Spinal Anesthesia Reduces Perioperative Polypharmacy and Opioid Burden in Patients Over 65 Who Undergo Transforaminal Lumbar Interbody Fusion.

BACKGROUND: Polypharmacy and opioid administration are thought to increase the risk of postoperative cognitive dysfunction and delirium in elderly patients. Spinal anesthesia (SA) holds potential to reduce perioperative polypharmacy in spine surgery. As more geriatric patients undergo spine surgery, understanding how SA can reduce polypharmacy and opioid administration is warranted. We aim to compare the perioperative polypharmacy and dose of administered opioids in patients ≥65 years who undergo transforaminal lumbar interbody fusion (TLIF) under SA versus general anesthesia (GA). METHODS: A retrospective analysis of 200 patients receiving a single-surgeon TLIF procedure at a single academic center (2014-2021) was performed. Patients underwent the procedure with SA (n = 120) or GA (n = 80). Demographic, procedural, and medication data were extracted from the medical record. Opioid consumption was quantified as morphine milligram equivalents (MME). Statistical analyses included χ2 or Student's t-test. RESULTS: Patients receiving SA were administered 7.45 medications on average versus 12.7 for GA patients (P < 0.001). Average perioperative opioid consumption was 5.17 MME and 20.2 MME in SA and GA patients, respectively (P < 0.001). The number of patients receiving antiemetics and opioids remained comparable postoperatively, with a mean of 32.2 MME in the GA group versus 27.5 MME in the SA group (P = 0.14). Antiemetics were administered less often as a prophylactic in the SA group (32%) versus 86% in the GA group (P < 0.001). CONCLUSIONS: SA reduces perioperative polypharmacy in patients ≥65 years undergoing TLIF procedures. Further research is necessary to determine if this reduction correlates to a decrease the incidence of postoperative cognitive dysfunction and delirium.

Erector Spinae Plane Block Placement Utilizing Fluoroscopic Guidance Improves Efficiency in Lumbar Surgery.

OBJECTIVE: The erector spinae plane block (ESPB) is a novel regional analgesic technique which improves postoperative outcomes in lumbar surgery patients including length of hospitalization, days to ambulation, and postoperative opioid use. Traditionally, the block is administered by anesthesiologists trained in the ultrasound guidance technique. The use of fluoroscopic guidance may improve the efficiency and accessibility of the ESPB for spine surgeons. We aim to measure the time to administer an ESPB using fluoroscopic guidance and localize the anesthetic using intraoperative three-dimensional (3D) imaging. METHODS: Two neurosurgeons administered an ESPB to patients undergoing lumbar surgery. Time from insertion of the spinal needle to localize the erector spinae plane using C-arm guidance to time of complete injection and removal of the needle from the skin was recorded. One patient underwent O-arm imaging following injection of an Isovue-Exparel solution at the L3 level to visualize spread of the anesthetic. RESULTS: A total of 21 patients were enrolled in this study. The average duration to perform an ESPB under fluoroscopic guidance was 1.2 minutes. The Isovue-Exparel solution was injected at the L3 level and was well distributed along the ESP on intraoperative O-arm imaging. The anesthetic dissected the erector spinae muscle from the transverse process at L2, L3, and L4. CONCLUSIONS: Fluoroscopic guidance allows efficient and appropriate delivery of the anesthetic to the erector spinae plane. Performing an ESPB with fluoroscopic guidance improves efficiency and accessibility of the analgesic technique for spine surgeons, reducing dependence on anesthesiology personnel trained in administering the block.

The Relationship of Spinal Anesthesia Dosing Based on Thecal Sac Area to Anesthetic Failure in Lumbar Surgery.

BACKGROUND AND OBJECTIVES: Greater thecal sac volumes are associated with an increased risk of spinal anesthesia (SA) failure. The thecal sac cross-sectional area accurately predicts thecal sac volume. The thecal sac area may be used to adjust the dose and prevent anesthetic failure. We aim to assess the rate of SA failure in a prospective cohort of lumbar surgery patients who receive an individualized dose of bupivacaine based on preoperative measurement of their thecal sac area. METHODS: A total of 80 patients prospectively received lumbar spine surgery under SA at a single academic center (2022-2023). Before surgery, the cross-sectional area of the thecal sac was measured at the planned level of SA injection using T2-weighted MRI. Patients with an area <175 mm2, equal to or between 175 and 225 mm2, and >225 mm2 received an SA injection of 15, 20, or 25 mg of 0.5% isobaric bupivacaine, respectively. Instances of anesthetic failure and adverse outcomes were noted. Incidence of SA failure was compared with a retrospectively obtained control cohort of 250 patients (2019-2022) who received the standard 15 mg of bupivacaine. RESULTS: No patients in the individualized dose cohort experienced failure of SA compared with 14 patients (5.6%) who experienced failure in the control cohort (P = .0259). The average thecal sac area was 187.49 mm2, and a total 28 patients received 15 mg of bupivacaine, 42 patients received 20 mg of bupivacaine, and 10 patients received 25 mg of bupivacaine. None of the patients experienced any adverse outcomes associated with SA. Patients in the individualized dose cohort and control cohort were comparable and had a similar distribution of lumbar procedures and comorbidities. CONCLUSION: Adjusting the dose of SA according to thecal sac area significantly reduces the rate of SA failure in patients undergoing lumbar spine surgery.

