18. AAA lectures Flashcards
Blood transfusion, intro to vascular disease, management of shock
What are the main early signs that someone has significant blood loss
clinical shock so high HR low BP
When stopping a catastrophic bleed and someone is on warfarin for example, how do you reverse the action of the warfarin
with PCC - prothrombin complex concentrate
what anti-fibronoltyic agent helps to stabilise blood clotting and should be given within the first hour of haemorrhage occurring
tranexamic acid
when ordering blood which blood type would you use;
a) in an extreme emergency
b) if you can wait about 15 minutes from the sample arriving in the lab
C) the safest product if time allows (around 45-60mins)
a) group O RhD negative
b) group specific (ABO and RhD compatible)
c) crossmatched (fully screened for antibodies)
What are the components of pack 1 of the major haemorrhage pack
4 units of red cells
4 units of fresh frozen plasma (FFP)
what are the components of pack 2 of the major haemorrhage pack if the bleeding continues
4 units of red cells
4 units of FFP
1 dose platelets
2 packs of cryoprecipitate
once the haemorrhage is under control, what is the patient at risk of
thrombosis and so they will eventually need thromboprophylaxis
when you generally look at the patient in a vascular examination what things do you comment on (in notes you’ll see it abbreviated to An/J/Cy/Cl
no anaemia, jaundice, cyanosis and clubbing
if someones femoral pulse is rock hard what does this suggest
calcification
Again what are the 6 Ps in critical limb ischemia
pale
perishing cold
pulseless
painful
parenthetic
paralysed
in critical skin Ischaemia which are the most worrying signs (which of the 6ps)
Paraesthetic (muscle tenderness)
paralysed (numb mottled)
in chronic ischemia what does the Fontaine classifications I-IV mean
I - asymptomatic
II- claudication
III- rest pain
IV- tissue loss
what is claudication
aching muscles on effort
predictable
worse on hills, with loads, at speed
settles swiftly with rest
what are the main treatment options for peripheral vascular disease
- Stop smoking
- Antiplatelet therapy (aspirin 75mg od)
- Blood pressure control (sBP less than 140)
- Cholesterol reduction
- Regular exercise
- Weight loss
- Controlled diabetes
In cerebrovascular disease what are the main issues.
atheroma in the carotid artery
can lead to stroke, TIA (stroke symptoms the recover within 24 hours), amaurosis (transient blindness in ipsilateral eye)
what are the investigations for cerebrovascular disease
Carotid duplex scan or angiography
what are the indications for a carotid endarterectomy
symptomatic patients within the past 6 months of symptoms
arterial disease greater than 70%. stenosis of the ICA
must be fit for surgery and have at least a 2 year life expectancy
What is the difference between abnormal dilation of an artery and ectasia
abnormal dilation of an artery is greater than 50% of its diameter
ectasia is dilation of up to 50%
what is arteriomegaly
generalise dilation of the arteries
what is the main aetiology of aneurysm
Atherosclerotic meaning you get it with age
mycotic meaning you get it from an infection of the arterial wall
connective tissue disorder such as marfans or Ehlers-Danlos syndromes (EDS)
the shape of an aneurysm can be described as fusiform or saccular, what is the difference
saccular means asymmetrical dilatation whereas fusiform is symmetrical
fill out the normal transverse diameter sizes for the following;
a) a normal aorta
b) ectasia
c) small AAA
d) large AAA
a) 2.5 cm
b) less than 3.5cm
c) less than 4.5
d) greater than 5.5 cm
what is your stereotypical at risk patient of AAA
males that are 60 years or older who are hypertensive, smokers and have a FH of AAA
what are the main surgical options for AAA and what are the cons of each one
- open surgery: replace the affected segment with plastic graft, rube or bifurcate
- major cardiovascular stress and mortality is 5% - end-vascular surgery/repaire (EVAR): reline the aorta
- only 70% of aneurysm are suitable for this type of treatment and a lot of people get an endoleak
what triad would make you think of an AAA rupture
collapse
hypotension
lower back/flank pain
After correction of an AAA, what are the two most common causes of mortality
acute renal insufficiency
myocardial infarction
How do you define shock
acute clinical syndrome initiated by ineffective perfusion and cellular hypoxia, resulting in severe dysfunction of organs vital to survival
what are the key features of shock
o Acute tissue/organ hypo-perfusion o Impaired delivery of oxygen to cells o Supply inadequate to meet demand o Generalised cellular hypoxia o Consequences for cellular respiration o Haemodynamic abnormalities but shock isn’t simply the presence of hypotension
? x ? = cardiac output
HR X SV
? X ? = mean arterial pressure
CO x vascular tone
what are the 4 types of shock
hypovolaemic - reduced intravascular volume
distributive- vasodilation and malperfusion
cardiogenic- intrinsic cardiac (pump) failure
obstructive- failure of circulatory flow
give some examples of hypovolaemic shock
haemorrhage
burns
GI losses ( vomiting, diarrhoea, fistula)
dehydration (heat exposure, polyuria DKA)
give some examples of distributive shock
systemic inflammatory response syndrome (SIRS) related - sepsis, pancreatitis, trauma, burns
neurogenic- spinal cord injury
Anaphylacxis
give some examples of cardiogenic shock
myocardial infarction/ischaemia
arrhythmia
acute valve pathology.
give some examples of obstructive shock
tension pneumothorax
pericardial tamponade
pulmonary embolism
what is the physiological response of hypovolaemia
- Sympathetic system activated (via the baroreceptors)
- Adrenal catecholamine release
- Compensatory cardiovascular responses
- Sodium and water retention
- Coagulation system activation
- Cortisol release
Give some signs of organ hypo-perfusion
o Skin
o Oliguria
o Cognitive changes
o Metabolic acidosis
Give some examples of crystalloids
normal saline
hartmanns
ringers lactate
glucose solutions
give some examples of colloids
Gelofusine starch dextran blood plasma platelets
in shock what are the important diagnosises that need to be ruled out
tension pneumothorax
pericardial tamponade
PE
Acute MI
what medication can you give to increase the contractility of the heart
ionotropes
A massive transfusion is defined as more than _____ bags in 24 hours or more than ______ bags in one hour
10 bags in 24 hours
4 bags in an hour
Which pathway does the PT time look at
extrinsic pathway - increased in liver disease
which pathway does the APTT time look at
intrinsic pathway
for clotting to occur what 2 cells do you need in your body
- one with TF (which is usually hidden in a healthy blood vessel) such as fibroblasts and macrophages
- platelets
what is DIC
disseminated intravascular coagulopathy
- unregulated clots and lysis
- blood clots form within the blood vessel and as clotting factors and platelets are used up, bleeding may occur
whilst on ICU what is a patient at risk of developing after a massive haemorrhage
acute lung injury
renal dysfunction
DIC
What is the issue with clotting associated with massive blood transfusion
dilution of platelets and clotting factors are recognised causes
• Transfused associated acute lung injury (TRALI)
• Transfusion associated circulatory overload (TACO)
what are the main issues associated with prolonged stay on ICU
o Muscle weakness and wasting o Nutritional deficiencies o Sleep disorders o Inability to swallow effectively and micro aspiration of food o Recurrent chest infections
