Analyzing Efficacy and Bias in Serratus Anterior Plane Block Research

Date: August 19, 2024 Reference: Partyka et al. Serratus Anterior Plane Blocks for Early Rib Fracture Pain Management: The SABRE Randomized Clinical Trial. JAMA Surg 2024 Guest Skeptic: Dr. Sean Baldwin is an Emergency Physician practising in Sydney, Australia in both a large tertiary emergency department and a small regional emergency department. Interests include information systems and digital health, research and education. Case: A 67-year-old male presents to your hospital emergency department (ED) after a fall from his bicycle. He has three left-sided rib fractures on imaging without underlying complications. He has severe pain with breathing and asks you what the best way to manage his pain may be. Background: Rib fractures are a common injury, particularly for those over 65. This is partly due to the natural aging process, which often leads to decreased bone density and increased fragility. Older people are more susceptible to fractures from even minor trauma. Rib fractures in this population are especially concerning because they are not only extremely painful but also associated with higher morbidity and mortality rates. The pain from rib fractures can lead to reduced mobility, impaired respiratory function, and an increased risk of complications such as pneumonia, making their management a critical aspect of care in older adults. We have covered rib fractures twice on the SGEM. SGEM episode #324 looked at using spirometry to guide discharging older patients with rib fractures. The evidence was not robust enough back in 2021 to confidently use this potential tool. More recently, the April 2024 SGEMHOP reviewed a trial on how effective and safe an ultrasound-guided erector spinae plane block (ESPB) in adult patients with rib fractures is. The bottom line from that episode was that clinicians with adequate training, ultrasound-guided ESPB can provide safe and effective pain control while achieving lower doses of opioid analgesia requirement for up to two hours after intervention.  Serratus anterior plane blocks (SAPBs) have been proposed as another potential effective treatment for pain control in patients with fractured ribs. This procedure involves the administration of a local anesthetic into the plane between the serratus anterior muscle and the rib cage, targeting the thoracic intercostal nerves that supply sensation to the chest wall. By blocking these nerves, SAPB provides substantial analgesia, helping to control pain and improve respiratory function without the systemic side effects associated with opioids. The block is typically performed under ultrasound guidance, which allows for precise placement of the anesthetic and minimizes the risk of complications. For elderly patients, particularly those with multiple rib fractures, SAPB can significantly enhance comfort and facilitate deeper breathing, potentially reducing the risk of pulmonary complications such as atelectasis or pneumonia. Clinical Question: Does the addition of a serratus anterior plane block to a protocolized bundle of care in the emergency department improve pain control? Reference: Partyka et al. Serratus Anterior Plane Blocks for Early Rib Fracture Pain Management: The SABRE Randomized Clinical Trial. JAMA Surg 2024 Population: Patients aged 16 years or older with clinically suspected or radiologically confirmed rib fractures. Exclusions: Patients intubated, pregnant, had received a prehospital SAPB, were transferred for urgent surgical intervention, had a moderate to severe traumatic brain injury, or had a major concomitant non-thoracic injury. Intervention: Serratus anterior plane block (SAPB) using ropivacaine in addition to the usual protocolized rib fracture management. Comparison: Standard protocolized rib fracture care alone without the SAPB. Outcome: Primary Outcome: Composite pain score reduction 4 hours after enrollment, defined as a reduction in the pain score by 2 or more p...