BACKGROUND: Elevated blood pressures during emergence from general anesthesia in patients with hypertension often result in undesirable complications such as myocardial ischemia, intracranial hemorrhages. The aim of this study was to assess the effect of intracuff 4% lidocaine on the dosage of nitroglycerine required to maintain the stable blood pressure during peri-extubation period in patients with hypertension. METHODS: Forty-nine patients scheduled for elective surgery were randomly allocated to group 1 and 2. We filled endotracheal tube's cuff with normal saline for group 1 and with 4% lidocaine for group 2. Blood pressures and heart rates were recorded before operation, during emergence, and after extubation. Nitroglycerine infusion was adjusted to maintain systolic blood pressure below 150 mmHg. Total infused dosages of nitroglycerine were recorded during operation and after stop of inhalational anesthetics for comparison of both groups' hemodynamic stability. RESULTS: Mean infused volume (microg/kg/min) of nitroglycerine during peri-extubation period was less in the group 2 than group 1. CONCLUSIONS: Intra-cuff 4% lidocaine in patients with hypertension during emergence from general anesthesia reduces the nitroglycerine dosage required to maintain hemodynamic stability.
Anesthesia, General ; Anesthetics ; Blood Pressure ; Heart Rate ; Hemodynamics* ; Humans ; Hypertension* ; Intracranial Hemorrhages ; Lidocaine* ; Myocardial Ischemia ; Nitroglycerin*

PURPOSE: To evaluate long-term change in intraocular pressure (IOP) in the fellow eyes after laser iridotomy and early phacoemusification with laser iridotomy in patients with acute angle-closure glaucoma. METHODS: We performed a retrospective, comparative chart review of 62 patients with acute angle-closure glaucoma; 35 patients (Group A) who underwent only prophylactic laser iridotomy on fellow eyes and 27 patients (Group B) who underwent prophylactic laser iridotomy and early phacoemusification on fellow eyes. Patients were followed up at 1 day, 1 week and 1, 3, 6 and 12 months. IOP change was analyzed after laser iridotomy 1 hour and at every follow-up. In addition, visual acuity and complications of laser iridotomy and phacoemusification were determined. RESULTS: In Group A, the mean IOP increase in fellow eyes occurred within 1 month after laser iridotomy (initial, 15.9 ± 5.0 mm Hg; final, 15.9 ± 2.6 mm Hg), However, in Group B, the mean IOP of fellow eyes was maintained up to 12 months without an increase in IOP (initial, 17.0 ± 3.3 mm Hg; final, 13.3 ± 2.8 mm Hg) Among the fellow eyes, 13 patients in Group A (37.14%) and 4 patients in Group B (14.81%, p = 0.032) underwent further medical therapy. The initial visual acuity of fellow eyes in Group A was 0.78 ± 0.21 and 0.71 ± 0.22 in Group B, and at the final visit, 0.73 ± 0.31 in Group A and 0.93 ± 0.27 in Group B (p = 0.003). CONCLUSIONS: We found that most fellow eyes treated with laser iridotomy and phacoemulsification maintained satisfactory IOP and good vision. These results support that laser iridotomy and phacoemulsification in the fellow eye with acute angle-closure glaucoma is a reasonable prophylactic treatment.
Follow-Up Studies ; Glaucoma, Angle-Closure* ; Humans ; Intraocular Pressure* ; Phacoemulsification* ; Retrospective Studies ; Visual Acuity

This study explores the internal standards for hearing tests and benefits of implementing international standard protocols, including the International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC), and discusses how ISO and IEC standards provide a framework for designing, calibrating, assessing hearing test instruments and methods, and exchanging and comparing data globally. ISO and IEC standards for hearing tests improve accuracy, reliability, and consistency of test results by applying standardized methods and environments. Moreover, they promote international harmonization and data interoperability, enabling information exchange and research collaboration. Those standards for hearing tests are beneficial but have challenges and limitations, such as variation in equipment and calibration, lag in updating standards, variation in implementation and compliance, and lack of coverage of clinical aspects, cultural diversity, and linguistic diversity. These affect the quality and interpretation of test results. Adapting ISO or IEC standards locally would improve their applicability and acceptability, while balancing customization and compatibility with global standards.

Pure-tone audiometry, using an audiometer, is the fundamental hearing test for diagnosing hearing loss. The requirements of the devices and the detailed process for calibrating the related equipment are described in international standards. However, traceable calibration and uncertainty evaluation processes are not widely accepted or applied to the qualification and maintenance of audiometric equipment. Here, we briefly review standard measurement systems for audiometric devices and introduce their calibration procedures. The uncertainty of each calibration process was investigated, and its impact on hearing test results was considered. Our findings show that the traceability of each procedure can be secured, satisfying the uncertainty requirement and being sufficiently smaller than the permissible deviation from the audiometer requirement. To guarantee the objectivity and reliability of hearing tests and maintain low uncertainty, close cooperation and mutual understanding between the metrology field and the medical community are necessary.

