Haemostasis Flashcards
Physiologic haemostasis occurs in three interrelated phases: initiation, amplification, and propagation.
T
Regarding physiologic haemostasis, initiation refers to platelet aggregation and activation.
F
This is true for amplification.
Regarding physiologic haemostasis, propagation refers to thrombin formation.
F
This is true for initiation.
Regarding physiologic haemostasis, amplification refers to fibrin formation and clot stabilisation.
F
This is true for propagation.
In general, anticoagulation prescribed for secondary thrombotic prophylaxis should not be discontinued for dermatologic surgery procedures.
T
Optimizing anaesthesia, and alleviating anxiety and situational hypertension, will significantly reduce the risk of perioperative bleeding.
T
Clonidine 0.1mg orally can be used with patient who have anxiety accompanied by situational hypertension and its antihypertensive effects last for 2 -4 hours
F
All correct, except lasts for 12 hours
provides antihypertensive, sedative, and anxiolytic effects
Clonidine should be given the day before surgery
F
60 mins
Clonidine should be avoided in patients with a preop systolic pressure less tha 100 mmHg
T
also avoid if pulse less than 60
Oral midazolam 5-10mg will provide rapid anxiolosis (within 20mins) but can cause significant haemodynamic compromise
F
Has no haemodynamic effects
Physical haemostatics include gelatine sponge, oxidised cellulose, microfibrillor collagen haemostat
T
They act as a physical mesh onto which coagulation can occur
Aluminum chloride and trichloroacetic acid are most likely to leave pigment particles which may stain the skin
F
Least likely, unlike silver nitrate or ferric sulphate
Adjuncts to haemostasis include silver nitrate, ferric sulphate (Monsels solution), aluminium chloride or 35% trichloroacetic acid
T
Electrosurgery and suture ligation for haemostasis should be precise to minimize excessive collateral tissue injury.
T
Haemostasis is defined as the arrest of bleeding through physiologic or surgical intervention.
T
The final haemostatic plug derives 20% of its strength from platelets and 80% from the fibrin network.
F
55% from platelets, 45% from fibrin.
Von Willebrand disease is the most common inherited bleeding disorder.
T
Affects up to 1% of the population.
Herbs and medication supplements that affect haemostasis include feverfew, fish oil, garlic, ginger, ginkgo, ginseng, dong quai root, bilberry, chondroitin and vitamin E.
T
The mild anticoagulation effect of vitamin E may be significantly increased when taken with aspirin and garlic.
T
To maximise the vasoconstrictive effects of adrenaline, at least 5 minutes should pass before the first incision.
F
15 mins.