Risk factors for new vertebral compression fracture after vertebroplasty and efficacy of osteoporosis treatment: A STROBE-compliant retrospective study.

Vertebroplasty (VP) effectively treats vertebral compression fractures (VCFs). However, the issue of secondary new VCFs (SNVCFs) after VP is yet to be addressed. Therefore, identification of risk factors for SNVCFs after VP may aid the development of strategies to minimize SNVCF risk. This study aimed to retrospectively evaluate risk factors for SNVCFs after VP, including those associated with the type of anti-osteoporotic treatment administered after VP. Data from 128 patients who underwent single-level VP were collected and reviewed. Patients were divided into 2 groups: those with (n = 28) and without (n = 100) SNVCF within 1 year of VP. We collected the following patient data: age, sex, site of compression fracture, medical history, bone mineral density (BMD), history of long-term steroid use, history of osteoporosis drug use, duration between fracture and VP, VP implementation method (unilateral or bilateral), cement usage in VP, cement leakage into the disc, compression ratio before VP, pre- and postoperative recovery ratio of the lowest vertebral body height, and kyphotic angle of fractured vertebrae. These data were analyzed to identify factors associated with SNVCFs after VP and to investigate the effects of the type of anti-osteoporotic treatment administered for SNVCFs. SNVCFs occurred in 28 patients (21.9%) within 1 year of VP. Logistic regression analysis identified BMD, cement leakage into the disc, and long-term steroid use to be significantly associated with the occurrence of SNVCFs. The group treated with zoledronate after VP had a significantly reduced SNVCF incidence compared with the group treated with calcium (P < .001). In addition, the zoledronate group had a lower SNVCF incidence compared with the groups treated with alendronate (P = .05), selective estrogen receptor modulators (P = .26), or risedronate (P = .22). This study showed that low BMD, presence of an intradiscal cement leak, and long-term steroid use were risk factors for developing SNVCFs following VP. Additionally, among osteoporosis treatments prescribed for VP, zoledronate may be the preferred choice to reduce the risk of SNVCFs.

Tongue retraction using a McIvor blade improves airway condition during fiberoptic intubation: a randomized controlled trial.

Airway clearance is crucial for successful fiberoptic intubation. We hypothesized that tongue retraction using a McIvor blade could facilitate fiberoptic intubation. This randomized clinical trial aimed to compare intubation time and airway condition between the jaw thrust maneuver and tongue retraction with the McIvor blade during fiberoptic intubation. Ninety-four adult patients scheduled for elective surgery were randomly assigned to one of two groups. During fiberoptic intubation, airway clearance was secured by applying the jaw-thrust maneuver (J group) or by tongue retraction using the McIvor blade (M group). We assessed the total intubation time, number of attempts for tube advancement, and airway clearance at the soft palate and epiglottis levels. The total intubation time was significantly shorter in the M group than in the J group (p = 0.035). The number of attempts to advance the tube was significantly lower in the M group (p = 0.033). Airway clearance at the soft palate level was significantly better in the M group than in the J group (p = 0.027). Retracting the tongue with the McIvor blade demonstrated a better condition for fiberoptic intubation and shortened total intubation time compared with the jaw-thrust maneuver.Clinicalregistiration: CRIS; http://cris.nih.go.kr (KCT0002392) registered 28/07/2017.

Erector spinae plane block in laparoscopic colorectal surgery for reducing opioid requirement and facilitating early ambulation: a double-blind, randomized trial.

