Hartmann's Solution Research Articles

Pulse oximetry-based perfusion index as a non-invasive indicator of systemic hemodynamics during spinal anesthesia in cesarean delivery

Background & Objectives: Placental perfusion is not autoregulated and is susceptible to effects of spinal anesthesia (SA) induced hypotension. The perfusion index (PI) is a non-invasive marker of peripheral vascular tone, and a higher PI indicates increased risk of hypotension following SA. This study aims to establish preoperative baseline PI in our local population and its correlation with incidence of intraoperative hypotension. Methods: This prospective observational study recruited 35 parturients who underwent elective lower segment cesarean section (LSCS). Preoperatively, baseline heart rate (HR), systolic blood pressure (SBP), mean arterial pressure (MAP) and PI were documented. SA was performed with 8 to 10 mg of injection bupivacaine 0.5% (hyperbaric) at L3–L4 interspace followed by co-loading with 1 L Hartmann solution. Hypotension was defined as SBP less than 80% of baseline or less than 90 mmHg. A bolus of phenylephrine 50 µg was given as rescue medication to treat the hypotension. Intraoperatively, degree of decrease in SBP, MAP and HR, as well as the amount of phenylephrine required was recorded every minute until delivery of the baby and 3 min thereafter. Results: The correlations between parturients’ baseline PI with the degree of decreases in systolic and mean arterial pressure (r = 0.81, P < 0.001 and r = 0.76, P < 0.001, respectively) and phenylephrine requirement (r = 0.761, p < 0.005) were recorded. This study identified that the patients with cut-off PI value of 3.2 were at higher risk for SA induced hypotension with a sensitivity of 85.9% and a specificity of 87.5% (P = 0.001). Conclusion: The patients with baseline cut-off perfusion index value of more than 3.2 were at higher risk for spinal anesthesia induced hypotension in elective cesarean section. Abbreviations: CO - cardiac output; LSCS - lower segment cesarean section MAP - mean arterial pressure; PI - perfusion index; SA - spinal anesthesia Keywords: Hypotension; Pulse Oximeter; Perfusion Index; Spinal Anesthesia; Cesarean section; Citation: Manap NSA, Zaini RHM, Shukeri WFWM, Omar SC, Abu Bakar MZ, Seevaunnamtum P. Pulse oximetry-based perfusion index as a non-invasive indicator of systemic hemodynamics during spinal anesthesia in cesarean delivery. Anaesth. pain intensive care 2024;28(5):927−932; DOI: 10.35975/apic.v28i5.2570 Received: July 23, 2024; Reviewed: September 02, 2024; Accepted: September 10, 2024

A double-blinded randomised controlled study of fluid restriction versus liberal fluid during induction of labour: A pilot study.

Excess intravenous fluid for women requiring an induction of labour may adversely affect the duration of labour and maternal/neonatal outcomes. This study aimed to determine the difference in duration of labour and outcomes with a low background infusion rate, compared to liberal background intravenous fluid management. A double blind randomised controlled pilot study was performed on 200 women who underwent induction of labour at a single institution. Women were randomised to an intravenous rate of 40 mL/h versus 250 mL/h of Hartmann's solution. Fluid boluses were strictly controlled to limit bias. This trial was registered with the Australian clinical trial registry: ACTRN12621001298808. Analysis of the total amount of fluid received showed good separation with Group 1 (40 mL/h) receiving 1,736 mL less than Group 2 (250 mL/h), median (interquartile range) 841 mL (458, 1691) versus 2,577 mL (1620, 4326) (P < 0.001). Median duration of labour was shorter in Group 1 by 24 min (P = ns). Subset analysis of nulliparous women showed that duration of labour was shorter in Group 1 by 83.5 min (P = ns). As this was a pilot study, a significant difference in duration of labour or secondary outcomes was not seen. Given the increasing numbers of nulliparous women having an induction of labour, potential for adverse maternal and neonatal outcomes and the associated higher rate of operative birth, this study guides power calculations and supports proof of concept for future research into optimum fluid management during induction of labour for these women.

