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Bi-level high flow system (Bi-flow) : An exploratory clinical trial for healthy subjects and hypoxemic respiratory failure patients
No full textBackground: High-flow nasal cannula (HFNC) devices are widely used for oxygen supplementation. However, it supplies the same flow rate during inspiration and expiration, causing turbulence and increased respiratory resistance in the nasopharynx during expiration, leading to patient discomfort. We developed a bi-level high-flow system (Bi-flow) to improve this problem, providing additional flow during inspiration. Objective: We investigated the physiologic effects of applying Bi-flow in healthy individuals and patients with hypoxemic respiratory failure and compared it with conventional HFNC (Uniflow) usage. Methods: For healthy individuals, Uniflow (U30, U40, U50) and Bi-flow (basal flow 10, 20, 30L/min) modes were randomly assigned. Each mode varied the [inspiration/expiration rate] by increasing additional flow during inspiration, as follows: 30/10, 30/20, 40/10, 40/20, 40/30, 50/20, 50/30 trials. Physiologic data (respiratory rate, heart rate, transcutaneous CO2, modified Borg scale) and lung volume (monitored through Electrical Impedance Tomography-EIT) were recorded. Nasal pressure- time product (N-PTP) was calculated as a surrogate marker for work of breathing (WOB). In the hypoxemic patient’s study, Uniflow and Bi-flow modes (BF25, BF50, BF75) were randomly allocated. Bi-flow mode maintained the same inspiratory flow as Uniflow, but supplied a portion of the total flow as additional flow (in percentage). The four modes were compared by analyzing patients’ ROX index (the ratio of oxygen saturation as measured by pulse oximetry/FiO2 to respiratory rate), lung volume, and N-PTP. Results: The healthy individual’s study included twelve healthy individuals. When Bi-flow was applied, a reduction in respiratory rates was observed compared with natural breathing. Additionally, a decrease in inspiratory and expiration N-PTP was noted with Bi-flow. For the 24 patients with hypoxic respiratory failure, there were no significant differences in the ROX index (UF: BF25: BF50: BF75; 13.2: 13.7: 13.4 13.9; p=0.98). However, there was a slight decrease in inspiratory N-PTP in the Bi- flow modes (UF: BF25: BF50: BF75; 11.2: 8.4: 6.0: 9.9; p=0.03). Lung volume data monitored through EIT did not show any significant statistical differences. Conclusion: We applied Bi-flow to healthy individuals and patients with hypoxemic respiratory failure, and the results showed a partial decrease in N-PTP, a proxy of work of breathing. Furthermore, no significant adverse effects were observed. (KCT0006100, KCT0007352)Docto
Factors Affecting Delay to Independent Walking in Liver Transplant Recipients Undergoing Rehabilitation Treatment
No full text본 연구는 단일 기관의 후향적 연구로, 재활 치료를 받은 간이식 수혜자의 독 립 보행 지연에 영향을 주는 요인을 파악하기 위해 시행되었다. 재활 치료를 받 은 간이식 수혜자 157명을 대상으로 하였으며, 재활 종료 시점에서 독립 보행군 과 독립 보행 지연군으로 나누었다. 수집된 자료는 SPSS Statistics for Windows, Version 27.0으로 분석하였고 기술통계, independent t-test, χ2 test 또는 Fisher’s exact test, 로지스틱 회귀분석을 이용하였다. 신경근골격계 이상이 있는 경우(odds ratio [OR]=14.820, 95% confidence interval [CI]=5.057-43.429), 수술 후 재활시작기간(OR=1.038, 95% CI=1.001- 1.076), 재활 시작 평가에서 ERP 4단계인 경우(OR=0.107, 95% CI=0.025-0.455), 재활 시작 평가에서 악력이 5kg 미만인 경우(OR=7.806, 95% CI=2.774-21.961)가 재활 치료를 받은 간이식 수혜자의 독립 보행에 영향을 주는 요인으로 나타났다. 본 연구를 통해 재활 치료를 받은 간이식 수혜자의 독립 보행에 영향을 주는 요인을 확인 할 수 있었다. 연구 결과를 바탕으로 간이식 환자의 수술 후 재활 과정에서 독립 보행 지연을 예방하기 위한 재활 간호 중재를 계획하고 적용할 수 있을 것으로 기대된다. 주요어(Key words): 간이식, 수혜자, 재활, 독립 보행, 영향 요인Maste
Effect of Topical Programmed Death-Ligand1 on Corneal Epithelium in Dry Eye Mouse
