CHOICE OF ANAESTHESIA TECHNIQUE AND EFFECT OF ANAESTHESIA ON SOME MEDICAL DISEASE Flashcards
What is anesthesia
It is a specialty of medicine that deals with the provision of controllable, predictable and reversible methods of pain relief with or without loss of consciousness for operative surgery
List the different anesthesia techniques
• General anaesthesia
• Regional anaesthesia
• Peripheral nerve block
• Local anaesthesia infiltration
• Monitored anaesthesia care
What are the components of GA and methods of administration
Components
Hypnosis
Analgesia
Muscle relaxation
Routes of administration
Intravenous anaesthesia
Inhalational anaesthesia
List the types of regional anesthesia
CENTRAL
Subarachnoid (Spinal)
Epidural
CSE (combined spinal epidural)
Caudal
Saddle block
PERIPHERAL
Axillary block
Bier’s block
Ring block
Wrist block
Ankle block
What do you consider when making a choice for an ideal anesthesia technique?
• Optimal patient safety & satisfaction
• Provide excellent operative condition for surgeon
• Allow rapid recovery
• Avoid postop side effects
What are the considerations that influence choice of anesthesia?
Patient related factors
• Patient’s age
• Comorbid illness
• Fasting status
• Suspected difficult airway
• Patient satisfaction
Surgery related factors
• Type of surgery
• Surgical site
• Need for early awakening and ambulation
• Positioning during surgery
• Anticipated surgery duration
• Surgeon’s preference
Anaesthesia related factors
• Recovery room facilities
• Intraoperative monitoring
• Available anaesthesia equipment
• Previous anaesthetic exposure
• Anaesthetist expertize
List the ASA risk classification
• Class I - Healthy patient
• Class II – Mild systemic disease, with no functional limitation
• Class III – Severe systemic disease, with definite functional limitation
• Class IV - Severe systemic disease, with a constant threat to life
• Class V - Moribund patient, may not survive 24hrs with/without surgery
List some common medical conditions that are considered in anesthesia
Cardiovascular
• Hypertension
• Coronary artery disease
• Heart failure
• Valvular heart disease
• Arrhthymias
Endocrine
• Diabetes mellitus (type I or type II)
• Thyroid disease – Hyperthyroidism/ hypothyroidism
• Phaeochromocytoma
• Addison’s disease
Respiratory
• URTI
• Asthma
• Chronic obstructive airway
Neurological
• Epilepsy
• Myasthenia gravis
Haematological
• Anaemia,
• SCD,
• Haemophilia,
• DVT
Others
• Obesity, sepsis, Burns
• Chronic infections: AIDs, TB, Hepatitis
• Chronic renal failure
• Liver disease
List some of the causes of secondary hypertension
Endocrine
Phaoechromocytoma
Cushing syndrome
Acromegaly
Renal
Renal artery stenosis
Chronic glomerulonephritis
Others
Coarctation of aorta
Pregnancy induced
During anesthesia, what are the things you try to avoid in hypertensive patients.
• Hypotension
• Tachycardia
• Shivering in the postoperative period
NB:- Ketamine is contraindicated for use
During anesthesia, what are the things you try to avoid in MI patients.
• Hypoxia
• Hypercarbia
• Hypo/hypertension
NB:- Control angina with Glyceryl Nitrate, Beta-blockers
During anesthesia, what are the things you try to avoid in valvular heart disease patients.
CVS depression which can cause
• Bradycardia
• Hypotension
During anesthesia, what are the things you try to avoid in asthma patients.
• Thiopentone is contraindicated in GA
• Avoid morphine
• Deep extubation to avoid bronchospasm
• Adequate analgesia to avoid respiratory depression
During anesthesia, what are the things you try to avoid in COPD patients.
- Avoid high FiO2
- Avoid respiratory depressants/hyperventilation
During anesthesia, what are the things you try to avoid in DM patients.
Oral drug control
- Change long acting to short acting hypoglycaemic drug e.g. sulphonylurea
- Omit drug morning of surgery
- For major surgery: Change to soluble insulin using a sliding scale
- Check blood glucose 1-2hrly until fully recovered and returned to oral intake
- Then change to the preoperative regimen
- RA is preferred as much as possible (less swings in blood glucose)