Harmonising IV Oxycodone with Paediatric Perioperative Medications: A Compatibility Study Through Y-Type Connectors.

Co-administering multiple intravenous (IV) agents via Y-connectors is a common practice in hospitalised and fasting surgical patients. However, there is a lack of reliable data confirming the physical compatibility of some combinations including IV oxycodone, a drug that is gaining increasing popularity in the perioperative period. Concern regarding physical drug incompatibilities precludes concurrent coadministration with other common drugs through a single lumen. This can result in the cessation of infusions to allow the administration of other medications, resulting in exacerbation of acute pain. This study aims to evaluate the physical compatibility of IV oxycodone with some commonly co-administered drugs and IV fluids. Mixtures of oxycodone (1mg.mL-1) and the tested drugs and IV fluids were prepared in a ratio of 1:1. The mixtures were examined at 0 and 60 minutes from mixing and assessed using the European Conference Consensus Standards. This involved visual inspection (precipitation, turbidity, colour change, gas formation), spectrophotometry, and pH change. The tested drugs included ketamine, tramadol, clonidine, vancomycin, piperacillin/tazobactam, dexmedetomidine, cefotaxime, gentamicin, and paracetamol. In addition, the commonly used IV fluids tested included glucose 5% + sodium chloride 0.9% + 60 mmol potassium chloride, plasmalyte + dextrose 5%;plasmalyte + dextrose 5% + 55 mmol potassium chloride, plasmalyte + dextrose 5% + 55mmol potassium acetate, plasmalyte + dextrose 5% + 55mmol potassium dihydrogen phosphate, Hartmann's solution, Standard pediatric Total Parenteral Nutrition (TPN) 20/100 and TPN 25/150. IV oxycodone (1 mg.mL-1) showed no visual changes; no spectrophotometric absorption variability at 350, 410, or 550nm; and no pH changes of >0.5 at 0 or 60 minutes with any of the tested drugs or fluids in the concentrations tested. According to European Consensus Conference Standards, IV Oxycodone at 1 mg.mL-1 is physically compatible in a ratio of 1:1 v/v with all investigated drugs and fluids tested for at least 60 minutes.

Crystalloid Fluid Management of Non-Traumatic Hypotension by New South Wales Ambulance

Introduction Shock is circulatory insufficiency, inadequate oxygen delivery, and cellular hypoxia. Intravenous fluids are essential for shock management. Despite treatment, patients can face persistent shock with ongoing hypotension, contributing to higher mortality. This analysis aims to quantify hypotensive non-traumatic cases in an Australian ambulance service, determine persistent hypotension prevalence, and assess paramedic-administered intravascular fluids’ impact on blood pressure changes. Methods This study is a retrospective analysis of prehospital fluid resuscitation by New South Wales Ambulance paramedics during 2022. Hypotension is defined as a systolic blood pressure of ≤ 90 mmHg, and persistent hypotension is a systolic blood pressure consistently below 90 mmHg across all observations, with a final blood pressure below 90 mmHg. This study aimed to determine the volume of fluid resuscitation at which a plateau in population-level systolic blood pressure response is observed, by calculating the derivative of the fitted logistic regression model. Moreover, this analysis identified the relative contribution of factors influencing the probability of an attempt at intravenous or intraosseous access using machine learning. Results Among 796,865 attendances, 23,049 (2.9%) involved non-traumatic patients with hypotension. In total 7,388 (32.1%) of the hypotensive cases resulted in persistent hypotension, of which 3,235 (43.8%) received Hartmann’s solution and 1,745 (53.9%) received at least 500 ml of fluids but still had hypotension. The model showed that systolic blood pressure tends to stop increasing after 500–600 milliliters of fluid are given. This suggests that, on average, giving more fluid than this may not raise blood pressure further in a prehospital setting, though individual patient needs can differ. The top four factors from the machine learning shows that as initial respiratory rate goes up, the probability of intravascular access rises. Transport times less than 20 min are associated with a smaller chance of access and younger patients are less likely to receive an attempt. Finally, extremes of systolic blood pressure are more likely to receive access attempts. Conclusion This study found that three percent of non-traumatic attendances have at least one episode of hypotension, and that more than half of these have persistent hypotension. Only 44% of persistently hypotensive received fluids, and half of persistently hypotensive patients stayed hypotensive despite a reasonable volume of prehospital crystalloids.

