A Tapered Cuff Tracheal Tube Decreases the Need for Cuff Pressure Adjustment After Surgical Retraction During Anterior Cervical Spine Surgery: A Randomized Controlled, Double-Blind Trial

Background

Surgical retraction to expose the vertebrae during anterior cervical spine surgery increases tracheal tube cuff pressure and may worsen postoperative sore throat and dysphonia. This randomized double-blind study investigated the effect of cuff shape on intraoperative cuff pressure and postoperative sore throat and dysphonia.

Methods

Eighty patients were randomized to tracheal intubation with a tapered cuff or a conventional cylindrical high-volume low-pressure cuff (control) during anesthesia. Intraoperative cuff pressures were compared. The primary outcome was the incidence of pressure adjustment needed when the cuff pressure increased to > 25 mm Hg after surgical retraction. The secondary outcome was the incidence of postoperative sore throat and dysphonia.

Results

The incidence of pressure adjustment after surgical retraction was significantly lower in the tapered group than in the control group (13% vs. 48%; P = 0.001; relative risk reduction, 74%). The median [interquartile range (IQR)] cuff pressure (mm Hg) was significantly lower for the tapered cuff than for the control cuff before surgical retraction [9 (7–12) vs. 12 (10–15); P < 0.001] and after retraction [18 (15–23) vs. 25 (18–31); P = 0.007]. The median (IQR) postoperative dysphonia score assessed by a single speech-language pathologist was lower in the tapered group than in the control group [4 (3–6) vs. 5.5 (5–7); P = 0.008].

Conclusion

A tapered cuff tracheal tube decreased the need for the adjustment of cuff pressure after surgical retraction during anterior cervical spine surgery, thereby avoiding intraoperative pressure increase. It also has a better outcome in terms of dysphonia.

Clinical Trial Registration

[www.clinicaltrials.gov], identifier [NCT04591769].

Does ultrasound education improve anatomy learning? Effects of the Parallel Ultrasound Hands-on (PUSH) undergraduate medicine course

BACKGROUND

As ultrasound has become increasingly prominent in medicine, portable ultrasound is perceived as the visual stethoscope of the twenty-first century. Many studies have shown that exposing preclinical students to ultrasound training can increase their motivation and ultrasound competency. However, few studies have discussed the effect of ultrasound training on anatomy learning.

METHOD

The Parallel Ultrasound Hands-on (PUSH) course was designed to investigate whether or not ultrasonography training affects anatomy knowledge acquisition. The PUSH course included anatomical structures located in the chest and abdomen (target anatomy) and was conducted in parallel to the compulsory gross anatomy course. Learners (n = 140) voluntarily participated in this elective course (learners in the course before the midterm examination (Group 1, n = 69), or after the midterm examination (Group 2, n = 71)). Anatomy examination scores (written and laboratory tests) were utilized to compare the effects of the PUSH course.

RESULT

Group 1 obtained significantly higher written test scores on the midterm examination (mean difference [MD] = 1.5(7.6%), P = 0.014, Cohen's d = 0.43). There was no significant difference in the final examination scores between the two groups (Written Test: MD = 0.3(1.6%), P = 0.472). In Laboratory test, both mid-term (MD:0.7(2.8%), P = 0.308) and final examination (MD:0.3(1.5%), P = 0.592) showed no significant difference between two groups. Students provided positive feedback in overall learning self-efficacy after the PUSH course (Mean = 3.68, SD = ±0.56 on a 5-point Likert scale). Learning self-efficacy in the cognitive domain was significantly higher than that in the affective domain (MD = 0.58; P < 0.001) and psychomotor domain (MD = 0.12; P = 0.011).

CONCLUSION

The PUSH course featured a hands-on learning design that empowered medical students to improve their anatomy learning.

Cervical spine immobilization does not interfere with nasotracheal intubation performed using GlideScope videolaryngoscopy: a randomized equivalence trial

GlideScope-assisted nasotracheal intubation (NTI) has been proposed as an alternative to difficult orotracheal intubation for critical patients or those under cervical immobilization. We evaluated the difficulty of performing NTI using GlideScope under cervical orthosis. A total of 170 patients scheduled for elective cervical spinal surgery that required NTI were randomized to receive cervical immobilization using a cervical collar (collar group) or no cervical immobilization at all (control group) before anesthetic induction (group assignment at 1:1 ratio). All NTI during anesthetic induction were performed using the GlideScope. The primary outcome was time to intubation. The secondary outcomes were ease of intubation, including the necessity of auxiliary manipulations to assist intubation, and the nasotracheal intubation difficulty scale (nasoIDS). An exploratory analysis identified morphometric parameters as predictors of time to intubation, the necessity of auxiliary manipulations, and a nasoIDS score ≥ 4. For time to intubation, the mean difference (collar group-control) was - 4.19 s, with a 95% confidence interval (CI) of - 13.9 to 5.52 that lay within our defined equivalence margin of 16 s. Multivariate regressions precluded the association of cervical immobilization with a necessity for auxiliary manipulations (adjusted odds ratio [aOR] 0.53, 95% CI [0.26-1.09], P = 0.083) and a nasoIDS ≥ 4 (aOR 0.94 [0.84-1.05], P = 0.280). Among all morphometric parameters, the upper lip bite test class was predictive of a longer time to intubation (all analyses relative to class 1, 14 s longer for class 2, P = 0.032; 24 s longer for class 3, P = 0.070), increased necessity for auxiliary manipulation (aOR 2.29 [1.06-4.94], P = 0.036 for class 2; aOR 6.12 [1.04-39.94], P = 0.045 for class 3), and nasoIDS ≥ 4 (aOR 1.46 [1.14-1.89], P = 0.003 for class 3).The present study demonstrated that GlideScope achieved NTI in patients with or without cervical immobilization equivalently with respect to intubation time and ease.

