Regional anesthesia involves blocking sensation in specific parts of the body while the patient remains awake or sedated. It is classified into several main categories based on the anatomical target and technique.
1. Neuraxial Anesthesia
Spinal Anesthesia
Injection Site: Into the subarachnoid space (cerebrospinal fluid)
Use: Cesarean sections, pelvic and lower limb surgeries
Onset: Rapid
Duration: Single dose, limited duration
Epidural Anesthesia
Injection Site: Epidural space, outside the dura mater
Use: Labor analgesia, abdominal or thoracic surgeries
Onset: Slower than spinal
Duration: Can be continuous with a catheter
Caudal Anesthesia
Injection Site: Via the sacral hiatus into the epidural space
Use: Pediatric surgeries, anorectal procedures
2. Peripheral Nerve Blocks
Upper Extremity Blocks
Interscalene Block: For shoulder and upper arm
Supraclavicular Block: For arm and forearm
Infraclavicular/Axillary Blocks: For elbow, forearm, hand
Lower Extremity Blocks
Femoral Nerve Block: Anterior thigh and knee
Sciatic Nerve Block: Posterior thigh, lower leg, and foot
Adductor Canal Block: Knee surgery, spares quadriceps function
3. Truncal Blocks
TAP Block (Transversus Abdominis Plane)
Use: Analgesia for abdominal wall incisions
Technique: Local anesthetic between internal oblique and transversus abdominis
Rectus Sheath Block
Use: Midline abdominal surgeries
PECS Block (Pectoral Nerve Block)
Use: Breast and chest wall surgeries
ESP Block (Erector Spinae Plane Block)
Use: Thoracic, abdominal, and spinal surgeries
Injection Site: Deep to erector spinae muscle
4. Imaging and Guidance
Ultrasound Guidance: Enhances safety and accuracy by visualizing nerves and anatomical structures
Nerve Stimulation: Sometimes used alongside ultrasound to confirm correct nerve localization