Anaesthesia Flashcards
List 4 types of anaesthesia
- General Anaesthetic
- Local Anaesthetic
- Regional Anaesthetic (Spinal Block/ Subarachnoid Block)
- Epidural (Extradural Block)
Define general anaesthesia
A state of controlled unconsciousness
What are the indications for general anaesthesia?
- Long operations
- Painful operations
- Patient unable to tolerate procedure while awake
- Need for patient to be paralysed during the procedure
What are the contraindications for general anaesthesia?
- Sustained hypertension
- Severe anaemia
- Advanced lung disease
- Obesity
- Previous anaphylaxis to general anaesthesia
What are the fasting requirements with general anaesthesia?
Fast from food for 6 hours
Fast from water for 2 hours
What are the key risks associated with general anaesthetic?
- Anaphylaxis
- Malignant hyperthermia
- Waking during the procedure
- Death (1 in 100,000)
Name two methods for providing local anaesthetic
- Topical anaesthesia
- Infiltration
Define local anaesthesia
Anaesthesia that causes an absence of sensation in a specific part of the body but generally for the aim of inducing local analgesia.
What are the common indications for local anaesthesia?
- Mouth / dental treatment
- Nebulised to prevent cough / allow passage of a scope
- Skin surface numbing
- Post operative analgesia
ESSENTIALLY ANY PROCEDURE THAT REQUIRES ANALGESIA BUT NOT FULL SEDATION OR PARALYSIS.
What are the fasting requirements for local anaesthesia?
No fasting required- patient can eat and drink as normal unless contraindicated for other reasons
What are the contraindications associated with local anaesthesia?
- History of allergy or anaphylaxis to the drug of choice
- Acute or supportive infection present where the LA is to be introduced
- Avoid LA containing vasoconstrictors in patients with cardiovascular disease
- Take care with choice of drug in renal and hepatic impairment
By what other names are spinal anaesthetic known by?
- Subarachnoid block
- Intradural block
- Regional block
- Intrathecal block
Define spinal anaesthesia
A special type of local anaesthetic that creates anaesthesia throughout the distribution of the spinal nerve at the level of the block. Can be used alone or in combination with sedation.
What are the indications for spinal anaesthesia?
Procedures where general anaesthetic poses to great a risk to the patient but the surgery is necessary and it is important for a complete block.
Give examples of surgical procedures where spinal anaesthesia may be used
- Orthopaedic surgery
- Lower limb vascular surgery
- EVAR
- Hernia repair (inguinal or epigastric)
- TURP
- Abdominal / vaginal hysterectomy
- C Section
What are the contraindications associated with spinal anaesthesia?
- Local infection at the puncture site
- Bleeding disorders ( increased risk of spinal haematoma)
- Space occupying lesion of the brain
- Anatomical disorder of the spine
- Hypovolaemia
What are the main side effects associated with spinal anaesthesia?
- Hypotension ( spinal shock) due to sympathetic blockade
- Post dural headache
- Spinal heamatoma
- Cauda equina injury
- Epidural abscess
What are the fasting requirements for spinal anaesthesia?
Fast from food for 6 hours
Fast from water for 2 hours
How is an epidural different from a spinal block?
With an epidural the administered drug does not infiltrate the CSF. Epidural is used to achieve segmental analgesia or anaesthesia.
Epidural can be performed anywhere on the spinal canal not just the lumbar region (as for spinal block).
What are the indications for epidural?
Analgesia
- Childbirth pain
- Adjunt for post op pain management
- Chronic back pain
- Other chronic pain or pain associated with terminal illness
What are the main side effects of an epidural?
- Does not selectively block nociceptors
- Urinary incontinence
- Paralysis of intercostal or thoracic muscles at chest level
- Accidental dural puncture and subsequent headache
What are the fasting requirements for an epidural?
Fast from food for 6 hours
Fast from water for 2 hours
