Publications by authors named "Michael J Fredrickson"

Background And Objectives: Ultrasound guidance reduces the required local anesthetic volume for successful peripheral nerve block, but it is unclear whether this influences block duration. We investigated the ropivacaine volume and concentration effect on interscalene block duration.

Methods: One hundred eighty-five patients were randomized to 5 ropivacaine volume/concentration combinations (0.

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Optimizing evidence-based medicine--and therefore the care of our patients--requires a public record of both the benefits and the risks of various medical interventions. Unfortunately, available evidence is often skewed because some clinical trials are withheld from publication; only selected data are reported, and statistical techniques are often inappropriately determined following data analysis. Prospective clinical trial registration (PCTR) is the public documentation of trial protocols--today primarily on the Internet--before data analysis (and ideally before trial commencement).

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Background And Objectives: We investigated perineural catheter threading distance and orifice configuration during continuous interscalene analgesia.

Methods: One hundred fifty-three patients receiving an anterolateral interscalene catheter (catheter needle and nerve/plexus in a similar alignment) for elective shoulder surgery were randomized to 1 of 3 groups: following out-of-plane ultrasound confirmation of the needle tip immediately lateral to the C5/6 roots, a nonstimulating catheter was blindly advanced 0.5 cm (end-hole; n = 50), 2.

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Background And Objectives: Ultrasound guidance reduces the required local anesthetic volume for successful peripheral nerve blockade, but it is unclear whether this impacts postoperative analgesia. This prospective, randomized, observer-blinded study tested the hypothesis that a low-volume ultrasound-guided ankle block would provide similar analgesia after foot surgery compared with a conventional-volume surface landmark technique.

Methods: A total of 72 patients presenting for elective foot surgery under general anesthesia were randomized to receive a low-volume ultrasound-guided ankle block (n = 37; ropivacaine 0.

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Background And Objectives: Two distinctly different approaches to interscalene catheter placement have been in common use for close to a decade. This prospective randomized study tested the hypothesis that interscalene catheters placed using the posterior approach would provide a more effective analgesia after shoulder surgery compared with catheters placed using the anterolateral approach.

Methods: A total of 110 patients presenting for elective shoulder surgery were randomly assigned to receive an ultrasound-guided posterior (n=54) or anterolateral (n=56) interscalene catheter with 20 mL of ropivacaine 0.

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Background: Ultrasound-guided transversus abdominis plane (TAP) block has shown promise for analgesia after pediatric inguinal surgery. This prospective, randomized study tested the hypothesis that the TAP block would provide comparable analgesia after pediatric inguinal surgery compared with a conventional ultrasound-guided ilioinguinal block.

Methods: After induction of general anesthesia, infants and children presenting for elective inguinal surgery were randomly assigned to receive an ultrasound-guided TAP block (needle cephalad of the iliac crest at the anterior axillary line) (n = 20) or ilioinguinal block (needle immediately anteromedial to the anterior superior iliac spine) (n = 21).

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Background: The optimal site for local anesthetic placement during ultrasound-guided infraclavicular block remains controversial.

Methods: Patients were randomized to receive lidocaine 2% 30 mL as a single injection posterior to the axillary artery (n = 51) or a triple injection ideally adjacent to each brachial plexus cord (n = 49). Pinprick sensory and motor block (3 = no block, 0 = complete block) were assessed to 20 minutes in the 4 distal nerve territories.

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Background: This three-staged study estimated the volume and concentration of interscalene ropivacaine that would prevent recovery room pain after shoulder surgery under general anesthesia.

Methods: Stages 1/2: Interscalene catheter administration of ropivacaine was by a 10% incremental up-down sequential manner depending on the presence of recovery room pain in the previous patient. Stage 1: Ropivacaine (0.

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Background And Objectives: The utility of continuous perineural infusions for lesser painful shoulder procedures is not well established. We hypothesized that the addition of a continuous interscalene ropivacaine infusion to a single-injection interscalene block would improve analgesia after minor arthroscopic shoulder surgery.

Methods: An ultrasound-guided interscalene catheter targeting the C5-C6 roots/superior trunk was placed preoperatively in patients undergoing arthroscopic subacromial decompression, excision lateral clavicle, or stabilization.

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Background And Objectives: Ultrasound (US) imaging facilitates catheter placement adjacent to the most appropriate elements of the brachial plexus, which for shoulder surgery are the C5YC6 roots or superior trunk. Therefore, it was investigated whether such placement would improve catheter effectiveness compared to placement with traditional techniques.

Methods: Needles introduced for catheter insertion were prospectively randomized to either US guidance immediately lateral to the C5-C6 roots/superior middle trunks (n = 43) or neurostimulation (NS) guidance to an appropriate motor response at less than 0.

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Purpose: Recent reports of painless intraneural injection of low volumes of local anesthetic without subsequent neurological deficit have led to the suggestion that deliberate subepineural injection may be a safe and therefore acceptable practice.

Clinical Features: This report describes a case where a venous cannulation needle inadvertently penetrated a patient's median nerve. Sudden onset severe lancinating pain occurred in the median nerve sensory distribution.

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Background: In this prospective, randomized study, we tested the hypothesis that interscalene catheters placed for shoulder surgery using an ultrasound needle end point provide postoperative analgesia similar in quality to those placed using a neurostimulation needle end point. Secondary end points included needle time under the skin, procedure-related pain, and the incidence of early neurological complications.

Methods: Patients presenting for shoulder surgery were recruited.

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Background And Objectives: Neurostimulation during single shot interscalene block has a significant false negative motor response rate. Compared with tangential needle approaches for single shot block, interscalene catheter (ISC) placement commonly involves Tuohy needles inserted longitudinally to the brachial plexus. This study aimed to determine the sensitivity of neurostimulation during ultrasound-guided ISC needle placement, and the feasibility of an ultrasound-guided ISC needle endpoint.

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Background And Objectives: Large prospective studies evaluating continuous interscalene block for shoulder surgery have thus far been limited to inpatient and university teaching practices. Shoulder surgery is increasingly being performed on an outpatient basis. The aim of this case series was to prospectively evaluate a large series of interscalene catheters for ambulatory shoulder surgery in a private practice setting.

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