Cervical Spine Motion During Tracheal Intubation Using an Optiscope Versus the McGrath Videolaryngoscope in Patients With Simulated Cervical Immobilization: A Prospective Randomized Crossover Study.

BACKGROUND: In patients with an unstable cervical spine, maintenance of cervical immobilization during tracheal intubation is important. In McGrath videolaryngoscopic intubation, lifting of the blade to raise the epiglottis is needed to visualize the glottis, but in patients with an unstable cervical spine, this can cause cervical spine movement. By contrast, the Optiscope, a rigid video-stylet, does not require raising of the epiglottis during tracheal intubation. We therefore hypothesized that the Optiscope would produce less cervical spine movement than the McGrath videolaryngoscope during tracheal intubation. The aim of this study was to compare the Optiscope with the McGrath videolaryngoscope with respect to cervical spine motion during intubation in patients with simulated cervical immobilization. METHODS: The primary outcome of the study was the extent of cervical spine motion at the occiput-C1, C1-C2, and C2-C5 segments. In this randomized crossover study, the cervical spine angle was measured before and during tracheal intubation using either the Optiscope or the McGrath videolaryngoscope in 21 patients with simulated cervical immobilization. Cervical spine motion was defined as the change in angle at each cervical segment during tracheal intubation. RESULTS: There was significantly less cervical spine motion at the occiput-C1 segment using the Optiscope rather than the McGrath videolaryngoscope (mean [98.33% CI]: 4.7° [2.4-7.0] vs 10.4° [8.1-12.7]; mean difference [98.33% CI]: -5.7° [-7.5 to -3.9]). There were also fewer cervical spinal motions at the C1-C2 and C2-C5 segments using the Optiscope (mean difference versus the McGrath videolaryngoscope [98.33% CI]: -2.4° [-3.7 to -1.2]) and -3.7° [-5.9 to -1.4], respectively). CONCLUSIONS: The Optiscope produces less cervical spine motion than the McGrath videolaryngoscope during tracheal intubation of patients with simulated cervical immobilization.

Effects of a Lidocaine-Loaded Poloxamer/Alginate/CaCl2 Mixture on Postoperative Pain and Adhesion in a Rat Model of Incisional Pain.

BACKGROUND: Pain and adhesion are problematic issues after surgery. Lidocaine has analgesics and anti-inflammatory properties, and poloxamer/alginate/CaCl2 (PACM) is a known antiadhesive agent. We hypothesized that the novel combination of lidocaine as chemical barrier and PACM as physical barrier would be beneficial for both postoperative pain and adhesion. The purpose of this study was to investigate the effects of lidocaine-loaded PACM in a rat model of incisional pain. Primary outcome was to evaluate between-group differences for the mechanical withdrawal threshold (MWT) measured by von Frey filament in various concentrations of lidocaine-loaded PACM applied, PACM applied, and sham-operated groups. METHODS: Male Sprague-Dawley rats were used for the postoperative pain model. After plantar incision and adhesion formation, 0.5%, 1%, 2%, and 4% lidocaine-loaded PACM, PACM only, nothing, and 4% lidocaine only were applied at the incision site in groups PL0.5, PL1, PL2, PL4, P, S, and L4, respectively. MWT using a von Frey filament and serum levels of tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, and high-sensitivity C-reactive protein were measured. Rats were euthanized 2 weeks after surgery, and inflammation and fibrosis were assessed with microscopy. Data were analyzed using the Kruskal-Wallis test, multivariate analysis of variance, and linear mixed-effect model. To compare MWT at each time point, analysis of variance with Bonferroni correction was used. RESULTS: Multivariate analysis of variance showed that 4% lidocaine-loaded PACM significantly raised the MWT up to 6 and 8 hours after surgery compared with lidocaine-unloaded groups S and P, respectively; 2% lidocaine-loaded PACM significantly increased the MWT at 4 hours after surgery compared with groups S and C. Linear mixed-effect model showed that the MWT (estimated difference in means [95% confidence interval]) was significantly increased in groups PL2 and PL4 (6.58 [2.52-10.63], P = .002; 11.46 [7.40-15.51], P < .001, respectively) compared with group P. Inflammation and fibrosis seen on microscopic evaluation were significantly decreased in groups PL2 and PL4 compared with group S. Four percent of lidocaine only showed a significant reduction in inflammation. Serum levels of tumor necrosis factor-α, IL-1ß, IL-6, and high-sensitivity C-reactive protein were decreased in lidocaine-loaded groups compared with group S or P at 1, 2, and 48 hours, and 2 weeks after surgery, respectively. CONCLUSIONS: Lidocaine-loaded PACM reduced postoperative pain, and lidocaine strengthened the antiadhesive effect of PACM.

