Difficult laryngoscopy and diabetes mellitus.

The incidence of difficult laryngoscopy was determined retrospectively in 40 diabetic patients having pancreas transplantations and in 75 diabetic and 112 nondiabetic patients having kidney transplantations. Diabetes was associated with a significant increase in the proportion of patients having difficult laryngoscopies in patients having renal transplants: 0.027 in patients without diabetes; 0.320 in patients with diabetes. The incidence of difficult laryngoscopy in diabetic recipients of cadaveric kidneys (0.419) was not significantly different from that in diabetic recipients of pancreas transplants (0.40), but significantly higher than that in diabetics given kidneys from living donors (0.187). Although cadaveric recipients were older than recipients of kidneys from living donors (40.8 v. 31.6 years), age at the time of transplantation was not a significant predictor of difficulty in laryngoscopy. Groups were otherwise matched for clinical, morphologic, hematologic, and biochemical indices. Diabetic stiff joint syndrome (SJS), which predisposes a subset of Type I diabetic patients to rapidly progressive microvascular disease and subsequent need for renal and/or pancreas transplantation, may lead to difficult laryngoscopy because of involvement of the atlanto-occipital joint.