What is the appropriate next step for a patient with placenta previa and painless vaginal bleeding?

In the context of a patient with placenta previa and painless vaginal bleeding, the most appropriate next step is to perform a type and screen. This test is critical because it assesses the patient’s blood type and Rh factor, as well as checking for the presence of any antibodies. Given that the patient is experiencing vaginal bleeding, there is a risk for significant blood loss, and knowing the blood type facilitates any necessary transfusions.

Monitoring the patient's blood type and Rh status is an essential part of managing cases where there is a potential for hemorrhage, which is common with placenta previa. If the bleeding worsens or surgery is needed, having this information ready can be lifesaving.

In contrast, performing a pelvic exam could provoke additional bleeding and is generally avoided in suspected cases of placenta previa. Coagulation studies are not as immediately necessary in this scenario, as the primary concern is ensuring that the patient is prepared for potential interventions related to her bleeding and placental positioning. Similarly, a digital vaginal exam poses the risk of causing further trauma and bleeding, so it is not indicated in this setting. The focus should remain on stabilizing the patient and preparing for possible interventions rather than performing exams that could exacerbate the condition.