Combined Anterior and Posterior Decompression With Fusion for Cervical Ossification of the Posterior Longitudinal Ligament

Objective:

Cervical myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) is not uncommon among Asian ethnic groups. Despite reports comparing the pros and cons of anterior- and posterior-only approaches, the optimal management remains debatable. This study aimed to evaluate the outcomes of patients who underwent a combined anterior and posterior approach, simultaneous circumferential decompression and fixation, for cervical OPLL.

Method:

The study retrospectively reviewed patients with OPLL and who underwent circumferential decompression and fixation, combined anterior corpectomy and posterior laminectomy. The clinical outcomes were evaluated by the Visual Analog Scale of neck and arm pain, the Japanese Orthopedic Association scores, Neck Disability Index, and Nurick scores at each time-point of evaluation. Radiological evaluations included plain and dynamic radiographs and computed tomography for every patient within 2 years post-operation. Subgroup analyses were further performed between the groups, with and without intra-operative cerebrospinal fluid (CSF) leakage.

Results:

A total of 41 patients completed the follow-up for more than 2 years (mean = 39.8 months) and were analyzed. Continuous-type OPLL was the most common (44%), followed by segmental (27%), mixed (22%), and localized types (7%) in the cohort. Myelopathy and all other functional outcomes improved significantly at 2 years post-operation (all p < 0.05). There were 13 (32%) patients who had intra-operative CSF leakage. At 2 years post-operation, there were no differences in the demographics, functional outcomes, and complication rates between the CSF-leakage and no-leakage groups. The CSF-leakage group had more patients with continuous-type OPLL than the no-leakage group (77 vs. 29%, p = 0.004 < 0.05). During the follow-up, there was no secondary or revision surgery for pseudomeningocele, pseudarthrosis, or other surgery-related complications.

Conclusions:

Simultaneous circumferential decompression and fixation combine the surgical benefits of sufficient decompression by the posterior approach and direct decompression of OPLL by the anterior approach. It is an effective surgical option for patients with cervical myelopathy caused by OPLL, given that myelopathy unanimously improved without neurological complications in this study. The fusion rates were high, and reoperation rates were low. Despite higher rates of CSF leakage, there were no related long-term sequelae, and minimal wound complications.

Cortical-bone-trajectory-based dynamic stabilization

BACKGROUND

Cortical-bone-trajectory (CBT) screws have demonstrated similar biomechanical strength and fusion rates as conventional pedicle screws for short-segment lumbar fusion. However, very few studies have verified the viability of CBT screws in dynamic stabilization.

OBJECTIVE

To compare the clinical outcomes of CBT-based Dynesys dynamic stabilization (CBT-DDS) with standard minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

METHODS

Consecutive patients who received CBT-DDS or MI-TLIF at L4-5 or L3-4-5 were retrospectively reviewed. All the radiological and clinical outcomes were compared between the two groups. The patient-reported outcomes (PRO) included visual analog scales of back and leg pain, Japanese Orthopaedic Association Scores, and the Oswestry Disability Index. The pre- and post-operative radiological evaluations were also reviewed.

RESULTS

A total of 60 patients (20 patients of the CBT-DDS and 40 of the MI-TLIF groups) were analyzed. The MI-TLIF group had a longer operation time (p=0.010) than the CBT-DSS group, but with similar estimated blood loss (p=0.484). Perioperative complications, including screw loosening, wound infection and radiculopathy, were similar in both groups (all p>0.05). The degree of decreased range of motion after surgery was similar between the two groups (p=0.781), and there was no pseudarthrosis in the MI-TLIF group.

CONCLUSION

Since the clinical and radiologic outcomes of CBT-DDS were similar to that of MI-TLIF in patients of L4-5 or L3-4-5 spondylosis and spondylolisthesis, CBT-DDS appeared to be a viable and effective alternative to MI-TLIF, and with less operation time and similarly limited segmental motility.

