Sepsis and septic shock

Question 1

define sepsis

Answer 1

Sepsis is defined as life-threatening organ dysfunction caused by dysregulated host response to infection, an organism enters the bloodstream creating a septic state.

Question 2

define septic shock

Answer 2

Septic shock can be identified with a clinical construct of sepsis with persisting hypotension requiring vasopressors to maintain MAP >65mmHg and having a serum lactate of >2mmol/l despite adequate volume resuscitation

Question 3

what does qSOFA consist of?

Answer 3

hypotension <100 systolic, altered mental status, tachypnea >22RR. A SCORE OF 2 OR MORE SUGGESTS A GREATER RISK OF A POOR OUTCOME

Question 4

what is a SOFA score?

Answer 4

pao2, GCS, MAP, serum creatinine or urine output, bilirubin, platelet count.

Question 5

despite adequate fluid resucitation when should you suspect sespis has progressed to septic shock?

Answer 5

vassopressors required to maintain MAP over 65mmhg, serum lactate over 2

Question 6

how much does mortality increase for each hours delay of abx administration in septic shock?

Answer 6

7.60%

Question 7

pathophysiology of sepsis

Answer 7

similar to immunosuppression: loss of hypersensitivity, inability to clear infection, predisposition to nosocomial infection

Question 8

what are the 3 phases in the pathogenesis of sepsis?

Answer 8

release of bascterial toxins, release of mediators, effects of specific excessive mediators

Question 9

describe what happens in phase 1

Answer 9

Bacterial invasion into body tissues is a source of dangerous toxins, May or may not be neutralised and cleared by existing immune system

Question 10

what are commonly released toxins

Answer 10

Gram negative = Lipopolysaccharide (LPS)
Gram positive = Microbial-associated molecular pattern (MAMP), Lipoteichoic acid, Muramyl dipeptides, Superantigens = Staphylococcal toxic shock syndrome toxin (TSST), Streptococcal exotoxins

Question 11

describe what happens in phase 2

Answer 11

effects of infection due to endo/exo toxin release, mediator role on sepsis (endo - LTA don’t need binding proteins to bind to macrophages) (exo - pro-inflammatory response)

Question 12

what do proinflammatory mediators do? (inflammatory response that characterises sepsis)

Answer 12

Promote endothelial cell – leukocyte adhesion, Release of arachidonic acid metabolites, Complement activation, Vasodilatation of blood vessels by NO, Increase coagulation by release of tissue factors and membrane coagulants, Cause hyperthermia

Question 13

what is a compensatory anti-inflammatory reaction?

Answer 13

can cause immunoparalysis

Question 14

what do anti-inflammatory mediators do?

Answer 14

Inhibit TNF alpha, Augment acute phase reaction, Inhibit activation of coagulation system, Provide negative feedback mechanisms to pro-inflammatory mediators

Question 15

what are the Clinical features of sepsis?

Answer 15

• Fever >38 degrees – chills, rigors, flushes, cold sweats, night sweats
• Hypothermia < 36 degrees – especially in elderly and children (anti-inflammatory response)
• Tachycardia >90bpm
• Tachypnoea >20/min
• Altered mental state
• Hyperglycaemia >8mmol/l
Arterial hypotension (systolic <90mmHg or MAP <70mmHg)
SvO2 >70%

Question 16

what are thhe changes in inflammatory variables in sepsis

Answer 16

Leucocytosis (WCC > 12,000/ml)
Leucopenia (WCC < 4,000/ml)
Normal WCC with greater than 10% immature forms
High CRP
High procalcitonin

Question 17

what are the changes in organ dysfunction variables in sepsis?

Answer 17

Arterial hypoxaemia (PaO2/FiO2 < 50mmHg), Oliguria (<0.5ml/kg/h), Creatinine increase compared to baseline, Coagulation abnormalities (PT >1.5 or APTT >60s), Ileus, Thrombocytopenia (<150,000/ml), Hyperbilirubinaemia.

Question 18

tissue perfusion variables…

Answer 18

high lactate and skin mottling and reduced capillary perfusion

Question 19

factors affecting sy and sx of sepsis…

Answer 19

gram of bacteria, age, comorbidities, immunosupression, previous surgery, occupation, travel

Question 20

What is the SEPSIS 6?

Answer 20

Take –> blood cultures, blood lactate, measure urine output
Give –> o2 aim for sats off 94-98%, iv abx, iv fluid. (type of empirical ABX given depending on the situation -amox, penc, metrondiazole, if ellegies give vanc)

Question 21

what is lactate a marker of?

Answer 21

generalised hypoperfusion, severe sepsis, pooer prognosis. Type a - hypoperfusion, type b - Mitochondrial toxins, Alcohol, Malignancy, metabolism errors

Question 22

how much fluid is appropriate?

Answer 22

30ml/kg e.g. 2.1L 70kg patient

Question 23

what to consider when giving abx…

Answer 23

allergies, mrsa, esbl, cpe, abx toxicity, interactions.

Question 24

when to consider HDU referral?

Answer 24

low bp responsive to fluids, lactate over 2 despite fluids, elevated creatinine, oliguria, liver dysfunction, bilateral infiltrates, hypoxaemia.

Question 25

Case 1

Answer 25

55m, DM, smoker, IHD, Admitted through Emergency Department with fever, nausea, vomiting and abdominal pain x 4 hours, riased bp, pulse and resp rate, tender epigastrium, no rebound, BS present, WCC 15,600, tx in a and e - sepsis 6, Started on Amoxicillin, Gentamicin and Metronidazole for intra-abdominal sepsis
6 hours later patient failed to improve
Admitted with SIRS, On post-take round another blood test was carried out, Serum amylase 1450, Diagnosed as Acute pancreatitis, Antibiotics stopped and patient transferred to surgery for further management

Question 26

Case 2

Answer 26

68 year old woman admitted with worsening shortness of breath
History of IHD, CVA and bed bound
On examination: Alert, Temp 38oC, Resp rate 26/min, pulse 120/min irreg, BP 85/60, Chest dullness right base
Pneumonia CURB65 score - confusion, >7ureaN2, >30RR, DIASTOLIC <60 SYSTOLIC <90, over 65yo. out of 5, 3/5 is high risk of death.