Choice Of Fluid Research Articles

Fluid management of acute kidney injury.

Acute kidney injury (AKI) is commonly encountered in critical care medicine as is intravenous fluid therapy. It is accepted that there is interplay between fluid use and AKI, both potentially positive and negative. An understanding of the physiological rationale for fluid is important to help clinicians when considering fluid therapy in patients with, or at risk for AKI; this includes understanding choice of fluid, method of monitoring, administration and clinical sequelae. There is increasing interest in combining both static and dynamic measures to assess fluid balance, fluid responsiveness effects of fluid therapy, which are areas requiring ongoing study to translate this theory into clinically useful practice at the bedside. Whilst the debate of choice of crystalloid in ICU practice continues, further evidence for benefits for balanced solutions emerges in the form of international guidelines and patient data meta-analysis of previously performed trials. This review assesses the physiological rationale for fluid use in ICU cohorts with AKI of various types, as well as a systematic approach for choice of fluid therapy using a number of different variables, which aims to help guide clinicians in managing fluid use and fluid balance in critically ill patients with AKI.

Influence of Process Liquids on the Formation of Strengthened Nanocrystalline Structures in Surface Layers of Steel Parts during Thermo-Deformation Treatment

The results of the influence of a range of process liquids on the formation of strengthened nanocrystalline structures in the surface layers of steel samples with different carbon content during thermo-deformation treatment are presented. The liquids were mineral oil; mineral oil with active additives containing polymers; water; and an aqueous solution of mineral salts based on magnesium and calcium chlorides. The thickness and hardness of the nanocrystalline layer increased with increasing steel carbon content. The thickness and microhardness of Steel C45 are 230–240 μm and 8.6 GPa, respectively, when using mineral oil with AAP, 110–120 μm and 7.2 GPa, respectively, when using mineral oil alone, and for steel CT80 when using mineral oil, they are 180–200 μm and 9.1 GPa, respectively (C45 and CT80 refers to engineering steels). The process liquid is decomposed into its component chemical elements by the high temperatures and pressures in the contact zone of the tool with the treated surface. It also gives off active hydrogen, which diffuses into the surface layer of the metal and significantly affects its formation. It was established that the greatest thickness and hardness of the layers were obtained after processing pre-hydrogenated samples. The choice of process fluid is critical during thermo-deformation treatment.

“To BAL or not to BAL, that is the question”: Variations in smoke inhalation injury guidelines from burn units and centres in England, Scotland and Wales

AimTo evaluate variations in diagnostic criteria and management recommendations for smoke inhalation injury (SII) amongst the burn networks of England, Scotland, and Wales. MethodsA descriptive cross-sectional study examining SII guidelines provided by adult burn units and centres in England, Scotland and Wales. ResultsAll 16 adult burn units and centres responded. Fourteen (87.5 %) had guidelines. Due to sharing of guidelines, ten unique guidelines were assessed. Diagnostic criteria showed variability with no universal criterion shared amongst guidelines. Bronchoscopy was recommended by 90 % of guidelines, but the timing varied. The use of bronchoscopic scoring systems was recommended by four guidelines. Bronchoalveolar lavage (BAL) was recommended by four, with considerable variation in frequency and choice of lavage fluid. All guidelines advised at least one nebulised agent: heparin (n = 8); N-acetyl cysteine (NAC) (n = 8); or salbutamol (n = 8). All guidelines included advice on carbon monoxide poisoning; however, carboxyhaemoglobin (COHb) cut-off levels for treatment varied (5 % [n-4], 10 % [n = 3], 15 % [n = 1]). All recommended high-flow oxygen. Seven (70 %) guidelines offered guidance on cyanide poisoning. Reduced/altered consciousness was the only consistent diagnostic criterion. Five (50 %) guidelines provided intubation guidance, emphasising the role of a ‘senior clinician’ as the intubator. Ventilatory guidance appeared in eight guidelines, focusing on lung protective ventilation (n = 8); oxygenation goals (n = 3); and permissive hypercapnia (n = 3). Within lung-protective ventilation, advice on tidal volume (6, or 6–8 ml/kg) and plateau pressures (>30 cmH2O) were presented most commonly (n = 7). ConclusionThis study has outlined the substantial variations in guidance for the management of SII. The results underscore the need for a national guideline outlining a standardised approach to the diagnosis and management of SII, within the limitations of the current evidence.

