Other/general Flashcards
What are the 4 Heat loss mechanisms?
- Conduction: body surface in direct contact with a solid object - depends on thermal conduction of that object as well as amount of body surface area in contact with the object (EX: dog in metal kennel with no blankets- heat loss)
- Convection: heat transfer from body to surrounding air or water- water is more effective medium than air for convective heat transfer (water to cool down dog; peripheral vasodilation can increase convection)
- Radiation: electromagnetic energy that is exchanged btw body and surrounding objects - occurs independently of air temp or velocity (heat from sun, objects around patient)
- Evaporation: heat loss with moisture when environmental temp is equal to or exceeds skin temp (panting)
What are the different Mechanisms of edema formation?
- Venous hypertension
- Hypoproteinemia
- Impaired lymph flow
- Increased microvascular permeability
- Increased negativity of interstitial fluid pressure
How does the body protect itself from edema formation (antiedema mechanisms)?
- increasewd interstitial hydrostatic pressure
- increased lymph flow
- Decreased interstitial colloid osmotic pressure
- increased trans-serosal flow in organs with potential spaces
Sensitivity
SnNout: A test with a high sensitivity value (Sn) that, when negative (N), helps to rule out a disease (out).
Arterial Chemoreceptors
Increased firing with: decreased pH, increased CO2, and decreased O2
In carotid body: join sinus N–> glossopharyngeal (same route as baroreceptors)
SOFA Score
Assume every patietn is 0. Score>/= 2 assd with 10% increase mortality (human defines sepsis)
qSOFA
-from sepsis3
RR>/=22 bpm
Altered mentation
SBP </=100mmHg
Aldosterone (stimuli, & effects)
- stimulated release by decreased renal blood flow or blood volume –> stimulates RAAS–> increased aldo secretion
Effect of aldo:
- Increased reabsorption of Na in distal tubule–> inc water reabsorption
- Increased K and H excretion
- Pro inflammatory and profibrotic effects which may lead to progression of renal disease, vascular thrombosis and fibrosis
- Peripheral vasoconstriction from Angio II
Proinflamm cytoikines of sepsis
**TNFalpha
IL-1
IL-6
IL-8
IFNgamma
CARS
- Compensatory anti-inflammatorty response syndrome
IL-10
TGFbeta
IL-13
IL-4
+/- glucocorticoids
Gram neg sepsis pathogenesis
LPS binds LBP (LPS binding protein) –> complex bind to CD14 on macrophage –> initiated signaling via TLR to neucleus for transcription of cytokines (TNFa, IL1, IL6,IL8 &IFNg) & counterinflamma (IL4, IL10, IL13, TGFb, roids)
Gram + sepsis pathogenesis
Gram+ exotoxins –> act as superantigens –> stimulate sidespread Tcell activation –> uncontrolled release IFNgamma and TNF alpha
Tumor lysis syndrome
-Destruction of tumor cells –> increased K & phosphorus extracellularly
- Purine release from tumor cells –> inc uric acid –> met acidosis & renal impairment
- may occur within hours or days after therapy
CS: lethargy, v/d, shock, decreased HR, hyperkalemia, hyperphosphatemia, hypocalcemia, met acidosis
Ucath materials that dec urethral reactivity & increase biofilm resistance
Plastic
Red rubber
Latex
Siliconized elastomer/teflon coated latex
hydrogel coated latex
pure silicone
in order of Most reactive –> least reactive
List of exogenous pyrogen
- Infectious agent (fungal, viral, rickettsial, bacteria, protozoal)
- Bacterial products (LPS, strepexotoxtin, staph enterotoxin, staph protein)
- Soluble antigen-aby complexes
- bile acids
- Drugs: bleomnycin, colchicine, tetracyclines, levamisole
- Tissue inflammation/necrosis
Thermoregulation
- Regulated by preoptic area of anterior hypothalamus
- Inflammation via microamines and cutaneous deep receptors
Heat gain mechanisms
- Increased production: catecholamines, thyroxine, shivering
- Decreased loss: vasoconstriction, piloerection, postural changes, seek warm environment
Hyperthermia classifications
- True fever: production endogenous pyrogens
- Inadequate heat dissipation: heat stroke or hyperpyrexic syndrome
- Exercise induced hyperthermia: normal exercise, hypocalcemic tetany, seizures
- Pathologic/pharm origin: lesions in or around anterior hypothalamus, malignant hyperthermia, hypermetabolic disorders, monoamine metabolism disturbances