The auditory brainstem response (ABR) is a noninvasive test that measures neural activity in response to auditory stimuli. Racial differences in head shape have provided strong evidence for specific normative data and accurate device calibration. International standards emphasize the need for standardized procedures and references. This study aimed to outline the standard procedure and related normative ABR values. Standard procedures were performed according to International Electrotechnical Commission (IEC) standards. Five studies from two countries were included to compare the normative values of the ABR. The dataset from the National Standard Reference Data Center (NSRDC) was used as reference. Normative values were described in terms of stimuli, latency, and amplitude. For click stimuli, the latency of the ABR showed different patterns across populations, such as those from Korea and the USA. Although the latencies reported by the NSRDC and for Koreans were relatively short, those reported for USA populations were longer. Using clicks, it was shown that the USA population had the largest ABR amplitude compared to those reported for the other two datasets. For Wave V latency using tone bursts, a similar pattern was identified with click stimuli. Frequency-specific trends were also observed. Although there is a lack of ABR datasets, the information and insights of the present study could be utilized as standard guidelines in research on ABR.

The auditory brainstem response (ABR) is a noninvasive test that measures neural activity in response to auditory stimuli. Racial differences in head shape have provided strong evidence for specific normative data and accurate device calibration. International standards emphasize the need for standardized procedures and references. This study aimed to outline the standard procedure and related normative ABR values. Standard procedures were performed according to International Electrotechnical Commission (IEC) standards. Five studies from two countries were included to compare the normative values of the ABR. The dataset from the National Standard Reference Data Center (NSRDC) was used as reference. Normative values were described in terms of stimuli, latency, and amplitude. For click stimuli, the latency of the ABR showed different patterns across populations, such as those from Korea and the USA. Although the latencies reported by the NSRDC and for Koreans were relatively short, those reported for USA populations were longer. Using clicks, it was shown that the USA population had the largest ABR amplitude compared to those reported for the other two datasets. For Wave V latency using tone bursts, a similar pattern was identified with click stimuli. Frequency-specific trends were also observed. Although there is a lack of ABR datasets, the information and insights of the present study could be utilized as standard guidelines in research on ABR.

The auditory brainstem response (ABR) is a noninvasive test that measures neural activity in response to auditory stimuli. Racial differences in head shape have provided strong evidence for specific normative data and accurate device calibration. International standards emphasize the need for standardized procedures and references. This study aimed to outline the standard procedure and related normative ABR values. Standard procedures were performed according to International Electrotechnical Commission (IEC) standards. Five studies from two countries were included to compare the normative values of the ABR. The dataset from the National Standard Reference Data Center (NSRDC) was used as reference. Normative values were described in terms of stimuli, latency, and amplitude. For click stimuli, the latency of the ABR showed different patterns across populations, such as those from Korea and the USA. Although the latencies reported by the NSRDC and for Koreans were relatively short, those reported for USA populations were longer. Using clicks, it was shown that the USA population had the largest ABR amplitude compared to those reported for the other two datasets. For Wave V latency using tone bursts, a similar pattern was identified with click stimuli. Frequency-specific trends were also observed. Although there is a lack of ABR datasets, the information and insights of the present study could be utilized as standard guidelines in research on ABR.

The auditory brainstem response (ABR) is a noninvasive test that measures neural activity in response to auditory stimuli. Racial differences in head shape have provided strong evidence for specific normative data and accurate device calibration. International standards emphasize the need for standardized procedures and references. This study aimed to outline the standard procedure and related normative ABR values. Standard procedures were performed according to International Electrotechnical Commission (IEC) standards. Five studies from two countries were included to compare the normative values of the ABR. The dataset from the National Standard Reference Data Center (NSRDC) was used as reference. Normative values were described in terms of stimuli, latency, and amplitude. For click stimuli, the latency of the ABR showed different patterns across populations, such as those from Korea and the USA. Although the latencies reported by the NSRDC and for Koreans were relatively short, those reported for USA populations were longer. Using clicks, it was shown that the USA population had the largest ABR amplitude compared to those reported for the other two datasets. For Wave V latency using tone bursts, a similar pattern was identified with click stimuli. Frequency-specific trends were also observed. Although there is a lack of ABR datasets, the information and insights of the present study could be utilized as standard guidelines in research on ABR.

Hearing thresholds provide essential information and references about the human auditory system. This study aimed to identify changing trends in distributions of hearing threshold levels across ages by comparing the International Organization for Standardization (ISO) 7029 and newly available data after publishing ISO 7029. To compare ISO 7029 and newly available hearing threshold data after publishing ISO 7029, four country-specific datasets that presented average hearing threshold levels under conditions similar to ISO 7029 were utilized. For frequencies between 125 Hz and 8,000 Hz, the deviations of hearing threshold values by ages from the hearing threshold of the youngest age group for each data point were utilized. For frequencies from 9,000 Hz to 12,500 Hz, the median threshold information was utilized. Hearing threshold data reported after publishing ISO 7029 from the four countries were mostly similar to the ISO 7029 data but tended to deviate in some age groups and sexes. As national hearing threshold trends change, the following ISO 7029 revision suggests the need to integrate hearing threshold data from different countries.