Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Pulmonary circ
Pulmonary circulation- 1/14/2013- CJ
| Question | Answer |
|---|---|
| Pulmonary circulation is used to | Transport deoxygenated hypercarbic blood to the lungs and to transport oxygenated blood to the left ventricle |
| The pulmonary circulation receive what percent of cardiac output | 100%! (5L/min) |
| Flow of blood leaving heart into pulmonary circulation | Pulmonary artery- Branch with airways- Mesh of capillaries at respiratory bronchioles- Pulmonary venules- Pulmonary veins |
| Pulmonary circulation flow is (high/low) | High |
| Pulmonary circulation pressure is (high/low) | Low |
| Normal pulmonary flow value | 5 L/min |
| Normal pulmonary pressure value | 15 mmHg |
| Walls of the pulmonary arteries contain little smooth muscle because | They do not need to redirect blood, only distribute it to produce a thin film |
| The work required by the right ventricle is | Low |
| Pulmonary capillaries are exposed to alveolar pressure which can cause capillaries to be __ or__ | Distended or compressed |
| When the alveolar pressure is greater than the internal capillary pressure, the capillary is | Compressed |
| When alveolar pressure is less than internal capillary pressure, the capillary is | Distended |
| Inspiration does what to the pulmonary arteries and veins (extra-alveolar vessels) | Pulls them open ("Radial traction") |
| Extra-alveolar vessel diameter is determined by | Lung volume |
| Define Caliber | Diameter of vessel |
| Alveolar vessel caliber is determined by | Balance between internal and alveolar pressures |
| Pulmonary resistance is calculated as | 1/10th of the systemic vascular resistance |
| Pulmonary resistance equation | (Pressure in pulmonary artery-Pressure in left atrium)/ Flow |
| Pulmonary vascular resistance decreases with and increase in | Arterial or venous pressure |
| An increase in cardiac output does what to Pulmonary arterial pressure | Increases |
| An increase in cardiac output does what to pulmonary vascular resistance? | Decreases |
| An increase in pulmonary pressure does what do pulmonary vascular resistance | Decreases **THIS IS AN EXCEPTION TO OHMS LAW*** |
| If cardiac output decreases, pulmonary pressure decreases and pulmonary resistance ___ | Increases |
| What is the explanation for reduced pulmonary vascular resistance with an increase in pulmonary pressure? | Recruitment and distention of capillaries |
| Explain the concept of "recruitment and distension" | Normally, not all capillaries are open and conductive to blood. When the Pulmonary pressure increases, capillaries become distended and more capillaries are recruited for use |
| Extra-aveolar vessles include | Pulmonary veins and arteries |
| Pulmonary vascular resistance increases at _____ lung volumes | Low and high |
| What causes high resistance at residual volume | At RV, there is no compression of pulmonary capillaries by alveolar pressure but little radial traction and smooth muscle/elastin in extra-alveolar vessels keeps caliber low so the resistance is high |
| What causes high resistance at total lung capacity | Extra-alveolar vessels are stretched open by traction but pulmonary capillaries are narrowed by alveolar pressure so the resistance is high |
| Explain why pulmonary vascular resistance is lowest at functional residual capacity? (when lungs are "medium") | Radial traction to open extra-alveolar vessels is present but not enough to compress the pulmonary capillaries |
| Pulmonary blood from is the greatest at the | Lung base |
| The difference in pulmonary blood from from top to bottom is due to | Gravity and hydrostatic pressure |
| The pulmonary arterior pressure is greatest at the | Base of the lung |
| Blood flow increases from __ to ___ | Apex to base |
| Hydrostatic pressure in the apex of the lung causes capillaries to be | Compressed |
| Hydrostatic pressure in the base of the lung causes capillaries to be | Distended |
| Pulmonary vasoconstriction occurs in | Hypoxia |
| As the Po2 decreases, blood flow __ because of hypoxic pulmonary vasoconstriction | Decreases |
| ___ channels in the smooth muscle close and cause depolarization and in increase in vascular tone | Oxygen sensitive potassium channels |
| After Potassium channels close, depolarization causes ___ channels to open which increase tone and decrease blood flow | Calcium |
| Hypoxic vasoconstriction directs blood away from | Under-ventilated areas |
| When can hypoxic vasoconstriction be dangerous? | When the whole lung is hypoxic |
| Explain what happens when the whole lung becomes hypoxic | Vasoconstriction occurs in all of the pulmonary vessels which causes blood to back up into the pulmonary arteries. This causes hypertension which leads to pulmonary edema and eventually to right side heart failure |
| Name two situations that would make hypoxic vasoconstriction dangerous | COPD and high altitude |
| Water in the alveoli does what to surface tension | Increases |
| Water in the alveoli does what to compliance | Decreases |
| Water in the aveoli does what for the diffusion pathway for oxygen? | Increases |
| Which forces act to keep water IN the capillaries? | Net colloid osmotic pressure and alveolar pressure |
| Which forces act to push water OUT of the capillaries? | Net hydrostatic pressure and surface tension (which is an attractive force between water molecules and the capillary walls) |
| Fluids that leak out of capillaries enter the intersitum and drain through the | Lymph channels in the perivascular space |
| If lymphatics are engorged or blocked, fluid enters the | Alveoli and creates edema |
| Early edema is due to | The engorgement of the interstitial space |
| Late edema is due to | Fluid in the alveoli |
| Causes of pulmonary hypertension | Increased left atrial pressure, increased pulmonary blood flow, and increased pulmonary vascular resistance |
| Changes in starling forcecs or pulmonary capillary permeability can cause | Interstitial and alveolar edema in the lungs |
| A blood clot in the lungs will do what to Dead space and overall pulmonary resistance? | Increase both |
Created by:
mcasto
Popular Medical sets