Feasibility of common carotid artery point of care ultrasound in cardiac output measurements compared to invasive methods

BACKGROUND: Cardiac output (CO) measurement in the intensive care unit (ICU) requires invasive devices such as the pulmonary artery (PA) catheter or arterial waveform pulse contour analysis (PCA). This study tests the accuracy and feasibility of point of care ultrasound (POCUS) of the common carotid artery to estimate the CO non-invasively and compare it to existing invasive CO measurement modalities. METHODS: Patients admitted to the surgical and cardiothoracic ICU in a tertiary university-affiliated academic center during a 4-month period, with invasive hemodynamic monitoring devices for management, were included in this cohort study. Common carotid artery POCUS was performed to measure the CO and the results were compared to an invasive device. RESULTS: Intensivists and ICU fellows, using ultrasound of the common carotid artery, obtained the CO measurements. Images of the Doppler flow and volume were obtained at the level of the thyroid gland. Concurrent CO measured via invasive devices was recorded. The patient cohort comprised 36 patients; 52 % were females. The average age was 59 ± 13 years, and 66 % were monitored via PCA device and 33 % via PA catheter. Intraclass correlation coefficient (ICC) analysis demonstrated almost perfect correlation (0.8152) between measurements of CO via ultrasound vs. invasive modalities. The ICC between POCUS and the invasive measurement via PCA was 0.84 and via PA catheter 0.74, showing substantial agreement between the ultrasound and both invasive modalities. CONCLUSIONS: Common carotid artery POCUS offers a non-invasive method of measuring the CO in the critically ill population

Autonomic cerebral vascular response to sildenafil in diabetic patient

<p>Abstract</p> <p>Background</p> <p>Erectile dysfunction is a common problem in type 2 diabetic patients who are at higher risk of cerebrovascular events, and it's recorded with sildenafil, a drug which is primarily used for erectile dysfunction.</p> <p>Objectives</p> <p>We tested the hypothesis whether or not sildenafil modulates cerebrovascular reactivity (CVR) in patients with type 2 diabetes mellitus.</p> <p>Methods</p> <p>A total of 35 male participants were enrolled; eighteen with type 2 diabetes mellitus matched with seventeen normal individuals. Transcranial Doppler Ultrasonographic examination (TCD) was performed for all participants to insonate the middle cerebral artery (MCA) through a trans-temporal window. CVR was assessed by using breath holding (BH)-hyperventilation (HV) test, before and after oral 50 mg sildenafil; recordings were analyzed by using SPSS program version 12.</p> <p>Results</p> <p>In normal individuals, sildenafil did not result in statistically significant change in breath holding index (BHI) from 0.91 ± 0.11 to 0.81 ± 0.09 and full range of vasodilatation (FVD) from (59.4% ± 6.3%) to (53.7% ± 4.9%). In diabetic patients, giving sildenafil resulted in significant increase in BHI (from 0.74 ± 0.14 to 1.03 ± 0.14) and FVD (from 60.2% ± 4.96% to 74% ± 4.8%), (p < 0.05).</p> <p>Conclusion</p> <p>Sildenafil significantly improves CVR in type 2 diabetic patients but not in normal subjects.</p