Frequently, we encounter the phenomenon of hysteresis in kinetic-dynamic modeling. The hysteresis loop in the concentration-effect curve suggests a time discrepancy caused by various pharmacokinetic and pharmacodynamic factors. To collapse the hysteresis loop and to simplify the concentration-effect relationship, several kinetic-dynamic modeling approaches including the effect compartment link model, turnover model (indirect response model), and tolerance/rebound model, have been used. The semicompartmental model is one method to describe the hysteresis of the pharmacokineticpharmacodynamic relationship. Furthermore, this semi-compartmental model differs from other models (full parametric approaches) as it does not require pharmacokinetic parameters to estimate pharmacodynamic parameters and ke0. Therefore, we could employ a semi-compartmental approach in case it is difficult to apply the compartment model to pharmacokinetic data, as required for the pharmacodynamic analysis of inhalational anesthetics.

No abstract available.
Anesthesia, Spinal*

Central venous catheterization is a useful method for monitoring central venous pressure and maintaining volume status. However, it is associated with several complications, such as pneumothorax, hydrothorax, hemothorax, and air embolism. Here we describe a case of iatrogenic tension hydrothorax after rapid infusion of fluid into the pleural space, following the misplacement of an internal jugular vein catheter. Despite ultrasonographic guidance during insertion of the central venous catheter, we were not able to avoid malposition of the catheter. The patient went into hemodynamic compromise during surgery, necessitating chest tube drainage and a mechanical ventilator postoperatively. This case shows that central venous catheter insertion under ultrasonographic guidance does not guarantee proper positioning of the catheter.
Catheterization, Central Venous ; Catheters ; Central Venous Catheters* ; Central Venous Pressure ; Chest Tubes ; Drainage ; Embolism, Air ; Hemodynamics ; Hemothorax ; Humans ; Hydrothorax* ; Jugular Veins ; Methods ; Pneumothorax ; Ventilators, Mechanical

No abstract available.
Esophagitis* ; Nitric Oxide ; Sucralfate*

BACKGROUND: Approximately 90%~99% of ultraviolet A (UVA) ray reaches the Earth's surface. The deeply penetrating UVA rays induce the formation of reactive oxygen species (ROS), which results in oxidative stress such as photoproducts, senescence, and cell death. Thus, UVA is considered a primary factor that promotes skin aging. OBJECTIVE: Researchers investigated whether pretreatment with ferulic acid protects human dermal fibroblasts (HDFs) against UVA-induced cell damages. METHODS: HDF proliferation was analyzed using the water-soluble tetrazolium salt assay. Cell cycle distribution and intracellular ROS levels were assessed by flow cytometric analysis. Senescence was evaluated using a senescence-associated β-galactosidase assay, while Gadd45α promoter activity was analyzed through a luciferase assay. The expression levels of superoxide dismutase 1 (SOD1), catalase (CAT), xeroderma pigmentosum complementation group A and C, matrix metalloproteinase 1 and 3, as well as p21 and p16 were measured using quantitative real-time polymerase chain reaction. RESULTS: Inhibition of proliferation and cell cycle arrest were detected in cells that were irradiated with UVA only. Pretreatment with ferulic acid significantly increased the proliferation and cell cycle progression in HDFs. Moreover, ferulic acid pretreatment produced antioxidant effects such as reduced DCF intensity, and affected SOD1 and CAT mRNA expression. These effects were also demonstrated in the analysis of cell senescence, promoter activity, expression of senescent markers, and DNA repair. CONCLUSION: These results demonstrate that ferulic acid exerts protective effects on UVA-induced cell damages via anti-oxidant and stress-inducible cellular mechanisms in HDFs.
Aging ; Animals ; Antioxidants ; Catalase ; Cats ; Cell Aging ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Death ; Complement System Proteins ; DNA Repair ; Fibroblasts* ; Humans* ; Luciferases ; Matrix Metalloproteinase 1 ; Oxidative Stress ; Reactive Oxygen Species ; Real-Time Polymerase Chain Reaction ; RNA, Messenger ; Skin Aging ; Superoxide Dismutase ; Ultraviolet Rays ; Xeroderma Pigmentosum

OBJECTIVES: In vestibular neuritis (VN), the lesion preferentially affects the superior vestibular nerve because of the anatomic arrangement. It is well known that VN patients have a higher score of metabolic syndrome or a higher incidence of vertebral artery hypoplasia than controls. However, it is unclear whether the frequency of cardiovascular risk factors can affect the selective involvement of the branch of the vestibular nerve. Thus, we investigated the influence of cardiovascular risk factors on the development of total- or divisional VN. METHODS: 61 patients with VN were enrolled. Video head impulse tests and caloric tests were performed to determine which vestibular divisionswere affected. The patients were divided into divisional-VN (superior or inferior) and total-VN groups. Statistical analysis of the frequency of cardiovascular risk factors was performed only in superior and total VN groups because the number of inferior VN patients was too small to be statistically analyzed. RESULTS: Nineteen (31.1%) patients were classified as the total-VN group. In the divisional-VN group (42 patients, 65.6%), 40 were superior VN. The frequency of cardiovascular risk factors are not significantly different in superior VN and total-VN groups (All patients 50/61 [82.0%], superior-VN 36/40 [90.0%], total-VN 13/19 [68.4%]). The frequency of having more than one cardiovascular risk factor was slightly higher in the superior VN group, (13 [68.4%] vs. 36 [90.0%], p=0.062) but did not show any significant difference. CONCLUSIONS: The number of cardiovascular risk factors did not differ in superior VN patients compared to total VN patients.
Caloric Tests ; Cardiovascular Diseases ; Head Impulse Test ; Humans ; Incidence ; Risk Factors ; Vertebral Artery ; Vestibular Nerve ; Vestibular Neuronitis