Electrical bioimpedance analysis and comparison in biological tissues through crystalloid solutions implementation

Electrical bioimpedance is a non-invasive and radiation-free technique that was proposed to be used in different clinical areas, however, its practical use is limited due to its low capacity to discriminate between tissues. In order to overcome this limitation, our research group proposes to incorporate the contrast media into the electrical bioimpedance procedure. The main objective of the present study was to assess the crystalloid solutions as a possible contrast media to discriminate between different tissue types in the bioimpedance technique. Two medical-grade crystalloid solutions (Hartmann and NaCl 0.9%) were injected into three biological ex vivo models: kidney, liver, and brain. BIOPAC system was used to acquire bioimpedance data before and after the injections. The data was adjusted to the Debye electrical model. The analysis of measured values showed substantial bioimpedance disparities in tissues subjected to isotonic solutions. The NaCl solution exhibited more pronounced changes in electrical parameters compared to the Hartmann solution. Similarly, NaCl solution displayed superior discriminatory capabilities among tissues, with variations of 465%, 157%, and 206%. Distinct spectral modifications were identified, with tissues demonstrating unique responses at each frequency of analysis relative to untreated tissue. Variations in bandwidth alterations were discernible among tissues, providing clear distinctions. In conclusion, the research showed that the crystalloid solution exhibited greater sensitivity and superior tissue contrast at specific frequencies. This study's findings underscore the feasibility of implementing crystalloid solutions to enhance tissue discrimination, similar to the effects of contrast agents.

Tribological Evaluation of [β- TCP/HA]n Multilayer Coatings Immersed in Biological Fluids

Biomedical or surgical devices undergo numerous bone structure modification processes, which require enhanced tribo-mechanical properties in biological fluid environments to avoid corrosive processes. Therefore, the following research shows a detailed study of the tribological response of [β-TCP/HA]n multilayer coatings deposited on AISI 302 steels, in order to simulate biomedical devices subjected to friction processes in biological fluid. Mechanical study determined that the coating with 50 bilayers showed an increase 26.3% in elastic modulus of and 107.7% in hardness compared to the coating with 1 bilayer. Subsequently, the tribological evaluation in a dry and biological fluid environment (Hartmann's solution) showed a reduction in the friction coefficient of 36.7% and 43.5%, respectively, when comparing the n = 50 bilayers with the n = 1 bilayer. This study concludes that a coating with n = 50 bilayers is superior to n = 1 bilayer when used as a protective coating on biomedical devices.

Use of Albumin as a Resuscitative Fluid in the Intensive Care Unit.

Use of Albumin as a Resuscitative Fluid in the Intensive Care Unit.

Effect of prehydration solution on hearing threshold after chemotherapy in patients with head and neck cancers: a retrospective study.

The study aimed to evaluate the effect of prehydration solution on hearing thresholds after cisplatin chemotherapy. In this retrospective cohort study, we reviewed the data of patients who underwent ≥3 courses of cisplatin-based chemotherapy for locally advanced head and neck cancers at a tertiary referral center (n=64). The dextrose solution (DW) group (n=26) received 2 L of normal saline and 1 L of 5% dextrose. The Hartmann solution (HS) group (n=38) received 2 L of normal saline and 1 L of HS. Hearing data were measured 1 day before starting the first course of chemotherapy, and again 20 days after the first, second, and third courses of chemotherapy. The severity of hearing loss was evaluated using the Common Terminology Criteria for Adverse Events (CTCAE). Thresholds at all frequencies after chemotherapy were greater in the DW group than in the HS group. The increase in thresholds in 1 to 4 kHz after the third course of chemotherapy was greater in the DW group than in the HS group. CTCAE grades after the second and third courses of chemotherapy were greater in the DW group than in the HS group. Logistic regression showed that the odds ratio for CTCAE grade 3 or 4 after the third course of chemotherapy in the DW group was 4.84 on univariate analysis. Prehydration using a solution with salt was associated with a decrease in change in hearing thresholds after cisplatin chemotherapy in patients with head and neck cancers.

