Carbon dioxide exchange, on the other hand, is not affected by an abnormal ratio of ventilation and blood flow as long as the increase in ventilation that is required to maintain carbon dioxide excretion in overventilated alveoli can be achieved.
In healthy lungs there is a narrow distribution of the ratio of ventilation to blood flow throughout the lung that is centred around a ratio of 1 to 1.
Normally, the ratio of ventilation to perfusion is about one-to-one; the volume of air entering the alveoli (ventilation) is about equal to that of blood in the capillaries around them (perfusion).
When inflammatory nodules, ratio of ventilation and blood flow changed, the pulmonary arteries became narrow or occlusive, and bronchial artery became expanded.
To quantify the effect of PEEP on ventilation distribution, we calculated the median of the log ratio of ventilation for each region and then the standard deviation of these medians across the five different regions at both PEEP levels.
To evaluate CPR performance, the training mannequin recorded various effectiveness parameters, such as the ratio of ventilation to chest compressions, depth of chest compressions, frequency of compressions, correct head tilt and chin lift, and correct breathing volumes.
These include the hematocrit, the (euoxic) pulmonary vascular resistance (as reflected by the pulmonary hypertension), the ratio of ventilation to metabolic rate (as reflected by arterial/end-tidal P co2), the cardiac output, and possibly cardiac sympathetic tone (as reflected by an increased heart rate).
Because measurements for all four ventilatory conditions were made in each animal and because the log ratio of ventilation with a tidal volume of 12 ml/kg to a tidal volume of 6 ml/kg is not independent among the five regions within any given animal, we could not perform a standard statistical analysis looking at differences between the five regions at different PEEP levels.
The need for using individual slopes and intercepts instead of mean values in assessing minute ventilation levels at the individual level is underlined by figures 3 and 4. Minute ventilation levels during cycling and ratios of minute ventilation of cyclists to car passengers can differ widely when calculated using the mean regression coefficients instead of using the individual coefficients.
The mean ratios of minute ventilation of cyclists compared to car passengers for both men and women are in line with the ratios calculated using personal coefficients.
