Cardiopulmonary Physiology & Pathophysiology Flashcards

What is the primary function of the alveoli in the lungs?

Answer: Gas exchange with capillaries

The alveoli are tiny air sacs in the lungs surrounded by a network of capillaries. Their primary function is to facilitate the vital process of gas exchange, where oxygen from inhaled air diffuses into the blood, and carbon dioxide from the blood diffuses into the alveoli to be exhaled. This efficient exchange is critical for oxygenating the body and removing metabolic waste CO2.

What causes hypoxemia?

Answer: Low oxygen levels in arterial blood

Hypoxemia is defined as an abnormally low concentration of oxygen in the arterial blood. This condition indicates that the body is not receiving sufficient oxygen, which can impair organ function and lead to various health complications. It is often diagnosed through arterial blood gas analysis or by monitoring oxygen saturation levels.

What is the function of the right ventricle?

Answer: Pumps blood to the lungs

The right ventricle is one of the four chambers of the heart, specifically responsible for pumping deoxygenated blood. It receives blood from the right atrium and then forcefully contracts to push this blood into the pulmonary artery, which carries it to the lungs for oxygenation. This is a crucial step in the pulmonary circulation, preparing blood for systemic distribution.

What is respiratory acidosis?

Answer: Carbon dioxide retention causing low pH

Respiratory acidosis occurs when the lungs cannot remove enough carbon dioxide (CO2) from the body, leading to an accumulation of CO2 in the blood. This excess CO2 forms carbonic acid, which lowers the blood's pH, making it more acidic. It is often caused by hypoventilation or impaired respiratory function, such as in conditions like COPD or opioid overdose.

What is the role of hemoglobin in oxygen transport?

Answer: Binds and transports oxygen

Hemoglobin is a protein found in red blood cells that contains iron. Its primary and vital role is to bind reversibly with oxygen in the lungs, forming oxyhemoglobin, and then transport this oxygen efficiently to tissues and organs throughout the body. It also plays a role in transporting carbon dioxide back to the lungs for exhalation.

Which condition is characterized by chronic airflow limitation?

Answer: COPD

COPD, or Chronic Obstructive Pulmonary Disease, is a progressive lung disease characterized by persistent airflow limitation. This limitation is typically caused by inflammation and damage to the airways and air sacs (alveoli) in the lungs, making it difficult to breathe. Common symptoms include shortness of breath, coughing, and wheezing, often exacerbated by smoking.

What is the main function of the pulmonary artery?

Answer: Carries deoxygenated blood to lungs

The pulmonary artery is unique among arteries because it carries deoxygenated blood. It originates from the right ventricle of the heart and branches into smaller arteries that deliver this oxygen-poor blood to the capillaries surrounding the alveoli in the lungs. Here, gas exchange occurs, and the blood becomes oxygenated before returning to the heart.

What is a hallmark symptom of pulmonary embolism?

Answer: Sudden shortness of breath

A pulmonary embolism (PE) occurs when a blood clot travels to the lungs and blocks one or more pulmonary arteries. The most common and often sudden symptom of a PE is dyspnea, or shortness of breath, which can be accompanied by chest pain, coughing, and rapid heart rate. This sudden onset of breathing difficulty is due to impaired gas exchange in the affected lung areas.

How is oxygen saturation typically measured?

Answer: Pulse oximetry

Oxygen saturation is typically measured non-invasively using a pulse oximeter. This device clips onto a finger or earlobe and uses light absorption to estimate the percentage of hemoglobin in the blood that is saturated with oxygen. Pulse oximetry provides a quick, continuous, and convenient assessment of a patient's oxygenation status.