Effect of perioperative fluid volume restriction on the incidence of complications following pancreaticoduodenectomy.

Perioperative fluid restriction has been suggested to reduce morbidity and length of stay. The purpose of this study was to compare the morbidity following pancreaticoduodenectomy (PD) between fluid restriction group and conventional management group. Seventy-two patients were enrolled for perioperative fluid restriction of PD. During the operation, main fluid was infused at a rate of less than 8mL/kg/hr. Until POD#3, 10% dextrose and Hartmann's solution were administered at rates of 40 mL/h and {(1.5*body weight) - 42} mL/h, respectively. The historical control group consisted of 139 patients. We compared the rates of major complication (Clavien-Dindo grade III to V) and clinically relevant postoperative pancreatic fistula (CR-POPF), length of hospital stays (LOS), amount of urine output, and the rate of acute kidney injury (AKI). The rates of major complication (19.0% versus 18.7%; p > 0.999), CR-POPF (15.5% versus 15.1%; p > 0.999), and LOS (19 days [range: 10-52] versus 19 days [range: 11-75]; p=0.514) were comparable in the study and the control group, respectively. Amount of urine output during the operation and from POD#1 to POD#3 was more than minimal amount (0.5mL/kg/hr) in the both groups. Incidence rate of AKI in the study group was not higher than the control group (Stage I: 1.7% versus 2.9%, p > 0.999; stage II: 0% versus 1.4%, p > 0.999). There was no decrease in incidence of morbidity including POPF following PD with perioperative fluid restriction. Fluid restriction was feasible because it did not reduce urine output and did not increase incidence of AKI.

Stability of dilutions of methadone alone, and in combination with lidocaine and ketamine.

To assess stability and degradation over time, of methadone alone, and mixed with lidocaine and ketamine, using various diluents and storage conditions. Solutions of methadone diluted in 0.9% NaCl, and methadone-lidocaine-ketamine diluted in 0.9% NaCl or Hartmann's solution, and stored at room temperature with exposure to light, or refrigerated at 4°C and protected from light, were maintained over 10 days. Chemical stability was determined using liquid chromatography immediately after preparation and following 4, 24, 48, 96 and 240 hours of storage. Physical stability of the solutions was evaluated by visual examination and absorbance of ultraviolet/visible light. A linear model assessed the impact of different diluent solutions and storage conditions on drug degradation over time. There was no evidence of physicochemical incompatibility for any solution. Methadone concentration, when diluted alone or in methadone-lidocaine-ketamine with Hartmann's solution at 4°C, did not decline over time. Ketamine and lidocaine decreased to a similar extent over time, regardless of the diluent used or storage method, while methadone in methadone-lidocaine-ketamine diluted with 0.9% NaCl or with Hartmann's solution at room temperature exposed to light, also declined over time; however, all three methadone-lidocaine-ketamine components retained acceptable stability (<10%degradation) for at least 48 hours following preparation, irrespective of diluent or storage conditions. Regardless of the diluent or storage method, methadone-lidocaine-ketamine solutions degrade over time, but this only becomes clinically significant after 48 hours. Solutions of 1mg/ml methadone in 0.9% NaCl are stable for at least 10 days under storage conditions likely to be encountered in general practice.

The Effects of Intravenous Fluid Viscosity on the Accuracy of Intravenous Infusion Flow Regulators.

