Intravenous fluids: balancing solutions

Balanced Solution Versus Normal Saline in Predicted Severe Acute Pancreatitis: A Stepped Wedge Cluster Randomized Trial

OBJECTIVE

To compare the effect of balanced multielectrolyte solutions (BMESs) versus normal saline (NS) for intravenous fluid on chloride levels and clinical outcomes in patients with predicted severe acute pancreatitis (pSAP).

BACKGROUND

Isotonic crystalloids are recommended for initial fluid therapy in acute pancreatitis, but whether the use of BMES in preference to NS confers clinical benefits is unknown.

METHODS

In this multicenter, stepped-wedge, cluster-randomized trial, we enrolled patients with pSAP (acute physiology and chronic health evaluation II score ≥8 and C-reactive protein >150 mg/L) admitted within 72 hours of the advent of symptoms. The study sites were randomly assigned to staggered start dates for a one-way crossover from the NS phase (NS for intravenous fluid) to the BMES phase (sterofudin for intravenous fluid). The primary endpoint was the serum chloride concentration on trial day 3. Secondary endpoints included a composite of clinical and laboratory measures.

RESULTS

Overall, 259 patients were enrolled from 11 sites to receive NS (n = 147) or BMES (n = 112). On trial day 3, the mean chloride level was significantly lower in patients who received BMES [101.8 mmol/L (SD: 4.8) vs 105.8 mmol/L (SD: 5.9), difference -4.3 mmol/L (95% CI: -5.6 to -3.0 mmol/L) ; P < 0.001]. For secondary endpoints, patients who received BMES had less systemic inflammatory response syndrome (19/112, 17.0% vs 43/147, 29.3%, P = 0.024) and increased organ failure-free days [3.9 days (SD: 2.7) vs 3.5 days (SD: 2.7), P < 0.001] by trial day 7. They also spent more time alive and out of the intensive care unit [26.4 days (SD: 5.2) vs 25.0 days (SD: 6.4), P = 0.009] and hospital [19.8 days (SD: 6.1) vs 16.3 days (SD: 7.2), P < 0.001] by trial day 30.

CONCLUSIONS

Among patients with pSAP, using BMES in preference to NS resulted in a significantly more physiological serum chloride level, which was associated with multiple clinical benefits (Trial registration number: ChiCTR2100044432).

Intra-Articular Physiological Saline in Temporomandibular Disorders May Be a Treatment, Not a Placebo: A Hypothesis, Systematic Review, and Meta-Analysis

Background: Intra-articular injections reduce pain in patients with temporomandibular joint (TMJ) disorders who are unresponsive to conservative treatment. Hyaluronic acid, blood products, and medications provide rapid relief when administered this way, although their mechanisms of action remain unclear. In control groups, which are intended to be untreated, 0.9% NaCl is typically delivered. The hypothesis that "normal saline injections in TMJ cavities produce a therapeutic effect" is proposed, with an exploration of its potential verification, alongside a systematic review and meta-analysis of studies on intra-TMJ 0.9% NaCl. Methods: Randomized controlled trials (RCTs) on patients with TMJ internal derangement, arthritis, or degeneration were selected under PRISMA 2020 and assessed with RoB2. Results: Seven RCTs with 359 patients were included. Weekly follow-ups revealed a decrease in articular pain by 23.72% (SE: 0.84%; 95% CI: 24.38-21.06%; p < 0.01), and monthly follow-ups indicated a decrease of 34.01% (SE: 1.09%; 95% CI: 36.16-31.86%; p < 0.01) compared to the baseline values. These findings were grounded in low-risk-of-bias evidence on 267 patients in five RCTs and 222 patients in four RCTs, respectively. Conclusions: The hypothesis warrants further testing to determine whether, in addition to the known biological activity of typical injectables, the mechanical action also contributes to pain relief.

A Review on In Vivo Research Dehydration Models and Application of Rehydration Strategies

Background: Dehydration, a common condition where the amount water lost from the body exceeds intake, disrupts metabolic processes and negatively impacts health and performance. Rehydration, the process of restoring body fluids and electrolytes to normal levels, is crucial for maintaining physiological health. In vivo dehydration models are experimental systems used to study the effects of dehydration on living organisms. However, a comprehensive summary of in vivo models and the application of human rehydration strategies is lacking. Methods: This review provides a comprehensive overview of various in vivo models and rehydration strategies. Results: In vivo models, stimulated by fluid restriction, exercise, thermal exposure, and chemicals, have been used to study dehydration. Importantly, the principles, characteristics, and limitations of the in vivo models are also discussed, along with rehydration administration methods, including oral, intestinal, intravenous, subcutaneous, and intraperitoneal routes. Additionally, rehydration strategies and the application for managing different dehydration conditions both in daily life and clinical settings have been summarized. Conclusions: Overall, this review aims to enhance the understanding of the conditions in which in vivo dehydration models and rehydration strategies are applicable, thereby advancing research into the physiological and pathological mechanisms of dehydration and supporting the development of effective rehydration therapies.

Polycyclic aromatic hydrocarbon skin permeation efficiency in vitro is lower through human than pigskin and decreases with lipophilicity

Polycyclic aromatic hydrocarbons (PAH) are persistent environmental pollutants, which occasionally appear as contaminants in consumer products. Upon dermal contact, transfer of PAH into the stratum corneum (s.c.) and migration through the skin may occur, resulting in this class of highly toxic compounds to become bioavailable. In this study, dermal penetration through human and porcine skin of 24 PAH, comprising broad molar mass (M: 152-302 g/mol) and octanol-water partition coefficient (logP: 3.9-7.3) ranges, was evaluated via Franz diffusion cell in vitro assays. More lipophilic and potentially more toxic PAH had decreased permeation rates through the rather lipophilic s.c. into the more hydrophilic viable (epi-)dermis. Furthermore, human skin was less permeable than pigskin, a commonly used surrogate in skin penetration studies. In particular, the s.c. of human skin retains a greater share of PAH, an effect that is more pronounced for smaller PAH. Additionally, we compared the skin permeation kinetics of different PAH in pigskin. While small PAH (M < 230 g/mol, logP < 6) permeate the skin quickly and are detected in the receptor fluid after 2 h, large PAH (M > 252 g/mol, logP ≥ 6) do not fully permeate the skin up to 48 h. This indicates that highly lipophilic PAH do not become bioavailable as readily as their smaller congeners when transferred to the skin surface. Our data suggest that pigskin could be used as a surrogate for worst case scenario estimates of dermal PAH permeation through human skin.