Traumatic Vertebral Fracture in a Patient With Transforaminal Lumbar Interbody Fusion: A Rare Complication

Transforaminal lumbar interbody fusion (TLIF) offers the potential benefits of anterior and posterior column decompression and fusion. Pseudarthrosis and infection are among the most common perioperative complications. Vertebral fracture after TLIF is a rare and unusual complication. A 74-year-old female underwent L3-5 TLIF for lumbar spondylolisthesis that caused back pain and neurogenic claudication. She recovered well after surgery. However, she subsequently experienced progressive back pain and recurrent claudication after a fall. Elongated anterior-posterior length of the L5 body with progressive L5-S1 listhesis was observed in the serial radiographic follow-ups. The CT scan revealed complicated fracture lines crossing the L5 body. Further extended fixation was performed for decompression and reconstruction of the lumbosacral alignment. Although vertebral fracture after TLIF is a rare complication, a high index of suspicion is the key to early diagnosis, preferably with CT scans, for patients with traumatic accidents after TLIF surgery.

Comparison of prognosis predictive value of 4 disease severity scoring systems in patients with acute respiratory failure in intensive care unit: A STROBE report

Various disease severity scoring systems were currently used in critically ill patients with acute respiratory failure, while their performances were not well investigated.The study aimed to investigate the difference in prognosis predictive value of 4 different disease severity scoring systems in patients with acute respiratory failure.With a retrospective cohort study design, adult patients admitted to intensive care unit (ICU) with acute respiratory failure were screened and relevant data were extracted from an open-access American intensive care database to calculate the following disease severity scores on ICU admission: acute physiology score (APS) III, Sequential Organ Failure Assessment score (SOFA), quick SOFA (qSOFA), and Oxford Acute Severity of Illness Score (OASIS). Hospital mortality was chosen as the primary outcome. Multivariable logistic regression analyses were performed to analyze the association of each scoring system with the outcome. Receiver operating characteristic curve analyses were conducted to evaluate the prognosis predictive performance of each scoring system.A total of 4828 patients with acute respiratory failure were enrolled with a hospital mortality rate of 16.78%. APS III (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.02-1.03), SOFA (OR 1.15, 95% CI 1.12-1.18), qSOFA (OR 1.26, 95% CI 1.11-1.42), and OASIS (OR 1.06, 95% CI 1.05-1.08) were all significantly associated with hospital mortality after adjustment for age and comorbidities. Receiver operating characteristic analyses showed that APS III had the highest area under the curve (AUC) (0.703, 95% CI 0.683-0.722), and SOFA and OASIS shared similar predictive performance (area under the curve 0.653 [95% CI 0.631-0.675] and 0.664 [95% CI 0.644-0.685], respectively), while qSOFA had the worst predictive performance for predicting hospital mortality (0.553, 95% CI 0.535-0.572).These results suggested the prognosis predictive value varied among the 4 different disease severity scores for patients admitted to ICU with acute respiratory failure.

A novel approach: Simulating multiple simultaneous encounters to assess multitasking ability in emergency medicine

Study objective

The purpose of this feasibility study is to develop and validate a new assessment tool and scoring system for multitasking competency for physicians in-training in a timed simulated setting. The multitasking competency includes ability to appropriately prioritize and implement tasks for different patients who present simultaneously.

Methods

We designed three single task stations with different levels of difficulty and priority. These skill stations were then combined to create a multitasking simulation scenario. Skill checklists and the global rating scale were utilized to assess the participants’ performance. A multitasking score, multitasking index, and priority score were developed to measure the multitasking ability of participants.

Results

Thirty-three first-year postgraduate physicians were recruited for this prospective study. The total performance scores were significantly higher for the single-tasking stations than for the multitasking scenario. In terms of the time needed to complete the tasks, the participants spent more time on the multitasking scenario than on the single-tasking scenario. There were significant correlations between the global rating scale and the multitasking score (rho = 0.693, p < 0.001) and between the global rating scale and the multitasking index (rho = 0.515, p < 0.001). The multitasking score, multitasking index, and priority score did not have any significant correlations with the total single-tasking score.

Conclusion

We demonstrated that the use of a simulated multitasking scenario could be an effective method of assessing multitasking ability and allow assessors to offer better quality feedback.

Cervical disc arthroplasty for Klippel-Feil syndrome

OBJECTIVE

Klippel-Feil syndrome (KFS) is a congenital musculoskeletal condition characterized by improper segmentation of the cervical spine. This study aimed to evaluate outcomes of KFS patients who underwent cervical disc arthroplasty (CDA).

METHODS

Consecutive patients who underwent anterior cervical surgery were retrospectively reviewed. Those patients with KFS who received discectomy adjacent to the congenitally fused vertebral segments were extracted and grouped into either the fusion or the CDA group. Clinical and radiological evaluations included visual analog scales, Neck Disability Index (NDI), Japanese Orthopedic Association (JOA) scores, C2-7 range of motion (ROM), C2-7 Cobb angle, C2-7 sagittal vertical axis (SVA), and T1-slope.