Intravenous infusion flow regulators (IIFRs) are widely used devices but it is unknown how much the difference between the IIFR scale and the actual flow rate depends on the viscosity of the intravenous (IV) fluid. This study evaluated the effects of viscosity on the flow rate of five IV fluids (0.9% normal saline, Hartmann’s solution, plasma solution-A, 6% hetastarch, and 5% albumin) when using IIFRs. The viscosity of crystalloids was 1.07–1.12 mPa·s, and the viscosities of 6% hetastarch and 5% albumin were 2.59 times and 1.74 times that of normal saline, respectively. When the IIFR scales were preset to 20, 100, and 250 mL/hr, crystalloids were delivered at the preset flow rate within a difference of less than 10%, while 6% hetastarch was delivered at approximately 40% of the preset flow rates and 5% albumin was approximately 80% transmitted. When delivering colloids, IIFRs should be used with caution.

Effects of the Administration of Different Buffered Balanced Crystalloid Solutions on Acid–Base and Electrolyte Status in Dogs with Gastric Dilation–Volvulus Syndrome: A Randomized Clinical Trial

ObjectiveTo investigate the effect of three different buffered balanced crystalloid solutions on acid–base status and electrolyte concentrations in dogs with gastric dilation–volvulus (GDV) syndrome. MethodsThe study design was a prospective, randomized clinical trial of 40 dogs. The dogs were randomly assigned to one of three groups according to the fluid used: Hartmann's solution (H), Plasmalyte (PL), and Ringerfundin (RF). Hemoglobin, albumin, lactate, electrolyte, and acid–base parameters were determined before fluid administration (T0) and at the end of surgery (T1). Results were assessed by one-way ANOVA, Fisher's exact test, the Wilcoxon signed-rank test, the Kruskal–Wallis test, and a linear mixed-effect regression model. A significance level of 0.05 was used in all analyses. ResultsBicarbonate and base excess (BE) levels increased and chloride concentration decreased in the PL group; in contrast, strong ion difference apparent (SIDapp) decreased and chloride concentration increased in the RF group. The mixed-effect model confirmed a significant interaction between the type of solution and time on the changes in bicarbonate, BE, anion gap (AG), SIDapp, and chloride levels. Clinical significanceSignificantly different effects in acid–base parameters were observed in dogs after intravenous administration of H, PL, and RF. However, clinical significance of these changes is lacking, requiring further investigation in a larger randomized controlled clinical trial.

The effect of perioperative fluid volume restriction in postoperative complication of pancreaticoduodenectomy

Perioperative fluid restriction has been suggested to reduce morbidity and length of stay. However, there are few studies regarding fluid restriction of pancreato-biliary surgery. The purpose of this study was to compare the morbidity following PD between the fluid restriction group and conventional management group. Between September 2017 and October 2020, 72 patients were enrolled for perioperative fluid restriction of PD. During the operation, main fluid was injected at a rate of 6-8 mL/kg*hr. From the operation day to the day 3 postoperatively, 10% dextrose and Hartmann's solution were infused at a rate of 40 mL/hr and {(1.5*bwt)-42} mL/hr, respectively. Of 72 patients, 57 patients were finally analyzed in this study. The control group consisted of 139 patients who underwent PD from March 2013 to March 2016 and they were conventionally managed after the operation. We compared the postoperative morbidity, transfusion rate, length of hospital stays, amount of input and output, and serum creatinine level between the 2 groups. The rate of major morbidity defined as any complication from grade III to V on the Clavien-Dindo scale in the study group was not significantly higher than that in the control group (19.3% vs. 18.7%; p = 1.0). There were no differences in the rate of clinically relevant postoperative pancreatic fistula (CR-POPF) between both groups (15.8% vs. 12.9%; p = 0.65). No significant differences were also present in transfusion rate, operation time and length of hospital stay. Perioperative fluid restriction did not affect incidence of major morbidity, especially CR-POPF following PD.