Maintenance intravenous fluid therapy in infants with sepsis and hyponatremia: a clinical trial

BACKGROUND

This study aimed to compare the effect of two methods of maintenance intravenous fluid therapy on hyponatremia in hospitalized infants with sepsis.

METHODS

In a double-blinded randomized clinical trial, 60 term infants with sepsis were enrolled. Blood samples were taken to determine sodium, potassium, Creatinine, and BUN levels before the initiation of treatment. Urine samples were taken to assess specific gravity and urinary output. Infants in the intervention group received half saline in 10% dextrose and infants in the control group were assigned to receive the conventional solution as maintenance. The above indicators were re-evaluated 24 and 48 h after the initiation of treatment. Two groups were compared concerning the incidence of hyponatremia, and other criteria such as urinary output and urinary specific gravity, blood urea nitrogen (BUN), and creatinine levels.

RESULTS

Hyponatremia was more common in the control group. Sodium levels were significantly higher in half saline recipients 24 h (137.83 ± 2.86 vs. 134.37 ± 1.91 mmol/L), and 48 h (138.10 ± 2.41 vs. 133.66 ± 1.98 mmol/L) after treatment (P < 0.001). Although BUN in the intervention group was significantly higher in comparison to the control group, the difference in urinary output, urine specific gravity, potassium, and Creatinine levels were not significant in the two groups.

CONCLUSIONS

The use of a half-saline solution as maintenance fluid reduces the risk of hyponatremia after 48 h when compared to 0.18%NaCl.

TRIAL REGISTRATION

This has been registered at Iranian Registry of Clinical Trials (Retrospectively registered, Registration date: 2017-10-12, identifier: IRCT2017053034223N1, https://irct.behdasht.gov.ir/trial/26204 ).

2024 AAHA Fluid Therapy Guidelines for Dogs and Cats

Fluids are drugs used in veterinary patients capable of producing beneficial therapeutic or inadvertent harmful effects within the body's intravascular, interstitial, and intracellular fluid spaces. The individualized design of a fluid therapy plan requires careful patient assessment and targeted selection of proper fluid types, administration routes, and rates, along with adjustments during therapy tailored specifically as per the individual patient's fluid requirement and therapeutic response. Personalized fluid prescriptions and vigilant patient monitoring help avoid patient morbidity from body fluid deficiencies, fluid excess, and electrolyte derangements and support better patient outcomes. These guidelines provide an overview of fluid dynamics within the fluid spaces of the body, describe various types of fluids and their uses, and outline recommendations for fluid administration for resuscitation, rehydration, and maintenance purposes. The guidelines also outline approaches to fluid therapy for anesthetized patients and reiterate the recommendations of reduced fluid rates in this population of patients. Additionally, the guidelines include practical fluid therapy strategies for patients with various common disorders. The goal of these guidelines is to help veterinary professionals safely and effectively prescribe and administer fluid therapy for canine and feline patients.

Update on perioperative fluids

Adequate fluid management in the perioperative period in paediatric patients is essential for restoring and maintaining homeostasis and ensuring adequate tissue perfusion. A well-designed infusion regimen is crucial for preventing severe complications such as hyponatraemic encephalopathies. The composition of perioperative fluid solutions is now guided by an understanding of extracellular fluid physiology. Various crystalloid and colloidal products are available for use, but a comprehensive approach requires careful consideration of their drawbacks and limitations. Additionally, the unique characteristics of different patient groups must be taken into account. This review will provide the reader with physiological considerations for perioperative fluids and describe indications for perioperative intravenous fluid therapy in paediatric patients. The current evidence on perioperative fluid therapy is finally summarised in practical recommendations.

Intravenous fluid rate of 250 mL/h versus 125 mL/h in nulliparous women: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Evidence regarding the type and rate of intravenous (IV) fluid administration during labor is still inconclusive and the studies assessing the impact of IV fluids had mixed results.

OBJECTIVES

To evaluate the effects of IV fluids at an infusion rate of 250 mL/h as compared with 125 mL/h on labor outcomes in nulliparous women.

SEARCH STRATEGY

We searched six databases for relevant studies through a search strategy containing the relevant keywords "IV hydration", "IV fluids", and "labor" from the inception of these databases to May 1, 2023, without any applied restrictions.

SELECTION CRITERIA

Search results were imported to Covidence for screening of eligible articles for this review. Randomized controlled trials (RCTs) assessing the impact of IV fluids at 250 mL/h on the outcomes of labor in nulliparous women at term (>37 weeks) as compared with 125 mL/h were included only.

DATA COLLECTION AND ANALYSIS

Data regarding the characteristics of included studies, participant's baseline characteristics, and concerned outcomes were collected in an Excel spreadsheet and all the concerned outcomes were pooled as risk ratios (RR) or mean difference (MD) with 95% confidence interval (CI) in the meta-analysis models using RevMan 5.4.

MAIN RESULTS

Pooled data from 11 RCTs with 1815 patients showed that 250 mL/h infusion rate had a significant reduction in cesarean section rate (RR 0.70, 95% CI 0.56-0.88, P = 0.002), the first stage of labor duration (MD -46.97, 95% CI -81.79 to -12.14, P = 0.008), the second stage of labor duration (MD -2.69, 95% CI -4.34 to -1.05, P = 0.001), prolonged labor incidence (RR 0.72, 95% CI 0.58-0.89, P = 0.003), as compared with 125 mL/h. Also, the vaginal delivery rate (RR 1.07, 95% CI 1.02-1.12, P = 0.009) was higher with a 250 mL/h infusion rate.