Various techniques have been formulated to reduce pain and ensure early recovery after surgery, as these are major concerns among surgeons, anesthesiologists, and patients. Erector spinae plane block (ESPB), the injection of local anesthetic into the fascial plane, is a simple and novel analgesia technique widely used due to its minimal risk of complications. ESPB has been tried in various surgeries; however, no study has reported its use in colorectal surgery. This study investigated whether ESPB could promote early recovery following laparoscopic colorectal surgery (LCS) by reducing opioid consumption and pain intensity. After randomization into the ESPB or control groups, an ultrasound-guided ESPB was performed at the thoracic 10th-11th level with 40 mL of 0.25% bupivacaine or normal saline. The ESPB group used less fentanyl during the initial 24 h after surgery (P = 0.004) and experienced less pain (P < 0.05 at all-time points) than the control group. The time to the first ambulation and the length of hospital stay were shorter in the ESPB group than in the control group (P = 0.015 and P = 0.008, respectively). In conclusion, ESPB could promote early recovery by reducing opioid consumption and pain intensity in patients receiving LCS.

Preoperative Serum Alkaline Phosphatase and Neurological Outcome of Cerebrovascular Surgery.

This study evaluated the relationship between the preoperative alkaline phosphatase (ALP) level and major postoperative neurological complications in patients undergoing cerebral bypass surgery. This was a retrospective analysis of a prospective database of all patients undergoing cerebral bypass surgery after a diagnosis of cerebrovascular stenosis or occlusion between May 2003 and August 2017. The patients were divided into tertiles based on serum alkaline phosphatase (ALP) levels (low: <63, intermediate: 63~79, and high: ALP > 79 IU/mL). The incidence of neurological events according to ALP level was analyzed. The study analyzed 211 cases. The incidence of acute infarction was highest in the third serum ALP tertile (5.7% vs. 2.9% vs. 16.9% in the first, second, and third tertile, respectively, p = 0.007). Logistic regression analysis showed that the third tertile of serum ALP was an independent predictor of acute cerebral infarction (odds ratio 3.346, 95% confidence interval 1.026−10.984, p = 0.045). On Kaplan−Meier time-to-event curves, the incidence of acute infarction increased significantly with ALP (log rank = 0.048). Preoperative serum ALP level can be used as a biomarker to predict acute cerebral infarction in patients undergoing cerebral bypass surgery for vascular stenosis or occlusion.

Comparison of a New Video Intubation Stylet and McGrath® MAC Video Laryngoscope for Intubation in an Airway Manikin with Normal Airway and Cervical Spine Immobilization Scenarios by Novice Personnel: A Randomized Crossover Study.

The use of both a video laryngoscope and a video intubation stylet, compared with the use of a direct laryngoscope, is not only easier to learn but also associated with a higher success rate in performing endotracheal intubation for novice users. However, data comparing the two video devices used by novice personnel are rarely found in literature. Nondelayed intubation is an important condition to determine the prognosis in critically ill patients; hence, exploring intubation performance in various situations is of clinical significance. This study is aimed at comparing a video stylet and a video laryngoscope for intubation in an airway manikin with normal airway and cervical spine immobilization scenarios by novice personnel. We compared the performance of intubation by novices between the Aram Video Stylet and the McGrath® MAC video laryngoscope in an airway manikin. Thirty medical doctors with minimal experience of endotracheal intubation attempted intubation on a manikin five times with each device in each setting (normal airway and cervical spine immobilization scenarios). The order of use of the devices in each scenario was randomized for each participant. In the normal airway scenario, the Aram stylet showed a significantly higher rate of successful intubation than the McGrath® (98.7% vs. 92.0%; odds ratio (95% CI): 6.4 (1.4-29.3); p = 0.006). The intubation time was shorter using the Aram Stylet than that using the McGrath® video laryngoscope (p < 0.001). In the cervical immobilization scenario, successful endotracheal intubation was also more frequent using the Aram stylet than with the McGrath® (96.0% vs. 87.3%; odds ratio (95% CI): 3.5 (1.3-9.0); p = 0.007). The Aram Stylet intubation time was shorter (p < 0.001). In novice personnel, endotracheal intubation appears to be more successful and faster using the Aram Video Stylet than the McGrath® MAC video laryngoscope.

The Effects of Propofol or Dexmedetomidine Sedation on Postoperative Recovery in Elderly Patients Receiving Lower Limb Surgery under Spinal Anesthesia: A Retrospective Propensity Score-Matched Analysis.

