Real-time Ultrasound-guided Spinal Anesthesia Using a New Paramedian Transverse Approach

Landmark-guided versus Real-time Ultrasound-guided Combined Spinal-epidural Anesthesia Techniques: Paramedian Sagittal Oblique and Transverse Interlaminar Approach

Background

There are different types of real-time ultrasound (US)-guided combined spinal epidural (CSE) anesthesia techniques. We aimed to investigate the effect of real-time US-guided paramedian sagittal oblique (PSO), transverse interlaminar (TI) approach method, and landmark-guided (LG) CSE anesthesia.

Methods

Ninety patients who underwent CSE block were included in the study. Patients were randomized into LG (n = 30), PSO (n = 30), and TI (n = 30) groups. The primary outcome was number of needle manipulations. The secondary outcomes are the number of attempts, needle visibility, procedure time, procedure success rate, catheter placement difficulty, posterior complex distance, and complications.

Results

The number of needle manipulations was statistically significantly lower in the LG technique group (P < 0.000). When the number of attempts, the difficulty of catheter placement, and the procedure's success rate were compared between the three groups, we did not find a statistically significant difference (P > 0.05). In addition, when the procedure times were compared, the time measured for the LG group was statistically significantly lower than in the PSO and TI groups (P < 0.000).

Conclusion

In the results of this study, the real-time US-guided CSE anesthesia application had a similar success and complication level with LG technique. The LG method had a shorter processing time and fewer needle manipulations.

Administration of combined spinal epidural anesthesia with ultrasound-assisted positioning in obese patients undergoing open hysterectomy: A randomized controlled trial

BACKGROUND

Administration of combined spinal epidural anesthesia (CSEA) with traditional landmark-guided positioning can be challenging in patients with high body mass index (BMI). The popularization of ultrasound technology may effectively solve these problems. However, reports on the administration of CSEA ultrasound-assisted positioning in obese populations are relatively limited and have made inconsistent conclusions. We aimed to investigate the ability of ultrasound-assisted positioning to improve the success rate of CSEA in obese patients.

METHODS

Overall, 118 adult women with a BMI ≥ 30 kg/m2 who scheduled to undergo open hysterectomy and received CSEA were recruited. Finally, 108 patients were enrolled and randomly assigned to 2 groups: the ultrasound-assisted positioning group (group A) and traditional landmark-guided positioning group (group B). Ultrasound-assisted or landmark-guided positioning was employed to locate the puncture interspace before anesthesia. The primary outcomes were the success rate of first attempt and number of attempts. The secondary outcomes were the patient positioning accuracy, positioning time, CSEA operation time, patient-satisfaction scores, anesthesia characteristics, and complications of CSEA.

RESULTS

The success rate of patient first puncture attempt in group A was significantly higher than that in group B (78.4% vs 52.9%, P = .007). The total number of punctures was lower in group A than that in groups B (average rank 44.54 vs 58.46, P = .005). Using ultrasound positioning as the gold standard, the accuracy of landmark-guided location was only 67%. Positioning time in croup A was longer in group A than that in group B (P = .004), while CSEA operation time spent in Group A was less than that in Group B (P < .001). Patient satisfaction score in group A was significantly higher than that in group B (P = .002). The successful puncture interspace in group A were more likely at L3-4 than that in group B (P = .02).

CONCLUSION

The success rate of first puncture attempt and positioning accuracy in CSEA with ultrasound-assisted is significantly higher than those based on landmark-guided location in obese patients.

Comparison of ultrasound-guided and traditional localisation in intraspinal anesthesia: a systematic review and network meta-analysis

OBJECTIVES

The optimal puncture technique for neuraxial anaesthesia in different populations is unclear. We sought to obtain data from randomised controlled trials comparing the impact of ultrasound-guided technology and traditional positioning technology on the success rate of neuraxial anaesthesia.

DESIGN

Systematic review and network meta-analysis using study populations, interventions, intervention comparisons, outcome measures and study types.

DATA SOURCES

PubMed, Embase, Cochrane Library and Web of science were searched until 31 September 2022.

ELIGIBILITY CRITERIA

We included randomised controlled trials comparing three types of neuraxial anaesthesia: ultrasound-assisted, ultrasound real-time guidance and conventional positioning to describe which neuraxial anaesthesia modality is best for patients and to recommend the appropriate one for different populations.

