Fluid distribution during surgery in the flat recumbent, Trendelenburg, and the reverse Trendelenburg body positions.

BACKGROUND: The distribution and elimination of infused crystalloid fluid is known to be affected by general anesthesia, but it is unclear whether changes differ depending on whether the patient is operated in the flat recumbent position, the Trendelenburg ("legs up") position, or the reverse Trendelenburg ("head up") position. METHODS: Retrospective data on hemodilution and urine output obtained during and after infusion of 1-2 L of Ringer's solution over 30-60 min were collected from 61 patients undergoing surgery under general anesthesia and 106 volunteers matched with respect to the infusion volume and infusion time. Parameters describing fluid distribution in the anesthetized and awake subjects were compared by population volume kinetic analysis. RESULTS: General anesthesia decreased the rate constant for urine output by 79% (flat recumbent), 91% (legs up) and 91% (head up), suggesting that laparoscopic surgery per se intensified the already strong anesthesia-induced fluid retention. General anesthesia also decreased the rate constant governing the return of the distributed fluid to the plasma by 32%, 15%, and 70%, respectively. These results agree with laboratory data showing a depressive effect of anesthetic drugs on lymphatic pumping, and further suggest that the "legs up" position facilitates lymphatic flow, whereas the "head up" position slows this flow. Both Trendelenburg positions increased swelling of the "third fluid space". CONCLUSIONS: General anesthesia caused retention of infused fluid with preferential distribution to the extravascular space. Both Trendelenburg positions had a modifying influence on the kinetic adaptations that agreed with the gravitational forces inflicted by tilting to body.

The patterns in urine excretion and transvascular fluid exchange in human subjects during intravenous fluid infusion: A quantitative analysis.

INTRODUCTION: Investigations of responses of animals and humans to changes of plasma volume are usually reported as average responses of groups of individuals. This ignores considerable quantitative variation between individuals. We examined the hypothesis that individual responses follow a common temporal pattern with variations reflecting different parameters describing that pattern. METHODS: We illustrate this approach using data of Hahn, Lindahl and Drobin (Acta Anaesthesiol Scand.2011, 55:987-94) who measured urine volume and haemoglobin dilution of 10 female subjects during intravenous Ringer infusions for 30 min and subsequent 3.5 h. The published time courses were digitised and analysed to determine if a family of mathematical functions accounted for the variation in individual responses. RESULTS: Urine excretion was characterised by a time delay (Td) before urine flow increased and a time course of cumulative urine excretion described by a logarithmic function. This logarithmic relation forms the theoretical basis of a family of linear relations describing urine excretion as a function of Td. Measurement of Td enables estimation of subsequent values of urine excretion and thereby the fraction of infused fluid retained in the body. CONCLUSION: The approach might be useful for physiologists and clinical investigators to compare the response to infusion protocols when both test and control responses can be described by linear relations between cumulative urine volume at specific times and Td. The approach may also be useful for clinicians by complementing strategies to guide fluid therapy by enabling the later responses of an individual to be predicted from their earlier response.

Effects of different types of Ringer's solution on patients with traumatic haemorrhagic shock: a prospective cohort study.

OBJECTIVE: To compare the fluid resuscitation effect of sodium acetate Ringer's solution and sodium bicarbonate Ringer's solution on patients with traumatic haemorrhagic shock. METHOD: We conducted a prospective cohort study in our emergency department on a total of 71 patients with traumatic haemorrhagic shock admitted between 1 December 2020 and 28 February 2022. Based on the time of admission, patients were randomly divided into a sodium bicarbonate Ringer's solution group and sodium acetate Ringer's solution group, and a limited rehydration resuscitation strategy was adopted in both groups. General data were collected separately, and the patients' vital signs (body temperature, respiration, blood pressure and mean arterial pressure (MAP)), blood gas indices (pH, calculated bicarbonate (cHCO3-), partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (pCO2) and clearance of lactate (CLac)), shock indices, peripheral platelet counts, prothrombin times and plasma fibrinogen levels were measured and compared before and 1 h after resuscitation. RESULTS: The post-resuscitation heart rate of the sodium bicarbonate Ringer's solution group was significantly lower than that of the sodium acetate Ringer's solution group (p < 0.05), and the MAP was also significantly lower (p < 0.05). The patients in the sodium bicarbonate Ringer's solution group had significantly higher pH, cHCO3- and PaO2 values and lower pCO2 and CLac values (p < 0.05) than those in the sodium acetate Ringer's solution group, and the post-resuscitation peripheral platelet counts and fibrinogen levels were significantly higher, with shorter plasma prothrombin times and smaller shock indices (p < 0.001). CONCLUSION: Sodium bicarbonate Ringer's solution is beneficial for maintaining MAP at a low level after resuscitation. The use of sodium bicarbonate Ringer's solution in limited fluid resuscitation has positive results and is of high clinical value.