Extracellular Vesicle miRNAs in Diagnostics of Gastric Cancer.

Gastric cancer (GC) poses a significant global health challenge because of its high mortality rate attributed to the late-stage diagnosis and lack of early symptoms. Early cancer diagnostics is crucial for improving the survival rates in GC patients, which emphasizes the importance of identifying GC markers for liquid biopsy. The review discusses a potential use of extracellular vesicle microRNAs (EV miRNAs) as biomarkers for the diagnostics and prognostics of GC. Methods. Original articles on the identification of EV miRNA as GC markers published in the Web of Science and Scopus indexed issues were selected from the PubMed and Google Scholar databases. We focused on the methodological aspects of EV analysis, including the choice of body fluid, methods for EV isolation and validation, and approaches for EV miRNA analysis. Conclusions. Out of 33 found articles, themajority of authors investigated blood-derived extracellular vesicles (EVs); only a few utilized EVs from other body fluids, including tissue-specific local biofluids (washing the tumor growth areas), which may be a promising source of EVs in the context of cancer diagnostics. GC-associated miRNAs identified in different studies using different methods of EV isolation and analysis varied considerably. However, three miRNAs (miR-10b, miR-21, and miR-92a) have been found in several independent studies and shown to be associated with GC in experimental models. Further studies are needed to determine the optimal miRNA marker panel. Another essential step necessary to improve the reliability and reproducibility of EV-based diagnostics is standardization of methodologies for EV handling and analysis of EV miRNA.

European Society of Intensive Care Medicine clinical practice guideline on fluid therapy in adult critically ill patients. Part 1: the choice of resuscitation fluids.

This is the first of three parts of the clinical practice guideline from the European Society of Intensive Care Medicine (ESICM) on resuscitation fluids in adult critically ill patients. This part addresses fluid choice and the other two will separately address fluid amount and fluid removal. This guideline was formulated by an international panel of clinical experts and methodologists. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was applied to evaluate the certainty of evidence and to move from evidence to decision. For volume expansion, the guideline provides conditional recommendations for using crystalloids rather than albumin in critically ill patients in general (moderate certainty of evidence), in patients with sepsis (moderate certainty of evidence), in patients with acute respiratory failure (very low certainty of evidence) and in patients in the perioperative period and patients at risk for bleeding (very low certainty of evidence). There is a conditional recommendation for using isotonic saline rather than albumin in patients with traumatic brain injury (very low certainty of evidence). There is a conditional recommendation for using albumin rather than crystalloids in patients with cirrhosis (very low certainty of evidence). The guideline provides conditional recommendations for using balanced crystalloids rather than isotonic saline in critically ill patients in general (low certainty of evidence), in patients with sepsis (low certainty of evidence) and in patients with kidney injury (very low certainty of evidence). There is a conditional recommendation for using isotonic saline rather than balanced crystalloids in patients with traumatic brain injury (very low certainty of evidence). There is a conditional recommendation for using isotonic crystalloids rather than small-volume hypertonic crystalloidsin critically ill patients in general (very low certainty of evidence). This guideline provides eleven recommendations to inform clinicians on resuscitation fluid choice in critically ill patients.

