Differential rates of intravascular uptake and pain perception during lumbosacral epidural injection among adults using a 22-gauge needle versus 25-gauge needle: a randomized clinical trial.

BACKGROUND: Inadvertent intravascular injection has been suggested as the most probable mechanism behind serious neurological complications during transforaminal epidural steroid injections. Authors believe a smaller gauge needle may lead to less intravascular uptake and less pain. Theoretically, there is less chance for a smaller gauge needle to encounter a blood vessel during an injection compared to a larger gauge needle. Studies have also shown smaller gauge needle to cause less pain. The aim of the study was to quantify the difference between a 22-gauge needle and 25-gauge needle during lumbosacral transforaminal epidural steroid injection in regards to intravascular uptake and pain perception. METHODS: This was a prospective single blind randomized clinical trial performed at outpatient spine practice locations of two academic institutions. One hundred sixty-two consecutive patients undergoing lumbosacral transforaminal epidural injections from February 2018 to June 2019 were recruited and randomized to each arm of the study - 84 patients were randomized to the 22-gauge needle arm and 78 patients to 25-gauge arm. Each transforaminal injection level was considered a separate incidence, hence total number of incidence was 249 (136 in 22-gauge arm and 113 in 25-gauge arm). The primary outcome measure was intravascular uptake during live fluoroscopy and/or blood aspiration. The secondary outcome measure was patient reported pain during the procedure on the numerical rating scale. RESULTS: Fisher exact test was used to detect differences between 2 groups in regards to intravascular uptake and paired t-tests were used to detect differences in pain scores. The incidence of intravascular uptake for a 22-gauge needle was 5.9% (95% confidence interval: 1.9 to 9.8%) and for a 25-gauge needle, 7.1% (95% confidence interval: 2.4 to 11.8%) [p = 0.701]. Average numerical rating scale scores during the initial needle entry for 22-gauge and 25-gauge needle was 3.46 (95% confidence interval: 2.94 to 3.98) and 3.13 (95% confidence interval: 2.57 to 3.69) respectively [p = 0.375]. CONCLUSIONS: The study showed no statistically significant difference in intravascular uptake or pain perception between a 22-gauge needle and 25-gauge needle during lumbosacral transforaminal epidural steroid injections. TRIAL REGISTRATION: ClinicalTrials.gov NCT04350307. Registered 4/17/2020. (Retrospectively registered).

Needle-Through-Needle Technique in Lumbar Interlaminar Epidural Steroid Injection: A Case Report.

When performing lumbar epidural steroid injection on obese patients, needle placement can be challenging due to the difficulty in estimating the appropriate needle length to utilize. Often times, the standard 3.5-inch Tuohy needle is too short to reach its target. In our case report, a needle-through-needle technique was attempted in a lumbar interlaminar epidural steroid injection procedure after the initial needle fell short of the epidural space. To avoid removing the initial needle and restarting the procedure using a longer needle, a 20-gauge 6-inch Tuohy needle was inserted into the 17-gauge 3.5-inch Tuohy needle, successfully reaching the epidural space. This technique can facilitate quicker needle placement by avoiding the need for restarting the procedure with a longer needle. Thus, procedural time and radiation exposure may be decreased, as may patient discomfort from repeat needle insertions.

Multicentre clinical simulation evaluation of the ISO 80369-6 neuraxial non-Luer connector.

