Gas Exchange and Transport

Identify two mechanisms used to transport oxygen and three mechanisms used to transport carbon dioxide in the body
Determine whether there is sufficient oxygen delivery to the tissues using the arteriovenous difference or C(a-v)O2 calculation.

Normal cellular function and survival depend upon a continuous supply of oxygen. Inspired oxygen from the environment moves across the alveolar-capillary membrane into the blood and is then transported to the tissues. This delivery of oxygen sustains aerobic cellular metabolism throughout the body. Aerobic cellular metabolism is metabolism that takes place at the cellular level with the use of oxygen. This type of metabolism allows our cells to convert proteins, carbohydrates, and fats into adenosine triphosphate (ATP) also known as energy. This energy allows for normal body functions such as muscle movement, digestion, respiration, and circulation.

As oxygen and glucose are utilized by the mitochondria of the cell to produce ATP, one of the gases produced is carbon dioxide. Carbon dioxide is a byproduct of aerobic cellular metabolism and is of no use to the cells; therefore, it is excreted by the cells. Carbon dioxide (CO2) is removed from the body through the process of ventilation. Understanding oxygen and carbon dioxide transport help respiratory therapists identify problems that occur with certain pulmonary and airway emergencies.

Keeping in mind that ventilation is controlled by the hypothalamus of the brain, you are working the night shift at a local hospital and a 26-year-old victim of a motorcycle accident arrives in the emergency department. He sustained significant head trauma and it has been determined that he has increased intracranial pressures as a result. You notice he has irregular breathing. You obtain an ABG and report a PaCO2 of 55 and a pH of 7.25.

Respiratory therapists respond to these types of emergencies often. We must be able to recognize when our patients are deteriorating and when they are doing well. ABGs allow us to measure changes in status and help us determine our plan of action. The ABG you obtained reveals that our 26-year-old motorcycle victim is in respiratory failure and is unable to ventilate effectively, which means he is not breathing out enough CO2. The increase in CO2 has caused an imbalance in his acids and bases and therefore, a decrease in his pH has caused his blood to become more acidotic.

Prompt
Watch the video from Khan Academy before completing the assignment. This video will help you to understand how oxygen (O2) and carbon dioxide (CO2) is transported in the body.

Hemoglobin moves O2 and CO2
https://www.youtube.com/watch?v=QP8ImP6NCk (Links to an external site.)

In your own words, provide detailed responses to the following:
In detail, describe the two ways that oxygen is transported from the lungs to the tissues.
Describe the three ways that carbon dioxide is transported from the tissues to the lungs.
Explain the chemical reason most of the CO2 carried from the tissues to the lungs in the form of HCO3- through the RBC.
Explain what is arterial oxygen content (CaO2) and the clinical importance of the CaO2 value.
What basic information is provided by the venous oxygen content (CvO2)?
Provide the extensive information that is provided by the Arterial-venous Oxygen Content Difference (C(a-v)O2) value; how is it important in a clinical assessment? Give the full formula for the C(a-v)O2.
Describe the following:
Oxyhemoglobin
Carbaminohemoglobin

Requirements (read these carefully):
Submit your responses, in your own words, as an essay form, complete sentences, in at least 500 words on a Word document (excluding the prompt, title, cover page, citations/references, quotations). This is a formal written project, grammar, and spelling count. You must include at least two references (the course text being one of your references) to defend and support your position. APA is encouraged.