No full textDry eye disease (DED) is a growing health concern that impacts millions of individuals every year, and is associated with corneal injury, excessive oxidative stress and inflammation. Current therapeutic strategies, including artificial tears and anti-inflammatory agents, are unable to achieve a permanent clinical cure due to their temporary nature or adverse side effects. Therefore, here, we investigated the effectiveness of the topical administration of programmed death-ligand 1 (PD-L1) in the mouse model of DED. The model was generated in C57BL/6 mice by excising the extra orbital lacrimal gland and causing desiccation stress with scopolamine injections. Subsequently, either phosphate-buffered saline (3 µL/eye) or PD-L1 (0.5 µg/mL) was topically administered for 10 days. Tear volume was evaluated with phenol red thread, and corneal fluorescein staining was observed to quantify the corneal epithelial defect. Corneas were collected for histological analysis, and the expression levels of inflammatory signaling proteins such as CD4, CD3e, IL-17, IL-1β, pIkB-α, pNF-kB and pERK1/2 were assessed through immunofluorescence and Western blot techniques. Our results demonstrate that desiccating stress-induced corneal epithelial defect and tear secretion were significantly improved by topical PD-L1 and could reduce corneal CD4+ T cell infiltration, inflammation and apoptosis in a DED mouse model by downregulating IL-17 production and ERK1/2-NFkB pathways
The Diagnostic Role of Repeated Biopsy of Thyroid Nodules with Atypia of Undetermined Significance with Architectural Atypia on Core-Needle Biopsy
No full textBackground We aimed to evaluate the utility of repeat biopsy of thyroid nodules classified as atypia of undetermined significance with architectural atypia (IIIB) on core-needle biopsy (CNB).
Methods This retrospective study evaluated patients with thyroid nodules categorized as IIIB on CNB between 2013 and 2015. Demographic characteristics, subsequent biopsy results, and ultrasound (US) images were evaluated. The malignancy rates of nodules according to number of CNBs and the number of IIIB diagnoses was compared. Demographic and US features were evaluated to determine factors predictive of malignancy.
Results Of 1,003 IIIB nodules on CNB, the final diagnosis was determined for 328 (32.7%) nodules, with 121 of them confirmed as malignant, resulting in a malignancy rate of 36.9% (95% confidence interval, 31.7% to 42.1%). Repeat CNB was performed in 248 nodules (24.7%), with 75 (30.2%), 131 (52.8%), 13 (5.2%), 26 (10.5%), one (0.4%), and two (0.8%) reclassified into categories II, IIIB, IIIA, IV, V, and VI, respectively. Malignancy rates were not significantly affected by the number of CNBs (P=0.291) or the number of IIIB diagnoses (P=0.473). None of the nodules confirmed as category II on repeat CNB was malignant. US features significantly associated with malignancy (P<0.003) included solid composition, irregular margins, microcalcifications, and high suspicion on the US risk stratification system.
Conclusion Repeat biopsy of nodules diagnosed with IIIB on CNB did not increase the detection of malignancy but can potentially reduce unnecessary surgery. Repeat biopsy should be performed selectively, with US features guiding the choice between repeat biopsy and diagnostic surgery
Impact of the suprapapillary method on patency in distal malignant biliary obstruction: a multicenter randomized controlled trial
No full textBackground and aims: Placement of a self-expandable metal stent (SEMS) across the duodenal major papilla carries a risk of duodenobiliary reflux (DBR). The suprapapillary method of stent placement may reduce DBR and improve stent patency compared with the transpapillary method. This study compared the clinical outcomes between the suprapapillary and transpapillary methods for distal malignant biliary obstruction (DMBO).
