The effects of needle deformation during lumbar puncture

Changes in needle maneuver space and optimal insertion site for midline neuraxial puncture with progressive age: an analysis in computed tomography scans

INTRODUCTION

We systematically describe the morphology and accessibility of interspinous spaces across age groups of patients. Our primary goal was to objectively estimate if the maneuver space for a virtual spinal needle changes with age. Our secondary goal was to estimate if the optimal site and angle for midline neuraxial puncture change with age.

METHODS

Measurements were performed in mid-sagittal CT images. The CT images were retrospectively collected from the database of the Department of Radiology of our hospital. Three age groups were studied: 21-30 years (n=36, abbreviated Y(oung)), 51-60 years (n=43, abbreviated M(iddle-aged)) and older than 80 years (n=46, abbreviated Old).A needle trajectory is defined by the chosen puncture point and by the angle at which the needle is directed to its target. We define a Spinal Accessibility Index (SAI) by numerically integrating for an interspace all possible combinations of puncture points and angles that lead to a successful virtual puncture. Successful in this context means that the needle tip reaches the spinal or epidural space without bone contact. Reproducible calculation of the SAI was performed with the help of custom-made software. The larger the value of the SAI, the more possible successful needle trajectories exist that the practitioner may choose from.The optimal puncture point and optimal angle in an age group at a certain level of the spine are defined by the combination of these two, which generates the highest success rate of the entire sample of this age group.

RESULTS

At all levels of the spine, the median SAI differed significantly between age groups (independent-samples Kruskal-Wallis test, p<0.001-0.047). The SAI consistently decreased with increasing age. Post-hoc analyses using pairwise comparisons showed a significantly higher SAI in group Y versus Old at all levels (p<0.001-0.006) except at level thoracic (Th)1-Th2 (p=0.138). The SAI was significantly higher in group M versus Old at all levels (p<0.001-0.028) except at level Th1-Th2 (p=0.061), Th4-Th5 (p=0.083), Th9-Th10 (p=1.00) and Th10-Th11 (p=1.00).

CONCLUSIONS

Needle maneuver space in midline neuraxial puncture significantly decreases with progressive age at all levels of the spine. Optimal puncture points and angles are similar between age groups.

Optimized Method of Unilateral Spinal Anesthesia: A Double-blind, Randomized Clinical Study

Background

Unilateral spinal anesthesia is often accompanied by technical difficulties in implementation, multiple puncture attempts, unsuccessful punctures, and, as a result, insufficient anesthesia, along with various complications associated with a dural puncture.

Objectives

This work compares the efficacy and safety of conventional Unilateral Spinal Anesthesia (USpA) and unilateral spinal anesthesia with electrical nerve stimulation (USpA+ENS).

Methods

A total of 134 patients with an upcoming vascular surgery on one lower extremity were randomly assigned to two groups. All the patients were positioned with the operated limb below and used 7.5 mg of Bupivacaine-Spinal®. In the UsPA group, anesthesia was performed according to the standard technique. In the USpA+ENS group, electrical nerve stimulation was additionally used. Primary outcomes were the presence or absence of post-dural puncture headache (PDPH), number of puncture attempts, lateralization, and anesthesia adequacy. Secondary outcomes were intraoperative pain scores, the presence or absence of nausea and vomiting, and the need for hemodynamics correction.

Results

The frequency of puncture complications was sufficiently lower in the USpA+ENS group than in the UsPA group. The local anesthetic solution distribution, pain score indicators, and secondary outcomes were comparable in both groups with a slight difference.

Conclusions

We showed that USpA+ENS reduces the incidence of puncture complications and improves the quality of anesthesia and adherence of both patients and anesthesiologists to the unilateral spinal anesthesia technique.

Assessment of High Risk for Alzheimer's Disease Using Plasma Biomarkers in Subjects with Normal Cognition in Taiwan: A Preliminary Study

Background

In Alzheimer's disease (AD), cognitive impairment begins 10-15 years later than neurodegeneration in the brain. Plasma biomarkers are promising candidates for assessing neurodegeneration in people with normal cognition. It has been reported that subjects with the concentration of plasma amyloid-β 1-42×total tau protein higher than 455 pg²/ml² are assessed as having a high risk of amnesic mild impairment or AD, denoted as high risk of AD (HRAD).

Objective

The prevalence of high-risk for dementia in cognitively normal controls is explored by assaying plasma biomarkers.

Methods

422 subjects with normal cognition were enrolled around Taiwan. Plasma Aβ_1-40, Aβ_1-42, and T-Tau levels were assayed using immunomagnetic reduction to assess the risk of dementia.

Results

The results showed that 4.6% of young adults (age: 20-44 years), 8.5% of middle-aged adults (age: 45-64 years), and 7.3% of elderly adults (age: 65-90 years) had HRAD. The percentage of individuals with HRAD dramatically increased in middle-aged and elderly adults compared to young adults.

Conclusion

The percentage of HRAD in cognitively normal subjects are approximately 10%, which reveals that the potentially public-health problem of AD in normal population. Although the subject having abnormal levels of Aβ or tau is not definitely going on to develop cognitive declines or AD, the risk of suffering cognitive impairment in future is relatively high. Suitable managements are suggested for these high-risk cognitively normal population. Worth noting, attention should be paid to preventing cognitive impairment due to AD, not only in elderly adults but also middle-aged adults.

Preventing Post-Lumbar Puncture Headache

Post-lumbar puncture headache is the main adverse event from lumbar puncture and occurs in 3.5% to 33% of patients, causing functional and socio-professional disability. We searched the post-lumbar puncture headache literature and, based on this review and personal expertise, identified and addressed 19 frequently asked questions regarding post-lumbar puncture headache risk factors and prevention. Among the nonmodifiable factors, older age is associated with a lower incidence of post-lumbar puncture headache, while female sex, lower body mass index, and history of headache might be associated with increased risk. The use of atraumatic, noncutting needles is the most effective intervention for post-lumbar puncture headache prevention. These needles are not more difficult to use than cutting needles. Other commonly recommended measures (eg, fluid supplementation, caffeine) appear unhelpful, and some (eg, bed rest) may worsen post-lumbar puncture headache.