CONCLUSION

IV fluids at an infusion rate of 250 mL/h during labor in nulliparous women decreased the cesarean delivery rate, increased the vaginal delivery rate, shortened the first and second-stage labor duration, decreased the incidence of prolonged labor as compared with 125 mL/h. These findings suggest enhanced labor progression and a lower risk of labor complications with higher infusion rates. However, future research involving a more diverse population and exploring the potential benefits of combining IV infusion rates with other interventions, such as adding dextrose or less restrictive oral intake during labor, is needed.

Impact of the Design of Different Infusion Containers on the Dosing Accuracy of a Therapeutic Drug Product

Residual volumes of infusion solutions vary greatly due to container and dimensional variances. Manufacturers use overfill to compensate, but the exact amounts vary significantly. This variability in overfill - when carrier solutions are used to dilute other parenteral preparations - may lead to variable concentrations and dosing, hence, potential risk for patients. We analyzed the overfill and residual volume of 22 pre-filled infusion containers and evaluated the impact on the (simulated) dosing accuracy of a therapeutic drug product for different handling scenarios. In addition, compendial properties of the diluents (i.e. sub-visible particles, pH, color and opalescence) were assessed. The overfill and residual volume between different containers for the same diluent varied. As container size increased, the relative volume of overfill decreased while the residual volume remained constant. The design and material of the containers (e.g. port systems) defined the residual volume. Different handling scenarios led to differences in dosing accuracy. As a result, no universal approach applicable for all containers can be defined. To ensure the right dose, it is recommended to pre-select the preferred diluent, evaluate fill volumes of carrier solutions, and assess in-use compatibility of the product solution with its diluent in terms of concentration and volume.

The effect of dehydration, hyperchloremia and volume of fluid resuscitation on acute kidney injury in children admitted to hospital with diabetic ketoacidosis

BACKGROUND

Acute kidney injury (AKI) is a recognized comorbidity in pediatric diabetic ketoacidosis (DKA), although the exact etiology is unclear. The unique physiology of DKA makes dehydration assessments challenging, and these patients potentially receive excessive amounts of intravenous fluids (IVF). We hypothesized that dehydration is over-estimated in pediatric DKA, leading to over-administration of IVF and hyperchloremia that worsens AKI.

METHODS

Retrospective cohort of all DKA inpatients at a tertiary pediatric hospital from 2014 to 2019. A total of 145 children were included; reasons for exclusion were pre-existing kidney disease or incomplete medical records. AKI was determined by change in creatinine during admission, and comparison to a calculated baseline value. Linear regression multivariable analysis was used to identify factors associated with AKI. True dehydration was calculated from patients' change in weight, as previously validated. Fluid over-resuscitation was defined as total fluids given above the true dehydration.

RESULTS

A total of 19% of patients met KDIGO serum creatinine criteria for AKI on admission. Only 2% had AKI on hospital discharge. True dehydration and high serum urea levels were associated with high serum creatinine levels on admission (p = 0.042; p < 0.001, respectively). Fluid over-resuscitation and hyperchloremia were associated with delayed kidney recovery (p < 0.001). Severity of initial AKI was associated with cerebral edema (p = 0.018).

CONCLUSIONS

Dehydration was associated with initial AKI in children with DKA. Persistent AKI and delay to recovery was associated with hyperchloremia and over-resuscitation with IVF, potentially modifiable clinical variables for earlier AKI recovery and reduction in long-term morbidity. This highlights the need to re-address fluid protocols in pediatric DKA.

A Comprehensive Review of Chloride Management in Critically Ill Patients

Chloride, often overshadowed in electrolyte management, emerges as a crucial player in the physiological intricacies of critically ill patients. This comprehensive review explores the multifaceted aspects of chloride, ranging from its significance in cellular homeostasis to the consequences of dysregulation in critically ill patients. The pathophysiology of hyperchloremia and hypochloremia is dissected, highlighting their intricate impact on acid-base balance, renal function, and cardiovascular stability. Clinical assessment strategies, including laboratory measurements and integration with other electrolytes, lay the foundation for targeted interventions. Consequences of dysregulated chloride levels underscore the need for meticulous management, leading to an exploration of emerging therapies and interventions. Fluid resuscitation protocols, the choice between crystalloids and colloids, the role of balanced solutions, and individualized patient approaches comprise the core strategies in chloride management. Practical considerations, such as monitoring and surveillance, overcoming implementation challenges, and embracing a multidisciplinary approach, are pivotal in translating theoretical knowledge into effective clinical practice. As we envision the future, potential impacts on critical care guidelines prompt reflections on integrating novel therapies, individualized approaches, and continuous monitoring practices. In conclusion, this review synthesizes current knowledge, addresses practical considerations, and envisions future directions in chloride management for critically ill patients. By embracing a holistic understanding, clinicians can navigate the complexities of chloride balance, optimize patient outcomes, and contribute to the evolving landscape of critical care medicine.

Pediatric perioperative fluid management

The purpose of perioperative fluid management in children is to maintain adequate volume status, electrolyte level, and endocrine system homeostasis during the perioperative period. Although hypotonic solutions containing glucose have traditionally been used as pediatric maintenance fluids, recent studies have shown that isotonic balanced crystalloid solutions lower the risk of hyponatremia and metabolic acidosis perioperatively. Isotonic balanced solutions have been found to exhibit safer and more physiologically appropriate characteristics for perioperative fluid maintenance and replacement. Additionally, adding 1-2.5% glucose to the maintenance fluid can help prevent children from developing hypoglycemia as well as lipid mobilization, ketosis, and hyperglycemia. The fasting time should be as short as possible without compromising safety; recent guidelines have recommended that the duration of clear fluid fasting be reduced to 1 h. The ongoing loss of fluid and blood as well as the free water retention induced by antidiuretic hormone secretion are unique characteristics of postoperative fluid management that must be considered. Reducing the infusion rate of the isotonic balanced solution may be necessary to avoid dilutional hyponatremia during the postoperative period. In summary, perioperative fluid management in pediatric patients requires careful attention because of the limited reserve capacity in this population. Isotonic balanced solutions appear to be the safest and most beneficial choice for most pediatric patients, considering their physiology and safety concerns.

