Estimated reading time: 5 minutes
When any resident enters modern anesthesia, local approaches have transformed how we manage pain before, during, and after surgery. Instead of depending upon systemic medications, these unified techniques allow all the anesthesiologists to target all the specific nerves, which include reducing pain and enhancing recovery. Let’s walk through some essential nerve blocks, their mechanisms, and clinical applications in a very clear form, as it will be easy to follow.
The Erector Spinae Plane Block: A Rising Star in Thoracic Surgery
Have you ever imagined a patient has been undergoing thoracic surgery for a lobectomy? Basically, the anesthesiologists depend upon the thoracic epidurals or paravertebral nerve blocks, which help to control pain. While epidurals are familiar and widely practiced, they often deal with challenges like they have to suffer from technical difficulty, risks of hypotension, and sometimes they have limited postoperative use.
This is where the Erector Spinae Plane (ESP) block shines. That is usually performed under ultrasound guidance, as it is kind of simple and safe, which helps to make it increasingly popular.
Anatomy in Action
The erector spinae group consists of three muscles, spinalis, longissimus, and iliocostalis, running parallel to the spine, anchored over the transverse processes of the vertebrae. From superficial to deep, these muscles are covered by the trapezius and rhomboid, before resting directly over the transverse process.
During an ESP block:
- The ultrasound probe is placed longitudinally, just parallel to the spine.
- The three muscle layers (trapezius, rhomboid, erector spinae) are visualized clearly.
- A needle is advanced until it touches the transverse process.
- About 20 ml of local anesthetic, like bupivacaine (0.125–0.25%) or ropivacaine (0.2%), is deposited beneath the erector spinae muscle.
As the drug spreads, it lifts the muscle off the transverse process, creating a visible “plane.” This diffusion blocks the dorsal rami, providing pain relief for 2–3 dermatomal levels. With some spread, even ventral rami and intercostal nerves can be affected, extending analgesia to the anterolateral chest wall.
Clinical Use
The ESP block is excellent for:
- Thoracic surgeries
- Spine surgeries
- Rib fractures
- Some breast surgeries (though paravertebral blocks remain superior for mastectomies)
Its mechanism? Diffusion of the anesthetic into the paravertebral and epidural spaces, covering both dorsal and ventral rami. Simple, elegant, and effective.
The Greater Occipital Nerve Block: Relieving Headaches
Headaches can be tiring, especially when it is linked to subcortical neuralgia or a person who has
migraine syndromes. So now, here is the Greater Occipital Nerve Block (GONB) provides targeted relief.
Finding the Right Spot
It is necessary to find the right spot, so the greater occipital nerve runs close to the occipital artery, which makes the landmarks essential:
- Occipital protuberance, there is a prominent bump at the back of the head)
- The mastoid process is basically behind the ear bone.
Draw a line between the two, and at about one-third from the occipital protuberance, you’ll find the injection point. Alternatively, you can palpate the occipital artery and inject just medial to it.
Another quick trick? Go 2 cm inferior and 2 cm lateral to the occipital protuberance.
Only a small volume, 2–3 ml of local anesthetic (often 0.25% bupivacaine with dexamethasone), is required.
Indications
- Migraine
- Cluster headaches
- Cervicogenic headaches
- Post-dural puncture headaches
By blocking the greater occipital nerve, patients often experience remarkable relief, making this a simple but powerful tool.
Trigeminal Ganglion Radiofrequency Ablation: Pain Relief with Risks
For patients with long-standing trigeminal neuralgia unresponsive to medications, radiofrequency ablation of the trigeminal ganglion is considered. But, like all procedures, it carries potential complications.
The trigeminal ganglion gives rise to three divisions:
- V1 (ophthalmic) – sensory to forehead, scalp, upper eyelid, cornea, and tip of the nose
- V2 (maxillary) – sensory to cheeks, upper lip, and lower eyelid
- V3 (mandibular) – sensory to the jaw + motor to muscles of mastication
If V1 is affected, complications include corneal anesthesia, which risks eye injury due to loss of protective sensation. Patients may also experience dysesthesia—an unpleasant burning or tingling sensation.
Thus, while effective for pain, this procedure demands precision and careful patient selection.
Interscalene Brachial Plexus Block: A Double-Edged Sword
Moving from the head and spine to the shoulder—consider a patient scheduled for elective orthopedic surgery. The interscalene block, performed under ultrasound, is a trusted method for shoulder analgesia.
Anatomy Snapshot
- The brachial plexus roots (C5, C6, C7) sit in the interscalene groove between the anterior scalene (medial) and middle scalene (lateral).
- A needle is introduced laterally to medially, and local anesthetic is deposited in the groove.
The Catch
Right above the anterior scalene lies the phrenic nerve, which powers the diaphragm. There the large drug volumes (e.g, 15 ml), local anesthetics can spread and block the phrenic nerve, which leads to hemidiaphragmatic paralysis.
You know what, the most healthy patients tolerate this issue well, but those who have compromised lung function may develop respiratory distress.
This is why modern practice favors:
- Lower drug volumes (~10 ml)
- Precise ultrasound guidance
- A lateral-to-medial approach to minimize phrenic involvement
Conclusion
Regional anesthesia is all about exactness, safety, and patient comfort. For patients ESP block has now become the simplest yet powerful option for thoracic and spine surgeries. The GONB offers very quick relief for headaches, while trigeminal ganglion procedures target stubborn neuralgia with some sensory risks. The interscalene block remains excellent for shoulder surgeries but requires care to avoid phrenic nerve paralysis.
In essence, each block has its place; when chosen wisely, these techniques not only control pain but also speed recovery and improve overall surgical outcomes.
