Cont Flashcards
Describe volatile acids
Can be excreted by respiration
Ex. CO2
Describe fixed acids
Cant be excreted by respiration
Ex. Lactic acid
Describe the normal arterial blood pH
-Slightly basic because the slight H+ deficit leaves room to neutralize the biproducts od metabolic reaction
What is more common, acidosis or alkalosis?
Acidosis
Describe respiratory acidosis
- When you retain CO2 (volatile acid)
- Happens when you are not able to ventilate
Describe respiratory alkalosis
- Hyperventilation (decreased CO2 in the blood)
- Treatment is to regulate breathing (paper bag)
Describe metabolic acidosis
- Most common
- low pH
- Increased acidity in blood due to fixed acids
- pH less than 7.5
Examples of metabolic acidosis
- Diabetic ketoacidosis
- Lactic acidosis
- Shock patients
Describe metabolic alkalosis
- Not common
- Severe vomiting
- Antacids
- Body depresses respiration cause you want to retain CO2
Describe the buffer system
- First defense against excess acid
- Quickly acts to restrain a change in pH
How is hemoglobin buffered
Hydrogen in blood cells
How are most body cells buffered?
Cellular proteins
What is the equation for bicarbonate
H + HCO3 -> H2CO3 -> CO2 + H2O
What organ secretes the majority of acids
The kidney
What generates new bicarbonate molecules to replenish the stock?
Kidney
What gets rid of excess CO2
Lungs
Active process associated with inflammation or increased metabolic activity
Hyperemia
Characteristics of hyperemia
- Physiological response
- Due to increased functional demand
- Can be due to hormonal influence
Examples of hyperemia
- Hot flashes
- Fever
- Sunburn
Passive hyperemia process associated with impaired venous flow due to hydrostatic forces
Congestion
What sort of blood is characteristic of congestion?
Poorly oxygenated dark blood
What causes pulmonary congestion?
- Heart failure
- Ascites (from the hepatic portal veins)
What is an example of local congestion
Venous obstruction of a limb
Where is chronic passive congestion common?
-In the liver due to right heart failure
This is the activity of the blood vessel endothelium, platelets, and plasma coagulation
Hemostasis
What are the goals of hemostasis
- Keep blood in a fluid clot free state
- Form a clot to stop the bleeding at the site of vascular injury
- Balance pro and anticlotting forces
What is the normal hemostatic reaction?
- Vascular disruption
- Temporary constrict blood vessels and vasodilate
- Blood gets exposed to tissue factors and causes platelets to become sticky
- Platelets adhere to the edges of the wound and become a thrombotic plug
- Blood that is exposed to the tissues help form a permanent plug
What is the first element of the coagulation process?
Endothelial Cells
What do endothelial cells have that help maintain balance of the pro and anticlotting forces
-Antithrombotic and anticoagulant activity
What is the 2nd element of the coagulation process?
Platelets
Where do platelets originate from?
Megakaryocytes
What are the 2 main functions of platelets?
- Form the thrombotic plug and attract more platelets
- Initiate the clotting cascade
What is the 3rd element of the coagulation cascade?
Coagulation
When does coagulation start?
-When plasma or platelets come in contact with something unfamiliar
What does coagulation cause?
-Fibrinogen (Factor 1) to become fibrin and form a gel like substance that plugs the hole
What are the 2 pathways of the coagulation cascade?
- Extrinsic Coagulation Pathway
- Intrinsic Coagulation Pathway
Describe the extrinsic pathway
Starts when the coagulation factor 2 comes in contact with tissue factor in extravascular tissue
-Operates in clinical circumstances
Describe the intrinsic pathway
- Initiated when factor 7 comes in contact with a foreign surface
- Ex. When blood comes in contact with lab wear
What pathway(s) are activated during hemostasis?
Both extrinsic and intrinsic
This is the escape of blood from a blood vessel
Hemorrhage
This is the smallest hemorrhage
-Usually associated with platelet disorders
Petechiae
This is a hemorrhage less than 1 cm
Purpura
This is a hemorrhage greater than 1 cm
Ecchymosis
This is a large localized collection of blood
Hematuria
What commonly causes problems with coagulation factors?
The liver- because the liver makes coagulation factors
What are other coagulation problems due to genetics
Hemophilia- Factor 7 deficiency
What is the most common cause of coagulation factor deficiency?
Cirrhosis
What is usually associated with cirrhosis?
- Severe scarring
- Usually have bleeding problems due to underproduction of hepatic coagulation factors
What is essential for the production of Factors 7, 9, 10
Vitamin K deficiency
-This helps bond platelets
Von Willebrand Disease
Where is von willebrand facto made?
