Cardiorespiratory System Flashcards
Cardiorespiratory System
Cardiovascular & Respiratory System responsible for perfusion, nutrition, and waste removal (co2) from cells.
Mediastinum
The space in the thoracic cavity that contains all the internal organs of the chest (heart, esophagus, thymus,etc) EXCEPT for lungs.
Cardiac muscle
One of the 3 types of muscle tissue (skeletal & smooth) that is similar to skeletal muscle, in that it contains myofibrils & sarcomeres giving it a striated appearance, but is involuntary with shorter and tighter sarcomeres.
Heart Structure: Number of chambers
Four total. Right side Atrium & Ventricle, and Left side Atrium & Ventricle.
Heart Structure: Right side
Known as the Pulmonic Side. It receives deoxygenated blood from the body and sends it into the lungs, where it is freed of co2 waste & re-oxygenated. Diagramed in blue.
Heart Structure: Left side
Known as the Systemic side, because it receives oxygenated blood from the lungs and delivers it to the rest of the body. Diagramed in red.
Atrium
Superior chamber that gathers blood returning to the heart. Smaller than ventricles.
Ventricle
Inferior chamber that pumps blood to lungs (right side ventricle) or body (left side ventricle).
Right Ventricle characteristics
Thin walled and pumps under low pressure b/c it only has to pump a short distance to the lungs.
Right Ventricle function
Receives deoxygenated blood from the Right Atrium, supplied by the Superior & Inferior Vena Cava, and pumps through the left & right Pulmonary Arteries to the lungs.
Left Atrium function
Receives oxygenated blood from the lungs via the Right & Left Pulmonary Veins.
Right Atrium function
Receives deoxygenated blood from the Inferior & Superior Vena Cava.
Left Ventricle function
Pumps oxygenated blood through the body via the Aorta.
Heart Diagram and Circulation
Sketch it
Cardiac muscle: Intercalated Discs
Helps to hold cardiac muscle cells together during contraction & creates an electrical connection between the cells, allowing the heart to contract as one functional unit. Seen ad dark bands that are irregularly spaced.
RHR normal limits
60 to 100
SA sinoatrial node
Located in the Right Atrium, this node initiates an electrical signal that causes the heart to beat. The signal runs down through both atria & ventricles. Known as the pacemaker of the heart.
AV atrioventricular node
Located inferior to the SA node at the bottom of the Right Atrium, it is responsible to delay the impulse sent by the SA node from reaching the ventricles, so that the ventricles have time to adequately fill with blood before contracting and thus pumping to lungs & body.
Heart Electrical Conduction System: Flowchart and Sketch
Include:
SA node
AV node
Right bundle branch
Left bundle branch
Heart stroke volume
The amount of blood pumped out of the heart w/ each contraction. The difference between the ventricular End-Diastolic Volume (the filled up ventricle before contraction) & the End-Systolic Volume ( the blood remaining in the ventricle after ejection).
Typical Stroke volume in mL
It is 70 mL.
End-diastolic = 120 mL (blood filled vent)
End-systolic = 50 mL (residual)
So, 70 mL of blood was pumped thru body
Cardiac Output (Q)
The volume of blood pumped thru the body per minute. (mL blood/min). It is calculated by heart rate (x) stroke volume.
Cardiac output at rest is about 5 L/ min and may go as high ad 30 L/min under vigorous exercise.
Measure HR during exercise
Take pulse for 6 seconds. Add a zero to the number of pulses felt.
Ex. 17 pulses in 6 seconds = 170 bpm.
Blood: composition
Blood is made of three cells: RBC, WBC, and Platelets (45% of blood content)
Platelets help w/ clotting and contain growth factors that heal injuries.
Blood cells are suspended in plasma (55% of blood content) which contains nutrients like glucose, lipids, proteins, and also hormones.
Blood volume in average adult
4 to 6 L
Blood: The 3 Support Mechanisims
Transportation: Nutrients in and waste products out. Drives hormones, GF and stem cells to organs & tissues. Carries heat thru body.
Regulation: Regulates body temp and acid balance.
Protection: Clotting & infection fighting
Stem Cells
Cells that divide & develop into specialized cells, such as brain cells, blood cells, heart cells & bone cells.
Capillaries
The smallest vessels, where arterioles & venules meet & nutrient exchange takes place.
Frank-Starling Law
Stroke volume increases when there is:
Increased venous return
Increased ventricle filling
Because increased ventricular filling improves contractile force as a result of the greater stretch of the muscle fibers of the heart.
Takeaway: Exercise improves stroke volume. Maintain equality between right & left sides of heart.
Blood Pressure composition
Cardiac output & Peripheral resistance (the amt of resistance in the arteries that must be overcome for blood to flow)
Respiratory System
Includes the lungs, airway & respiratory muscles that draw oxygen into the lungs, where oxygen and co2 are exchanged.
Inspiratory Ventilation
An Active process, that requires the contraction of inspiratory muscles to increase thoracic cavity volume, which decreases intrapulmonary pressure (air pressure w/i the thoracic cavity).
When intrapulmonary pressure drops below that of the atmosphere, air is drawn into the lungs.
Structures of the Respiratory Pump: Bones
Sternum
Rib cage
Vertebrae
Structures of the Respiratory Pump: Inspiration Muscles
Diaphragm
EXTERNAL Intercostals
Scalenes (side of neck)
Sternocleidomastoid (front of neck)
Pectoralis Minor
Structures of the Respiratory Pump: Expiration Muscles
Internal intercostals
Abdominals
Primary vs. Secondary Inspiratory muscles
Primary: Normal breathing
Diaphragm
External intercostals
Secondary: Heavy breathing
Scalenes
sternocleidomastoid
Pectoralis minor
Adult Respiratory Rate WNL
12 to 16 per min.
Characteristics of Passive Expiratory Ventilation
The RELAXATION of contracting respiratory muscles (ie- the diaphragm rises)
Characteristics of Active Expiratory Ventilation
An active process b/c expiratory muscles need to CONTRACT & compress the thoracic cavity to force air out.
Relationship between inspiration and circulation
During inhalation, inter-thoracic pressure is lowered, causing a drop in the pressure to the right atrium, helping to improve circulation back to the heart.
Conducting Airways vs. Respiratory Airways
Conducting: purify, humidify, warm/cool
Nasal cavity
Oral cavity
Pharynx
Larynx
Trachea
R&L Pulmonary bronchi
Bronchioles
Respiratory Airways: Diffusion happens here (o2 & co2 exchange)
Alveoli
Alveolar sacs
Fundamental rule of Fat Loss
Fat cannot be burned (used for energy) w/o the presence of o2. Body mass can only be non-surgically removed from the body through the exhalation of co2.
Tachypnea vs Bradypnea
Tachy: over 24
Brady: under 8
