Effects of Bilateral Infraorbital and Infratrochlear Nerve Block on Emergence Agitation after Septorhinoplasty: A Randomized Controlled Trial

Emergence agitation is common after septorhinoplasty, and postoperative pain is the main risk factor for this condition. Infraorbital and infratrochlear nerve block have been reported to facilitate pain management in patients after nasal procedures. The effect of peripheral nerve block on the incidence of emergence agitation has not been evaluated. Sixty-six patients that were scheduled for septorhinoplasty were assigned to receive bilateral infraorbital and infratrochlear nerve block with either 8 mL of 0.5% ropivacaine (Block group) or isotonic saline (Sham Block group). The incidence of emergence agitation was evaluated using the Riker sedation-agitation scale. Analgesic consumption, hemodynamic parameters, postoperative pain scores, adverse events, and patient satisfaction with analgesia were evaluated. The incidence of emergence agitation was lower in the Block group than in the Sham Block group (6 (20.0%) versus 20 (62.5%), p = 0.002). The mean intraoperative remifentanil consumption was lower in the Block group than in the Sham Block group (0.074 ± 0.014 μg/kg/min. versus 0.093 ± 0.019 μg/kg/min., respectively, p < 0.0001), as was the proportion of patients that needed postoperative tramadol administration and median postoperative pain score at 0-2 h after surgery (9 (30.0%) versus 21 (65.6%), p = 0.011; 3.0 (2.0-4.0) versus 4.0 (3.0-4.0), p < 0.0001, respectively). Hemodynamic parameters and the incidence of adverse events were similar between the two groups. The median patient satisfaction score with respect to analgesia was higher in the Block group than in the Sham Block group (3.5 (3.0-4.0) versus 3.0 (3.0-4.0), respectively, p = 0.034). The preoperative bilateral infraorbital and infratrochlear nerve block decreased the incidence of emergence agitation after septorhinoplasty.ope

북중무역: 집계 데이터와 기업수준 데이터를 통한 분석

학위논문 (박사)-- 서울대학교 대학원 : 경제학부, 2014. 8. 김병연.This dissertation uses firm-level as well as aggregate data to investigate the economic relationships between North Korea and China. More specifically, it analyzes the effects of North Korea-China trade on the economic growth of North Korea. It further discusses the impacts of sanctions by South Korea and Japan on North Korea-China trade. Finally it estimates the determinants of the performance of firms that are trading with North Korea in China Chapter 2 uses cointegration tests and Vector Error Correction Model (VECM) to examine causality between Sino-North Korean trade and economic growth of North Korea from 1970 to 2012. To carry out empirical analysis, VECM is constructed, which is comprised of four variables, GDP, exports, imports, and investment. Investment is used as the key explanatory variable of economic growth, and imported capital as a proxy of investment. The cointegration equation suggests that the mechanism of North Koreas economic growth is basically similar with that of low income, market-oriented countries, in the sense that trade and foreign capital inflows do matter for its growth. The estimation of the VECM shows that, in the long-run, exports, imports, and investments Granger-cause income through error correction mechanism, but not vice versa. With respect to short-term causality, however, the variables have little causal relations with each other except for causality flows from imports to exports. This shows that traditional barter-type settlement is still prevalent in Sino-North Korean trade. Chapter 3 addresses the question whether North Korea–China trade dilutes the effects of the unilateral sanctions imposed by South Korea and Japan, and if so, to what extent and in what way. It finds structural adjustment of North Koreas export pattern in size and trade type for the purpose of diluting the effectiveness of the unilateral sanctions, imposed by South Korea in particular. It also finds that South Koreas economic sanctions significantly boost North Koreas exports to China, and the export increase has been large enough to cover the loss from South Koreas sanctions. In particular, North Korea has increased both exports to the Chinese domestic market (through general trade) and exports transferred in China (through bonded trade). These findings show that North Korea has mitigated the economic damage of sanctions by employing a broad range of techniques for trade diversion. The changes would take place because incentives of both North Korean regime and foreign firms meet well particularly after South Korean sanctions. Finally, Chapter 4 identifies the determinants of Chinese firms performance by using the survey data of the firms that trade with North Korea in Dandong, China. The survey was conducted in 2012 and 2013 to assess the impact of the sanctions imposed by South Korea in 2010. 138 firms engaged in trade with North Korea are used in the analysis out of 174 sample firms. With special attention paid to the firms relationships with their North Korean partners, it finds that the business ties with army-affiliated North Korean counterparts have a stronger positive effect on the performance of Chinese firms than the ties with other counterparts. In particular, the business ties between the Han zu companies and the army-affiliated North Korean partners are found to be the most influential. This empirical finding suggests that North Koreas military first polices de facto regulates resource allocation mechanisms in North Koreas export sectors, after the imposition of South Korean sanctions. It also finds that Chinese firms that have more partners and formal dispute resolution channels tend to achieve more favorable outcomes in cross-border exchanges with North Korea, because these features function as hedge against the risk from North Koreas unstable Wa-Ku system. The following chapters are all self-contained and can be read independently.Chapter 1. Introduction 1 1. Motivation 1 2. Objectives and Methodology 3 Chapter 2. Economic Growth and Trade of North Korea with China: Cointegration and Granger Causality Test 6 1. Introduction 6 2. Data 11 2.1 GDP 12 2.2 Investment 13 2.3 Trade Data with China 17 3. Hypotheses 18 3.1 Conventional Socialism Hypothesis 18 3.2 Hypothesis Based on Conventional Growth Theory 20 3.3 Export-Led Growth Hypothesis 22 4. Empirical Results 22 4.1 Unit root tests 22 4.2 Tests for Optimal Order Length 23 4.3 Cointegration 24 4.4 Granger Causality Tests 28 4.5 Parameter stability test 31 5. Conclusion 37 References 39 Appendix 1: Bounds test procedures 41 Chapter 3. The Impact of Economic Sanctions on North Korea – China Trade: A Dynamic Panel Analysis 43 1. Introduction 43 2. Empirical Framework 47 3. Data 53 4. Empirical Results 55 4.1 Basic Model: Sanctions Effects on Total Exports 55 4.2 Extended Model: Sanctions Effects by Trade Type 58 5. Conclusion 64 References 67 Appendix 1: Economic Sanctions of South Korea and Japan on North Korea 70 Appendix 2: China Customs Trade Types (Customs Regimes) and Codes 71 Chapter 4. The Performances of Chinese Firms in North Korean Trade: Evidence from Firm-Level Data 72 1. Introduction 72 2. Hypotheses 74 2.1 Business ties with North Korean partners 74 2.2 Market linkage 76 3. The Survey and Descriptive Statistics 77 3.1 Outline of Survey 77 3.2 Descriptive Statistics 79 4. The Model 83 5. The Results 85 5.1 Basic Regressions 85 5.2 Interaction effects 90 6. Conclusion 92 References 95 Appendix 1: Graphic Representation of Chinese Firms Business network with its North Korean partners 97 Appendix 2: Graphic Representation of Chinese Firms Market linkage 103 Chapter 5. Conclusion 106Docto

