Question

A 60 kg (132 lb) female patient with congestive heart failure is receiving NPPV with an IPAP of 16 cm H₂O, EPAP of 10 cm H₂O, and FIO₂ of 0.70. Available laboratory data includes: pH 7.40, PaCO₂ 42 torr; PaO₂ 145 torr; HCO₃ 26 mEq/L, SaO₂ 99%, CVP 10 cm H₂O. Breath sounds reveal a few fine bibasilar crackles. This situation should be described as

A. shunting.
B. hypoventilation.
C. hyperoxygenation.
D. fluid overload.

Answer 1

The patient with congestive heart failure and bibasilar crackles, a normal blood gas analysis, and high oxygen saturation is best described as experiencing fluid overload rather than shunting, hypoventilation, or hyperoxygenation.

Step-by-step explanation:

The patient with congestive heart failure displays a paradox of having a PaO2 of 145 torr with an FIO2 of 0.70, which suggests that her lungs are effectively oxygenating the blood. The presence of bibasilar crackles in the lung may indicate fluid in the basal parts of the lungs, which is a classical sign of congestive heart failure. Given these findings, her blood gas analysis showing a normal pH and PaCO2, and her high SaO2 of 99%, the clinical situation is not consistent with shunting, hypoventilation, or hyperoxygenation. Instead, they are indicative of fluid overload, as elevated central venous pressure and crackles in the lung bases are typical of this condition.