A Posterior Fossa Decompression is done to relieve the constriction and create more space at the base of the brain.
The procedure involves a cut being made into the tissues at the back of the head and the neck bones covering the base of the brain.
A small section of bone is removed from the base of the skull (occipital bone) and at times from the upper back(C1 posterior arch). There is a tight band of tissue or scar tissue around the base of the brain which constricts the lining of the brain.
For this reason, the lining of the brain is opened to allow further relief. Through a separate cut, a tissue graft is taken from the patient’s thigh and placed in the opening of the brain. It is stitched into position to widen the opening and create more space for the base of the brain.
The bone will be left out and the cut is closed with sutures or clips.
This procedure is done under general anaesthesia. You are positioned in a face down position with the head held rigidly in a three pin brace and a special operating table.
Risks of Procedure
There are some risks/complications with this procedure.
Common risks include:
- Fluid leakage from around the brain can occur after the operation. This may require further surgery.
- Infection. This may need antibiotics and further treatment.
- Bleeding. A return to the operating room for further surgery may be required if bleeding occurs. Bleeding is more common if you have been taking blood thinning drugs such as Warfarin, Aspirin, Clopidogrel (Plavix or Iscover) or Dipyridamole (Persantin or Asasantin).
Uncommon risks include:
- A heart attack because of the strain on the heart.
- Stroke or stroke like complications can occur which can cause weakness in the face, arms and legs. This could be temporary or permanent.
- The problem may not be cured by this surgery. This may require further treatment.
- Small areas of the lung may collapse, increasing the risk of chest infection. This may need antibiotics and physiotherapy.
- Increase risk in obese people of wound infection, chest infection, heart and lung complications, and thrombosis.
- Clots in the leg (deep vein thrombosis or DVT) with pain and swelling. Rarely part of this clot may break off and go into the lungs.
- After your surgery you will remain in the recovery area until you are stable and comfortable then you will be transferred to the high dependency care unit for approximately 24 hours after your operation.
- Nursing staff will monitor your vital signs hourly. They will also monitor your wound, intravenous drip, your oral intake and urinary output. In most cases you will have a urinary catheter insitu and this will be removed 1 -2 days after surgery. You are allowed to commence food and fluids as tolerated if you do not feel nauseous and if your swallow is good. Please advise staff if you are experiencing any increased difficulty with your swallowing.
- As you will need to remain in bed, your nurse will give you a hot towel wash on returning to the ward.
- You will have oxygen delivered through nasal tubing that needs to remain in place for the first 24 hours.
- Nursing staff will ask you regularly if you have any pain and will use a pain score system to assess your level of pain.
You will be asked to rate your pain on a scale of O to 10.
O = no pain
10 = worst possible pain
Based on your answer, nursing staff will arrange appropriate pain relief medication to be given to you.
- The type of pain relief available includes tablets, injections, hot packs and less often PCA's (patient controlled analgesia) which allows you to administer your own pain relief via your drip. Note: PCA's are not routinely used and are only used if ordered by the anaesthetist.
- Please keep in mind that you may still feel some pain despite having pain relief, therefore, please inform your nurse if the medication does not reduce your pain or if your pain level increases. This may mean that your medication dose needs adjusting.
- Please advise your nurse when the pain first starts. Do not wait until the pain is bad or leave it for long periods before you take the medication as this means it will take longer to control the pain.
- If you are feeling nauseated, please let your nurse know so they can administer medications to control this and make you more comfortable
- You will be required to rest in bed initially post-operatively with head of the bed elevated to 300 . As the anaesthetic wears off you will be allowed to mobilise with assistance. Please do not attempt to mobilise without assistance.
- Pressure area care will be attended by your nurses. This involves an assisted roll in bed which will help to relieve pressure, allowing skin care to be attended.
I usually review you while you are in the recovery room and then give your designated, next of kin, a call to let them know how the surgery went and how you are after surgery. Occasionally this will not be possible due to time restraints.
I will visit you today to discuss your operation and see how you are progressing.
Following the visit
- Your wound drain will be usually removed after review by me(if present).
- Your intravenous antibiotics and intravenous fluids will be ceased.
- Your wound will be inspected and monitored regularly. In particular, clear fluid leakage (Brain fluid) from the wound will be looked for.
- You will be commenced on a bowel regime to prevent and help avoid constipation.
- Your level of pain will be assessed to ensure you are on the appropriate medication.
- I strongly recommend you take pain relief regularly (i.e. every 4 hours) for the first 48 hours to ensure your optimal comfort and recovery. Tablets are the most frequently used type of pain management, usually given 4-6 hourly and are a step forward in your recovery towards discharge home.
- The frequency of your vital sign monitoring will be reduced.
- Your nurse will assist you with a wash as instructed. The surgical site will be kept dry and covered.
- You will continue to wear your anti-embolic stockings throughout your hospital stay. Your physiotherapist will also visit you in the morning to assess you and assist you to mobilise as tolerated.
- We advise you to change positions regularly between lying, sitting, standing and walking
- You may sit out of bed as tolerated depending on your level of pain.
Day 2 to discharge
- We encourage you to gradually increase your activity levels each day with the aim of increasing your independence and mobility in preparation for your discharge home.
- I will visit you daily to ensure you are progressing well and discharge planning will continue post-operatively.
- If you have any questions or concerns regarding your discharge arrangements you may contact the Clinical Nurse manager, team leader or discharge planner in the ward at any time to discuss these. Your nurse can make this contact for you.
- Your physiotherapist will also continue to visit you daily to see how you are progressing and review your exercise and mobility regime.