Utility of carotid duplex ultrasonography in a general inner-city hospital.

BACKGROUND: Carotid Duplex Ultrasonography (CDUS) is one of the non-invasive imaging modalities used to evaluate for carotid artery stenosis. However, it is often used in patients with coronary artery disease (CAD), peripheral artery disease (PAD), before heart surgery, syncope and non-specific neurological symptoms although its value is unclear. Our study aimed to further investigate the yield of CDUS in these conditions. METHODS: A retrospective analysis was conducted on 827 consecutive carotid ultrasounds ordered between March 2013 and August 2013 at Newark Beth Israel Medical Center. Clinical characteristics such as age, sex, smoking status, systemic hypertension, diabetes mellitus, CAD, PAD, carotid bruit and indications for carotid ultrasound were included. Significant cerebrovascular disease (sCBVD) was defined as greater than or equal to 50% diameter reduction in internal carotid arteries (ICA) or any degree of occlusion in vertebrobasilar system. RESULTS: Only 88 out of 827 (10.6%) patients had sCBVD. Using logistic regression analysis we identified age greater than 65 years (OR 2.1, 95% CI 1.2 to 3.7; P=0.006), carotid bruit (OR 7.8, 95% CI 3.6 to 16.6; P <0.001) and history of prior carotid endarterectomy or carotid artery stenting (OR 5.8, 95% CI 2.3 to 14.8; P <0.001) as significant predictors of sCBVD. CONCLUSIONS: Significant carotid artery stenosis is more likely in patients 65 years and older, presence of carotid bruit and prior CEA. On the other hand, it has low diagnostic yield in less than 65-year-old individuals, syncope and non-focal neurological symptoms. This highlights the need for better risk prediction models in order to promote optimal utilization.

Kairos positive airway pressure (KPAP) equals continuous PAP in effectiveness, and offers superior comfort for obstructive sleep apnea treatment.

STUDY OBJECTIVES: A recent study challenged the prevailing clinical view that maintaining inspiratory positive airway pressure (IPAP) is necessary for upper airway patency, demonstrating no differences in apnea hypopnea index (AHI) between continuous PAP (CPAP) with and without a resistor to reduce IPAP. In this study, we assessed the effect of Kairos PAP (KPAP), a new algorithm which features multiple drops in IPAP, only returning to therapeutic pressure near the end expiration, on sleep apnea severity and subjective comfort. METHODS: Two randomized clinical trials were conducted. In the Efficacy trial, the effect of KPAP vs. CPAP on AHI in PAP-treated OSA patients was examined using a split-night design, adjusting for period, sequence and fraction of supine sleep (mixed models). Unintentional leak differences between treatments were also examined. Exploratory analyses assessed the effect of KPAP vs. CPAP on key polysomnography outcomes. In the Comfort trial, we tested subjective preference for KPAP vs. CPAP at 9 and 13 cmH2O in PAP-naïve OSA patients. RESULTS: In the Efficacy trial (N = 48), KPAP reduced AHI more than CPAP (mean difference [95%CI]: -0.5 [-0.8, -0.2] events/h, P = 0.007). Unintentional leak was also reduced by over 50 % (-2.5 [-3.2, -1.7] L/min, P < 0.001). No significant change was observed in the exploratory variables assessed. In the Comfort trial (N = 150), 69 [61, 77] % and 84 [77, 89] % of participants preferred KPAP over CPAP at 9 and 13 cmH2O, respectively (P < 0.001). CONCLUSIONS: KPAP is as effective as CPAP in reducing respiratory events, but is more comfortable and potentially better tolerated.