To avoid potentially fatal wrong-route neuraxial drug errors, international standard ISO 80369-6 specifying a non-Luer neuraxial connector design was published in 2016. We describe usability studies used in development of the design. Thirty-eight doctors and 17 nurses performed simulated procedures on manikins, using devices fitted with Luer connectors or draft ISO 80369-6 'non-Luer' connectors. The procedures included spinal anaesthesia; intrathecal chemotherapy; lumbar puncture, cerebrospinal fluid collection and pressure measurement; epidural catheter placement with bolus injection and critical care use. Participants attempted cross connection between neuraxial connectors and a range of other medical device connectors, including those from the ISO 80369 small-bore connector series. Video recording analysis was used for all assessments. Participants subjectively assessed performance of the draft non-Luer connector, including suitability for routine clinical use. Participants performed 198 procedures. The connector achieved easy, leak-free connections. The willingness of participants to use the non-Luer connectors were: spinal anaesthesia 100%; intrathecal chemotherapy 88%; lumbar puncture, cerebrospinal fluid collection and pressure measurement 93%; epidural catheter placement with bolus injection 78%; critical care use 100%. Concerns raised were generally device related, rather than connector related. Most cross-connection attempts failed, even using above clinical forces and, when successful, were judged of low clinical risk potential; the exception was a malaligned connection between the non-Luer slip and female Luer connectors. This led to revision of the dimensional tolerances of the non-Luer connector to reduce this risk, before publication of the final specification in 2016. We conclude that the ISO 80369-6 neuraxial non-Luer connector is suitable for clinical use.

Epidural test dose in obstetric patients: should we still use it?

PURPOSE OF REVIEW: As the application of a test dose after epidural catheter insertion in obstetrics has recurrently been associated with serious adverse events affecting both maternal and foetal outcomes, the question whether to test or not remains a controversial issue. RECENT FINDINGS: Present guidelines do not provide clear recommendations in this regard and several recent surveys indicate a heterogeneity in clinical routine. SUMMARY: Physiological alterations during pregnancy and labour restrict the use and also the validity of traditional test agents. Epinephrine is not appropriate to detect a vascular insertion in labour and the application of a local anaesthetic test dose may lead to dose-dependent fatal consequences should the catheter be intrathecal, due to an increased sensitivity in parturients. Given the current practice of opioid-amended-low-concentration epidurals, the waiving of a test dose results at worst in a failed epidural, a stark contrast to the potentially severe to fatal complications of a 'traditional' test dose. Hence, an originally preventive measure providing potentially more harm than the consequences of the situation aimed to prevent, should not be recommended. A simple fractionated administration of the initial analgesic dose seems reasonable though.

Cervical Epidural Contrast Spread Patterns in Fluoroscopic Antero-Posterior, Lateral, and Contralateral Oblique View: A Three-Dimensional Analysis.

Objective: To describe and to analyze cervical epidural contrast patterns seen in antero-posterior (AP), contralateral oblique (CLO), and lateral view. To identify factors that might help in predicting contrast distribution pattern and extent. Method: Spread of contrast in the cervical epidural space was prospectively studied in AP, lateral, and three CLO views. Results: CLO view showed contrast spread of variable thickness with its posterior margin overlying the ventral interlaminar line (VILL). In the lateral view, the spread was also of variable thickness, but the posterior margin of the contrast lay on the spinolaminar line in only 10 of 24 patients. Ventral contrast spread was not visualized in any patient. In the AP view, bilateral spread was seen in 14 of 24 subjects, and nerve root spread was seen in 16 of 24 subjects. No association of the pattern of spread or dispersion was seen to patient age, volume injected, or needle location. Conclusions: The CLO view provides a consistent radiological landmark for the posterior margin of contrast in the dorsal epidural space; the lateral view fails to provide such a consistent landmark. The thickness of the spread is variable, both in the CLO and in the lateral view. Thick spread extending into the foramen in the CLO view and over the articular pillars in the lateral view is frequent and should not be misconstrued as subdural or intrathecal spread. In contradistinction to previous studies, true ventral spread was not seen in any patient. When using low volumes, contrast spread is independent of patient age, volume injected, or needle tip location in the AP view.

A New Pressure Guided Management Tool for Epidural Space Detection: Feasibility Assessment on a Simulator.

