Ariel L. Shiloh

Ultrasound-guided catheterization of the radial artery: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND Ultrasound guidance commonly is used for the placement of central venous catheters (CVCs). The Agency for Healthcare Research and Quality recommends the use of ultrasound for CVC placement as one of its 11 practices to improve patient care. Despite increased access to portable ultrasound machines and comfort with ultrasound-guided CVC access, fewer clinicians are familiar with ultrasound-guided techniques of arterial catheterization. The goal of this systematic review and meta-analysis was to determine the utility of real-time two-dimensional ultrasound guidance for radial artery catheterization. METHODS A comprehensive literature search of Medline, Excerpta Medica Database, and the Cochrane Central Register of Controlled Trials by two independent reviewers identified prospective, randomized controlled trials comparing ultrasound guidance with traditional palpation techniques of radial artery catheterization. Data were extracted on study design, study size, operator and patient characteristics, and the rate of first-attempt success. A meta-analysis was constructed to analyze the data. RESULTS Four trials with a total of 311 subjects were included in the review, with 152 subjects included in the palpation group and 159 in the ultrasound-guided group. Compared with the palpation method, ultrasound guidance for arterial catheterization was associated with a 71% improvement in the likelihood of first-attempt success (relative risk, 1.71; 95% CI, 1.25-2.32). CONCLUSIONS The use of real-time two-dimensional ultrasound guidance for radial artery catheterization improved first-pass success rate.

Monitoring of the Adult Patient on Venoarterial Extracorporeal Membrane Oxygenation

Venoarterial extracorporeal membrane oxygenation (VA ECMO) provides mechanical support to the patient with cardiac or cardiopulmonary failure. This paper reviews the physiology of VA ECMO including the determinants of ECMO flow and gas exchange. The efficacy of this therapy may be determined by assessing patient hemodynamics and device flow, overall gas exchange support, markers of adequate oxygen delivery, and pulsatility of the arterial blood pressure waveform.

The Diagnostic and Therapeutic Impact of Point-of-Care Ultrasonography in the Intensive Care Unit.

Purpose: In light of point-of-care ultrasonography’s (POCUS) recent rise in popularity, assessment of its impact on diagnosis and treatment in the intensive care unit (ICU) is of key importance. Methods: Ultrasound examinations were collected through an ultrasound reporting software in 6 multidisciplinary ICU units from 3 university hospitals in Canada and the United States. This database included a self-reporting questionnaire to assess the impact of the ultrasound findings on diagnosis and treatment. We retrieved the results of these questionnaires and analyzed them in relation to which organs were assessed during the ultrasound examination. Results: One thousand two hundred and fifteen ultrasound studies were performed on 968 patients. Intensivists considered the image quality of cardiac ultrasound to be adequate in 94.7% compared to 99.7% for general ultrasound (P < .001). The median duration of a cardiac examination was 10 (interquartile range [IQR] 10) minutes compared to 5 (IQR 8) minutes for a general examination (P < .001). Overall, ultrasound findings led to a change in diagnosis in 302 studies (24.9%) and to a change in management in 534 studies (44.0%). A change in diagnosis or management was reported more frequently for cardiac ultrasound than for general ultrasound (108 [37.1%] vs 127 [16.5%], P < .001) and (170 [58.4%] vs 270 [35.1%], P < .001). Assessment of the inferior vena cava for fluid status emerged as the critical care ultrasound application associated with the greatest impact on management. Conclusion: Point-of-care ultrasonography has the potential to optimize care of the critically ill patients when added to the clinical armamentarium of the intensive care physician.

Ultrasound-guided cannulation of the femoral vein in electrophysiological procedures: a systematic review and meta-analysis.