Ability of Carotid Corrected Flow Time to Predict Fluid Responsiveness in Patients Mechanically Ventilated Using Low Tidal Volume after Surgery

Predicting fluid responsiveness in patients under mechanical ventilation with low tidal volume (VT) is challenging. This study evaluated the ability of carotid corrected flow time (FTc) assessed by ultrasound for predicting the fluid responsiveness during low VT ventilation. Patients under postoperative mechanical ventilation and clinically diagnosed with hypovolemia were enrolled. Carotid FTc and pulse pressure variation (PPV) were measured at VT of 6 and 10 mL/kg predicted body weight (PBW). FTc was calculated using both Bazett's (FTcB) and Wodey's (FTcW) formulas. Fluid responsiveness was defined as a ≥15% increase in the stroke volume index assessed by FloTrac/Vigileo monitor after administration of 8 mL/kg of balanced crystalloid. Among 36 patients, 16 (44.4%) were fluid responders. The areas under the receiver operating characteristic curves (AUROCs) for the FTcB at VT of 6 and 10 mL/kg PBW were 0.897 (95% confidence interval [95% CI]: 0.750-0.973) and 0.895 (95% CI: 0.748-0.972), respectively. The AUROCs for the FTcW at VT of 6 and 10 mL/kg PBW were 0.875 (95% CI: 0.722-0.961) and 0.891 (95% CI: 0.744-0.970), respectively. However, PPV at VT of 6 mL/kg PBW (AUROC: 0.714, 95% CI: 0.539-0.852) showed significantly lower accuracy than that of PPV at VT of 10 mL/kg PBW (AUROC: 0.867, 95% CI: 0.712-0.957; p = 0.034). Carotid FTc can predict fluid responsiveness better than PPV during low VT ventilation. However, further studies using automated continuous monitoring system are needed before its clinical use.ope

Effects of the Type of Intraoperative Fluid in Living Donor Kidney Transplantation: A Single-Center Retrospective Cohort Study

