Sepsis Flashcards
(48 cards)
What in sepsis/ infection causes the increase in core temperature
Macrophages, WBCs and injured tissue release pyrogens that act directly on the hypothalamus altering the internal thermostat to a higher temperature.
Examples of heat conserving mechanisms and their function
Vasoconstriction- directs blood away from skin surface, back into central circulation, to prevent heat loss from radiation and convection
Shivering- creates heat
Definition of a CRP test
C-reactive protein is a plasma protein who’s concentration increases during an inflammatory response
What are the 6 diagnostic indicators of sepsis?
Elevated temperature. Warm dry skin. Bouncing pulse. Raised WBC count. Raised C-reactive protein. Positive blood cultures.
Pathway of inflammatory response from injury to healing
Injury
Histamine kinin release
White blood cell release with capillary leak
Debris phagocytosis with clotting and oedema
Redness, swelling, heat and pain
Blood supply and immobility
Healing
What is the purpose of inflammation?
Homeostatic response that aims to protect against infection
What is the tunica intima and what does it release during systemic inflammation?
Inner most layer of the arteries and veins.
Releases vasoactive chemicals
What do vasoactive chemicals do?
Vasodilation
Increase capillary permeability
Triggers clotting
Blood vessel capacity increases whilst central blood volume is decreased
Compromise of perfusion to organs
The state of pro-coagulation facilitates thrombus formation
Neutrophil activation increases oxygen consumption
Definition of sepsis
Life threatening organ dysfunction caused by a dysregulated response to infection
What happens in a dysregulated response to infection? And what is it known as?
The regulation of the inflammatory response has been lost resulting in high levels of pro-inflammatory mediators.
Systemic inflammatory response syndrome
How sepsis differ from infection?
Dysregulated inflammatory response and the presence of multi organ dysfunction.
What in the blood triggers the release of mediators from epithelial cells of the blood vessels?
Pathogens
What are example mediators?
Tumour necrosis necrosis factor
Interleukins
Nitric oxide
Platelet activating factors
What does the release of mediators trigger? 4things
Increased capillary permeability
Activation of the clotting cascade
Vasodilation
Neutrophil mobilisation
What in severe infection reduces cardiac output?
Radical oxide compounds
Following sepsis what are the clinical signs of septic shock?
Sepsis with persistent hypotension requiring vasopressors.
Lactate of more than 2mmol/L despite fluid resus
What are the systemic effects of sepsis?
Hypotension
Poor tissue perfusion leading to hypoxia
Free radical formation increasing capillary permeability resulting in hypovolaemia and odema
Leukocyte activation
Erythrocyte damage
Increased blood viscosity
Disseminated intravascular coagulation
In terms of heart rate, capillary permeability and fluid distribution what occurs during systemic inflammation? And why?
Heart rate increases to increase oxygen delivery to tissues
Vascular walls become more permeable allowing plasma proteins to seep out
Fluid moves from the intracellular and circulatory space into interstitial space
What is acute respiratory distress syndrome?
Wide spread inflammation of lungs
What does tachypnoea lead to?
Respiratory alkalosis
What are the 3 abnormal blood results that indicate renal failure?
Metabolic acidosis.
Raised urea and creatinine
Hyperkalaemia
What is tested for in the blood as an indication of renal failure?
Creatinine
What is creatinine a biproduct of?
Muscle metabolism.
Why does infection/illness cause transient hyperglycaemia?
Stress response to critical illness and chemicals such as corticosteroids and adrenaline.