Aims In an effort to minimize periprocedural stroke risk, increasingly, electrophysiological (EP) procedures are being performed on anticoagulation. The decrease in stroke has been accompanied by an increase in potentially devastating vascular access complications. Ultrasound guidance for femoral vein cannulation reduces complications in other applications. The aim of this study is to determine the utility of real-time two-dimensional (2D) ultrasound guidance for femoral vein cannulation in EP. Methods and results A comprehensive literature search of Medline, Embase, Google Scholar, and the Cochrane Central Register of Controlled Trials was performed. Five years of conference abstracts from the Heart Rhythm Society, European Heart Rhythm Association, and European Cardiac Arrhythmia Society were reviewed. Two independent reviewers identified trials comparing ultrasound-guided with standard cannulation in EP procedures. Data were extracted on study design, study size, operator and patient characteristics, use of anticoagulation, vascular complication rates, first-pass success rate, and inadvertent arterial puncture. Four trials, with a total of 4065 subjects, were included in the review, with 1848 subjects in the ultrasound group and 2217 subjects in the palpation group. Ultrasound guidance for femoral vein cannulation was associated with a 60% reduction of major vascular bleeding (relative risk, 0.40; 95% confidence interval, 0.28-0.91). Additionally, there was a 66% reduction in minor vascular complications (relative risk, 0.34; 95% confidence interval, 0.15-0.78). Conclusion The use of real-time 2D ultrasound guidance for femoral vein cannulation decreases access-related bleeding rates and life-threatening vascular complications.

Daytime Versus Nighttime Extubations A Comparison of Reintubation, Length of Stay, and Mortality

Purpose: Despite studies regarding outcomes of day versus night medical care, consequences of nighttime extubations are unknown. It may be favorable to extubate patients off-hours, as soon as weaning parameters are met, since this could decrease complications and shorten length of stay (LOS). Conversely, nighttime extubation could be deleterious, as staffing varies during this time. We hypothesized that patients have similar reintubation rates, irrespective of extubation time. Methods: A retrospective cohort study performed at 2 hospitals within a tertiary academic medical center included all adult intensive care unit (ICU) patients extubated between July 01, 2009 and May 31, 2011. Those extubated due to withdrawal of support were excluded. The nighttime group included patients extubated between 7:00 pm and 6:59 am and the daytime group included patients extubated between 7:00 am and 6:59 pm. Results: Of 2240 extubated patients, 1555 were extubated during the day and 685 were extubated at night. Of these, 119 (7.7%) and 26 (3.8%), respectively, were reintubated in 24 hours with likelihood of reintubation significantly lower for nighttime than daytime after multivariable adjustment (odds ratio [OR] = 0.5, 95% confidence interval [CI] 0.3-0.9, P = .01), with a similar trend for reintubation within 72 hours (OR = 0.7, 95% CI = 0.5-1.0, P = .07). There was a trend toward decreased mortality for patients extubated at night (OR = 0.6, 95% CI = 0.3-1.0, P = .06). There was also a significantly lower LOS for patients extubated at night (P = .002). In a confirmatory frequency-matched analysis, there was no significant difference in reintubation proportion or mortality, but LOS was significantly less in those extubated at night. Conclusions: Intensive care unit extubations at night did not have higher likelihood of reintubation, LOS, or mortality compared to those during the day. Since patients should be extubated as soon as they meet parameters in order to potentially decrease complications of mechanical ventilation, these data provide no support for delaying extubation until daytime.

Optimization of Cannula Visibility during Ultrasound-Guided Subclavian Vein Catheterization, via a Longitudinal Approach, by Implementing Echogenic Technology

Objective. One limitation of ultrasound-guided vascular access is the technical challenge of visualizing the cannula during insertion into the vessel. We hypothesized that the use of an echogenic vascular cannula (EC) would improve visualization when compared with a nonechogenic vascular cannula (NEC) during real-time ultrasound-guided subclavian vein (SCV) cannulation in the ICU. Material and Methods. Eighty mechanically ventilated patients were prospectively enrolled in a randomized study that was conducted in a medical-surgical ICU. Forty patients underwent EC and 40 patients were randomized to NEC. The procedure was ultrasound-guided SCV cannulation via the infraclavicular approach on the longitudinal axis. Results. The EC group exhibited increased cannula visibility as compared to the NEC group (92%±3% versus 85 ± 7%, resp., P < 0.01). There was strong agreement between the procedure operators and independent observers (k = 0.9, 95% confidence intervals assessed by bootstrap analysis = 0.87 to 0.93; P < 0.01). Access time (12.1 s ± 6.5 versus 18.9 s ± 10.9) and the perceived technical difficulty of the ultrasound method (4.5 ± 1.5 versus 7.5 ± 1.5) were both decreased in the EC group compared to the NEC group (P < 0.05). Conclusions. Echogenic technology significantly improved cannula visibility and decreased access time and technical complexity optimizing thus real-time ultrasound-guided SCV cannulation via a longitudinal approach.

