The clinical, occupational and financial outcomes associated with a bespoke specialist clinic for military aircrew-a cohort study.

OBJECTIVES: To assess the clinical, occupational and financial outcomes of a new Clinical Aviation Medicine Service (CAMS) for UK military personnel. METHODS: Consecutive patients over a 2 year period were included. Predictors of flying restrictions at referral and final outcome following consultation were modelled using logistic regression. National Health Service (NHS) Payment by Results tariffs and Defence capitation data were used to assess the financial impact of the service. RESULTS: Eight hundred and sixteen new referrals (94.5% male, median age 45 years (range 19-75)) were received and 1025 consultations performed. Cardiovascular disease was the commonest reason for referral. CAMS clinical activity cost at NHS tariff was £453 310 representing a saving of £316 173 (£137 137 delivery cost). In total, 310/816 (38%) patients had employment restrictions on referral and 49.0% of this group returned to full employment following their initial consultation. Compared with cardiology, general medicine and respiratory patients were more likely to have been occupationally restricted prior to referral (50 vs. 35%, OR 1.81; 95% CI 1.18-2.76, P values=0.006 and 53 vs. 35%, OR 2.12; 95% CI 1.15-3.90, P values = 0.016, respectively). Overall 581/816 (71.2%) of patients returned to unrestricted employment while 98/816 (12.0%) were unable to continue in any aircrew role. The service saved 7000 lost working days per year at an estimated occupational saving of ∼£1 million per annum. CONCLUSIONS: This bespoke service has allowed rapid, occupationally relevant clinical care to be delivered with both time and financial savings. The model may have significant occupational and financial relevance for other environmental and occupational medical organizations.

Clinical validation of dual-source dual-energy computed tomography (DECT) for coronary and valve imaging in patients undergoing trans-catheter aortic valve implantation (TAVI).

AIM: To assess the validity of virtual non-contrast (VNC) reconstructions for coronary artery calcium (CACS) and aortic valve calcium scoring (AVCS) in patients undergoing trans-catheter aortic valve implantation (TAVI). MATERIALS AND METHODS: Twenty-three consecutive TAVI patients underwent a three-step computed tomography (CCT) acquisition: (1) traditional CACS; (2) dual-energy (DE) CT coronary angiogram (CTCA); and (3) DE whole-body angiogram. Linear regression was used to model calcium scores generated from VNC images with traditional scores to derive a conversion factor [2.2 (95% CI: 1.97-2.58)]. The effective radiation dose for the TAVI protocol was compared to a standard control group. Bland-Altman analysis and weighted k-statistic were used to assess inter-method agreement for absolute score and risk centiles. RESULTS: CACS and AVCS from VNC reconstructions correlated well with traditional scores (r = 0.94 and r = 0.86; both p < 0.0001). There was excellent agreement between VNC and non-contrast coronary calcium scores [mean difference -71.8 (95% limits of agreement -588.7 to 445.1)], with excellent risk stratification into risk centiles (k = 0.99). However, the agreement was weaker for the aortic valve [mean difference -210.6 (95% limits of agreement -1233.2 to 812)]. Interobserver variability was excellent for VNC CACS [mean difference of 6 (95% limits of agreement 134.1-122.1)], and AVCS [mean difference of -16.4 (95% limits of agreement 576 to -608.7)]. The effective doses for the DE TAVI protocol was 16.4% higher than standard TAVI protocol (22.7 versus 19.5 mSv, respectively) accounted for by the DE CTCA dose being 47.8% higher than that for a standard CTCA [9.9 (5.6-14.35) versus 6.7 (1.17-13.72) mSv; p < 0.01). CONCLUSIONS: CACS and AVCS can be accurately quantified, and patients can be risk stratified using DECT VNC reconstructions. However, the dose from DE CTCA is significantly greater than the standard single-energy CTCA precluding the use of this technology in routine clinical practice.