A Case of Auditory Neuropathy Caused by Pontine Hemorrhage in an Adult.

A pontine hemorrhage can evoke several neurological symptoms because the pons contains various nuclei and nerve fibers. Hearing loss can develop as a result of a pontine hemorrhage because there is an auditory conduction pathway in the cochlear nucleus of the pons. However, very few cases of hearing loss caused by pontine lesions have been reported, and there have been no reports of auditory neuropathy that developed following a pontine hemorrhage. Recently we had a patient who experienced a nontraumatic pontine hemorrhage who was diagnosed with auditory neuropathy. The 34-year-old male patient was admitted to the emergency department with sudden alteration of mental status. His brain computed tomographic imaging revealed a hemorrhage in the central pons. He complained of hearing difficulties after his mental status recovered through conservative treatment, but a pure-tone audiogram showed very mild hearing loss in both ears. Further hearing tests using otoacoustic emissions, which showed normal responses, and auditory brainstem responses, which showed no waveforms at maximum stimulus intensity, revealed that his hearing difficulties were caused by auditory neuropathy. This case implies that the threshold of sound detection can be preserved in patients with pontine hemorrhage who complain of hearing difficulties. Auditory neuropathy should be considered as a possible cause of hearing difficulties in these patients and appropriate hearing tests should be performed.

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.

Effectiveness of Electroconvulsive Therapy Augmentation on Clozapine-Resistant Schizophrenia.

OBJECTIVE: This retrospective case series study of the effectiveness of electroconvulsive therapy (ECT) augmentation on clozapine-resistant schizophrenia was conducted by EMR review. METHODS: Clozapine-resistance was defined as persistent psychotic symptoms despite at least 12 weeks of clozapine administration with blood levels over 350 ng/mL in order to rule out pseudo-resistance. Seven in-patients who were taking clozapine and treated with ECT were selected. We analyzed the psychopathology and subscales changed by ECT. RESULTS: The average number of ECT sessions was 13.4 (±4.6). Total Positive and Negative Syndrome Scale (PANSS) score was significantly reduced by 17.9 (±12.8) points (p=0.0384) on average, which represented a reduction of 25.5% (±14.3). 71.4% (5/7) of patients were identified as clinical remission, with at least a 20% reduction in PANSS score. PANSS reduction was associated with number of ECT sessions, stimulus level in the final session, and blood clozapine levels before ECT. However, the negative subscale on the PANSS were not reduced by ECT in any patient. We did not observe any persistent adverse cognitive effects. CONCLUSION: This study supports that ECT augmentation on clozapine-resistant schizophrenia reveals clinically effective and safe. Further research should be done involving a larger number of patients to investigate the effectiveness of clozapine/ECT combination therapy.

Cortical auditory evoked potential in aging: effects of stimulus intensity and noise.

OBJECTIVE: Older adults often have more difficulty understanding speech than younger adults do, particularly in the presence of noise. Such age-related speech perception difficulties may be related to declines in central auditory processing. Additionally, it has been hypothesized that impaired auditory processing might be related to neural dysynchrony. The purpose of this study was to examine the effects of stimulus intensity and noise on the N1-P2 response in younger and older normal-hearing adults. METHODS: Eight younger and 8 older normal-hearing adults participated in this study. Brief 100-ms tones (1.0 kHz, 100-60 dB SPL) in quiet and in continuous broadband noise (70 dB SPL) were used to evoke the N1-P2 responses. The N1-P2 components were analyzed as a function of stimulus intensity in both groups. RESULTS: N1 latencies to tones in quiet for older adults were delayed only at 60 dB SPL compared with those for younger adults. Additionally, N1 latencies to tones in noise were prolonged in older adults compared with those in younger adults even at 70 dB SPL (SNR = 0). No significant age effects were observed for the P2 latencies and N1-P2 amplitudes between the groups. CONCLUSION: N1 latency to tones with lower intensity and noise were delayed in older adults compared with those in younger adults. These stimulus intensity and noise issues can affect synchronized neural activity underlying the auditory processing and may provide a partial explanation for the difficulties shown by older adults in understanding speech.

