Abdominal Aortic Aneurysm Flashcards
what are the differentials for severe abdo pain, sudden onset, radiating to the back?
perforated viscus
acute pancreatitis
biliary colic
acute mesenteric occlusion
ruptured AAA
what are the 3 main branches of abdominal aorta
super mesenteric, inferior mesenteric and coeliac trunk
how does CO and BP change in patient who is losing blood?
o Body is able to maintain pressure at expense of CO and tissue BF until a large blood volume has been lost
o Only when compensatory mechanisms are unable to cope that BP begins to fall
o Hence, any person esp young and well, who have low BP in the context of acute blood loss are EXTREMELY ill and need urgent care
what is an AAA and what is a ruptured AAA?
dilated abdominal aorta
aneurysm pops and starts bleeding into the abdominal cavity
what is an aneurysm?
dilatation of ALL layers of the arterial wall and most are caused by degenerative disease
loss of intima and elastic fibres in media and associated with lymphocytic infiltration
what are the risk factors for a AAA?
smoking HTN diabetes age >60 being male 4:1 caucasian FH connective tissue disease such as marfans
how does a AAA present
often asymptomatic
symptoms of peripheral vascular disease
non specific abdo pain
visible or palpable pulsation
how do you investigate for a AAA
USS or angiography CT or MRI
examine pulse in all limbs (aneurysm in popliteal also likely)
how do you treat a triple A?
treat reversible risk factors
monitoring size
treat peripheral arterial disease
surgery
what surgery is done for AAA
endovascular stenting (into abdominal aorta to prevent blood from collecting in the aneurysm)
complication = endo-leak
laparoscopic repair and open surgical repair
can also clamp the artery
what happens in a ruptured triple A
risk of rupture increases with diameter
high mortality
presents with pulsatile mass and severe abdo pain, haemodynamic instability, may have generalised shock state and bilateral leg ischaemia
NO delay for imaging, diagnosis of rupture can be confirmed by immediate CT abdomen
what other aneurysms may you see?
thoracic, suprarenal, popliteal
what is the management of major haemorrhages?
recognise blood loss
resuscitate and call for help
stop the bleeding (pressure, reverse anti-coagulants, transexamic acid)
blood samples: group and save then cross match = give blood components as necessary
massive haemorrhage packs (1 and 2)
monitor coagulation tests and move to goal directed
what massive haemorrhage packs 1 and 2
pack 1: 4 units of RBC and 4 units of FFP
pack 2: (given if MH continues)
- 4 units RBC, 4 units of FFP, 1 dose of platelets and 2 packs cryoprecipitates)
what is the patient at risk of after the MH is under control?
patient will be at risk of thrombosis and will require thromboprophylaxis
what is peripheral vascular disease?
atherosclerosis in arteries, can be chronic limb ischaemia or acute limb ischaemia
what is claudication
pain on exertion due to ischaemia, predictable pain that settles swiftly at rest
what is chronic limb ischaemia
ulceration, limb loss as well as rest pain
what is acute ischaemia
emboli, dissection, large vessel thrombosis and the 6 p’s
what are the 6ps?
pale, perishing cold, pulseless, painful, paraesthetic and paralysed (the last 2 are threatening and then non-viable meaning amputation)
what are the risk factors for peripheral vascular disease?
increasing age, male sex, FH
smoking, HTN, cholesterol and diabetes
what are the 4 stages of chronic limb ischaemia
o Fontaine 1: asymptomatic
o Fontaine 2: claudication
o Fontaine 3: rest pain
o Fontaine 4: tissue loss
what is rest pain
o Icy, burning, constant pain in foot
o Worse in evening or elevation due to drop in BP and perfusion pressure in foot is less so wakes them up
o Needs opiates
o Needs this for 2 weeks before diagnosed as critical limb ischaemia
what is tissue loss
gangrene and ulceration
what is the treatment for PVD
o STOP SMOKING o Antiplatelets – aspirin o BP control o Cholesterol reduction – statin o Regular exercise o Lose weight o Tight diabetic control
what is the prognosis for PVD
improves over 6-12 months
MI in next 5 years risk is 30%
what is cerebrovascular disease
atheroma in carotid artery, presenting with stroke, TIA or amaurosis
investigation is duplex for carotid artery stenosis or angiography, MR/CT
treatment is carotid endarterectomy for symptomatic patients
>70% stenosis in ICA is an indication for surgery
what is an aortic dissection
Life-threatening condition: separation in layers of artery wall
Tear in tunica intima; causes blood to flow between layers of the wall of the aorta
Creating false lumen in the aorta
what part of aorta does an AD commonly affect
surrounding ascending and aortic arch
surgical emergency
what are the RF for AD
chronic hypertension, connective tissue disorders such as ehler-danlos, marfans
male, age >65, trauma
how does an AD present
o Tearing chest pain of sudden onset o Sweating, nausea, SOB and weakness o Radiating to the back o Hypertension o Hypotension as dissection becomes more severe = shock
how can you classify an AD
type A: involve the artery before origin of left subclavian, requires surgery
type B: descending thoracic, medically treated
how do you manage an AD
resusc, confirm by imaginng: first line is CT with contrast
urgent surgery: stenting
what is shock
Acute clinical syndrome initiated by ineffective perfusion and cellular hypoxia, resulting in severe dysfunction of organs vital to survival
what is the basic cardio physiology?
learn notes
what are the 4 types of shock?
Hypovolaemic = reduced intravascular volume due to fluid loss
Eg haemorrhage, burns, GI losses, dehydration
• Cardiogeneic – intrinsic cardiac failure of such severity that organ perfusion is compromised eg MI, arrythmias
• Distributive – vasodilation and malperfusion
eg Sepsis, pancreatitis, trauma, anaphylaxis, neurogenic
• Obstructive – failure of circulatory flow
eg Tension pneumothorax, pericardial tamponade, PE
what are the physiological responses to shock?
- Preload falls SV falls CO falls
- To compensate, SNS activates SAN tachycardia and increased contractility SVR or vascular tone increased offset reduction in mean arterial pressure
what would you see in a person with shock?
cold and pale skin
oliguria
confusion and lethargy
possibly metabolic acidosis
how do you manage shock
ABCDE oxygen fluids IV; 2 large bore cannulae bloods: crossmatch ABG treat cause eg MH
aim to prevent irreversible organ failure and injury
what is a crystalloid
contains electrolytes dissolved in water eg normal saline, hartmanns
electrolytes and water distribute easily into ECF so much doesnt stay intravascularly
what is a colloid
large molecules inelectrolyte solution
useful for patients who need a quick increase in circulating volume
what is septic shock
widespread inflammation due to infection
vasodilation and capillary leak
what are the complications of a massive blood transfusion
Transfusion-related acute lung injury (TRALI)
- Rare but serious syndrome (1 in 12,000) characterised by sudden acute respiratory distress following transfusion.
new acute lung injury (ALI) during or within 6 hours after blood product administered
hence req careful coagulation monitoring
what other complications may you see after a transfusion
infection
hypocalcaemia (bc citrate binds to calcium)
haemolytic reactions (rhesus status; due to mismatched blood)
hypothermia
allergy / anaphylaxis
what would you see an an acute haemolytic transfusion reaction
fever, abdominal and chest pain, agitation and hypotension
what is a non-haemolytic febrile reaction
due to WBC HLA antibodies, use paracetamol
what problems will someone in the ICU have when they are discharged?
muscle weakness and wasting nutritional deficiencies sleep disorders inability to swallow effectively microaspiration of food recurrent chest infections
