Meta-analysis of high- versus low-chloride content in perioperative and critical care fluid resuscitation

Sepsis: An Update on Current Practices in Diagnosis and Management

Despite several advancements in care over the last few decades, sepsis continues to carry a high morbidity and mortality burden in the United States. With its varied presentations, cases of sepsis are likely to be encountered by general practitioners in both inpatient and outpatient settings. In the recent years, there has been much debate about the appropriate criteria to diagnose patients with sepsis with a concurrent change in management guidelines. This article reviews definitions, diagnosis and treatment guidelines in current practice in the management of patients with sepsis.

Cross-sectional survey on adult acute kidney injury in Chinese ICU: the study protocol (CARE-AKI)

INTRODUCTION

Acute kidney injury (AKI) is one of the most serious syndromes in intensive care unit (ICU) patients, and is a mysterious problem in clinical practice worldwide. Due to unknown aetiology and mechanism, awareness of AKI diagnosis and treatment in China varies, resulting in underestimated incidence and poor prognosis. To solve this problem, we design this national survey of AKI in adult ICUs. Various indexes are included and analysed to classify the epidemiology of adult AKI in Chinese ICUs, including AKI aetiology, risk factors, mortality, prognosis, therapeutic strategies and cognition of ICU medical staff.

METHODS

A multicentre, cross-sectional survey, which will involve about 35 hospitals and 6147 patients from 23 provinces, 4 municipalities and 5 autonomous regions, is planned. All patients who meet the inclusion criteria are eligible to apply for enrolment in the study, which cover baseline demographics, clinical performance, and follow-up related to diagnosis and treatment.

CONCLUSION

The study is expected to fill the gap between China and developed countries, and to provide a theoretical foundation for developing more scientific and standardised approaches to AKI diagnosis and treatment.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the ethics committee of Harbin Medical University Cancer Hospital (registration number KY2017-21). The findings of this review will be communicated through peer-reviewed publications and scientific presentations.

TRIAL REGISTRATION NUMBER

ChiCTR-EOC-17013133; Pre-results.

Hyperchloremia is independently associated with mortality in critically ill children who ultimately require continuous renal replacement therapy

BACKGROUND

The optimal fluid management in critically ill children is currently under investigation with several studies suggesting that hyperchloremia, chloride load, and the use of chloride-rich fluids contribute to worse outcomes.

METHODS

This is a single-center retrospective cohort study of Pediatric Intensive Care Unit patients from 2008 to 2016 requiring continuous renal replacement therapy (CRRT). Patients were excluded if they had end-stage renal disease, a disorder of chloride transport, or concurrent provision of extracorporeal membrane oxygenation therapy.

RESULTS

Patients (n = 66) were dichotomized into two groups (peak chloride (Cl) ≥ 110 mmol/L vs. peak Cl < 110 mmol/L prior to CRRT initiation). Hyperchloremia was present in 39 (59%) children. Baseline characteristics were similar between groups. Fluid overload at CRRT initiation was more common in patients with hyperchloremia (11.5% IQR 3.8-22.4) compared to those without (5.5% IQR 0.9-13.9) (p = 0.04). Mortality was significantly higher in patients with hyperchloremia (n = 26, 67%) compared to those without (n = 8, 29%) (p = 0.006). Patients with hyperchloremia had 10.9 times greater odds of death compared to those without hyperchloremia, after adjusting for percent fluid overload, PRISM III score, time to initiation of CRRT, height, and weight (95% CI 2.4 to 49.5, p = 0.002).

CONCLUSIONS

Hyperchloremia is common among critically ill children prior to CRRT initiation. In this population, hyperchloremia is independently associated with mortality. Further studies are needed to determine the impact of hyperchloremia on all critically ill children and the impact of chloride load on outcomes.

Balanced Crystalloids versus Saline in Critically Ill Adults

BACKGROUND:

Both balanced crystalloids and saline are used for intravenous fluid administration among critically ill adults. Which results in better clinical outcomes remains unknown.

METHODS:

In a pragmatic, cluster-randomized, multiple-crossover trial in five intensive care units at an academic center, we assigned 15,802 adults to receive saline (0.9% sodium chloride) or balanced crystalloids (lactated Ringer’s solution or Plasma-Lyte A®), according to the randomization of the unit to which they were admitted. The primary outcome was Major Adverse Kidney Events within 30 days (MAKE30), i.e., the composite of death, new renal replacement therapy, or persistent creatinine elevation ≥ 200% of baseline – all censored at the first of hospital discharge or 30 days.

RESULTS:

In the balanced crystalloid group, 1,139 patients (14.3%) experienced MAKE30, compared to 1,211 patients (15.4%) in the saline group (marginal odds ratio, 0.91; 95% confidence interval, 0.84–0.99; conditional odds ratio, 0.90; 95% confidence interval, 0.82–0.99; P=0.04). Thirty-day in-hospital mortality was 10.3% in the balanced crystalloid group and 11.1% in the saline group (P=0.06). The incidence of new renal replacement therapy was 2.5% and 2.9% respectively (P=0.08), and the incidence of persistent creatinine elevation was 6.4% and 6.6% respectively (P=0.60).

CONCLUSIONS:

Among critically ill adults, the use of balanced crystalloids for intravenous fluid administration appeared to reduce the composite outcome of in-hospital mortality, new renal replacement therapy, and persistent renal dysfunction compared with the use of saline. (SMART-MED and SMART-SURG ClinicalTrials.gov numbers, NCT02444988 and NCT02547779.)

Fluid resuscitation for acute kidney injury: an empty promise

PURPOSE OF REVIEW

The past decade has seen more advances in our understanding of fluid therapy than the preceding decades combined. What was once thought to be a relatively benign panacea is increasingly being recognized as a potent pharmacological and physiological intervention that may pose as much harm as benefit.