Purpose: Perioperative fluid management in kidney transplant recipients is crucial to supporting the fluid, acid-base, and electrolyte balance required for graft perfusion. However, the choice of intraoperative crystalloids in kidney transplantation remains controversial. We conducted a single-center retrospective cohort study to evaluate the impact of intraoperative fluids on acid-base and electrolyte balance and graft outcomes. Materials and methods: We included 282 living donor kidney transplant recipients from January 2010 to December 2017. Patients were classified into two groups based on the type of intraoperative crystalloids used (157 patients in the half saline group and 125 patients in the balanced crystalloid solutions group, Plasma-lyte). Results: Compared with the half saline group, the Plasma-lyte group showed less metabolic acidosis and hyponatremia during surgery. Hyperkalemia incidence was not significantly different between the two groups. Changes in postoperative graft function assessed by blood urea nitrogen and creatinine were significantly different between the two groups. Patients in the Plasma-lyte group exhibited consistently higher glomerular filtration rates than those in the half saline group at 1 month and 1 year after transplantation after adjusting for demographic differences. Conclusion: Intraoperative Plasma-lyte can lead to more favorable results in terms of acid-base balance during kidney transplantation. Patients who received Plasma-lyte showed superior postoperative graft function at 1 month and 1 year after transplantation. Further studies are needed to evaluate the superiority of intraoperative Plasma-lyte over other types of crystalloids in relation to graft outcomes.ope

Assessment of Noise Exposure and Its Characteristics in the Intensive Care Unit of a Tertiary Hospital

Noise generated in the intensive care unit (ICU) adversely affects both critically ill patients and medical staff. Recently, several attempts have been made to reduce ICU noise levels, but reliable and effective solutions remain elusive. This study aimed to provide evidence on noise distributions in the ICU to protect patient health. For one week, we measured noise levels in isolated rooms, open units, and nursing stations in medical, surgical, and pediatric ICUs, respectively. We additionally analyzed the noise generated by medical equipment that is frequently used in ICUs. The median (interquartile range) noise exposure level (dBA) of all ICU units was 54.4 dB (51.1-57.5) over 24 h. The highest noise exposure was noted in the surgical ICU's daytime open unit at 57.6 dB (55.0-61.1). Various ICU medical devices continuously generated low-frequency noise. Mechanical noise levels ranged from a minimum of 41 dB to a maximum of 91 dB. It was also confirmed that patient-monitoring devices generated loud, high-frequency noise at 85 dB. ICU noise levels were much higher than expected. Noise reduction that focuses on behavior modification of medical staff has limited potential; instead, structural improvements should be considered to reduce the transmission of noise.ope

Inhalation sedation for postoperative patients in the intensive care unit: initial sevoflurane concentration and comparison of opioid use with propofol sedation

Background: Although the use of volatile sedatives in the intensive care unit (ICU) is increasing in Europe, it remains infrequent in Asia. Therefore, there are no clinical guidelines available. This study investigates the proper initial concentration of sevoflurane, a volatile sedative that induces a Richmond agitation-sedation scale (RASS) score of -2 to -3, in patients who underwent head and neck surgery with tracheostomy. We also compared the amount of postoperative opioid consumption between volatile and intravenous (IV) sedation. Methods: We planned a prospective study to determine the proper initial sevoflurane concentration and a retrospective analysis to compare postoperative opioid consumption between volatile sedation and propofol sedation. Patients scheduled for head and neck surgery with tracheostomy and subsequent postoperative sedation in the ICU were enrolled. Results: In this prospective study, the effective dose 50 (ED50) of initial end-tidal sevoflurane concentration was 0.36% (95% confidence interval [CI], 0.20 to 0.60%), while the ED 95 was 0.69% (95% CI, 0.60 to 0.75%) based on isotonic regression methods. In this retrospective study, remifentanil consumption during postoperative sedation was significantly lower in the sevoflurane group (2.52±1.00 µg/kg/hr, P=0.001) than it was in the IV propofol group (3.66±1.30 µg/kg/hr). Conclusions: We determined the proper initial end-tidal concentration setting of sevoflurane for patients with tracheostomy who underwent head and neck surgery. Postoperative sedation with sevoflurane appears to be a valid and safe alternative to IV sedation with propofol.ope

A Rare Case of Aggravated Hypercalcemia of Malignancy After Surgery

Paraneoplastic syndromes are caused by ectopic hormone production in malignant tumors. Hypercalcemia of malignancy is the main manifestation of paraneoplastic syndromes and can lead to acute kidney injury, life-threatening arrhythmia, and cardiac arrest. Here, we present a 70-year-old Asian female with a probable diagnosis of advanced lung cancer with hypercalcemia of malignancy. She underwent surgery to treat a pathologic fracture of the humerus. In this case, hypercalcemia of malignancy was unexpectedly aggravated after surgery, and hypercalcemic complications led to a poor outcome for the patient.ope

