anaesthetics Flashcards
Isolated fever in well patient in first 24 hours following surgery
physiological reaction to operation
skin commensals take 48 h
Pseudocholinesterase deficiency
abnormality in the production of plasma cholinesterases. This leads to an increased duration of action of muscle relaxants used in anaesthesia, such as suxamethonium.
Propofol
Rapid onset of anaesthesia
Pain on IV injection
Rapidly metabolised with little accumulation of metabolites
Proven anti emetic properties
Moderate myocardial depression
Widely used especially for maintaining sedation on ITU, total IV anaesthesia and for daycase surgery
Sodium thiopentone
Extremely rapid onset of action making it the agent of choice for rapid sequence of induction Marked myocardial depression may occur Metabolites build up quickly Unsuitable for maintenance infusion Little analgesic effects
Ketamine
May be used for induction of anaesthesia
Has moderate to strong analgesic properties
Produces little myocardial depression making it a suitable agent for anaesthesia in those who are haemodynamically unstable
May induce state of dissociative anaesthesia resulting in nightmares
Etomidate
Has favorable cardiac safety profile with very little haemodynamic instability
No analgesic properties
Unsuitable for maintaining sedation as prolonged (and even brief) use may result in adrenal suppression
Post operative vomiting is common
ASA 1,2,3,4,5,6
healthy, mild systemic disease/ smoker drinker, severe systemic disease (bmi over 40), disease constant threat to life, will die without op, dead but organ donor
Depolarizing NMJ blocker
Binds to nicotinic acetylcholine receptors resulting in persistent depolarization of the motor end plate
Succinylcholine (also known as suxamethonium)
s/e Malignant hyperthermia
Hyperkalaemia (normally transient)
The muscle relaxant of choice for rapid sequence induction for intubation
May cause fasciculations
Suxamethonium is contraindicated for patients with penetrating eye injuries or acute narrow angle glaucoma, as suxamethonium increases intra-ocular pressure
also contraindicated in burns due to hyperkalaemia
Non-depolarizing nmj blocker
Competitive antagonist of nicotinic acetylcholine receptors
Tubcurarine, atracurium, vecuronium, pancuronium
s/e Hypotension
reversal Acetylcholinesterase inhibitors (e.g. neostigmine)
vte prophylaxis for
elective hip replacement
elective knee replacement
hip fracture
28days
14 days
until pt no longer has reduced mobility
perforated appendicitis with pelvic and sub phrenic abscesses. He has now deteriorated further and developed deranged liver function tests.
marked intra-abdominal sepsis may well produce coagulopathy and the risk of portal vein thrombosis.
The COC should be stopped:
Four weeks before any major surgery (which includes operations lasting more than 30 minute), all surgery to the legs, or surgery that involves prolonged immobilization of a lower limb.
If emergency surgery or immobilization (such as for a leg fracture) is necessary.
Ix for anastamotic leak
ct abdo
Complications of perioperative hypothermia
Coagulopathy: hypothermia reduces blood’s ability to clot, causing increased intra-operative blood loss.
Prolonged recovery from anaesthesia: small decreases in body temperature can cause drastic prolongation of anaesthetic drugs, both neuromuscular blocking agents (NMBAs), propofol and inhalational agents.
Reduced wound healing: hypothermia leads to local vasoconstriction which reduces perfusion to the skin, this reduces the necessary immune moderators available at the site to promote healing.6
Infection: a combination of poorer incisional site healing and also reduced number of immune cells able to access the skin leads to a significantly increased risk of infection.
Shivering: whilst shivering appears benign in the healthy population, it can cause a significant increase in metabolic rate which can in certain patient groups even result in myocardial ischaemia.
G+S/xmatch before op?
Unlikely Group and save Hysterectomy (simple), appendicectomy, thyroidectomy, elective lower segment caesarean section, laparoscopic cholecystectomy
Likely Cross-match 2 units Salpingectomy for ruptured ectopic pregnancy, total hip replacement
Definite Cross-match 4-6 units Total gastrectomy, oophorectomy, oesophagectomy
Elective AAA repair, cystectomy, hepatectomy