Propofol and dexmedetomidine are the two most popular intravenous sedatives during anesthesia. However, data comparing the effects of these two sedatives during spinal anesthesia on postoperative recovery are still insufficient. We retrospectively analyzed the medical records of patients aged ≥65 years who underwent orthopedic surgery under spinal anesthesia between March 2012 and February 2017. The patients were allocated into two groups according to the intraoperative sedatives: the propofol group and dexmedetomidine group. We analyzed the incidence of postoperative delirium, analgesic requirement, and rescue anti-emetic treatment. A total of 1045 patients were included in the analysis. After propensity score matching with the propofol group, the dexmedetomidine group showed a lower incidence of postoperative delirium (odds ratio, 0.19; 95% CI, 0.07-0.56; p = 0.011). Postoperative analgesic and anti-emetic requirement were not significantly different between the two groups (p = 0.156 and 0.245, respectively). Multivariate logistic regression analysis revealed that intraoperative sedation, age, preoperative albumin level, and hip surgery were significantly associated with the incidence of postoperative delirium. This study showed that intraoperative dexmedetomidine sedation under spinal anesthesia during lower limb surgery is associated with a lower incidence of postoperative delirium compared with propofol sedation.

The 5% Lidocaine Patch for Decreasing Postoperative Pain and Rescue Opioid Use in Sternotomy: A Prospective, Randomized, Double-blind Trial.

PURPOSE: Poststernotomy pain (PSP), a primary concern after sternotomy, can negatively affect patients' satisfaction with surgery and quality of life. Many clinical trials have been conducted to examine the usefulness of lidocaine patches (LPs) for postoperative pain control for multiple types of surgery; however, the results of these trials are inconsistent. In addition, little is known about the use of LPs after cardiac procedures that require sternotomy. This prospective, double-blind, placebo-controlled trial aimed to determine the efficacy of the 5% LP application at the sternotomy site for reducing PSP and rescue opioid consumption. METHODS: The patients were randomly assigned to receive either the 5% LP or the placebo patch on each side of the incision site immediately after the surgery. The intensity of pain at 6, 12, 24, and 48 h after the patch application; the total dose of rescue opioids; incidence of nausea, vomiting, and sleep disturbance; and use of antiemetics were compared between the 2 groups. FINDINGS: Fifty-seven (31 in the LP group and 26 in the placebo group) patients were included. The pain intensity was significantly lower in the LP group at each time point (66%-68% pain reduction, P < 0.001, interaction of time × treatment P = 0.69). In addition, the total dose of rescue opioids used for 48 h was significantly lower in the L group (27.2% reduction, P = 0.008). No significant differences were found in other outcome variables between the 2 groups. IMPLICATIONS: The application of a 5% LP on each side of the sternotomy site can reduce PSP and additional opioid use without significant adverse effects in patients undergoing sternotomy. Thus, it can be considered as a standard and routine modality along with other analgesic medications for the management of PSP. Clinical Trial Registry in South Korea identifier: KCT0000476.

Dexmedetomidine-remifentanil vs propofol-remifentanil for monitored anesthesia care during hysteroscopy: Randomized, single-blind, controlled trial.

