Combined Spinal Epidural procedure
- Patient has to be consented for epidural in addition to the spinal.
- Epidural involves using a larger needle with greater likelyhood of PDPH (Post Dural Puncture Headache), should inadvertent puncture occur.
Preparation CSE can be done either in the labour ward or in the anasthetic room of in the operating room. The procedure is done under strict asepsis after establishing a venous access and with intravenous fluids and emergency drugs (metaraminol, phenylephrine, etc.) at hand. The patient is asked to sit erect with the back fully exposed.
- Locate the interspinous space, inject local anaesthetic (lignocaine 1%), and go to scrub.
- Use the CSE kit containing tuohy 16G needle, 27G Whitacre needle, Loss of Resistance syringe, Filter, Epidural catheter, conector, few syringes and needles.
- Keep a syringe ready loaded with Bupivacaine 0.5% heavy 2 to 2.5ml with 0.3mg of Diamorphine.
- Keep the loss of resistance syringe loaded with 0.9% saline and keep Diamorphine syringe out of sight
- Prepare the back of the patient by spraying chlorhexidine spray and cover the clean area with a ready made paper towel with adhesive fix.
- Positioning the patient is the most important single step which makes a difference between success and failure. Ensure that the patient stays in the correct position while locating the space.
- Once the tip of the epidural needle enters the interspinous ligament, the needle is held in place and we get a springy feeling. A saline filled loss of resistance syringe is attached tightly to the hub of the needle. The epidural needle and syringe are advanced together. A constant pressure is applied on the syringe.
- Once the tip of the epidural needle enters the epidural space, the anaesthetist feels sudden loss of resistance. Inject a few more mls of Normal saline to confirm the position in the epidural space. Now disconnect the syringe from the needle. A few saline drops may flow out and this might sometimes create a panic in the less experienced anaesthetist as dural tap. If in doubt you can use a litmus paper or Glucostix to rule out the CSF.
The CSE kit comes with a custom made spinal needle (27 Gauge Whitacre).Now pass the spinal needle through the epidural needle. As the spinal needle used in CSE is very narrow, apply suction with a 5ml syringe to detect the entry into the Subarachnoid space. Alternatively we can allow CSF to flow on its own, which however will be very slow due to the very narrow gauge of the spinal needle. Inject 2.2 to 2.8 ml of Bupivacaine 0.5% (heavy) with Diamorphine 300micrograms. Inject slowly and aspirate repeatedly to ensure that the entire volume of the drug is deposited in the CSF. Next step is to take out the Spinal needle and insert epidural catheter.Inject a few ml of saline to confirm that the epidural needle is still in the right place and has not moved into CSF or come out of the epidural space. It is a good practice not to inject too much of saline into the epidural at this stage. Too much Saline in the epidural space may increase the height of the spinal block and result in too high a block. Leave 3-5 ml of epidural catheter in the epidural space (If the depth of the epidural space is 5cms (8-10cms at skin), and secure the catheter in place with adhesive tape. It is a good practice to cover the catheter entry point by a transparent tape as it will enable us to detect catheter migration and bleeding from the site. If there is a bleeding point apply firm pressure for a few minutes till the bleeding stops. If the bleeding still continues apply a firm pressure bandage over the puncture site. It is important to keep in mind that if the patient is kept in the sitting position for a long time the block may not reach the required height. NB: 1.Once the spinal drugs are injected patient feels warm and tingly in the legs. The patient has to be physically held as patient may feel fainting sensation. Ask the ODP to hold the patient physically till the patient is placed in the supine position.
It makes the best use of Spinal (quick onset and dense block), and Epidural (prolong the regional block if surgery goes on longer than anticipated, and increase the height of block as needed, post op analgesia).
Takes longer to establish and technically more demanding.
Points to remember
- Take consent for CSE and explain about the benefits of epidural and also the increased risk of PDPH if Epidural needle enters the CSF.
- Positioning of the patient is extremely important. If the patient is not positioned correctly we will never get it right.
- There is no justification in persevering for hours till you succeed. The back need not be used for target practice. If you don't get it in two attempts, make sure that the position is right and you are in the right place and the needle is at the right angle.
- Ask an anaesthetic colleague to help if you are not successful. Ego should not come in the way of patient care.
- If you are alone go for spinal in the usual way and explain to the patient the change in your technique.
- Patient and her partner should be taken into confidence through out the procedure and repeatedly stress about the importance of maintaining the correct posture.
- It is good to let the patient know that the success of the procedure depends largely upon her understanding and complete cooperation.