The effect of adding hybrid nanoparticles (Al2O3–TiO2) on the performance of parabolic trough solar collectors using different thermal oils and molten salts

Enhancing the operational efficiency of parabolic trough solar collector (PTSC) systems is key to the advancement of solar energy technologies that enhance power generation sustainability. In the quest for efficient, environmentally friendly energy sources, solar energy systems have been a major focus of both researchers and industry. Adding hybrid nanoparticles (Al2O3–TiO2) to different base fluids of thermal oil or molten salts and then simulating the PTSC's energetic and exergetic performance is pivotal to efficiency enhancement. The focus of this paper will be on three thermal oils Syltherm-800, Therminol VP-1, and Therminol 75 that are used as base fluids with the addition of hybrid nanoparticles. Molten salts such as Solar Salt, Hitec, and HitecXL, which are considered different base fluid types, are also simulated with the same hybrid nanoparticle combination. The inlet temperature is found to be a determining factor in the choice of the base fluid. Inlet temperatures in the range of 300–650 K for thermal oils with the addition of Al2O3–TiO2 have improved the thermal and exergy efficiency of the PTSC by approximately 0.99 % and 0.59 %, respectively. Therminol VP-1/Al2O3–TiO2 has the highest average thermal efficiency among other thermal oils, with an average percentage of 71.68 %, while Syltherm-800/Al2O3–TiO2 has recorded the highest exergy efficiency of 24.1 %. At higher inlet temperatures above 500 K mixing Al2O3–TiO2 with molten salts has increased both energetic and exergetic PTSC performance by approximately 0.60 %. Solar Salt/Al2O3–TiO2 has the highest average thermal and exergy efficiency of 61.8 % and 36.1 %, respectively.

Perioperative Dyselectrolytemia in Patients Undergoing Transurethral Resection of the Prostate Using 0.9% Normal Saline Irrigation.

The choice of irrigation fluid used in transurethral resection of the prostate (TURP) has a significant impact on serum electrolyte levels. Among the many available options, 0.9% normal saline (NS) is considered to be more physiological. This observational study was conducted on 60 adult males aged 50-70 years, classified as American Society of Anesthesiologists grade 1 and 2, undergoing TURP with 0.9% NS irrigation under spinal anesthesia achieved with a mixture of 0.5% heavy bupivacaine. The patients' hematocrit and serum electrolyte levels were obtained after six hours and compared with preoperative values. Hematocrit reduced from 40.32 ± 6.27 to 31.07 ± 5.40 (p < 0.001). Both serum sodium and potassium decreased from 136.77 ± 3.27 to 128.31 ± 5.91 and from 4.02 ± 0.26 to 3.81 ± 0.36, respectively (p < 0.001). However, serum chloride showed only a minimal increase from 101.58 ± 2.88 to 102.25 ± 1.66 (p < 0.12). Although the changes in serum sodium and potassium were statistically significant, they did not have any physiological consequences in our study. However, this emphasizes the importance of vigilant electrolyte monitoring to identify and mitigate the risk of electrolyte disturbances during TURP surgeries.

Comparison of the efficacy of 0.9% normal saline with balanced crystalloid (Plasmalyte) in maintaining the metabolic profile in head injury patients undergoing evacuation of acute subdural haematoma - A randomised controlled trial.

The choice of intravenous fluids is important in patients with traumatic brain injury (TBI), where large volumes may be required for resuscitation. Our study aimed to compare 0.9% normal saline (NS) with balanced crystalloid (Plasmalyte) in TBI patients in terms of metabolic and coagulation profile, brain relaxation score (BRS) and renal functions using serum urea, creatinine and urinary tissue inhibitor of metalloproteinases-2* insulin-like growth factor binding protein-7, [TIMP-2]*[IGFBP7], value to assess the risk of acute kidney injury. This randomised controlled trial on 90 TBI patients undergoing emergency craniotomy and subdural haematoma evacuation was conducted in a tertiary care institute. The patients were randomised to receive either NS (Group NS) or Plasmalyte (Group P) as the intraoperative maintenance fluid. The primary outcome measures included the potential of hydrogen (pH), base excess (BE) and chloride values from an arterial blood gas. The secondary outcomes were the coagulation profile, BRS and urinary [TIMP-2]*[IGFBP7]. The two groups' metabolic profile differences were analysed using two-way repeated analysis of variance. BRS was analysed using the Mann-Whitney U test. A P value < 0.05 was considered to be statistically significant. The pH and chloride values were significantly higher, and the BE values were significantly lower in Group P compared to Group NS (P < 0.001). Brain relaxation and coagulation profiles were comparable between the two groups. Serum creatinine (P = 0.002) and urinary [TIMP-2]*[IGFBP7] (P = 0.042) were significantly higher in the NS group. Plasmalyte maintains a more favourable metabolic profile than NS in TBI patients without affecting brain relaxation adversely.