Comparison of bicarbonate Ringer's solution with lactated Ringer's solution among postoperative outcomes in patients with laparoscopic right hemihepatectomy: a single-centre randomised controlled trial.

The study was aimed to investigate the positive impact of bicarbonate Ringer's solution on postoperative outcomes in patients who underwent laparoscopic right hemihepatectomy. Patients in the two groups were infused with lactated Ringer's solution (LRS, n = 38) and the bicarbonate Ringer's solution (BRS, n = 38) at a rate of 5 ml·kg-1·h-1. The stroke volume was monitored and 200 ml of hydroxyethyl starch with 130/0.4 sodium chloride injection (Hes) of a bolus was given in the first 5-10 min. The main outcome was to test lactic acid (LAC) concentration before and after surgery. The concentrations of LAC in the LRS group were higher than in the BRS group at 2 h after operation began, at the end of the operation and 2 h after the operation. Overall, the parameters including pH, base excess (BE), HCO3-, aspartate transaminase (AST) and alanine transaminase (ALT) were improved. The values of bilirubin in the LRS group were higher and albumin were lower than in the BRS group at post-operation 1st and 2nd day (P<0.05). The time of prothrombin time (PT) and activated partial thromboplastin time (APTT) in the LRS group were longer than that in the BRS group at post-operation 1st and 2nd day (P<0.05). Likewise, the concentrations of Mg2+, Na+ and K+ also varied significantly. The length of hospital was reduced, and the incidence of premature ventricular contractions (P = 0.042) and total complications (P = 0.016) were lower in group BRS. TRIAL REGISTRATION: The study was registered at clinicalTrials.gov with the number ChiCTR2000038077 on 09/09/2020.

EFFECT OF MIR-21-3P ON INTESTINAL INJURY IN RATS WITH TRAUMATIC HEMORRHAGIC SHOCK RESUSCITATED WITH THE SODIUM BICARBONATE RINGER'S SOLUTION.

ABSTRACT: Background : This study aims to determine the impact and mechanism of miR-21-3p on intestinal injury and intestinal glycocalyx during fluid resuscitation in traumatic hemorrhagic shock (THS), and the different impacts of sodium lactate Ringer's solution (LRS) and sodium bicarbonate Ringer's solution (BRS) for resuscitation on intestinal damage. Methods : A rat model of THS was induced by hemorrhage from the left femur fracture. The pathological changes of intestinal tissues and glycocalyx structure were observed by hematoxylin-eosin staining and transmission electron microscope. MiR-21-3p expression in intestinal tissues was detected by real-time quantitative polymerase chain reaction. The expression of glycocalyx-, cell junction-, and PI3K/Akt/NF-κB signaling pathway-related proteins was analyzed by western blot. Results : MiR-21-3p expression was increased in THS rats, which was suppressed by resuscitation with BRS. BRS or LRS aggravated the intestinal injury and damaged intestinal glycocalyx in THS rats. The expression of SDC-1, HPA, ß-catenin, MMP2, and MMP9 was upregulated, the expression of E-cad was downregulated, and the PI3K/Akt/NF-κB signaling pathway was activated in THS rats, which were further aggravated by BRS or LRS. The adverse effect of LRS was more serious than BRS. MiR-21-3p overexpression deteriorated the injury of intestinal tissues and intestinal glycocalyx; increased the expression of SDC-1, HPA, ß-catenin, MMP2, and MMP9 while decreasing E-cad expression; and activated the PI3K/Akt/NF-κB signaling pathway in BRS-resuscitated THS rats. Conclusion : MiR-21-3p aggravated intestinal tissue injury and intestinal glycocalyx damage through activating PI3K/Akt/NF-κB signaling pathway in rats with THS resuscitated with BRS.