Ultrasound-guided subclavian and axillary vein cannulation via an infraclavicular approach: In the tradition of Robert Aubaniac.

Crit Care Med 2012 Vol. 40, No. 10 DOI: 10.1097/CCM.0b013e31825f78c3 allows measurement of changes in the perfusion of the renal cortical microcirculation which, experimentally, parallel changes in clearance measurements of renal plasma flow in humans (5). To conclude, we believe that CPCMRI is a powerful technique that complements both standard and contrastenhanced ultrasound assessment of the renal circulation and may enable a better understanding the physiological meaning of these measurements in differing clinical contexts. As well as being a primary investigatory modality, CPC-MRI could provide an invaluable method to calibrate and validate ultrasound techniques, including contrast-enhanced ultrasonography, which might be more widely applicable in clinical practice. The authors have not disclosed any potential conflicts of interest.

Online testing from Google Docs™ to enhance teaching of core topics in critical care: A pilot study

Background: Recent evidence suggests that retrieval practice, or learning by testing, may lead to more effective knowledge retention than standard educational techniques. Aim: The purpose of this pilot project was to document successful teaching of evidence-based guidelines in critical care by augmenting interactive problem-based teaching sessions with online pre- and post-testing. Methods: We used a free, internet-based document collaboration system (Google Docs™) to develop and share pre-tests and pre-session teaching files with the fellows. At the teaching sessions the pre-tests were reviewed interactively, and additional case-based questions were presented. One week after the sessions, the fellows were sent a post-test and a post-session survey. Results of the pre- and post-tests as well as the post-session surveys were tabulated by the document collaboration system. Results: The mean score was 54.6% (SD = 21.4%) on the pre-tests and 87.0% (SD = 15.8%) on the post-tests (p < 0.01). On a scale of 1–10, the median ratings given by the fellows were 9.5 (IQR = 9–10) for utility of the teaching sessions, 9 for utility of the test questions (IQR = 9–10), and 10 (IQR = 9–10) for utility of the teaching files. Conclusion: Google Docs™ can be successfully used to integrate retrieval practice into the teaching of evidence-based guidelines in critical care.

Echogenic Technology Improves Cannula Visibility during Ultrasound-Guided Internal Jugular Vein Catheterization via a Transverse Approach

Objective. Echogenic technology has recently enhanced the ability of cannulas to be visualized during ultrasound-guided vascular access. We studied whether the use of an EC could improve visualization if compared with a nonechogenic vascular cannula (NEC) during real-time ultrasound-guided internal jugular vein (IJV) cannulation in the intensive care unit (ICU). Material and Methods. We prospectively enrolled 80 mechanically ventilated patients who required central venous access in a randomized study that was conducted in two medical-surgical ICUs. Forty patients underwent EC and 40 patients were randomized to NEC. The procedure was ultrasound-guided IJV cannulation via a transverse approach. Results. The EC group exhibited increased visibility as compared to the NEC group (88%  ± 8% versus 20%  ± 15%, resp. P < 0.01). There was strong agreement between the procedure operators and independent observers (k = 0.9; 95% confidence intervals assessed by bootstrap analysis = 0.87–0.95; P < 0.01). Access time (5.2 s ± 2.5 versus 10.6 s ± 5.7) and mechanical complications were both decreased in the EC group compared to the NEC group (P < 0.05). Conclusion. Echogenic technology significantly improved cannula visibility and decreased access time and mechanical complications during real-time ultrasound-guided IJV cannulation via a transverse approach.

Being a Successful Medically Trained Surgical Intensivist Valuable Lessons Gained From Experience

Despite the growing demand for board- certified intensivists in the United States, the roles for medically trained intensivists (MTIs) in leadership positions in surgical ICUs remain limited. This report explores some of the challenges facing internal medicine (IM) critical care fellows who are considering careers as surgical intensivists or MTIs who are moving to a surgical ICU. A practical framework is provided for attaining these jobs and thriving in these positions once obtained. The article explores the nuances between medical and surgical ICUs and concludes by describing how surgical critical care can be a gratifying career for the IM-trained intensivist and an asset to the surgical ICU.