During the depiction of CPR in the ICU toward the end of this episode. The patient is never receiving any oxygen except for a nasal cannula. There is an actor pretending he's "bagging" her using an Ambu bag. But that bag is attached to an endotracheal tube (used as an artificial airway in unconscious patients) that the actor is holding in his hand near the head of the actress. In a real CPR that endotracheal tube would have either been in the patients nose or mouth. ET tubes are long enough to reach the patients lung and allow medical staff to breathe for the patient. This was a fairly poor depiction of a code.
A person does not recover from a cardiac arrest and resuscitation and look and talk like nothing has happened as is depicted in the post-CPR scene. They should have made it the next day or two, not just a few minutes later.
It's strange the writers chose to have Rosewood find the body floating in the pool, and he does nothing but stare at it. Anyone in the medical profession that finds someone floating in the water would attempt to remove and resuscitate the person. They had just determined that the wine was cold and someone had been alive in that house recently. CPR would have been the first thing on any physician's mind in this situation.