A Coaxial Dual-element Focused Ultrasound Probe for Guidance of Epidural Catheterization: An Experimental Study

Ultrasound guidance for epidural block has improved clinical blind-trial problems but the design of present ultrasonic probes poses operating difficulty of ultrasound-guided catheterization, increasing the failure rate. The purpose of this study was to develop a novel ultrasonic probe to avoid needle contact with vertebral bone during epidural catheterization. The probe has a central circular passage for needle insertion. Two focused annular transducers are deployed around the passage for on-axis guidance. A 17-gauge insulated Tuohy needle containing the self-developed fiber-optic–modified stylet was inserted into the back of the anesthetized pig, in the lumbar region under the guidance of our ultrasonic probe. The inner transducer of the probe detected the shallow echo signals of the peak-peak amplitude of 2.8 V over L3 at the depth of 2.4 cm, and the amplitude was decreased to 0.8 V directly over the L3 to L4 interspace. The outer transducer could detect the echoes from the deeper bone at the depth of 4.5 cm, which did not appear for the inner transducer. The operator tilted the probe slightly in left-right and cranial-caudal directions until the echoes at the depth of 4.5 cm disappeared, and the epidural needle was inserted through the central passage of the probe. The needle was advanced and stopped when the epidural space was identified by optical technique. The needle passed without bone contact. Designs of the hollow probe for needle pass and dual transducers with different focal lengths for detection of shallow and deep vertebrae may benefit operation, bone/nonbone identification, and cost.

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Eyes in the Needle

Anesthesiology ◽

10.1097/aln.0b013e31821b5746 ◽

2011 ◽

Vol 114 (6) ◽

pp. 1320-1324 ◽

Cited By ~ 25

Author(s):

Huihua K. Chiang ◽

Qifa Zhou ◽

M. Susan Mandell ◽

Mei-Yung Tsou ◽

Shih-Pin Lin ◽

...

Keyword(s):

Epidural Catheter ◽

Dura Mater ◽

Epidural Space ◽

Dural Puncture ◽

Ligamentum Flavum ◽

Needle Insertion ◽

Epidural Needle ◽

Average Weight ◽

Ultrasound Probe ◽

Epidural Catheters

Background Epidural needle insertion is usually a blind technique where the rate of adverse events depends on the experience of the operator. A novel ultrasound method to guide epidural catheter insertion is described. Methods An ultrasound transducer (40 MHz, a -6 dB fractional bandwidth of 50%) was placed into the hollow chamber of an 18-gauge Tuohy needle. The single crystal was polished to a thickness of 50 μm, with a width of 0.5 mm. Tissue planes were identified from the reflected signals in an A-mode display. The device was inserted three times into both the lumbar and thoracic regions of five pigs (average weight, 20 kg) using a paramedian approach at an angle of 35-40°. The epidural space was identified using signals from the ligamentum flavum and dura mater. Epidural catheters were placed with each attempt and placement confirmed by contrast injection. Results The ligamentum flavum was identified in 83.3% of insertions and the dura mater in all insertions. The dura mater signal was stronger than that of the ligamentum flavum and served as a landmark in all epidural catheter insertions. Contrast studies confirmed correct placement of the catheter in the epidural space of all study animals. Conclusions This is the first study to introduce a new ultrasound probe embedded in a standard epidural needle. It is anticipated that this technique could reduce failed epidural blocks and complications caused by dural puncture.

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Changes in Gaze Behavior during the Learning of the Epidural Technique with a Simulator in Anesthesia Novices (Preprint)

10.2196/preprints.20058 ◽

2020 ◽

Author(s):

Emanuele Capogna ◽

Francesco Salvi ◽

Lorena Delvino ◽

Andrea Di Giacinto ◽

Angelica Del Vecchio ◽

...

Keyword(s):

Eye Tracking ◽

Assessment Tool ◽

Objective Assessment ◽

Needle Insertion ◽

Epidural Block ◽

Epidural Needle ◽

Eye Tracker ◽

Gaze Behavior ◽

Before And After ◽

Potential Applications

BACKGROUND Current literature demonstrates the ability of eye tracking to provide reliable quantitative data as an objective assessment tool, with potential applications to medical and surgical training to improve performance. OBJECTIVE The aim of this study was to evaluate the changes in gaze behavior in anesthesia novice trainees when performing a simulated epidural technique before and after a hands-on training on the epidural simulator. METHODS We enrolled 48 novice trainees who had never previously performed an epidural block. After a standardized learning module, each trainee practiced the epidural procedure on the epidural simulator while wearing a pair of eye tracking glasses (Tobii Pro Glasses 50 Hz wearable wireless eye tracker). After this baseline recording, each trainee spent two hours practicing with the epidural simulator and afterwards once again performed the eye tracking epidural procedure. Eye tracking metrics and epidural learning (duration of the procedure and number of attempts) before and after the simulated practice were recorded. RESULTS The duration of the epidural procedure was shorter and the number of epidural attempts reduced after the tutorial. Before the tutorial, during needle insertion. the eye tracking metrics showed more visit counts of shorter duration and after the tutorial less visit counts (P=.05) but of longer duration (P=.03). A significant correlation was observed between the number of epidural needle insertions (additional attempts) and the number (OR=2.02 (0.23-1.27; P=.008)) and duration (OR=0.65 (-0.93-0.02; P=.05)) of visits. CONCLUSIONS In novice anesthesia trainees who had never previously performed an epidural block, we observed significant changes in gaze behavior associated with increased performance during the initial phase of epidural technique learning with a simulator. These results may create a prototype for future studies on eye tracking technique as a teaching and evaluating tool in simulation. CLINICALTRIAL Not necessary