The detection of epidural space is usually performed by the technique of loss of resistance (LOR) without technological support, although there are few commercial options. We sought to design and develop a new noninvasive system able to detect the LOR without any changes to the conventional procedure. It allows detecting the LOR by a custom made algorithm. The system provides a visual and acoustic feedback when the LOR is detected. We optimized the detection algorithm and investigated the performance of the system during experiments on a custom simulator. During the experiments performed by 10 anesthetists and 10 trainees, the pressure exerted on the syringe plunger was monitored using the custom-made system. Each participant performed four experiments using the system on the simulator. The performance of the system in LOR detection was evaluated comparing the feedback activation and the breaches of the last layer of the simulator. Moreover, each participant filled out a questionnaire to assess how the procedure with the simulator mimics the clinical scenario. A higher questionnaire score corresponds to a more realistic condition (0 = not real, 5 = extremely real). Results showed that the LOR was detected in 74 of the 80 trials (92.5% of the cases); the anesthetists obtained better results than trainees: 97.5 versus 87.5%. The questionnaires showed that all the participants found the trial realistic (score ≥3); anesthetists found it more realistic than trainees (4.2 ± 0.78 vs. 3.8 ± 0.78, mean ± SD). In summary, the proposed system successfully detected the LOR in the large part of the trials. The participants found the trials realistic. A higher success rate was observed in the anesthetists group.

C-Arm Fluoroscope Angle Settings for Fluoroscopically Guided Lumbar Transforaminal Epidural Injections.

BACKGROUND DATA: Minimizing fluoroscopy time in spine interventions is critical for time of procedure as well as radiation safety of the patient and medical personnel. Specific fluoroscopy angle settings for fluoroscopically guided L4-S1 transforaminal epidural injections (TFEIs) have not been described. OBJECTIVES: To describe the most common encountered settings for the C-arm fluoroscope angles for fluoroscopically guided L4-S1 (TFEI). METHODS: Each subject was placed in prone position on a flat fluoroscopy table without utilizing any device to alter innate lumbar spine curvature. The data from 246 consecutive patients at their first encounter in the fluoroscopy suite for a single level subpedicular lumbosacral TFEI was retrospectively analyzed. Most procedures occurred at the L4-5, L5-S1, and S1 levels (227 subjects). The C-arm angles including the oblique, cephalad/caudal were recorded for each subject upon observing final needle positioning for successful completion of the procedure according to ISIS Guidelines. RESULTS: For the L4-5 level, 71% of cases had oblique angle of 30°±5° and 94% of cases had neutral cephalad/caudal tilt (0°±5°) observed. For the L5-S1, 72% of cases had oblique angle of 30°±5° and 62% of cases had cephalad tilt angle of 15°±5° observed. For the S1 level, 73% of cases had oblique angle of 5°±5° and 69% of cases had cephalad tilt angle of 15°±5° observed. DISCUSSION/CONCLUSION: This retrospective descriptive study suggests fluoroscope angles for L4-S1 TFEI as a starting point before fine tuning views accounting for individual anatomy. Angles suggested for each level (oblique/cephalad tilt angles) are as follows: L4-5 (30/0°), L5-S1 (30/15°), and S1 (5/15°). Prospective studies using these guidelines would need to be undertaken to prove reproducibility between interventionalists, time efficiency, and radiation exposure reduction.

Contralateral Oblique View Is Superior to the Lateral View for Lumbar Epidural Access.

