A 72-year-old female calls EMS due to severe lower back pain and exhibits symptoms of shock. What condition is she most likely experiencing?

The most likely condition the 72-year-old female is experiencing, given her severe lower back pain and symptoms of shock, is an abdominal aortic aneurysm (AAA). This condition can present with sudden, severe pain in the back or abdomen, and as the aneurysm expands or ruptures, it can lead to significant internal bleeding. This bleeding is the primary reason for the symptoms of shock, which may include hypotension, tachycardia, and altered mental status due to decreased perfusion to vital organs.

In this case, risk factors for an AAA, such as age and possibly underlying cardiovascular disease, further support this diagnosis. Aneurysms are more common in older adults, particularly those with a history of hypertension, smoking, or vascular disease.

Other conditions may also cause lower back pain and shock; however, AAA aligns more closely with the combination of severe pain and hemodynamic instability presented in this scenario. Kidney stones could cause severe pain but are less likely to result in shock unless there is associated renal rupture, which is less common. Pulmonary embolism typically presents with chest pain and respiratory distress, and while a spinal fracture can cause significant pain, it would less likely produce shock unless there were significant internal injuries or bleeding.