Abstract and Introduction
Systematic reviews associate peripheral nerve blocks based on anatomic landmarks or nerve stimulation with reduced pain and need for systemic analgesia in hip fracture patients. We aimed to investigate the effect of ultrasound-guided nerve blocks compared to conventional analgesia for preoperative pain management in hip fractures. Five databases were searched until June 2021 to identify randomised controlled trials. Two independent authors extracted data and assessed risk of bias. Data was pooled for meta-analysis and quality of evidence was evaluated using Grades of Recommendation Assessment, Development and Evaluation (GRADE). We included 12 trials (976 participants) comparing ultrasound-guided nerve blocks to conventional systemic analgesia. In favour of ultrasound, pain measured closest to two hours after block placement decreased with a mean difference of -2.26 (VAS 0 to 10); (p < 0.001) 95% CI [–2.97 to –1.55]. In favour of ultrasound, preoperative analgesic usage of iv. morphine equivalents in milligram decreased with a mean difference of –5.34 (p=0.003) 95% CI [–8.11 to –2.58]. Time from admission until surgery ranged from six hours to more than three days. Further, ultrasound-guided nerve blocks may be associated with a lower frequency of delirium: risk ratio 0.6 (p = 0.03) 95% CI [0.38 to 0.94], fewer serious adverse events: risk ratio 0.33 (p = 0.006) 95% CI [0.15 to 0.73] and higher patient satisfaction: mean difference 25.9 (VAS 0 to 100) (p < 0.001) 95% CI [19.74 to 32.07]. However, the quality of evidence was judged low or very low. In conclusion, despite low quality of evidence, ultrasound-guided blocks were associated with benefits compared to conventional systemic analgesia.
Hip fractures are a serious health problem. They are most common in the frail, elderly population and are associated with considerable pain in the perioperative stage. In addition to subjective discomfort, untreated pain may lead to increased risk of complications and delirium in this patient group.[1,2] Effective pain therapy is challenging, especially in this frail population with significant comorbidities. Conventional treatment with opioids and NSAIDs is associated with typical side effects and peripheral nerve blocks (PNBs) may not be effective because of the many nerves involved in pain transmission from the fractured area.
A recent Cochrane review concluded that PNBs performed perioperatively reduce pain on movement within 30 minutes after block placement, risk of acute confusional state and probably also reduce the risk of chest infection and time to first mobilisation. Likewise, other systematic reviews focusing on specific PNBs like the fascia iliaca compartment block and the femoral nerve block demonstrated pain reduction and reduced opioid consumption.[4,5] However, in these reviews the majority of included randomised controlled trials used PNBs without ultrasound (US)-guidance, i.e. they only used anatomic landmarks or nerve stimulation for guidance. It seems intuitive that using US-guidance should be more effective than using a blind technique, since it allows a trained physician to deposit the local anaesthetic (LA) with much more precision.
In this systematic review we therefore aimed to compare the analgesic effects of US-guided PNBs (US-PNBs) to conventional pain management with systemic use of analgesics. We hypothesised that US-PNBs reduce pain and opioid consumption prior to surgery compared to conventional pain management.
BMC Anesthesiol. 2022;22(192) © 2022 BioMed Central, Ltd.