Definition
The stellate ganglion is a plexus of nerves in the area of the lower neck. It supplies parts of the head, chest and thoracic organs with sympathetic nerve fibers. In the case of a ganglion stellatum blockage, these nerve fibers are specifically eliminated by infiltration of local anesthetic. After a short period of exposure, the affected areas will expand (vasodilatation), sweat secretion will be reduced and Horner’s syndrome will develop: Narrowing of the pupil (miosis), drooping of the upper eyelid (ptosis) and receding of the eye into the orbit (enophthalmos).
Indications for ganglion stellatum blockage
One of the indications of the Ganglion stellatum block is the complex regional pain syndrome (CRPS): After injuries in the arm area, adhesions in the area of the nerve plexus can lead to a misregulation of the sympathetic nervous system. By anesthetizing the nerves, the symptoms can be reduced. A nerve blockage is also possible in trigeminal neuralgia and post-zoster neuralgia.
The sometimes most severe pain can thus be alleviated. Stellate blockade can also be considered in cases of an existing Raynaud’s syndrome. Here one makes use of the vasodilating effect.
Preparation
In addition to a detailed anamnesis and education of the patient, blood coagulation is checked by a blood test. If the patient is taking blood-thinning medication, a possible break should be discussed. Before the procedure, an ECG should be written to detect possible cardiac arrhythmia, which may be a contraindication. No special precautions are necessary on the day of the procedure. After the blockade, the patient should not participate in traffic for 24 hours and should not operate heavy machinery.
Procedure
The ganglion stellatum block is initially performed in a supine position on the awake patient. Throughout the entire procedure, the vital parameters (blood pressure, pulse, oxygen saturation) are continuously measured to immediately counteract a possible drop in circulation. Anaesthesia of the ganglion is always performed on one side only to avoid life-threatening bilateral vocal cord paralysis.
The anesthetist first palpates the carotid artery (Arteria carotis externa). After careful disinfection of the area in the lower part of the neck, the carotid artery is moved slightly outwards. The puncture is performed vertically between the artery and the trachea, with the cannula being advanced to the transverse process of the 6th cervical vertebra.
The needle is either inserted blindly, in which case the attending physician must be able to palpate and identify the surrounding structures. In patients with a larger soft tissue mantle, the puncture can also be controlled by ultrasound. If the needle is placed correctly, after aspiration, 5-10ml of local anesthetic (bupivacaine, mepivacaine) is injected.
After removing the needle, the patient is immediately put on the needle to cause the local anesthetic to subside. The local anesthetic is now distributed in the tissue of the lower neck and anesthetizes the entire nerve plexus. If the sympathetic nerve fibers are successfully blocked, the skin in the affected area is overheated, dry and well supplied with blood.
Afterwards, the patient’s circulation and neurological status continues to be closely monitored. In order to achieve the desired effect, a series of 5-10 blockades is usually performed at intervals of 1-3 days. The therapy should be carried out in a pain-free period.