Balanced crystalloid solutions versus normal saline in intensive care units: a systematic review and meta-analysis

BACKGROUND

Intravenous fluid therapy is important for pediatric and adult patients in intensive care units (ICUs). However, medical professionals continue to struggle to determine the most appropriate fluids to obtain the best possible outcomes for each patient.

OBJECTIVE

We conducted a meta-analysis involving cohort studies and randomized controlled trials (RCTs) to compare the influence of balanced crystalloid solutions and normal saline among patients in ICUs.

PATIENTS AND METHODS

Studies that compared balanced crystalloid solutions and saline in ICU patients from databases including PubMed, Embase, Web of Science, and Cochrane Library were systematically searched up to July 25, 2022. The primary outcomes were mortality and renal-related outcomes, which included major adverse kidney events within 30 days (MAKE30), acute kidney injury (AKI), new receipt of renal replacement therapy (RRT), maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline. Service utilization including length of hospital stay, ICU stay, ICU-free days and ventilator-free days were also reported.

RESULTS

A total of 13 studies (10 RCTs and 3 cohort studies) involving 38,798 patients in ICUs met the selection criteria. Our analysis revealed that each subgroup had no significant difference in mortality outcomes among ICU patients between balanced crystalloid solutions and normal saline. A significant difference was detected between the adult groups (odds ratio [OR], 0.92; 95% confidence interval [CI], [0.86, 1.00]; p = 0.04) indicating that the AKI in the balanced crystalloid solutions group was lower than that in the normal saline group. Other renal-related outcomes, such as MAKE30, RRT, maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline showed no significant difference between the two groups. Regarding secondary outcomes, the balanced crystalloid solution group had a longer ICU stay time (WMD, 0.02; 95% CI, [0.01, 0.03]; p = 0.0004 and I2 = 0%; p = 0.96) than the normal saline group among adult patients. Furthermore, children treated with balanced crystalloid solution had a shorter hospital stay time (WMD, - 1.10; 95% CI, [- 2.10, - 0.10]; p = 0.03 and I2 = 17%; p = 0.30) than those treated with saline.

CONCLUSIONS

Compared with saline, balanced crystalloid solutions could not reduce the risk of mortality and renal-related outcomes, including MAKE30, RRT, maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline, but the solutions may reduce total AKI incidence among adult patients in ICUs. For service utilization outcomes, balanced crystalloid solutions were associated with a longer length of ICU stay in the adult group and shorter length of hospital stay in the pediatric group.

Normal saline: Past, present, and future

Normal saline (NS) is the most widely used agent in the medical field. However, from its origin to its widespread application, it remains a mystery. Moreover, there is an ongoing debate on whether its existence is reasonable, harmful to the human body, or will still exist in the future. The current review traces back to the origins of NS and provides a brief overview of the current situation of infusion. The purpose may shed some light on the possibility of the existence of NS in the future by elaborating on the origin of NS and the research status of the impact of NS on the human body.

The Prevalence and Indications of Intravenous Rehydration Therapy in Hospital Settings: A Systematic Review

(1) Objective: We performed a systematic review to explore the prevalence of intravenous (IV) rehydration therapy in hospital settings, and we assessed it by patient groups and populations. (2) Methods: A systematic review of major databases and grey literature was undertaken from inception to 28 March 2022. Studies reporting prevalence of IV rehydration therapy in a hospital setting were identified. The data were synthesised in a narrative approach. (3) Results: Overall, 29 papers met the inclusion criteria. The prevalence of IV rehydration therapy in paediatric patients ranged from 4.5% (hospitalised with diarrhoea and dehydration) to 100% (admitted to the emergency department with mild to moderate dehydration caused by viral gastroenteritis), and in adults this ranged from 1.5% (had single substance ingestion of modafinil) to 100% (hospitalised with hypercalcemia). The most common indication for IV rehydration therapy in paediatric patients was dehydration due to fluid loss from the gastrointestinal tract. Other causes included malnutrition, neuromuscular disease, bronchiolitis, and influenza. In adults, indications for IV rehydration therapy were much more diverse: fever, diarrhoea, drug intoxication, hypercalcemia, cancer, and postural tachycardia syndrome; (4) Conclusions: This systematic review showed that IV rehydration therapy in paediatric patients is often used to treat dehydration and diarrhoea, while in adults it has a broader spectrum of use. While IV rehydration therapy is important in correcting fluid problems and electrolyte status, the maintenance fluid prescribing practices vary considerably, and guidelines are scarce.

Evaluation and management of hypernatremia in adults: clinical perspectives

Hypernatremia is an occasionally encountered electrolyte disorder, which may lead to fatal consequences under improper management. Hypernatremia is a disorder of the homeostatic status regarding body water and sodium contents. This imbalance is the basis for the diagnostic approach to hypernatremia. We summarize the eight diagnostic steps of the traditional approach and introduce new biomarkers: exclude pseudohypernatremia, confirm glucose-corrected sodium concentrations, determine the extracellular volume status, measure urine sodium levels, measure urine volume and osmolality, check ongoing urinary electrolyte free water clearance, determine arginine vasopressin/copeptin levels, and assess other electrolyte disorders. Moreover, we suggest six steps to manage hypernatremia by replacing water deficits, ongoing water losses, and insensible water losses: identify underlying causes, distinguish between acute and chronic hypernatremia, determine the amount and rate of water administration, select the type of replacement solution, adjust the treatment schedule, and consider additional therapy for diabetes insipidus. Physicians may apply some of these steps to all patients with hypernatremia, and can also adapt the regimens for specific causes or situations.