Investigation of the single-phase immersion cold plate amid PAO-4 and Noah@3000A – An experimental approach and its numerical verification

This study investigates improving traditional immersion cooling systems by employing cold plates in single-phase immersion cooling with dielectric fluids (Noah@3000 A and PAO-4). Experimental and CFD methods explore various cold plate structures in a 1 U server with a TTV heat source. Flow rates range from 1 to 3 LPM, and configurations include side-open, fully enclosed, and dual-open designs. Results show that incorporating cold plates reduces fluid bypass, enhancing thermal performance. High-viscosity dielectric oil as a coolant yields substantial improvements (36.1% and 41.6% at low and high flow rates) compared to traditional systems. Thermal resistance decreases with higher flow rates, more notably for Noah@3000A. Immersing the cold plate in liquid enhances convective heat transfer, reducing thermal resistances by 7.2% and 9.4% for Noah@3000A and PAO-4 at low flow rates. Smaller fin pitch consistently lowers resistance by eliminating bypass. Outlet configuration significantly influences thermal resistance, with Enclosed cold plates showing the least performance for PAO-4 and dual-open cold plate yields the worst performance with Noah@3000A. Differences in heat transfer behavior between PAO-4 and Noah@3000A are linked to laminar and turbulent flow characteristics. These findings offer insights into optimizing immersion cooling systems, emphasizing the impact of fluid choice and cold plate design on thermal performance.

Goal-Directed Fluid Therapy Using Normal Saline versus Ringer's Lactate in Pediatric Neurosurgical Patients: A Randomized Controlled Trial

Abstract Background Ringer's lactate (RL) and 0.9% sodium chloride (NS) are used intraoperatively in pediatric surgical patients. The fluid of choice in pediatric neurosurgical patients is still under research. Hence, we compared NS and RL intraoperatively with a primary objective of measuring the absolute difference in serum chloride concentrations (ΔCl-) after surgery from baseline. Secondary objectives included changes in other electrolytes, osmolarity, pH, creatinine, brain relaxation score (BRS), and neurological outcome at discharge using a modified Rankin scale (mRS). Methods This prospective randomized trial was conducted in American Society of Anesthesiologists status I to II children, aged 6 months to 14 years, after Institutional Ethical Committee approval and written informed consent. Forty patients were randomized in group-S (received 0.9% Saline) and group-R (received RL). The fluid administration was guided by Pleth Variability Index (target &lt;13%). Arterial blood samples were taken at the start of surgery, during tumor resection, and at the end of surgery. Results Twenty-one patients in NS and 19 patients in RL were enrolled. ΔCl- was 12 (9–16) mmol/L in NS group and 4 (2–15) mmol/L in RL group, p = 0.03. NS group developed more metabolic acidosis (6 [28.6%] vs. 0 [0.0%], p = 0.021). There was no difference in the other electrolytes, serum osmolarity, BRS, perioperative creatinine, and mRS between groups, p = 0.36, p = 0.096, p = 0.658, and p = 0.168, respectively. Conclusion Intraoperative use of NS causes derangement in chloride balance, leading to metabolic acidosis compared to RL in children undergoing neurosurgical procedures. However, there was no difference in the other parameters, including serum osmolarity, BRS, and mRS.