Publication Delay of Korean Medical Journals.

Publication lag is a determinant to journal efficiency that was not yet studied concerning Korean medical journals. To measure publication lag, we investigated the publication timestamps of 4,762 articles published by 10 Korean medical journals indexed in Scopus database, randomly selected from the KoreaMed Synapse since 2013. The total publication lag was 246.5 (Q1, Q3; 178.0, 347.0) days. The overall acceptance lag was 102.0 (65.0, 149.0) days. The overall lead lag was 123.0 (63.0, 236.0) days. The year of publication did not significantly affect the acceptance lag (P = 0.640), supposedly shortening it by about 1.4 (97.5% confidence interval [CI], ?5.2 to 8.0) days/year, while the date affected the lead lag (P = 0.028), shortening it by about 12.9 (1.3 to 24.5) days/year. The Korean medical journals have reduced the total publication delay entirely by means of reducing the lead lag, not by reducing the acceptance lag.

Effects of sevoflurane increments on left ventricular systolic long-axis performance during sevoflurane-remifentanil anesthesia for cardiovascular surgery.

BACKGROUND: The direct impact of sevoflurane on intraoperative left ventricular (LV) systolic performance during cardiac surgery has not been fully elucidated. Peak systolic tissue Doppler velocities of the lateral mitral annulus (S') have been used to evaluate LV systolic long-axis performance. We hypothesized that incremental sevoflurane concentration (1.0-3.0 inspired-vol%) would dose-dependently reduce S' in patients undergoing cardiac surgery due to mitral or aortic insufficiency. METHODS: In 20 patients undergoing cardiac surgery in sevoflurane-remifentanil anesthesia, we analyzed intraoperative S' values which were determined after 10 min exposure to sevoflurane at 1.0, 2.0, and 3.0 inspired-vol% (T1, T2, and T3, respectively) with a fixed remifentanil dose (1.0 µg/kg/min) using transesophageal echocardiography. RESULTS: Linear mixed-effect modeling demonstrated dose-dependent declines in S' according to the end-tidal sevoflurane concentration increments (C(ET)-sevoflurane, p < 0.001): the mean value of S' reduction for each 1.0 vol%-increment of C(ET)-sevoflurane was 1.7 cm/s (95 % confidence interval 1.4-2.1 cm/s). Medians of S' at T1, T2, and T3 (9.6, 8.9, and 7.5 cm/s, respectively) also exhibited significant declines (by 6.6, 15.6, and 21.2 % for T1 vs. T2, T2 vs. T3, and T1 vs. T3, p < 0.001, =0.002, and <0.001 in Friedman pairwise comparisons, respectively). CONCLUSIONS: Administering sevoflurane as a part of a sevoflurane-remifentanil anesthesia regimen appears to dose-dependently reduce S', indicating LV systolic performance, in patients undergoing cardiac surgery. Further studies may be required to evaluate the clinical implications of these findings.

A comparison of posterior and medial cord stimulation for neurostimulation-guided vertical infraclavicular block: a randomized noninferiority clinical trial.

BACKGROUND: We investigated whether medial cord stimulation is inferior to posterior cord stimulation for vertical infraclavicular block with respect to block success. METHODS: Ninety-six patients scheduled for upper limb surgery were randomly elicited a medial or posterior cord response for infraclavicular block using 40 mL of 0.5% ropivacaine. We assessed block success (complete sensory block of the 5 nerves in the forearm at 50 minutes) as the primary end point and block procedure characteristics and adverse events as secondary end points. RESULTS: The block success rates did not differ significantly between medial and posterior cord stimulation (95.7% [44/46] vs 91.7% [44/48], 95% CI of difference, -7.4% to 15.6%), while the secondary end points were comparable in both groups. CONCLUSIONS: Needle manipulation to elicit medial cord response is noninferior to posterior cord response of block success during neurostimulation-guided vertical infraclavicular block.

