A prospective observational study to determine the effectiveness of USG and PNS guided combination of T12 paravertebral,lumbar plexus and sacral plexus blocks in high risk patients undergoing hip surgeries

Regional anesthesia is the most commonly used method of anesthesia for lower limb surgeries and the most common mode of regional anesthesia used is neuraxial anesthesia (spinal/epidural).

The benefits of using regional anesthesia in hip fracture surgeries as compared to the use of general anesthesia are significant reduction in the number of complications like the airway instrumentation and manipulation, venous thromboembolism, respiratory complications ,also has advantage of early resumption of oral intake postoperatively. Neuraxial anesthesia has several disadvantages like perioperative hemodynamic instability, urinary retention, epidural hematoma etc which can lead to undesirable events like myocardial infarction, stroke and CNS infection in high-risk surgical patients and patients on anticoagulant or antiplatelet medications which possess higher risk of postoperative morbidity and mortality.

Peripheral nerve blocks which block one or more Peripheral nerves that supply the surgical field in the operative limb are an effective method for lower limb surgeries.Newer techniques that is ultrasound-guided nerve blocks with nerve stimulator increase the success rate and reduce risks such as nerve injuries, hematomas and renal puncture.They also provide postoperative pain relief with improved patient satisfaction, stable hemodynamics, early ambulation thereby reducing the length of hospital stay.

The upper dermatome level of sensory block to T10 is recommended for hip surgery with spinal anesthesia. Recent studies show a dermatome level up to T12 may satisfy the requirement of surgical anesthesia for hip replacement. The nerves innervating the hip joints arise from the ventral rami of the spinal nerve roots of the lower part of the lumbar plexus (L2-4) and the upper part of the sacral plexus (L4-S1). The lateral femoral cutaneous nerve from the lumbar plexus (L2-L3), lateral cutaneous branch of iliohypogastric nerve (T12 and L1) and subcostal nerve (T12 thoracic nerve) innervate the area of the superior lateral gluteal region and the proximal lateral thigh that are involved in skin incision of posterolateral approach to hip joint .

Lumbar plexus block results in blockade of the femoral nerve, lateral femoral cutaneous nerve and the obturator nerve while the sacral plexus block results in blockade of the sciatic nerve, posterior cutaneous nerve of thigh, superior and inferior gluteal nerves, pudendal nerve, pelvic splanchnic nerve, inferior hypo- gastric plexus and the terminal portion of sympathetic trunk.

lumbar plexus and sacral plexus block do not provide enough sensory block in L1 and T12 dermatome which is required for consistent surgical anesthesia for hip surgery. To overcome this supplemental dosage of propofol and opioids, infiltration at incision and iliac crest point block are required. However, these techniques are not reliable, and conversion to general anesthesia is often required.

An ultrasound guided T12 Paravertebral block (PVB) provide sensory block of subcostal nerve and iliohypogastric nerve, it also blocks the superior gluteal cutaneous nerve derived from posterior branch of L1 and L2 spinal nerves through a paravertebral space spread.

This T12 PVB is safe, effective and simple, and will produce sensory blockade covering the surgical incision to the level above the great trochanter on the superior lateral gluteal region.

So far no study has done at our institution to determine the effectiveness of USG and PNS guided combination of these 3 blocks.So I would like to carry out this observational study.