1.2i Resuscitation (Shock and Sepsis)

Question 1

What is the formula for cardiac output?

Answer 1

CO = SV x HR

Question 2

Briefly explain how hypovolaemic shock and distributive shock affect blood volume.

Answer 2

Question 3

What is the formula for blood pressure?

Explain how this is affected in cardiogenic shock or sepsis.

Answer 3

BP = CO x SVR

• In sepsis, BP (low) = CO (increased) x SVR (decreased), due to widespread vasoconstriction
• In MI, BP (low) = CO (decreased) x SVR (increased

Question 4

Describe the physiology of shock from hypovolaemic, cardiogenic and obstructive causes.

Answer 4

There is a widespread sympathetic response, causing vasoconstriction (pale, clammy), which increases SVR.

CO is decreased because of reduced blood volume, cardiac failure or mechanical or physiological obstruction.

The decreased CO and increased SVR causes decreased BP, leading to a narrow pulse pressure, reduced MAP.

The heart may be tachycardiac as a compensatory measure.

Question 5

Describe the physiology of shock from distributive mechanisms.

Answer 5

Peripheral resistance (SVR) is low due to widespread vasodilation, e.g. anaphylaxis.

CO is high, MAP is low, there is a wide pulse pressure.

If vasoconstriction then occurs, as a result of decreased CO, this is called ‘cold shock’ and is ominous.

Question 6

Question:

In paediatrics, the satisfactory urine output (mL/kg) increases the younger the patient is.

True or False?

Answer 6

True.

• Adults: 0.5mL/kg
• Children: 1mL/kg
• Very young children: 2mL/kg

Question 7

Describe the bolus size.

Answer 7

20mL/kg is a rough rule of thumb, but exercise caution in the elderly, those with poor LV failure.

Question 8

When should you consider pressors?

Answer 8

After 2L of fluid and if it is still not responding, start thinking about pressors.

Question 9

Answer 9

Question 10

Question: The pitfalls of shock…

Answer 10

Question 11

What are the 2 types of hypovolaemic shock?

Answer 11

Haemorrhagic and non-haemorrhagic.

Question 12

How much fluid is lost in shock?

Answer 12

7% in adults, 9% in children.

Question 13

What are the causes of non-haemorrhagic hypovolaemic shock?

Answer 13

• GI losses, e.g. gastroenteritis
• Renal losses, e.g. osmotic diuresis
• Skin losses, e.g. burns
• Third space losses, e.g. pancreatitis

Question 14

What is the target MAP for those with shock?

Answer 14

65mmHg, helps to perfuse vital organs.

Question 15

What are the trends you might expect to see in vitals, cognition, urine output in worsening stages of shock?

What types of fluid should you consider?

Answer 15

Question 16

What are the features of Class I haemorrhagic shock?

Answer 16

Question 17

What are the features of Class II haemorrhagic shock?

Answer 17

Question 18

What are the features of Class III haemorrhagic shock?

Answer 18

Question 19

What are the features of Class IV haemorrhagic shock?

Answer 19

Question 20

How to evaluate response to fluid?

Answer 20

• Rapid responder: <20% blood loss, responds to initial fluid bolus.
• Transient responder: 20-40% blood loss, responds to initial bolus, then worsens. Give crystalloids and blood.
• Minimal to no response: >40% blood loss, initiate massive transfusion protocol and seek urgent OT.

Question 21

What are common complications of hyper-resuscitation?

Answer 21

• Fluid overload, pulmonary oedema
• Acidosis, coagulopathy, hypothermia

Question 22

When should you consider arterial/central line monitoring?

Answer 22

• Fluid resuscitation with vasopressors/inotropes
• Multi-organ failure

Question 23

The most common cause of hypovolaemic shock is?

Answer 23

Question 24

What are the principles of treatment for cardiogenic shock?

Answer 24

• Treat cause, e.g. MI, toxins, arrhythmia
• Inotropes
• ECMO
• Theatre - intra-aortic balloon pump, stent, urgent angiography…

Question 25

Explain what the SOFA score is.