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Cephalic Angulation of Epidural Needle Insertion may be an Important Factor to Safely Approach the Epidural Space: A Mathematical Model

Brazilian Journal of Anesthesiology (English Edition) ◽

10.1016/j.bjane.2012.07.010 ◽

2013 ◽

Vol 63 (4) ◽

pp. 375

Author(s):

Karl Otto Geier

Keyword(s):

Mathematical Model ◽

Epidural Space ◽

Needle Insertion ◽

Epidural Needle

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Epidural needle insertion

Der Anaesthesist ◽

10.1007/s00101-018-0499-1 ◽

2018 ◽

Vol 67 (12) ◽

pp. 922-930 ◽

Cited By ~ 2

Author(s):

H. Bomberg ◽

N. Paquet ◽

A. Huth ◽

S. Wagenpfeil ◽

P. Kessler ◽

...

Keyword(s):

Needle Insertion ◽

Epidural Needle

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Reliability and Safety of Contra-Lateral Oblique View for Interlaminar Epidural Needle Placement

January 2018 - Pain Physician ◽

10.36076/ppj.2017.1.e65 ◽

2018 ◽

Vol 1 (21;1) ◽

pp. E65-E73

Author(s):

Richard Derby

Keyword(s):

Epidural Space ◽

Ligamentum Flavum ◽

Case Series ◽

Senior Author ◽

Epidural Block ◽

Observer Agreement ◽

Epidural Needle ◽

Oblique View ◽

Fluoroscopic Imaging

Cord trauma is a risk with a cervical and thoracic interlaminar epidural approach to the epidural space. Intermittent lateral fluoroscopic imaging to detect needle depth is often cumbersome and may be difficult to interpret. In comparison, the contra-lateral oblique (CLO) fluoroscopic view is efficient and easy to interpret. However, the in vivo reliability and safety of this technique has not been formally investigated. The senior author collected fluoroscopic images on 278 consecutive patients undergoing an interlaminar epidural block at the T1-T2 level performed using a 17 gauge Tuohy needle. Before catheter placement, anterior-posterior (AP) and CLO fluoroscopic images were saved with the needle at the ligamentum flavum and the needle just through the ligamentum flavum. We randomly selected the images of 40 cases that included the paired CLO images (total 80 images) documenting the views at and through the ligamentum flavum. Three interventionalists were asked to review, in a blinded fashion, the randomly selected, paired CLO images and to score each image, recording whether the 17 gauge needle was in or out of the epidural space to determine the accuracy and reliability of this technique. There was a 97.5%, 95%, and 93.8% agreement between each reviewing physician and the senior author resulting in a correlation using the Kappa statistic value of 0.950, 0.875, and 0.874, respectively (P < 0.001). The 3 reviewing physicians disagreed with the senior author’s correct answer in 2.5%, 5%, and 6.2%, respectively, however, the disagreement occurred primarily because of poor image quality. Agreement between the 3 reviewing physicians was 93.8%, 96.3%, and 90%, with a Kappa value of 0.875, 0.924, and 0.799, respectively (P < 0.001). There was 100% technical success in the 278 case series without “wet taps,” provocation of pain during entry, or any other immediate post procedural complication. We conclude the CLO view provides an efficient and reliable method to visualize needle tip depth in relation to the epidural space. The close inter-observer agreement was possible with minimal physician instruction. Key words: Cervical interlaminar, cervical epidural, contra-lateral oblique, fluoroscopic imaging

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A Novel Introducer for Ultrasound-Guided Cryoneurolysis Administration to Improve Patient Safety an d Functionality

Pain Management Case Reports ◽

10.36076/pmcr.2020/4/217 ◽

2020 ◽

pp. 217-220

Author(s):

JOhn J. Finneran IV

Keyword(s):