RECENT FINDINGS

Recent studies have clearly indicated that the amount, type, and timing of fluid administration have profound effects on patient morbidity and outcomes. The practice of aggressive volume resuscitation for 'renal protection' and 'hemodynamic support' may in fact be contributing to end organ dysfunction. The practice of early goal-directed therapy for patients suffering from critical illness or undergoing surgery appears to offer no benefit over conventional therapy and may in fact be harmful. A new conceptual model for fluid resuscitation of critically ill patients has recently been developed and is explored here.

SUMMARY

The practice of giving more fluid early and often is being replaced with new conceptual models of fluid resuscitation that suggest fluid therapy be 'personalized' to individual patient pathophysiology.

Hyperchloraemia in sepsis

Chloride represents—quantitatively—the most prevalent, negatively charged, strong plasma electrolyte. Control of chloride concentration is a probable major mechanism for regulating the body’s acid–base balance and for maintaining homeostasis of the entire internal environment. The difference between the concentrations of chloride and sodium constitutes the major contributor to the strong ion difference (SID); SID is the key pH regulator in the body, according to the physicochemical approach. Hyperchloraemia resulting from either underlying diseases or medical interventions is common in intensive care units. Recent studies have demonstrated the importance of hyperchloraemia in metabolic acidosis and in other pathophysiological disorders present in sepsis. The aim of this narrative review is to present the current knowledge about the effects of hyperchloraemia, in relation to the underlying pathophysiology, in septic patients.

Fluids and Organ Dysfunction: A Narrative Review of the Literature and Discussion of 5 Controversial Topics

Evidence-based clinical decision making is at the forefront of modern cardiothoracic anesthesia practice. Therefore, as a field, cardiac anesthesiologist should strive to ensure that the available evidence is of the highest possible quality. In this narrative review, 5 important topics that the authors believe require additional investigation in cardiothoracic anesthesia and critical care related to fluid therapy and organ dysfunction are outlined briefly. In particular, the authors believe that the areas of pulmonary artery catheter use, restrictive versus liberal transfusion strategies, cardiopulmonary bypass prime composition, colloid use in resuscitation and its effects on acute kidney injury, and management of acute kidney injury after cardiac surgery hold many unanswered questions and opportunities for continued improvement in the specialty of cardiac anesthesia. This article accompanies a presentation at the 46th Association of Cardiac Anesthesiologists Annual Meeting on October 22, 2017.

Crystalloid fluid choice in the critically ill : Current knowledge and critical appraisal

Intravenous infusion of crystalloid solutions is one of the most frequently administered medications worldwide. Available crystalloid infusion solutions have a variety of compositions and have a major impact on body systems; however, administration of crystalloid fluids currently follows a "one fluid for all" approach than a patient-centered fluid prescription. Normal saline is associated with hyperchloremic metabolic acidosis, increased rates of acute kidney injury, increased hemodynamic instability and potentially mortality. Regarding balanced infusates, evidence remains less clear since most studies compared normal saline to buffered infusion solutes.; however, buffered solutes are not homogeneous. The term "buffered solutes" only refers to the concept of acid-buffering in infusion fluids but this does not necessarily imply that the solutes have similar physiological impacts. The currently available data indicate that balanced infusates might have some advantages; however, evidence still is inconclusive. Taking the available evidence together, there is no single fluid that is superior for all patients and settings, because all currently available infusates have distinct differences, advantages and disadvantages; therefore, it seems inevitable to abandon the "one fluid for all" strategy towards a more differentiated and patient-centered approach to fluid therapy in the critically ill.

Balanced Crystalloids versus Saline in Critically Ill Adults

BACKGROUND

Both balanced crystalloids and saline are used for intravenous fluid administration in critically ill adults, but it is not known which results in better clinical outcomes.

METHODS

In a pragmatic, cluster-randomized, multiple-crossover trial conducted in five intensive care units at an academic center, we assigned 15,802 adults to receive saline (0.9% sodium chloride) or balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A) according to the randomization of the unit to which they were admitted. The primary outcome was a major adverse kidney event within 30 days - a composite of death from any cause, new renal-replacement therapy, or persistent renal dysfunction (defined as an elevation of the creatinine level to ≥200% of baseline) - all censored at hospital discharge or 30 days, whichever occurred first.

RESULTS

Among the 7942 patients in the balanced-crystalloids group, 1139 (14.3%) had a major adverse kidney event, as compared with 1211 of 7860 patients (15.4%) in the saline group (marginal odds ratio, 0.91; 95% confidence interval [CI], 0.84 to 0.99; conditional odds ratio, 0.90; 95% CI, 0.82 to 0.99; P=0.04). In-hospital mortality at 30 days was 10.3% in the balanced-crystalloids group and 11.1% in the saline group (P=0.06). The incidence of new renal-replacement therapy was 2.5% and 2.9%, respectively (P=0.08), and the incidence of persistent renal dysfunction was 6.4% and 6.6%, respectively (P=0.60).

CONCLUSIONS

Among critically ill adults, the use of balanced crystalloids for intravenous fluid administration resulted in a lower rate of the composite outcome of death from any cause, new renal-replacement therapy, or persistent renal dysfunction than the use of saline. (Funded by the Vanderbilt Institute for Clinical and Translational Research and others; SMART-MED and SMART-SURG ClinicalTrials.gov numbers, NCT02444988 and NCT02547779 .).

Pyruvate as a novel carrier of hydroxyethyl starch 130/0.4 may protect kidney in rats subjected to severe burns

BACKGROUND

The carrier of hydroxyethyl starch (HES) may play a critical role in kidney injury in fluid resuscitation. This study aimed mainly to compare effects of pyruvate-enriched saline with normal saline (NS) and acetate Ringer's (AR) solution as a carrier in HES130/0.4 on kidney function in rats subjected to severe burns.