Perioperative respiratory adverse events in children with active upper respiratory tract infection who received general anesthesia through an orotracheal tube and inhalation agents

BACKGROUND: Active upper respiratory tract infection (URI), orotracheal intubation and use of inhalation anesthetics are known risk factors for perioperative respiratory adverse events (RAE). This study investigated the risk factors of perioperative RAE in children with these risk factors. METHODS: The records of 159 children who underwent general anesthesia with an orotracheal tube and inhalation were reviewed. These patients also had at least one of the following URI symptoms on the day of surgery: clear or green nasal secretion, dry or moist cough, nasal congestion, or fever. RAE such as laryngospasm, bronchospasm, oxygen desaturation and sustained cough were collected before induction, during intubation, during extubation, after extubation and in the postanesthesia care unit. RESULTS: Forty-five patients had RAE. The patients with RAE were younger than those without RAE. There were more passive smokers and a greater number of intubation attempts in patients with RAE than in those without RAE. The type of surgery and type of inhalation agents were not different between patients with and without RAE. Passive smoking was the only independent risk factor for RAE. CONCLUSIONS: In children with an active URI using orotracheal tube and inhalation anesthetics, passive smoking is an important risk factor for RAE.ope

Predicting graft failure in pediatric liver transplantation based on early biomarkers using machine learning models

The early detection of graft failure in pediatric liver transplantation is crucial for appropriate intervention. Graft failure is associated with numerous perioperative risk factors. This study aimed to develop an individualized predictive model for 90-days graft failure in pediatric liver transplantation using machine learning methods. We conducted a single-center retrospective cohort study. A total of 87 liver transplantation cases performed in patients aged < 12 years at the Severance Hospital between January 2010 and September 2020 were included as data samples. Preoperative conditions of recipients and donors, intraoperative care, postoperative serial laboratory parameters, and events observed within seven days of surgery were collected as features. A least absolute shrinkage and selection operator (LASSO) -based method was used for feature selection to overcome the high dimensionality and collinearity of variables. Among 146 features, four variables were selected as the resultant features, namely, preoperative hepatic encephalopathy, sodium level at the end of surgery, hepatic artery thrombosis, and total bilirubin level on postoperative day 7. These features were selected from different times and represent distinct clinical aspects. The model with logistic regression demonstrated the best prediction performance among various machine learning methods tested (area under the receiver operating characteristic curve (AUROC) = 0.898 and area under the precision-recall curve (AUPR) = 0.882). The risk scoring system developed based on the logistic regression model showed an AUROC of 0.910 and an AUPR of 0.830. Together, the prediction of graft failure in pediatric liver transplantation using the proposed machine learning model exhibited superior discrimination power and, therefore, can provide valuable information to clinicians for their decision making during the postoperative management of the patients.ope

Family caregivers' responses to a visitation restriction policy at a Korean surgical intensive care unit before and during the coronavirus disease 2019 pandemic

Background: Since the COVID-19 pandemic, restricting family visits in the ICU has increased concerns regarding negative psychosocial consequences to patients and families. Objectives: To compare the quality of life, depressive symptoms, and emotions in family caregivers of ICU patients before and during the COVID-19 pandemic, and to explore families' perceptions and suggestions for the visitation. Methods: A cross-sectional descriptive survey was conducted in 99 family caregivers of adult surgical ICU patients from an urban academic medical center in South Korea (February to July 2021). The WHO's Quality of Life-BREF, Center for Epidemiologic Studies Depression, and Visual Analogue Scale were used to assess quality of life, depressive symptoms, and emotions, respectively. The Family Perception Checklist was used to assess families' perceptions and suggestions about the visitation restriction. Results were compared with the data from our previous survey (n = 187) in 2017. Results: Family caregivers were mostly women (n = 59), adult children (n = 43) or spouse (n = 38) of patients with mean age of 47.34 years. Family caregivers surveyed during the pandemic reported worsening sadness (54.66 ± 28.93, 45.58 ± 29.44, P = 0.005) and anxiety (53.86 ± 30.07, 43.22 ± 29.02, P = 0.001) than those who were surveyed in. While majority of families were satisfied with the visitation restrictions (86.9%), only 50.5% were satisfied with the amount of information provided on the patient's condition. Conclusions: Visitation restriction is necessary during the COVID-19 pandemic despite sadness and anxiety reported in caregivers. Hence, alternative visitation strategies are needed to mitigate psychological distress and provide sufficient information to ICU family caregivers.ope