A randomized comparison of ropivacaine 0.1% and 0.2% for continuous interscalene block after shoulder surgery.

BACKGROUND: The optimal concentration of ropivacaine for continuous interscalene block after shoulder surgery is currently unknown. METHODS: Fifty-six patients received a perineural infusion of either ropivacaine 0.1% or 0.2% for 48 hours after shoulder surgery. We assessed pain scores as primary end points and supplemental analgesia, ropivacaine consumption, motor block, side effects, and patient satisfaction as secondary end points. RESULTS: Pain scores were not statistically different during the infusion periods; however, supplemental analgesia consumption was higher in the group receiving ropivacaine 0.1% during the first 24 hours (64% vs 28%, P = 0.022). Other secondary end points were statistically inconclusive. CONCLUSIONS: These results suggest that ropivacaine 0.2% provides more effective analgesia than ropivacaine 0.1% during the first 24 hours for continuous interscalene block after shoulder surgery.

Structure-oriented versus process-oriented approach to enhance efficiency for emergency room operations: what lessons can we learn?

The efficiency and quality of a healthcare system can be defined as interactions among the system structure, processes, and outcome. This article examines the effect of structural adjustment (change in floor plan or layout) and process improvement (critical pathway implementation) on performance of emergency room (ER) operations for acute cerebral infarction patients. Two large teaching hospitals participated in this study: Korea University (KU) Guro Hospital and KU Anam Hospital. The administration of Guro adopted a structure-oriented approach in improving its ER operations while the administration of Anam employed a process-oriented approach, facilitating critical pathways and protocols. To calibrate improvements, the data for time interval, length of stay, and hospital charges were collected, before and after the planned changes were implemented at each hospital. In particular, time interval is the most essential measure for handling acute stroke patients because patients' survival and recovery are affected by the promptness of diagnosis and treatment. Statistical analyses indicated that both redesign of layout at Guro and implementation of critical pathways at Anam had a positive influence on most of the performance measures. However, reduction in time interval was not consistent at Guro, demonstrating delays in processing time for a few processes. The adoption of critical pathways at Anam appeared more effective in reducing time intervals than the structural rearrangement at Guro, mainly as a result of the extensive employee training required for a critical pathway implementation. Thus, hospital managers should combine structure-oriented and process-oriented strategies to maximize effectiveness of improvement efforts.

Effects of etomidate use in ICU patients on ventilator therapy: a study of 12,526 patients in an open database from a single center.

BACKGROUND: There is a debate regarding the safety of etomidate. We evaluated the effects of etomidate on mortality in a large cohort of critical care patients. METHODS: This retrospective matched-cohort study was performed using the Medical Information Mart for Intensive Care version 3 (MIMIC-III) database. Among 12,526 adult patients who were prescribed etomidate or propofol on the first day of mechanical ventilation, 625 patients administered etomidate were statistically matched with 6,250 patients administered propofol. The primary outcome measures were all-cause in-hospital mortality, 48-hour survival, cardiovascular morbidity, and infectious morbidity. Logistic regression analysis with stepwise selection of variables was performed to examine the dose-mortality relationship of etomidate. RESULTS: All-cause in-hospital mortality was 1.84 times higher in the etomidate cohort (OR, 1.84; 98.75% CI, 1.42, 2.37). Compared to the propofol cohort, the etomidate cohort showed 57% lower odds of 48-hour survival (0.43 [0.27, 0.73]), no difference in odds of cardiovascular morbidity (0.86 [0.66, 1.12]), and 1.77 times higher odds of infectious morbidity (1.77 [1.35, 2.31]). Additionally, the odds of mortality increased by 1.36 times per 0.1 mg/kg of etomidate (1.36 [95% CI: 1.23, 1.49]). CONCLUSIONS: Etomidate is a poor choice as a hypnotic drug on the first day of mechanical ventilation, as it is associated with a dose-dependent increase in all-cause mortality, and does not improve survival for the first 48 h.

