Technical guideline for intra-prepontine cisternal drug delivery via spinal puncture through subarachnoid catheterization. / ç»è„ŠæŸ±æ¤Žé—´éš™ç©¿åˆºè››ç½‘è†œä¸‹è ”è„‘æ¡¥å‰æ± ç½®ç®¡è¯ç‰©è¾“æ³¨æŠ€æœ¯åº”ç”¨æŒ‡å—.

OBJECTIVES: The distribution characteristics of intrathecal drugs and the limitation of current catheterization techniques make traditional intrathecal analgesic treatment nearly useless for refractory craniofacial pain, such as trigemina neuralgia. This technical guideline aims to promote the widespread and standardize the application of intra-prepontine cisternal drug delivery via spinal puncture and catheterization. METHODS: A modified Delphi approach was used to work for this guideline. On the issues related to the intra-prepontine cisternal targeted drug delivery technique, the working group consulted 10 experts from the field with 3 rounds of email feedback and 3 rounds of conference discussion. RESULTS: For the efficacy and safety of the intra-prepontine cisternal targeted drug delivery technique, a consensus was formed on 7 topics (with an agreement rate of more than 80%), including the principles of the technique, indications and contraindications, patient preparation, surgical specifications for intra-prepontine cisternal catheter placement, analgesic dosage coordination, analgesic management, and prevention and treatment of complications. CONCLUSIONS: Utilizing the intra-prepontine cisternal drug infusion system to manage refractory craniofacial pain could provide advantages in terms of minimally invasive, secure, and effective treatment. This application can not only alleviate the suffering of individuals experiencing the prolonged pain but also support the maintenance of quality of life and dignity in their final moments, justifiing its widespread dissemination and standardized adoption in domestic and international professional fields.

Delayed-Onset Idiopathic Intracranial Hypertension After Liposuction: A Case Report and Review.

ABSTRACT: Although systemic complications following liposuction are rare, visual impairment has been reported in a few cases and may occur for a variety of reasons. Here we present the case of a 31-year-old woman who underwent 360° liposuction and subsequently developed headaches and delayed partial visual disturbance 10 days after the procedure. She had symptoms suggestive of idiopathic intracranial hypertension, which was confirmed by lumbar puncture. A literature search revealed other case reports of visual changes or headaches following high-volume liposuction. Our case provides further evidence of a rare association between liposuction and idiopathic intracranial hypertension, emphasizing the need for thorough preoperative evaluations and the consideration of possible risks.

Full-Endoscopic Foraminoplasty and Lumbar Discectomy for Single-Level Lumbar Disc Herniation.

The Transforaminal Endoscopic Surgical System (TESSYS) technique has gained popularity for the treatment of lumbar disc herniations. Foraminoplasty is the key procedure in TESSYS. However, it requires advanced skills and long-term learning, which hinder its widespread adoption among surgeons. Recently, the introduction of full-endoscopic solutions has made the process more manageable. The main difference from traditional single-portal endoscopic surgery is that full-endoscopic surgery is equipped with a larger working channel, allowing full visualization of foraminoplasty and decreasing reliance on intraoperative fluoroscopy. Recently, published studies have shown that full-endoscopic foraminoplasty and lumbar discectomy (FEFLD) could achieve comparable results to conventional microdiscectomy in terms of pain relief and functional outcomes, while enhancing postoperative recovery. This study describes the technique of FEFLD in detail, including every crucial step, such as patient positioning, puncture trajectory, endoscopic dissection of the superior articular process (SAP), endoscopic foraminoplasty, and more. We hope this will be helpful to beginners who wish to apply this approach.

[Possibilities of dynamic phase contrast MRI of cerebrospinal fluid for performing a tap test in a patient with idiopathic normotensive hydrocephalus]. / Vozmozhnosti dinamicheskoi fazovo-kontrastnoi MR-likvorografii pri vypolnenii tap-testa u patsienta s idiopaticheskoi normotenzivnoi gidrotsefaliei.

