Assessment of Image Quality of Repeated Limited Transthoracic Echocardiography After Cardiac Surgery.

OBJECTIVES: The use of limited transthoracic echocardiography (TTE) has been restricted in patients after cardiac surgery due to reported poor image quality. The authors hypothesized that the hemodynamic state could be evaluated in a high proportion of patients at repeated intervals after cardiac surgery. DESIGN: Prospective observational study. SETTING: Tertiary university hospital. PARTICIPANTS: The study comprised 51 patients aged 18 years or older presenting for cardiac surgery. INTERVENTIONS: Patients underwent TTE before surgery and at 3 time points after cardiac surgery. Images were assessed offline using an image quality scoring system by 2 expert observers. Hemodynamic state was assessed using the iHeartScan protocol, and the primary endpoint was the proportion of limited TTE studies in which the hemodynamic state was interpretable at each of the 3 postoperative time points. MEASUREMENTS AND MAIN RESULTS: Hemodynamic state interpretability varied over time and was highest before surgery (90%) and lowest on the first postoperative day (49%) (p<0.01). This variation in interpretability over time was reflected in all 3 transthoracic windows, ranging from 43% to 80% before surgery and from 2% to 35% on the first postoperative day (p<0.01). Image quality scores were highest with the apical window, ranging from 53% to 77% across time points, and lowest with the subcostal window, ranging from 4% to 70% across time points (p< 0.01). CONCLUSIONS: Hemodynamic state can be determined with TTE in a high proportion of cardiac surgery patients after extubation and removal of surgical drains.

Use of dexmedetomidine as a sedative and analgesic agent in critically ill adult patients: a meta-analysis.

PURPOSE: To assess the effects of using dexmedetomidine as a sedative and analgesic agent on length of intensive care unit (ICU) stay, duration of mechanical ventilation, risk of bradycardia, and hypotension in critically ill adult patients. METHODS: Two researchers searched MEDLINE, EMBASE, and the Cochrane controlled trial register independently for randomized controlled trials comparing dexmedetomidine with a placebo or an alternative sedative agent, without any language restrictions. RESULTS: A total of 2,419 critically ill patients from 24 trials were subject to meta-analysis. Dexmedetomidine was associated with a significant reduction in length of ICU stay [weighted mean difference -0.48 days, 95% confidence interval (CI) -0.18 to -0.78 days, P = 0.002], but not duration of mechanical ventilation, when compared with an alternative sedative agent. There was, however, significant heterogeneity in these two outcomes between the pooled studies. Dexmedetomidine was associated with increased risk of bradycardia requiring interventions in studies that used both a loading dose and maintenance doses >0.7 microg kg(-1) h(-1) [relative risk (RR) 7.30, 95% CI 1.73-30.81, P = 0.007]. Risks of hypotension requiring interventions (RR 1.43, 95% CI 0.78-2.6, P = 0.25), delirium (RR 0.79, 95% CI 0.56-1.11, P = 0.18), self-extubation, myocardial infarction, hyperglycemia, atrial fibrillation, and mortality were not significantly different between dexmedetomidine and traditional sedative and analgesic agents. CONCLUSIONS: Significant heterogeneity existed between the pooled studies. The limited evidence suggested that dexmedetomidine might reduce length of ICU stay in some critically ill patients, but the risk of bradycardia was significantly higher when both a loading dose and high maintenance doses (>0.7 microg kg(-1) h(-1)) were used.