A 45 year old man had cancer of head of pancreas which has been removed. He has a history of longstanding heartburn. He now comes with rigid abdomen which is tender, temp 37.5C, BP 90/70mmHg, pulse 120bpm. What is the next step of the investigation?

The key is B. X-ray abdomen. [X-ray abdomen will help diagnosing perforation by showing gas under diaphragm. This is a case of perforated peptic ulcer with the features of shock, abdominal rigidity and raised temperature. Stress from serious disease and operation causes the body to produce higher amounts of acid, which can irritate preexisting ulcers leading to easy perforation].