Methods: Between January 2021 and January 2023, consecutive patients with DMBO from 6 centers in South Korea were randomly assigned to either the suprapapillary arm or transpapillary method arm in a 1:1 ratio. The primary outcome was the duration of stent patency, and secondary outcomes were the cause of stent dysfunction, adverse events, and overall survival rate.
Results: Eighty-four patients were equally assigned to each group. The most common cause of DMBO was pancreatic cancer (50, 59.5%), followed by bile duct (20, 23.8%), gallbladder (11, 13.1%), and other cancers (3, 3.6%). Stent patency was significantly longer in the suprapapillary group (median, 369 days [interquartile range, 289-497] vs 154 days [interquartile range, 78-361]; P < .01). Development of DBR was significantly lower in the suprapapillary group (9.4% vs 40.8%, P < .01). Adverse events and overall survival rate were not significantly different between the 2 groups.
Conclusions: The placement of SEMSs using the suprapapillary method resulted in a significantly longer duration of stent patency. It is advisable to place the SEMS using the suprapapillary method in DMBO. Further studies with a larger number of patients are required to validate the benefits of the suprapapillary method. (Clinical trial registration number: KCT0005572.)
A novel scoring system to predict short-term mortality after living donor liver transplantation for acute liver failure
No full textLiver transplantation is often the only lifesaving option for acute liver failure (ALF); however, the predictors of short-term mortality (death within one year) after living donor liver transplantation (LDLT) for ALF have yet to be defined. We retrospectively collected patients ≥18years old who underwent LDLT for ALF between 2010 and 2020 at 35 centers in Asia. Univariate and multivariate logistic regression analyses were conducted to identify the clinical variables related to short-term mortality and establish a novel scoring system. The Kaplan Meier method was performed to explore the association between the score and overall survival. Of the 339 recipients, 46 (13.6%) died within 1 year after LDLT. Multivariate analyses revealed 4 independent risk factors for death: use of vasopressors or mechanical ventilation, the higher model for end-stage liver disease score, and a lower graft-to-recipient weight ratio. The internally validated c-statistic of the short-term mortality after transplant (SMT) score derived from these 4 variables was 0.80 (95% confidence interval: 0.74-0.87). The SMT score successfully stratified recipients into low-, intermediate-, and high-risk groups with 1-year overall survival rates of 96%, 80%, and 50%, respectively. In conclusion, our novel SMT score based on 4 predictors will guide ALF recipient and living donor selection
Programming Anisotropic Functionality of 3D Microdenticles by Staggered-Overlapped and Multilayered Microarchitectures
No full textNatural sharkskin features staggered-overlapped and multilayered architectures of riblet-textured anisotropic microdenticles, exhibiting drag reduction and providing a flexible yet strong armor. However, the artificial fabrication of three-dimensional (3D) sharkskin with these unique functionalities and mechanical integrity is a challenge using conventional techniques. In this study, it is reported on the facile microfabrication of multilayered 3D sharkskin through the magnetic actuation of polymeric composites and subsequent chemical shape fixation by casting thin polymeric films. The fabricated hydrophobic sharkskin, with geometric symmetry breaking, achieves anisotropic drag reduction in frontal and backward flow directions against the riblet-textured microdenticles. For mechanical integrity, hard-on-soft multilayered mechanical properties are realized by coating the