NREMT Paramedic Practice

What compensatory mechanism occurs in the kidneys in response to respiratory acidosis?

1. Decreased bicarbonate reabsorption

2. Increased bicarbonate reabsorption

3. Increased hydrogen ion excretion

4. Decreased hydrogen ion excretion

The correct answer is: Increased bicarbonate reabsorption

In response to respiratory acidosis, the kidneys compensate by increasing the reabsorption of bicarbonate. Respiratory acidosis occurs when there is an accumulation of carbon dioxide in the blood, leading to a decrease in blood pH. To correct this, the kidneys enhance their ability to conserve bicarbonate, which is a base and helps to neutralize the acidity of the blood. By increasing bicarbonate reabsorption, the kidneys help elevate the bicarbonate concentration in the blood, thereby contributing to a higher blood pH and mitigating the acidic environment caused by respiratory issues. This compensatory mechanism can take several hours to days to fully implement, as the kidneys are involved in long-term regulation of acid-base balance, in contrast to the immediate responses of the respiratory system. In this context, it's important to note that while hydrogen ion excretion also plays a role in the kidneys' response to acid-base disturbances, the primary compensatory mechanism for respiratory acidosis specifically involves the increased reabsorption of bicarbonate to restore balance.