The combination of hydrogen gas and hydrogen-rich solution does not protect against ischemic spinal cord injury in rabbits.

PURPOSE: This study aimed to determine whether the combination of H2 gas inhalation and administration of hydrogen-rich acetated Ringer's solution (HS) could protect against ischemic spinal cord injury in rabbits. METHODS: In Experiment 1, rabbits were randomly assigned to a 1.2% H2 gas group, HS group, 1.2% H2 gas + HS group (combination group), or control group (n = 6 per group). The H2 concentration of HS was 0.65 mM. H2 was inhaled for 60 min, starting 5 min before reperfusion. HS (20 mL/kg) was divided into six bolus injections at 10-min intervals, starting 5 min before reperfusion. Spinal cord ischemia was produced by occluding the abdominal aorta for 15 min. Neurologic and histopathologic evaluations were performed 7 days after reperfusion. In Experiment 2, H2 concentrations in spinal cord tissue according to the administration of 1.2% H2 gas or HS were compared by measuring the electric current through a platinum needle electrode (n = 2). In Experiment 3, rabbits were assigned to a 2% H2 gas group or control group (n = 6 per group). Spinal cord ischemia was produced and neurologic and histopathologic evaluations were performed as in Experiment 1. RESULTS: There were no significant differences among the groups in the neurologic and histopathologic outcomes in Experiments 1 and 3. Bolus administration of HS (10 mL) transiently increased the current to only 1/30th and 1/27th of the plateau current with 1.2% H2 gas inhalation in two animals. CONCLUSION: These results suggest that the combination of 1.2% H2 gas inhalation and administration of a hydrogen-rich solution does not protect against ischemic spinal cord injury and that the increase in H2 concentration in spinal cord tissue after administration of HS is very low compared to 1.2% H2 gas inhalation.

Ex vivo storage of human osteochondral allografts: Long-term analysis over 300 days using a Ringer-based solution.

Large osteochondral defects are a major challenge in orthopedics, for which osteochondral allograft (OCA) transplantation is nowadays considered as an option, especially in young patients. However, a major issue with OCA is the need for graft storage, which ensures adequate cartilage integrity over time. The aim of this study was to test how long a Ringer-based storage solution can provide good graft quality after explantation and thus meet the requirements for OCA. For this purpose, human osteochondral allografts of the knee and ankle were analyzed. Live/Dead analysis was performed and glycosaminoglycan, as well as hydroxyproline content, were measured as crucial chondrocyte integrity factors. Furthermore, biomechanical tests focusing on stress relaxation and elastic compression modulus were performed. The critical value of 70% living chondrocytes, which corresponds to a number of 300 cells/mm², was reached after an average of 16 weeks of storage. In addition, a constant cell shrinkage was observed over time. The amount of glycosaminoglycan and hydroxyroline showed a slight and constant decrease over time, but no significant differences when compared from Day 0 to the values at Weeks 40-43. Biomechanical testing also revealed no significant differences at the different time points. Therefore, the results show that the Ringer-based storage solution at 4°C is able to provide a chondrocyte survival of 70% until Week 16. This is comparable to previously published storage solutions. Therefore, the study contributes to the establishment of a Ringer-based osteochondral allograft transplantation system for countries where medium-based storage solution cannot be approved.

Blood volume and hemodynamics during treatment of major hemorrhage with Ringer solution, 5% albumin, and 20% albumin: a single-center randomized controlled trial.