A systematic review and update on diagnosis and treatment of new onset sacroiliac joint dysfunction after lumbar fusion.

BACKGROUND: Sacroiliac joint dysfunction (SIJD) after lumbar/lumbosacral fusion has become increasingly recognized as the utilization of lumbar fusion has grown. Despite the significant morbidity associated with this condition, uncertainty regarding its diagnosis and treatment remains. We aim to update the current knowledge of the etiology, diagnosis, and treatment of post-lumbar surgery SIJD. METHODS: PRISMA guidelines were used to search the PubMed/Medline, Web of Science, Cochrane Reviews, Embase, and OVID databases for literature published in the last 10 years. The ROBIS tool was utilized for risk of bias assessment. Statistical analyses were performed using the R foundation. A Fisher's exact test was performed to determine the risk of SIJD based on operative technique, gender, and symptom onset timeline. Odds ratios were reported with 95% confidence intervals. A p-value [Formula: see text] 0.05 was considered statistically significant. RESULTS: Seventeen publications were included. The incidence of new onset SIJD was 7.0%. The mean age was 56 years, and the follow-up length was 30 months. SIJD was more common with fixed lumbar fusion vs floating fusion (OR = 1.48 [0.92, 2.37], p = 0.083), fusion of [Formula: see text] 3 segments (p < 0.05), and male gender increased incidence of SIJD (OR = 1.93 [1.27, 2.98], p = 0.001). Intra-articular injection decreased the Visual Analogue Scale (VAS) score by 75%, while radiofrequency ablation (RFA) reduced the score by 90%. An open approach resulted in a 13% reduction in VAS score versus 68 and 29% for SIJ fixation using the iFuse and DIANA approaches, respectively. CONCLUSIONS: Lumbar fusion predisposes patients to SIJD, likely through manipulation of the SIJ's biomechanics. Definitive diagnosis of SIJD remains multifaceted and a newer modality such as SPECT/CT may find a future role. When conservative measures are ineffective, RFA and SIJ fixation using the iFuse System yield the greatest improvement VAS and ODI.

Correlation of thecal sac cross sectional area to total volume.

BACKGROUND: Spinal anesthesia (SA) has been increasingly utilized in lumbar surgery due to its various advantages over general anesthesia (GA), however failure of the first dose requiring intraoperative conversion to GA occurs in as many as 3.6% of SA patients. Some studies have reported that a larger thecal sac volume may dilute the anesthetic and play a role in first dose failure. Unfortunately, easy determination of thecal sac volume has not been reported in the literature. Thus, we sought to determine whether cross-sectional area obtained from MRI accurately predicts the volume of the thecal sac. METHODS: We conducted a retrospective review of 80 patients who underwent lumbar surgery with spinal anesthesia. T1 and T2-weighted MRI sequences were used to measure thecal sac area at each level between L1-S1. The volume of the thecal sac was calculated using HorosTM. A statistical model was derived relating the area at each level to the thecal sac volume. Of the 80 patients, 20% were reserved and utilized to test the accuracy of the statistical model. RESULTS: The area of the thecal sac positively correlated with volume at each lumbar level. The area of the thecal sac at the L4-L5 level most accurately represented total thecal sac volume (R2 = 0.588, RMSE = 2.76). CONCLUSION: Cross-sectional area of the L4-L5 spinal level obtained from MRI sequences may be utilized as a proxy for thecal sac volume.

Wirelessly Powered-Electrically Conductive Polymer System for Stem Cell Enhanced Stroke Recovery.

