CELIAC PLEXUS BLOCK

PROCEDURE

Will be dealt under following headings:

1) History.2) Neurolytic Agents.3) Methods.4) Patient Preparation.5) Approaches.6) Procedure.7) Complications.

History

Methods• Conceptually speaking, CPB can be

accomplished via two methods:1. Retrocrural2. Antecrural

Patient Preparation

Positioning

1. Patient is positioned prone and a pillow placed under the abdomen and hips to decrease lumbar lordosis (Posterior approach).

2. One needle technique can be carried out in right lateral decubitus position with a pillow placed under the flank.

3. Patient can be placed in supine position in Anterior approach.

Preoperative Medication1. Oral anticoagulants must be stopped and

coagulation status optimised.2. Anti-hypertensives are continued although

they may add to hypotensive effects of CPB.3. Hydration and electrolyte balance should

be corrected, particularly in debilitated and elderly patients.

4. Opioids should be continued.

Monitoring

Monitoring is essential during the performance of block in prone position and include: Pulse oximetry, NIBP, and EKG.

Approaches• Approaches can be:1. Posterior (retrocrural) approach2. Transcrural approach3. Anterior approach4. Transaortic approach5. Transintervertebral disc approach6. Thoracoscopic dennervation7. Intraoperative injection

The Method may be:8. Blind 9. Fluoroscopy guided10.CT guided11.USG guided

Retrocrural Approach• Patient is prone.• Surface Marking:

1. The block is performed with a 15-cm, 20-22 G needle.2. The left sided needle is placed first because the aorta

is a helpful landmark to assist with correct placement.3. After sterile preparation, infiltrate the skin,

subcutaneous, and muscle layers with 0.5 % lidocaine along the anticipated course of the block needles.

4. Use the previously drawn line between the needle entry site and T12 to guide the needle direction, and advance it at a 45� angle from the horizontal plane toward the body of T12 or L1 (see diagram below).

5. Bony contact should be made at an average depth of 7-9 cm.

6. Observe the distance that the vertebral body is contacted.

7. Withdraw the needle and reinsert it at an increased angle of 5�-10o� to allow the tip to slide off the vertebral body anterolaterally.

8. The needle is advanced approximately 1.5-2 cm past the original insertion depth.

9. Stop advancing the needle at the first sign of increased tissue resistance, because this probably represents the aorta.

10. Aortic pulsations can be felt as they are transmitted along the needle when it is correctly placed.

11. Repeat the procedure on the right side. The aorta is not present on the right The needle is advanced approximately 1 cm deeper on the

right12. Observe the needles for leakage of blood, urine, or CSF.

13. After careful aspiration, inject 5-10 ml of a diagnostic test dose containing 0.25 % bupivacaine with 1:200,000 epinephrine through each needle.

14. If the patient receives good pain relief from the test dose above then a neurolytic block can be performed by injecting 10-20 ml of 50-100% alcohol slowly through each needle.

15. Flush needles with anesthetic or air then remove the needles.

Transcrural approach• With this technique, the needle pierces the crus of

diaphragm to finish anterior and caudad to the diaphragm in the same plane as of aorta, anterior to it.

• Differences from retrocrural approach:1.  Radiographic assistance is useful.2. Needle is advanced 1-2 cm further compared to the

classical Retrocrural approach. 3. A loss of resistance is perceived once the crus of the

diaphragm is passed.

Transcrural – One Needle Method

• The needle is inserted 4- 6cm from the midline on the right at the level of lower edge of L1 vertebral body and after passing it, advanced to the antero- lateral wall of the aorta with tip slightly adjacent (pre-aortic).

• Pt. may be positioned lateral.

Anterior approach• Conventional posterior approach for celiac plexus

block sometimes cannot be used in patients, whose anatomical relationship of the retroperitoneal organs is distorted by cancer growth or by a previously performed operation.

• Disadvantage is due to passage of the needle through the liver, stomach, small/large bowel and pancreas to reach the coeliac ganglia and include, risk of infection, haemorrhage and fistula formation.

• Advantages is complication rate (a lower risk of neurologic injury related to the neurolytic solution spread to somatic nerve roots) and reduced patient discomfort (prolonged prone positioning avoided).

• It requires placement of needle anterior to the diaphragmatic crus (at or between the coeliac or superior mesenteric arteries).

• Pt. Supine.• Done under fluoroscopy/CT

guidance.• LA infiltration in midline

epigastrium deep down till the peritoneum.

• A 20G, 15cm needle is introduced at the midline of epigastrium and is advanced perpendicular to the skin until the needle tip touches the body of L1 vertebra.

• The needle is pulled back 1-2cm, negative aspiration ascertained and contrast injection under fluoroscopic guidance confirms correct needle - tip placement.

• This is followed by 40ml of injectate

Transaortic approach1. The posterior transaortic approach uses a single 22G 13 cm

needle that is passed through the posterior and anterior walls of the aorta via a left posterior paramedian approach.

2. In periaortic area, transmitted pulsations are felt.3. Increased resistance as needle passes through aortic wall.4. Appearance of blood confirms intraortic placement.5. Further advanced till aspiration ob blood ceases.6. Only 25 ml of injectate is required.7. Higher risk of retroperitoneal hemorrhage.

Complications• Arterial hypotension (38%), low pain (96%), and diarrhoea

(44%) are the most common complication.

• Hypotension is of orthostatic nature which is primarily due to loss of sympathetic tone and consequent splanchnic vasodilatation. Fluid, vasopressors and abdominal binders suffice.

• Pain initially (upto 30 min) burning type in epigastric, chest or mid-back immediately after administration of neurolytic solution.

Later on a dull aching pain takes over and remain upto 48 hours.

Responds to intravenous opioids or oral analgesics.

• Self limiting diarrhoea due to uninhibited action of the parasympathetic system may occur.

Radiographic guidance• The use of radiodiagnostic aid is essential to determine and

confirm correct needle placement and the contrast media spread.

• Fluoroscopy: Only AP and Lateral views are required. Details beyond scope.

• CT-scan guided technique allows precise placement of the needles, reduces risk of organ injury and is especially preferred when normal anatomy is distorted by malignancy.

Disadvantages includes:1. Confirms only the needle position and continuous guidance

during the procedure is not possible2. Time consuming and expensive, 3. Exposes patient and physician to more radiation4. Claustrophobic for the patient5. Needs the patient to remain immobile for longer period of time.

A Final Word• Provided that usual precautionary

measures are exercised and observed, experienced physicians can safely administer CPB basing on topographic guidance alone.

• Following a large series of study, it was not clear that use of fluoroscopy actually reduces incidence of complications.

• It does show, however, that CT-scan may add to the margin of safety relative to fluoroscopy but at the same time small number of complications have been also reported during its use.

Interestingly,..• Interestingly, patients show up with

detectable alcohol odour on breath and blood alcohol concentration following alcohol neurolysis.

• This stays for several hours after procedure but are insufficient to produce systemic effects

Thank You