Profound bradycardia with lidocaine during anesthesia induction in a silent sick sinus syndrome patient.

Sick sinus syndrome is caused by sinus node dysfunction that renders it unable to function as a pacemaker. Patients with sick sinus syndrome are often asymptomatic or have symptoms that are mild and nonspecific. Lidocaine (0.5 mg/kg) injection is used for reduction of pain associated with intravenous injection of propofol. Episodes of marked bradycardia with sinus arrest after prophylactic lidocaine injection are reported in a 69-y-old man with no apparent preoperative cardiac disease or electrocardiographic abnormality. Surgery was postponed, and he was later diagnosed with sick sinus syndrome.

Recovery function of electrically evoked compound action potential in implanted children with auditory neuropathy: preliminary results.

CONCLUSION: The results of this study show that the temporal processing ability in children with auditory neuropathy (AN) can be restored to some degree by electrical stimulation through a cochlear implant. In addition, the electrically evoked compound action potential (ECAP) may be a useful index to predict outcomes in implanted children with AN. OBJECTIVES: The purpose of this study was to evaluate restoration of the temporal processing abilities in implanted children with AN using ECAP recovery function and speech perception. METHODS: Ten children who had received cochlear implantations participated in this study, including six with AN and four with sensorineural hearing loss (SNHL). ECAP recovery functions were measured, and the slopes of ECAP recovery functions in implanted children with AN were compared with those of implanted children with SNHL. Open-set speech perception test scores of implanted children with AN were compared with those of 78 implanted children with SNHL. RESULTS: The slopes of the ECAP recovery function in children with AN did not differ significantly from those in children with SNHL. The group of children with robust ECAPs showed good postoperative performance. However, the group with no ECAPs showed poor performance.

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.

Emergence cerebral oxygen desaturation without hemodynamic compromise in pediatric patients.

BACKGROUND: The regional cerebral oxygen saturation (rSO(2)) decreases significantly during ordinary anesthetic recovery in pediatric patients anesthetized with sevoflurane or desflurane. The present study examined the relationship between rSO(2) and the clinical parameters associated with the degree of anesthetic recovery. METHODS: Twelve pediatric patients with American Society of Anesthesiologists physical status 1 were assigned randomly to receive anesthesia with sevoflurane or desflurane. All children underwent general anesthesia for minor surgery. After surgery, the rSO(2), the age-adjusted MAC fraction of anesthetic concentration (F(E)), and the bispectral index (BIS) were recorded over a 10-minute period. The correlations between rSO(2) and candidate predictors, such as F(E), BIS, anesthetic, and duration of anesthesia, were analyzed. RESULTS: All children recovered uneventfully. The lowest observed rSO(2) reached 63% and the maximum decrease in rSO(2) was 24%. The mean blood pressure and heart rate were maintained within clinical ranges. The decrease in rSO(2) correlated positively with the F(E) (r = 0.25, P = 0.00) and the duration of anesthesia (r = 0.24, P = 0.01), and inversely with the use of sevoflurane (r = -0.30, P = 0.00). CONCLUSIONS: Despite normal parameters, cerebral desaturation occurred during the emergence of ordinary general anesthesia even without hemodynamic compromise or arterial desaturation. Cerebral desaturation might be associated with the degree of anesthetic recovery and the use of sevoflurane.

Sauchinone, a lignan from Saururus chinensis, reduces tumor necrosis factor-alpha production through the inhibition of c-raf/MEK1/2/ERK 1/2 pathway activation.