Positional blood pressure change and the risk of hypotension during spinal anesthesia for cesarean delivery: an observational study.

BACKGROUND: We investigated whether preoperative positional arterial blood pressure change predicted hypotension and ephedrine requirement during spinal anesthesia for cesarean delivery. METHODS: Arterial blood pressure was measured in 66 women undergoing cesarean delivery in the supine and the right lateral positions. Positional blood pressure change was defined as the difference between mean blood pressure in the right lateral and supine positions. Hypotension (<80% baseline) was recorded, and severe hypotension (<70% baseline) was treated with ephedrine. RESULTS: The mean (range) positional blood pressure change was 11 (3-29) mm Hg, and the incidence of hypotension was 41%. Positional blood pressure change and heart rate correlated with hypotension (P < 0.001 for both) and ephedrine requirement (P = 0.004). Positional blood pressure change in those who developed hypotension was higher than for those without hypotension (mean (SD), 17 (6) vs. 7 (2) mm Hg, P < 0.001). CONCLUSIONS: A preoperative increase in blood pressure after position change may be a good variable to predict hypotension during spinal anesthesia for cesarean delivery.

Elixhauser comorbidity measures-based risk factors associated with 30-day mortality in elderly population after femur fracture surgery: a propensity scorematched retrospective case-control study.

BACKGROUND: As the average life expectancy increases, anesthesiologists confront unique challenges in the perioperative care of elderly patients who have significant comorbidities. In this study, we evaluated Elixhauser comorbidity measures-based risk factors associated with 30day mortality in patients aged 66 years and older who underwent femur fracture surgery. METHODS: We used the Medical Information Mart for Intensive Care III which contains the medical records of patients admitted to the intensive care unit (ICU) at Beth Israel Deaconess Medical Center in the United States between 2001 and 2012 to identify patients admitted to the ICU after femur fracture surgery (n=209). Patients who died within 30 days of admission (case group, n=49) were propensity score-matched to patients who did not (control group, n=98). The variables for matching were age, sex, race, anemia (hemoglobin ≤10 g/dl), and malignancy. We attempted to explain mortality via nine independent factors: hypertension, uncomplicated diabetes, complicated diabetes, congestive heart failure (CHF), cardiac arrhythmias, chronic pulmonary disease, renal failure, neurological disorders other than paralysis, and peripheral vascular disease. RESULTS: Logistic regression identified three significant risk factors: CHF, arrhythmias, and neurological disorders other than paralysis. The odds ratio (OR) for the 30-day mortality of CHF was 4.99 (95% confidence interval [CI], 2.18 to 12.06). The equivalent ORs for cardiac arrhythmias and neurological disorders other than paralysis were 2.61 (95% CI, 1.14 to 6.21) and 2.40 (95% CI, 0.95 to 6.48), respectively. CONCLUSIONS: Identifying patients with these risk factors (CHF, arrhythmias, and neurological disorders other than paralysis) will assist clinicians with perioperative planning and provide caregivers with valuable information for decision-making.

Hypocapnia attenuates, and nitrous oxide disturbs the cerebral oximetric response to the rapid introduction of desflurane.

The aim of this study was to develop a nonlinear mixed-effects model for the increase in cerebral oximetry (rSO(2)) during the rapid introduction of desflurane, and to determine the effect of hypocapnia and N(2)O on the model. Twelve American Society of Anesthesiologist physical status class 1 and 2 subjects were allocated randomly into an Air and N(2)O group. After inducing anesthesia, desflurane was then increased abruptly from 4.0 to 12.0%. The PET(CO2), PET(DESF) and rSO(2) were recorded at 12 predetermined periods for the following 10 min. The maximum increase in rSO(2) reached +24-25% during normocapnia. The increase in rSO(2) could be fitted to a four parameter logistic equation as a function of the logarithm of PET(DESF). Hypocapnia reduced the maximum response of rSO(2), shifted the EC(50) to the right, and increased the slope in the Air group. N(2)O shifted the EC(50) to the right, and reduced the slope leaving the maximum rSO(2) unchanged. The N(2)O-effects disappeared during hypocapnia. The cerebrovascular reactivity of rSO(2) to CO(2) is still preserved during the rapid introduction of desflurane. N(2)O slows the response of rSO(2). Hypocapnia overwhelms all the effects of N(2)O.