Thermohydrodynamics of Bödewadt hybrid-nanofluid flow in a horizontal magnetic field

Since disks, rotating or stationary, are integral in many thermal systems, such as rotating heat exchangers, thermoelectric coolers, solar energy systems, and geothermal plants, this study scrutinizes the thermohydrodynamics of rotating hybrid nanofluid flow over a stretchable disk at rest. Further, the shape of the nanoparticles and the choice of base fluid substantially impact the enhancement of the heat transfer rate in various such thermal systems. Therefore, the present investigation considers engineered colloids made of four distinct (sphere, cylinder, column, lamina) titania and copper nanoparticle shapes in two different base fluids: water and engine-oil. The problem is formulated mathematically in an externally applied horizontal magnetic field and incorporating a non-Fourier heat flux model in the presence of solar radiation. Analogous to the case of the conventional vertical magnetic field, a similarity solution is also possible when magnetic forces act horizontally, both towards and opposite to the direction of rotation. Thus, the governing partial differential equations (PDEs) are first reduced to a set of highly non-linear and coupled ordinary differential equations (ODEs) via similarity transformations. These resulting set of ODEs are then solved numerically using a rapid and efficient spectral quasilinearization method (SQLM). Obtained results show that lamina-shaped TiO2−Cu/ engine-oil hybrid-nanofluid is a better choice than the other shapes of nanoparticle suspension in water. The horizontally applied magnetic field exhibits a stronger influence on the flow and heat transfer characteristics when compared to a vertical magnetic field. Additionally increasing the thermal relaxation parameter αt from 0.1 to 0.35, the Nusselt number boost by 24.44%, 23.41%, 22.54%, and 17.93% for sphere, cylinder, column, and lamina nanoparticles of TiO2−Cu/water hybrid nanofluid. In the case of TiO2−Cu/engine-oil hybrid-nanofluid augmenting αt from 0.1 to 0.35, the Nusselt number rise by 23.95%, 22.83%, 21.82%, and 15.89% for sphere, cylinder, column, and lamina nanoparticles. Based on their increasing NS and Be values, the various shapes follow the sequence: lamina ¡ column ¡ cylinder ¡ sphere. Furthermore, entropy generation can be optimized through the augmentation of solar radiation factors QSR, δ, along with the reduction of the magnetic interaction parameter M, and by a proper selection of nanoparticle’s shape. Interestingly, dual solutions are observed for the case of a shrinking disk, i.e., for S<0, and a linear temporal stability analysis reveals that only one of these two branches, namely the first solution branch, is stable and the second branch unstable.

Chaotic-flow-driven mixing in T- and V-shaped micromixers

T- and V-shaped (or arrow-shaped) micromixers enable the control of rapid chemical reactions by permitting accelerated mixing. Their mixing performance has been extensively investigated at moderate flow rates, which correspond to Reynolds numbers of the order of several hundreds. However, this operating range does not align with the recent applications of microreactors in organic synthesis. Therefore, this study examined mixing times in T- and V-shaped micromixers with 250-µm-wide channels at high flow rates (Reynolds numbers of up to 1500). The progress of mixing between an acidic solution and a basic solution containing a pH-sensitive fluorescent molecule was visualized by fluorescence microscopy imaging. An image analysis of 200 frames for each condition helped evaluate the degree of mixing and its stability over time under chaotic flow. The performance and stability of the V-shaped micromixer were significantly enhanced when the flow-rate ratio was changed from 1:1 to 1:2. The difference in momentum between the two inlet streams suppressed the undesirable alternation of the flow patterns at the junction. The effects of the choice of fluids (in the lower- and higher-flow-rate sides) on the reaction selectivity were explored through a numerical analysis. It was clarified that the substrate-side flow rate has to be set lower than that of the reactant side in the competing consecutive reaction system. Moreover, a short mixing time of 1 ms was achieved using the V-shaped micromixer at a flow-rate ratio of 1:2 and Re of 1500. These findings provide practical guidelines for the design and operation of microreactor systems.

