NEEED TO FINISH Shock & Sepsis

Question 1

What is shock?

Answer 1

When there is insufficient tissue perfusion.

Question 2

The pathophysiology of shock may be divided into what 5 aetiological groups?

Answer 2

1) septic

2) haemorrhagic

3) neurogenic

4) cardiogenic

5) anaphylactic

Question 3

What is sepsis?

Answer 3

A life-threatening medical emergency, results from a dysregulated host response to infection, leading to systemic inflammation and organ dysfunction.

Question 4

Pathophysiology in sepsis?

Answer 4

1) Immune cells release large amouns of cytokines (e.g TNF) that active immune system –> systemic inflammation and release of nitrous oxide, causing vasodilation

2) Cytokines increase permeability of vessels –> oedema and reduced intravascular volume. Oedema creates a gap between the blood and the tissues, reducing the amount of oxygen that reaches the tissues.

3) Activation of coagulation system –> deposition of fibrin & formation of thrombi –> compromises organ and tissue perfusion.

4) Formation of blood clots consumes platelets and clotting factors, leading to thrombocytopenia (low platelets) and uncontrolled bleeding (haemorrhage) –> DIC

Question 5

How can sepsis lead to disseminated intravascular coagulopathy (DIC)?

Answer 5

The formation of blood clots consumes platelets and clotting factors, leading to thrombocytopenia (low platelets) and uncontrolled bleeding (haemorrhage).

Question 6

How can sepsis lead to metabolic acidosis?

Answer 6

1) Tissues have an inadequate oxygen supply, leading to anaerobic respiration.

2) Lactate levels rise –> metabolic acidosis

Question 7

What are often the most common sources of infection in sepsis?

Answer 7

1) Pneumonia: often strep pneumoniae, haemophilus influenzae, staph. aureus

2) Intra-abdominal: E. coli, Bacteroides species, etc

3) UTIs: frequently caused by E. coli, Klebsiella pneumoniae, and Proteus species.

4) Skin and soft tissue infections: S. aureus and Streptococcus pyogenes are the major pathogens.

5) Bacteremia e.g. originating from indwelling catheters or other medical devices

Question 8

What 2 bacteria are frequently implicated in infections arising from indwelling catheters or other medical devices?

Answer 8

1) Staph. epidermidis

2) coagulase-negative staphylococci implicated

Question 9

What is septic shock?

Answer 9

A more severe form sepsis, technically defined as ‘in which circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone’.

Question 10

What is the qSOFA score?

Answer 10

A bedside prompt that may identify patients with suspected infection who are at greater risk for a poor outcome outside the intensive care unit (ICU).

Question 11

What does the qSOFA score consist of?

Answer 11

1) RR >22/min

2) Altered mentation

3) Systolic blood pressure < 100 mm Hg

Question 12

What qSOFA score indicates someone at a heightened risk of mortality (10% risk)?

Answer 12

> /= 2

Question 13

What is septic shock?

Answer 13

Septic shock occurs when the arterial blood pressure drops despite adequate fluid resuscitation, resulting in organ hypoperfusion.

Anaerobic respiration begins, and the serum lactate level rises.

Question 14

What 2 criteria are required to diagnose septic shock?

Answer 14

1) low mean arterial pressure (<65 mmHg) despite fluid resuscitation (requiring vasopressors)

2) raised serum lactate (>2 mmol/L)

Question 15

Management of septic shock?

Answer 15

1) aggressive treatment with IV fluids

2) escalate to high dependency unit or ICU

3) treatment with vasopressors e.g. noradrenaline

Question 16

What are vasopressors?

Answer 16

Medications that cause vasoconstriction (narrowing of blood vessels), increasing systemic vascular resistance and consequently mean arterial pressure (MAP) –> help to improve tissue perfusion.

Question 17

What is the sepsis-related (or Sequential) Organ Failure Assessment (SOFA) criteria?

Answer 17

Can be used to assess the severity of organ dysfunction, most often in the intensive care unit. It takes into account signs of organ dysfunction:

• Hypoxia
• Increased oxygen requirements
• Requiring mechanical ventilation
• Low platelets (thrombocytopenia)
• Reduce Glasgow Coma Scale (GCS)
• Raised bilirubin
• Reduce blood pressure
• Raised creatinine

Question 18

RIsk factors for sepsis?

Answer 18

Any condition causing immune dysfunction, frailty or a predisposition to infection is a risk factor for sepsis:

• Very young or old patients (under 1 or over 75 years)
• Chronic conditions, such as COPD and diabetes
• Chemotherapy, immunosuppressants or steroids
• Surgery, recent trauma or burns
• Pregnancy and childbirth
• Indwelling medical devices, such as catheters or central lines

Question 19

What is the National Early Warning Score (NEWS2) score?

Answer 19

Used to help identify acutely unwell patients, including those with sepsis.

Question 20

What 6 parameters are measured in the NEWS2 score?

Answer 20

1) RR
2) BP
3) O2 sats
4) Temp
5) HR
6) Consciousness level

Question 21

Give some additional signs of infection possibly seen

Answer 21

1) Signs of potential sources, such as cellulitis, discharge from a wound, cough or dysuria

2) Reduced urine output

3) Mottled skin

4) Cyanosis

5) Arrhythmias, such as new-onset atrial fibrillation

6) A non-blanching rash can indicate meningococcal septicaemia

Question 22

What is often an early sign of sepsis?

