Shock, Heart Flashcards
Shock
Poor blood flow
Inadequate O2 perfusion to tissues
Hypovolemic shock
- Reduction of circulating blood volume
- dehydration
- bleeding
Distributive shock
- Poor blood flow due to vasodilation
- Pooling of blood in veins & capillaries
- Anaphylaxis
- Poision
- Venom
Cardiogenic shock
- decreased cardiac output
- Obstructive shock - obstruction of blood flow from heartworms or hypertension
- Heart failure
- heart disease
Septic shock
- opportunistic bacterial growth from poor perfusion
Cardiac output
CO=HR x SV
Cardiac output: amount of blood pumped in each ventricle per min
HR: Number of beats per min
SV: Volume of blood pumped in the ventricles per heart beat
Systemic Allergic reactions
Anaphylaxis
- Life threatening
- Hypersensitivity reaction
- Releases histamines causing vasodilation
- Lowers BP
- Venom
- Drugs
Uticaria
- Acute focal swelling and hives
- Foods
Angioneurotic edema
- swelling of tissues under skin
- foods
Drug allergies
- Hypersensitivy to drugs
- antibiotics
- vaccines
Dogs: target organ is the liver
- Vomit
- respiratory distress
Cats: target organ is GI & respiratory
- Vomit
- difficulty breathing
CHF
Congestive heart failure
Signs
- Tachycardia
- cardiomeagly (enlarged heart)
Left Ventricular Heart Failure
- dysfunction in mitral valve in Lt. Ventricle (or both)
- Coughing
- snycope
- pulmonary edema
Right Ventricular Heart Failure
- Dysfunction on tricspid valve on Rt. ventricle (or both)
- Hepatic enlargement
- ascites
- pleural effusion
- sub q edema
- congestion to systemic circulation
Congestive Heart Failure Types
Cardiomyopathy
- Infections
- genetic disorder
- degeneration
- ineffective contraction
- ineffective pumping
Hypertension
- Leads to thickening of Lt. Ventricle
- Leads to enlarged cardiac muscle
- Increase O2 demand
Vascular disease
- Overworks ventricles. Valves don’t close tightly
- Blood leaks back into ventricles
- Overloads muscle and stretches causing more O2 demand and energy
CHF Compensatory Response
Cardiac Failure > decreases output > poor perfusion (kidneys) > kidney activates renin-angiotension system > Increases BP & Cardiac output & increases aldosterone (vasoconstriction) > heart works harder > Heart continues to decline
Cardiac Failure > decreases output > heart stimulates baroreceptor > which activates sympathetic nervous system > increases BP, RR, CO, Aldosterone > Vasoconstriction - retains Na & H2O, excretes K > increases blood volume > heart works harder > heart function declines
Preload vs Afterload
Preload
Volume of blood entering Rt. side of heart
Right sided heart disease
Afterload
Force that pushes blood out of the Lt. Ventricle and into rest of body
Leftsided heart failure
Chamber Pressure
Lt Ventricle has highest pressure during systole to help eject blood
Rt. Atrium has lowest pressure
Congenital Heart disease
4 types
PDA (1/4)
PDA (Patent ductus ateriosus)
- lack of closure to the ductus arteriosus (Blood vessel that connects Aorta to pulmonary artery)
- Open in fetus to allow blood to bypass lungs. Closes at birth to inflate lungs. PDA, lack of closure
- Blood is shunted from aorta to pulmonary artery (vice versa) mixes O2 blood with non O2 blood. (left > right shunt)
- Volume overload in pulmonary arteries/veins.
- Dilation of left chambers
- Left sided heart failure
Signs
- Inactivity
- Shortness of breath
- collapse
- murmmer (can be heard w/o stethoscope)
- Abnormal growth (smaller)
Prognosis
- Left untreated will not survive over a year
Treatment
- Surgery, Ligate ductus Arteriosis
- Catheter based occlusion (coil)
- Meds to decrease BP
Congenital Heart disease
4 types
PS (2/4)
Pulmonic Stenosis
- narrowing of pulmonic valve opening (pulmonic semilunar valve)
- Abnormal formation of valve or valve thickening
- Rt. Ventricle becomes enlarged
- Rt. Sided heart failure
- small breeds
Signs
- Murmmer
- Edema
- weakness
- collapse
- intolerant to excersice
Treatment
- Remove the narrowing
- Improve blood flow
- balloon valvuloplasty (stretches narrowing)
Prognosis
- can live normal life span if not too severe
Congenital Heart disease
4 types
SAS (3/4)
Sub aortic Stenosis
- Narrowing of opening b/t aortic valve and Lt. ventricular. (Aortic semilunar valve)
- Left sided heart failure
- Enlargement of left ventricle due to overwork
- Common in large breeds
Signs
- weakness
- lethargy
- fainting
- Intolerant to excersice
- Poor growth
- Inadequate tissue profussion
Prognosis
- short life span from lt. sided heart failure
- normal life if mild
- has increase risk of aortic valve infection
Treatment
- Surgery
- Surgical opening of stenotic area of aorta
- Atenolol (beta blocker)
- Sotalol (Anti arrythmic/beta blocker)
Congenital Heart disease
4 types
VSD (4/4)
Ventricular Septal Defect
- Incomplete division of chambers
- Septal defect bt Rt & Lt ventricle.
- Tissue receives inadequate O2 blood
Signs
- Murmmer
- may not show signs
- decrease staminea
- poor growth
Treatment
- Surgery to correct defect
Congenital Heart disease
Diagnosis
- ECG
- Thoracic radiograph
- BP
- Blood work
- cardiac catheterization
- Angiogram
- doppler
Valvular Disease
AVVI
Atrioventricular valvular Insufficiency
- Regurigation of blood back into atria
- Common in CHF in dogs
Signs
- Murmmer
- Cough
- Intolerant to excerise
Hypertrophic Cardiomyopathies
Lesions in heart muscle
Primary (Cats)
Hypertrophic
Dilated
Restrictive Form
Thickening of Lt. Ventricle wall
Decreases space for blood
left sided heart failure
Secondary (Dogs)
Infections
metabolic disorder
endocrine issues
Infiltrative process
