Week 1: Sepsis Flashcards
Define sepsis
A potentially life threatening condition caused by a dysregulated host response to infection, resulting in an acute systemic immune response.
Leads to fatal organ and tissue injury
Define septic shock
Sepsis, with a significant increase in mortality risk due to circulatory and cellular/metabolic abnormalities.
When blood pressure drops to a dangerously low level =<65mmHG and lactate remains => 2mmol/L after intervention and organ failure starts after an infection.
How common is septic shock?
Occurs in 30% of sepsis patients
What are the outcomes like for sepsis patients?
Mortality ranges from 10-30% for sepsis patient, higher 50% in septic shock.
Many survivors will suffer from hsopital readmission, early death, physical and neurocognitive dysfunction, mood disorders and low quality of life.
Why are sepsis death statistics important to public health?
Leading cause of death in hospitalised patients
Nearly 20% of all global deaths.
What are some risk factors for sepsis?
Extreme age
Male sex
Black patients
Chronic diseases - HIV and cancer
Immunosuppressed patients
Prior organ dysfunction
Delay in treatment and diagnosis
Recent surgery or invasive procedure
Pregnancy women, recent birth or miscarriage
What are the two classification or sepsis regarding aetiology?
Hospital acquired
Community acquired
What are the most common types of infection in sepsis?
Pneumonia
Intra-abdominal infections
Genitourinary infections (UTIs)
Follwed by endocarditis, meningitis and skin infections
How useful are blood cultures in sepsis diagnosis?
1/3 of blood cultures for sepsis patients will come back positive.
What are the most common gram-positive pathogens causing sepsis?
Staphylococcus aureus
Staphylococcus pneumonia
What are the most common gram negative pathogens that cause sepsis?
E.coli
Klebsiella spp
Pseudomonas aeruginosa
What type of pathogens are often responsible for causing sepsis?
79% bacterial
20% fungal
1% viral
What is the difference between microvascular and macrovascular?
Microvascular involves small vessels such as capillaries
Macrovascular involves large vessels such as arteries or veins.
Describe the pathophysiological process by which sepsis brings about vascular changes in the body.
Pathogen from infection. PAMPs recognised by PRRs triggering the inflammatory response.
This leads to tissue damage and necrotic cell death.
Release of DAMPs further activates leukocytes and promotes inflammation.
Microvascular changes include endothelial cell dysfunction, coagulation and complement activation.
Macrovascular changes include vasodilation and hypotension.
What are the pathophysiological consequences of the vascular changes in sepsis?
Microvascular and macrovascular changes result in vascular leak cuasing edema and intravascular volume depletion.
This reduces the oxygen supply to the tissue leading to increased glycolysis (hence higher lactate levels), leads to a build up a reactive oxygen species causing mitochondrial damage and organ damage.
How does sepsis affect the kidneys?
Can cause acute kidney injury due to:
Decreased urinary output
Uremia (waste products build up in blood)
Ileus (aversion to oral intake due to lack of emptying GIT)
How can liver failure be identified in sepsis?
Elevated liver enzymes
What makes up the sepsis 6?
Take blood cultures - Give IV antibiotics
Take lactate levels - Give oxygen
Take Urine Output - Give IV fluids
What is the purpose of taking blood cultures in the sepsis 6? What else might you also do to fit this purpose?
Peripheral blood sample to identify source of infection
May also take a urine dispstick, CSF sample or chest X-ray (pneumonia)
What is the example guidance of how to screen for sepsis?
- combined NEWS of 5+, single NEWS 3 or patient looks unwell
- Possibly an infection?
- one red flag present
- Or two amber flags and lactate level above 2mmols/L or Acute Kidney INJury
What is considered a red flag for sepsis?
Systolic BP below 90mmHg
Heart rate above 130 bpm
RR above 24 bpm
Require oxygen
Non-blanching rash
Not passed urine in the last 18hours
Urine output less than 0.5ml/kg/hr
Lactate => 2mmol/L
Chemotherapy within 6 weeks
How soon after sepsis diagnosis should treatment begin?
Within 1 hour