Effectiveness of Peripheral Nerve Blocks for the Treatment of Primary Headache Disorders: A Systematic Review and Meta-Analysis

Current practice for primary headache disorders and perspectives on peripheral nerve blocks among emergency physicians in Canada: A national survey

“…This contradicts with an existing systematic review which found a reduction of 1.5 points (interquartile range [IQR] = 1.1–2.1) as the absolute minimum clinically important difference for mixed patients in the ED for pain relief 26 . Whereas a three or four point reduction in pain may not be possible based on current evidence, which shows PNBs as improving pain by approximately one point at 15 and 30 min, pain relief is subjective and PNBs may accelerate pain relief while minimizing the need for pharmacotherapies which have known side effects 17 . Improvement in pain scales should not be the only metric for discharging patients home because this is subjective and will vary from patient to patient.…”

“…When emergency physicians were asked which type of PNB they would prefer for each type of headache, the majority would consider the occipital nerve block or trigger point injection for tension‐type headaches, and less than half would consider a PNB for migraine headaches; physicians typically would not consider a PNB for cluster headaches. Migraine attacks are the most prevalent form of primary headache presentation to the ED, thus most trials recruit patients with only migraine 17 ; however, PNBs may be effective for acute headache pain in general. For example, the SPG is a large extracranial parasympathetic ganglion which plays a vital role in controlling pain stimuli, or nociception, of the head and face region, due to its association with the trigeminal nerve.…”

“…An important consideration for physicians with treatment of headache pain is a clinically significant improvement for safe dis- approximately one point at 15 and 30 min, pain relief is subjective and PNBs may accelerate pain relief while minimizing the need for pharmacotherapies which have known side effects. 17 Improvement in pain scales should not be the only metric for discharging patients home because this is subjective and will vary from patient to patient.…”

“…Peripheral nerve blocks (PNBs), including the occipital nerve block, sphenopalatine ganglion (SPG) block, and trigger point injections are minor bedside procedures which involve administration of a small volume of a local anesthetic agent to promote neural blockade and break the pain cycle 16 . Based on current evidence, PNBs are effective compared to placebo at 1, 5, 15, and 30 min for primary headaches and should be considered as an adjunct therapy; however, there is insufficient evidence to determine if PNBs can be used as a first‐line alternative 17 . PNBs are currently understudied and the Canadian Headache Society only provides a weak recommendation for their use due to insufficient evidence 18 .…”

“…16 Based on current evidence, PNBs are effective compared to placebo at 1, 5, 15, and 30 min for primary headaches and should be considered as an adjunct therapy; however, there is insufficient evidence to determine if PNBs can be used as a first-line alternative. 17 PNBs are currently understudied and the Canadian Headache Society only provides a weak recommendation for their use due to insufficient evidence. 18 The frequency of use and emergency physician attitudes toward use of PNBs across Canada is currently unknown.…”