthesia and monitor the patient during the study period will be blinded to the ultrasound measurements of IVCCI and IVC :Ao index recorded pre-operatively.

Measurement tools

• Mean arterial blood pressure will be measured in supine position in one of the upper limbs in the operating room at 1-minute intervals starting from the baseline preoperative reading until skin incision as follows: 1-minute post-induction reading, 2-minutes post-induction reading, pre-intubation reading & post-intubation readings until skin incision. Taking in consideration that the maximum time for recording the readings of the blood pressure is 15 minutes because if hypotension occurred after this time it is unlikely to be due to the effect of induction of anesthesia.
• Heart rate will be recorded at 1-minute intervals starting from the baseline pre-operative reading until skin incision as follows: 1-minute post-induction reading, 2-minutes post-induction reading, pre-intubation reading & post-intubation readings until skin incision.
• Demographic data: (age - gender - comorbidities - current medications).
• The incidence of post-induction hypotension.
• The incidence of bradycardia.

• Study Type: Observational
• Enrollment (Actual): 120

Contacts and Locations

Study Locations

• Egypt
  • Cairo, Egypt, 11562
    • Kasr Alainy Hospitals

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients aged 18 - 60 years old , Patients undergoing elective surgery under general anesthesia, ASA I, II

Description

Inclusion Criteria:

• Patients aged 18 - 60 years old
• Patients undergoing elective surgery under general anesthesia.
• ASA I, II

Exclusion Criteria:

• Patients with BMI more than 35.
• Pregnant patients
• Emergency cases
• Patients with a baseline arterial SBP less than 90 mmHg or mean arterial pressure (MAP) less than 70 mmHg.
• Patients with major severe vascular disease, Unstable angina, Ejection fraction< 40 %, Respiratory distress, Implanted pacemaker or Patients on angiotensin converting enzyme inhibitors or angiotensin receptor blockers
• Patients with increased intra-abdominal pressure

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area under receiver operating characteristic curves (AUROC) of the preoperative IVCCI inprediction of post-induction hypotension	Area under receiver operating characteristic curves (AUROC) of the preoperative IVCCI inprediction of post-induction hypotension	5 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlation between each of maximum aortic diameter with the percentage of themaximum decrease in mean arterial pressure after induction of anesthesia	Correlation between each of maximum aortic diameter with the percentage of themaximum decrease in mean arterial pressure after induction of anesthesia	5 minutes
Correlation between each of IVC collapsibility index with the percentage of themaximum decrease in mean arterial pressure after induction of anesthesia	Correlation between each of IVC collapsibility index with the percentage of themaximum decrease in mean arterial pressure after induction of anesthesia	5 minutes

Collaborators and Investigators

• Sponsor: Cairo University
• Investigators: Study Director: Heba Omar, associate professor of anesthesia and surgical ICU, faculty of medicine, Cairo university

Publications and helpful links

General Publications

• Zhang J, Critchley LA. Inferior Vena Cava Ultrasonography before General Anesthesia Can Predict Hypotension after Induction. Anesthesiology. 2016 Mar;124(3):580-9. doi: 10.1097/ALN.0000000000001002.
• Salama ER, Elkashlan M. Pre-operative ultrasonographic evaluation of inferior vena cava collapsibility index and caval aorta index as new predictors for hypotension after induction of spinal anaesthesia: A prospective observational study. Eur J Anaesthesiol. 2019 Apr;36(4):297-302. doi: 10.1097/EJA.0000000000000956. Erratum In: Eur J Anaesthesiol. 2019 Nov;36(11):888.

Study record dates

Study Major Dates

• Study Start (Actual): May 30, 2022
• Primary Completion (Actual): July 25, 2022
• Study Completion (Actual): July 27, 2022

Study Registration Dates

• First Submitted: May 6, 2022
• First Submitted That Met QC Criteria: May 6, 2022
• First Posted (Actual): May 10, 2022

Study Record Updates

• Last Update Posted (Actual): July 29, 2022
• Last Update Submitted That Met QC Criteria: July 27, 2022
• Last Verified: July 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension
• Other Study ID Numbers: MD-266-2020

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

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