Contra-indications to Intravenous Contrast Medium

• Impaired renal function
• History of prior allergic reaction to iodinated contrast medium
• Severe asthma or congestive heart failure
• Diabetic patient on metformin
• Multiple myeloma or sickle-cell anemia

Useful rules of thumb

• Gaseous distension of small bowel + no gas in the colon = complete small bowel obstruction
• Significant gaseous distension of small bowel + minimal quantity of colonic gas = partial small bowel obstruction
• Significant gaseous distension of both the small bowel and the colon = paralytic ileus
• Significant gaseous distension of the colon + minimal distention of the small bowel = colonic obstruction or pseudo-obstruction

Chest X ray PA normal lebelled

L:	Lung
R:	Rib
T:	Trachea
AK:	Aortic knob
A:	Ascending aorta
H:	Heart
V:	Vertebra
P:	Pulmonary artery
S:	Spleen