BACKGROUND: Although dexmedetomidine has been used as either the anesthetic agent for light sedation or as an adjunct to other sedatives, no study has investigated the usefulness of dexmedetomidine as the main sedative agent for invasive and painful procedures. The purpose of this study was to compare the safety of dexmedetomidine-remifentanil and propofol-remifentanil during monitored anesthesia care (MAC) for hysteroscopy. METHODS: Female patients undergoing hysteroscopy were randomly assigned to either the dexmedetomidine (group D) or the propofol group (group P). The study drug (0.6 ml/kg; dexmedetomidine 2 µg/ml or propofol 4 mg/ml) was loaded for 10 minutes followed by 0.1 to 0.5 ml/kg/hour to maintain a bispectral index of 60 to 80 during the procedure. In both groups, remifentanil was infused using a target-controlled-infusion system with a target concentration of 2 ng/ml and titrated during the procedure. The incidence rates of intraoperative respiratory depression in both groups were compared. Postoperative pain and patients satisfaction were also compared. RESULTS: A total of 69 female patients were included in this study. Dexmedetomidine significantly decrease the incidence of respiratory depression compared with propofol (15/34 [44.1%] vs 5/35 [14.3%], P = .006, group P and D, respectively). Postoperative pain and patients satisfaction score did not differ between the groups. CONCLUSION: The combination of dexmedetomidine-remifentanil can reduce the incidence of respiratory depression without increasing hemodynamic complications compared with propofol-remifentanil for MAC during hysteroscopy.

Deep neuromuscular block improves angiographic image quality during endovascular coiling of unruptured cerebral aneurysm: a randomized clinical trial.

BACKGROUND: Neuromuscular block (NMB) used during general anesthesia induces transient skeletal muscle paralysis, but patient movements during endovascular coiling still occur to some degree. Compared with moderate NMB, deep NMB may further improve the intervention condition during endovascular coiling for unruptured cerebral aneurysms; however, little research has focused on the angiographic image quality. METHODS: This prospective, randomized, double-blind clinical trial included 58 patients treated for unruptured cerebral aneurysms with endovascular coiling under general anesthesia. Patients were randomly allocated to either the deep NMB group (post-tetanic count 1 or 2) or the moderate NMB group (train-of-four 1 or 2). The primary outcome was the proportion of patients with a satisfactory intervention condition assessed by surgeons after the procedure using a 5-point intervention condition rating scale (ICRS) from 1 (unable to obtain image) to 5 (optimal); ICRS 5 was defined as satisfactory. RESULTS: There were significantly more cases of satisfactory intervention condition in the deep NMB group than in the moderate NMB group (82.1% vs 51.7%, p=0.015). The frequency of each ICRS score was significantly different between the groups (ICRS 5/4/3/2/1: 23/5/0/0/0 vs 15/9/2/3/0, p=0.035). The incidence of major patient movement requiring rescue muscle relaxant was 10.3% in the moderate NMB group and 0% in the deep NMB group (p=0.237). The drugs used to maintain hemodynamic stability were not significantly different between the two groups. CONCLUSIONS: Deep NMB improves the intervention condition during endovascular coiling by improving the image quality.

Comparison of conventional and fibreoptic-guided advance of left-sided double-lumen tube during endobronchial intubation: A randomised controlled trial.

BACKGROUND: Postoperative sore throat and airway injuries are relatively common after double-lumen tube (DLT) intubation. OBJECTIVE: The current study aimed to evaluate the effects of fibreoptic-guided advance of DLT on postoperative sore throat and airway injuries associated with intubation. DESIGN: A randomised controlled study. SETTING: Tertiary hospital, Seongnam, Korea, from January 2018 to January 2019. PATIENTS: One hundred twenty three patients undergoing one-lung ventilation with a left-side DLT were randomised into two groups: 62 in the conventional group and 61 in the fibreoptic-guided group. INTERVENTION: After entering the glottis, the DLT was rotated left 90° and advanced blindly into the left main bronchus in the conventional group. In the fibreoptic-guided group, DLT was advanced into the main bronchus under the guide of fibreoptic bronchoscope, which had been passed through the bronchial lumen and inserted into the left main bronchus. MAIN OUTCOME MEASURES: The primary outcome was postoperative sore throat at 24 h after operation. The airway injuries were also examined using a bronchoscope during extubation. RESULTS: At postoperative 24 h, the fibreoptic-guided group showed lower pain score (P = 0.001) and lower incidence (risk ratio [95% CI]: 0.2 [0.1 to 0.5], P < 0.001) of sore throat, compared with the conventional group. Moreover, tracheal injury was more severe in the conventional group than in the fibreoptic group (P = 0.003). Vocal cord injuries also occurred less frequently in the fibreoptic-guided group (risk ratio [95% CI]: 0.4 [0.2 to 1.0], P = 0.036). CONCLUSION: The fibreoptic-guided advancement seems to reduce irritation to the airway, leading less postoperative complications. TRIAL REGISTRATION: ClinicalTrials.gov, registration number: NCT03368599.