Idiopathic normotensive hydrocephalus (iNH) is a widespread disease in elderly patients. The effectiveness of iNG treatment and the subsequent quality of patients' lives directly depends on timely and early diagnosis. The criteria for diagnosing iNG that are used in neuroimaging can also be found in patients without clinical manifestations of this disease, and the widely used tap-test is an invasive technique with a rather low sensitivity. The need for early diagnosis and initiation of treatment before the development of irreversible damage to brain structures determines the relevance of the search for an accessible, minimally invasive, accurate and safe diagnostic method. The article presents a clinical observation of the use of phase-contrast MRI of cerebrospinal fluid (CSF) in a female patient with a positive response to the tap test with a quantitative analysis of changes in CSF flow parameters and ALVI and Evans indices depending on the time after CSF evacuation. Phase-contrast MRI of CSF with a quantitative assessment of CSF flow parameters in combination with an assessment of the ALVI index has the potential to increase the accuracy of diagnosing iNH and is of scientific interest for further research.

The Incidence of Postoperative Complications Following Lumbar and Bone Marrow Punctures in Pediatric Anesthesia: Insights From APRICOT.

OBJECTIVE: Bone marrow aspiration and lumbar puncture are procedures frequently performed in pediatric oncology. We aimed at assessing the incidence and risk factors of perioperative complications in children undergoing these procedures under sedation or general anesthesia. METHODS: Based on the APRICOT study, we performed a secondary analysis, including 893 children undergoing bone marrow aspiration and lumbar puncture. The primary outcome was the incidence of perioperative complications. Secondary outcomes were their risk factors. RESULTS: We analyzed data of 893 children who underwent 915 procedures. The incidence of severe adverse events was 1.7% and of respiratory complications was 1.1%. Prematurity (RR 4.976; 95% CI 1.097-22.568; P = 0.038), intubation (RR: 6.80, 95% CI 1.66-27.7; P =0.008), and emergency situations (RR 3.99; 95% CI 1.14-13.96; P = 0.030) increased the risk for respiratory complications. The incidence of cardiovascular instability was 0.4%, with premedication as risk factor (RR 6.678; 95% CI 1.325-33.644; P =0.021). CONCLUSION: A low incidence of perioperative adverse events was observed in children undergoing bone marrow aspiration or lumbar puncture under sedation and/or general anesthesia, with respiratory complications being the most frequent. Careful preoperative assessment should be undertaken to identify risk factors associated with an increased risk, allowing for appropriate adjustment of anesthesia management.

Ultrasound-Assisted Lumbar Punctures in Children: An Updated Systematic Review With Meta-Analysis.

CONTEXT: Lumbar puncture (LP) is a common procedure in children, but the rates of unsuccessful and traumatic LPs remain high. Point-of-care ultrasound (POCUS) has been proposed as a tool for improvement. OBJECTIVES: Our aim was to systematically review current evidence on the usefulness of POCUS assisted LP in children. DATA SOURCES: PubMed, Embase, and the CENTRAL were searched up to November 2022. STUDY SELECTION: We searched for randomized control trials assessing the effectiveness of POCUS assisted LP in children. DATA EXTRACTION: Data were extracted by 2 reviewers independently. RESULTS: Seven randomized control trials involving 618 participants were included. Overall, the first attempt POCUS assisted LP was successful in 72% compared with 59.6% in the standard group, regardless of the definition used. The calculated risk difference was 13.0% (95% confidence interval [CI]: 3% to 23%) I2:53%, odds ratio: 2.00 (95% CI: 1.13 to 3.53), I2: 45% and risk ratio:1.21 (95% CI: 1.01 to 1.44) I2:64%. Additionally, fewer traumatic LPs occurred in the US-assisted group, with a risk difference of -12% (95% CI: -0.22 to -0.03), odds ratio: 0.45 (95% CI: 0.26 to 0.78) and risk ratio: 0.53 (95% CI: 0.35 to 0.79). POCUS did not extend the duration of LP procedure with mean difference: -1.11 (95% CI: -2.88 to 0.66). CONCLUSIONS: POCUS improved the first attempt success rate and reduced the incidence of traumatic LPs compared with standard LP procedure in children. Therefore, if it is available, POCUS should be used routinely before every LP, especially when performed by less experienced physicians.

Computerised modified paramedian approach technique versus conventional midline approach technique of lumbar puncture: a randomised control trial protocol.

