After abdominal surgery, a patient shows low blood pressure and dusky color. What should the respiratory therapist assess first?

In the context of a patient who has undergone abdominal surgery and is now presenting with low blood pressure and dusky coloration, assessing the hemoglobin level is critical. These symptoms could indicate potential complications such as hemorrhage or significant blood loss, which can lead to inadequate oxygenation and perfusion.

By checking the hemoglobin level first, the respiratory therapist can determine if the patient is anemic or experiencing a drop in blood volume due to bleeding. Low hemoglobin levels may be contributing to their low blood pressure and dusky skin tone, which are signs of inadequate oxygen delivery to the tissues.

Monitoring INR, instituting volume ventilation, and administering anticoagulant therapy are steps that may be necessary later, depending on the findings. However, addressing the patient's immediate hemodynamic status and oxygenation capability through the assessment of hemoglobin is the most urgent and relevant initial action in this scenario.