Magnesium Sulfate Treatment During Total Knee Arthroplasty Decreases Postoperative Urinary Retention: A Retrospective Propensity Score-Matched Analysis.

Postoperative urinary retention (POUR) is a common complication after total knee arthroplasty. Currently, there are no clinical data regarding the effects of magnesium sulfate on POUR. Here, we investigated the effects of intraoperative magnesium sulfate infusion in patients with POUR following total knee arthroplasty. We reviewed the medical records of patients who underwent elective unilateral total knee arthroplasty under spinal anesthesia between June 2016 and May 2018. The patients were grouped based on whether they were treated with magnesium (magnesium group) or not (control group). We investigated the incidence of POUR and the postoperative analgesic requirement. Totally, 483 patients were included in the analysis. After propensity score matching with the control group, the magnesium group showed a lower incidence of POUR (odds ratio, 0.49; 95% CI, 0.29-0.83; p = 0.011) and lesser opioid consumption (p = 0.049) than the control group. Multivariate logistic regression analysis revealed that intraoperative continuous infusion of magnesium (p = 0.008) and age (p = 0.001) were significantly related to the incidence of POUR. This retrospective observational study demonstrated that administration of magnesium sulfate was associated with a lower incidence of POUR following total knee arthroplasty.

Complications in internal jugular vs subclavian ultrasound-guided central venous catheterization: a comparative randomized trial.

PURPOSE: The use of real-time ultrasound (US) has been shown to reduce complications of central venous (CV) catheterization. However, complication rates have not been compared according to insertion points for CV catheterization using US. Accordingly, this study aimed to compare the complication rates of internal jugular vein (IJV) with those of subclavian vein (SCV) catheterization. METHODS: Three tertiary academic hospitals in South Korea participated in this multicenter, randomized study. A total of 1484 patients were preoperatively randomized into two groups. The IJV group (n = 742) was cannulated via the right IJV, and the SCV group (n = 742) was cannulated via the right SCV under US guidance. The primary outcome measure was total complication rate. Secondary outcomes included access time for the first attempt, number of attempts, and catheter position. RESULTS: The total complication rate did not demonstrate a significant difference between the IJV (0.1%) and SCV (0.7%) groups (P = 0.248). In the IJV group, arterial puncture occurred in 0.1% of patients; in the SCV group, arterial puncture occurred in 0.6% and pneumothorax in 0.1%. The success rate on the first attempt was significantly higher in the IJV group (98.4%) than in the SCV group (95.9%) (P = 0.004). The access time for the first attempt (P < 0.001) and the median number of attempts (P = 0.006) were significantly lower in the IJV group than in the SCV group. More catheter misplacements were observed in the SCV group (5.9%) than in the IJV group (0.4%) (P < 0.001). CONCLUSION: Results demonstrated that the complication rates of IJV and SCV catheterizations using US are very low, showing no superiority of the SCV approach compared to the IJV.

Comparison of Simple Stylet versus Lighted Stylet for Intubating the Trachea with a Direct Laryngoscope: A Randomized Clinical Trial.