Effective stroke recovery therapeutics remain limited. Stem cell therapies have yielded promising results, but the harsh ischemic environment of the post-stroke brain reduces their therapeutic potential. Previously, we developed a conductive polymer scaffold system that enabled stem cell delivery with simultaneous electrical modulation of the cells and surrounding neural environment. This wired polymer scaffold proved efficacious in optimizing ideal conditions for stem cell mediated motor improvements in a rodent model of stroke. To further enable preclinical studies and enhance translational potential, we identified a method to improve this system by eliminating its dependence upon a tethered power source. We have herein developed a wirelessly powered, electrically conductive polymer system that eases therapeutic application and enables full mobility. As a proof of concept, we demonstrate that the wirelessly powered scaffold is able to stimulate neural stem cells in vitro, as well as in vivo in a rodent model of stroke. This system modulates the stroke microenvironment and increases the production of endogenous stem cells. In summation, this novel, wirelessly powered conductive scaffold can serve as a mobile platform for a wide variety of therapeutics involving electrical stimulation.

The Emerging Significance of Amyloid Deposits in the Ligamentum Flavum of Spinal Stenosis Patients: A Review.

Spinal stenosis is one of the most common neurosurgical diseases and a leading cause of pain and disability. Wild-type transthyretin amyloid (ATTRwt) has been found in the ligamentum flavum (LF) of a significant subset of patients with spinal stenosis who undergo decompression surgery. Histologic and biochemical analyses of LF specimens from spinal stenosis patients, normally discarded as waste, have the potential to help elucidate the underlying pathophysiology of spinal stenosis and possibly allow for medical treatment of stenosis and screening for other systemic diseases. In the present review, we discuss the utility of analyzing LF specimens after spinal stenosis surgery for ATTRwt deposits. Screening for ATTRwt amyloidosis cardiomyopathy through LF specimens has led to the early diagnosis and treatment of cardiac amyloidosis in several patients, with more expected to benefit from this process. Emerging evidence in the literature also point to ATTRwt as a contributor to a previously unrecognized subtype of spinal stenosis in patients who might, in the future, benefit from medical therapy. In the present report, we review the current literature regarding the early detection of ATTRwt cardiomyopathy via LF screening and the possible contribution of ATTRwt deposits in the LF to spinal stenosis development.

Evaluating the potential impact of spinal anesthesia use in lumbar surgery on global healthcare cost and climate change.

Introduction: Despite recent evidence demonstrating its safety and efficacy, spinal anesthesia remains a seldom-utilized anesthetic modality in lumbar surgical procedures. In addition, numerous clinical advantages, such as reduced cost, blood loss, operative time, and inpatient length of stay have been consistently demonstrated with spinal anesthesia over general anesthesia. Research question: In this report we aim to examine the differences between spinal anesthesia and general anesthesia with regard to accessibility and climate impact and determine whether wider adoption of spinal anesthesia would have a meaningful impact on the global population. Materials and Methods: The climate impact of spinal fusions performed under spinal and general anesthesia were obtained from recent studies published in the literature. Cost of spinal fusions was obtained from an unpublished study performed at our institution. Volume of spinal fusions performed in several countries were ascertained from published reports. Data on cost and carbon emissions were extrapolated based on volume of spinal fusions in each of the nations. Results: In the U.S., use of spinal anesthesia for lumbar fusions would have resulted in savings of 343 million dollars in 2015. A similar reduction in cost was seen with each country studied. Additionally, spinal anesthesia was associated with 12,352 â€‹kg carbon dioxide equivalents (CO2e) while general anesthesia produced 942,872 â€‹kg CO2e. Similar reduction in carbon emissions was seen with each country studied. Discussion and conclusion: Spinal anesthesia is safe and effective for both simple and complex spine surgeries, it reduces carbon emissions, permits lower operative times, and decreases cost.

Electrical modulation of transplanted stem cells improves functional recovery in a rodent model of stroke.

Stroke is a leading cause of long-term disability worldwide, intensifying the need for effective recovery therapies. Stem cells are a promising stroke therapeutic, but creating ideal conditions for treatment is essential. Here we developed a conductive polymer system for stem cell delivery and electrical modulation in animals. Using this system, electrical modulation of human stem cell transplants improve functional stroke recovery in rodents. Increased endogenous stem cell production corresponds with improved function. Transcriptome analysis identified stanniocalcin 2 (STC2) as one of the genes most significantly upregulated by electrical stimulation. Lentiviral upregulation and downregulation of STC2 in the transplanted stem cells demonstrate that this glycoprotein is an essential mediator in the functional improvements seen with electrical modulation. Moreover, intraventricular administration of recombinant STC2 post-stroke confers functional benefits. In summation, our conductive polymer system enables electrical modulation of stem cells as a potential method to improve recovery and identify important therapeutic targets.