Undiagnosed diaphragmatic hernia--the importance of preanesthetic evaluation.

A 6-year-old, neutered male, Pembroke Welsh corgi was presented for hind limb paralysis. After anesthetic induction, marked cyanosis and hypotension were noted. Diaphragmatic hernia was diagnosed based upon radiographic findings. Risks and complications associated with undiagnosed diaphragmatic hernia and the importance of thorough physical examination and patient assessment are discussed.