Shock + HF Flashcards
Low CVP in shock?
Hypovolemic and distributive
High CVP in shock?
Cardiogenic and obstructive
Low PCWP in shock?
Hypovolemic, obstructive and distributive
High PCWP in shock?
Cardiogenic
Low cardiac index and SvO2 in……………………
Neurogenic shock due to impaired sympathetic reflexes
Low cardiac index (CO) in shock?
Hypovolemic, cardiogenic, obstructive
Why there is increase PCWP in cardiac tamponade?
due to external compression of the heart despite low left-sided preload
High CO in shock?
Distributive shock
Low SVR in shock?
Distributive
High SVR (afterload) in shock?
Hypovolemic, cardiogenic, obstructive
Low SvO2 in shock?
Hypovolemic, cardiogenic, obstructive
High SvO2 in shock?
Distributive (in neurogenic is low)
Right-sided preload is called ……….
Central venous pressure (CVP)
Left-sided preload/left ATRIAL pressure is called ………
Pulmonary capillary wedge pressure (PCWP).
Why PCWP is decreased in septic shock?
Due to decreased venous return
Venous dilation in sepsis is caused due to ……… (2)
Peripheral venous dilation –> pooling of blood in dilated veins
Increased vascular permeability (third-spacing)
SVR decreased in sepsis is due to ……….
Arteriolar vasodilation
How changes action of the heart in sepsis when sympathetic drive increases?
Increased HR and contractility –> increased CO
What causes compensatory increase in sympathetic drive in sepsis? (2)
Hypotension and inflammation from sepsis
Why CO is increased in sepsis despite low ventricular preload?
Due to compensatory activation of sympathetic NS
What 2 factors affect increase of CO in sepsis?
Decr. afterload and baroreceptor reflex-mediated increase in HR (tachycardia)
CO in early and late stage of sepsis?
Early - increased due to compensation of SNS and dec. afterload
Late - decreased due to tissue ischemia and accumulation of cytotoxic mediators
Low CO results in ………..
inadequate oxygen delivery to the organs –> end-organ damage
Why there is increased mixed venous oxygen saturation in sepsis?
Increased CO cause rapid blood transit through the peripheral capillaries and incomplete oxygen uptake by the tissue
In neurogenic shock primary disturbance is in ………………..
Peripheral vasodilation
Difference in response between septic and neurogenic shock?
In sepsis - there is increase in sympathetic response –> high HR and contractility
In neurogenic - nerve injury –> no sympathetic response –> no increase in HR and contractility –> low CO
Why increase of TPR is important in shock?
To maintain end-organ perfusion
How changes distribution of the blood in the body when there is shock?
Blood shunts from extremities and skin to vital organs
What causes increase of venous return?
Systemic venous constriction
What is kidney reaction to shock?
Increased RAAS –> increase of Na and water retention
Treatment of hypovolemic shock?
Blood transfusion and crystalloid infusion (saline)
What changes cause infusion of saline in shock? (2)
Increase intravascular and LV end-diastolic volume
Shock. Treatment = saline. How it changes heart work of fibers/SV/CO?
Incr. LV EDV –> stretch of myocardium and increased length of sarcomere at the end of diastole –> Frank Starling mechanism –> contraction –> increased SV and CO
With shock, poor organ and tissue perfusion leads to tissue …………… and increased …………….. metabolism
Tissue hypoxia –> increased anaerobic metabolism –> lactatic acidosis
Metabolic disturbance in shock?
Metabolic (lactatic) acidosis –> with compensatory respiratory alkalosis due to increased CO2 exhalation since there is reduction in pH
If hypovolemic shock is with diarrhea, how it worsens presented metabolic disturbance?
Loss of bicarbonate from GI tract worsens metabolic acidosis and increase a ventilation even more
Location of primary disturbance in cardiogenic shock?
Typically left ventricular failure
MI –> acute LV failure and cardiogenic shock. 3 symptoms?
Hypotension + pulmonary crackles + audible S3
Pulmonary embolism symptoms? (7)
Acute-onset chest pain + shortness of breath. Tachycardia Tachypnea JVD Clear lung May manifest syncope/near syncope
ABG in PE?
Hypoxemia + acute resp. alkalosis due to hyperventilation
PE. Changes in pulmonary artery and RV?
Increase in pressure.
Increase in pressure in RV in PE cause ……………. (change of RV?)
