The goal of this observational study is to learn about the long-term effects of the serratus anterior plane block (SAPB) in adult patients who suffered multiple unilateral anterolateral rib fractures within 24 hours of patient presentation to the emergency department. The main question it aims to answer is: Does the SAPB for multiple anterolateral rib fractures demonstrate reduction in patient morbidity and mortality, including incidence of pneumonia, length of hospital stay, discharge disposition, and death, as compared to standard analgesic regimens. The SAPB will be performed if a physician trained in the SAPB is available within 24 hours of injury. If a trained physician is not available and the patient meets inclusion criteria, they will receive parental analgesia with opioid therapy. They will be followed until date of hospital discharge, up until 60 days.