Question

ANSWER ALL 11 QUESTIONS PLEASE

DON'T !!! ANSWER IF YOU DON'T KNOW ALL THE ANSWERS THANK YOU.

1. What things affect airflow and which one is the most important?

2. Explain how an asthma attack could create a life-threatening condition?

3. Explain how emphysema is associated with expiratory flow limitation and its consequence on the person’s health

4. What are the muscles of inspiration?

5. What role do these muscles perform?

6. What are the primary sources of resistance for inhalation?

7. How would pulmonary edema (accumulation of fluid in lung tissue) affect lung compliance?

8. How would pulmonary edema affect motor unit recruitment to the inspiratory muscles?

9. How does breath-holding affect PO2 and PCO2 in the alveoli?

10. Do the tissues of your body stop their metabolism (i.e., O2 consumption and CO2 production) when you hold your breath?

11. Predict what would happen to PO2 and PCO2 in the systemic arterial blood if you held your breath for a long time.

Answer 1

1. Factors affecting the air flow :

These factors include properties of atmospheric air (density, pressure, temperature etc as found in various levels as defined by ISA conditions),

2. Asthma attack an life threatening condition :

Asthma signs and symptoms include:

Shortness of breath

Chest tightness or pain

Wheezing when exhaling, which is a common sign of asthma in children

Trouble sleeping caused by shortness of breath, coughing or wheezing

Coughing or wheezing attacks that are worsened by a respiratory virus, such as a cold or the flu

Signs that your asthma is probably worsening include:

Asthma signs and symptoms that are more frequent and bothersome

Increasing difficulty breathing, as measuredwith a device used to check how well your lungs are working (peak flow meter)The need to use a quick-relief inhaler more

Severe asthma attacks can be life-threatening. Work with your doctor to determine what to do when your signs and symptoms worsen — and when you need emergency treatment. Signs of an asthma emergency include:

Rapid worsening of shortness of breath or wheezing

No improvement even after using a quick-relief inhaler

Shortness of breath when you are doing minimal physical activity

3. Emphysema affecting the EFL

  Expiratory flow limitation (EFL) is the pathophysiological hallmark of chronic obstructive pulmonary disease (COPD) and arises because of the dual effects of permanent parenchymal destruction (emphysema) and airway dysfunction, which in turn reflect the effects of small airway inflammation (mucosal oedema, airway remodelling and mucous impaction) and possibly increased cholinergic airway smooth muscle tone .

Emphysema results in reduced lung elastic recoil pressure, which leads to a reduced driving pressure for expiratory flow through narrowed and poorly supported airways in which airflow resistance is significantly increased. EFL is said to be present “when the expiratory flows generated during spontaneous tidal breathing represent the maximal possible flow rates that can be generated at that operating lung volume” . Under conditions of EFL, expiratory flow rates are independent of expiratory muscle effort and are determined by the static lung recoil pressure and the resistance of the airways upstream from the flow-limiting segment .

4. Muscles of inspiration :

  The primary muscles of inspiration are the diaphragm, the upper and more lateral external intercostals, and the parasternal portion of the internal intercostal muscles. Both the external intercostal muscles and the parasternal portion of the internal intercostal muscles elevate the ribs.

5. Inspiration is the phase of ventilation in which air enters the lungs. It is initiated by contraction of the inspiratory muscles:

Diaphragm – flattens, extending the superior/inferior dimension of the thoracic cavity.

External intercostal muscles – elevates the ribs and sternum, extending the anterior/posterior dimension of the thoracic cavity.

The action of the inspiratory muscles results in an increase in the volume of the thoracic cavity. As the lungs are held against the inner thoracic wall by the pleural seal, they also undergo an increase in volume.

As per Boyle’s law, an increase in lung volume results in a decrease in the pressure within the lungs. The pressure of the environment external to the lungs is now greater than the environment within the lungs, meaning air moves into the lungs down the pressure gradient.

6. Airway resistance refers to degree of resistance to the flow of air through the respiratory tract during inspiration and expiration. The degree of resistance depends on many things, particularly the diameter of the airway and whether flow is laminar or turbulent. Alveolar expansion is also dependent on surfactant,  so we will consider the physiology and importance of this substance.

7. The decrease of lung compliance in pulmonary edema underlies ventilator-induced lung injury. However, the cause of the decrease in compliance is unknown. We tested the hypothesis that in pulmonary edema, the mechanical effects of liquid-filled alveoli increase tissue stress in adjacent air-filled alveoli.

  In pulmonary edema, liquid-filled alveoli induce mechanical stress on air-filled alveoli, reducing the compliance of air-filled alveoli, and hence overall lung compliance.

8. In breath holding with air, oxygen initially represents less than 20 5% of the lung volume. Since a large fraction of Nz is present, uptake of 02 progressively reduces the concentration and partial pressure of 02 in the lungs. As a result, the 02 saturation of arterial blood decreases

9. They do not stop during breath holding

10. This study tested three possible mechanisms that could explain the prolonged breath-holds (BH) previously observed in humans during submersion in 35 degrees C (thermoneutral) water, including a reduced metabolism, a decreased CO2 sensitivity, and an increased CO2 storage capacity.

oxygen initially represents less than 20 5% of the lung volume. Since a large fraction of Nz is present, uptake of 02 progressively reduces the concentration and partial pressure of 02 in the lungs. As a result, the 02 saturation of arterial blood decreases.