Answer 22

Tachypnoea

Question 23

How may elderly present with sepsis?

Answer 23

often present with non-specific findings, such as confusion, drowsiness or simply “off legs”

Question 24

How may neutropenic or immunosuppressed patients present with sepsis?

Answer 24

may have normal observations despite being life-threateningly unwell

Question 25

Investigations in sepsis?

Answer 25

1) Vital signs

2) FBC: for WCC and neutrophils

3) U&Es: for kidney function and AKI

4) LFTs: for liver function and as a possible source of infection

5) CRP

6) Blood glucose

7) Clotting: to assess for DIC

8) Blood cultures: to assess for bacteraemia

9) Blood gas: for lactate, pH and glucose

Question 26

Patients with sepsis should be risk stratified into low, medium and high risk.

Give some examples of ‘high risk’ criteria

Answer 26

1) Acute confusional state

2) Responds only to voice or pain/ unresponsive

3) Systolic B.P <= 90 mmHg (or drop >40 from normal)

4) Heart rate > 130 per minute

5) Respiratory rate >= 25 per minute

6) Needs oxygen to keep SpO2 >=92%

7) Not passed urine in last 18 h/ UO < 0.5 ml/kg/hr

8) Lactate >=2 mmol/l

9) Recent chemo

10) Non-blanching rash, mottled/ ashen/ cyanotic

Question 27

How soon should patients with suspected sepsis be treated?

Answer 27

Within 1 hour of presentation

Question 28

Management of sepsis - ‘sepsis 6’?

Answer 28

B - blood cultures

U - urine output (hourly)

F - IV fluids

A - broad spectrum Abx

L - lactate

O - O2 to maintain oxygen saturation 94-98%

Question 29

What is IV fluid recommendation in sepsis?

Answer 29

Bolus of 500ml crystalloid over less than 15 minutes

Question 30

What is neutropenic sepsis?

Answer 30

May be defined as a neutrophil count of < 0.5 * 10^9 in a patient who is having anticancer treatment and has one of the following:

1) a temperature higher than 38ºC or

2) other signs or symptoms consistent with clinically significant sepsis

Question 31

What is the most common bacteria causing neutropenic sepsis?

Why?

Answer 31

Coagulase-negative, Gram-positive bacteria, particularly Staphylococcus epidermidis –> probably due to the use of indwelling lines in patients with cancer

Question 32

Who is neutropenic sepsis more common in?

Answer 32

Patients having chemo

Question 33

When does neutropenic sepsis commonly occur after chemo?

Answer 33

7-14 days after

Question 34

If it is anticipated that patients are likely to have a neutrophil count of < 0.5 * 109 as a consequence of their treatment, what should they be offered?

Answer 34

A fluoroquinolone

Question 35

Management of neutropenic sepsis?

Answer 35

1) Start empirical antibiotic therapy immediately.

2) There may be a role for G-CSF in selected patients

Question 36

What Abx is often used in neutropenic sepsis?

Answer 36

Piperacillin + tazobactam (Tazocin)

Question 37

Give some medications that can cause neutropenia?

Answer 37

1) chemotherapy

2) methotrexate (for RA)

3) clozapine (for schizophrenia)

4) hydroxychloroquine (for RA)

5) sulfalazine (for RA)

6) carbimazole (for hyperthyroidism)

7) quinine (for malaria)

8) infliximab (a monoclonal antibody used for various autoimmune conditions)

9) rituximab (a monoclonal antibody used for various autoimmune conditions and cancers)

Question 38

What are the 4 major classes of haemorrhagic shock?

Answer 38

Class I
Class II
Class III
Class IV

Question 39

What does the average adult blood volume comprise?

Answer 39

7% of body weight

In 70kg adult, this will equate to 5 litres.

Question 40

Give blood loss for the 4 classes of haemorrhagic shock

Answer 40

Class I: <750ml

Class II: 750-1500ml

Class III: 1500ml-2000ml

Class IV: >2000ml

Question 41

What key symptoms are seen in the 4 classes of haemorrhagic shock?

Answer 41

Class I: normal

Class II: anxious

Class III: confused

Class IV: lethargic

Question 42

In patients suffering from trauma, the most likely cause of shock is haemorrhage.

However, what else can be the cause or occur concomitantly?

Answer 42

1) Tension pneumothorax

2) Spinal cord injury

3) Myocardial contusion

4) Cardiac tamponda

Question 43

In order to generate a palpable femoral pulse, what arterial pressure is required?

Answer 43

> 65 mmHg

Question 44

What does neurogenic shock occur most often after?

Answer 44

Spinal cord transection (usually at a high level).

This results in interruption of the autonomic nervous system.

Question 45

How does spinal cord injury result in shock?

Answer 45

1) There is either decreased sympathetic tone or increased parasympathetic tone

2) The effect is a decrease in peripheral vascular resistance mediated by marked vasodilation.

3) This results in decreased preload which causes decreased cardiac output (Starling’s law)

4) There is decreased peripheral tissue perfusion –> shock

Question 46

Management of neurogenic shock?

Answer 46

Vasoconstrictors are used to return vascular tone to normal (in contrast to many other types of peripheral shock).

Question 47

What is the main cause of cardiogenic shock in medical patients?

Answer 47

IHD

Question 48

What is the main cause of cardiogenic shock in traumatic patients?

Answer 48

Direct myocardial trauma or contusion.