Early thrombus detection in the extracorporeal membrane oxygenation circuit by noninvasive real-time ultrasonic sensors.

Thrombus formation in extracorporeal membrane oxygenation (ECMO) remains a major concern as it can lead to fatal outcomes. To the best of our knowledge, there is no standard non-invasive method for quantitatively measuring thrombi. This study's purpose was to verify thrombus detection in an ECMO circuit using novel, non-invasive ultrasonic sensors in real-time, utilizing the fact that the ultrasonic velocity in a thrombus is known to be higher than that in the blood. Ultrasonic sensors with a customized chamber, an ultrasonic pulse-receiver, and a digital storage oscilloscope (DSO) were used to set up the measuring unit. The customized chamber was connected to an ECMO circuit primed with porcine blood. Thrombi formed from static porcine blood were placed in the circuit and ultrasonic signals were extracted from the oscilloscope at various ECMO flow rates of 1-4 L/min. The ultrasonic signal changes were successfully detected at each flow rate on the DSO. The ultrasonic pulse signal shifted leftward when a thrombus passed between the two ultrasonic sensors and was easily detected on the DSO screen. This novel real-time non-invasive thrombus detection method may enable the early detection of floating thrombi in the ECMO system and early management of ECMO thrombi.

Clinical implication of intraoperative ventricular-arterial coupling in pediatric patients undergoing ventricular septal defects repair: A retrospective cohort study.

BACKGROUND: Ventricular-arterial coupling is the ratio of arterial elastance to ventricular end-systolic elastance. AIMS: The objective of this study was to determine the clinical implication of intraoperative ventricular-arterial coupling derived from the pressure-area relationship using transesophageal echocardiography. METHODS: This retrospective study reviewed the medical records of 72 pediatric patients with ventricular septal defects who underwent corrective surgery with cardiopulmonary bypass. The single-beat modified method was used to assess ventricular-arterial coupling. Logistic regression analyses were performed to determine the correlation between ventricular-arterial coupling and early postoperative outcomes, including the maximum vasoactive-inotropic score, length of mechanical ventilation, and length of hospital stay. RESULTS: Ventricular-arterial coupling after cardiopulmonary bypass significantly increased (from 1.0 ± 0.4 to 1.4 ± 0.8, p < .001), indicating a disproportionate increase in the arterial elastance index (from 11.5 ± 5.1 to 19.8 ± 7.5 mmHg/cm2 /m2 , p < .001) compared with the ventricular end-systolic elastance index (from 13.0 ± 6.9 to 16.9 ± 9.0 mmHg/cm2 /m2 , p < .001). Logistic regression analyses revealed that high postoperative ventricular-arterial coupling was independently associated with higher postoperative maximum vasoactive-inotropic score (>10; odds ratio [OR], 8.04; 95% confidence interval [CI], 1.38-46.85, p = .020), longer postoperative mechanical ventilation (>15 h; OR: 11.00; 95% CI: 1.26-96.45, p = .030), and longer postoperative hospital stay (>7 days; OR: 2.98; 95% CI: 1.04-8.58, p = .043). CONCLUSIONS: Ventricular-arterial coupling can be easily obtained from the intraoperative transesophageal echocardiography in pediatric patients undergoing ventricular septal defects repair. High postoperative ventricular-arterial coupling is strongly associated with worse early postoperative outcomes. Ventricular-arterial coupling shows promise as an intraoperative analysis tool that can provide insight into the impact of interventions on cardiovascular performance and identify potential targets for treatment in this population.

Use of a High-Flow Nasal Cannula in a Child With a Functional Single Ventricle and Difficult Airway.

Inducing anesthesia and securing the airway without disrupting the patient's hemodynamic state are challenging in pediatric patients with a functional single ventricle (FSV). Here, the authors report effective use of a high-flow nasal cannula (HFNC) as a tool in providing oxygen supplementation for airway management in pediatric FSV patients with a history of a difficult airway. A female patient, aged 5 years 7 months, was admitted for extracardiac conduit Fontan procedure. The patient had a history of multiple failed attempts at endotracheal intubation and was diagnosed with retrognathia and severe oral trismus of less than 1 finger width. The patient had another event of mask ventilation failure after propofol sedation during the preoperative computed tomography scan a day before the surgery. The patient's preoperative cardiac catheterization report revealed that the Qp/Qs ratio of 0.82 at room air, and the patient's peripheral oxygen saturation (SpO2) ranged from 70% to 80% at room air. On entering the operating room, the preoxygenation process began with HFNC at an oxygen flow of 16 L/min, with a fraction of inspired oxygen (FIO2) set at 95% after light sedation with an intravenous bolus of midazolam, 0.1 mg/kg. After 4 minutes of applying HFNC, with SpO2 rising from 76% to 98%, anesthetic medications were administered intravenously without a neuromuscular blocking agent to preserve spontaneous breathing. The patient was not ventilated with a facemask but instead left with HFNC in place for continuous supplemental oxygenation. The patient's airway was secured in a single attempt in 80 seconds. HFNC is an ideal option for oxygen supplementation during airway management of pediatric FSV patients, as their balance of pulmonary and systemic flow is perturbed easily by subtle physiologic alteration and therapeutic maneuvers during the induction of general anesthesia and highly susceptible to rapid desaturation and cardiovascular collapse, and should be considered as having a physiologically difficult airway.