Enhancing Lubrication Efficiency and Wear Resistance in Mechanical Systems through the Application of Nanofluids: A Comprehensive Review

Due to its potential to increase lubrication effectiveness and reduce wear, nanofluids have drawn substantial interest in the field of mechanical systems. Colloidal suspensions of nanoparticles dispersed across a base fluid to create nanofluids. This comprehensive study's goal is to examine recent developments, scientific discoveries, and possible applications of nanofluids in tribology. The scientific and technical characteristics of materials which move in relation to one another are the subject of the academic topic of tribology. The aim of this review paper includes a thorough investigation of phenomena like lubrication mechanism, wear and friction. Because of their unique features at the nanoscale, nanoparticles offer a special opportunity to mitigate enduring problems in tribological systems. This review critically evaluates the process utilized to create nanofluids, examines their tribological properties, and considers how they affect the effectiveness of how mechanical systems function. The higher lubrication effectiveness and wear resistance are the main points of attention. This study also investigates several methods for characterizing nanofluids to examine their behavior. The assessment also emphasizes important elements that affect the effectiveness of nanofluids, including the composition, concentration, size, and choice of nanoparticles, in addition to the choice of the base fluid. This study examines many problems and probable future endeavors within the industry, encompassing inquiries pertaining to long-term durability, and scalability. The primary objective of this review paper is to conduct a comprehensive analysis of the current state of nanofluid research within the domain of tribology. The objective is to foster further progress and encourage the extensive adoption of nanofluids as an innovative lubricating technology.

Optimization of a three-stage cascade refrigeration system operating with natural refrigerants to produce low temperatures by applying a bio-inspired method

With the growing global energy consumption, on the first hand, and the need to produce low temperatures on the second hand, therefore the technological challenges consist in minimizing greenhouse gas emissions by reducing the energy consumption. In fact, in refrigeration, this consists of the use of environmentally friendly refrigerants (GWP < 150) with the optimization of cold production processes. In this context, several optimization methods have been tested, and the objective of this work to seek the most reliable method to optimize a three-stage cascade vapor compression refrigeration system. Regarding refrigerants, hydrocarbons can be a solution, the R50/R1150/R290 and R50/R1150/R1270 groups are selected and used here to produce temperatures ranging from −160 °C to −120 °C. After comparing seven (7) nature-inspired optimization methods, the JSOA bio-inspired optimization method is applied. Energetic, exergetic and environmental analyzes are also applied to determine the optimal operating point that allows both the minimization of energy consumption and TEWI (Total Equivalent Warming Impact). A pragmatic comparison between the two considered groups provides insights into the choice of high-temperature sub-cycle fluid, and it is found that R290 shows better results compared to R1270.

A novel approach for designing efficient and sustainable cooling cycles with low global warming potential refrigerants

With the current legislation on the phase-out of 3rd generation refrigerants, new cooling cycles are expected to operate with 4th generation refrigerants, hence, the need for optimal system performance with these new working fluids. In this study, an innovative optimization approach was applied for the design of cooling cycles with 4th generation refrigerants based on integrating statistical analysis design of experiments (DoE) with molecular modeling using the polar soft-SAFT model. First, a detailed multi-criteria assessment was applied for the selection of 4th generation refrigerants in medium–low temperature applications. Results demonstrated the potentiality of trans-1,3,3,3-tetrafluoroprop-1-ene (R1234ze(E)) or cis-1,2,3,3,3-pentafluoroprop-1-ene (R1225ye(Z)) in terms of environmental, safety, and technical criteria in basic cooling cycles under specific operating conditions. Multi-objective optimization guided using statistical analysis tools were implemented to study potential enhancement in cooling cycle performance using these promising refrigerants in terms of energy and exergy efficiency. This included evaporator and condenser temperature, fluid choice, compression yield, superheating/subcooling degrees, and cycle type. The evaporation and condenser temperature, and the compressor efficiency are shown to monopolize more than three-quarters of the cumulative contribution on system efficiency for those operated with R1234ze(E) in advanced liquid-to-suction line heat exchangers (LL/SL-IHX). Further optimization through examining the effect of heat transfer phenomena assisted in determining optimal operating conditions for new systems operating with low GWP refrigerants, instilling annual cost savings of $1.59 K and reduction in CO2 emissions by 1.02 tCO2-eq compared to the baseline system.