METHODS

Using a lethal burn model, 140 rats were randomly allocated in seven groups (n = 20): sham group (group S); no fluid after burn (group N); burn resuscitated with NS (group NS); burn resuscitated with pyruvate saline (group PS); burn resuscitated with AR plus pyruvate-HES (group SP); burn resuscitated with AR plus acetate-HES (group SA), and burn resuscitated with AR plus NS-HES (group SN). A low volume (18.75 mL·kg^-1 during 12 h) of HES130/0.4 was infused with the ratio of 1:1 to crystalloids. Renal surface blood flow, blood creatinine and blood urea nitrogen, early sensitive indicators of kidney function: alpha-1 microglobulin, cystatin-C, and neutrophil gelatinase-associated lipocalin in blood and urine, and kidney tissue water contents were determined. Renal histopathological alterations with Paller scores were also measured at 8 h and 24 h after burn (n = 10), respectively.

RESULTS

The results showed in a comparable manner that group SP was the best in three HES groups and group PS was superior to group NS in renal preservation; group SP appeared significantly beneficial compared with group PS in renal surface blood flow, cystatin-C, neutrophil gelatinase-associated lipocalin, water contents, and Paller scores at 8-h or both time points after burn, respectively (all P < 0.05).

CONCLUSIONS

The carrier of HES130/0.4 played a crucial role in kidney injury in fluid resuscitation of rats subjected to severe burns. Pyruvate-enriched HES130/0.4 was superior and HES130/0.4, per se, might be not renocytotoxic, but renoprotective. Further studies are warranted.

Sodium lactate improves renal microvascular thrombosis compared to sodium bicarbonate and 0.9% NaCl in a porcine model of endotoxic shock: an experimental randomized open label controlled study

Background

Sodium lactate seemed to improve fluid balance and avoid fluid overload. The objective of this study was to determine if these beneficial effects can be at least partly explained by an improvement in disseminated intravascular coagulation (DIC)-associated renal microvascular thrombosis.

Methods

Ancillary work of an interventional randomized open label controlled experimental study. Fifteen female “Large White” pigs (2 months old) were challenged with intravenous infusion of E. coli endotoxin. Three groups of five animals were randomly assigned to receive different fluids: a treatment group received sodium lactate 11.2% (SL group); an isotonic control group received 0.9% NaCl (NC group); a hypertonic control group, with the same amount of osmoles and sodium than SL group, received sodium bicarbonate 8.4% (SB group). Glomerular filtration rate (GFR) markers, coagulation and inflammation parameters were measured over a 5-h period. Immediately after euthanasia, kidneys were withdrawn for histological study. Statistical analysis was performed with nonparametric tests and the Dunn correction for multiple comparisons. A p < 0.05 was considered significant.

Results

The direct immunofluorescence study revealed that the percentage of capillary sections thrombosed in glomerulus were significantly lesser in SL group [5 (0–28) %] compared to NC [64 (43–79) %, p = 0.01] and SB [64 (43–79), p = 0.03] groups. Alterations in platelet count and fibrinogen level occurred earlier and were significantly more pronounced in both control groups compared to SL group (p < 0.05 at 210 and 300 min). The increase in thrombin–antithrombin complexes was significantly higher in NC [754 (367–945) μg/mL; p = 0.03] and SB [463 (249–592) μg/mL; p = 0.03] groups than in SL group [176 (37–265) μg/mL]. At the end of the experiment, creatinine clearance was significantly higher in SL group [55.46 (30.07–67.85) mL/min] compared to NC group [1.52 (0.17–27.67) mL/min, p = 0.03].

Conclusions

In this study, we report that sodium lactate improves DIC-associated renal microvascular thrombosis and preserves GFR. These findings could at least partly explain the better fluid balance observed with sodium lactate infusion.

Normal saline for intravenous fluid therapy in critically ill patients

The efficacy and safety of normal saline (NS) for fluid therapy in critically ill patients remain controversy. In this review, we summarized the evidence of randomized controlled trials (RCTs) which compared NS with other solutions in critically ill patients. The results showed that when compared with 6% hydroxyethyl starch (HES), NS may reduce the onset of acute kidney injury (AKI). However, there is no significant different in mortality and incidence of AKI when compared with 10% HES, albumin and buffered crystalloid solution. Therefore, it is important to prescribe intravenous fluid for patients according to their individual condition.

Hyperchloremia Is Associated With Complicated Course and Mortality in Pediatric Patients With Septic Shock

OBJECTIVE

Hyperchloremia is associated with poor outcome among critically ill adults, but it is unknown if a similar association exists among critically ill children. We determined if hyperchloremia is associated with poor outcomes in children with septic shock.

DESIGN

Retrospective analysis of a pediatric septic shock database.

SETTING

Twenty-nine PICUs in the United States.

PATIENTS

Eight hundred ninety children 10 years and younger with septic shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We considered the minimum, maximum, and mean chloride values during the initial 7 days of septic shock for each study subject as separate hyperchloremia variables. Within each category, we considered hyperchloremia as a dichotomous variable defined as a serum concentration greater than or equal to 110 mmol/L. We used multivariable logistic regression to determine the association between the hyperchloremia variables and outcome, adjusted for illness severity. We considered all cause 28-day mortality and complicated course as the primary outcome variables. Complicated course was defined as mortality by 28 days or persistence of greater than or equal to two organ failures at day 7 of septic shock. Secondarily, we conducted a stratified analysis using a biomarker-based mortality risk stratification tool. There were 226 patients (25%) with a complicated course and 93 mortalities (10%). Seventy patients had a minimum chloride greater than or equal to 110 mmol/L, 179 had a mean chloride greater than or equal to 110 mmol/L, and 514 had a maximum chloride greater than or equal to 110 mmol/L. A minimum chloride greater than or equal to 110 mmol/L was associated with increased odds of complicated course (odds ratio, 1.9; 95% CI, 1.1-3.2; p = 0.023) and mortality (odds ratio, 3.7; 95% CI, 2.0-6.8; p < 0.001). A mean chloride greater than or equal to 110 mmol/L was also associated with increased odds of mortality (odds ratio, 2.1; 95% CI, 1.3-3.5; p = 0.002). The secondary analysis yielded similar results.