Delineation of high resolution climate regions over the Korean Peninsula using machine learning approaches.

In this research, climate classification maps over the Korean Peninsula at 1 km resolution were generated using the satellite-based climatic variables of monthly temperature and precipitation based on machine learning approaches. Random forest (RF), artificial neural networks (ANN), k-nearest neighbor (KNN), logistic regression (LR), and support vector machines (SVM) were used to develop models. Training and validation of these models were conducted using in-situ observations from the Korea Meteorological Administration (KMA) from 2001 to 2016. The rule of the traditional Köppen-Geiger (K-G) climate classification was used to classify climate regions. The input variables were land surface temperature (LST) of the Moderate Resolution Imaging Spectroradiometer (MODIS), monthly precipitation data from the Tropical Rainfall Measuring Mission (TRMM) 3B43 product, and the Digital Elevation Map (DEM) from the Shuttle Radar Topography Mission (SRTM). The overall accuracy (OA) based on validation data from 2001 to 2016 for all models was high over 95%. DEM and minimum winter temperature were two distinct variables over the study area with particularly high relative importance. ANN produced more realistic spatial distribution of the classified climates despite having a slightly lower OA than the others. The accuracy of the models using high altitudinal in-situ data of the Mountain Meteorology Observation System (MMOS) was also assessed. Although the data length of the MMOS data was relatively short (2013 to 2017), it proved that the snowy, dry and cold winter and cool summer class (Dwc) is widely located in the eastern coastal region of South Korea. Temporal shifting of climate was examined through a comparison of climate maps produced by period: from 1950 to 2000, from 1983 to 2000, and from 2001 to 2013. A shrinking trend of snow classes (D) over the Korean Peninsula was clearly observed from the ANN-based climate classification results. Shifting trends of climate with the decrease/increase of snow (D)/temperate (C) classes were clearly shown in the maps produced using the proposed approaches, consistent with the results from the reanalysis data of the Climatic Research Unit (CRU) and Global Precipitation Climatology Centre (GPCC).

Pretransplant increases in left ventricular volume and mass are associated with QT prolongation during pediatric liver transplantation.

Structural alterations in the cirrhotic heart may contribute to electromechanical abnormalities, represented by QT prolongation. The aim of this study was to investigate the changes in QTc according to the operative stage during pediatric LT and to identify which baseline echocardiographic parameters were associated with intraoperative QTc prolongation. Data were evaluated from 39 children undergoing LT for chronic liver disease (median age 9 months). In 19 patients (48.7%), baseline QTc was prolonged ≥440 ms (462 ± 19 ms). Through the period of post-reperfusion, QTI, QTc, and JTI progressively increased, although values partially recovered toward the end of surgery. High LVMI (≥82.51 g/m2 ) was associated with baseline QTc ≥ 440 ms (OR = 1.034, P = .032). In the 5 minutes post-reperfusion stage, marked QTc prolongation (defined as QTc ≥ 500 ms; n = 24, 61.5%) was significantly associated with high EDVI (OR = 1.060, P = .027) and SVI (OR = 1.075, P = .026). In children with chronic liver disease, increased ventricular volumes and mass may increase the risk of QTc prolongation during LT, suggesting that repolarization abnormalities might be contributed by structural changes characteristic of cirrhotic cardiomyopathy.

Comparison of acute kidney injury between ABO-compatible and ABO-incompatible living donor liver transplantation: A propensity matching analysis.