Forced-air warming is commonly utilized to prevent perioperative hypothermia. Underbody warming blankets are often employed to secure a larger area for patient warming. While forced-air warming systems are generally regarded as safe, improper usage poses a risk of cutaneous complications. Additionally, the influence of underbody blankets on cutaneous complications remains uncertain. We present a case of cutaneous complications resulting from the improper utilization of a forced-air warming device and an underbody blanket. A 79-year-old man presented to the hospital for robotic proctectomy under general anesthesia. The surgery lasted for 7 hours, and the forced-air warming device with underbody blanket operated continuously for 5 hours intraoperatively. The surgery was completed without any incidents. However, first-degree burns on the patient’s back, along with superficial decubitus ulcers on his right scapula, were observed after surgery. To prevent cutaneous complications, clinicians must adhere to the manufacturer's guidelines when utilizing a forced-air warming system. Compared to overbody blankets, underbody blankets have limitations in monitoring cutaneous responses. Ensuring patient safety requires selecting an appropriate blanket for scheduled operations.

Background: Vocal cord paralysis (VCP) is one of the most stressful experiences for patients undergoing general anesthesia. Moreover, it is a risk factor for aspiration pneumonia and may increase morbidity and mortality. We examined several clinical features of the condition by reviewing the medical records of patients who experienced VCP following general anesthesia. Methods: We reviewed the medical records of 321 patients who consulted an otolaryngologist owing to hoarseness, sore throat, throat discomfort, or dysphagia after general anesthesia. Among these, we included in the present study 43 patients who were diagnosed with VCP by laryngoscopy, who did not have symptoms of suspected VCP before surgery, who had no past history of VCP, and for whom endotracheal intubation was not continued after surgery. Results: The mean age of patients with VCP was 51.28 years. With respect to surgical site, the most common was upper limb surgery, performed in 12 cases (9 cases were performed in sitting posture. With respect to surgical duration, only 11 cases lasted less than 3 h, whereas 32 cases required a surgical duration longer than 3 h. The most common symptom of VCP was hoarseness. Nine of the patients with VCP recovered spontaneously, but VCP persisted in 13 cases until the final follow-up examination. Conclusions We hope that this study might call attention to the occurrence of VCP following general anesthesia. Moreover, it is necessary to further evaluate the reasons for the higher incidence of VCP in upper limb surgery performed in sitting posture.

Background: Higher levels of anxiety increase the risks of surgery, including morbidity and mortality. The objectives of this study were to measure anxiety and depression during the preoperative period and to identify the degree of knowledge and concerns of older patients and their family protectors regarding anesthesia, and the causes of these concerns. Methods: We administered a questionnaire to older patients scheduled to undergo surgery and their family protectors one day prior to the surgery. The questionnaire included tools for quantifying anxiety and depression (Anxiety-Visual Analogue Scale, the Amsterdam Preoperative Anxiety and Information Scale, State-Trait Anxiety Inventory Korean YZ Form, and Short Form Geriatric Depression Scale). We also asked about the concrete causes of anxiety using pre-created forms. Results: There were 140 older patients and family protectors who participated in the study. The majority of older patients (n = 114, 81.4%) undergoing surgery and their family protectors (n = 114, 81.4%) indicated that they were anxious. Most of the older patients and their family protectors responded that they had insufficient knowledge about anesthesia, and they were mostly worried about failure to awaken following surgery, and postoperative pain. Older patients with higher anxiety scores showed higher depression scores. There were significant differences in depression scores depending on the presence of cohabitating family members. Conclusions It is important to remember that older patients with higher depression scores have higher anxiety during the preoperative period.

Background: This clinical trial was conducted to determine whether combined use of magnesium sulfate and vitamin C more significantly reduced postoperative fentanyl consumption and pain than magnesium sulfate or vitamin C alone. Methods: The prospective, double-blinded, randomized controlled study enrolled 132 patients scheduled for laparoscopic gynecologic surgery. The patients were randomly allocated to one of the four groups (n = 33 for each group; Group M [magnesium sulfate 40 mg/kg], Group V [vitamin C 50 mg/kg], Group MV [magnesium sulfate 40 mg/kg and vitamin C 50 mg/kg] and Group C [isotonic saline 40 ml]). Cumulative postoperative fentanyl consumption (primary endpoint measure), postoperative pain score by numeric rating scale, and postoperative nausea and vomiting were recorded at 1, 6, 24, and 48 h after discharge from the postanesthesia care unit. Results: Cumulative postoperative fentanyl consumption was significantly less in Groups M, V, and MV than in Group C at all time points. Group MV showed significantly less cumulative postoperative fentanyl consumption than Group M at postoperative 24 h (mean ± standard deviation, 156.6 ± 67.5 vs. 235.6 ± 94.6 μg, P = 0.001), as well as significantly less consumption than Groups M and V at postoperative 48 h (190.8 ± 74.6 vs. 301.0 ± 114.8 or 284.1 ± 128.6 μg, P < 0.001, P = 0.003, respectively). Conclusions Combined use of magnesium sulfate and vitamin C provides an additional benefit in postoperative pain management after laparoscopic gynecologic surgery in comparison to single administration of magnesium sulfate or vitamin C.