CONCLUSION

Hyperchloremia is independently associated with poor outcomes among children with septic shock.

Balanced crystalloids vs 0.9% saline for adult patients undergoing non-renal surgery: A meta-analysis

BACKGROUND

Fluid maintenance and resuscitation is an important strategy during major surgeries. There has been a debate on the choice of crystalloids over the past decades. 0.9% saline (normal saline) is more likely to cause hyperchloremic acidosis when compared to balanced crystalloids with low chloride content. Meta-analyses comparing these two kinds of crystalloids have been performed in renal transplantations. We aim to compare the safety of balanced crystalloids to normal saline among adult patients undergoing non-renal surgery.

METHODS

Relevant articles were searched through PubMed, Embase and the Cochrane Library. Nine randomized controlled trials (including 871 participants) comparing balanced crystalloids to normal saline on adult patients undergoing non-renal surgery were finally included. Possible effects were calculated using meta-analysis.

RESULTS

Patients in the normal saline group had significantly lower postoperative pH (MD: 0.05; 95% CI: 0.04-0.06; p < .001; I² = 82%) and base excess (MD: 2.04; 95% CI: 1.44-2.65; p < .001; I² = 87%). The postoperative serum chloride level was significantly higher in the normal saline group (MD: -4.79; 95% CI: -8.13∼-1.45; p = .005; I² = 95%).

CONCLUSION

Comparing to normal saline, balanced crystalloids are more beneficial in keeping postoperative electrolytes and acid-base balance among adult patients undergoing non-renal surgery. Future researches should pay more attention to meaningful clinical outcomes concerning the safety of balanced crystalloids and normal saline.

Intravenous fluids: effects on renal outcomes

Intravenous fluid therapy is the most commonly prescribed inpatient medication in hospitals around the world. Intravenous fluids are drugs and have an indication, a dose, and expected and unintended effects. The type and amount of fluid given to patients are both important, and can either hasten or slow recovery depending on how they are administered. This narrative review provides a brief summary of the effect of intravenous fluid administration on kidney function and on renal outcome measures of relevance to both patients and clinicians. Several large clinical trials of fluid therapy are currently underway, the results of which are likely to change clinical practice.

Effect of hyperchloremia on acute kidney injury in critically ill septic patients: a retrospective cohort study

Background

Hyperchloremia is common in critically ill septic patients. The impact of hyperchloremia on the incidence of acute kidney injury (AKI) is not well studied. We investigated the association between hyperchloremia and AKI within the first 72 h of intensive care unit (ICU) admission.

Methods

6490 ICU adult patients admitted with severe sepsis or septic shock were screened for eligibility. Exclusion criteria included: AKI on admission, baseline estimated glomerular filtration rate (eGFR) <15 ml/min/1.73 m², chronic renal replacement therapy, absent baseline serum creatinine data, and absent serum chloride data on ICU admission.

Results

A total of 1045 patients were available for analysis following the implementation of eligibility criteria: 303 (29%) had hyperchloremia (Cl₀ ≥ 110 mEq/L) on ICU admission, 561 (54%) were normochloremic (Cl₀ 101–109 mEq/L) and 181 (17%) were hypochloremic (Cl₀ ≤ 100 mEq/L). AKI within the first 72 h of ICU stay was the dependent variable. Chloride on ICU admission (Cl₀) and change in Cl by 72 h (ΔCl = Cl₇₂ – Cl₀) were the independent variables. The odds for AKI were not different in the hyperchloremic group when compared to the normochloremic group [adjusted odds ratio (OR) =0.80, 95% confidence interval [CI] (0.51–1.25); p = 0.33] after adjusting for demographics, comorbidities, baseline kidney function, drug exposure and critical illness indicators including cumulative fluid balance and base deficit. Furthermore, within the subgroup of patients with hyperchloremia on ICU admission, neither Cl₀ nor ΔCl was associated with AKI or with moderate/severe AKI (KDIGO Stage ≥2).

Conclusions

Hyperchloremia occurs commonly among critically ill septic patients admitted to the ICU, but does not appear to be associated with an increased risk for AKI within the first 72 h of admission.

Occurrence and improvement of renal dysfunction and serum potassium abnormality during administration of liposomal amphotericin B in patients with hematological disorders: A retrospective analysis

Liposomal amphotericin B (L-AMB) has the potential to cause two major adverse events, renal dysfunction and serum potassium abnormality; however, appropriate clinical management of these events remains unclear. We retrospectively analyzed data regarding 128 hematology patients who received L-AMB in our institute and examined the association between clinical characteristics and renal dysfunction or serum potassium abnormality. We found that the median weight-normalized dose of L-AMB was 2.69mg/kg and the median administration period was 16days. The overall occurrence rates of renal dysfunction and hypokalemia were 55.7% and 76.6%, respectively. Multivariate analysis revealed that pre-existing renal dysfunction (P=0.017) and concomitant use of nephrotoxic (P<0.0001) or antifungal drugs (P=0.012) were independent risk factors for renal dysfunction. A higher infusion volume did not mitigate the risk of renal dysfunction. Hypokalemia occurred significantly less often in men (P=0.028) and in patients who concomitantly used nephrotoxic drugs (P=0.013). Approximately 40% of the adverse events were improved at 30days after L-AMB termination and there was no significant association between these adverse events improvement and L-AMB dosage or infusion volume. Of note, hyperkalemia was observed in more patients who received allogeneic hematopoietic stem cell transplantation (P=0.0303) and concomitant treatment with nephrotoxic drugs (P=0.0281). These results suggest that imprudent reduction of L-AMB dose or redundant intravenous infusion may have minimal benefit for critical patients with suspected invasive fungal infection.