RESULTS

Among 2320 patients, there were 41 with KFS (prevalence = 1.77%), who were younger than the entire cohort (53.3 vs 56.4 years). Thirty KFS patients had adjacent discs and were grouped into the CDA and fusion groups (14 vs 16). Type-I KFS with C3-4 involvement was the most common for both groups (92.8% vs 81.2% with 57% vs 50%, respectively). Post-operation, both groups demonstrated improvement of all the patient reported outcomes. The C2-7 ROM significantly decreased in the fusion group than that of pre-operation (12.8 ± 6° vs 28.1 ± 11.5°). In contrast, the CDA group successfully preserved C2-7 and segmental ROM without additional complications.

CONCLUSIONS

KFS is rare (prevalence = 1.77%) among cervical spine surgery patients, and it rarely affects the overall cervical spinal alignment, except that it decreases segmental mobility. CDA is a feasible option for KFS because it not only avoids long-segment fusion but also preserves segmental and global mobility.

Anti-Inflammatory Effect of Charantadiol A, Isolated from Wild Bitter Melon Leaf, on Heat-Inactivated Porphyromonas gingivalis-Stimulated THP-1 Monocytes and a Periodontitis Mouse Model

Porphyromonas gingivalis has been identified as one of the major periodontal pathogens. Activity-directed fractionation and purification processes were employed to identify bioactive compounds from bitter melon leaf. Ethanolic extract of bitter melon leaf was separated into five subfractions by open column chromatography. Subfraction-5-3 significantly inhibited P. gingivalis-induced interleukin (IL)-8 and IL-6 productions in human monocytic THP-1 cells and then was subjected to separation and purification by using different chromatographic methods. Consequently, 5β,19-epoxycucurbita-6,23(E),25(26)-triene-3β,19(R)-diol (charantadiol A) was identified and isolated from the subfraction-5-3. Charantadiol A effectively reduced P. gingivalis-induced IL-6 and IL-8 productions and triggered receptors expressed on myeloid cells (TREM)-1 mRNA level of THP-1 cells. In a separate study, charantadiol A significantly suppressed P. gingivalis-stimulated IL-6 and tumor necrosis factor-α mRNA levels in gingival tissues of mice, confirming the inhibitory effect against P. gingivalis-induced periodontal inflammation. Thus, charantadiol A is a potential anti-inflammatory agent for modulating P. gingivalis-induced inflammation.

Correlation of bone density to screw loosening in dynamic stabilization: an analysis of 176 patients

Although osteoporosis has negative impacts on lumbar fusion, its effects on screw loosening in dynamic stabilization remain elusive. We aimed to correlate bone mineral density (BMD) with screw loosening in Dynesys dynamic stabilization (DDS). Consecutive patients who underwent 2- or 3-level DDS for spondylosis, recurrent disc herniations, or low-grade spondylolisthesis at L3-5 were retrospectively reviewed. BMD was assessed by the Hounsfield Unit (HU) in vertebral bodies (VB) and pedicles with and without cortical bone (CB) on pre-operative computed tomography (CT). Screw loosening was assessed by radiographs and confirmed by CT. HU values were compared between the loosened and intact screws. 176 patients and 918 screws were analyzed with 78 loosened screws found in 36 patients (mean follow-up: 43.4 months). The HU values of VB were similar in loosened and intact screws (p = 0.14). The HU values of pedicles were insignificantly less in loosened than intact screws (including CB: 286.70 ± 118.97 vs. 297.31 ± 110.99, p = 0.45; excluding CB: 238.48 ± 114.90 vs. 240.51 ± 108.91, p = 0.88). All patients had clinical improvements. In conclusion, the HU values, as a surrogate for BMD, were unrelated to screw loosening in DDS. Therefore, patients with compromised BMD might be potential candidates for dynamic stabilization rather than fusion.

Late complication of cervical disc arthroplasty: heterotopic ossification causing myelopathy after 10 years. Illustrative case

BACKGROUND

Heterotopic ossification (HO) is a well-documented complication of cervical disc arthroplasty (CDA), although it rarely causes adverse clinical effects. Despite high-grade HO possibly limiting segmental mobility, it is reportedly seldom associated with symptoms.

OBSERVATIONS

The authors report a case of a 46-year-old male patient who underwent hybrid CDA and anterior cervical discectomy and fusion for 3-level cervical disc herniation that caused myeloradiculopathy. The surgery was successful; the patient experienced nearly complete recovery postoperatively. The follow-up images, including computed tomography and magnetic resonance imaging scans, showed satisfactory decompression at the indexed levels without residual osteophytes or ossification of the posterior longitudinal ligament. However, 10 years later, the patient presented with symptomatic compressive myelopathy caused by severe HO that prompted a secondary surgery.

LESSONS

Although it is generally reported in the literature that HO is clinically innocuous, in this patient, it gradually and progressively developed and caused myelopathy, requiring a secondary surgery. Symptomatic HO can be expected over time, and patients with a high risk of HO deserve long-term follow-up after CDA. Further investigations are warranted to corroborate these risk factors, including multilevel calcified disc herniation, severe spondylosis, and suboptimal placement of the device during primary CDA surgery.

