Clinical Trial: Closed Loop Propofol Administration in Pediatric Cardiac Surgery

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Evaluation of Closed Loop Anaesthesia Delivery System for Propofol Anaesthesia in Pediatric Cardiac Surgery

Brief Summary: The purpose of the study is to evaluate and compare the feasibility, efficacy and safety of IAADS (Improved Anaesthetic Agent Delivery System) for propofol anaesthesia against manual control using bispectral index in paediatric patients undergoing open heart surgery under cardio-pulmonary bypass.

Detailed Summary:

Automated drug delivery has gained considerable interest in recent times. It is carried out by specially programmed electro-mechanical devices where dose rate adjustment is made independent of human intervention. The desired target is chosen by the clinician. The closed loop system depends upon a feedback signal to modify the rate of drug delivery. These have an advantage that they are able to overcome the individual pharmacokinetic and pharmacodynamic differences as well as the differing levels of surgical stimulation. Majority of studies on closed loop delivery of hypnotics has been done using propofol. CLADS(Closed loop anesthesia delivery system) is a BIS guided closed loop anaesthesia delivery system developed at PGIMER (Post graduate institute of medical education and research), Chandigarh and has been used successfully for administration of propofol in various situations, eg, non-cardiac surgery, cardiac surgery, post-operative sedation and high altitude. The system used will be IAADS, Improved anesthetic agent delivery system - the present and updated version of CLADS), a pharmacokinetic-pharmacodynamic model based adaptive system . There are only a few studies/reports regarding closed loop delivery of muscle relaxants in children. In this study, the efficacy of IAADS will be compared with manual control for administration of propofol using BIS as a control variable during induction and maintenance of anaesthesia in children undergoing elective open heart surgery.

After approval from the Institutional ethics committee and written informed parental consent, 40 children, aged 5-18 years and ASA physical status II-III, planned for elective open heart surgery under general anaesthesia will be studied. Patients will be randomly allocated to one of two groups - the manual group and the IAADS group using computer-generated random numbers in sealed opaque envelopes. Exclu
Sponsor: Postgraduate Institute of Medical Education and Research

Current Primary Outcome: Percentage of Time Bispectral Index(BIS) Remains+/-10 of Target [ Time Frame: Approximately 8 hours ]

The primary outcome to be measured is the ability of the system to keep the depth of anesthesia in the target range, i.e, Bispectral Index(BIS) value of 50+/- 10. This will assess the ability of the system to prevent intra-operative awareness of the patients and at the same time avoid excessive depth of anesthesia with its accompanying adverse effects.


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Median Performance Error(MDPE) [ Time Frame: Approximately 8 hours ]
    The difference between the observed and target of measure of depth of anesthesia (BIS) expressed as percentage of target BIS is calculated as performance error every 30 seconds. This value may be either '+' or '_' indicating whether the observed measure is above the target (overshoot-+) or below the target (undershoot-_). The median value of all performance errors during propofol anesthesia is median performance error and is a measure of bias of the system. This outcome is expressed as the mean of Median Performance Errors per participant.
  • Median Absolute Performance Error(MDAPE) [ Time Frame: Approximately 8 hours ]
    The difference between the observed and target of measure of depth of anesthesia (BIS) expressed as percentage of target BIS is calculated as performance error every 30 seconds. This value may be either '+' or '_' indicating whether the observed measure is above the target (overshoot-+) or below the target (undershoot-_).The median of the absolute values of performance errors (without considering the direction of error) is median absolute performance error. This outcome measures the magnitude of error or inaccuracy of the system studied. A lower value indicates a more precise system.This outcome is expressed as the mean of Median Absolute Performance Errors per participant.
  • Wobble [ Time Frame: Approximately 8 hours ]
    Wobble measures the intra-individual variability in performance error.The median of the difference between individual performance errors throughout anesthesia and the median performance error for each participant is the wobble of that participant. The mean value per participant is indicated in the outcome measure.
  • Percentage of Time Heart Rate Remains Within 25% of Pre-op Baseline [ Time Frame: Approximately 8 hours ]
    The duration of time heart rate remains within 25% of the pre-operative baseline value during the period propofol (general anesthetic) is administered to the study population. This value is expressed as a percentage. This outcome is expressed as the mean of percentage of time per participant.
  • Percentage of Time Mean Arterial Pressure Remains Within 25% of Pre-op Baseline [ Time Frame: Approximately 8 hours ]
    The duration of time mean arterial pressure remains within 25% of the pre-operative baseline value during the period propofol (general anesthetic) is administered to the study population. This value is expressed as percentage. This outcome is expressed as the mean of percentage of time per participant
  • Intra-operative Awareness [ Time Frame: Approximately 3 days and then 1 month later ]
    The number of patients who will be able to recall the intra-operative events when assessed postoperatively. This will be assessed by a structured protocol
  • Divergence [ Time Frame: 8 hours (approx) ]
    slope of the linear regression curve of performance error against time.
  • Global Score [ Time Frame: 8 hours (approx) ]
    overall performance assessment of the system calculated as= [(MDAPE+Wobble)/percentage of time BIS remains within target]x100 Lower score indicates better overall performance
  • Intraoperative Phenylephrine Used (Pre CPB) [ Time Frame: 2 hours(approx) ]
    total phenylephrine dose needed to be used in the pre CPB period to maintain hemodynamic stability


Original Secondary Outcome:

  • Median Performance Error(MDPE) [ Time Frame: Approximately 8 hours ]
    The difference between the observed and target of measure of depth of anesthesia (BIS) expressed as percentage of target BIS is calculated as performance error every 30 seconds. This value may be either '+' or '_' indicating whether the observed measure is above the target (overshoot-+) or below the target (undershoot-_). The median value of all performance errors during propofol anesthesia is median performance error and is a measure of bias of the system. This outcome is expressed as the mean of Median Performance Errors per participant.
  • Median Absolute Performance Error(MDAPE) [ Time Frame: Approximately 8 hours ]
    The median of the absolute values of performance errors (without considering the direction of error) is median absolute performance error. This outcome measures the magnitude of error or inaccuracy of the system studied. A lower value indicates a more precise system.This outcome is expressed as the mean of Median Absolute Performance Errors per participant.
  • Wobble [ Time Frame: Approximately 8 hours ]
    Wobble measures the intra-individual variability in performance error.The median of the difference between individual performance errors throughout anesthesia and the median performance error for each participant is the wobble of that participant. The mean value per participant is indicated in the outcome measure.
  • Percentage of Time Heart Rate Remains Within 25% of Pre-op Baseline [ Time Frame: Approximately 8 hours ]
    The duration of time heart rate remains within 25% of the pre-operative baseline value during the period propofol (general anesthetic) is administered to the study population. This value is expressed as a percentage. This outcome is expressed as the mean of percentage of time per participant.
  • Percentage of Time Mean Arterial Pressure Remains Within 25% of Pre-op Baseline [ Time Frame: Approximately 8 hours ]
    The duration of time mean arterial pressure remains within 25% of the pre-operative baseline value during the period propofol (general anesthetic) is administered to the study population. This value is expressed as percentage. This outcome is expressed as the mean of percentage of time per participant
  • Intra-operative Awareness [ Time Frame: Approximately 3 days and then 1 month later ]
    The number of patients who will be able to recall the intra-operative events when assessed postoperatively. This will be assessed by a structured protocol


Information By: Postgraduate Institute of Medical Education and Research

Dates:
Date Received: May 11, 2012
Date Started: January 2012
Date Completion:
Last Updated: July 10, 2013
Last Verified: July 2013