Influence of acetate- vs. lactate-containing fluid bolus therapy on acid-base status, electrolytes, and plasma lactate in dogs

Objective

Acetate- and lactate-containing fluids influence the acid-base and electrolyte status. This prospective, randomized, clinical study compared two balanced crystalloid solutions regarding their influence on acid-base status, electrolytes, and lactate values, when given to dogs as a resuscitation bolus of 30 mL/kg.

Material and methods

One hundred client-owned dogs presenting to the emergency service with signs of fluid deficits were randomly assigned to receive an intravenous bolus of 30 mL/kg of either a lactate- (LAC), or an acetate-containing solution (ACET). Before and after the bolus, vital parameters were assessed, and a venous blood gas analysis was performed.

Results

Both solutions performed equally well in decreasing the heart rate (ACET: −10 ± 27 bpm, LAC: −12 ± 30 bpm; p = 0.737). The acetate-containing solution caused a significant decrease in plasma lactate levels (p = 0.016), anion gap (p &lt; 0.001), and potassium (p &lt; 0.001), and a significant increase in chloride (p &lt; 0.001), and ionized calcium (p = 0.014). The lactate-containing solution caused a significant decrease in anion gap (p &lt; 0.001), sodium (p = 0.016), and potassium (p = 0.001), and a significant increase in chloride (p &lt; 0.001). ACET causes a stronger decrease in plasma lactate (p = 0.015), sodium (p = 0.039), potassium (p = 0.006), and an increase in chloride (p &lt; 0.001), and ionized calcium (p = 0.016) compared to LAC.

Conclusion

Both solutions caused mild changes in electrolyte concentrations and had minor influence on acid-base status when used for bolus therapy in dogs with fluid deficits. Further studies are needed to evaluate their influence on acid-base status, lactate, and electrolytes when used in larger volumes and for a longer time span.

Pyruvate as a Potential Beneficial Anion in Resuscitation Fluids

There have been ongoing debates about resuscitation fluids because each of the current fluids has its own disadvantages. The debates essentially reflect an embarrassing clinical status quo that all fluids are not quite ideal in most clinical settings. Therefore, a novel fluid that overcomes the limitations of most fluids is necessary for most patients, particularly diabetic and older patients. Pyruvate is a natural potent antioxidant/nitrosative and anti-inflammatory agent. Exogenous pyruvate as an alkalizer can increase cellular hypoxia and anoxia tolerance with the preservation of classic glycolytic pathways and the reactivation of pyruvate dehydrogenase activity to promote oxidative metabolism and reverse the Warburg effect, robustly preventing and treating hypoxic lactic acidosis, which is one of the fatal complications in critically ill patients. In animal studies and clinical reports, pyruvate has been shown to play a protective role in multi-organ functions, especially the heart, brain, kidney, and intestine, demonstrating a great potential to improve patient survival. Pyruvate-enriched fluids including crystalloids and colloids and oral rehydration solution (ORS) may be ideal due to the unique beneficial properties of pyruvate relative to anions in contemporary existing fluids, such as acetate, bicarbonate, chloride, citrate, lactate, and even malate. Preclinical studies have demonstrated that pyruvate-enriched saline is superior to 0.9% sodium chloride. Moreover, pyruvate-enriched Ringer’s solution is advantageous over lactated Ringer’s solution. Furthermore, pyruvate as a carrier in colloids, such as hydroxyethyl starch 130/0.4, is more beneficial than its commercial counterparts. Similarly, pyruvate-enriched ORS is more favorable than WHO-ORS in organ protection and shock resuscitation. It is critical that pay attention first to improving abnormal saline with pyruvate for ICU patients. Many clinical trials with a high dose of intravenous or oral pyruvate were conducted over the past half century, and results indicated its effectiveness and safety in humans. The long-term instability of pyruvate aqueous solutions and para-pyruvate cytotoxicity is not a barrier to the pharmaceutical manufacturing of pyruvate-enriched fluids for ICU patients. Clinical trials with sodium pyruvate-enriched solutions are urgently warranted.

Stability of benzylpenicillin for continuous intravenous infusions: An isotonic formulation for therapeutic use and a low-dose formulation for clinical trial

INTRODUCTION

The objectives of this study were to develop a stability-indicating high performance liquid chromatography (HPLC) assay for benzylpenicillin (BPC) in pharmaceutical fluids, and to investigate the stability of (i) isotonic citrate-buffered BPC solutions at the clinically relevant concentration of 30 mg/mL, and (ii) low concentration citrate-buffered BPC intravenous infusions (5-30 μg/mL).

METHODS

The stability of isotonic BPC solutions containing 3.4 or 7.2 mg/mL sodium citrate was compared against contemporary hypertonic solutions. The HPLC assay was shown to be stability-indicating following acidic, alkali, oxidative and elevated temperature stress testing.

RESULTS

After 7 d storage at 4 °C and 24 h at 35 °C, the concentrations of isotonic BPC 30 mg/mL solutions containing 3.4 and 7.2 mg/mL sodium citrate were 96% and 95% respectively, compared to day 0. After 3 d at 4 °C and 24 h at room temperature (22 °C), the concentrations of isotonic BPC solutions with 3.4 and 7.2 mg/mL sodium citrate were 99% and 96% respectively, compared to day 0. These data were comparable to the hypertonic solutions and meet pharmacopeial stability requirements. Low concentration BPC infusions showed 0.5% and 2.5% degradation after 24 h storage at 22 °C and 35 °C, respectively.

CONCLUSIONS

The isotonic BPC 30 mg/mL formulation is simple to prepare and may offer clinical benefits in settings where hypertonic solutions are problematic. This study provides assurance that high- and low-dose isotonic BPC infusions are stable at room temperature and our findings may be applicable to in vitro studies of BPC.