Why do pre-clinical medical students learn ultrasound? Exploring learning motivation through ERG theory

BACKGROUND

In recent years, point-of-care ultrasound (POCUS) has become an essential field of medical education. Bedside ultrasound has become a necessary skill for clinical physicians. Previous studies have already discussed the importance of advancements in ultrasound education. However, learning motivations for ultrasound education have seldom been analyzed in the literature. For medical students, learning ultrasound could have a relevance for their future career. The Existence, Relatedness and Growth (ERG) theory extended Maslow's hierarchy of needs through these three concepts. This theory has been widely used in the workplace to analyze employee job performance but has not yet been applied in medical education. In this study ERG theory was applied to analyze pre-clinical medical students' learning motivation toward ultrasound education.

METHOD

This mixed method study used online questionnaires consisting of open-ended questions as a data collection tool, and based on these results, both qualitative and quantitative analysis were conducted. Participants answered a series of neutral and open-ended questions regarding their motivations to learn ultrasonography. After data collection, a three-step analysis was conducted based on the grounded theory approach. Finally, the results of the thematic coding were used to complete additional quantitative analysis.

RESULTS

The study involved 140 pre-clinical medical students, and their responses fell into 13 specific categories. The analysis demonstrated that students' motivations toward ultrasound education were unbalanced across the three ERG domains (F = 41.257, p < .001). Pairwise comparisons showed that students mentioned existence motivation (MD = 39.3%; p < .001) and growth motivation (MD = 40.7%; p < .001) more frequently than relatedness motivation. However, there was no significant difference between existence motivation and growth motivation (MD = - 1.4%; p = .830).

CONCLUSION

The results revealed that students placed a high value on existence and growth needs rather than relatedness based on the survey. In addition, the findings suggest that ERG theory can be a useful tool to conduct medical education motivation analysis.

Effects of a simulation-based education programme on delirium care for critical care nurses: A randomized controlled trial

AIMS

To evaluate the effects of a simulation-based education programme on critical care nurses' knowledge, confidence, competence and clinical performance in providing delirium care.

DESIGN

Single-blinded randomized controlled trial.

METHODS

Registered nurses who work in intensive care units were recruited from a university-affiliated acute major metropolitan teaching hospital. The intervention group received: (i) five online-learning delirium care videos, (ii) one face-to-face delirium care education session and (iii) a simulation-based education programme with a role-play scenario-based initiative and an objective structured clinical examination. The control group received only online videos which were the same as those provided to the intervention group. Delirium care knowledge, confidence, competence, and clinical performance as outcomes were collected at: baseline, immediately after intervention, and within 6 weeks post-intervention to test whether there were any changes and if they were sustained over time. Data were collected between 2 October and 29 December 2020. The repeated-measures analysis of variance was used to examine for changes in delirium care knowledge, confidence, and competence within groups.

RESULTS

Seventy-two critical care nurses participated with 36 each allocated to the intervention group and control group. No statistically significant difference was observed between the two groups in outcome variables at 6 weeks post-intervention. In the intervention group, significant within-group changes were observed in terms of delirium care knowledge, confidence, and competence over time. By contrast, no significant changes were observed in outcome measures over time in the control group.

CONCLUSION

The simulation-based education programme is an effective and feasible strategy to improve delirium care by enhancing the knowledge, confidence, competence and clinical performance of critical care nurses.

IMPACT

Our findings provide evidence regarding the development and implementation of a simulation-based education programme in hospitals for health professional education in Taiwan.

Cloward’s approach for Pancoast neurogenic tumors: illustrative cases

BACKGROUND

Pancoast tumors are a wide range of tumors located in the apex of the lung. Traditional surgery for Pancoast neurogenic tumors frequently involves extensive approaches, whether anterior or posterior or a combination, in which osteotomies are sometimes required. In this study, the authors proposed a less invasive surgical strategy using the standard Cloward’s approach for complete resection of a schwannoma arising from the T1 nerve root.

OBSERVATIONS

Two patients, each harboring a large T1 tumor, one on each side, underwent Cloward’s approach with and without thoracoscopic surgery. Both patients had complete resection of the tumor. Considering the benign and encapsulated nature of neurogenic tumors, Cloward’s approach under neuromonitoring, which is a common procedure for anterior cervical discectomy for most neurosurgeons, is a safe and less invasive alternative for Pancoast neurogenic tumors. For patients whose tumor cannot be removed completely via Cloward’s approach, video-assisted thoracoscopic surgery is a viable backup plan with minimal invasiveness.

LESSONS

Cloward’s approach is a viable option for Pancoast neurogenic tumors.

Practice and outcomes of airway management in patients with cervical orthoses

BACKGROUND/PURPOSE

Increasing evidence indicates an association of video laryngoscopy with the success rate of airway management in patients with neck immobilization. Nevertheless, clinical practice protocols for tracheal intubation in patients immobilized using various types of cervical orthoses and the outcomes remain unclear.

