Pathophysiology and Treatment of Sepsis Flashcards
What is sepsis?
Life-threatening oragn dysfunction caused by a dysregulated host response to infection
What is septic shock?
A subset of sepsis in which particularly profound circulatory, cellular and metabolic abnormalities are associated with greater risk of mortality
Who is at risk of sepsis?
- Very young and very old
- impaired immune system
- surgery in the last 6 weeks
- breach of skin integrity
- misuse of IV drugs
- indwelling lines or catheters
- Women who are pregnant, given birth or had a termination or miscarriage in the last 6 weeks
- Neonates
What is sepsis caused by?
ANYTHING
- Respiratory
- Abdomen
- Bloodstream
- skin
- urinary system
- UNKNOWN
what are the 9 key causative pathogens associated with sepsis?
- Neisseria meningitidis
- Streptococcus pneumoniae
- Streptococcus pyogenes
- Staphylococcus aureus (including MRSA)
- Salmonella typhimurium
- Klebsiella pneumoniae
- Gram negative bacilli
- Candida species
- Asplenics are at risk of infection by encapsulated organisms
Breaches of Host barrier integrity
- physical barriers
- skin
- mucous membranes
- Breaches may be obvious:
- catheters
- wounds
- burns
- thorn pricks
- bites
- Breaches may be more subtle - epithelial cell damage
What are the 5 main factors affecting infection?
- virulence of organism
- bioburden
- portal of entry
- host susceptibility
- temporal evolution
What is the first line of defence against pathogen insult?
host innate immunity
What are the main aspects of the host innate immunity?
- Complement cascade
- Mannose-binding lectin
- Phagocytes
- Toll-like receptors (TLRs)
- Nucleotide binding oligomerisation domain receptors (NLRs)
What are the main inflammatory markers initiated by the host innate immune system?
- Interlukins
- Tumour necrosis factor alpha
- Reactive oxygen species
What does TLR4 recognise and what can this recognise
LPS
Present in all gram negative bacteria
What are the effects of TNFalpha and IL-1 on the CVS?
- Generalised vasodilation (NO)
- Increased vascular permeability (activated leukocytes) - bradykinin and histamine release
- Intravascular fluid loss
- myocardial depression (tissue hypoxia)
- circulatory shock
- cytokine causes mast cells to degranulate
What occurs in acute phase response
- Fever
- Hypotension
- Increased HR
- Corticosteriod and ACHT release
- Released of neutrophils
Who to screen for sepsis?
- Presents with unexplained illness
- Look unwell and has a likely infective cause OR presents with a parameter score or aggregate score of 4 or higher on NEWS
What are the symptoms of systemic inflammatory response syndrome?
- Fever (>38) or hypothermia (<36)
- Tachycardia
- Tachypnooea (>20)
- Leucocytosis
What should be checked prior to carrying out the sepsis six?
- ABC
What is the sepsis six (BUFALO)
- Blood cultures
- Urine output
- IV fluids
- Broad spectrum antibiotics
- Lactate and haemoglobin
- High flow Oxygen
What should be given in a respiratory infection?
broad spectrum and consider pseudamonas or MRSA
What should be given in a urinary infection?
gram negative and pseudamonas
What should be given in a abdominal infection?
gram negtaive/positive anerobes
What should be given in a soft tissue infection?
Gram negtaive/positive and anerobes
What should be given in a CNS infection?
menigitis
What antibiotics is given if meningococcal disease is suspected?
IV/IM benzylpenicillin or cefotaxime
Short term complications of sepsis
organ dysfunction and coagulation disorders
long term complications of sepsis
neurlogical dysfunction, increased mortality rate for at least a year