BACKGROUND: Volume replacement with crystalloid fluid is the conventional treatment of hemorrhage. We challenged whether a standardized amount of 5% or 20% albumin could be a viable option to maintain the blood volume during surgery associated with major hemorrhage. Therefore, the aim of this study was to quantify and compare the plasma volume expansion properties of 5% albumin, 20% albumin, and Ringer-lactate, when infused during major surgery. METHODS: In this single-center randomized controlled trial, fluid replacement therapy to combat hypovolemia during the hemorrhagic phase of cystectomy was randomly allocated in 42 patients to receive either 5% albumin (12 mL/kg) or 20% albumin (3 mL/kg) over 30 min at the beginning of the hemorrhagic phase, both completed by a Ringer-lactate replacing blood loss in a 1:1 ratio, or Ringer-lactate alone to replace blood loss in a 3:1 ratio. Measurements of blood hemoglobin over 5 h were used to estimate the effectiveness of each fluid to expand the blood volume using the following regression equation: blood loss plus blood volume expansion = factor + volume of infused albumin + volume of infused Ringer-lactate. RESULTS: The median hemorrhage was 848 mL [IQR: 615-1145]. The regression equation showed that the Ringer-lactate solution expanded the plasma volume by 0.18 times the infused volume while the corresponding power of 5% and 20% albumin was 0.74 and 2.09, respectively. The Ringer-lactate only fluid program resulted in slight hypovolemia (mean, - 313 mL). The 5% and 20% albumin programs were more effective in filling the vascular system; this was evidenced by blood volume changes of only + 63 mL and - 44 mL, respectively, by long-lasting plasma volume expansion with median half time of 5.5 h and 4.8 h, respectively, and by an increase in the central venous pressure. CONCLUSION: The power to expand the plasma volume was 4 and almost 12 times greater for 5% albumin and 20% albumin than for Ringer-lactate, and the effect was sustained over 5 h. The clinical efficacy of albumin during major hemorrhage was quite similar to previous studies with no hemorrhage. TRIAL REGISTRATION: ClinicalTrials.gov NCT05391607, date of registration May 26, 2022.

ACETATE RINGER'S SOLUTION VERSUS NORMAL SALINE SOLUTION IN SEPSIS: A RANDOMIZED, CONTROLLED TRIAL.

ABSTRACT: Background: Normal saline solution (NSS) and Ringer's acetate solution (RAS) are commonly given to critically ill patients as a fundamental fluid therapy. However, the effect of RAS and NSS on sepsis patient outcomes remains unknown. Methods: We conducted a single-center prospective open-label parallel controlled trial to enroll adult patients (>18 years old) diagnosed with sepsis. Participants received either RAS or NSS for intravenous infusion for 5 days. The primary outcome was the incidence of major adverse kidney events within 28 days (MAKE28). Secondary outcomes included 30-/90-day mortality, acute kidney injury, and hyperchloremia. The patients were then reclassified as NSS-only, RAS-only, and RAS + NSS groups according to the type of fluid they had received before enrollment. Thereafter, a secondary post hoc analysis was performed. Results: Two hundred fifty-five septic patients were screened, and 143 patients (51.0% in RAS group and 49.0% in NSS group) were enrolled in the study. Each group received a median of 2 L of fluid administration during five interventional days. Of the patients, 39.3% had received 500 mL (500-1,000 mL) of balanced salt solutions (BSSs) before intensive care unit (ICU) admission. There was no statistical difference among the RAS and NSS group on the primary outcome MAKE28 in the initial analysis (23.3% vs. 20.0%; OR, 1.2 [0.6 to 2.2]; P = 0.69). MAKE28 was observed in 23.3% of RAS-only versus 27.3% of NSS-only group patients (0.82 [0.35-1.94], P = 0.65) in the secondary post hoc analysis. The patients in the NSS-only group had a longer invasive mechanical ventilation days and a trend toward the accumulation of serum chloride. Conclusion: This study observed no statistically significant difference on MAKE28 and secondary outcomes among sepsis patients receiving RAS and NSS. However, it is unclear whether the large amount of fluid resuscitation before ICU admission and carrier NSS narrowed the difference between BSSs and NSSs.

Sodium bicarbonate Ringer's solution for hemorrhagic shock: A meta-analysis comparing crystalloid solutions.