DATA EXTRACTION AND SYNTHESIS

Five independent reviewers retrieved, screened and edited included studies using standardised methods. Assess risk of bias using the Cochrane Collaboration and Evidence Project tools. Network meta-analysis was performed using STATA V.15 statistical software.

RESULTS

Twenty-two studies containing three different interventions were included. The SUCRA values of first-pass success rates for the three neuraxial anaesthesia methods were real-time guidance (82.8%), ultrasound-assisted (67.1%) and traditional positioning (0.1%). Both ultrasound techniques improved first-pass success rates compared with traditional localization, but there was no significant difference between the two. Subgroup analysis showed that the use of real-time ultrasound guidance for neuraxial anaesthesia in pregnant and patients with obesity improved first-pass success rates. Ultrasound-assisted technology can improve first-attempt success rates in older patients with abnormal lumbar spine anatomy.

CONCLUSION

Compared with conventional positioning, ultrasound guidance technology can improve the first-pass success rate of neuraxial anaesthesia, but there is no significant difference between ultrasound-assisted and real-time guidance technology. The results of subgroup analysis tell us that the most suitable neuraxial anaesthesia method is different for different groups of people.

PROSPERO REGISTRATION NUMBER

PROSPERO number: CRD42022376041.

Spinal sonography and central neuraxial blocks

Central neuraxial blocks (CNBs), which include spinal, epidural, and combined spinal epidural injections, are indispensable techniques in the anesthesiologist's armamentarium. Indeed, in scenarios such as when dealing with the obstetric population, patients with obesity, or patients having respiratory compromise (e.g., lung disease or scoliosis), CNBs are the mainstay for anesthesia and/or analgesia. Traditionally, CNBs are performed using anatomical landmarks, which are simple, easy to master, and exceptionally successful in most cases. Nevertheless, there are notable limitations with this approach, especially in scenarios where CNBs are considered mandatory and vital. Any limitation of an anatomic landmark-based approach is an opportunity for an ultrasound-guided (USG) technique. This has become particularly true for CNBs, where recent advances in ultrasound technology and research data have addressed many of the shortcomings of the traditional anatomic landmark-based approaches. This article reviews the ultrasound imaging of the lumbosacral spine and its application for CNBs.

Comparing the minimum local anesthetic dose of ropivacaine in real-time ultrasound-guided spinal anesthesia and traditional landmark-guided spinal anesthesia: a randomized controlled trial of knee surgery patients

Background

Through previous studies and clinical practice, we have found that real-time ultrasound-guided (UG) spinal anesthesia (SA) and traditional landmark-guided (LG) SA each require a different minimum local anesthetic dose (MLAD) of ropivacaine. For this study, we used Dixon’s up-and-down sequential method to analyze and compare the MLAD of different ropivacaine concentrations required for the UG and LG SA methods.

Methods

A total of 120 patients undergoing knee surgery were consecutively recruited and randomly divided into four groups (30 patients per group). These groups were categorized as follows: Group I: high ropivacaine ultrasound-guided (HRUG), Group II: low ropivacaine ultrasound-guided (LRUG), Group III: high ropivacaine landmark-guided (HRLG), and Group IV: low ropivacaine landmark-guided (LRLG). SA was established by a bolus administration of up-and-down doses of 0.75% or 0.5% plain ropivacaine. Initial doses of 16, 18, 12, and 14 mg were administered to groups I–IV, and after that, increased or decreased by 1.5 mg according to dose effectiveness. Upon identifying the intervertebral puncture level, a lumbar X-ray was performed with metal markers, and actual radiographic findings were identified and compared to the initial markings.

Results

For UG groups, the MLAD in the LRUG group was significantly higher than in the HRUG group [20.192 mg (95% CI, 19.256–21.174) versus 17.176 mg (95% CI, 16.276–18.124), respectively; P<0.001]. For LG groups, the MLAD in the LRLG group was significantly higher than in the HLRG group [14.478 mg (95% CI, 13.364–15.500) versus 13.201 mg (95% CI, 11.959–14.571), respectively; P=0.047]. When comparing both high ropivacaine groups (HRGs: I/III) to the low ropivacaine groups (LRGs: II/IV), we found that both UG subgroups (I/II) had a significantly higher MLAD than LG subgroups (III/IV) (P<0.001). US identified L4–5 in up to 90% of cases. Comparatively, palpation was successful in only 33.3% of patients. The rates of cephalad localization by US and palpation were 6.67% vs. 66.67%, respectively (P=0.002).