METHODS

We retrospectively assessed the tracheal intubation techniques selected for patients immobilized using cervical orthoses from 2015 to 2018. The endpoints were the intubation outcomes of the different techniques and the factors associated with the selection of the technique.

RESULTS

We included 218 patients, 118 of whom wore halo vest braces (halo vest group) and 100 wore cervical collars (collar group). GlideScope video laryngoscopy (GVL) and fiberoptic bronchoscopy (FOB) were the initial intubation methods in 98 and 120 patients, respectively. GVL had a higher first-attempt success rate than did FOB in the collar group (p = 0.002) but not in the halo vest group (p = 0.522). GVL was associated with a lower risk of episodes of SaO₂< 90% (adjusted relative risk [aRR], 0.11; 95% CI, 0.02-0.67; p = 0.016) and shorter intubation time (aRR, -3.52; 95% CI, -4.79∼-2.25; p < 0.001) in the collar group. However, in the halo vest group, more frequent requirement of a rescue technique (p = 0.002) and necessity of patient awakening (p = 0.001) was noted when GVL was used. Use of the halo vest brace and noting of severe cord compression were independent predictors of the initial selection of FOB.

CONCLUSION

Caution should be exercised when using GVL for tracheal intubation in patients immobilized using halo vest braces.

Postoperative Sore Throat Helps Predict Swallowing Disturbance on Postoperative Day 30 of Anterior Cervical Spine Surgery: A Secondary Exploratory Analysis of a Randomized Clinical Trial of Tracheal Intubation Modes

Nasotracheal intubation benefits dysphonia recovery after anterior cervical spine surgery (ACSS). The aim of the present study was to investigate the effect of tracheal intubation modes on post-ACSS swallowing function and identify factors associated with deglutition on postoperative day 30 (POD 30). Adult patients were randomized to receive either nasotracheal or orotracheal intubation during surgery. A numerical rating scale (NRS) was used to assess postoperative sore throat, and the Bazaz grading system was used to assess the severity of swallowing disturbance. The primary endpoints were the effect of tracheal intubation modes on postoperative sore throat and deglutition. Thereafter, we further elucidated the predictors of swallowing disturbance on POD 30. Postoperative sore throat and swallowing disturbance did not differ between the nasotracheal and orotracheal intubation groups. A secondary dataset analysis revealed that among 108 patients with complete follow-up until POD 30, 71 (65.7%) presented complete recovery without swallowing disturbance, whereas 37 (34.3%) presented varying degrees of swallowing disturbance. Receiver operating characteristic curve analysis indicated that the NRS score for sore throat predicted a swallowing disturbance-free status on POD 30. The optimal cutoff values were ≤ 4 and ≤ 2 on PODs 1 and 2, respectively. The adjusted odds ratio (OR) for independent predictors was a sore throat NRS score of ≤ 4 on POD 1 (OR 3.2; 95% CI 1.29-7.89; P = 0.012) and score of ≤ 2 on POD 2 (OR 6.67; 95% CI 2.41-18.47; P < 0.001). Therefore, tracheal intubation mode did not affect the incidence of post-ACSS swallowing disturbance, and the severity of sore throat on PODs 1 and 2 could predict a swallowing disturbance-free status on POD 30.The trial was registered at clinicaltrials.gov (Trial No. NCT03240042, date of registration 10/17/2017).

Minocycline exhibits synergism with conditioned medium of bone marrow mesenchymal stem cells against ischemic stroke

Several lines of evidence show that a conditioned medium of bone marrow mesenchymal stem cells (BM-MSCcm) improve functional recovery after ischemic stroke but do not reduce ischemic lesions. It is important to develop a treatment strategy that can exhibit a synergistic effect with BM-MSCcm against ischemic stroke. In this study, the effect of BM-MSCcm and/or minocycline was examined in culture and in a middle cerebral artery occlusion (MCAo) animal model. In neuron-glial cultures, BM-MSCcm and combined treatment, but not minocycline, effectively increased neuronal connection and oligodendroglial survival. In contrast, minocycline and combined treatment, but not BM-MSCcm, reduced toxin-induced free radical production in cultures. Either minocycline or BM-MSCcm, or in combination, conferred protective effects against oxygen glucose deprivation-induced cell damage. In an in vivo study, BM-MSCcm and minocycline were administered to rats 2 h after MCAo. Monotherapy with BM-MSCcm or minocycline after ischemic stroke resulted in 9.4% or 17.5% reduction in infarction volume, respectively, but there was no significant difference. Interestingly, there was a 33.9% significant reduction in infarction volume by combined treatment with BM-MSCcm and minocycline in an in vivo study. The combined therapy also significantly improved grasping power, which was not altered by monotherapy. Furthermore, combined therapy increased the expression of neuronal nuclei in the peri-infarct area and hippocampus, and concurrently decreased the expression of ED1 in rat brain and the peri-infarct zone. Our data suggest that minocycline exhibits a synergistic effect with BM-MSCcm against ischemic stroke not only to improve neurological functional outcome but also to reduce cerebral infarction.