Choice of Fluids for Resuscitation of the Critically Ill: What Nurses Need to Know

Fluid administration is one of the most universal interventions in the intensive care unit; however, there remains a lack of optimal fluid choice in clinical practice. With increasing evidence suggesting that the choice and dose of fluid may influence patient outcomes, it is important to have an understanding of the differences between the various fluid products and these potential effects in order for nurses to navigate the critically ill patient. This article reviews properties, adverse effects, and monitoring of commonly used colloid and crystalloid fluids, providing information that may aid in fluid selection in the intensive care unit.

Perioperative fluid management in major hepatic resection: an integrative review

BACKGROUND

Fluid intervention and vasoactive pharmacological support during hepatic resection depend on the preference of the attending clinician, institutional resources, and practice culture. Evidence-based recommendations to guide perioperative fluid management are currently limited. Therefore, we provide a contemporary clinical integrative overview of the fundamental principles underpinning fluid intervention and hemodynamic optimization for adult patients undergoing major hepatic resection.

DATA SOURCES

A literature review was performed of MEDLINE, EMBASE and the Cochrane Central Registry of Controlled Trials using the terms "surgery", "anesthesia", "starch", "hydroxyethyl starch derivatives", "albumin", "gelatin", "liver resection", "hepatic resection", "fluids", "fluid therapy", "crystalloid", "colloid", "saline", "plasma-Lyte", "plasmalyte", "hartmann's", "acetate", and "lactate". Search results for MEDLINE and EMBASE were additionally limited to studies on human populations that included adult age groups and publications in English.

RESULTS

A total of 113 articles were included after appropriate inclusion criteria screening. Perioperative fluid management as it relates to various anesthetic and surgical techniques is discussed.

CONCLUSIONS

Clinicians should have a fundamental understanding of the surgical phases of the resection, hemodynamic goals, and anesthesia challenges in attempts to individualize therapy to the patient's underlying pathophysiological condition. Therefore, an ideal approach for perioperative fluid therapy is always individualized. Planning and designing large-scale clinical trials are imperative to define the optimal type and amount of fluid for patients undergoing major hepatic resection. Further clinical trials evaluating different intraoperative goal-directed strategies are also eagerly awaited.

Contemporary Approaches to Perioperative IV Fluid Therapy

BACKGROUND

Intravenous fluid therapy is required for most surgical patients, but inappropriate regimens are commonly prescribed. The aim of this narrative review was to provide evidence-based guidance on appropriate perioperative fluid management.

METHOD

We did a systematic literature search of the literature to identify relevant studies and meta-analyses to develop recommendations.

RESULTS

Of 275 retrieved articles, we identified 25 articles to inform this review. "Normal" saline (0.9% sodium chloride) is not physiological and can result in sodium overload and hyperchloremic acidosis. Starch colloid solutions are not recommended in surgical patients at-risk of sepsis or renal failure. Most surgical patients can have clear fluids and/or administration of carbohydrate-rich drinks up to 2 h before surgery. An intraoperative goal-directed fluid strategy may reduce postoperative complications and reduce hospital length of stay. Regular postoperative assessment of the patient's fluid status and requirements should include looking for physical signs of dehydration or hypovolemia, or fluid overload. Both hypovolemia and salt and water overload lead to adverse events, complications and prolonged hospital stay. Urine output can be an unreliable indicator of hydration status in the postoperative surgical patient. Excess fluid administration has been linked to acute kidney injury, gastrointestinal dysfunction, and cardiac and pulmonary complications.

CONCLUSION

There is good evidence supporting the avoidance of unnecessary fasting and the value of an individualized perioperative IV fluid regimen, with transition to oral fluids as soon as possible, to help patients recover from major surgery.

Perioperative administration of buffered versus non-buffered crystalloid intravenous fluid to improve outcomes following adult surgical procedures

BACKGROUND

Perioperative fluid strategies influence clinical outcomes following major surgery. Many intravenous fluid preparations are based on simple solutions, such as normal saline, that feature an electrolyte composition that differs from that of physiological plasma. Buffered fluids have a theoretical advantage of containing a substrate that acts to maintain the body's acid-base status - typically a bicarbonate or a bicarbonate precursor such as maleate, gluconate, lactate, or acetate. Buffered fluids also provide additional electrolytes, including potassium, magnesium, and calcium, more closely matching the electrolyte balance of plasma. The putative benefits of buffered fluids have been compared with those of non-buffered fluids in the context of clinical studies conducted during the perioperative period. This review was published in 2012, and was updated in 2017.

OBJECTIVES

To review effects of perioperative intravenous administration of buffered versus non-buffered fluids for plasma volume expansion or maintenance, or both, on clinical outcomes in adults undergoing all types of surgery.

SEARCH METHODS

We electronically searched the Clinicaltrials.gov major trials registry, the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 6) in the Cochrane Library, MEDLINE (1966 to June 2016), Embase (1980 to June 2016), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to June 2016). We handsearched conference abstracts and, when possible, contacted leaders in the field. We reran the search in May 2017. We added one potential new study of interest to the list of 'Studies awaiting classification' and will incorporate this trial into formal review findings when we prepare the review update.

SELECTION CRITERIA

Only randomized controlled trials that compared buffered versus non-buffered intravenous fluids for surgical patients were eligible for inclusion. We excluded other forms of comparison such as crystalloids versus colloids and colloids versus different colloids.

DATA COLLECTION AND ANALYSIS

Two review authors screened references for eligibility, extracted data, and assessed risks of bias. We resolved disagreements by discussion and consensus, in collaboration with a third review author. We contacted trial authors to request additional information when appropriate. We presented pooled estimates for dichotomous outcomes as odds ratios (ORs) and for continuous outcomes as mean differences (MDs), with 95% confidence intervals (CIs). We analysed data via Review Manager 5.3 using fixed-effect models, and when heterogeneity was high (I² > 40%), we used random-effects models.