INTRODUCTION: The lumbar puncture (LP) technique is widely used for diagnostic and therapeutic purposes. In recent years, the paramedian approach technique (PAT) has gained increasing interest due to its advantages over the conventional midline approach technique (MAT) that has been traditionally employed in clinical practice for LP. However, there have been inconsistent discussions regarding the efficacy of different LP techniques. Based on digital virtual human and computer simulation techniques, a new approach called computerised modified PAT (CMPAT) was proposed. Therefore, the aim of this study is to discuss a randomised controlled trial (RCT) protocol to investigate and compare the effects of CMPAT and MAT in patients undergoing LP. METHODS AND ANALYSIS: We will conduct a prospective, multicentre RCT. The study will recruit 84 patients aged 18-99 years who require LP. Participants will be randomly assigned to either the CMPAT treatment group (group A) or the MAT treatment group (group B). The primary outcome measure will be the number of needle insertion attempts required for a successful LP. Secondary outcomes will include the puncture success rate, pain assessment in the back, head, and legs, and the occurrence of complications. The measurement of these secondary outcomes will be taken during the procedure, as well as at specific time points: 30 min, 6 hours, 1 day, 3 days, 7 days, 2 weeks and 4 weeks after the procedure. Pain levels will be assessed using a Numerical Rating Scale. ETHICS AND DISSEMINATION: Ethical approval (2022YF052-01) has been obtained from the Ethics Committee of Fujian Medical University Union Hospital, Fuzhou, China. The research findings will be published in an international peer-reviewed scientific journal and presented at scientific conferences. TRIAL REGISTRATION NUMBER: ChiCTR2300067937.

Clinical improvements in temporospatial gait variables after a spinal tap test in individuals with idiopathic normal pressure hydrocephalus.

Idiopathic Normal Pressure Hydrocephalus (iNPH) is a neurological condition that often presents gait disturbance in the early stages of the disease and affects other motor activities. This study investigated changes in temporospatial gait variables after cerebrospinal fluid (CSF) removal using a spinal tap test in individuals with idiopathic normal pressure hydrocephalus (iNPH), and explored if the tap test responders and non-responders could be clinically identified from temporospatial gait variables. Sixty-two individuals with iNPH were recruited from an outpatient clinic, eleven were excluded, leaving a total of 51 who were included in the analysis. Temporospatial gait variables at self-selected speed were recorded at pre- and 24-h post-tap tests which were compared using Paired t-tests, Cohen's d effect size, and percentage change. A previously defined minimal clinical important change (MCIC) for gait speed was used to determine the changes and to classify tap test responders and non-responders. A mixed model ANOVA was used to determine the within-group, between-group, and interaction effects. Comparisons of the data between pre- and post-tap tests showed significant improvements with small to medium effect sizes for left step length, right step time, stride length and time, cadence, and gait speed. Gait speed showed the largest percentage change among temporospatial gait variables. Within-group and interaction effects were found in some variables but no between-group effect was found. Tap test responders showed significant improvements in right step length and time, stride length and time, cadence, and gait speed while non-responders did not. Some individuals with iNPH showed clinically important improvements in temporospatial gait variables after the tap test, particularly in step/stride length and time, cadence, who could be classified by gait speed. However, gait-related balance variables did not change. Therefore, additional treatments should focus on improving such variables.

[Use of modern classification systems for complex diagnostics of Alzheimer's disease]. / Primenenie sovremennykh klassifikatsionnykh sistem dlya kompleksnoi diagnostiki bolezni Al'tsgeimera.

OBJECTIVE: To compare the content of ß-amyloid (Aß) peptides Aß40, Aß42, total and threonine phosphorylated 181 tau-protein in cerebrospinal fluid (CSF) of patients with the clinical diagnosis of Alzheimer's disease (AD). MATERIAL AND METHODS: The study was performed on 64 patients with a diagnosis of dementia and MMSE scores of 24 or lower. All patients underwent lumbar puncture. Aß40, Aß42, Aß42/40 ratio, total tau, phosphorylated tau at threonine 181 were determined in the CSF using a multiplex assay according to the manufacturer's protocol, the concentration was determined in pkg/ml. RESULTS: The preliminary diagnosis of AD was made in 3 patients (5%). As a result of the study of protein content in the CSF, signs of AD were detected in 48 (75%) people. The findings suggest that the diagnosis of AD is made 10-14 times less frequently than it should be according to the World Health Organization data. The discrepancy between clinical diagnosis and laboratory findings is confirmed by our study. CONCLUSION: Differences in the therapy of dementias and the development of new drugs targeting specific links in the pathogenesis of different types of dementias require accurate and complete diagnosis of dementias, especially AD, as the most common type of dementia.