We investigated the anti-inflammatory effects of sauchinone, a lignan isolated from Saururus chinensis, and the underlying mechanism in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. To assess the effects of sauchinone on LPS-induced macrophages activation, we measured the production of tumor necrosis factor (TNF)-alpha and macrophage inflammatory protein (MIP)-2, and activation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase (ERK) 1/2, c-Jun amino terminal kinases and p38 mitogen-activated protein kinase, and NF-kappaB activation in RAW264.7 cells. Sauchinone decreased the production of TNF-alpha, but not MIP-2 production in RAW264.7 cells stimulated with LPS. Sauchinone also decreased c-Raf-MEK1/2-ERK1/2 phosphorylation and NF-kappaB activation in RAW264.7 cells stimulated with LPS. Our results show that sauchinone inhibits LPS-induced TNF-alpha expression in macrophages by suppression of NF-kappaB activation via ERK1/2 pathway, which may constitute anti-inflammatory effects of sauchinone.

Performance of children with mental retardation after cochlear implantation: speech perception, speech intelligibility, and language development.

CONCLUSION: Children with mental retardation (MR) obtain demonstrable benefit from cochlear implantation, and their postoperative performance was tempered by the degree of MR. OBJECTIVE: The purpose of this study was to investigate the performance of children with MR after implantation, and to explore their progress according to the degree of MR. METHODS: Fifteen implanted children with MR were included. Progress in speech perception, speech intelligibility, and language was measured using Categories of Auditory Performance, monosyllabic word test, Speech Intelligibility Rating, and Language Scale before and after implantation. We retrospectively examined outcomes and explored the association between the progress and the degree of MR after implantation. We compared monosyllabic word test scores using repeated-measures ANOVA. RESULTS: Speech perception and speech intelligibility for children with mild MR improved consistently after implantation. After implantation, monosyllabic word test scores did not differ significantly between children with mild MR and children with no additional disabilities. Although language development of children with mild MR was slow, they could communicate verbally 3 years after implantation. Children with moderate MR progressed more slowly and had limitations in speech and language development, and these children could communicate by vocalization and gesture 3 years after implantation.

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.

How much are patients willing to pay for prevention of postoperative nausea and vomiting?.

BACKGROUND: Postoperative nausea and vomiting (PONV) remains a common complication of anesthesia. We tried to assess the amount patients were willing to pay for a hypothetical antiemetic that would completely prevent PONV. METHODS: Trained residents interviewed 86 patients, who were scheduled to undergo general anesthesia, and questionnaires were completed. RESULTS: Patients were willing to pay a median of 30,000 won for an antiemetic that would completely prevent PONV. The amounts patients were willing to pay correlated with age, previous history of PONV, and patient income. CONCLUSIONS: Patients assigned a value for avoidance of PONV. It is suggested that more efforts to prevent PONV would be helpful for the increase in patient satisfaction.

Prediction of plasma hemoglobin concentration by near-infrared spectroscopy.

The estimation of plasma hemoglobin concentration (Hb) is among one of the daily activities in the practice of clinical anesthesiology. The near-infrared spectroscopy of the brain (rSO(2)) represents a balance between cerebral oxygen delivery and consumption. This study was designed to assess the value of rSO(2) in the prediction of the Hb level while other variables were mathematically controlled. Thirty healthy adult patients undergoing spine surgery, expected to have a moderate degree of intraoperative bleeding, were enrolled in this study. General anesthesia was given and ventilation was mechanically controlled. Measurement of Hb and PaCO(2) were performed at random periods of time. We obtained a total of 97 data combinations for the 30 study patients. The Hb was regressed by independent variables including rSO(2) and PaCO(2). A multilinear regression analysis was performed and the final regression equation was expressed only with statistically significant variables. The measured Hb was tightly regressed with three variables. The final regression equation was Hb=+8.580+0.238.rSO(2)-0.338.PaCO(2)-0.004.anesthetic exposure duration (Tmin) (p=0.000, r(2)=0.809). Near-infrared spectroscopy was shown to be a valuable predictor of plasma Hb in the clinical anesthesiology setting.