OBJECTIVE: The purpose of this study was to perform a comparative analysis of the contralateral oblique (CLO) view and the lateral view for lumbar interlaminar epidural access. DESIGN: After the epidural space was accessed, fluoroscopic images at eight different angles (antero-posterior view, multiple CLO, and lateral view) were prospectively obtained. Visualization and location of needle tip relative to bony landmarks were analyzed. The epidural location of the needle was subsequently confirmed by contrast injection and analysis in multiple views. RESULTS: Visualization of the needle tip and the relevant radiologic landmarks was superior in the CLO view. The needle tip location in the epidural space was most consistent at a CLO angle of 45°. CONCLUSION: This study shows that the CLO view for lumbar interlaminar epidural access offers clear advantages over the lateral view on many clinically important grounds: the needle tip visualization is better, the important radiological landmarks are better visualized, and the needle tip when placed in the epidural space presents a more precise relationship to these landmarks. All of these differences were highly significant. Thus, when using this view, the needle may be directly placed in very close vicinity to the epidural space and true loss of resistance expected soon thereafter. In addition, this view provides the ability to plot the cranio-caudad needle trajectory. The combination of these factors is likely to improve the ease and efficiency of epidural access. The crisp visualization of the final moments of epidural access could also translate to improved safety and accuracy. In light of this, it is suggested that a CLO view at 45° be considered the preferred view for gauging needle depth during interlaminar lumbar epidural access.

Differential Rates of Inadvertent Intravascular Injection during Lumbar Transforaminal Epidural Injections Using Blunt-Tip, Pencil-Point, and Catheter-Extension Needles.

OBJECTIVE: To quantify the incidence of inadvertent vascular penetration during lumbosacral transforaminal epidural injections using blunt-tip, pencil-point, and catheter-extension needles. STUDY DESIGN/SETTING: This is a prospective, observational, consecutive cohort study. SUBJECTS: Two hundred consecutive patients undergoing lumbosacral transforaminal epidural injections at an academic outpatient spine center. METHODS: Four hundred seventy-five fluoroscopically guided lumbosacral transforaminal epidural injections were performed on consecutively consenting patients by one interventional spine physician, using three different needle types. The presence or absence of vascular uptake was determined during contrast injection under live fluoroscopy. RESULTS: Vascular uptake of contrast was observed in 58 of the total 475 injections, for an overall incidence of 12.2%. By needle type, the incidence of inadvertent vascular uptake was 16.6% (26/157) in the pencil-point group, 15.6% (24/154) in the blunt-tip group, and 4.9% (8/164) in the catheter-extension group. The difference in rates is statistically significant between the catheter-extension needle group and both the pencil-point group (P = 0.0009) and blunt-tip group (P = 0.0024). A secondary analysis was performed to quantify the incidence of functional pitfalls between needle groups, with a significantly lower incidence in the pencil-point group compared to both the catheter-extension (P = 0.0148) and blunt-tip needle (P = 0.0288) groups. CONCLUSIONS: Blunt-tip and pencil-point needles have comparable risk of inadvertent vascular injection during lumbosacral transforaminal injections. Catheter-extension needles demonstrated a reduce incidence of vascular uptake, but also result in a significantly higher rate of functional pitfalls that limits their usefulness in routine practice.

A randomised controlled trial using the Epidrum for labour epidurals.

The aim of our study was to determine if using the Epidrum to site epidurals improves success and reduces morbidity. Three hundred parturients requesting epidural analgesia for labour were enrolled. 150 subjects had their epidural sited using Epidrum and 150 using standard technique. We recorded subject demographics, operator experience, number of attempts, Accidental Dural Puncture rate, rate of failure to site epidural catheter, rate of failure of analgesia, Post Dural Puncture Headache and Epidural Blood Patch rates. Failure rate in Epidrum group was 9/150 (6%) vs 0 (0%) in the Control group (P = 0.003). There were four (2.66%) accidental dural punctures in the Epidrum group and none in the Control group (P = 0.060), and 2 epidurals out of 150 (1.33%) in Epidrum group were re-sited, versus 3/150 (2%) in the control group (P = 1.000). The results of our study do not suggest that using Epidrum improves success or reduces morbidity.

Comparison of the Use of Peripheral Nerve Stimulator and Quincke Needle for Lumbar Transforaminal Epidural Steroid Injections.

