Simultaneous Measurement of Multiple Parameters of a Subwavelength Structure Based on the Weak Value Formalism.

A mathematical extension of the weak value formalism to the simultaneous measurement of multiple parameters is presented in the context of an optical focused vector beam scatterometry experiment. In this example, preselection and postselection are achieved via spatially varying polarization control, which can be tailored to optimize the sensitivity to parameter variations. Initial experiments for the two-parameter case demonstrate that this method can be used to measure physical parameters with resolutions at least 1000 times smaller than the wavelength of illumination.

Effect of Nerve Stimulation Use on the Success Rate of Ultrasound-Guided Subsartorial Saphenous Nerve Block: A Randomized Controlled Trial.

Background And Objectives: Ultrasound-guided subsartorial saphenous nerve block is commonly used to provide complete surgical anesthesia of the foot and ankle in combination with a popliteal sciatic nerve block. However, in part owing to its small caliber and absence of a prominent vascular landmark in the subsartorial plane distal to the adductor canal, the saphenous nerve is more difficult to reliably block than the sciatic nerve in the popliteal fossa. Although the saphenous nerve is a sensory nerve only, neurostimulation can be used to elicit a "tapping" sensation on the anteromedial aspect of the lower leg extending toward the medial malleolus.

Regional Versus General Anesthesia and the Incidence of Unplanned Health Care Resource Utilization for Postoperative Pain After Wrist Fracture Surgery: Results From a Retrospective Quality Improvement Project.

Background And Objectives: The establishment at our center of a dedicated regional anesthesia service in 2008-2009 has resulted in a marked increase in single-shot brachial plexus blocks (sBPBs) for ambulatory wrist fracture surgery. Despite the documented benefits of regional over general anesthesia (GA), there has been a perceived increase among sBPB patients in postoperative return rates for pain at our institution. We conducted a retrospective quality improvement project to examine this.

Ultrasound guidance versus direct palpation for radial artery catheterization by expert operators: a randomized trial among Canadian cardiac anesthesiologists.

Purpose: The use of ultrasound (US) for radial arterial catheterization has been reported to result in faster insertion times with fewer complications when compared with traditional direct palpation (DP). We sought to determine if this applies to expert operators and tested the hypothesis that, among cardiac anesthesiologists, US-guided insertion similarly results in faster insertion times as well as fewer re-directs, attempts, and complications.

Methods: Following Research Ethics Board Approval, we conducted a randomized clinical trial in 125 patients scheduled for cardiac surgery at a single tertiary/quaternary care centre.

Hemidiaphragmatic paralysis following ultrasound-guided supraclavicular versus infraclavicular brachial plexus blockade: a randomized clinical trial.

Background And Objectives: The comparative incidences of hemidiaphragmatic paralysis associated with contemporary ultrasound-guided supraclavicular versus infraclavicular blockade have not received extensive study. We tested the hypothesis that the infraclavicular approach results in a lower incidence of hemidiaphragmatic paralysis compared with supraclavicular blockade when a standard local anesthetic volume and concentration are used.

Methods: With institutional human ethics board approval, we enrolled 64 patients undergoing right-sided upper extremity surgery in a randomized, blinded, parallel-group trial.

Ultrasound-guided saphenous nerve block--within versus distal to the adductor canal: a proof-of-principle randomized trial.

Purpose: Reliable saphenous nerve blockade is a desirable complement to popliteal sciatic nerve blockade for foot and ankle surgery. We compared two promising ultrasound-guided techniques, the supine adductor canal (AC) technique and the prone peri-saphenous branch of the descending genicular artery (Peri-SBDGA) technique, using 8 mL of 2% lidocaine with epinephrine 1:400,000.

Methods: Following Research Ethics Board approval, we conducted a randomized single-blinded parallel-group trial in 102 patients undergoing foot and ankle surgery at a single centre.

A regional anesthesia-based "swing" operating room model reduces non-operative time in a mixed orthopedic inpatient/outpatient population.

Purpose: We recently reported on the efficacy of a new "swing" room model involving two alternating ORs and regional anesthesia in increasing operating room (OR) throughput in a dedicated ambulatory orthopedic surgery facility. The purpose of this study was to evaluate this model in a main OR suite setting with typical mixed inpatient/outpatient cases.

Methods: We conducted a retrospective matched-pair cohort study of 133 upper extremity surgery patients treated in the swing room model under ultrasound-guided brachial plexus blockade.

A "swing room" model based on regional anesthesia reduces turnover time and increases case throughput.

Purpose: Our centre recently implemented a new ambulatory care model featuring two alternate regional anesthesia "swing" operating rooms (RA-SRs) managed by a single anesthesiologist. We hypothesized that this model would be associated with decreased turnover times and improved recovery profiles when compared with a traditional model with a single operating room using general anesthesia.

Methods: We conducted a retrospective cohort study of 164 patients scheduled for hand and wrist surgery who were treated in the RA-SRs under brachial plexus blockade, and we compared the findings with a matched historical control group of patients who underwent general anesthesia in a single operating room (GA-OR).

Infusate contamination in regional anesthesia: what every anesthesiologist should know.

Infection can be a devastating complication of regional anesthesia. Contaminated infusate as a cause of infection in neuraxial anesthesia or peripheral nerve blockade has rarely been reported in the literature. However, it may be an important source of morbidity, especially as increasing numbers of patients are being discharged with perineural catheters and portable pumps of local anesthetic, which may infuse for several days at home.

Adherence and acceptability of once daily Lamivudine and abacavir in human immunodeficiency virus type-1 infected children.

Background: Data on adherence to and acceptability of once daily lamivudine and abacavir are few.

Methods: Twenty-four U.K.