polymeric sharkskin with thin layers of zinc oxide and platinum, which have higher hardness and recovery behaviors than the polymer. This multilayered hard-on-soft sharkskin exhibits friction anisotropy, mechanical robustness, and structural recovery. Furthermore, coating the MXene nanosheets provides the fabricated sharkskin with a low electrical resistance of ≈5.3 Ω, which leads to high Joule heating (≈229.9 °C at 2.75 V). The proposed magnetomechanical actuation-assisted microfabrication strategy is expected to facilitate the development of devices requiring multifunctional microtextures
Incidence and outcomes of delayed intracranial hemorrhage: a population-based cohort study
No full textHead trauma is a common reason for emergency department (ED) visits. Delayed intracranial hemorrhage (ICH) in patients with minor head trauma is a major concern, but controversies exist regarding the incidence of delayed ICH and discharge planning at the ED. This study aimed to determine the incidence of delayed ICH in adults who developed ICH after a negative initial brain computed tomography (CT) at the ED and investigate the clinical outcomes for delayed ICH. This nationwide population cohort study used data from the National Health Insurance Service of Korea from 2013 to 2019. Adult patients who presented to an ED due to trauma and were discharged after a negative brain CT examination were selected. The main outcomes were the incidence of ICH within 14 days after a negative brain CT at initial ED visit and the clinical outcomes of patients with and without delayed ICH. The study patients were followed up to 1 year after the initial ED discharge. Cox proportional hazard regression analysis was used to estimate the hazard ratio for all-cause 1-year mortality of delayed ICH. During the 7-year study period, we identified 626,695 adult patients aged 20 years or older who underwent brain CT at the ED due to minor head trauma, and 2666 (0.4%) were diagnosed with delayed ICH within 14 days after the first visit. Approximately two-thirds of patients (64.3%) were diagnosed with delayed ICH within 3 days, and 84.5% were diagnosed within 7 days. Among the patients with delayed ICH, 71 (2.7%) underwent neurosurgical intervention. After adjustment for age, sex, Charlson Comorbidity Index, and insurance type, delayed ICH (adjusted hazard ratio, 2.15; 95% confidence interval, 1.86-2.48; p < 0.001) was significantly associated with 1-year mortality. The incidence of delayed ICH was 0.4% in the general population, with the majority diagnosed within 7 days. These findings suggest that patient discharge education for close observation for a week may be a feasible strategy for the general population
Management of atypical femoral fracture nonunion using nail exchange with augmentative plate
No full text배경
비정형 대퇴골 골절 수술 후 발생한 불유합은 치료가 어려우며 이에 대한 연구 또한 제한적인 상태이다. 본 연구의 목표는 비정형 대퇴골 골절 불유합 치료에서 골수내정 교체와 보강 금속판을 이용한 수술의 결과를 조사하여 효과적인 치료 방침을 세우는 것이다.
방법
2018년 1월부터 2022년 12월까지 단일 기관에서 비정형 대퇴골 골절 불유합에 대해 골수내정 교체와 보강 금속판을 이용하여 치료받은 10명의 여성 환자를 대상으로 후향적 분석을 수행하였다. 골수내정이 부러졌거나 5도 이상의 내반 변형이 있을 경우 골수내정 교체를 시행하였고, X-ray 상 임플란트 주변의 해리 징후가 관찰되어 기계적 불안정성이 의심되는 경우 금속판 보강을 시행하였다. 골 리모델링 억제 정도를 확인하기 위해 수술 전 골대사 표지자를 측정했으며, 수술 시에는 골절 정복, 튼튼한 고정에 중점을 두었고, 생물학적 손상 해결을 위해 뼈 이식을 하였다. 주요 결과지표로 금속판 고정력 확인을 위한 나사가 관통한 피질골 수, 부정 정렬 교정 여부 확인을 위한 수술 전후 경부-골간 각도(Neck-shaft angle, NSA) 차이, 수술 전후 보행 기능의 개선 정도를 파악하기 위한 Koval 점수를 측정하였다.
결과
평균 21.4±7.4주 이내에 이러한 수술 방법을 통하여 10명의 환자 모두에서 성공적으로 골유합을 달성하였다. 모든 사례에서 기계적 불안정성 문제를 나타내는 해리 징후가 관찰되었다. 보강 금속판을 통해 근위 및 원위 골편에서 각각 평균 4.8±3.2 및 4.6±2.5 피질골을 고정하여 기계적 안정성을 향상시켰다. 내반 부정정렬이 있던 여섯 명의 환자에서 수술 후 경부-골간 각도가 건측에 맞게 성공적으로 교정되었다. 또한, 대부분의 비스포스포네이트 또는 데노수맙을 사용하지 않은 환자에서 수술 전 골대사표지자가 정상화되어, 장기간의 항흡수 치료로 인한 골 리모델링 억제가 수술 전에 회복될 수 있음을 시사했다. Koval 점수는 수술 전 평균 4.2에서 수술 1년 후 1.6으로 감소하여 보행 능력의 상당한 회복을 나타냈다.