Dilation/RV cavity dilation - due to RV wall tension and cardiac muscle stretching.
How changes RV myocardial oxygen consumption and coronary artery perfusion in PE? It leads to ……….
O2 demand increases and coronary artery perfusion decreases.
Leads to supply/demand mismatch and RV ischemia
Why there is decreased coronary artery perfusion in PE?
decreased RV output due to obstruction –> decr. LV preload and CO –> decr. RV O2 supply (because myocardium gets oxygenated blood from left ventricle) –> RV ischemia
Incr. RV O2 demand and decr. coronary artery perfusion results in …………… –> …………………. (RV changes)
RV ischemia –> RV failure (cannot pump blood –> even more decreased left-side preload –> decr. CO)
In what pathologies manifest and doesn’t thickening of RV?
RV thickening manifest in chronic pulmonary hypertension.
There is no thickening of RV wall in acute PE, because it is not enough time.
LV CAVITY changes in acute PE?
LV is normal or somewhat reduced in size due to reduced blood flow from right heart.
LV WALL changes in acute PE?
Nothing. Thickening is expected not with PE, but with systemic hypertension or severe aortic stenosis
Pulmonary arterial hypertension in chronic respiratory diseases. 2 factors.
- Hypoxia induced pulmonary vasoconstriction
2. Associated vascular remodeling, therefore RV must work harder
Patient has pulmonary arterial hypertension thus is predisposed to RHF. What 2 conditions can lead to RHF?
- Subacutely from progressive pulmonary hypertension
2. Acutely due to PE (sudden obstruction of an already comprosmised pulmonary capillary bed)
Pulmonary arterial hypertension. CVP, RV size, PCWP and CO?
CVP increased;
RV size - increased due to volume overload;
PCWP - decreased
CO - decreased
Symptoms of decreased CO? (4)
Dyspnea
Fatigue
Exertional angina
Syncope
Right atrial pressure and LVEDP in RHF?
RAP - increased
LVEDP - normal/decreased due to impaired RV output - less blood in the left heart
Right atrial pressure and LVEDP in LHF?
RAP = normal/decreased
LVEDP - increased
When manifest RHF due to LHF?
In advanced stage
RV dysfunction results in the backup of blood within the venous circulation, leading to increased CVP, which is transmitted to …………
PORTAL CAPILLARIES (ie, hepatic sinusoids).
Hydrostatic pressure and oncotic pressure in ascitis?
Increased and normal.
When manifest hypoalbuminemia in RHF caused ascitis?
Albumin half time is ~21d, therefore hypoalbuminemia may manifest after several weeks, therefore in early disease oncotic pressure is normal
Hepatic sinusoid in ascitis. 2 characteristics.
Sinusoidal engorgement due to congestion, but permeability unaffected.
What pressures would resolve ascitis?
High oncotic and low hydrostatic pressure in portal capillaries
In what case can be increased portal capillary permeability?
In hepatic malignancies which disrupt portal capillary integrity
LVEDP and RAP in LHF?
LVEDP increased, RAP ir normal/decreased (in early disease)
RAP in late stage of LHF?
Invariably/always elevated
How chronic hypertension causes HF?
Concentric LV hypertrophy and resulting diastolic dysfunction
Acute pulmonary edema caused due to …………………………. pressure
increased alveolar capillary hydrostatic pressure
How looks alveoli in acute cardiogenic pulmonary edema?
Engorged alveolar capillaries (storos raudonos lyg susisukusios kraujagysles)
What material is in alveoli in acute cardiogenic pulmonary edema?
Pink, acellular material - results from transudation of fluid plasma
When RBCs leak to the alveoli?
RBCs leak to the alveoli in chronic pulmonary congestion, when too high pressure breaks vessels
histopathology of acute and chronic pulmonary congestion.
Acute: engorged alveolar capillaries with pink, acellular material within alveoli
Chronic - RBCs extravasate into alveoli –> hemosiderin-laden macrophages
How is formed hemosiderin in chronic HF?
RBCs phagocytosed by macrophages –> iron from heme is converted to hemosiderin
What iron stores can detect Prussian blue stain?
Ferritin and hemosiderin
Where can be founded siderophages and identified by Prussian blue stain?
In any tissue where macrophages encounter extravasated RBCs
In which vessel increased pressure cause pulmonary edema when HF?
ELEVATED PULMONARY VENOUS PRESSURE