Systems Review Flashcards
How much blood does the heart pump out every minute?
About 5 quarts (4.7L)
3 functions of the heart:
- Pump blood through the lungs removes CO2 and refreshes blood with oxygen
- Oxygenated blood is pumped to the body to provide oxygen and nutrients and to remove waste products
- Coronary arteries are blood vessels that supply blood and oxygen to the heart
Is heart a single or double pump?
Double
Narrowing of coronary arteries that prevent adequate blood supply to the heart. Caused by atherosclerosis, it may progress to the point where heart muscle is damaged due to lack of blood supply and oxygen (infarction, arrhythmias, heart failure)
Coronary artery disease
Males or females have higher cause of death from CVD?
Females
3 complications of atherosclerosis:
- Narrowing of arterial lumen
- Plaque fissure
- Thrombus formation
Causes of CAD? (5)
High blood cholesterol High BP Smoking Obesity Lack of PA
How many cardiac arrest in the OR occur per year?
> 17,000
S/S of CAD
None
Chest pain
Heart attack
Shortness of breath
5 minor clinical predictors
- advanced age
- abnormal DCG
- rhythm other than sinus
- history of CVA
- uncontrolled HTN
5 intermediate clinical predictors
- remote MI (>1month)
- stable angina
- compensated CHF
- creatinine 2
- diabetes
5 high clinical predictors
- acute or recent MI (<1month)
- unstable or severe angina
- large ischemic burden (+stress test)
- decompensated CHF
- significant arrhythmias
What does STEMI stand for?
ST elevation myocardial ischemia
What is STEMI?
Abrupt occlusion/decrease in coronary perfusion
- inflammatory process
- mortality rate 15-20%
3 period MI mechanisms
- Unstable plaque
- Catecholamines
- BP swings
Low surgery risk: (4) <1%
Endoscopic
Breast
Skin
Cataracts
Intermediate surgery risk: (4) 1-5%
Intraperitoneal/intrathoracic
Orthopedic
Head and neck
Carotid endarterectomy
High surgery risk: (3) >5%
Emergent
Aortic
Peripheral vascular
Treatments for CAD: (4)
Lifestyle changes
Medications
Angioplasty
Surgery
How to beta blockers work?
Reduce myocardial oxygen consumption by decreasing HR, contractility, and BP
How does Ca+ channel blockers work?
Dilate arteries-decrease SVR which decreases workload and O2 consumption
Decrease HR and myocardial contractility
Antiplatelets
Prevent platelet aggregation on atheroma or thrombus
How do you monitor heparin?
Partial thromboplastin time (PTT)
What do statins do?
Lower cholesterol; decrease LDL
What do ACE inhibitors do?
Treat HTN, and lower risk of recurrent MI
Oxygen therapy through nasal cannula
2L/min
Balloon is inflated, compressing the plaque against the artery wall and then balloon catheter is deflated and removed
Angioplasty
Blood vessel removed from leg, arm, chest to create new blood flow path in heart
Bypass surgery
Average SV
60-100ml
Average CO
3-9liters/min
Vasodynamic parameter
- relates CO to body surface area (BSA)
- heart performance to the size of individual
Cardiac index (CI)
Normal CI
2.1-4.9 L/min/m2
Right atrial, central venous pressure
3-12
Right ventricular pressure systolic and diastolic
15-30
3-8
Pulmonary artery pressure systolic and diastolic
15-30
4-12
Pulmonary vein/capillary wedge pressure
2-15
Left ventricular pressure systolic and diastolic
100-140
3-12
Pressure of blood in thoracic vena cava, near the right atrium
-reflects amount of blood returning to the heart and ability of heart to pump the blood into the arterial system
Central venous pressure (CVP)
What is good estimation for CVP
Right atrial pressure, which is major determinant of R ventricular end diastolic volume
Factors that decrease CVP:
Hypovolemia
Deep inhalation
Distributive shock
Hypervolemia Forced exhale Tension pneumothorax Heart failure Pleural effusion Decrease CO Cardiac tamponade Mechanical ventilation and PEEP
Factors that Increase CVP
3 things to avoid in valvular insufficiency:
Cardiac depression
Hypoxemia, hypercarbia, and acidosis bc they increase SVR
Over sedation preop
What is the most common type of heart defect?
Ventricular septal defect (VSD)
Septum between the two ventricles does not fully develop, leaving a hole
-blood flows from L to R ventricle and into lungs
Ventricular septal defect (VSD)
Slow, shallow breathing
CO2 buildup in blood (acidosis)
Hypoventilation
Rapid, deep breathing
CO2 blown off (alkalosis)
Hyperventilation
Primary muscles of respiration
Diaphragm
External intercostal muscles
Accessory muscles
Amount of air remaining in lungs at end of normal exhale
Function residual capacity (FRC)
Measures lung function, specifically the amount and/or speed of air that can be inhaled and exhaled
Spirometry
4 most common measured in spirometry?
- Forced vital capacity
- Forced expiratory volume at timed intervals (FEV1)
- Forced expiratory flow
- Maximal voluntary ventilation
Volume of air that can forcibly be blown out after full inspiration (L)
FVC
Volume of air that can forcibly be blown out in 1sec, after full inspiration
FEV1
Flow of air coming out of lung during the middle portion of forced expiration
Forced expiratory flow (FEF)
Mild severity of COPD
> 80 FEV1
Moderate severity of COPD
50-79 FEV1
Severe severity of COPD
30-49 FEV1
Very severe severity COPD
<30 FEV1
Renal auto-regulate at what MAPs
50-150mmHg
Is urine output auto regulated?
No but is linearly related to MAP >50mmHg
What are renal protective drugs?
Dopamine
Fenoldopam
How does dopamine help renal?
Increase renal blood flow
How does fenoldopam help renal?
AntiHTN, arterial/arteriolar vasodilation
What 2 are most problematic antimicrobials?
Aminoglycosides
Amphotericin B
What are the 3 nephrotoxins?
Antimicrobials
Contrast
NSAIDs
What drugs are affected by kidney function (6)
Propofol
Morphine and hydromorphone
Midazolam
Vecuronium and rocuronium
Which of the drugs that affect kidney function, is though tot have the least amount of renal excretion?
Vecuronium
2 surgical consideration with renal?
Increased intra-abdominal pressure during laparoscopy
Aortic cross clamping
Most common cause of death in pts with end stage renal failure?
Cardiovascular disease
Percent of blood flow through portal vein?
70%
Percent of blood flow through hepatic artery?
30%
Percent of blood flow of CO?
25%
Does liver maintain auto regulation of blood flow with cirrhosis and exposure to volatile anesthetics?
NO