Feasibility and Safety of Very-Low Contrast Combined Ringer's Solution in Optical Coherence Tomography Imaging

Background

Optical coherence tomography (OCT) is an important modality used in coronary intervention. However, OCT requires a high amount of contrast media, limiting its extensive application in clinical practice. This study compared OCT images of coronary lesions obtained using contrast media and very-low contrast combined Ringer's solution (VLCCR) in patients with acute coronary syndrome (ACS).

Methods

Thirty ACS patients with a total of 36 native lesions and stenoses from 70 to 90% were included in this study. Two kinds of flushing media (a contrast medium and VLCCR) were used in succession in a random order for OCT image pullback of each lesion. VLCCR method is using low volume contrast (4–5 ml) injected into the guiding catheter previously combination with injector infused Ringer's solution instead of pure contrast medium. The safety of procedure was evaluated by recording the patients ‘symptoms, changes of ECG, blood pressure and heart rate. OCT images were analyzed to determine the image clarity. Lumen area and diameter were also measured and the consistency between the two media was compared.

Results

OCT procedure using either contrast or VLCCR did not show any peri-procedural adverse events. There was no difference in changes of blood pressure and heart rate in both procedures, however, VLCCR procedure showed less procedure-related symptoms and ECG changes. We found that the percentage of clear image frame was equivalent between the contrast and VLCCR media (98.0 vs. 96.9%, P = 0.90). We also observed a high degree of similarity between the different lesion phenotypes of ACS for both media. There was a linear correlation of the phenotypes obtained with these two different methods, and a significant correlation was observed between measurements obtained with contrast and VLCCR without correction for the refractive index of VLCCR (correlation coefficients ranged between 0.829 and 0.948).

Conclusions

OCT imaging using VLCCR for blood clearance is feasible and safe and provides similar imaging quality compared to OCT imaging obtained using radiographic contrast media for ACS patients.

New Triazolyl N^N Bidentate Rh(III), Ir(III), Ru(II) and Os(II) Complexes: Synthesis and Characterization, Probing Possible Relations between Cytotoxicity with Transfer Hydrogenation Efficacy and Interaction with Model Biomolecules

Cisplatin and other metallodrugs have realised great success in clinical chemotherapeutic applications as anticancer drugs. However, severe toxicity to healthy cells and non-selectivity to cancer cells remains a challenge, warranting the further search for alternative agents. Herein, we report the anticancer potential of a series of complexes of the general formula [MCl(p-cym)(k2-N^N-L)]+ X− and [MCl(Cp*)(k2-N^N-L)]+ X−, where M is the metal centre (Ru(II), Os(II), Rh(III) or Ir(III)), L = 1-benzyl-4-pyridinyl-1-H-1,2,3-triazole for L1 and 1-picolyl-4-pyridinyl-1-H-1,2,3-triazole for L2 and X− = Cl−, BF4−, BPh4−. When evaluated for activity against some cancerous and non-cancerous cell lines (namely, HeLa, HEK293, A549 and MT4 cancer cells and the normal healthy kidney cells (BHK21)), most of the compounds displayed poor cytotoxicities against cancer cells except for complexes C2 ([RuCl(p-cym)(k2-N^N-L1)]+ BPh4−, EC50 = 9−16 µM and SI = 14), C7 ([RuCl(p-cym)(k2-N^N-L2)]+ BPh4−, EC50 = 17−53 µM and SI = 4) and C11 ([IrCl(Cp*)(k2-N^N-L2)]+ BF4−, EC50 < 5 µM and SI > 10). Selected complexes C1 ([RuCl(p-cym)(k2-N^N-L1)]+ BF4−), C5 ([IrCl(Cp*)(k2-N^N-L1)]+ BF4−) and C11 showed significant interactions with model biomolecules such as guanosine-5′-monophosphate (5′-GMP), bovine serum albumin (BSA) and amino acids under physiological conditions, possibly through carbenylation and N-coordination with 5′-GMP, N-coordination with L-Histidine and L-proline. While the compounds showed good activities in reducing pyruvate to lactate, there was no direct correlation between catalytic transfer hydrogenation of pyruvate and the observed cytotoxic activities. As observed in this work, the marked influence of single atom replacement in ligand may provide a pivotal approach to improving the cytotoxicity and fine-tuning the selectivity to cancer cells.

Cerebrospinal Fluid and Arterial Acid-Base Equilibrium of Spontaneously Breathing Patients with Aneurismal Subarachnoid Hemorrhage

BACKGROUND

Hyperventilation resulting in hypocapnic alkalosis (HA) is frequently encountered in spontaneously breathing patients with acute cerebrovascular conditions. The underlying mechanisms of this respiratory response have not been fully elucidated. The present study describes, applying the physical-chemical approach, the acid-base characteristics of cerebrospinal fluid (CSF) and arterial plasma of spontaneously breathing patients with aneurismal subarachnoid hemorrhage (SAH) and compares these results with those of control patients. Moreover, it investigates the pathophysiologic mechanisms leading to HA in SAH.

METHODS

Patients with SAH admitted to the neurological intensive care unit and patients (American Society of Anesthesiologists physical status of 1 and 2) undergoing elective surgery under spinal anesthesia were enrolled. CSF and arterial samples were collected simultaneously. Electrolytes, strong ion difference (SID), partial pressure of carbon dioxide (PCO₂), weak noncarbonic acids (A_TOT), and pH were measured in CSF and arterial blood samples.

RESULTS

Twenty spontaneously breathing patients with SAH and 25 controls were enrolled. The CSF of patients with SAH, as compared with controls, was characterized by a lower SID (23.1 ± 2.3 vs. 26.5 ± 1.4 mmol/L, p < 0.001) and PCO₂ (40 ± 4 vs. 46 ± 3 mm Hg, p < 0.001), whereas no differences in A_TOT (1.2 ± 0.5 vs. 1.2 ± 0.2 mmol/L, p = 0.95) and pH (7.34 ± 0.06 vs. 7.35 ± 0.02, p = 0.69) were observed. The reduced CSF SID was mainly caused by a higher lactate concentration (3.3 ± 1.3 vs. 1.4 ± 0.2 mmol/L, p < 0.001). A linear association (r = 0.71, p < 0.001) was found between CSF SID and arterial PCO₂. A higher proportion of patients with SAH were characterized by arterial HA, as compared with controls (40 vs. 4%, p = 0.003). A reduced CSF-to-plasma difference in PCO₂ was observed in nonhyperventilating patients with SAH (0.4 ± 3.8 vs. 7.8 ± 3.7 mm Hg, p < 0.001).

