Serratus Anterior Block and Catheter Use in Rib Fractures in the Emergency Department

SABRE: Serratus Anterior Block and Catheter Use in Rib Fractures in the Emergency Department

The main aim of this study is to determine whether Serratus Anterior Plane (SAP) blockade provides improved pain relief after rib fractures compared to epidural administration of local anaesthetic. The investigators aim to show that SAP catheters (SAPC) can be placed in more situations and are less operator-dependent then thoracic epidural anaesthesia (TEA). This reduces the waiting time required to achieve satisfactory analgesia in the patient. Optimal analgesia allows early respiratory physiotherapy and reduction in the complications of multiple rib fractures.

Pain from rib fractures is severe. The sensory nerves of the thoracic wall lie in the SAP and a single ultrasound-guided injection of local anaesthetic spreads widely and provides useful post-injury analgesia for several hours. If a catheter is left in the SAP, the nerve blockade can be maintained for several days.

Rib Fracture pain is traditionally treated with oral/ intravenous analgesics or TEA. Opiate analgesia via patient controlled analgesia (PCA) can work very well but it is associated with excessive sedation, constipation, nausea and vomiting. Continuous TEA is generally regarded as the gold standard but it demands monitoring by adequately trained ward staff and is commonly associated with high failure rates and increased risk of complications. SAPC has also been used when TEA and PCA were not desirable.

The primary outcome will be the amount of morphine analgesia required by the patient. Secondary outcomes will be pain scores (at rest and on movement), the side effects of morphine, complications of TEA/ SAPC, respiratory function changes and a quality of recovery assessment.

The control group will have an epidural block and catheter placed. The treatment group will have SAP blocks and catheters placed under ultrasound guidance. Both blocks will be tested to ensure good pain relief. To avoid potential confounding effects, oral painkillers will adhere strictly to the study protocol.

Inclusion Criteria:

• Patients aged over 18 years suffering 2 or more rib fractures

Exclusion Criteria:

1. Significant renal dysfunction (baseline creatinine >150μmol/l - morphine contra- indicated)
2. Pregnancy
3. Patients with chronic pain on regular analgesic medication
4. Patients with significant coagulation abnormality (unsafe to site blocks)
5. Participation in another interventional study that will interact with this trial.
6. Patients unable to give informed consent
7. Hypersensitivity to local anaesthetic (or any other study drug).
8. Contraindication to NSAID (peptic ulceration or sensitive asthma)
9. Weight <50kg