Plain English Summary
Background and study aims
The aim of this study is to find out whether injecting a local anaesthetic into the back to block the nerves to the chest (a paravertebral injection) reduces pain after cardiac surgery. This is a technique of pain control the trialistshave been using recently and it sounds sensible, but it’s hard to be sure that it really works because there are such big differences in the amount of pain people experience after cardiac surgery. What’s more, just getting local anaesthetics into the blood stream reduces pain after other surgical operations, so it may be that paravertebral injections are working simply because the drug is being absorbed into the blood. This study is designed to clarify the situation.
Who can participate?
Patients undergoing coronary artery bypass grafting.
What does the study involve?
Patients are randomly allocated into one of two groups. Those in group 1 are given bilateral paravertebral blocks during surgery. Those in group 2 are given a dummy, or 'sham', injection under the skin. After surgery, patients are able to self-administer pain relief (morphine) as they need it, to see whether the patients with true paravertebral injections want less morphine than those with the sham injections.
What are the possible benefits and risks of participating?
It is hoped that all patients taking part get additional benefit from the local anaesthetic infusion. The catheters are placed under the same rigorous aseptic conditions as the rest of their surgery so no infections are expected.
Where is the study run from?
Hammersmith Hospital (UK)
When is study starting and how long is it expected to run for?
October 2014 to September 2016
Who is funding the study?
Imperial College Healthcare NHS Trust (UK)
Who is the main contact?
Dr Geoff Lockwood
Dr Geoff Lockwood
A double blind, randomised controlled trial to assess the efficacy of bilateral paravertebral blockade for analgesia after cardiac surgery
Do paravertebral blocks provide useful analgesia by blocking specific nerves or are we simply seeing the systemic effects of the local anaesthetics as they are absorbed into the circulation?
London (Dulwich), 08/08/2014, ref: 14/LO/0864
Single centre interventional randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet
Bilateral paravertebral blockade or sham infusion of lidocaine
Primary outcome measure
Morphine consumption using a PCA device
Secondary outcome measures
1. Pain (measured using ordinal scale) and respiratory function (PEFR) for first 7 days
2. Quality of life, measured using the EuroQol EQ-5D questionnaire at 3 months
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Age 40-70 years
2. Undergoing elective and urgent first time coronary bypass surgery
Target number of participants
Participant exclusion criteria
1. Critical preoperative state
2. Single graft surgery (no leg incision)
3. Minimally invasive surgery (no sternotomy)
4. Significant renal disease (baseline creatinine >150 micromolar: morphine contraindicated)
5. Patients exceeding 110kg (4% of our operative population practical difficulties of positioning unconscious patients to place the block)
7. Patients with chronic pain taking regular analgesic medication
8. Patients with a significant abnormality of coagulation
9. Participation in another interventional study
10. Patients unable to give informed consent
11. Hypersensitivity to lidocaine
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Imperial College Healthcare NHS Trust
Funding Body Type
private sector organisation
Funding Body Subtype
Other non-profit organizations
Results and Publications
Publication and dissemination plan
Intention to publish date
Participant level data
Available on request
Basic results (scientific)
2017 results in: https://www.ncbi.nlm.nih.gov/pubmed/28592166