The anti-CD20 monoclonal antibody rituximab has significantly decreased the prevalence of antibody-mediated rejection of ABO-incompatible (ABOi) living donor liver transplantation (LDLT). However, little is known about acute kidney injury (AKI) following ABOi LDLT. The aim of this study was to identify the incidence of AKI in ABOi LDLT and compare it with that of ABO-compatible (ABOc) LDLT. We retrospectively collected and analyzed the data of 1617 patients who underwent liver transplant surgery from November 2008 to December 2014. Risk factors for AKI were investigated using multivariate regression analysis. In 271 ABOi LDLTs, AKI occurred in 184 (67.9%) according to Kidney Disease: Improving Global Outcomes criteria. After propensity score matching, the incidence of AKI was significantly higher after ABOi LDLT than after ABOc LDLT (67.0% versus 48.2%; P < 0.001). Furthermore, the intensive care unit stay (P = 0.01) was significantly prolonged, but there were no significant differences in mortality (P = 0.74), graft failure (P = 0.32), and postoperative dialysis (P = 0.74) between the 2 groups. Hemoglobin level and operation time were independent risk factors for AKI following ABOi LDLT. In conclusion, the incidence of AKI is higher in ABOi LDLT than ABOc LDLT. However, the impact of AKI on postoperative outcomes was not marked in our study. Therefore, ABOi LDLT in selected patients is promising with apparent good graft and survival outcomes. Liver Transplantation 22 1656-1665 2016 AASLD.

Clinical Validation of Anyplex II HPV HR Detection Test for Cervical Cancer Screening in Korea.

CONTEXT: The Anyplex II HPV HR detection kit (Seegene Inc, Seoul, Korea) is a new, multiplex, real-time polymerase chain reaction assay to detect individual 14 high-risk (HR) human papillomavirus (HPV) types in a single tube. OBJECTIVE: To evaluate the clinical performance of the HPV HR kit in predicting high-grade squamous intraepithelial lesions and cervical intraepithelial lesions grade 2 or worse in cervical cancer screening. DESIGN: We analyzed 1137 cervical samples in Huro Path medium (CelltraZone, Seoul, Korea) from Korean women. The clinical performance of the HPV HR kit was compared with Hybrid Capture 2 (Qiagen, Valencia, California) using the noninferiority score test in a routine cervical cancer screening setting. The intralaboratory and interlaboratory agreements of HPV HR were also evaluated. RESULTS: Overall agreement between the 2 assays was 92.4% (1051 of 1137) with a κ value of 0.787. Clinical sensitivity of HPV HR for high-grade squamous intraepithelial lesions and cervical intraepithelial lesions grade 2 or worse was 94.4% (95% confidence interval [CI], 89.2-99.7) and 92.5% (95% CI, 84.3-100.0), respectively. The respective values for Hybrid Capture 2 were 93.1% (95% CI, 87.2-98.9) and 87.5% (95% CI, 77.3-99.7). Clinical sensitivity and specificity of HPV HR were not inferior to those of Hybrid Capture 2 (P = .005 and P = .04, respectively). The HPV HR showed good intralaboratory and interlaboratory reproducibility at 98.0% (κ = 0.953) and 97.4% (κ = 0.940), respectively. CONCLUSIONS: The HPV HR demonstrates comparable performance to the Hybrid Capture 2 test and can be useful for HPV-based cervical cancer screening testing.

Anaphylactic reactions after cisatracurium administration in two patients -a report of two cases-.

Cisatracurium was initially characterized to have no evident histamine-releasing potential with excellent cardiovascular stability. However, severe anaphylactic reactions to cisatracurium that resulted in bronchospasms and cardiovascular collapse have been reported worldwide. Two cases of severe anaphylactic reactions after the administration of cisatracurium are presented. The anesthetics used in both cases were lidocaine, midazolam, propofol (microemulsion propofol in the second case), remifentanil and cisatracurium. After the administration of these drugs, bronchospasm and hypotension manifested, leading to the diagnosis of anaphylaxis and appropriate treatment. Skin intradermal testing confirmed that both cases were due to immune-mediated anaphylaxis to cisatracurium, despite the fact that neither of the patients had been exposed to the allergen previously. The anaphylaxis may be due to cross-reactivity between neuromuscular blocking agents and substances with quaternary ammonium ions. Anesthesiologists should be aware that cisatracurium has the potential to trigger severe anaphylactic reactions via an immune-mediated mechanism.

Ultra-rapid elimination of biofilms via the combustion of a nanoenergetic coating.