This study investigated the effectiveness of a lighted stylet during tracheal intubation with direct laryngoscopy. The study randomly assigned 284 patients undergoing general anesthesia to either the simple stylet (Group S) or lighted stylet (Group L) groups. In both groups, stylet-assisted intubation was performed with direct laryngoscopy. In group S, a simple stylet was used and removed when the tip of the endotracheal tube was thought to have passed the larynx. In Group L, a lighted stylet was used and removed after confirming transillumination of the suprasternal notch. The success rate at the first attempt, total intubation time, incidence of mucosal bleeding, and severity of postoperative sore throat were compared. Compared to a simple stylet, the lighted stylet significantly increased the success rate of tracheal intubation at the first attempt (128 (90%) vs. 140 (99%), p = 0.003, Groups S and L, respectively). The incidence of mucosal bleeding was significantly higher in Group S (35 (25%) vs. 19 (13%), p = 0.011, Groups S and L, respectively). The total intubation time and degree of postoperative sore throat were not significantly different between the two groups. A lighted stylet increased the success rate of tracheal intubation during stylet-assisted tracheal intubation with direct laryngoscopy.

Midazolam Premedication Facilitates Mask Ventilation During Induction of General Anesthesia: A Randomized Clinical Trial.

BACKGROUND: During induction of general anesthesia, proper mask ventilation is crucial for supplying sufficient oxygen to unconscious patients. Midazolam has a relaxing effect on airway muscles. We hypothesized that sedative premedication with midazolam would facilitate mask ventilation during anesthetic induction. METHODS: Patients undergoing elective surgery under general anesthesia were randomized into 2 groups. The midazolam group received midazolam premedication at the reception area, 3 minutes before transfer to the operating room. Patients in the control group were treated with normal saline as a placebo. The primary outcome was difficulty of mask ventilation during induction, as evaluated using the Warters scales. RESULTS: A total of 97 patients completed the analysis: 49 in the control group and 48 in the midazolam group. The patients in the midazolam group showed a significantly lower mask ventilation difficulty score on the Warters scale than that of the control group (mean [standard deviation], 0.92 [1.13] vs 0.19 [0.57]; estimated difference [95% confidence interval], 0.73 [0.37-1.09]; P < .001). The incidence of difficult mask ventilation (≥2 Warters scale) was significantly lower in the midazolam group than in the control group (risk ratio [95% confidence interval], 0.15 [0.03-0.72]; P = .015). CONCLUSIONS: This randomized clinical trial demonstrated that midazolam premedication enhanced mask ventilation during induction of general anesthesia.

The attenuation of neurological injury from the use of simvastatin after spinal cord ischemia-reperfusion injury in rats.

BACKGROUND: Spinal cord ischemic injury remains a serious complication of open surgical and endovascular aortic procedures. Simvastatin has been reported to be associated with neuroprotective effect after spinal cord ischemia-reperfusion (IR) injury. The aim of this study was to determine the therapeutic efficacy of starting simvastatin after spinal cord IR injury in a rat model. METHODS: In adult Sprague-Dawley rats, spinal cord ischemia was induced using a balloon-tipped catheter placed in the descending thoracic aorta. The animals were then randomly divided into 4 groups: group A (control); group B (0.5 mg/kg simvastatin); group C (1 mg/kg simvastatin); and group D (10 mg/kg simvastatin). Simvastatin was administered orally upon reperfusion for 5 days. Neurological function of the hind limbs was evaluated for 7 days after reperfusion and recorded using a motor deficit score (MDS) (0: normal, 5: complete paraplegia). The number of normal motor neurons within the anterior horns of the spinal cord was counted after final MDS evaluation. Then, the spinal cord was harvested for histopathological examination. RESULTS: Group D showed a significantly lower MDS than the other groups at post-reperfusion day 1 and this trend was sustained throughout the study period. Additionally, a greater number of normal motor neurons was observed in group D than in other groups (group D 21.2 [3.2] vs. group A: 15.8 [4.2]; group B 15.4 [3.4]; and group C 15.5 [3.7]; P = 0.002). CONCLUSIONS: The results of the current study suggest that 10 mg/kg can significantly improve neurologic outcome by attenuating neurologic injury and restoring normal motor neurons after spinal cord IR injury.

Effects of short-term exposure to sevoflurane on the survival, proliferation, apoptosis, and differentiation of neural precursor cells derived from human embryonic stem cells.