Conclusions

We found a higher MLAD of ropivacaine was required for UG SA at the L4–5 level due to the method providing a more accurate (less cephalad) localization than traditional LG SA.

Trial Registration

Chinese Clinical Trial Registry ChiCTR2000033158.

Real-Time Ultrasound-Guided Versus Ultrasound-Assisted Spinal Anesthesia in Elderly Patients With Hip Fractures: A Randomized Controlled Trial

BACKGROUND

Traditional landmark-guided spinal anesthesia can be challenging in elderly patients with hip fractures. Ultrasound assistance (USAS) and real-time ultrasound guidance (USRTG) techniques can facilitate lumbar neuraxial blocks. However, it remains undetermined which method is optimal for use in elderly patients. This study aimed to evaluate which technique was associated with a higher success rate of spinal anesthesia in elderly patients with hip fractures: USAS or USRTG technique.

METHODS

A total of 114 elderly patients (≥70 years of age) with hip fractures were randomly assigned to receive spinal anesthesia using either the USAS or USRTG technique. The primary outcome was the first-attempt success rate, analyzed using the χ2 test. Secondary outcomes included first-pass success rate, the number of needle attempts and passes, locating time, procedure time, total time, adverse reactions and complications, patient satisfaction, and procedural difficulty score.

RESULTS

The first-attempt success rate (80.7% vs 52.6%; 95% confidence interval [CI], for the difference, 11.6-44.6) and first-pass success rate (63.2% vs 31.6%; 95% CI for the difference, 14.2-49) were both significantly higher in the USAS compared with the USRTG group (both P = .001). The number of attempts (1 [1-1] vs 1 [1-3]; P = .001) and median passes (1 vs 3; P < .001) were both significantly lower in the USAS group than in the USRTG group. The USRTG group had a shorter locating time (175 seconds [129-234 seconds] vs 315 seconds [250-390 seconds]; P < .001) but a longer procedure time (488 seconds [260-972 seconds] vs 200 seconds [127-328 seconds]; P < .001) and total time (694 seconds [421-1133 seconds] vs 540 seconds [432-641 seconds]; P = .036). There were no significant differences between the 2 groups with regard to the adverse reactions and complications. More patients in the USAS group had a high satisfaction score of 3 to 5 (P = .008). Overall, anesthesiologists rated the USRTG group procedure as "more difficult" (P = .008).

CONCLUSIONS

In elderly patients with hip fractures, spinal anesthesia with the USRTG technique is not superior to the USAS technique since it has a lower success rate, longer procedure time, lower satisfaction score, and is more difficult to perform. So USAS technique may be more suitable for elderly patients.

Dry spinal tap during real-time ultrasound-guided paramedian spinal injection with patient in the lateral decubitus position: A single-centre retrospective study

BACKGROUND

Real-time ultrasound-guided (USG) spinal injection is generally performed via the paramedian sagittal oblique (PMSO) ultrasound window.

OBJECTIVE

The aim of this retrospective study was to draw attention to the occurrence of 'dry tap' during real-time USG spinal injection.

DESIGN

Single-centre retrospective study.

SETTING

University teaching hospital, Hong Kong, China.

PATIENTS

Data from 113 patients (aged 69.2 ± 18.0 years and BMI 22.3 ± 3.6 kg m-2) of American Society of Anesthesiologists physical status 1 to 3 scheduled for surgery under neuraxial blockade between 2007 to 2017 were reviewed.

INTERVENTIONS

Real-time USG spinal injections or combined spinal-epidural (CSE) using the PMSO ultrasound window with the patient in the lateral decubitus position and the spinal needle inserted from the nondependent side were studied.