Ciecz buforowa i metoda jej przygotowania w celu wykonania korków cementowych

The study of extensive material on the results of well cementing in various regions of the world shows that the quality of plugging operations is largely determined by the degree of displacement of the drilling fluid from the well. No one has ever specifically developed a buffer fluid for plugback cementing. When carrying out reverse cementing, determining the end time of the cementing process is of great importance, which largely depends on the choice of buffer fluid. The purpose of this work is to give the buffer fluid the properties of a magnetic locking element during plugback cementing of casing strings while increasing its separating ability. To achieve this, carboxymethyl cellulose is additionally dissolved in water before the displacement of the components when preparing a buffer liquid. Rubber crumbs are then mixed with the filler, and mixing is carried out under a pressure of at least 0.2 MPa. The buffer liquid contains the following components in the following wt.% ratios: carboxymethylcellulose 4–5, crumb rubber 7–8, ferromagnetic metal powder 15–16, with the remaining portion being water. The buffer fluid of the optimal composition not only maintains no less (than 98%) displacing power, but also exhibits an exceptionally low filler fall rate (when diluted by half). Furthermore, it does not linger in a pipe with an open end and an annular magnet inside, preventing settling plugs. The economic benefits of using a buffer fluid primarily stems from ensuring reliable control over the filling of the annular space with cement slurry, preventing its pumping from the annulus to the intracasing space, and preventing clogging of the productive underlying formation with cement.

Regional Practice Variation and Outcomes in the Standard Versus Accelerated Initiation of Renal Replacement Therapy in Acute Kidney Injury (STARRT-AKI) Trial: A Post Hoc Secondary Analysis.

Among patients with severe acute kidney injury (AKI) admitted to the ICU in high-income countries, regional practice variations for fluid balance (FB) management, timing, and choice of renal replacement therapy (RRT) modality may be significant. Secondary post hoc analysis of the STandard vs. Accelerated initiation of Renal Replacement Therapy in Acute Kidney Injury (STARRT-AKI) trial (ClinicalTrials.gov number NCT02568722). One hundred-fifty-three ICUs in 13 countries. Altogether 2693 critically ill patients with AKI, of whom 994 were North American, 1143 European, and 556 from Australia and New Zealand (ANZ). None. Total mean FB to a maximum of 14 days was +7199 mL in North America, +5641 mL in Europe, and +2211 mL in ANZ (p < 0.001). The median time to RRT initiation among patients allocated to the standard strategy was longest in Europe compared with North America and ANZ (p < 0.001; p < 0.001). Continuous RRT was the initial RRT modality in 60.8% of patients in North America and 56.8% of patients in Europe, compared with 96.4% of patients in ANZ (p < 0.001). After adjustment for predefined baseline characteristics, compared with North American and European patients, those in ANZ were more likely to survive to ICU (p < 0.001) and hospital discharge (p < 0.001) and to 90 days (for ANZ vs. Europe: risk difference [RD], -11.3%; 95% CI, -17.7% to -4.8%; p < 0.001 and for ANZ vs. North America: RD, -10.3%; 95% CI, -17.5% to -3.1%; p = 0.007). Among STARRT-AKI trial centers, significant regional practice variation exists regarding FB, timing of initiation of RRT, and initial use of continuous RRT. After adjustment, such practice variation was associated with lower ICU and hospital stay and 90-day mortality among ANZ patients compared with other regions.

Separation of Oral Cooling and Warming Requires TRPM8.