AIM: To compare the procedural features of transforaminal epidural steroid injection (TFESI) performed using two different needles (Stimuplex® and Quincke) in terms of procedure time, exposed radiation dose and adverse effects and complications, thus providing preliminary data to aid needle selection for TFESI. MATERIAL AND METHODS: Patients who received fluoroscopy-guided single-level lumbosacral TFESI between September 2020 and September 2021 were retrospectively included in this study. The patients were divided into two groups with respect to the needle type used for the procedure ? those treated with a Quincke needle were classified as Group Q and those treated with a Stimuplex® needle comprised Group S. Subsequently, the two groups were compared in terms of their demographic data, procedure time, radiation dose, amount of contrast use, first-hour numeric rating scale (NRS), intravascular flow and complication rates. RESULTS: The number of patients recruited for Groups Q and S was 65 and 61, respectively. No significant difference was observed between the groups regarding their demographic data, preprocedural NRS scores, procedure time, exposed radiation dose and the amount of contrast dye used. Notably, the first-hour NRS scores were found to be significantly lower in Group S (p=0.040) after the procedure. Moreover, the intravascular contrast spread was significantly different between the two groups (p < 0.05) ? it was encountered during four procedures in Group Q, but was altogether absent in Group S. CONCLUSION: The Stimuplex® needle may decrease the possibility of inadvertent intravascular leakages during TFESI and may also improve immediate pain scores after the procedure.

A comparison of Quincke and Whitacre needles with respect to risk of intravascular uptake in S1 transforaminal epidural steroid injections: a randomized trial of 1376 cases.

BACKGROUND: Transforaminal epidural steroid injection (TFESI) is a useful treatment modality for pain management. Most complications of TFESI are minor and transient. However, there is a risk of serious complications such as nerve injury, spinal cord infarct, or paraplegia. Some of the risks are related to direct injury to the vessel or intravascular injection of the particulate steroid. We prospectively tested the hypothesis that the intravascular injection rate of the Whitacre needle is lower than that of the Quincke needle during TFESI. METHODS: This study was a randomized trial of 1376 TFESIs at the S1 level. We collected data of age, gender, height, weight, laterality (right/left), history of lumbosacral spine operation, history of appropriate interval discontinuation of anticoagulation medicines, and underlying disease. During the S1 TFESI, intrasacral bone contact, a blood aspiration test, and real-time fluoroscopy of the intravascular injection using contrast media were investigated. RESULTS: There were no significant differences in the intravascular injection rate with respect to age, gender, height, weight, hypertension, diabetes mellitus, laterality, history of lumbosacral spine operation, or history of appropriate interval discontinuation of anticoagulation medicines. Intravascular injection was significantly associated with a blood aspiration test (P < 0.001), needle tip type (P = 0.002), intrasacral bone contact (P < 0.001), and physicians (some P < 0.05). The use of Quincke needles and intrasacral bone contact increased the rate of intravascular injection. CONCLUSIONS: To reduce the risk of intravascular injection, the use of Whitacre needles without intrasacral bone contact may be a safer and more effective approach.

Simulated evaluation of a non-Luer safety connector system for use in neuraxial procedures.

BACKGROUND: Spinal syringes, needles, and other devices with connectors that will not also connect with Luer devices could substantially reduce wrong-route drug administration errors. This study aimed to evaluate a newly designed non-Luer safety connector system for neuraxial procedures in terms of clinical acceptability and cross-connectivity with conventional Luer devices. METHODS: A non-Luer safety connector system (BD UniVia-6 Safety Connector system), which included non-Luer spinal needles, syringes, and blunt fill filter needles, was evaluated in a prospective, simulated use, randomized study. Clinicians evaluated the acceptability and performance characteristics using a normal saline injectate on an artificial back model. RESULTS: Forty-nine clinicians participated in the study. For 93 of 98 spinal injection procedures, clinicians agreed that overall, the safety system was clinically acceptable (94.9%; 95% lower bound 89.6%). Forty-eight clinicians (98%; 95% lower bound: 90.7%) agreed that the safety system prevented or reduced the risk of misconnection between a conventional syringe and a safety spinal needle. A lower proportion (63.3%; 95% lower bound: 50.5%) agreed that the safety system would prevent or reduce the risk of misconnections between a safety syringe filled with medication intended for spinal injection and an i.v. Luer device. CONCLUSIONS: Our study demonstrated that study clinicians found the safety system to be acceptable with minimal impact on technique in a simulated-use setting. The non-Luer system also appeared to decrease the risk of administration of i.v. medications into the intrathecal space. Further modifications will be required to completely eliminate the risk of administering intrathecal medication i.v. and evaluation in a clinical setting will help determine the true impact of this non-Luer system on patient safety.

