The sphenopalatine ganglion (SPG) is an extracranial ganglion in the pterygopalatine fossa located posterior to the middle nasal turbinate and maxillary sinus and it contains sympathetic, parasympathetic and somatosensory nerves. The maxillary nerve, the 2ndbranch of the trigeminal nerve travels through the SPG and gives sensory innervation to parts of the pharynx, soft palate and nasal mucosa. Sympathetic fibers travel though SPG to lacrimal gland and nasal mucosa and parasympathetic nerves synapse in the SPG and innervate nasal, oral and pharyngeal membranes. It can be block by transcutaneous, transoral and transnasal routes. The transnasal topical approach is the easiest and the least invasive method for this block.[i]
Indications
The best evidence for SPG block is to provide temporary analgesia for cluster headaches, trigeminal neuralgia from the 2nd division, endoscopic sinus/nasal surgery and migraine headaches.
There is less evidence for post dural-puncture headache[i], hemicrania continua and trigeminal neuralgia from other branches of trigeminal nerve. Also has been reported in treatment of intractable hiccups, complex regional pain syndrome, intercostal neuralgia and dysmenorrhea.
Block Technique
The block is easiest performed with the patient in the supine position. A 10cm cotton swab is first soaked in local anesthetic solution. The swab is then inserted into the naris with steady gentle pressure directly posterior towards and past the middle turbinate. Once the back wall is hit, the swab is left in place for 5-10mins. The local anesthetic will anesthetize the mucosa and the SPG which sits directly behind it. Bilateral blocks may need to be performed for bilateral indications. Bilateral blocks can also be performed at the same time. This is block simple enough that some patients can do it at home with some minimal training.
Dosing
2% lidocaine
4% viscous lidocaine
0.5% bupivacaine
Important contraindications
- Patient refusal, local anaesthetic allergy, active local infection and facial or sinus trauma/surgery.
- Relative contraindications are coagulopathy or anticoagulation as severe epistaxis can result. In these settings, risk/benefit consideration must be assessed by the provider.
Side effects
Anesthesia or decreased sensation nose, pharynx and palate. Although not panful, severe lacrimation with insertion of the swab in the nose will likely occur.
Complications
Epistaxis, local hematoma, trauma to surrounding structures including turbinates
Who do I contact if I feel my patient could benefit from a regional anesthesia technique?
When booking OR cases, surgeons can enter requests for regional anesthesia. In inpatients reach out to the Acute Pain Service that covers your campus. Not all providers may be able to perform this block.
Please see the link for the pain team consult service: https://anesthesia.ucsf.edu/divisions/pain-medicine#for-providers--request-consult-or-refer-a-patient
Christopher E. Alexander, Anterpreet Dua, Sphenopalatine Ganglion Block in StatPearls. Copyright © 2022, StatPearls Publishing LLC.
Kent S, Mehaffey G. Transnasal sphenopalatine ganglion block for treatment of postdural puncture headache in obstetric patients. J Clin Anesth. 2016 Nov;34:194-6.