Cooling sensations arise inside the mouth during ingestive and homeostasis behaviors. Oral presence of cooling temperature engages the cold and menthol receptor TRPM8 (transient receptor potential melastatin 8) on trigeminal afferents. Yet, how TRPM8 influences brain and behavioral responses to oral temperature is undefined. Here we used in vivo neurophysiology to record action potentials stimulated by cooling and warming of oral tissues from trigeminal nucleus caudalis neurons in female and male wild-type and TRPM8 gene deficient mice. Using these lines, we also measured orobehavioral licking responses to cool and warm water in a novel, temperature-controlled fluid choice test. Capture of antidromic electrophysiological responses to thalamic stimulation identified that wild-type central trigeminal neurons showed diverse responses to oral cooling. Some neurons displayed relatively strong excitation to cold <10°C (COLD neurons) while others responded to only a segment of mild cool temperatures below 30°C (COOL neurons). Notably, TRPM8 deficient mice retained COLD-type but lacked COOL cells. This deficit impaired population responses to mild cooling temperatures below 30°C and allowed warmth-like (≥35°C) neural activity to pervade the normally innocuous cool temperature range, predicting TRPM8 deficient mice would show anomalously similar orobehavioral responses to warm and cool temperatures. Accordingly, TRPM8 deficient mice avoided both warm (35°C) and mild cool (≤30°C) water and sought colder temperatures in fluid licking tests, whereas control mice avoided warm but were indifferent to mild cool and colder water. Results imply TRPM8 input separates cool from warm temperature sensing and suggest other thermoreceptors also participate in oral cooling sensation.

A balancing act: drifting away from the reflexive use of "ab"normal saline.

Maintenance intravenous fluids are the most frequently ordered medications for hospitalized children. Since the American Association of Pediatrics published national guidelines, there has been an increased reflexive use of isotonic solutions, especially 0.9% saline, as a prophylaxis against hyponatremia. In this educational review, we discuss the potential deleterious effects of using 0.9% saline, including the development of hyperchloremia, metabolic acidosis, acute kidney injury, hyperkalemia, and a proinflammatory state. Balanced solutions with anion buffers cause relatively minimal harm when used in most children. While the literature supporting one fluid choice over the other is variable, we highlight the benefits of balanced solutions over saline and the importance of prescribing fluid therapy that is individualized for each patient.

Efficacy of intraoperative irrigation with artificial cerebrospinal fluid in chronic subdural hematoma surgery: study protocol for a multicenter randomized controlled trial

BackgroundThe surgical techniques for treatment of chronic subdural hematoma (CSDH), a common neurosurgical condition, have been discussed in a lot of clinical literature. However, the recurrence proportion after CSDH surgery remains high, ranging from 10 to 20%. The standard surgical procedure for CSDH involves a craniostomy to evacuate the hematoma, but irrigating the hematoma cavity during the procedure is debatable. The authors hypothesized that the choice of irrigation fluid might be a key factor affecting the outcomes of surgery. This multicenter randomized controlled trial aims to investigate whether intraoperative irrigation using artificial cerebrospinal fluid (ACF) followed by the placement of a subdural drain would yield superior results compared to the placement of a subdural drain alone for CSDH.MethodsThe study will be conducted across 19 neurosurgical departments in Japan. The 1186 eligible patients will be randomly allocated to two groups: irrigation using ACF or not. In either group, a subdural drain is to be placed for at least 12 h postoperatively. Similar to what was done in previous studies, we set the proportion of patients that meet the criteria for ipsilateral reoperation at 7% in the irrigation group and 12% in the non-irrigation group. The primary endpoint is the proportion of patients who meet the criteria for ipsilateral reoperation within 6 months of surgery (clinical worsening of symptoms and increased hematoma on imaging compared with the postoperative state). The secondary endpoints are the proportion of reoperations within 6 months, the proportion being stratified by preoperative hematoma architecture by computed tomography (CT) scan, neurological symptoms, patient condition, mortality at 6 months, complications associated with surgery, length of hospital stay from surgery to discharge, and time of the surgical procedure.DiscussionWe present the study protocol for a multicenter randomized controlled trial to investigate our hypothesis that intraoperative irrigation with ACF reduces the recurrence proportion after the removal of chronic subdural hematomas compared with no irrigation.Trial registrationClinicalTrials.gov jRCT1041220124. Registered on January 13, 2023.