Sepsis Flashcards
What is sepsis?
This is defined as life-threatening organ dysfunction caused by a dysregulated host response to an infection.
What is the previous definition of sepsis?
Temperature >38 or <36 Heart rate >90 bpm Respiratory rate >20 Altered mental status Leukocytosis
What is septic shock?
Septic shock indicates profound circulatory, cellular and metabolic deterioration and is associated with a greater risk of mortality than with sepsis.
Sepsis can progress rapidly to multi-organ failure and shock and is often fatal.
Aetiology of sepsis
Causative agents vary significantly depending on the region, season and type of unit.
Pathogenic organisms are identified in only around half of cases of sepsis.
Bacteria are identified as the causative organism in 90% of cases where organisms are identified.
E.coli remains the most prevalent pathogen causing sepsis.
Pathophysiology of sepsis
Sepsis is a syndrome comprising an immune system-mediated collection of physiological responses to an infectious agent.
Clinical signs such as fever, tachycardia and hypotension are common.
Activation of the immune system- endothelium and coagulation system- inflammation and organ dysfunction.
Vasodilation leads to absolute reductions in circulating volume.
Increased HR- increased CO and if uncompensated leads to hypoperfusion and shock.
Impaired tissue organ delivery is exacerbated by pericapillary oedema.
Organs may become hypoxic- lactic acidosis which leads to cellular dysfunction and then multi-organ failure.
What does high lactate show in sepsis?
Lactate > 4 causes high risk of circulatory collapse and cardiac arrest.
Refer to ITU if high- give inotropes.
Signs and symptoms of sepsis
The presentation may range from non-specific or non-localised symptoms to severe signs with evidence of multi-organ dysfunction and septic shock. High or low temperature. Tachycardia Tachypnoea Acutely altered mental status Poor capillary refill Mottling of the skin or ashen appearance Signs associated with a specific source of infection Low oxygen sats Arterial hypotension Cyanosis
Risk factors of sepsis
Underlying malignancy Age > 65 years Immunocompromise Haemodialysis Alcoholism DM Recent surgery Breached skin integrity Indwelling lines or catheters I.V drug misuse Pregnancy
How do you identify patients at risk of developing sepsis?
NEWS2
qSOFA score- GCS, systolic BP <100 mm Hg, RR >22
The quick SOFA score (qSOFA) assists health care providers in estimating the risk of morbidity and mortality due to sepsis.
SOFA criteria is now used instead of SIRS criteria due to low specificity.
What is the SOFA score?
The sequential organ failure assessment score (SOFA score), previously known as the sepsis-related organ failure assessment score is used to track a person’s status during the stay in an intensive care unit (ICU) to determine the extent of a person’s organ function or rate of failure.
The score is based on six different scores, one each for the respiratory (paO2), cardiovascular, hepatic (bilirubin), coagulation (platelets), renal (urine output or creatinine) and neurological systems (GCS).
Initial assessment of sepsis
ABCDE
Signs & symptoms of sepsis
Check risk factors for sepsis
Investigations of sepsis
Identify causative organisms (blood cultures, LP if meningitis is suspected)
Evaluate for organ dysfunction (LFTs, FBC, clotting, U&Es, lactate, ABG, CRP and procalcitonin)
Identify the source of infection (CXR and ultrasound. ECG to exclude other differential diagnoses)
Differentials of sepsis
SIRS- non-infectious MI Pericarditis Myocarditis Acute pancreatitis Massive PE Leukaemia Malignant HTN Drug-induced fever and coma
Management of sepsis
Sepsis six- associated mortality reduce by as much as 50% is this is done.
If hypotension persists with a MAP of <65 mmHg, start a vasopressor like noradrenaline via a central venous catheter.
Administer up to 2 litres of fluid as boluses to see if BP responds before referring to ICU in sepsis.
What is sepsis six?
Administer oxygen to maintain target sats.
Take a blood culture and consider other sampling.
Give IV antibiotics- broad spectrum
Start IV fluid- crystalloid 30ml/kg for hypotension or lactate >4 mmol/L
Check lactate levels
Monitor hourly urine output