BACKGROUND: Biofilms occur on a wide variety of surfaces including metals, ceramics, glass etc. and often leads to accumulation of large number of various microorganisms on the surfaces. This biofilm growth is highly undesirable in most cases as biofilms can cause degradation of the instruments and its performance along with contamination of the samples being processed in those systems. The current "offline" biofilm removal methods are effective but labor intensive and generates waste streams that are toxic to be directly disposed. We present here a novel process that uses nano-energetic materials to eliminate biofilms in < 1 second. The process involves spray-coating a thin layer of nano-energetic material on top of the biofilm, allowing it to dry, and igniting the dried coating to incinerate the biofilm. RESULTS: The nanoenergetic material is a mixture of aluminum (Al) nanoparticles dispersed in a THV-220A (fluoropolymer oxidizer) matrix. Upon ignition, the Al nanoparticles react with THV-220A exothermically, producing high temperatures (>2500 K) for an extremely brief period (~100 ms) that destroys the biofilm underneath. However, since the total amount of heat produced is low (~0.1 kJ/cm2), the underlying surface remains undamaged. Surfaces with biofilms of Pseudomonas aeruginosa initially harboring ~ 10(7) CFU of bacteria /cm2 displayed final counts of less than 5 CFU/cm2 after being subjected to our process. The byproducts of the process consist only of washable carbonaceous residue and gases, making this process potentially inexpensive due to low toxic-waste disposal costs. CONCLUSIONS: This novel method of biofilm removal is currently in the early stage of development. However, it has potential to be used in offline biofilm elimination as a rapid, easy and environmentally friendly method.

Rapid identification of spontaneously resolving capnothorax using bedside M-mode ultrasonography during laparoscopic surgery: the "lung point" sign -two cases report-.

Pneumothorax during general anesthesia is more difficult to diagnose compared with that of non-anesthetized patient. Furthermore, the early diagnosis of pneumothorax is to some extent difficult due to CO2-pneumoperitoneum during laparoscopic surgery. The use of ultrasonography to diagnose pneumothorax has increased in a variety of situations, demonstrating a better diagnostic rate than conventional chest radiography. Here, we report two cases of intraoperative capnothorax that were confirmed using the M-mode "lung point" sign. However, the insertion of a chest tube could have been avoided because the spontaneous resolution of capnothorax was quickly identified using bedside lung ultrasonography.

Kinetically limited differential centrifugation as an inexpensive and readily available alternative to centrifugal elutriation.

When separating two species with similar densities but differing sedimentation velocities (because of differences in size), centrifugal elutriation is generally the method of choice. However, a major drawback to this approach is the requirement for specialized equipment. Here, we present a new method that achieves similar separations using standard benchtop centrifuges by loading the seperands as a layer on top of a dense buffer of a specified length, and running the benchtop centrifugation process for a calculated amount of time, thereby ensuring that all faster moving species are collected at the bottom, while all slower moving species remain in the buffer. We demonstrate the use of our procedure to isolate bacteria from blood culture broth (a mixture of bacterial growth media, blood, and bacteria).

Development and in vitro studies of a polyethylene terephthalate-gold nanoparticle scaffold for improved biocompatibility.

Polyethylene terephthalate (PET) mesh is one of the most commonly used synthetic biomaterials for tension-free hernia repair. In an effort to improve the biocompatibility of PET mesh, gold nanoparticles (AuNP) in various concentrations were conjugated to the PET surface to develop PET-AuNP scaffolds. These novel scaffolds were characterized with Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) to assess the addition of functional groups, presence of AuNPs, and thermal stability of the modified PET mesh, respectively. The biocompatibility of the PET-AuNP scaffolds was evaluated through in vitro cell culture assays. The cellularity of cells exposed to the PET-AuNP scaffolds, as well as the scaffolds' ability to reduce reactive oxygen species, was assessed using L929 murine fibroblasts. Antimicrobial properties of AuNPs conjugated to PET mesh were tested against the bacteria Pseudomonas aeruginosa. Results from the FT-IR showed presence of COOH groups while SEM displayed bonding of AuNPs to the PET surface. DSC results indicated that the PET more than likely did not undergo any detrimental degradation due to the surface modification. Results from the in vitro studies showed that AuNPs, in optimal concentrations (1× concentrations), enhanced cellularity, reduced ROS, and reduced bacteria adhesion to PET. These studies demonstrated enhanced biocompatibility of the AuNP conjugated PET mesh over pristine PET mesh.

Kenojeinin I, antimicrobial peptide isolated from the skin of the fermented skate, Raja kenojei.

An antimicrobial peptide was purified from fermented skate skin extract using the solid-phase extraction and separation on HPLC reversed-phase chromatography. Amino acid sequence of the purified peptide (Peak A) having an antimicrobial activity revealed the presence of many cationic residues of the total 28 amino acids. Its molecular mass was found to be 3059 Da. This result was in excellent agreement with the theoretical molecular mass calculated from the amino acid sequence. The synthetic kenojeinin I had inhibitory effects on B. subtilis (MIC, 12 microg/ml), E. coli (28 microg/ml), and S. cerevisiae (12 microg/ml). These results indicate that fermented skate skin is potentially antimicrobial.