Comparison of Balanced Crystalloid Solutions: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

To summarize the evidence comparing various balanced crystalloid solutions. We searched MEDLINE, EMBASE, PUBMED, and CENTRAL databases. We included randomized controlled trials that directly compared the IV administration of one balanced crystalloid solution with another. We examined metabolic and patient-important outcomes and conducted meta-analysis using random effects model. For comparisons or outcomes with insufficient data to allow for pooling, we describe results narratively. We assessed risk of bias for individual trials using the Cochrane risk of bias tool and certainty of evidence using Grading of Recommendations, Assessment, Development and Evaluations methodology. We included 24 randomized controlled trials comparing Plasmalyte, Ringer's Lactate, Ringerfundin, Hartmann's solution, Ringer's Bicarbonate, Sterofundin, Kabilyte, Normosol, and novel balanced solutions. Of the included studies, 16 were performed in the perioperative setting, six in the ICU, one in the emergency department, and one in healthy volunteers. Administration of Plasmalyte resulted in a lower postinfusion serum chloride concentration (mean difference, 0.83 mmol/L lower; 95% CI, 0.03-1.64 mmol/L lower, low certainty), higher postinfusion base excess (mean difference, 0.65 mmol/L higher, 95% CI, 0.25-1.05 mmol/L higher, low certainty), and lower postinfusion serum lactate levels (mean difference, 0.46 mmol/L lower; 95% CI, 0.05-0.87 mmol/L lower, low certainty) compared with administration of any other balanced crystalloid. There were no important differences in postinfusion serum pH or potassium when comparing Plasmalyte with other balanced crystalloids. Data addressing other comparisons or examining the impact of different balanced crystalloids on patient-important outcomes were sparsely reported and too heterogeneous to allow for pooling. Administration of Plasmalyte results in lower serum concentrations of chloride and lactate, and higher base excess than other balanced crystalloids. The certainty of evidence is low and requires further study in large randomized controlled trials to inform the choice of balanced crystalloid in patients requiring volume replacement.

Prospective randomized controlled blinded clinical trial evaluating biomarkers of acute kidney injury following 6% hydroxyethyl starch 130/0.4 or Hartmann's solution in dogs.

To evaluate the effect of 6% hydroxyethyl starch (HES) 130/0.4, compared with a Hartmann's solution control (CRYST), on urine biomarkers of acute kidney injury (AKI) in dogs prescribed a fluid bolus. Randomized, controlled, blinded clinical trial January 2018 to February 2019. University teaching hospital. Forty client-owned dogs. Dogs prescribed a fluid bolus were randomized to receive at least 10mL/kg of HES or CRYST with clinicians and investigators blinded to fluid type. Study fluid was used for further boluses as required in the following 24hours, to a limit of 40mL/kg total, after which fluid administration was open-label. Urine was collected prior to and 6, 12, and 24hours after the first study fluid bolus. Urine concentrations of AKI biomarkers: neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, kidney injury molecule-1 (KIM), clusterin, and osteopontin were measured using a magnetic bead multiplexed assay. Osmolality-indexed biomarker concentrations were compared between groups over time with linear mixed-effects models, with P<0.05 considered significant. The mean volume of study fluid administered was not significantly different between groups (HES: 23.1mL/kg, CRYST: 25.9mL/kg; P=0.47, t-test). There were no significant differences between groups in change over time of osmolality-indexed urine concentrations of NGAL (P=0.91), cystatin C (P=0.95), KIM (P=0.77), clusterin (P=0.63), or osteopontin (P=0.91). The maximum Veterinary Acute Kidney Injury (VAKI) score up to 7 days during hospitalization (P=1.0) and in-hospital mortality (P=0.49) were not significantly different between groups, as compared by Fisher's exact test. There were no differences in change over time of urine AKI biomarkers in dogs treated with 10 - 40mL/kg HES or CRYST over 24hours. Larger clinical trials with patient-centered outcomes are required to investigate the safety of HES in dogs.

Reversal of the Pathophysiological Responses to Gram-Negative Sepsis by Megadose Vitamin C.