MAIN OUTCOME MEASURES

'Dry tap' was defined as a failure of cerebrospinal fluid (CSF) to efflux from the hub of the needle, within 3 min, with the spinal needle visualised sonographically within the thecal sac. 'Slow CSF efflux' was defined as efflux of CSF within 1 to 3 min. Irrespective of whether it was a 'dry tap' or 'slow CSF efflux', the planned dose of local anaesthetic was injected through the spinal needle.

RESULTS

The combined incidence of 'dry tap' and 'slow CSF efflux' was 23.8% (27/113) with an individual incidence for each event of 9.7% (11/113) and 14.2% (16/113), respectively. Under the conditions of this study, successful spinal anaesthesia developed in all patients.

CONCLUSION

'Dry tap' occurs in 9.7% of cases during real-time USG spinal injection using the PMSO ultrasound window, with the patient in the lateral decubitus position and the spinal needle inserted from the nondependent side.

TRIAL REGISTRATION

ChiCTR-IOR-1800019011, Chinese Clinical Trials Registry (www.chictr.org.cn).

Ultrasonography for lumbar neuraxial block

Ultrasonography can be useful to perform a lumbar neuraxial block. It aids in understanding the anatomy of the lumbar spine before the procedure. Pre-procedural ultrasound imaging provides information about the accurate intervertebral level for puncture, optimal needle insertion point, and depth of needle advancement for a successful neuraxial block. The key ultrasonographic views for lumbar neuraxial block include the transverse midline interlaminar and parasagittal oblique views. Ultrasonography can facilitate lumbar neuraxial block in difficult cases, such as the elderly, obese patients, and patients with anatomical abnormality of the lumbar spine. This review elucidates the basics of spinal ultrasonography for lumbar neuraxial block and the current evidence regarding ultrasound-guided neuraxial block in adults.

Ultrasound-Guided Neuraxial Anesthesia

PURPOSE OF REVIEW

There has been a recent surge of interest in clinical applications of ultrasound, which has revolutionized acute pain management. This review is to summarize the current status of ultrasound utilization in neuraxial anesthesia, the most common type of regional anesthesia.

RECENT FINDINGS

Ultrasound-assisted and ultrasound-guided neuraxial anesthesia has improved clinical accuracy and patient safety through landmark identification including proper vertebral level and midline, as well as via measurements on neuraxial space. Direct needle or catheter visualization during the entire procedure has not yet been achieved consistently. The recent introduction of ultrasound into neural anesthesia has clinical performance benefits and patient safety implications, with documented improvement on overall efficacy with higher first attempt success rate as well as less needle pass. More controlled studies are needed for the overall impact of ultrasonography in neuraxial anesthesia in obstetric and non-obstetric patients.

Minimum local anesthetic dose of ropivacaine in real-time ultrasound-guided intraspinal anesthesia for lower extremity surgery: a randomized controlled trial

Background

Despite the many advantages real-time ultrasound-guided lumbar anesthesia has over traditional lumbar anesthesia, it seemingly involves a much higher dose of ropivacaine. This study aimed to determine the minimum local anesthetic dose (MLAD) and the 95% confidence interval of ropivacaine at different concentrations in real-time ultrasound-guided lumbar anesthesia for lower extremity surgery.

Methods

A total of 60 patients who were consecutively scheduled for selective lower extremity surgery were enrolled. The patients were randomly divided into two groups, which each received different concentrations of ropivacaine at different initial dosages when Dixon's up-and-down sequential method was applied. The high ropivacaine group and the low ropivacaine group received 0.75% and 0.5% ropivacaine, respectively. The patients' baseline characteristics, the MLAD, and the 95% confidence interval were assessed. The highest level of sensory block, time to reach the T10 sensory block, duration for sensory blocks higher than T10, highest plane for sensory block, and onset time and duration for motor block were recorded. Comparisons were also made between the patients' vital signs and adverse reactions.

Results

The minimum local anaesthetic dose (MLAD) and 95% confidence interval in the high ropivacaine group and the low ropivacaine group were 17.176 (16.276 to 18.124) and 20.192 (19.256 to 21.174) mg, respectively. Moreover, motor block maintenance was greatly reduced in the 0.5% ropivacaine compared to the 0.75% ropivacaine group (P=0.0309).

