Prospective Clinical Trial Comparing IV Esmolol to IV Metoprolol in CT Coronary Angiography: Effect on Hemodynamic, Technical Parameters and Cost.

BACKGROUND: Intravenous [IV] esmolol, an alternative to IV metoprolol for coronary computed tomography angiography [CCTA], has shorter half-life that decreases the risk of prolonged hypotension. The primary aim was to prospectively compare IV esmolol alone to IV metoprolol alone for effectiveness in achieving heart rate [HR] of 60 beats per minute[bpm] during CCTA. The secondary aim was to compare hemodynamic response, image quality, radiation dose and cost. MATERIALS AND METHODS: Institutional Review Board approved prospective randomized study of 28 CCTA patients medicated in a 1:1 blinded match with IV esmolol or IV metoprolol to achieve HR of 60 bpm. Serial hemodynamic response was measured at 6 specified times. Two cardiac radiologists independently scored the image quality. RESULTS: Both IV esmolol and IV metoprolol achieved the target HR. IV esmolol resulted in significantly less profound and shorter duration of reduction in systolic blood pressure [BP] than IV metoprolol with a difference of -10, -14 and -9 mm Hg compared to -20, -26 and -25 mmHg at 2, 15 & 30 min respectively. No significant difference in HR at image acquisition, exposure window, radiation dose and image quality. Although IV esmolol was expensive, the overall cost of care was comparable to IV metoprolol due to shortened post CCTA observation period consequent to faster restoration of hemodynamic status. CONCLUSION: Comparison of IV esmolol and IV metoprolol demonstrate that both are effective in achieving the target HR but significantly faster recovery of HR and BP in patients who receive IV esmolol was found.

Enhanced pneumothorax visualization in ICU patients using portable chest radiography.

OBJECTIVE: Pneumothorax development can cause precipitous deterioration in ICU patients, therefore quick and accurate detection is vital. Portable chest radiography is commonly performed to exclude pneumothoraces but is hampered by supine patient position and overlying internal and external material. Also, the initial evaluation of the chest radiograph may be performed by a relatively inexperienced physician. Therefore, a tool that could significantly improve pneumothorax detection on portable radiography would be helpful in patient care. The aim of this study was to evaluate the clinical utility of novel enhancement software for pneumothorax detection in readers with varied clinical experience of detecting/excluding pneumothoraces on portable chest radiographs in ICU patients. SUBJECTS AND METHODS: 206 portable ICU chest radiographs, 103 with pneumothoraces, were processed with and without enhancement software and reviewed by 5 readers who varied in reading experience. Images were grouped for different complexity levels. RESULTS: The mean AUC for pneumothorax detection increased for 4/5 readers from 0.846-0.957 to 0.88-0.971 with a largest improvement for the reader with least experience. No significant change was noted for the reader with the longest reading experience. The image complexity had no impact on the interpretation result. CONCLUSION: Pneumothorax detection improves with novel enhancement software; the largest improvement is seen in less experienced readers.

Randomized controlled trial of relaxation music to reduce heart rate in patients undergoing cardiac CT.

OBJECTIVES: To evaluate the heart rate lowering effect of relaxation music in patients undergoing coronary CT angiography (CCTA), pulmonary vein CT (PVCT) and coronary calcium score CT (CCS). METHODS: Patients were randomised to a control group (i.e. standard of care protocol) or to a relaxation music group (ie. standard of care protocol with music). The groups were compared for heart rate, radiation dose, image quality and dose of IV metoprolol. Both groups completed State-Trait Anxiety Inventory anxiety questionnaires to assess patient experience. RESULTS: One hundred and ninety-seven patients were recruited (61.9 % males); mean age 56y (19-86 y); 127 CCTA, 17 PVCT, 53 CCS. No significant difference in heart rate, radiation dose, image quality, metoprolol dose and anxiety scores. 86 % of patients enjoyed the music. 90 % of patients in the music group expressed a strong preference to have music for future examinations. The patient cohort demonstrated low anxiety levels prior to CT. CONCLUSION: Relaxation music in CCTA, PVCT and CCS does not reduce heart rate or IV metoprolol use. Patients showed low levels of anxiety indicating that anxiolytics may not have a significant role in lowering heart rate. Music can be used in cardiac CT to improve patient experience. KEY POINTS: • Relaxation music does not reduce heart rate in cardiac CT • Relaxation music does not reduce beta-blocker use in cardiac CT • Relaxation music has no effect on cardiac CT image quality • Low levels of anxiety are present in patients prior to cardiac CT • Patients enjoyed the relaxation music and this results in improved patient experience.

Prospective study of intracranial translucency and the posterior brain in normal fetuses at the 11- to 13-week scan.

OBJECTIVES: To evaluate the ability of sonographers to prospectively identify intracranial translucency and posterior brain structures at 11 to 13 weeks and to evaluate measurement reproducibility of brain stem and brain stem-occipital bone diameters on stored images. METHODS: After specific training for intracranial translucency visualization, 10 nonphysician sonographers prospectively identified intracranial translucency at the 11- to 13-week scan, noting whether intracranial translucency was present, absent, or uncertain. If absent/uncertain, they documented the reason as spina bifida or an inadequate image (with reasons for the inadequate image). Measurements of brain stem and brain stem-occipital bone diameters were performed on stored images. Fifty randomly selected cases were reviewed for intraobserver and interobserver variability. RESULTS: In 313 singleton pregnancies, the posterior brain including intracranial translucency was evaluated; 293 (93.6%) had known pregnancy outcomes. None had open spina bifida, but 7 had chromosomal or congenital abnormalities. In the remaining 286 normal fetuses, intracranial translucency was seen in 275 (96%) and uncertain in 11 (4%), due to inadequate images (top 3 reasons were fetal position [n = 8], obesity [n = 5], and retroverted uterus [n = 4]). Fetal position and gestational age were significantly associated with intracranial translucency visualization (P < .05). Intraobserver and interobserver agreement rates were moderate for measurements of brain stem diameter (intraclass correlation coefficients, 0.59 and 0.57) and substantial for brain stem-occipital bone diameter (intraclass correlation coefficients, 0.76 and 0.61). Bland-Altman analysis revealed negligible intraobserver and interobserver differences in brain stem and brain stem-occipital bone diameter measurements. CONCLUSIONS: Intracranial translucency can be prospectively identified by trained sonographers in 96% of normal fetuses at 11 to 13 weeks. Measurements of brain stem and brain stem-occipital bone diameters are reproducible.