A pilot randomised clinical trial of 3-in-1 femoral nerve block and intravenous morphine as primary analgesia for patients presenting to the emergency department with fractured hip

Background: Fractured neck of femur (NOF) is a leading cause of morbidity and mortality in the elderly. Published clinical guidelines suggest early adequate analgesia as a key management aim. The femoral nerve '3-in-1 block' has previously been shown to provide effective analgesia for these patients in the periand post-operative phase of care. The aim of this study was to examine the use of the '3-in-1' femoral nerve block as primary analgesia for patients with a fractured NOF presenting to the emergency department. Methods: This was a single centre pragmatic randomised controlled open-label trial comparing femoral nerve block (using a '3-in-1' technique) with intravenous (IV) morphine. A convenience sample of patients presenting to the emergency department of a district general hospital with a clinically or radiologically suspected fractured NOF were recruited. They were randomised to receive either 0.1 mg/kg IV bolus of morphine or a '3-in-1' femoral nerve block with 30 ml of 0.5% plain bupivacaine. Visual analogue pain scores were noted prior to treatment and at 30 minutes, 2 hours, 6 hours and 12 hours after treatment. Immediate complications such as vascular puncture or the requirement for naloxone were noted. Results: Forty patients were recruited, 22 patients were randomised to IV morphine and 18 patients were randomised to '3-in-1' femoral nerve block. Complete data were available for 33 patients. There was no significant difference in initial median pain score (p=0.45). Analysis using the Wilcoxon test showed a significant decrease in pain score for the morphine group (p=0.01) and the nerve block group (p<0.01) at 30 minutes compared with baseline. Analysis using the Mann-Whitney U test between median pain scores at each time point showed a significant lower pain score in the nerve block group at 30 minutes (p=0.046). There were no immediate complications in either group. Conclusion: Our results suggest that a '3-in-1' femoral nerve