Stem cell transplantation and/or adenoviral glial cell line-derived neurotrophic factor promote functional recovery in hemiparkinsonian rats

BACKGROUND

Parkinson’s disease (PD) is a neurological disorder characterized by the progressive loss of midbrain dopamine (DA) neurons. Bone marrow mesenchymal stem cells (BMSCs) can differentiate into multiple cell types including neurons and glia. Transplantation of BMSCs is regarded as a potential approach for promoting neural regeneration. Glial cell line-derived neurotrophic factor (GDNF) can induce BMSC differentiation into neuron-like cells. This work evaluated the efficacy of nigral grafts of human BMSCs (hMSCs) and/or adenoviral (Ad) GDNF gene transfer in 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian rats.

AIM

To evaluate the efficacy of nigral grafts of hMSCs and/or Ad-GDNF gene transfer in 6-OHDA-lesioned hemiparkinsonian rats.

METHODS

We used immortalized hMSCs, which retain their potential for neuronal differentiation. hMSCs, preinduced hMSCs, or Ad-GDNF effectively enhanced neuronal connections in cultured neurons. In vivo, preinduced hMSCs and/or Ad-GDNF were injected into the substantia nigra (SN) after induction of a unilateral 6-OHDA lesion in the nigrostriatal pathway.

RESULTS

Hemiparkinsonian rats that received preinduced hMSC graft and/or Ad-GDNF showed significant recovery of apomorphine-induced rotational behavior and the number of nigral DA neurons. However, DA levels in the striatum were not restored by these therapeutic treatments. Grafted hMSCs might reconstitute a niche to support tissue repair rather than contribute to the generation of new neurons in the injured SN.

CONCLUSION

The results suggest that preinduced hMSC grafts exert a regenerative effect and may have the potential to improve clinical outcome.

Neuroprotection in the Acute Stage Enables Functional Recovery Following Repair of Chronic Cervical Root Transection After a 3-Week Delay

BACKGROUND

Preganglionic cervical root transection (PCRT) is the most severe type of brachial plexus injury. In some cases, surgical procedures must be postponed for ≥3 wk until electromyographic confirmation. However, research works have previously shown that treating PCRT after a 3-wk delay fails to result in functional recovery.

OBJECTIVE

To assess whether the immunosuppressive drug sirolimus, by promoting neuroprotection in the acute phase of PCRT, could enable functional recovery in cases of delayed repair.

METHODS

First, rats received a left 6th to 8th cervical root transection, after which half were administered sirolimus for 1 wk. Markers of microglia, astrocytes, neurons, and autophagy were assessed at days 7 and 21. Second, animals with the same injury received nerve grafts, along with acidic fibroblast growth factor and fibrin glue, 3 wk postinjury. Sirolimus was administered to half of them for the first week. Mechanical sensation, grasping power, spinal cord morphology, functional neuron survival, nerve fiber regeneration, and somatosensory-evoked potentials (SSEPs) were assessed 1 and 23 wk postinjury.

RESULTS

Sirolimus was shown to attenuate microglial and astrocytic proliferation and enhance neuronal autophagy and survival; only rats treated with sirolimus underwent significant sensory and motor function recovery. In addition, rats who achieved functional recovery were shown to have abundant nerve fibers and neurons in the dorsal root entry zone, dorsal root ganglion, and ventral horn, as well as to have SSEPs reappearance.

CONCLUSION

Sirolimus-induced neuroprotection in the acute stage of PCRT enables functional recovery, even if surgical repair is performed after a 3-wk delay.

Establishment of an Immunocompetent Metastasis Rat Model with Hepatocyte Cancer Stem Cells

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality. Cancer stem cells (CSCs) are responsible for the maintenance, metastasis, and relapse of various tumors. The effects of CSCs on the tumorigenesis of HCC are still not fully understood, however. We have recently established two new rat HCC cell lines HTC and TW-1, which we isolated from diethylnitrosamine-induced rat liver cancer. Results showed that TW-1 expressed the genetic markers of CSCs, including CD133, GSTP1, CD44, CD90, and EpCAM. Moreover, TW-1 showed higher tolerance to sorafenib than HTC did. In addition, tumorigenesis and metastasis were observed in nude mice and wild-type rats with TW-1 xenografts. Finally, we combined highly expressed genes in TW-1/HTC with well-known biomarkers from recent HCC studies to predict HCC-related biomarkers and able to identify HCC with AUCs > 0.9 after machine learning. These results indicated that TW-1 was a novel rat CSC line, and the mice or rat models we established with TW-1 has great potential on HCC studies in the future.