An evaluation of contrast medium spread on caudal epidurography with the needle positioned toward the affected side in patients with unilateral lumbosacral radiculopathy.

OBJECTIVE: We used caudal epidurography to compare the spread of contrast medium when the needle was inserted toward the affected side in patients with unilateral radiculopathy undergoing caudal steroid injection. MATERIALS AND METHODS: We enrolled 24 patients with unilateral radiculopathy. A block needle was positioned toward the affected side in the sacral epidural space. After 5 mL of iodinated contrast medium was injected, a standardized anteroposterior view was imaged. Using Adobe Photoshop software, contrast medium spread was assessed by counting pixels within the areas spread on the affected side and on the opposite side, and the pixel counts of the two sides were compared. Spinal nerve root filling was also assessed. RESULTS: The pixel count within the area of contrast medium spread on the side with the needle was significantly greater than that of the opposite side (mean [SD] 41,368.6 [13,143.1] vs 15,165.3 (10,698.1), P < 0.001]. However, 13.6% of the study patients had greater spread on the opposite side. The rates of L5 and S1 nerve root filling in the affected side were 18.2% and 36.4% respectively. CONCLUSIONS: When a needle was intentionally inserted toward the side with radiculopathy, the spread of contrast medium and number of delineated roots tended to be greater on the side with the needle, compared with those on the opposite side. However, the pattern of contrast medium spread in the sacral epidural space varied and some patients even had greater spread on the opposite side.

Epidural contrast flow patterns of transforaminal epidural steroid injections stratified by commonly used final needle-tip position.

OBJECTIVE: To evaluate the relationship between commonly used final needle-tip positions and subsequent contrast flow and patient-reported pain relief in transforaminal epidural steroid injections (TFESIs). DESIGN: Retrospective cross-sectional study. METHODS: Medical records of subjects (N = 83) having undergone a TFESI between January 2008 and January 2009 were reviewed to compare TFESIs using the superior-anterior (SA) vs. the superior-posterior (SP) quadrant. OUTCOME MEASURES: Outcome measures included ventral and dorsal epidural contrast flow as well as near-to-complete pain relief as measured by numerical rating scale pain score pre- and post-procedure. RESULTS: SA TFESIs were associated with greater ventral epidural contrast flow as compared with SP TFESIs (100% vs 61.4%, P < 0.001). SA TFESIs with ventral epidural contrast flow were also associated with flow to a greater number of vertebral levels than SP TFESIs with ventral epidural contrast flow (41% vs 14.8%, P < 0.001). SP TFESIs were associated with greater dorsal epidural contrast flow than SA TFESIs (95.5% vs 43.6%, P < 0.05). SA TFESIs were also associated with a larger proportion of patients who achieved near-to-complete pain relief (P < 0.05) and greater reduction than SP TFESIs in post-procedure pain score relative to pre-procedure (3.3 vs 1.5, P < 0.01). DISCUSSION: The evolution of TFESIs must balance both safety and efficacy. The efficacy of SA TFESIs is demonstrated to be superior to that of SP TFESIs with regards to ventral epidural flow and patient-reported pain relief. Further efforts should focus on demonstrating efficacy while optimizing safety.