ACC teaching scenarios

Question 1

How is hypovolemic shock categorised ?

Answer 1

• Haemorrhagic : acute reduction ineffective intravascular volume from bleeding (lack of blood = lack of tissue perfusion = hypoxia).
• Non haemorrhagic : reduced effective intravascular volume from body fluid loss other than blood.

Question 2

How will someone with haemorrhagic shock present and why ?

Answer 2

• Tachycardia
• Hypotension
• Tachypnea
• Hypoxia
• Cold peripheries and loss of peripheral pulses

Question 3

How is major haemorrhage defined ?

Answer 3

50% blood loss within 3 hours or at a rate of >150ml/minute

Question 4

What are the stages of hypovolemic shock ?

Answer 4

• Stage 1: loss of 15% of your body’s blood. Blood pressure and heart rate may still be normal at this point.
• Stage 2: loss of 30% of your body’s blood (750 mL to 1,500 mL or up to almost 51 ounces). Your heart rate starts to go up and you start to breathe faster.
• Stage 3: Loss of 40% of your blood (1,500 to 2,000 mL or up to 68 ounces). Your blood pressure drops very low and your heart rate and breathing get faster. You can’t produce much pee.
• Stage 4: loss of more than 40% of your body’s blood Your blood pressure is low and your heart rate is high.

Question 5

What is your immediate management of someone with hypolemic shock ?

Answer 5

• A : check airway is ok.
• B : OXYGEN
• C : get access and do ABG. Get fluids and then blood into them. Make sure its warm

Immediate bloods : FBC, cross match, coagulation screen, biochem.
Ultimately stop any bleeding !

Question 6

What fluids would you give to start resuscitation in hypovolemic shock prior to blood ?

Answer 6

• Hartmans -> isotonic crystalloid solution.

Question 7

What fluids should not be used for resuscitation in hypovolemia ?

Answer 7

• Dextrose : a very small proportion stays intravascularly

Question 8

What blood products are used in major haemorrhage ?

Answer 8

• Packed red blood cells
• FFP (used if prolonged PT/APTT)
• Cryoprecipitate (used for low fibrinogen.

Question 9

How much would you expect one unit of blood (approx. 250mls) to raise the haemoglobin count by?

Answer 9

1g/dl

Question 10

How do you assess severity of IHD prior to surgery?

Answer 10

• Exercise tolerance test
• Angina frequency, pattern and GTN use.
• Any previous ACS or cardiac interventions
• ECG

Question 11

What is used to estimate functional capacity of patients ?

Answer 11

• Duke Activity Status Index (DASI)
• Gives METS = metabolic equivalents. 4 METs needed for surgery

Question 12

what needs check on bloods prior to surgery ?

Answer 12

• Kidney function (eGFR)
• If patient on ACEI may affect kidney function
• Need to be sure he will adequately excrete drugs etc

Question 13

What medications should be stopped preoperatively ?

Answer 13

• Any anticoagulants (e.g. apixaban)

Question 14

What is a complication of GA, especially in those with IHD?

Answer 14

• Perioperative MI/angina/stroke

Question 15

at what Hb level do you consider transfusion following sugery ?

Answer 15

• Active IHD (e.g. chest pain) : 10g/dl
• Stable IHD : 8g/dl (60g/l)

Question 16

why does CPAP help with pulmonary oedema in heary failure ?

Answer 16

CPAP Forces fluid out of the alveoli and allows gas exchange to occur. The issue here is the oedema preventing adequate gas exchange. CPAP will keep the airway open and force out the fluid.

Question 17

if a patient with HF following post op MI does not improve on facial CPAP, what would be done ?

Answer 17

• Intubate

(BiPAP is used more when there is an issue with ventilation itself. Can’t get the air in and out. Ventilatory support is needed. E.g. neuromuscular weakness or you can’t clear the CO2. Negative and positive pressures aids ventilation).