MAIN RESULTS

This review includes, in total, 19 publications of 18 randomized controlled trials with a total of 1096 participants. We incorporated five of those 19 studies (330 participants) after the June 2016 update. Outcome measures in the included studies were thematically similar, covering perioperative electrolyte status, renal function, and acid-base status; however, we found significant clinical and statistical heterogeneity among the included studies. We identified variable protocols for fluid administration and total volumes of fluid administered to patients intraoperatively. Trial authors variably reported outcome data at disparate time points and with heterogeneous patient groups. Consequently, many outcome measures are reported in small group sizes, reducing overall confidence in effect size, despite relatively low inherent bias in the included studies. Several studies reported orphan outcome measures. We did not include in the results of this review one large, ongoing study of saline versus Ringer's solution.We found insufficient evidence on effects of fluid therapies on mortality and postoperative organ dysfunction (defined as renal insufficiency leading to renal replacement therapy); confidence intervals were wide and included both clinically relevant benefit and harm: mortality (Peto OR 1.85, 95% CI 0.37 to 9.33; I² = 0%; 3 trials, 6 deaths, 276 participants; low-quality evidence); renal insufficiency (OR 0.82, 95% CI 0.34 to 1.98; I² = 0%; 4 trials, 22 events, 276 participants; low-quality evidence).We noted several metabolic differences, including a difference in postoperative pH measured at end of surgery of 0.05 units - lower in the non-buffered fluid group (12 studies with a total of 720 participants; 95% CI 0.04 to 0.07; I² = 61%). However, this difference was not maintained on postoperative day one. We rated the quality of evidence for this outcome as moderate. We observed a higher postoperative serum chloride level immediately after operation, with use of non-buffered fluids reported in 10 studies with a total of 530 participants (MD 6.77 mmol/L, 95% CI 3.38 to 10.17), and this difference persisted until day one postoperatively (five studies with a total of 258 participants; MD 8.48 mmol/L, 95% CI 1.08 to 15.88). We rated the quality of evidence for this outcome as moderate.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to show effects of perioperative administration of buffered versus non-buffered crystalloid fluids on mortality and organ system function in adult patients following surgery. Benefits of buffered fluid were measurable in biochemical terms, particularly a significant reduction in postoperative hyperchloraemia and metabolic acidosis. Small effect sizes for biochemical outcomes and lack of correlated clinical follow-up data mean that robust conclusions on major morbidity and mortality associated with buffered versus non-buffered perioperative fluid choices are still lacking. Larger studies are needed to assess these relevant clinical outcomes.

Intravenous fluid and electrolyte administration in elective gastrointestinal surgery: mechanisms of excessive therapy

INTRODUCTION While clinical guidelines stress the importance of the judicious perioperative intravenous fluid administration, data show that adherence to these protocols is poor. The reasons have not been identified. We therefore audited the magnitude and indications of fluid and electrolyte administration in a teaching hospital. We hypothesised that epidural analgesia is associated with excessive fluid therapy. MATERIALS AND METHODS Intravenous fluid and electrolyte administration during the day of surgery and the subsequent 2 days in consecutive patients undergoing elective gastrointestinal surgery between November 2013 and May 2014 were retrospectively audited. Timing, volumes and indications were recorded. RESULTS One hundred patients undergoing elective gastrointestinal resection were studied. Patients received 9030 ml ± 2860 ml (mean ± standard deviation) intravenous fluids containing a total of 1180 ml ± 420 mmol sodium and resulting in a cumulative fluid balance of +5120 ml ± 2510 ml; 44% ± 14% of total volumes were given in theatre. Nearly all fluid was given for maintenance, 100% (96-100%, interquartile range), with 17 patients only receiving replacement or resuscitation. Independent predictors of increased volumes included open surgery, upper gastrointestinal surgery, increased duration and epidural analgesia but not body weight. Postoperative fluid volume was the only independent predictor of postoperative complication grade (P = 0.0044). CONCLUSIONS Despite published guidelines, perioperative fluid and electrolyte administration were excessive and were associated with postoperative morbidity. Substantial volumes were administered in theatre. Nearly all administration was for maintenance, yet patients received approximately five times the amount of sodium required. Epidural analgesia was an independent predictor of fluid volumes but body weight was not.

Balanced versus isotonic saline resuscitation-a systematic review and meta-analysis of randomized controlled trials in operation rooms and intensive care units

BACKGROUND

Fluid resuscitation is the cornerstone in treatment of shock, and intravenous fluid administration is the most frequent intervention in operation rooms and intensive care units (ICUs). The composition of fluids used for fluid resuscitation gained interest over the past decade, with recent focus on whether balanced solutions should be preferred over isotonic saline.

METHODS

Systematic review and meta-analysis of randomized controlled trials (RCTs) comparing fluid resuscitation with a balanced solution versus isotonic saline in adult patients in operation room or ICUs. Primary outcome was in-hospital mortality, secondary outcomes included occurrence of acute kidney injury (AKI) and need for renal replacement therapy (RRT).

RESULTS

The search identified 11 RCTs involving 2,703 patients; 8 trials were conducted in operation room and 3 in ICU. In-hospital mortality, as well as the occurrence of AKI and need for RRT was not different between resuscitation with balanced solutions versus isotonic saline, neither in operation room nor in ICU patients. Serum chloride levels, but not arterial pH, were significantly lower in patients resuscitated with balanced solutions.

CONCLUSIONS

Currently evidence insufficiently supports the use of balanced over isotonic saline for fluid resuscitation to improve outcome of operation room and ICU patients.

Balanced Crystalloids versus Saline in the Intensive Care Unit. The SALT Randomized Trial

RATIONALE

Saline is the intravenous fluid most commonly administered to critically ill adults, but it may be associated with acute kidney injury and death. Whether use of balanced crystalloids rather than saline affects patient outcomes remains unknown.

OBJECTIVES

To pilot a cluster-randomized, multiple-crossover trial using software tools within the electronic health record to compare saline to balanced crystalloids.