Oxidative stress appears to initiate organ failure in sepsis, justifying treatment with antioxidants such as vitamin C at megadoses. We have therefore investigated the safety and efficacy of megadose sodium ascorbate in sepsis. Interventional study. Research Institute. Adult Merino ewes. Sheep were instrumented with pulmonary and renal artery flow-probes, and laser-Doppler and oxygen-sensing probes in the kidney. Conscious sheep received an infusion of live Escherichia coli for 31 hours. At 23.5 hours of sepsis, sheep received fluid resuscitation (30 mL/kg, Hartmann solution) and were randomized to IV sodium ascorbate (0.5 g/kg over 0.5 hr + 0.5 g/kg/hr for 6.5 hr; n = 5) or vehicle (n = 5). Norepinephrine was titrated to restore mean arterial pressure to baseline values (~80 mm Hg). Sepsis-induced fever (41.4 ± 0.2°C; mean ± se), tachycardia (141 ± 2 beats/min), and a marked deterioration in clinical condition in all cases. Mean arterial pressure (86 ± 1 to 67 ± 2 mm Hg), arterial Po2 (102.1 ± 3.3 to 80.5 ± 3.4 mm Hg), and renal medullary tissue Po2 (41 ± 5 to 24 ± 2 mm Hg) decreased, and plasma creatinine doubled (71 ± 2 to 144 ± 15 µmol/L) (all p < 0.01). Direct observation indicated that in all animals, sodium ascorbate dramatically improved the clinical state, from malaise and lethargy to a responsive, alert state within 3 hours. Body temperature (39.3 ± 0.3°C), heart rate (99.7 ± 3 beats/min), and plasma creatinine (32.6 ± 5.8 µmol/L) all decreased. Arterial (96.5 ± 2.5 mm Hg) and renal medullary Po2 (48 ± 5 mm Hg) increased. The norepinephrine dose was decreased, to zero in four of five sheep, whereas mean arterial pressure increased (to 83 ± 2 mm Hg). We confirmed these physiologic findings in a coronavirus disease 2019 patient with shock by compassionate use of 60 g of sodium ascorbate over 7 hours. IV megadose sodium ascorbate reversed the pathophysiological and behavioral responses to Gram-negative sepsis without adverse side effects. Clinical studies are required to determine if such a dose has similar benefits in septic patients.

Does skin preparation alter suture strength characteristics? Assessing the effect of chlorhexidine and isopropyl alcohol on common skin closure suture material.

Sutures are essential to approximate tissues and enable healing by first intention until a wound regains its original tensile strength. The mechanical properties of sutures are well documented, but the effects of exposing sutures to skin preparation solutions used in surgery are not. This study was performed to investigate whether 2% chlorhexidine and 70% isopropyl alcohol skin preparation, commonly used prior to incision and prior to closure, has any effect on the mechanical properties of several commonly used surgical suture types. Four suture types were soaked in either 2% chlorhexidine and 70% isopropyl alcohol or Hartmann's solution for 5 minutes. All sutures were left to dry for 11 days before being tested to failure using an Instron 3367 tensile testing machine. Testing revealed significant differences in failure load, ultimate tensile stress, and Young's modulus between suture types (P < .05). No significant differences in failure load (P = .98), ultimate tensile stress (P = .21), or Young's modulus (P = .22) were observed between the test group and the control group when comparing sutures of the same type. This study demonstrates that chlorhexidine/isopropyl skin preparation solutions do not significantly change the mechanical properties of suture materials exposed to them.

Contemporary Australian priming constituents for adult perfusion centres: a survey.

Evidence for the ideal/best practice priming solution remains meagre and largely historical. The aim of this survey was to determine the constituents of contemporary priming solutions in adult open-heart centres across Australia. This would provide insight on the level of variation within current Australian priming practices and inform perfusionists of how their current priming methods compare to the spectrum of Australian practice. A total of 15 survey questions covering various aspects of priming constituents were sent via email to perfusionists in all 63 adult open-heart centres across Australia. This prime survey received a 100% response rate across Australia. All units prime with a balanced physiological solution, 73% of units prime with Plasma-Lyte 148 and 19% with Hartmann's solution. No synthetic colloids are used for priming in Australia. Up to 6,520 (30%) cases per annum receive heparin as the only additive to their prime base solution. All other cases had various combinations of sodium bicarbonate, mannitol and albumin added for a variety of recorded reasons. Contemporary Australian priming practices show a marked level of conformity between units. Variation exists in the rationale for adding sodium bicarbonate, mannitol and albumin. Further investigations into the clinical effects of these additives are required to determine if the rationale for their addition is historical or judicious in this contemporary era of low prime volumes, physiological base solutions and coated bypass circuits.