CONCLUSIONS

Patients with SAH have a reduction of CSF SID due to an increased lactate concentration. The resulting localized acidifying effect is compensated by CSF hypocapnia, yielding normal CSF pH values and resulting in a higher incidence of arterial HA.

Influence of acetate containing fluid versus lactate containing fluid on acid-base status, electrolyte level, and blood lactate level in dehydrated dogs

BACKGROUND AND AIM

Acetate or lactate buffered, balanced isotonic rehydration fluids are commonly used for fluid therapy in dogs and may influence acid-base and electrolyte status. This study aimed to assess acid-base status, electrolyte levels, and lactate levels in dehydrated dogs after receiving acetate or lactate-containing intravenous rehydration fluids.

MATERIALS AND METHODS

In this prospective, randomized study, 90 dehydrated dogs were included and randomized to receive acetate [Sterofundin® ISO B. Braun Vet Care (STERO), Germany) or lactate (Ringer-Lactat-Lösung nach Hartmann B. Braun Vet Care (RL), Germany] containing intravenous fluids for rehydration. The exclusion criteria were as follows: Age <6 months, liver failure, congestive heart failure, and extreme electrolyte deviation. Physical examination, venous blood gas, and lactate levels were analyzed before and after rehydration. The two groups were compared using t-test and Chi-square test. The significance level was set at p≤0.05.

RESULTS

Post-rehydration heart rate decreased in the STERO group (p<0.001) but not in the RL group (p=0.090). Lactate levels decreased in both groups STERO (p<0.001) and in group RL (p=0.014). Sodium and chloride levels increased during rehydration in group STERO (p<0.001; p<0.001) and group RL (p=0.002; p<0.001). There was a larger decrease in lactate levels in group STERO compared to group RL (p=0.047).

CONCLUSION

Both solutions led to a mild increase in sodium and chloride levels and decreased lactate levels. The acetate-containing solution had an inferior effect on the decrease in lactate level.

Role of copeptin in the diagnosis of traumatic neuroendocrine dysfunction

Traumatic neuroendocrine dysfunction may present with diabetes insipidus (DI) or with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Both these pathologies involve a disturbance in the antidiuretic hormone (ADH) secretion, causing dysnatremias. Diagnosis of posttraumatic ADH dysfunction is hampered by technical difficulties in ADH assessment, and relies mostly on non-specific serum sodium, serum and urine osmolality and diuresis, often leading to misdiagnosis in the acute care setting. Research now focuses on the diagnostic role of copeptin, a peptide secreted together with ADH in an equimolar fashion, and which can be accurately evaluated. Recent studies identified cut-off values of 2.6 pmol/L for baseline copeptin and of 4.9 and 3.8 pmol/L for hypertonic saline infusion and arginine infusion stimulated copeptin, respectively, for the diagnosis of DI in patients with polyuria-polydipsia syndrome. Although SIADH is more difficult to be explored due to its heterogeneity, a ratio of copeptin to urinary sodium below 30 pmol/mmol identifies euvolemic hyponatremia. Exploring the role of copeptin assessment in patients with traumatic brain injury (TBI) in the acute phase may improve their diagnosis accuracy, management and outcome.

Crystalloid and Colloid Compositions and Their Impact

This manuscript will review crystalloid (hypo-, iso-, and hyper-tonic) and colloid (synthetic and natural) fluids that are available for intravenous administration with a focus on their electrolyte, acid-base, colligative, and rheological effects as they relate to each solution's efficacy and safety. The goal is for the reader to better understand the differences between each fluid and the influence on plasma composition, key organ systems, and their implications when used therapeutically in animals with critical illness.

Fluid management: An update for perioperative practitioners

An interprofessional team approach is required to achieve optimum fluid balance for patients during the perioperative period. Incorrect management of fluid assessment and monitoring is associated with adverse outcomes. The scientific understanding of perioperative fluid balance has improved over recent years leading to changes in clinical practice with regard to volume and choice of intravenous fluid. It is important that perioperative practitioners have an understanding of intravenous fluid, fluid compartmentalisation, fluid mechanics and intravascular fluid control mechanisms. Optimum fluid status not only shortens hospital stay but also reduces the incidence of postoperative nausea and vomiting and complication profiles. This article aims to provide perioperative practitioners with a comprehensive overview of fluid management. It will cover important issues surrounding physiological control of fluid balance, choice of intravenous fluid therapy, methods to monitor intravascular volume and factors which influence delivery.

Saline in Dermatology: A literature review

BACKGROUND

Saline, with its different concentrations, is the most used crystalloid solution in medicine. In dermatology, no large studies investigated the benefits of saline. The aim of this article is to review the different possible uses of saline in dermatology, in order to give final recommendations based on the literature review and our experience.

METHODS

We performed a literature search based on PubMed, EMBASE, WHO Global Health Library, Virtual Health Library, Web of Science, Scopus, Google Scholar, and Research gate. using the keywords: saline, physiological, hypertonic, isotonic, hypotonic, salt solution, sodium chloride, 0.9% NaCl, solvent, drug delivery, injection mixtures, diluent, sclerosant, intravenous, intralesional, injection, topical, soaks, fomentation, inhalation, alopecia, psoriasis, scars, atopic dermatitis, eczema, bromoderma, iododerma, lipodystrophy, in various combinations with the Boolean operators AND, OR and NOT. We also hand-searched textbooks.