METHODS

This was a cluster-randomized, multiple-crossover trial among 974 adults admitted to a tertiary medical intensive care unit from February 3, 2015 to May 31, 2015. The intravenous crystalloid used in the unit alternated monthly between saline (0.9% sodium chloride) and balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A). Enrollment, fluid delivery, and data collection were performed using software tools within the electronic health record. The primary outcome was the difference between study groups in the proportion of isotonic crystalloid administered that was saline. The secondary outcome was major adverse kidney events within 30 days (MAKE30), a composite of death, dialysis, or persistent renal dysfunction.

MEASUREMENTS AND MAIN RESULTS

Patients assigned to saline (n = 454) and balanced crystalloids (n = 520) were similar at baseline and received similar volumes of crystalloid by 30 days (median [interquartile range]: 1,424 ml [500-3,377] vs. 1,617 ml [500-3,628]; P = 0.40). Saline made up a larger proportion of the isotonic crystalloid given in the saline group than in the balanced crystalloid group (91% vs. 21%; P < 0.001). MAKE30 did not differ between groups (24.7% vs. 24.6%; P = 0.98).

CONCLUSIONS

An electronic health record-embedded, cluster-randomized, multiple-crossover trial comparing saline with balanced crystalloids can produce well-balanced study groups and separation in crystalloid receipt. Clinical trial registered with www.clinicaltrials.gov (NCT 02345486).

Balanced crystalloids for septic shock resuscitation

Timely fluid administration is crucial to maintain tissue perfusion in septic shock patients. However, the question concerning which fluid should be used for septic shock resuscitation remains a matter of debate. A growing body of evidence suggests that the type, amount and timing of fluid administration during the course of sepsis may affect patient outcomes. Crystalloids have been recommended as the first-line fluids for septic shock resuscitation. Nevertheless, given the inconclusive nature of the available literature, no definitive recommendations about the most appropriate crystalloid solution can be made. Resuscitation of septic and non-septic critically ill patients with unbalanced crystalloids, mainly 0.9% saline, has been associated with a higher incidence of acid-base balance and electrolyte disorders and might be associated with a higher incidence of acute kidney injury. This can result in greater demand for renal replacement therapy and increased mortality. Balanced crystalloids have been proposed as an alternative to unbalanced solutions in order to mitigate their detrimental effects. Nevertheless, the safety and effectiveness of balanced crystalloids for septic shock resuscitation need to be further addressed in a well-designed, multicenter, pragmatic, randomized controlled trial.

Fluid Resuscitation: Principles of Therapy and "Kidney Safe" Considerations

Fluid resuscitation in the acutely ill must take into consideration numerous elements, including the intravenous solution itself, the phase of resuscitation, and the strategies toward volume management which are paramount. With the advancement in the understanding and implementation of aggressive fluid resuscitation has also come a greater awareness of the resultant fluid toxicity, especially in those that suffer acute kidney injury, and the realization that there is continued ambiguity with regard to volume mitigation and removal in the resuscitated patient. As such, the discussion regarding intravenous solutions continues to evolve especially as it pertains to their effect on kidney and metabolic function, electrolytes, and ultimately patient outcome. In the section below, we review the foundations of fluid resuscitation in the critically ill patient and the different solutions available in this context, including their composition, physiologic properties, and safety and efficacy including the available data regarding "renal-safe" options.

Hypertonic saline in critical illness - A systematic review

INTRODUCTION

The optimal approach to fluid management in critically ill patients is highly debated. Fluid resuscitation using hypertonic saline was used in the past for more than thirty years, but has recently disappeared from clinical practice. Here we provide an overview on the currently available literature on effects of hypertonic saline infusion for fluid resuscitation in the critically ill.

METHODS

Systematic analysis of reports of clinical trials comparing effects of hypertonic saline as resuscitation fluid to other available crystalloid solutions. A literature search of MEDLINE and the Cochrane Controlled Clinical trials register (CENTRAL) was conducted to identify suitable studies.

RESULTS

The applied search strategy produced 2284 potential publications. After eliminating doubles, 855 titles and abstracts were screened and 40 references retrieved for full text analysis. At total of 25 scientific studies meet the prespecified inclusion criteria for this study.

CONCLUSION

Fluid resuscitation using hypertonic saline results in volume expansion and less total infusion volume. This may be of interest in oedematous patients with intravascular volume depletion. When such strategies are employed, renal effects may differ markedly according to prior intravascular volume status. Hypertonic saline induced changes in serum osmolality and electrolytes return to baseline within a limited period in time. Sparse evidence indicates that resuscitation with hypertonic saline results in less perioperative complications, ICU days and mortality in selected patients. In conclusion, the use of hypertonic saline may have beneficial features in selected critically ill patients when carefully chosen. Further clinical studies assessing relevant clinical outcomes are warranted.

Strategies for Intravenous Fluid Resuscitation in Trauma Patients

Intravenous fluid management of trauma patients is fraught with complex decisions that are often complicated by coagulopathy and blood loss. This review discusses the fluid management in trauma patients from the perspective of the developing world. In addition, the article describes an approach to specific circumstances in trauma fluid decision-making and provides recommendations for the resource-limited environment.

Acute kidney injury-an overview of diagnostic methods and clinical management

Acute kidney injury (AKI) is a common condition in multiple clinical settings. Patients with AKI are at an increased risk of death, over both the short and long term, and of accelerated renal impairment. As the condition has become more recognized and definitions more unified, there has been a rapid increase in studies examining AKI across many different clinical settings. This review focuses on the classification, diagnostic methods and clinical management that are available, or promising, for patients with AKI. Furthermore, preventive measures with fluids, acetylcysteine, statins and remote ischemic preconditioning, as well as when dialysis should be initiated in AKI patients are discussed. The classification of AKI includes both changes in serum creatinine concentrations and urine output. Currently, no kidney injury biomarkers are included in the classification of AKI, but proposals have been made to include them as independent diagnostic markers. Treatment of AKI is aimed at addressing the underlying causes of AKI, and at limiting damage and preventing progression. The key principles are: to treat the underlying disease, to optimize fluid balance and optimize hemodynamics, to treat electrolyte disturbances, to discontinue or dose-adjust nephrotoxic drugs and to dose-adjust drugs with renal elimination.