BACKGROUND: The choice of fluid resuscitation in Traumatic Hemorrhagic shock (THS) remains a critical aspect of patient management. Bicarbonated Ringers solution (BRS) has shown promise due to its composition resembling human Extracellular Fluid and its potential benefits on hemodynamics. OBJECTIVE: To evaluate the efficacy, mortality rates, hemodynamic effects, and adverse outcomes of Sodium Bicarbonate Ringer's Solution in the treatment of hemorrhagic shock, as compared to other relevant interventions. METHOD: A comprehensive examination of the available literature was performed by conducting systematic searches in prominent databases such as Cochrane, EMBASE, MEDLINE, and PubMed. The process employed predefined criteria to extract relevant data and evaluate the quality of the studies. The outcome measures considered encompassed survival rates, mortality, mean arterial pressure (MAP), heart rate (HR), and adverse events. RESULT: The meta-analysis of three studies showed that compared to the other crystalloids, the use of BRS had an odds ratio for survival of 1.86 (95% CI: 0.94, 3.71; p = 0.08; I2 = 0%), an odds ratio for total adverse events of 0.14 (95% CI: 0.06, 0.35; p < 0.0001; I2 = 22%), a mean difference in heart rate of -4.49 (95% CI: -7.55, -1.44; p = 0.004; I2 = 13%), and a mean difference in mean arterial pressure of 2.31 (95% CI: -0.85, 5.47; p = 0.15; I2 = 66%). CONCLUSION: BRS demonstrated a significant reduction in complications, including adult respiratory distress syndrome (ARDS), Multiple Organ Dysfunction (MODS), and Total Adverse Effects, when compared to other solutions in the treatment of THS. Additionally, THS patients resuscitated with BRS experienced a notable decrease in heart rate. The findings suggest BRS may contribute to organ stability and potential survival improvement due to its similarity to human Extracellular Fluid and minimal impact on the liver.

Effect of sodium bicarbonate Ringer's solution on lung injury in rats with traumatic hemorrhagic shock.

This study aimed to explore the impact of different pH values of resuscitation fluid on traumatic hemorrhagic shock (THS), focusing on their effects on glycocalyx and inflammation. A rat model of THS was induced by hemorrhage from a left femur fracture, while an oxygen-glucose deprivation/reoxygenation (OGD/R)-induced HULEC-5a cell model was considered as an in vitro THS model. The lung tissue pathology and glycocalyx structure were assessed through hematoxylin-eosin (H&E) staining and transmission electron microscope examination. The levels of glycocalyx-related factors and inflammation-related factors were determined by enzyme-linked immunosorbent assay (ELISA). The expression of glycocalyx-related proteins, cell junction-related proteins, and proteins involved in the PI3K/Akt/NF-κB signaling pathway was analyzed by western blot. The results showed that both sodium bicarbonate Ringer's solution (BRS) and lactate Ringer's solution (LRS) were effective in restoring mean arterial pressure and heart rate in THS rats. However, LRS has a stronger impact on promoting inflammation and damaging the glycocalyx compared with BRS. In OGD/R-induced HULEC-5a cells, a pH of 7.4 and 6.5 increased inflammation and disrupted the glycocalyx, while a pH of 8.1 had no significant effect on inflammation or glycocalyx. Furthermore, the PI3K/Akt/NF-κB signaling pathway was activated by fluid resuscitation and different pH values. However, the activating effect of BRS and pH 8.1 on the PI3K/Akt/NF-κB signaling pathway was milder compared with LRS and pH6.5. In conclusion, an alkaline recovery environment was more beneficial for the treatment of THS.

A Slow-Exchange Interstitial Fluid Compartment in Volunteers and Anesthetized Patients: Kinetic Analysis and Physiology.

BACKGROUND: Physiological studies suggest that the interstitial space contains 2 fluid compartments, but no analysis has been performed to quantify their sizes and turnover rates. METHODS: Retrospective data were retrieved from 270 experiments where Ringer's solution of between 238 and 2750 mL (mean, 1487 mL) had been administered by intravenous infusion to awake and anesthetized humans (mean age 39 years, 47% females). Urinary excretion and hemoglobin-derived plasma dilution served as input variables in a volume kinetic analysis using mixed-models software. RESULTS: The kinetic analysis successfully separated 2 interstitial fluid compartments. One equilibrated rapidly with the plasma and the other equilibrated slowly. General anesthesia doubled the rate constants for fluid entering these 2 compartments (from 0.072 to 0.155 and from 0.026 to 0.080 min -1 , respectively). The return flows to the plasma were impeded by intensive fluid therapy; the rate constant for the fast-exchange compartment decreased from 0.251 to 0.050 when the infusion time increased from 15 to 60 minutes, and the rate constant for the slow-exchange compartment decreased from 0.019 to 0.005 when the infused volume increased from 500 to 1500 mL. The slow-exchange compartment became disproportionately expanded when larger fluid volumes were infused and even attained an unphysiologically large size when general anesthesia was added, suggesting that the flow of fluid was restrained and not solely determined by hydrostatic and oncotic forces. The dependence of the slow-exchange compartment on general anesthesia, crystalloid infusion rate, and infusion volume all suggest a causal physiological process. CONCLUSIONS: Kinetic analysis supported that Ringer's solution distributes in 2 interstitial compartments with different turnover times. The slow compartment became dominant when large amounts of fluid were infused and during general anesthesia. These findings may explain why fluid accumulates in peripheral tissues during surgery and why infused fluid can remain in the body for several days after general anesthesia.