-Made in the endothelial cells and megakaryocytes
What are characteristics of Von Willebrands disease
- Spontaneous bleeding of the mouth, nose, and mucus membranes
- Lack of vWF interferers with platelet adhesion to the endothelium
Characteristics of hemophilia
- Factor 8 deficiency
- X-linked gene deficiency
- Can be mild to severe
Do people with hemophilia have a normal bleeding time and platelet count and a normal prothrombin time?
Yes
This assess the coagulation process
-The time it takes to clot after the addition of tissue factor
Prothrombin time
This is the time it takes the clot after the addition of the artificial surface
Partial Thromboplastin time
This measures platelet numbers only
-Does not determine if platelets function properly
Platelet count
This detects defective platelet function
Platelet function analysis
The time required for a patient to stop bleeding after a skin prick
Bleeding time
This is a collection of cellular elements of blood that only forms under pathologic conditions
Thrombosis
Is a thrombus formed fast or slow?
Slowly
When is a thrombosis formed?
When platelets and WBC adhere to the endothelium
What are 3 components that lead to thrombus formation?
- Endothelial injury
- Abnormal Local blood flow
- Hypercoagulability
What can happen if a thrombus gets too big
-It can occlude blood flow and cause death of downstream tissue
This is when clotting forms without exposure to tissue
Disseminated Intravascular coagulation
What does DIC lead to?
- Clots
- Hemorrhages
T/F- DIC is Always secondary to another underlying condition
True
What are examples of underlying conditions that cause DIC
- Sepsis
- Bacterial infections
Is DIC fatal?
Usually
What initially happens in DIC?
The body starts spontaneously clotting
-uses all the platelet and coagulation factors
This is an intravascular object that travels in the blood stream from one place to another
Embolism
What are examples of sources of emboli?
- Pulmonary
- Systemic
- Marrow Fat
- Air
- Amniotic fluid
These are fragments made in the deep veins and carried into the lungs
-Produce instant death
Pulmonary Thrombi
These cling to the inner wall of a damaged heart muscle
-Travel to the lower extremity and the brain
Systemic thrombi
This is common after a fracture or CPR
Marrow fat
This is air bubbles in the arteriole tree
Air
This fluid enters the maternal circulation
-Fetal debris lodges in the small vessels of the lungs
Amniotic fluid
This is an area of ischemic necrosis
Infarct
What are 2 types of infarcts
- Red Infarct
- White infarcts
- When arteriole occusion occurs in dense solid tissue
- Seen in kidney, heart, and liver
White infarcts
This is a venous or arteriole obstruction that occurs in loose spongy tissue
- Seen in the lungs and liver
- Have a dual blood supply
Red Infarcts
Circulatory collapse=
Shock
Describe shock
-A state of systemically low blood flow when cardiac output is reduced or effective blood volume is decreased
What are the 4 types of shock?
- Hypovolumic shock
- Cardiogenic shock
- Obstructive Shock
- Septic Shock
Describe hypovolemic shock
- Decrease blood volume (some trauma event)
- Pressure drops
- Shock like status because you cant keep up cardiac output
- Fluid loss (diarrhea, burns, lose hydration through the skin)
This causes swelling and fluid movement from intracellular to extracellular
- Cant maintain normal blood flow
- Loss of fluid from the vascular compartment
Anaphases
Describe cardiogenic shock
• Lose pumping power and cant maintain cardiac output
What is a cause of cardiogenic shock?
- MI
- Heart and muscle disease
Describe septic shock
- Seen a lot
- Caused or induced by infections- causes inflammatory response
- Can cause cardiogenic or hypovolemic shock
- DIC (deseminated intracellular coagulation)
- Decreases bp and results in hypoperfusion
What does your body do to compensate in septic shock?
o Increase HR o Vasoconstriction (by angiotensin) to increase PVR o Body is going to try to retain fluids (via ADH and aldosterone)
Describe obstructive shock
- Seen in paracardial tamponade- trauma patients
- Obstructive force causes mechanical interference
- Leads into cardiogenic- heart loses the ability to pump
What are the 3 stages of shock
- Non-progressive
- Progressive
- Irreversible Shock
Describe non-progressive shock
- Re-establish profusion
- But your low BP continues
- Hypoxia occurs (bc RBC cant deliver blood)
- Anaerobic metabolism starts- lactic acid is produced as a byproduct
- Lactic acid is a fixed acid (causes pH to go down)
- Body wants to increase pH via bicarb from the kidney, and increase ventilation (get rid of CO2 which is a volatile acid)
Describe non-progressive shock
- More severe hyperperfsion
- More acidtic
- More hypoperfused
- More septic- in your gut
- Not all progressive shock leads into DIC
- You can get to a point where nothing is reversible
Describe irreversible shock
- Heart- starving for o2 and decreases contractility
- Decrease filtration/dehydration
- Once your kidneys fail you cant maintain and allow for reabsorption and cant secrete bicarb
- Kidney and heart