결론
부정정렬 교정을 위한 골수내정의 교체와 강력한 고정을 위한 보강 금속판 사용은 비정형 대퇴골 골절 수술 후 불유합 치료에 매우 효과적임을 입증하였고, 이러한 복잡한 사례에 대한 주요 치료 방법으로서 잠재력을 보여주었다.|Background
Management of nonunion in atypical femoral fractures (AFF) poses significant challenges. This study investigates the outcomes of nail exchange and augmentative plating in treating AFF nonunion, aiming to define effective management strategies.
Methods
A retrospective analysis was conducted on 10 female patients treated for AFF nonunion with nail exchange and augmentative plating at a single center from January 2018 to December 2022. Criteria for exchange nailing included broken nails or varus malreduction > 5 degrees, while augmentative plating targeted cases with mechanical instability shown by peri-implant X-ray loosening signs. Preoperative bone turnover markers (BTMs) were evaluated to measure bone remodeling suppression, with surgical techniques focusing on fracture reduction, fixation stability, and addressing biological impairment. The effectiveness of screw fixation in plating measured by the number of cortices purchased by the screw, malalignment correction via neck-shaft angle (NSA) adjustments, and improvements in ambulatory function using the Koval score were key outcome measures.
Results
The combined surgical approach demonstrated significant success, achieving bone union in all 10 patients within an average timeframe of 21.4± 7.4 weeks. A notable observation across all cases was the prevalence of loosening signs, indicative of the mechanical instability challenges inherent in AFF nonunion. Mechanical stability was enhanced by securing an average of 4.8±3.2 and 4.6±2.5 cortices in proximal and distal fragments, respectively, through augmentative plating. Among the cases, six exhibited varus malalignment which was successfully corrected, bringing postoperative NSA in line with the contralateral side. Additionally, the analysis revealed that in most patients not using bisphosphonate or denosumab, preoperative BTMs were normalized, suggesting that suppression of bone remodeling, a concern with long-term antiresorptive therapy, could be recovered prior to surgery. The Koval score decreased from an average of 4.2 preoperatively to 1.6 one year post-surgery, indicating a considerable recovery in walking ability.
Conclusion
Correcting malalignment and employing augmentative plating for rigid fixation proved highly effective in treating AFF nonunion, achieving notable success in bone union. This strategy is critical for managing complex cases, showcasing its potential as a key treatment modality.Maste
손목터널증후군 발생 위험 인자가 손목터널증후군 치료 방법에 미치는 영향: 스테로이드 주사 치료와 수술적 치료를 중심으로
No full textSeveral studies have revealed the risk factors for carpal tunnel syndrome (CTS). However, no studies have evaluated the influence of these risk factors on the selection of treatment modalities for CTS. This study aimed to determine the influence of CTS risk factors on the selection of CTS treatment modalities with a focus on corticosteroid injection (CI) and surgery. We conducted a retrospective cohort study of patients aged ≥20 years with newly diagnosed CTS in the Korean health insurance review and assessment service between 2010 and 2019. We evaluated the demographic information, the existence of CTS risk factors, and the applied treatment modalities for CTS, including CI and operation. The CTS risk factors include age, sex, diabetes mellitus, osteoarthritis of the hand or wrist, rheumatoid arthritis, hypothyroidism, gout, chronic kidney disease (CKD) on dialysis, antiestrogen or aromatase inhibitor medication, and a history of distal radius fracture (DRF). Multivariable logistic regression analyses were conducted. Age over 80 years was the most significantly associated factor for the selection of CI in CTS (odd ratio [OR], 2.149; 95% confidence interval [CI], 2.092 to 2.209; P < .001). Among underlying diseases or medications, CKD on dialysis (OR, 4.001; 95% CI, 3.819-4.193; P < .001) was the most significant associated factor for the selection of operation for CTS, followed by a history of DRF (OR, 1.803; 95% CI, 1.749-1.860; P < .001). Old age was the most significantly related factor for selecting CI. Among underlying diseases or medications, CKD on dialysis and the history of DRF were the most significantly related factors for selecting operative treatment. For these patients, clinicians should proactively consider an operation to reduce the long-term discomfort and economic burdens