Incidental Murmurs and the Elective Noncardiac Surgical Patient: A Case Report.

We present a case of left ventricular outflow tract (LVOT) obstruction detected by limited bedside transthoracic echocardiography (TTE). This involved a young and otherwise healthy patient presenting for elective hand surgery with a previously undetected cardiac murmur. It highlights the utility of bedside TTE as an assessment tool and shows the importance of anesthesiologists as perioperative physicians.

A Randomized Controlled Trial of Ultrasound Versus Nerve Stimulator Guidance for Axillary Brachial Plexus Block.

BACKGROUND: Ultrasound-guided techniques improve outcomes in regional anesthesia when compared with traditional techniques; however, this assertion has not been studied with novices. The primary objective of this study was to compare sensory and motor block after axillary brachial plexus block when performed by novice trainees allocated to an ultrasound- or nerve-stimulator-guided group. A secondary objective was to compare the rates of skill acquisition between the 2 groups. METHODS: This study was a prospective, randomized, observer-blinded, 2-arm controlled trial. Anesthesia trainees participating in this trial were novices to axillary brachial plexus block and sonography. All trainee participants underwent a standardized training program. The primary outcome was combined sensory and motor block in the relevant territories 30 minutes after completion of block. A global rating scale was used to assess trainee block performance. RESULTS: The study was ceased after 12 trainees completed 153 blocks. There was no difference between groups in combined motor/sensory score (P = 0.28) or as a function of block number (P = 0.38). There was no difference in onset between groups (P = 0.38). In both groups, there was an increase in the global rating scale score (P < 0.0001) and reduced preblock survey and block performance times (P = 0.001) with experience. CONCLUSIONS: We were unable to demonstrate a difference in the efficacy of axillary brachial plexus block performed by novices when ultrasound guidance was compared with a nerve stimulator technique. There was evidence of similarly improved clinical performance of novices in both groups.

Cardioplegia Dose Effect on Immediate Postoperative Alterations in Coronary Artery Flow Velocities After Congenital Cardiac Surgery.

Abnormalities in coronary artery (CA) flow detected by echocardiography are increasingly used to guide clinical decisions in patient management. Increased CA flow has been seen postoperatively in congenital cardiac surgery. This study sought to determine immediate postoperative changes in left anterior descending (LAD) CA flow velocities, and to investigate possible factors associated with these changes. CA flow in the proximal LAD was sampled with pulsed-wave Doppler during trans-esophageal echocardiography imaging in the immediate preoperative and postoperative studies in 46 subjects. The peak velocity, velocity time integral (VTI), VTI corrected for heart rate (VTIc), and VTI rate pressure product (VTIrpp) were determined. The percent change in each measure between the preoperative and postoperative study was calculated and compared to age, body surface area (BSA), cardiopulmonary bypass time, cross-clamp time, and number of cardioplegia (CP) doses. The pH, oxygen saturation, temperature, and hemoglobin concentration (Hb) were compared for those with and without increased flow characteristics. There was an overall increase in LAD flow parameters in subjects who underwent congenital cardiac surgery. There was a significant and positive correlation of percent change in VTI, VTIc, and VTIrrp with number of CP doses and lower Hb. We propose that this phenomenon is likely of multifactorial origin, involving autoregulatory mechanism disturbance. The imaging and measurement of LAD flow velocities are feasible, reliable, and is positively correlated with number of CP doses. Interpretation of postoperative LAD flow velocities should be made in the context of intraoperative events since heart rate, blood pressure, and Hb concentration also influence CA flow parameters.