To assess intubation management in difficult airway patients by performing a multidisciplinary pre-operative examination of the airway using a flexible fibre-optic laryngoscope.

Patients with a known but stable difficult airway were evaluated prior to surgery in the pre-operative holding suite by both an ENT surgeon and an anaesthesiologist via a fibre-optic laryngeal examination.

Performing a pre-operative fibre-optic examination of the difficult airway led to a change in intubation strategy in 6 out of 12 cases. Intubation ‘first-pass’ success occurred in 9 out of 12 (75 per cent) of our patients.

By performing a multidisciplinary airway examination immediately prior to surgery, a safe plan to intubate on the initial attempt was developed. This resulted in improved first-pass success at intubation compared to historical data.

The association between surgery with general anesthesia (exposure) and cognition (outcome) among older adults has been studied with mixed conclusions. We revisited a recent analysis to provide missing data education and discuss implications of biostatistical methodology for informative dropout following dementia diagnosis.

We used data from the Mayo Clinic Study of Aging, a longitudinal study of prevalence, incidence, and risk factors for mild cognitive impairment (MCI) and dementia. We fit linear mixed effects models (LMMs) to assess the association between anesthesia exposure and subsequent trajectories of cognitive z-scores assuming data missing at random, hypothesizing that exposure is associated with greater decline in cognitive function. Additionally, we used shared parameter models for informative dropout assuming data missing not at random.

A total of 1948 non-demented participants were included. Median age was 79 years, 49% were female, and 16% had MCI at enrollment. Among median follow-up of 4 study visits over 6.6 years, 172 subjects developed dementia, 270 died, and 594 participants underwent anesthesia. In LMMs, exposure to anesthesia was associated with decline in cognitive function over time (change in annual cognitive z-score slope = −0.063, 95% CI: (−0.080, −0.046), p < 0.001). Accounting for informative dropout using shared parameter models, exposure was associated with greater cognitive decline (change in annual slope = −0.081, 95% CI: (−0.137, −0.026), p = 0.004).

We revisited prior work by our group with a focus on informative dropout. Although the conclusions are similar, we demonstrated the potential impact of novel biostatistics methodology in longitudinal clinical research.