Answer 25

SOFA score \>2 means increased risk of bad outcomes. 1. O2 2. Coagulation 3. Bilirubin 4. Blood pressure 5. GCS 6. Renal creatinine/output

Question 26

Question: The pitfalls of sepsis management...

Answer 26

* Severe sepsis may have normal observations, especially in the young and sick, as they may compensate and crash suddenly * Elderly patients may have 'blunted' responses

Question 27

Describe the basic principles of managing resuscitation and sepsis.

Answer 27

* A is for Airway/Adrenaline* * B is for Breathing* * Assisted breathing may decrease venous return, so always keep well hydrated * Consider treating arrhythmias to help with circulation *Circulation* 1. Bolus * Healthy adults - 1L stat, followed by 2-3L * Children - 20mL/kg bolus 2. After 2L, consider vasopressors * Adrenaline in anaphylaxis * Noradrenaline 6mg in 100mL normal saline, then 5mL/hour and titrate 3. Steroids * Consider if patient is normally on steroids, as adrenal suppression may be an issue * 100mg hydrocortisone or 10mg dexamethasone IV * For relative adrenal insufficiency consult your senior colleagues 4. Antibiotic therapy * Blood cultures * Empirical antibiotics * Treat source, e.g. drain collection

Question 28

Question: An 80 y.o. with urosepsis...

Answer 28

Question 29

Question: All the selections below...

Answer 29

PE is an **obstructive** form of shock.

Question 30

What is obstructive shock? What causes obstructive shock?

Answer 30

Obstructive shock causes impairment of: 1. Cardiac filling 2. Cardiac output 3. Both Common causes include tension pneumothorax, pericardial tamponade and massive pulmonary embolism

Question 31

What is the management of tension pneumothorax?

Answer 31

Clinical diagnosis, do not wait for XR. Rapid needle decompression, followed by re-XR.

Question 32

What are the causes of pericardial tamponade?

Answer 32

\>200mL fluid in pericardial sac, usually acute. **_Acute Causes_** 1. Penetrating trauma, e.g. iatrogenic (PPM leads) 2. Ruptured myocardium, e.g. MI 3. Type A aortic dissection **_Chronic Causes_** 1. Pericarditis 2. Malignancy 3. Connective tissue disease 4. Infection, TB, HIV

Question 33

What are the clinical signs of percardial tamponade?

Answer 33

Sinus tachycardia, dyspnoea. Pulsus paradoxus. Electrical alternans on ECG. **_Beck's Triad_** (Late, but highly specific.) * Hypotension * JVP engorgement * Muffled heart sounds

Question 34

What is pulses paradoxus?

Answer 34

Pulsus paradoxus, also paradoxic pulse or paradoxical pulse, is an abnormally large decrease in stroke volume, systolic blood pressure and pulse wave amplitude during inspiration. The normal fall in pressure is less than 10 mmHg. When the drop is more than 10 mmHg, it is referred to as pulsus paradoxus. Measure BP manually, note the mmHg when the Koratkoff sounds are first heard on expiration. Repeat, and note the mmHg when the Koratkoff sounds are first heard on inspiration.

Question 35

What is ECG electrical alternans? What does it indicate?

Answer 35

Electrical alternans is an electrocardiographic phenomenon of alternation of QRS complex amplitude or axis between beats and a possible wandering base-line. It indicates **_pericardial tamponade_**.

Question 36

What is the treatment for pericardial tamponade?

Answer 36

Diagnose with echocardiography. Small fluid boluses to maintain blood pressure. Needle pericardiocentesis +/- placement of catheter. Patient should be sitting at 45 degrees, to move the heart to the anterior chest wall.

Question 37

Explain the basic approach for a needle pericardiocentesis.

Answer 37

2 basic approaches, ACEM recommends the subcostal (classical) approach, but apical and parasternal approaches are also possible. Parasternal approach not recommended due to high risk of lacerating the left anterior descending artery... Tutorial:[https://www.youtube.com/watch?v=M4vHEr25yFk](https://www.youtube.com/watch?v=M4vHEr25yFk)

Question 38

Question: Tension pneumothorax causes obstructive shock. True or false?

Answer 38

Obstructive shock, which leads to haemodynamic compromise.