PURPOSE: Data from animal experiments suggest that exposure to general anesthetics in early life inhibits neurogenesis and causes long-term memory deficit. Considering short operating times and the popularity of sevoflurane in pediatric anesthesia, it is important to verify the effects of short-period exposure to sevoflurane on the developing brain. METHODS: We measured the effects of short-term exposure (2 h) to 3%, 6%, or 8% sevoflurane, the most commonly used anesthetic, on neural precursor cells derived from human embryonic stem cells, SNUhES32. Cell survival, proliferation, apoptosis, and differentiation on days 1, 3, 5, and 7 post treatment were analyzed. RESULTS: Treatment with 6% sevoflurane increased cell viability (P = 0.046) and decreased apoptosis (P = 0.014) on day 5, but the effect did not persist on day 7. Survival and apoptosis were not affected by 3% and 8% sevoflurane; there was no effect of proliferation at any of the tested concentrations. The differentiation of cells exposed to 6% or 8% sevoflurane decreased on day 1 (P = 0.033 and P = 0.036 for 6% and 8% sevoflurane, respectively) but was again normalized on days 3-7. CONCLUSION: Clinically relevant treatment with sevoflurane for 2 h induces no significant changes in the survival, proliferation, apoptosis, and differentiation of human neural precursor cells, although supraclinical doses of sevoflurane do alter human neurogenesis transiently.

Reproducible Motor Deficit Following Aortic Occlusion in a Rat Model Of Spinal Cord Ischemia.

Spinal cord ischemia is a fatal complication following thoracoabdominal aortic aneurysm surgery. Researchers can investigate the strategies for preventing and treating this complication using experimental models of spinal cord ischemia. The model described here demonstrates varying degrees of paraplegia that relate to the length of occlusion following thoracic aortic occlusion in a rat spinal cord ischemia model. A 2-Fr. balloon-tipped catheter was advanced through the femoral artery into the descending thoracic aorta until the catheter tip was placed at the left subclavian artery in anesthetized male Sprague-Dawley rats. Spinal cord ischemia was induced by inflating the catheter balloon. After a set period of occlusion (9, 10, or 11 min), the balloon was deflated. Neurologic assessment was performed using the motor deficit index at 24 h after surgery, and the spinal cord was harvested for histopathological examination. Rats that underwent 9 min of aortic occlusion showed mild and reversible motor impairment in the hind limb. Rats subjected to 10 min of aortic occlusion presented with moderate but reversible motor impairment. Rats subjected to 11 min of aortic occlusion displayed complete and persistent paralysis. The motor neurons in the spinal cord sections were more preserved in rats subjected to shorter duration of aortic occlusion. Researchers can achieve a reproducible hind limb motor deficit following thoracic aortic occlusion using this spinal cord ischemia model.

Previsional space during direct laryngoscopy: Implication in the difficult laryngoscopy.

The laryngoscope should displace oral soft tissues forward out of the operator's vision. Therefore, the space in front of the view may be critical for determining the laryngoscopic view. The aim was to investigate the difference in the previsional space during difficult versus easy laryngoscopy (EL).Under general anesthesia, digital photographs of the lateral view of the head and neck were taken in the horizontal sniffing position, after head extension, and during laryngoscopy with a defined force (50 N). Three points (thyroid notch (T), maxillary incisor (I), and mandibular mentum (M)) were marked on the photograph. The previsional space was defined as the TIM triangle. We compared these areas and other variables of the TIM triangle between male patients with difficult laryngoscopy (DL: Cormack-Lehane III-IV, n = 12) versus those of age- and body mass index-matched male patients with EL (Cormack-Lehane I-II, n = 12).When the head was extended, the areas TIM triangle in DL were significantly smaller than in EL. During laryngoscopy, all values of the TIM triangle in DL, including the TIM area (16.4 ±â€Š3.7 vs 22.6 ±â€Š2.8 cm, P < .01), were significantly smaller than the values in EL.The previsional space was smaller in patients with DL than in those with EL. The TIM triangle could suggest new way to explain the mechanism underlying DL.