Peripheral Nerve ◽

Postoperative Analgesia ◽

Local Anesthetic ◽

Improve Patient Safety ◽

Femoral Nerve ◽

Needle Insertion ◽

Ultrasound Guided ◽

Needle Pass ◽

Time Required ◽

Local Anesthetic Injection

Background: Percutaneous cryoneurolysis provides prolonged postoperative analgesia by placing a probe adjacent to a peripheral nerve and cooling the probe tip, inducing a reversible block that lasts weeks to months. Unfortunately, freezing the nerve can produce significant pain. Consequently, local anesthetic is generally applied to the nerve prior to cryoneurolysis, which, until now, required an additional needle insertion increasing both the risks and duration of the procedure. Case Presentation: Three patients underwent ultrasound-guided percutaneous cryoneurolysis of either the sciatic and saphenous nerves or the femoral nerve. In all patients, the local anesthetic injection and cryoneurolysis were accomplished with a single needle pass using the novel probe introducer. Conclusion: This introducer allows perineural local anesthetic injection followed immediately by cryoneurolysis, thereby sparing patients a second skin puncture, lowering the risks of the procedure, and decreasing the overall time required for cryoneurolysis. Key words: Cryoablation, cryoanalgesia, peripheral nerve block, postoperative analgesia, ultrasound

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EMLA Cream Prior to Insertion of Elective Epidurals

Anaesthesia and Intensive Care ◽

10.1177/0310057x9502300311 ◽

1995 ◽

Vol 23 (3) ◽

pp. 339-341 ◽

Cited By ~ 10

Author(s):

J. A. Elson ◽

M. J. Paech

Keyword(s):

Elective Caesarean Section ◽

Needle Insertion ◽

Patient Comfort ◽

Epidural Needle ◽

Double Blind Study ◽

Double Blind ◽

Emla Cream ◽

Skin Infiltration ◽

Group A ◽

Group B

A randomized double-blind study was conducted in 83 women scheduled for elective caesarean section to determine the efficacy of EMLA and lignocaine infiltration for epidural insertion. The patients were randomly allocated to one of three groups: Group A (EM/LIG) received EMLA and intradermal and subdermal 1% lignocaine infiltration, Group B (EM/SAL) EMLA and saline while Group C (PL/LIG) received placebo cream and 1% lignocaine. Assessments using a 100 mm pain score were performed on skin infiltration and after subsequent insertion of a 16 gauge Tuohy needle into the supraspinous ligament. Skin changes under the applied cream and nursing rating of patients’ response were also noted. Statistical analyses were performed using Kruskal-Wallis and Fisher's Exact Tests. Groups were comparable for age, weight, parity and EMLA application time (interquartile range 105-150 minutes) There were significantly higher pain scores for skin infiltration in Group C (PL/LIG) (P<0.01) and for epidural needle insertion in Group B (EM/SAL) (P<0.05). We concluded that in this patient population, the application of EMLA cream for at least 90 minutes plus 1% lignocaine infiltration optimized patient comfort for epidural insertion.

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Real-time Ultrasound-Guided Lumbar Epidural with Transverse Interlaminar View: Evaluation of an In-Plane Technique

Pain Medicine ◽

10.1093/pm/pnz026 ◽

2019 ◽

Vol 20 (9) ◽

pp. 1750-1755 ◽

Cited By ~ 2

Author(s):

Hesham Elsharkawy ◽

Wael Saasouh ◽

Rovnat Babazade ◽

Loran Mounir Soliman ◽

Jean-Louis Horn ◽

...

Keyword(s):

Success Rate ◽

Real Time ◽

Epidural Anesthesia ◽

Needle Insertion ◽

Adult Patients ◽

Epidural Needle ◽

Anatomical Landmarks ◽

Care Hospital ◽

Open Prostatectomy ◽

Ultrasound Guided

Abstract Objective The anatomical landmarks method is currently the most widely used technique for epidural needle insertion and is faced with multiple difficulties in certain patient populations. Real-time ultrasound guidance has been recently used to aid in epidural needle insertion, with promising results. Our aim was to test the feasibility, success rate, and satisfaction associated with a novel real-time ultrasound-guided lumbar epidural needle insertion in the transverse interlaminar view. Design Prospective descriptive trial on a novel approach. Setting Operating room and preoperative holding area at a tertiary care hospital. Subjects Adult patients presenting for elective open prostatectomy and planned for surgical epidural anesthesia. Methods Consented adult patients aged 30–80 years scheduled for open prostatectomy under epidural anesthesia were enrolled. Exclusion criteria included allergy to local anesthetics, infection at the needle insertion site, coagulopathy, and patient refusal. A curvilinear low-frequency (2–5 MHz) ultrasound probe and echogenic 17-G Tuohy needles were used by one of three attending anesthesiologists. Feasibility of epidural insertion was defined as a 90% success rate within 10 minutes. Results Twenty-two patients were enrolled into the trial, 14 (63.6%) of whom found the process to be satisfactory or very satisfactory. The median time to perform the block was around 4.5 minutes, with an estimated success rate of 95%. No complications related to the epidural block were observed over the 48 hours after the procedure. Conclusions We demonstrate the feasibility of a novel real-time ultrasound-guided epidural with transverse interlaminar view.

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