Prolonged apnea of an oral surgery patient after administration of succinylcholine.

To properly diagnose the presence of a genetic pseudocholinesterase variation, the family history is important. Furthermore, the DN and pseudocholinesterase tests are most useful, but if facilities for these are not available, one should be wary of patients with abnormal liver function tests. Certainly medical history, family medical history, laboratory evaluation, and knowledge of the disease processes should avoid unnecessary complications.