Simvastatin protects ischemic spinal cord injury from cell death and cytotoxicity through decreasing oxidative stress: in vitro primary cultured rat spinal cord model under oxygen and glucose deprivation-reoxygenation conditions.

BACKGROUND: Ischemia and the following reperfusion damage are critical mechanisms of spinal cord injury. Statins have been reported to decrease ischemia-reperfusion injury in many organs including the spinal cord. Anti-oxidative effect is one of the main protective mechanisms of statin against neuronal death and cytotoxicity. We hypothesized that statins' anti-oxidative property would yield neuroprotective effects on spinal cord ischemia-reperfusion injury METHODS: Primary cultured spinal cord motor neurons were isolated from Sprague-Dawley rat fetuses. Ischemia-reperfusion injury model was induced by 60 min of oxygen and glucose deprivation (OGD) and 24 h of reoxygenation. Healthy and OGD cells were treated with simvastatin at concentrations of 0.1, 1, and 10 µM for 24 h. Cell viability was assessed using water-soluble tetrazolium salt (WST)-8, cytotoxicity with LDH, and production of free radicals with DCFDA (2',7'-dichlorofluorescein diacetate). RESULTS: OGD reduced neuronal viability compared to normoxic control by 35.3%; however, 0.1-10 µM of simvastatin treatment following OGD improved cell survival. OGD increased LDH release up to 214%; however, simvastatin treatment attenuated its cytotoxicity at concentrations of 0.1-10 µM (p < 0.001 and p = 0.001). Simvastatin also reduced deteriorated morphological changes of motor neurons following OGD. Oxidative stress was reduced by simvastatin (0.1-10 µM) compared to untreated cells exposed to OGD (p < 0.001). CONCLUSIONS: Simvastatin effectively reduced spinal cord neuronal death and cytotoxicity against ischemia-reperfusion injury, probably via modification of oxidative stress.

Isoflurane decreases proliferation and differentiation, but none of the effects persist in human embryonic stem cell-derived neural progenitor cells.

PURPOSE: Volatile anesthetics are a potential risk for cognitive impairment in the developing brain. Isoflurane causes cell death, reduces neurogenesis, and changes neuronal differentiation. In this study, the effects of a single isoflurane exposure on the developing human brain were evaluated using human embryonic stem cell (hESC)-derived neural progenitor cells (NPCs). METHODS: Multipotent NPCs were derived from hESCs and randomly exposed to either 5 vol% isoflurane (4 h) or no isoflurane (control group). The cells were fixed after 1, 3, 5, and 7 days to evaluate differentiation using the ratio of ß-III tubulin to nestin. Neuronal cell survival and proliferation were assessed using the WST-1 and bromodeoxyuridine (BrdU) cell proliferation assays, respectively. To evaluate the mechanism of isoflurane neurotoxicity, we added TAT-Pep5, a p75 neurotrophic receptor (p75NTR) inhibitor, to each of the groups. RESULTS: Isoflurane had minimal or no effect on the cell survival of NPCs in vitro. Proliferation, assessed on the basis of BrdU incorporation, was inhibited in the isoflurane group on days 3 (p = 0.033) and 5 (p = 0.001). The ratios of ß-III tubulin to nestin in the isoflurane group on days 1 and 3 were significantly lower (p = 0.004 and p = 0.029, respectively) than those in the control group. Anti-proliferative and differentiation-reducing effect did not persist. TAT-Pep5 pretreatment significantly blocked the isoflurane-mediated decrease in the ß-III tubulin to nestin ratio (p = 0.012) on day 1. CONCLUSION: Exposing NPCs to isoflurane hampered proliferation and differentiation but not neuronal survival. Isoflurane may be a powerful neuronal modulator during the early developmental period, partly mediated by activation of p75NTR.