Prognosis for major abdominal surgeries based on intraoperative low-dose nutrition: A metabolic perspective.

BACKGROUND & AIMS: The optimal nutrition intake during surgery is unknown. This study aimed to investigate the prognosis of low-dose nutrition during laparoscopic colorectal cancer surgery. METHODS: In the glucose and amino acids (GA) group, 20 patients were infused with glucose (75 g/L) and amino acids (30 g/L) at 60 mL/h and bicarbonate Ringer's solution. However, 20 patients in the control (C) group were infused with bicarbonate Ringer's solution without GA. The length of hospital stay was determined, and measurements were taken before (TI) and after (T2) the surgery under general anesthesia. RESULTS: The lengths of hospital stay were comparable between the GA (13 days) and C (16 days) groups. Ketone body levels were 294 (C group) and 33 (GA group) µmol/L at T2. Nitrogen balance was 0.32 g (GA group) and -1.60 g (C group) at T2. CONCLUSIONS: Although the lengths of hospital stay were comparable, ketone body levels, and nitrogen balance were significantly different (P < 0.01) between the two groups after surgery.

[Potential for infusion correction of COVID-19-associated endotheliopathy].

AIM: To evaluate the relationship between the systemic inflammatory response and the severity of COVID-19-associated endotheliopathy and the effect of succinate-containing crystalloid solution (sodium meglumine succinate) on it in patients with severe COVID-19. MATERIALS AND METHODS: Clinical and laboratory parameters of 53 intensive care unit's patients with COVID-19 complicated by community-acquired bilateral multisegmental pneumonia were analyzed. Intensive therapy complex of 27 patients (study group) included daily infusion of 1.5% solution of sodium meglumine succinate (Reamberin) in the daily dose of 10 ml/kg for at least 11 days (or during the whole stay in the unit). A similar volume of Ringer's solution was present in the control group of 26 patients. The levels of endotheliocytosis, homocysteine, and systemic inflammatory response were determined at all stages of the study. RESULTS: The evaluation of endotheliopathy degree in the meglumine succinate group showed a significant reduction of initially elevated levels of endotheliemia and homocysteinemia at all study stages. The pattern of changes in the study group was highly correlated (r=0.90-0.96) with the dynamics of systemic inflammatory response parameters-fibrinogenemia, C-reactive protein and interleukin-6 levels. As normalization of the immune imbalance, we regarded the termination of lymphopenia in the Reamberin group. CONCLUSION: Early inclusion of Reamberin infusion into intensive therapy of severe COVID-19, in comparison with Ringer's solution, leads to significant and stable correction of the severity of systemic inflammatory response, which in turn is naturally reflected in the severity of endothelial dysfunction, multiple organ failure, and also leads to a decrease in 28-day mortality.

Bicarbonate ringer's solution could improve the intraoperative acid-base equilibrium and reduce hepatocellular enzyme levels after deceased donor liver transplantation: a randomized controlled study.

BACKGROUND: Bicarbonate Ringer's (BR) solution is a direct liver and kidney metabolism-independent HCO3- buffering system. We hypothesized that BR solution would be more effective in improving acid-base equilibrium and more conducive to better liver function than Acetate Ringer's (AR) solution in conventional orthotopic liver transplantation (OLT) patients. METHODS: Sixty-nine adult patients underwent OLT. Patients in the bicarbonate and acetate groups received BR solution or AR solution as infused crystalloids and graft washing solution, respectively. The primary outcome was the effect on pH and base excess (BE) levels. The secondary outcome measures were the incidence and volume of intraoperative 5% sodium bicarbonate infusion and laboratory indicates of liver and kidney function. RESULTS: The pH and absolute BE values changed significantly during the anhepatic phase and immediately after transplanted liver reperfusion in the bicarbonate group compared with the acetate group (all P < 0.05). The incidence and volume of 5% sodium bicarbonate infusion were lower in the bicarbonate group than in the acetate group (all P < 0.05). The aspartate transaminase (AST) level at 7 postoperative days and the creatine level at 30 postoperative days were significantly higher in the acetate group than in the bicarbonate group (all P < 0.05). CONCLUSION: Compared with AR solution, BR solution was associated with improved intraoperative acid-base balance and potentially protected early postoperative liver graft function and reduced late-postoperative renal injury.