Physician's conceptions of the decision-making process when managing febrile infants ≤ 60 days old: a phenomenographic qualitative study.

BACKGROUND: The management of febrile infants aged ≤ 60 days and adherence to guidelines vary greatly. Our objective was to describe the process of decision-making when managing febrile infants aged ≤ 60 days and to describe the factors that influenced this decision. METHODS: We conducted 6 focus group discussions with 19 clinically active physicians in the pediatric emergency departments of 2 university hospitals in Skåne region, Sweden. We followed an inductive qualitative design, using a phenomenological approach. A second-order perspective was used, focusing on how physicians perceived the phenomenon (managing fever in infants) rather than the phenomenon itself. The transcribed interviews were analyzed using a 7-step approach. RESULTS: Performing a lumbar puncture (LP) was conceived as a complex, emotionally and mentally laden procedure and dominated the group discussions. Three central categories emerged as factors that influenced the decision-making process on whether to perform an LP: 1) a possible focus of infection that could explain the origin of the fever, 2) questioning whether the temperature at home reported by the parents was a fever, especially if it was ≤ 38.2°C, and 3) the infant's general condition and questioning the need for LP in case of well-appearing infants. Around these 3 central categories evolved 6 secondary categories that influenced the decision-making process of whether to perform an LP or not: 1) the physicians' desire to be able to trust their judgement, 2) fearing the risk of failure, 3) avoiding burdensome work, 4) taking others into account, 5) balancing guidelines and resources, and 6) seeing a need to practice and learn to perform LP. CONCLUSIONS: The difficulty and emotional load of performing an LP were important factors that influenced the decision-making process regarding whether to perform an LP. Physicians highlighted the importance of being able to rely on their clinical judgment and make independent decisions. Guidelines may consider allowing a degree of flexibility and independent thinking to take into account patients' characteristics and needs.

Case 325.

HISTORY: A 76-year-old woman with a history of rheumatoid arthritis, Sjögren syndrome, and hypertension presented with a headache, fever, and dysphagia. The patient was taking prednisone and leflunomide to treat rheumatoid arthritis. Her headache was primarily left sided and occasionally radiated to the occipital region. The patient had a high-grade fever spike, with a temperature of 104°F (40°C). Results of a prior lumbar puncture and temporal artery biopsy from an outside hospital were negative. Findings of a neurologic examination were unremarkable. Oropharyngeal examination for dysphagia revealed minimal pharyngeal motility, with pooling of food in the pharynx, which was thought to be due to cranial nerve dysfunction. Laboratory analysis revealed that, except for anemia, complete blood count parameters were within normal limits. C-reactive protein level (49.7 mg/L; reference range, 0.0-8.0 mg/L), erythrocyte sedimentation rate (>140 mm/h with Westergren method; reference range, 0-27 mm/h), and brain-type natriuretic peptide level (145 pg/mL; reference range, 0-100 pg/mL) were elevated. Blood and urine cultures were negative. A lumbar puncture was performed, which revealed cloudy cerebrospinal fluid (CSF), with an elevated CSF protein level (78 mg/dL; reference range, 7.0-35.0 mg/dL) and a low CSF glucose level (37 mg/dL [2.05 mmol/L]; reference range, 45-70 mg/dL [2.50-3.89 mmol/L]); otherwise, CSF encephalopathy, an autoimmune panel, and cultures were negative. MRI and CT scans of the brain with paranasal sinus were performed (Figs 1-3). Nasal endoscopy-guided drainage of the preclival fluid collection was performed, and biopsy of nasopharyngeal tissue was performed. Fluid culture revealed the growth of Candida albicans, as well as Pseudomonas and Enterobacter aerogenes. The patient received fluconazole, ceftriaxone, vancomycin, and metronidazole. Follow-up MRI was performed after 2 weeks (Fig 4).

Quantitative anatomical analysis of lumbar interspaces based on 3D CT imaging: optimized segment selection for lumbar puncture in different age groups.