Evaluation of the caudal vena cava diameter to abdominal aortic diameter ratio and the caudal vena cava respiratory collapsibility for predicting fluid responsiveness in a heterogeneous population of hospitalized conscious dogs.

Fluid responsiveness, defined as the response of stroke volume to fluid loading, is a tool to individualize fluid administration in order to avoid the deleterious effects of hypovolemia or hypervolemia in hospitalized patients. To evaluate the accuracy of two ultrasound indices, the caudal vena cava to abdominal aorta ratio (CVC/Ao) and the respiratory collapsibility of the caudal vena cava (cCVC), as independent predictors of fluid responsiveness in a heterogeneous population of spontaneously breathing, conscious, hospitalized dogs. A prospective, multicenter, observational, cross-sectional study was designed in twenty-five dogs. The accuracy of CVC/Ao and cCVC in predicting fluid responsiveness was evaluated by the area under the receiver operating characteristic curve (AUROC) in a group of hospitalized dogs after receiving a mini-fluid bolus of 4 ml/kg of Hartmann’s solution. Dogs with an increased aortic velocity time integral >15% were classified as fluid responders. Twenty-two dogs were finally included. Ten were classified as responders and 12 as non-responders. The AUROC curves were 0.88 for the CVC/Ao ratio (95% confidence interval, CI, 0.67–0.98; P=0.0001) and 0.54 for cCVC (95% CI 0.32–0.75; P=0.75). The CVC/Ao threshold optimized for best sensitivity (SE) and specificity (SP) values was 0.83 (SE 100%; SP 75%). In spontaneously breathing hospitalized dogs, the CVC/Ao measurement predicted stroke volume increase after a fluid bolus, while the respiratory variations in the cCVC did not discriminate between fluid responders and non-responders.

Preoperative VolumE Replacement therapy in DIabetic patients undergoing coronary artery bypass grafting surgery: results from an open parallel group randomized Controlled Trial (VeRDiCT).

To investigate the effect of preoperative volume replacement therapy (VRT) on renal function, health outcome and time to fitness for discharge in diabetic patients undergoing coronary artery bypass grafting (CABG). In 2 parallel randomized controlled trials, diabetic patients were allocated to preoperative VRT (1 ml/kg/h of Hartmann's solution for 12 h) or usual care. Primary outcome was time to fitness for discharge. Secondary outcomes included acute kidney injury, postoperative complications, patient-reported quality of life (QoL), hospital resource use and markers of renal, cardiac and inflammatory injury. In total, 169 patients were randomized (84 VRT, 85 usual care; mean age 64 years; 88% male). Time to fitness for discharge was similar between groups [median 6 days; interquartile range 5.0-9.0 in both groups; hazard ratio 0.95, 95% confidence interval (CI) 0.65-1.38; P = 0.78]. Postoperative acute kidney injury was not statistically different (VRT: 27.7% vs usual care: 18.8%, odds ratio 1.72, 95% CI 0.82-3.59; P = 0.15). Estimated glomerular filtration rate (mean difference -0.92, 95% CI -4.18 to 2.25; P = 0.56), microalbumin/creatinine ratio [geometric mean ratio (GMR) 1.16, 95% CI 0.94-1.42; P = 0.16], N-acetyl-beta-d-glucosaminidase (GMR 1.08, 95% CI 0.83-1.40; P = 0.57), C-reactive protein (GMR 1.00, 95% CI 0.88-1.13; P = 0.94), troponin T (Trop-T; GMR 1.18, 95% CI 0.78-1.79; P = 0.39) and other secondary health outcomes were similar between groups. QoL improved in both groups at 3 months with no difference observed. The use of preoperative VRT is not superior to usual care in diabetic patients undergoing CABG. ISRCTN02159606.