Conclusions

In real-time ultrasound-guided intraspinal anesthesia for lower extremity surgery, both 0.75% and 0.5% ropivacaine provide satisfactory anesthesia. Our results suggest that shortened motor block duration can hold benefits for patients including earlier mobilization and a quicker rehabilitation process.

Chinese Association of Anesthesiologists Expert Consensus on the Use of Perioperative Ultrasound in Coronavirus Disease 2019 Patients

The COVID-19 pandemic is spreading globally. COVID-19 has an effect on the systemic state, cardiopulmonary function and primary disease of patients undergoing surgery. COVID-19's high contagiousness makes anesthesia and intraoperative management more difficult. This expert consensus aims to comprehensively introduce the application of perioperative ultrasound in COVID-19 patients, including pulmonary ultrasound and anesthesia management, ultrasound and airway management, ultrasound-guided regional anesthesia and echocardiography for COVID-19 patients.

Influence of age, laterality, patient position, and spinal level on the interlamina space for spinal puncture

BACKGROUND AND OBJECTIVES

The lumbar interlamina space height is an important determinant of successful spinal puncture. We aimed to evaluate the influence of age, laterality, patient position, and spinal level on the height of the interlamina window using ultrasonography.

METHODS

Ultrasonographic examination was performed in 20 adult patients aged under 40 years (group Y) and 20 patients aged over 60 years (group O). We set three primary outcomes: difference in the interlamina height of the ligamentum flavum-dura mater complex (LFD) according to (1) age, (2) laterality, and (3) position. For secondary outcomes, the degree of ultrasonography visualization (poor, intermediate, or good) and the depths from the skin to LFD and to anterior complex were also measured on right and left paramedian sagittal oblique view in both lateral and sitting positions at L3/4, L4/5, and L5/S1 levels. All variables were analyzed in association with age, laterality, patient position, and spinal level.

RESULTS

The interlamina height of LFD was higher, and the degree of visualization was better in group Y than in group O. It differed depending on laterality in paramedian sagittal oblique view images in the same patients at all spinal levels. The interlamina height of LFD was the largest at L5/S1 level in both groups. Position had little influence on the interlamina height of LFD.

CONCLUSIONS

Scanning both sides and all spinal levels before selecting a puncture site for ultrasound-guided spinal anesthesia is recommended. The L5/S1 spinal level is a good option for spinal puncture in the elderly.

TRIAL REGISTRATION NUMBER

NCT03929874.

Recommendations on the Use of Ultrasound Guidance for Adult Lumbar Puncture: A Position Statement of the Society of Hospital Medicine

When ultrasound equipment is available, along with providers who are appropriately trained to use it, we recommend that ultrasound guidance should be used for site selection of lumbar puncture to reduce the number of needle insertion attempts and needle redirections and increase the overall procedure success rates, especially in patients who are obese or have difficult-to-palpate landmarks. We recommend that ultrasound should be used to more accurately identify the lumbar spine level than physical examination in both obese and nonobese patients. We suggest using ultrasound for selecting and marking a needle insertion site just before performing lumbar puncture in either a lateral decubitus or sitting position. The patient should remain in the same position after marking the needle insertion site. We recommend that a low-frequency transducer, preferably a curvilinear array transducer, should be used to evaluate the lumbar spine and mark a needle insertion site. A high-frequency linear array transducer may be used in nonobese patients. We recommend that ultrasound should be used to map the lumbar spine, starting at the level of the sacrum and sliding the transducer cephalad, sequentially identifying the lumbar spine interspaces. We recommend that ultrasound should be used in a transverse plane to mark the midline of the lumbar spine and in a longitudinal plane to mark the interspinous spaces. The intersection of these two lines marks the needle insertion site. We recommend that ultrasound should be used during a preprocedural evaluation to measure the distance from the skin surface to the ligamentum flavum from a longitudinal paramedian view to estimate the needle insertion depth and ensure that a spinal needle of adequate length is used. We recommend that novices should undergo simulation-based training, where available, before attempting ultrasound-guided lumbar puncture on actual patients. We recommend that training in ultrasound-guided lumbar puncture should be adapted based on prior ultrasound experience, as learning curves will vary. We recommend that novice providers should be supervised when performing ultrasound-guided lumbar puncture before performing the procedure independently on patients.