Implications of ageing effects on thermal and mechanical properties of PMMA-based bone cement for THA revision surgery.

Loosening and infection are the main reasons for revision surgery in total hip arthroplasty (THA). Removing partially detached cemented implant components during revision surgery remains challenging and poses the risk of periprosthetic bone damage. A promising approach for a gentler removal of partially detached prostheses involves softening the PMMA-based bone cement by heating it above its glass transition temperature (TG), thus loosening the implant-cement bond. It is assumed that the TG of PMMA-based bone cement decreases in-vivo due to the gradual absorption of body fluid. Reliable data on TG are essential to develop a heat-based method for removing cemented implant components during revision surgery. The effect of water absorption was investigated in-vitro by ageing PMMA-based bone cement samples for different periods up to 56 days in both Ringer's solution (37 °C) and air (37 °C and 30% humidity). Subsequently, the TG and Vicat softening temperatures of the samples were determined by differential scanning calorimetry and Vicat tests, respectively, according to prescribed methods. Over the entire ageing period, i.e. comparing one day of ageing in air and 56 days in Ringer's solution, the Vicat softening temperature dropped by 16 °C, while the TG dropped by 10 °C for Palacos® R PMMA-based bone cement. Water absorption over time correlated significantly with the Vicat softening temperature until saturation of the PMMA-based bone cement was reached. Based on the TG and Vicat softening temperature measurements, it can be assumed that in body-aged bone cement, an optimal softening can be achieved within a temperature range of 85 °C-93 °C to loosen the bond between the PMMA-based bone cement mantle and the prosthesis stem. These findings may pave the way for a gentler removal of the implant in revision THA.

Effect of Sodium Bicarbonate Ringer's Solution on Intraoperative Blood Gas Analysis and Postoperative Recovery Time in Liver Transplantation: A Single-Center Retrospective Study.

BACKGROUND Sodium bicarbonate Ringer's solution (BRS) is the latest generation of balanced crystal solutions. BRS does not increase the liver burden, but its impact in liver transplantation is unclear. The aim of this study was to investigate the effect of BRS as a fluid therapy on intraoperative blood gas analysis and postoperative recovery time in orthotopic liver transplantation (LT) patients. MATERIAL AND METHODS The study included 101 patients who received classical in situ liver transplantation at the Second Affiliated Hospital of Guangxi Medical University from November 2019 to January 2022. The patients were divided into 2 groups according to the intraoperative fluid infusion: the BRS group and the sodium lactate Ringer's solution group (LRS group). Intraoperative blood gas analysis, including pH, base excess (BE), bicarbonate, and lactic acid levels of radial artery blood, were collected after induction (T0), 30 min before opening (T1), 30 min after no liver period (T2), 30 min after opening (T3), and at the end of the operation (T4). Postoperative ICU catheter time, ICU stay time, and total hospitalization days were also recorded and compared between the 2 groups. RESULTS Lactic acid levels were decreased significantly at T3 in the BRS group (P<0.05). ICU catheter time, ICU hospitalization days, and total hospitalization days were significantly shorter in the BRS group (P<0.05). CONCLUSIONS BRS can decrease the lactic acid level at 30 min after opening, reducing the postoperative recovery time. BRS is more effective than LRS in liver transplantation.

Cancer-specific cytotoxicity of Ringer's acetate solution irradiated by cold atmospheric pressure plasma.

