Which projection is typically included in an acute abdominal series?

In an acute abdominal series, the PA (posteroanterior) chest projection is typically included to evaluate the presence of free air under the diaphragm, which can indicate conditions such as perforation in the abdominal cavity. The PA chest view helps in assessing the lungs and diaphragm, which can provide essential information about the patient's overall condition and any potential complications arising from abdominal issues.

This chest projection is particularly valuable in an acute setting as it can be performed quickly and offers critical insights that may influence further diagnostic decisions. The other imaging views listed may not be standard components of an acute abdominal series, as they serve different purposes in the assessment of abdominal or thoracic pathology.