Initial Seizure Threshold in Brief-Pulse Bilateral Electroconvulsive Therapy in Patients with Schizophrenia or Schizoaffective Disorder.

OBJECTIVE: The present study aimed to report the initial seizure threshold (IST) of a brief-pulse bilateral electroconvulsive therapy (BP-BL ECT) in Korean patients with schizophrenia/schizoaffective disorder and to identify IST predictors. METHODS: Among 67 patients who received ECT and diagnosed with schizophrenia/schizoaffective disorder based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, we included 56 patients who received 1-millisecond BP-BL ECT after anesthesia with sodium thiopental between March 2012 and June 2018. Demographic and clinical information was gathered from electronic medical records, and a multiple regression analysis was conducted to identify predictors of the IST. RESULTS: The mean age of the patients was 36.9±12.0 years and 30 (53.6%) patients were male. The mean and median IST were 105.9±54.5 and 96 millicoulombs (mC), respectively. The IST was predicted by age, gender, and dose (mg/kg) of sodium thiopental. Other physical and clinical variables were not associated with the IST. CONCLUSION: The present study demonstrated that the IST of 1-ms BP-BL ECT following sodium thiopental anesthesia in Korean patients was comparable to those reported in previous literature. The IST was associated with age, gender, and dose of sodium thiopental.

Characteristics of the similarity index in a Korean medical journal.

BACKGROUND: Journal editors have exercised their control over submitted papers having a high similarity index. Despite widespread suspicion of possible plagiarism on a high similarity index, our study focused on the real effect of the similarity index on the value of a scientific paper. METHODS: This research examined the percent values of the similarity index from 978 submitted (420 published) papers in the Korean Journal of Anesthesiology since 2012. Thus, this study aimed to identify the correlation between the similarity index and the value of a paper. The value of a paper was evaluated in two distinct phases (during a peer-review process vs. after publication), and the value of a published paper was evaluated in two aspects (academic citation vs. social media appearance). RESULTS: Yearly mean values of the similarity index ranged from 16% to 19%. There were 254 papers cited at least once and 179 papers appearing at least once in social media. The similarity index affected the acceptance/rejection of a paper in various ways; although the influence was not linear and the cutoff measures were distinctive among the types of papers, both extremes were related to a high rate of rejection. After publication, the similarity index had no effect on academic citation or social media appearance according to the paper. CONCLUSIONS: The finding suggested that the similarity index no longer had an influence on academic citation or social media appearance according to the paper after publication, while the similarity index affected the acceptance/rejection of a submitted paper. Proofreading and intervention for finalizing the draft by the editors might play a role in achieving uniform quality of the publication.

Three-dimensional transesophageal echocardiography for determination of the mitral valve area after mitral valve repair surgery for mitral stenosis.

BACKGROUND: Pressure half-time (PHT) method is usually unreliable for accurate determination of mitral valve area (MVA) immediately after surgical intervention of mitral stenosis (MS). The planimetry method using three-dimensional (3D) transesophageal echocardiography (3D-planimetery method) could enhance accurate determination of the intraoperative MVA. Authors investigated the efficacy of 3D-planimetry method in determining MVA immediately after mitral valve repair procedure (MVRep) for severe mitral stenosis (MS). METHODS: In severe MS patients undergoing elective MVRep (N.=41), intraoperative MVAs were determined by using PHT-method and 3D-planimetry method before and immediately after cardiopulmonary bypass (pre- and post-MVAPHT, and -MVA3D-planimetry). MVAs were also determined by using multi-detector computed tomographic scan (MDCT) before MVRep and within 7 days after MVRep (pre- and post-MVACT). MVAs determined by using three different methods were analysed. RESULTS: Mitral inflow pressure gradient (median [25th-75th percentile]) was significantly reduced after MVRep (3.0 [2.0-4.0] vs. 7.0 [6.0-9.0] mmHg; P<0.001). Pre-MVAPHT, pre-MVA3D-planimetry and preop-MVACT (mean [95% confidence interval]) did not differ significantly (1.08 [1.00-1.05], 1.08 [0.98-1.08], and 1.14 [1.07-1.22] cm2, respectively), but post-MVA3D-planimetry and post-MVACT (2.22 [2.07-2.36] and 2.31 [2.07-2.36] cm2, respectively) were significantly larger than post-MVAPHT (1.98 [1.83-2.13] cm2; P=0.007 and P<0.001, respectively). The correlation coefficient between post-MVA3D-planimetry and post-MVACT (0.59, P<0.01) was greater than that between post-MVAPHT and post-MVACT (0.39, P=0.01). CONCLUSIONS: These results support the clinical efficacy of 3D-planimetry for accurate evaluation of the MVA immediately after MVRep for severe MS, as a valuable alternative to PHT-method which usually underestimates MVA during this period.