Differential time-lag effects of ambient PM2.5 and PM2.5-bound PAHs on asthma emergency department visits

Epidemiological studies have suggested the effects of ambient fine particles (PM_2.5) on asthma, but the effects of specific components of PM_2.5 on asthma remain to be explored. Here, we studied the effect of PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs) on asthma acute exacerbation. The data on daily counts of emergency room visits (ERVs) were obtained from Wan Fang Medical Center, Taipei, Taiwan, from 2012 to 2015. The daily concentrations of PM_2.5 and pollutant gases were obtained from a local air quality monitoring station. The levels of PM_2.5-bound PAH were estimated by an established grid-scale model. Relative risks for ERVs as the increase in the level of ambient pollutants were calculated by using a generalized additive model of Poisson regression. In the present study, we observed statistically significant positive associations between PM_2.5 and asthma ERVs for all age groups. PM_2.5-bound PAH was also associated with asthma ERVs for all age groups. In the adult subgroup analysis, there was a significant association between PM_2.5-bound PAH and asthma ERVs at lags 1 and 2 (RR 1.289, 95% CI 1.050-1.582 and RR 1.242, 95% CI 1.039-1.485). The impacts of air pollution on the risk of pediatric asthma ERV were found to be significant for PM_2.5 at lag day 0 (RR 1.310, 95% CI 1.069-1.606). Moreover, pediatric asthma ERVs were significantly associated with the levels of PM_2.5-bound PAH at lag 1 and 2 days (RR 1.576, 95% CI 1.371-1.810 and RR 1.426, 95% CI 1.265-1.607). The study provides evidence that PM_2.5-bound PAHs were associated with an increased risk of asthma attacks. Our data further suggested that traffic exhaust is a primary source of PM_2.5-bound PAHs.

Impact of virtual reality anatomy training on ultrasound competency development: A randomized controlled trial

PURPOSE

The use of Virtual Reality (VR) in health professions education has increased dramatically in recent years, yet there is limited evidence of its impact on educational outcomes. The purpose of the study was to assess the impact of VR anatomy instruction on the ultrasound competency of novice learners participating in a ultrasonography workshop.

METHOD

We designed a VR-enhanced ultrasonography training program and utilized a plane transection tool to interact with a three-dimensional (3D) VR model of the human body which facilitated the 3D conceptualization of the spatial relationship of anatomical structures, leading to faster and better development of ultrasonographic competency. This was a randomized control study which enrolled third-year medical students (n = 101) without previous exposure to formal or informal ultrasonography training. The participants were randomly divided into an intervention and control group. We assessed participants' competency through ultrasound performance stations on live subjects, we also measured anatomical and ultrasound image identification ability using multiple choice tests.

RESULT

Participants in the intervention group (median = 16; interquartile 13 to 19) had significantly higher scores in ultrasonography task performance tests than the control group (median = 10; interquartile 7 to 14; Mann-Whitney U = 595; P < 0.01). In sub-group analysis, the intervention group performed significantly better in the six out of ten ultrasound tasks. Participants in the intervention group also had greater improvement in ultrasonographic image identification MCQ tests than the control group (Mann-Whitney U = 914; P < 0.05).

CONCLUSION

This study suggests that VR-enhanced anatomical training could be of significant benefit in ultrasonography training by promoting a better understanding of the spatial relationships of anatomical structures and the development of early psychomotor skills transferable to the handling of ultrasonographic probes.

The Effect of T1-Slope in Spinal Parameters After Cervical Disc Arthroplasty

BACKGROUND

Although patients with cervical kyphosis are not ideal candidates for cervical disc arthroplasty (CDA), there is a paucity of data on patients with a straight or slightly lordotic neck.

OBJECTIVE

To correlate cervical lordosis, T1-slope, and clinical outcomes of CDA.

METHODS

The study retrospectively analyzed 95 patients who underwent 1-level CDA and had 2-yr follow-up. They were divided into a high T1-slope (≥28°) group (HTSG, n = 45) and a low T1-slope (<28°) group (LTSG, n = 50). Cervical spinal alignment parameters, including T1-slope, cervical lordosis (C2-7 Cobb angle), and segmental mobility (range of motion [ROM]) at the indexed level, were compared. The clinical outcomes were also assessed.

RESULTS

The mean T1-slope was 28.1 ± 7.0°. After CDA, the pre- and postoperative segmental motility remained similar and cervical lordosis was preserved. All the clinical outcomes improved after CDA. The HTSG were similar to the LTSG in age, sex, segmental mobility, and clinical outcomes. However, the HTSG had higher cervical lordosis than the LTSG. Furthermore, the LTSG had increased cervical lordosis (ΔC2-7 Cobb angle), whereas the HTSG had decreased lordosis after CDA. Patients of the LTSG, who had more improvement in cervical lordosis, had a trend toward increasing segmental mobility at the index level (ΔROM) than the HTSG.

CONCLUSION

In this series, T1-slope correlated well with global cervical lordosis but did not affect the segmental mobility. After CDA, the changes in cervical lordosis correlated with changes in segmental mobility. Therefore, segmental lordosis should be cautiously preserved during CDA as it could determine the mobility of the disc.