During exercise, both QO2 and QCO2 increases as well as cardiac output, Qa. Supp

Question

During exercise, both QO2 and QCO2 increases as well as cardiac output, Qa. Suppose that during exercise QO2 increases to 2000 mL/min and the respiratory quotient remains at 0.8, and that Qa increases to 18 L/min. Assume that PaO2 remains at 95 mmHg, that O2 saturation is at 98% and PaO2 is 40 mmHg and that blood [Hb] = 15 g %. A. What is the total arterial content of O2? B. What is the venous content of O2? C. What is the QCO2? D. Determine the new alveolar ventilation from the alveolar ventilation equation.

Explanation / Answer

During exercise the muscles require more energy. Aerobic production in muscles results in increased gas exchange at the lungs,because more oxygen is taken in and more carbondioxide is released.

Blood transports these merabolic gases to and from the tissues.oxygen consumption increases linearly with increasing work rate at submaximal intensities.Breathing cpacity however doesn't reaches its maximum even during strenuous exercise and it is not responsible for the limitation in oxygen delivery to muscles seen during high intensity activity.Haemoglobin continues to be fully saturated with oxygen throughout exercise in persons with normal respiratory function.

CHANGES IN ARTERIAL BLOOD GASES:

The changes which occur in arterial pH, PO2 and PCO2 values during exercise are usually small.Arterial PO2 often rises slightly because of hyperventilation athough it may eventually fall at high work rates.During vigorous exercise ,when sufficient oxygen for flux through the Krebs cycle is not available, increased reliance on glycolysis results in increased accumulation of lactic acid, which initially leads to an increase in Paco2.However , this is counteracted by the stimulation of ventilation and as a result Paco2 is decreased.

1. The total arterial content of oxygen 20.1 ml O2/100ml

arterial oxygen content(Equation)=(Hgb x 1.36 x SaO2)+ (0.031 X PaO2).

SaO2= Percent of haemoglobin satutrated with oxygen

PaO2= arterial oxygen partial pressure

2. venous blood of oxygen can be is 199.93

can be calculated by using equation that is

CVO2=(Hgb x 13.4 x O2 Vsat/100)+(PVO2 x0.031)

3.QCO2 means respiratory quotient of carbondioxide released from the lungs

4.Alveolar ventilation can be calcuated using formula

(tidal volume- dead space)x respiratory rate =(500-150) x 0.8=380

0.8 is the respiratory quotient

Related Questions

Navigate

• Browse (All)
• Browse D
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.