Problem 8: Peri-Operative Anaesthesia

Question 1

Explain the difference between spinal and general anesthesia?

Answer 1

Spinal anesthesia (or spinal block) is a form of regional anesthesia involving injection of local anesthetic into the subarachnoid space. 
Risks and complications include; hypotension, post-dural-puncture headache, insertion height too high, cardiac arrest in underlying medical conditions, spinal canal hematoma, epidural abscess. Spinal anaesthetics are typically limited to procedures involving most structures below the upper abdomen. Epidural is local anesthetic via catheter into epidural space. Epidural is delivered outside of the dura (whereas spinal is direct to CSF of spine)

General anesthetic is a state of controlled unconsciousness; liquid of gas in the inductive phase, maintained during operation. Recovery is slow and gradual wake up. Side effects are feeling sick and vomiting, shivering and feeling cold, confusion and memory loss, bladder problems, dizziness, bruising and soreness, sore throat, damage to mouth or teeth. Complications and risk of serious allergic reaction, waking up during the operation, death.

Question 2

The anaesthetic review states that the patient is for “spinal with sedation”. Describe what this is, when it might be used. Is this the same as a general anaesthetic? Describe the impact the use of spinal anaesthetic can have on patients anticoagulation management?

Answer 2

Spinal with sedation:
spinal anesthetic (so the patient remains conscious) with sedation which involves using small amounts of anaesthetic drugs to produce a ‘sleep-like’ state. It makes
you physically and mentally relaxed, but not unconscious.
Many people having a local or regional anaesthetic do not want to be awake for surgery. They
choose to have sedation as well.
If you have sedation, you may remember little or nothing about the operation or procedure.
However, sedation does not guarantee that you will have no memory of the operation. Only a
general anaesthetic can do that.

For patients taking antithrombotic medication, concerns exist about the risk of perineural bleeding complications or neurological damage from compressive vertebral canal haematoma (VCH). When LMWHs are administered in therapeutic doses for anticoagulation (typical doses; enoxaparin 40–100 mg twice daily, dalteparin 5000–10 000 units twice daily, depending on body weight), an interval of at least 24 h should elapse before regional anaesthesia.

Question 3

Provide examples of analgesia that Anna may require.

Answer 3

Paracetamol: 6 hourly (as IV or oral)
Opioid: weak opioids are second line in post-operative pain if paracetamol monotherapy is not sufficient. Sometimes an IM injection of codeine is given to patients towards the end of an operation (sometimes makes histamine induced red lump on patients thigh). Codeine, tramadol, dihydrocodeine are weak opioids.
Nerve block

Whenever prescribing opioids for regular administration, you should consider prescribing a laxative too. Stimulant laxative such as senna is a reasonable choice.
NSAIDs are not recommended