BACKGROUND: Optimal lumbar puncture segment selection remains controversial. This study aims to analyze anatomical differences among L3-4, L4-5, and L5-S1 segments across age groups and provide quantitative evidence for optimized selection. METHODS: 80 cases of CT images were collected with patients aged 10-80 years old. Threedimensional models containing L3-S1 vertebrae, dural sac, and nerve roots were reconstructed. Computer simulation determined the optimal puncture angles for the L3-4, L4-5, and L5-S1 segments. The effective dural sac area (ALDS), traversing nerve root area (ATNR), and area of the lumbar inter-laminar space (ALILS) were measured. Puncture efficacy ratio (ALDS/ALILS) and nerve injury risk ratio (ATNR/ALILS) were calculated. Cases were divided into four groups: A (10-20 years), B (21-40 years), C (41-60 years), and D (61-80 years). Statistical analysis was performed using SPSS. RESULTS: 1) ALDS was similar among segments; 2) ATNR was greatest at L5-S1; 3) ALILS was greatest at L5-S1; 4) Puncture efficacy ratio was highest at L3-4 and lowest at L5-S1; 5) Nerve injury risk was highest at L5-S1. In group D, L5-S1 ALDS was larger than L3-4 and L4-5. ALDS decreased after age 40. Age variations were minimal across parameters. CONCLUSION: The comprehensive analysis demonstrated L3-4 as the optimal first-choice segment for ages 10-60 years, conferring maximal efficacy and safety. L5-S1 can serve as an alternative option for ages 61-80 years when upper interspaces narrow. This study provides quantitative imaging evidence supporting age-specific, optimized lumbar puncture segment selection.

Clinical parameter-based prediction model for neurosyphilis risk stratification.

Accurately predicting neurosyphilis prior to a lumbar puncture (LP) is critical for the prompt management of neurosyphilis. However, a valid and reliable model for this purpose is still lacking. This study aimed to develop a nomogram for the accurate identification of neurosyphilis in patients with syphilis. The training cohort included 9,504 syphilis patients who underwent initial neurosyphilis evaluation between 2009 and 2020, while the validation cohort comprised 526 patients whose data were prospectively collected from January 2021 to September 2021. Neurosyphilis was observed in 35.8% (3,400/9,504) of the training cohort and 37.6% (198/526) of the validation cohort. The nomogram incorporated factors such as age, male gender, neurological and psychiatric symptoms, serum RPR, a mucous plaque of the larynx and nose, a history of other STD infections, and co-diabetes. The model exhibited good performance with concordance indexes of 0.84 (95% CI, 0.83-0.85) and 0.82 (95% CI, 0.78-0.86) in the training and validation cohorts, respectively, along with well-fitted calibration curves. This study developed a precise nomogram to predict neurosyphilis risk in syphilis patients, with potential implications for early detection prior to an LP.

Transforaminal endoscopic lumbar discectomy using a 45° puncture angle and foraminotomy versus traditional THESYS for L5/S1 lumbar disc herniation: a prospective randomized controlled trial.

PURPOSE: Prospective comparison of the efficacy and safety of transforaminal endoscopic lumbar discectomy (TELD) with a 45° puncture angle versus traditional Thomas Hoogland endoscopy spine systems (THESYS) for the surgical treatment of L5/S1 lumbar disc herniation (LDH). METHODS: Consecutive patients with L5/S1 LDH who underwent TELD were randomized (1:1) assigned to the 45° TELD group and the THESYS group. Clinical outcomes were assessed at pre-operation, 1-day and 3/6-months post-operation till final follow-up. Surgical-related parameters, visual analogue scale (VAS) score, oswestry disability index (ODI), and modified MacNab criteria, and surgical complications were recorded and analysed. RESULTS: All patients were followed up for at least 24 months. Compared to the THESYS group, the 45° TELD group had a shorter operative time (P < 0.001) and intraoperative radiation time (P < 0.001) and a smaller VAS score for back pain (P < 0.001) and leg pain intraoperatively (P < 0.001). The VAS and ODI in the 45° TELD group were significantly better than those in the THESYS group within 3 months postoperatively. However, from 3 months on, both groups showed comparable VAS and ODI. There was no significant difference between the two groups of modified MacNab criteria. There were two cases of residual disc and two cases of recurrence that required reoperation in the THESYS group. CONCLUSION: For L5/S1 LDH, the 45° TELD technique was superior to traditional THESYS in terms of surgery-related parameters and faster improvement of VAS and ODI, with a lower complication rate.