Cold atmospheric pressure plasmas are promising medical tools that can assist in cancer treatment. While the medical pathology mechanism is substantially understood, knowledge of the contribution of reactive species formed in plasma and the mode of activation of biochemical pathways is insufficient. Herein, we present a concept involving antitumoral plasma-activated organics, which is envisaged to increase cytotoxicity levels against cancer cells. Ringer's acetate solution was irradiated by low-temperature plasma at atmospheric pressure and possible reaction pathways of the compound generation are presented. The chemical compounds formed by plasma treatment and their effects on non-tumorigenic breast epithelial cells (MCF-10A) and breast cancer cells (MCF-7) were investigated. The cell viability results have shown that plasma-derived compounds have both, stimulatory and inhibitory effects on cell viability, depending on the concentration of the generated compounds in the irradiated liquids. Previous studies have shown that oxidative stresses involving reactive oxygen and nitrogen species (RONS) can be used to kill cancer cells. Hence, while RONS offers promising first-step killing effects, cell viability results have shown that plasma-derived compounds, such as acetic anhydride and ethyl acetate, have the potential to play important roles in plasma-based cancer therapy.

Albumin Infusion and Blood Loss After Cardiac Surgery.

BACKGROUND: In the recent ALBICS (ALBumin In Cardiac Surgery) trial, 4% albumin used for cardiopulmonary bypass priming and volume replacement increased perioperative bleeding compared with Ringer acetate. In the present exploratory study, albumin-related bleeding was further characterized. METHODS: Ringer acetate and 4% albumin were compared in a randomized, double-blinded fashion in 1386 on-pump adult cardiac surgery patients. The study end points for bleeding were the Universal Definition of Perioperative Bleeding (UDPB) class and its components. RESULTS: The UDPB bleeding grades were higher in the albumin group than the Ringer group: "insignificant" (albumin vs Ringer: 47.5% vs 62.9%), "mild" (12.7% vs 8.9%), "moderate" (28.7% vs 24.4%), "severe" (10.2% vs 3.2%), and "massive" (0.9% vs. 0.6%; P < .001). Patients in the albumin group received red blood cells (45.2% vs 31.5%; odds ratio [OR], 1.80; 95% CI, 1.44-2.24; P < .001), platelets (33.3% vs 21.8%; OR, 1.79; 95% CI, 1.41-2.28; P < .001), and fibrinogen (5.6% vs 2.6%; OR, 2.24; 95% CI, 1.27-3.95; P < .05), and underwent resternotomy (5.3% vs 1.9%; OR, 2.95; 95% CI, 1.55-5.60, P < .001) more often than patients in the Ringer group. The strongest predictors of bleeding were albumin group allocation (OR, 2.18; 95% CI, 1.74-2.74) and complex (OR, 2.61; 95% CI, 2.02-3.37) and urgent surgery (OR, 1.63; 95% CI, 1.26-2.13). In interaction analysis, the effect of albumin on the risk of bleeding was stronger in patients on preoperative acetylsalicylic acid. CONCLUSIONS: Perioperative administration of albumin, compared with Ringer's acetate, resulted in increased blood loss and higher UDBP class. The magnitude of this effect was similar to the complexity and urgency of the surgery.

Short-term effects of α-melanocyte-stimulating hormone in three distinct melanin-pigmented cell types of Anura.

Ectothermic animals present melanin-containing cells in their integument and viscera. Besides cutaneous melanophores, amphibians have melanomacrophages in the hepatic parenchyma and melanocytes in the viscera, which are also present in their testicular stroma. The native melanocyte stimulating hormone (α-MSH) is the main hormone that modulates the color change in melanophores. However, we still know too little about how the α-MSH acts in vivo on visceral melanin-containing cells. In this study, we collected 30 adult males of Physalaemus nattereri (Anura, Leptodactylidae) to evaluate the short-term effects of α-MSH on melanophores, melanocytes and melanomacrophages under light microscopy. For this, we injected 0.05 ml of a single intraperitoneal dose containing 2.5x10-7 mmol/10g of α-MSH, diluted in ringer solution, in five experimental groups with five individuals each one. The different groups were analyzed after 1, 3, 6, 12 and 24h. The control group with five other individuals received only 0.05 ml of ringer solution. The skin pigmentation increased quickly after animals received the hormone α-MSH with the consequent darkening of the body (body darkness). Melanophores, melanocytes and melanomacrophages responded similarly to the test, with an increase in the area containing melanin. However, melanophores and melanomacrophages reached their darkest pigmentation in a shorter period of time in comparison to the testicular melanocytes, probably due to specific metabolic characteristics of each organ. Thus, we verified that the three types of cells, although present in different organs, are responsive to the native hormone α-MSH, which enables us to treat them as a pigmentary system.