Minimum Effective Intrathecal Dose of Local Anaesthetic With Fentanyl for Fractured Neck of Femur(Dose Finding Study).

February 2, 2015 updated by: tomas hitka, Cork University Hospital

Determination of the Initial Minimum Effective Dose of 0.5% Bupivacaine With 20mcg of Fentanyl Via a Spinal Catheter for Operative Fixation of Fractured Neck of Femur.

Fractured neck of femur (FNF) is a common cause of admission to hospital in elderly patients with multiple comorbidities. Anaesthetic management of this patient group is extremely challenging.Neuraxial anaesthesia with minimum doses of local anaesthetic agents administered via a spinal catheter leads to better cardiovascular stability.The minimum dose of local anaesthetic with intrathecal fentanyl was not established yet.We propose to study and determine the initial minimum local anaesthetic dose (MLAD) of 0.5% bupivacaine with 20 mcg of fentanyl administered via a spinal catheter to achieve a sensory block up to T10 for the operative fixation of FNF.We will use a previously well established Dixon and Massey "up-and-down method" to calculate initial MLAD in this prospective, observational trial.

Objectives: We would like to determine the initial MLAD of 0.5% bupivacaine with 20mcg of fentanyl administered via a spinal catheter required to achieve a sensory block up to T10 on the side of FNF.

Outcomes

Primary outcome:

  1. Initial MLAD of 0.5% bupivacaine with 20mcg of fentanyl required for a sensory block up to T10 on the side of FNF.

    Secondary outcomes:

  2. Total dose of 0.5% bupivacaine with 20mcg of fentanyl required for the operative fixation of fractured neck of femur.
  3. The effect on haemodynamic variables (blood pressure, heart rate).
  4. Incidence of side effects
  5. The length of postoperative analgesia (the time from the last dose of local anaesthetic administered intrathecally to VAS>3).
  6. The time to first rescue analgesic requirement

Study Design Prospective, observational trial.

Study Size Based on the previously well established Dixon and Massey "up-and-down method"(10), we will recruit patients until a successful spinal block has been achieved in six consecutive patients who received a specific dose. This is the requirement to calculate the initial MLAD.

Study Overview

Study Type

Observational

Enrollment (Actual)

33

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Cork, Ireland, 00000
        • Cork University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

60 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

patients with fractured neck of femur undergoing surgical repair of their fracture

Description

Inclusion Criteria:

  • fractured neck of femur
  • Above 60 years
  • American Society of Anesthetists(ASA) I to III

Exclusion Criteria:

  • Patient refusal
  • Outside Age Range
  • Contraindications to spinal anaesthesia
  • Head injury or other associated injuries
  • Loss of consciousness and signs of acute coronary syndrome
  • Mini-Mental Score < 25 (Appendix 2)
  • Allergy to bupivacaine, lignocaine or fentanyl

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Bipolar hemiarthroplasty.
Group of patients who will stay in lateral position during whole surgery.
Dynamic hip screw.
Group of patients who will be supine during surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Initial MLAD of 0.5% bupivacaine with 20mcg of fentanyl required for a sensory block up to T10 on the side of FNF
Time Frame: 15min
A blinded observer will assess the dermatome level of sensory blockade with an ice-cold test (ethyl-chloride spray) bilaterally after the injection of the local anaesthetic. Block assessment will be performed every 5min up to 15 min after completion of the initial intrathecal injection. Sensory block up to T10=positive result Sensory block below T10=negative result.
15min

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total dose of 0.5% bupivacaine with 20mcg of fentanyl required for the operative fixation of fractured neck of femur
Time Frame: Duration of surgery.
Initial dose and all top ups will be recorded and analysed in conjunction with the length of surgery and surgical procedure used to fix FNF.
Duration of surgery.
The effect on haemodynamic variables (blood pressure, heart rate).
Time Frame: Duration of surgery.
Noninvasive automated blood pressure and heart rate measurements will be recorded before the spinal anaesthesia (baseline) and every three minutes after the end of local anesthetic injection until the end of surgery.Hypotension is defined as a decrease of more than 20% from the baseline systolic arterial blood pressure (SAP). Severe hypotension is defined as a decrease in SAP more than 30% of baseline value. Hypotension will be treated with IV boluses of ephedrine 6 mg if the heart rate is below 60/minutes or phenylephrine 100 mcg if the heart rate is above 60/minutes.The number of hypotensive episodes, a total amount of vasopressor administered, and the i.v. fluid infused will be recorded as well as duration of anaesthesia.
Duration of surgery.

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of side effects.
Time Frame: 24-48 hours
Patients will be interviewed 24-48 hours after surgery regarding side effects of spinal anaesthesia (headache, pruritus,postoperative nausea and vomiting,urinary retention,neurological deficit)
24-48 hours
The length of postoperative analgesia (the time from the last dose of local anaesthetic administered intrathecally to VAS>3).
Time Frame: 1-2 hours
The time from the last top up of local anaesthetic to VAS >3 and to the first dose of break through analgesia will be recorded.
1-2 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Tomas Hitka, RA fellow, Cork University Hospital
  • Study Chair: Gabriella Iohom, consultant, Cork University Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

July 1, 2013

Primary Completion (Actual)

June 1, 2014

Study Completion (Actual)

June 1, 2014

Study Registration Dates

First Submitted

August 12, 2013

First Submitted That Met QC Criteria

August 12, 2013

First Posted (Estimate)

August 14, 2013

Study Record Updates

Last Update Posted (Estimate)

February 4, 2015

Last Update Submitted That Met QC Criteria

February 2, 2015

Last Verified

February 1, 2015

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Minimum Effective Dose of Local Anaesthetic With Fentanyl

3
Subscribe