CT-guided percutaneous cyanoacrylate injection targeting the spinal cerebrospinal fluid leak: a potential therapeutic option for spontaneous intracranial hypotension.

BACKGROUND: We report the first case series of spontaneous intracranial hypotension (SIH) patients who underwent CT-guided percutaneous cyanoacrylate injection targeting the cerebrospinal fluid (CSF) leak. METHODS: A retrospective analysis was performed for all consecutive cases of SIH patients with CSF leak confirmed on CT myelography, treated by CT-guided percutaneous cyanoacrylate injection at our institution from 2016 to 2022. On pretreatment brain and spine MRIs, we analyzed signs of SIH according to the Bern score, and dichotomized cases into positive/negative for spinal longitudinal extradural CSF collection (SLEC-P or SLEC-N). The leaks detected on CT myelography were classified into three types according to Schievink et al. We collected the Headache Impact Test 6 (HIT-6) scores throughout a 6-month follow-up, with a brain CT scan at each visit. RESULTS: 11 patients were included (mean age 48.4 years, six men). Five SLEC-P type 1, three SLEC-P type 2, and three SLEC-N type 3 leaks were identified. All patients had significant signs of SIH on pretreatment brain MRI (mean Bern score 7.8±1.1). Six patients underwent a foraminal puncture, and five patients had a cervical epidural approach. Two patients experienced mild and transient locoregional pain after cervical epidural injection. Mean HIT-6 score at baseline was 66.8±3.2 and at the 6-month follow-up was 38±3.6 (P<0.001). All patients achieved improvement in their symptoms, with 82% of them (9/11) having complete resolution of headaches and SIH findings on CT scans at 6 months. No clinical worsening or recurrence was observed. CONCLUSIONS: CT-guided percutaneous cyanoacrylate injection may be a potential therapeutic option for the different types of CSF leak causing SIH.

Ultrasonography versus palpation for spinal anesthesia in obese parturients undergoing cesarean delivery: a randomized controlled trial.

INTRODUCTION: Ultrasonography may facilitate neuraxial blocks in obstetrics. This randomized controlled trial aimed to compare preprocedural ultrasonography with landmark palpation for spinal anesthesia in obese parturients undergoing cesarean delivery. METHODS: 280 American Society of Anesthesiologists (ASA) physical status II-III parturients with body mass index ≥35 kg/m2, full-term singleton pregnancy, undergoing elective cesarean delivery under spinal anesthesia, were randomly assigned to two equal groups (ultrasonography and palpation); preprocedural systematic ultrasound approach and conventional landmark palpation were performed, respectively. Patients and outcome assessors were blinded to the study group. All ultrasound and spinal anesthetic procedures were performed by a single experienced anesthesiologist. The primary outcome was the number of needle passes required to obtain free cerebrospinal fluid (CSF) flow. Secondary outcomes were the number of skin punctures required to obtain free CSF flow, success rate at the first needle pass, success rate at the first skin puncture, duration of the spinal procedure, patient satisfaction and incidence of vascular puncture, paresthesia, failure to obtain CSF flow and failed spinal block. RESULTS: There were no significant differences in primary or secondary outcomes between the two groups. The median (IQR) of the number of needle passes required to obtain free CSF flow was 3 (1-7) in ultrasonography group and 3 (1-7) in palpation group; p=0.62. CONCLUSIONS: Preprocedural ultrasonography did not decrease the number of needle passes required to obtain free CSF flow or improve other outcomes compared with landmark palpation during spinal anesthesia performed by a single experienced anesthesiologist in obese parturients undergoing cesarean delivery. TRIAL REGISTRATION NUMBER: NCT03792191; : https://clinicaltrials.gov/ct2/show/NCT03792191.

Sphenopalatine ganglion blocks for post-dural puncture headache: A case report in a 3-year-old child.

Post-dural puncture headache is a distressing complication that may occur after lumbar puncture or unintentional dural puncture. Risk factors in the pediatric population have not been well elicited, and the true incidence is unknown. Conservative management includes conservative physical measures and medical therapies. Epidural blood patch remains the gold standard for managing severe refractory headache, but greater occipital nerve blocks and sphenopalatine ganglion blocks have been used with success. Sphenopalatine ganglion blocks are easy to perform, minimally invasive and, in the postoperative setting where epidural analgesia is utilized, provide an alternative that should be considered.