What repeated measures analysis of variances really tells us.

This article examined repeated measures analysis of variance (RMANOVA). Within-subjects repeated measurements are unavoidable during clinical and experimental investigation, and between- and within-subject variability should be treated separately. Only through proper use and meticulous interpretation can ethical and scientific integrity be guaranteed. The philosophical background of, and knowledge pertaining to, RMANOVA are described in the first half of this text. The sphericity assumption and associated issues are discussed in the latter half. The final section provides a summary measure analysis, which was neglected by P value-dependent interpreters.

Efficacy and safety of Baweidihuang-wan in women with overactive bladder: a randomized, double blind, placebo controlled trial.

The aim of this study was to identify the efficacy and safety of Baweidihuang-wan (BWDH) in women with overactive bladder (OAB) and to investigate whether BWDH is more effective in OAB diagnosed as kidney yang deficiency pattern by the Korean medical pattern identification. The design of this study was a randomized, double blind, placebo controlled trial. One hundred eighty-six women with OAB were randomized to treatment (n=93) or control group (n=93). Participants received BWDH or placebo three times a day for eight weeks. Efficacy was assessed by overactive bladder symptom score and 3-day bladder diary. Subgroup analysis was conducted between kidney yang deficiency pattern and other patterns according to the Korean medical pattern identification. One hundred sixty-four participants completed this trial. The treatment group has improved in OABSS score, Total micturitions per 24 hr, Daytime micturitions per 24 hr, Total count of urgency, and Total urgency score over the control group, but differences were not statistically significant. By a subgroup analysis, OABSS score, total micturitions per 24 hr, total count of urgency and total urgency score improved most in the treatment group with the kidney yang deficiency pattern but this was also not statistically significant. No obvious adverse events were found in the use of BWDH. In conclusion, this trial did not show significant difference between BWDH and placebo in women with OAB. However BWDH tended to improve urinary frequency and urgency in OAB, especially diagnosed as kidney yang deficiency pattern. Further additional research will be needed.

Optimal effect-site concentration of remifentanil for preventing development of hypertension during tracheal intubation with inhaled desflurane induction.

BACKGROUND: The aim of the present study was to determine the effect-site concentration of remifentanil needed to prevent haemodynamic instability during tracheal intubation with inhaled desflurane induction. METHODS: One hundred American Society of Anesthesiologists I and II female patients were randomized to receive an effect-site concentration of remifentanil of 0, 1, 2, 3, or 4 ng/ml. Induction of anaesthesia was started with intravenous injection of propofol 2 mg/kg. Ninety seconds after the completion of propofol injection, rocuronium (0.8 mg/kg) and remifentanil were administered simultaneously with 3% desflurane inhalation. Tracheal intubation was attempted 150 sec after the commencement of remifentanil administration. RESULTS: A probit model of remifentanil concentration was predictive of successful intubation without development of hypertension (P for goodness-of-fit = 0.419). The effect-site concentration of remifentanil needed to achieve successful intubation without development of hypertension in 95% of the patients was 3.3 ng/ml (95% confidence interval, 2.6-4.8 ng/ml). CONCLUSIONS: The effect-site concentration of remifentanil of 3.3 ng/ml is effective in blunting the haemodynamic response in 95% of the patients when 2.0 mg/kg of propofol induction was followed by 3% desflurane inhalation.