RESULTS

Saline was used as a diluent with intralesional injection of steroids to minimize the risk of steroid-induced atrophy, being safe and free from preservatives that may precipitate steroids at site of injection and maximize their side effects. Saline has also been used after surgery, when atrophic scars take place or anticipated, and through injection in leishmaniasis, granuloma annulare, atrophic acne scars before using other expensive and less tolerated treatment options.

CONCLUSIONS

The saline represents a helpful option as a diluent with intralesional injection of steroids in various dermatologic therapeutic indications. Moreover, the use of saline in this setting could help to minimize the risk of steroid-induced atrophy. We encourage the use of saline after surgery, when atrophic scars take place or anticipated. Also, we encourage a trial of saline injection in leishmaniasis, granuloma annulare, atrophic acne scars before using other expensive and less tolerated treatment options.

Understanding the principles and aims of intravenous fluid therapy

A balance between the volume of fluid taken in by the human body, and the volume of fluid excreted, is essential for life. Body fluid balance, which is maintained via various homeostatic mechanisms, can be disrupted by injury or disease. Prompt action is usually required to replenish fluid volumes and restore homeostasis, which is achieved via intravenous (IV) fluid therapy. Nurses will often encounter patients with a disrupted fluid balance, particularly in critical care. They will be involved in assessing patients' fluid status and administering and monitoring therapy. Therefore, nurses have an important role in ensuring the safety and effectiveness of IV fluid therapy. This article provides an overview of the principles and aims of IV fluid therapy. It also explains the physiology of body fluid and mechanisms of fluid balance regulation, outlines the principles of patient assessment and indications for IV fluid therapy, and details its potential risks and complications.

Perioperative fluid therapy and intraoperative blood loss in children

Fluid and blood administration are required during surgery in children. The type, amount and tonicity of the intravenous fluids is an important aspect to be considered during anaesthesia management. The physiological differences between adults and children regarding the body water and blood volume needs to be understood. We performed a PUBMED search for English language articles using keywords including 'children', 'intravenous fluid therapy', 'crystalloids', 'colloids', 'fluid homeostasis', 'Starling equation', 'Donnan effect', 'blood loss', 'estimation of blood loss', 'blood management program'. This review discusses the physiological basis, historical background, risk of hyponatraemia, need of glucose in the intravenous fluids as well as the recent concepts in blood transfusion as related to children.

Perioperative fluid management in children: can we sum it all up now?

PURPOSE OF REVIEW

The composition and type of intravenous fluids during paediatric anaesthesia have been subjects of debates for decades. Errors in perioperative fluid management in children may lead to serious complications and a negative outcome. Therefore, in this review, historical and recent developments and recommendations for perioperative fluid management in children are presented, based on physiology and focused on safety and efficacy.

RECENT FINDINGS

Optimized fasting times and liberal clear fluid intake until 1 h improve patient comfort and metabolic and haemodynamic condition after induction of anaesthesia. Physiologically composed balanced isotonic electrolyte solutions are safer than hypotonic electrolyte solutions or saline 0.9% to protect young children against the risks of hyponatraemia and hyperchloraemic acidosis. For intraoperative maintenance infusion, addition of 1-2% glucose is sufficient to avoid hypoglycaemia, lipolysis or hyperglycaemia. Modified fluid gelatine or hydroxyethyl starch in balanced electrolyte solution can safely be used to quickly normalize blood volume in case of perioperative circulatory instability and blood loss.

SUMMARY

Physiologically composed balanced isotonic electrolyte solutions are beneficial for maintaining homeostasis, shifting the status more towards the normal range in patients with preexisting imbalances and have a wide margin of safety in case of accidental hyperinfusion.

Learning (by) osmosis: an approach to teaching osmolarity and tonicity

Understanding osmolarity and tonicity is one of the more challenging endeavors undertaken by students of the natural sciences. We asked students who completed a course in animal physiology to submit an essay explaining what they found most perplexing about this subject, and what in-class activities proved most useful to them. Students had difficulty distinguishing osmolarity from tonicity and determining tonicity based on the solution's composition. The most useful activities were questions requiring simultaneous consideration of both osmolarity and tonicity. Problems that require calculating osmotic concentration and the volumes of body fluid compartments after administration or loss of various solutions emphasize the significance of osmolarity and tonicity in the context of systemic homeostasis and clinical medicine. We hope that our approach to teaching osmolarity and tonicity will prove useful to physiology lecturers who are looking for new ways of introducing this complicated topic to their health professions students.

Saline as a vehicle control does not alter ventilation in male CD-1 mice

Saline (0.9% NaCl) is used in clinical and research settings as a vehicle for intravenous drug administration. While saline is a standard control in mouse studies, there are reports of hyperchloremic metabolic acidosis in high doses. It remains unknown if metabolic acidosis occurs in mice and/or if compensatory increases in breathing frequency and tidal volume accompany saline administration. It was hypothesized that saline administration alters blood pH and the pattern of breathing in conscious CD-1 male mice exposed to air or hypoxia (10% O2 , balanced N2 ). Unrestrained barometric plethysmography was used to quantify breathing frequency (breaths/min; bpm), tidal volume (VT; mL/breath/10 g body weight (BW)), and minute ventilation (VE; mL/min/10 g BW) in two designs: (1) 11-week-old mice with no saline exposure (n = 11) compared to mice with 7 days of 0.9% saline administration (intraperitoneal, i.p.; 10 mL/kg body mass; n = 6). and (2) 17-week-old mice tested before (PRE) and after 1 day (POST1, n = 6) or 7 days (POST7, n = 5) of saline (i.p.; 10 mL/kg body mass). There were no differences when comparing frequency, VT, or VE between groups for either design with room air or hypoxia exposures. Hypoxia increased frequency, VT, and VE compared to room air. Moreover, conscious blood sampling showed no differences in pH, paCO2 , paO2 , or HCO3- in mice without or with 7 days of saline. These findings reveal no differences in ventilation following 1 and/or 7 days of saline administration in mice. Therefore, the use of 0.9% saline as a control is supported for studies evaluating the control of breathing in mice.