Chloride Content of Fluids Used for Large-Volume Resuscitation Is Associated With Reduced Survival

OBJECTIVE

We sought to investigate if the chloride content of fluids used in resuscitation was associated with short- and long-term outcomes.

DESIGN

We identified patients who received large-volume fluid resuscitation, defined as greater than 60 mL/kg over a 24-hour period. Chloride load was determined for each patient based on the chloride ion concentration of the fluids they received during large-volume fluid resuscitation multiplied by the volume of fluids. We compared the development of hyperchloremic acidosis, acute kidney injury, and survival among those with higher and lower chloride loads.

SETTING

University Medical Center.

PATIENTS

Patients admitted to ICUs from 2000 to 2008.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Among 4,710 patients receiving large-volume fluid resuscitation, hyperchloremic acidosis was documented in 523 (11%). Crude rates of hyperchloremic acidosis, acute kidney injury, and hospital mortality all increased significantly as chloride load increased (p < 0.001). However, chloride load was no longer associated with hyperchloremic acidosis or acute kidney injury after controlling for total fluids, age, and baseline severity. Conversely, each 100 mEq increase in chloride load was associated with a 5.5% increase in the hazard of death even after controlling for total fluid volume, age, and severity (p = 0.0015) over 1 year.

CONCLUSIONS

Chloride load is associated with significant adverse effects on survival out to 1 year even after controlling for total fluid load, age, and baseline severity of illness. However, the relationship between chloride load and development of hyperchloremic acidosis or acute kidney injury is less clear, and further research is needed to elucidate the mechanisms underlying the adverse effects of chloride load on survival.

Patterns of intravenous fluid resuscitation use in adult intensive care patients between 2007 and 2014: An international cross-sectional study

Background

In 2007, the Saline versus Albumin Fluid Evaluation—Translation of Research Into Practice Study (SAFE-TRIPS) reported that 0.9% sodium chloride (saline) and hydroxyethyl starch (HES) were the most commonly used resuscitation fluids in intensive care unit (ICU) patients. Evidence has emerged since 2007 that these fluids are associated with adverse patient-centred outcomes. Based on the published evidence since 2007, we sought to determine the current type of fluid resuscitation used in clinical practice and the predictors of fluid choice and determine whether these have changed between 2007 and 2014.

Methods

In 2014, an international, cross-sectional study was conducted (Fluid-TRIPS) to document current patterns of intravenous resuscitation fluid use and determine factors associated with fluid choice. We examined univariate and multivariate associations between patients and prescriber characteristics, geographical region and fluid type. Additionally, we report secular trends of resuscitation fluid use in a cohort of ICUs that participated in both the 2007 and 2014 studies. Regression analysis were conducted to determine changes in the administration of crystalloid or colloid between 2007 and 2014.

Findings

In 2014, a total of 426 ICUs in 27 countries participated. Over the 24 hour study day, 1456/6707 (21.7%) patients received resuscitation fluid during 2716 resuscitation episodes. Crystalloids were administered to 1227/1456 (84.3%) patients during 2208/2716 (81.3%) episodes and colloids to 394/1456 (27.1%) patients during 581/2716 (21.4%) episodes. In multivariate analyses, practice significantly varied between geographical regions. Additionally, patients with a traumatic brain injury were less likely to receive colloid when compared to patients with no trauma (adjusted OR 0.24; 95% CI 0.1 to 0.62; p = 0.003). Patients in the ICU for one or more days where more likely to receive colloid compared to patients in the ICU on their admission date (adjusted OR 1.75; 95% CI 1.27 to 2.41; p = <0.001).

For secular trends in fluid resuscitation, 84 ICUs in 17 countries contributed data. In 2007, 527/1663 (31.7%) patients received fluid resuscitation during 1167 episodes compared to 491/1763 (27.9%) patients during 960 episodes in 2014. The use of crystalloids increased from 498/1167 (42.7%) in 2007 to 694/960 (72.3%) in 2014 (odds ratio (OR) 3.75, 95% confidence interval (CI) 2.95 to 4.77; p = <0.001), primarily due to a significant increase in the use of buffered salt solutions. The use of colloids decreased from 724/1167 (62.0%) in 2007 to 297/960 (30.9%) in 2014 (OR 0.29, 95% CI 0.19 to 0.43; p = <0.001), primarily due to a decrease in the use of HES, but an overall increase in the use of albumin.

Conclusions

Clinical practices of intravenous fluid resuscitation have changed between 2007 and 2014. Geographical location remains a strong predictor of the type of fluid administered for fluid resuscitation. Overall, there is a preferential use of crystalloids, specifically buffered salt solutions, over colloids. There is now an imperative to conduct a trial determining the safety and efficacy of these fluids on patient-centred outcomes.

Trial registration

Clinicaltrials.gov: Fluid-Translation of research into practice study (Fluid-TRIPS) NCT02002013

Chloride alterations in hospitalized patients: Prevalence and outcome significance

Serum Cl (sCl) alterations in hospitalized patients have not been comprehensively studied in recent years. The aim of this study is to investigate the prevalence and outcome significance of (1) sCl alterations on hospital admission, and (2) sCl evolution within the first 48 hr of hospital admission. We conducted a retrospective study of all hospital admissions in the years 2011–2013 at Mayo Clinic Rochester, a 2000-bed tertiary medical center. Outcome measures included hospital mortality, length of hospital stay and discharge disposition. 76,719 unique admissions (≥18 years old) were studied. Based on hospital mortality, sCl in the range of 105–108 mmol/L was found to be optimal. sCl <100 (n = 13,611) and >108 (n = 11,395) mmol/L independently predicted a higher risk of hospital mortality, longer hospital stay and being discharged to a care facility. 13,089 patients (17.1%) had serum anion gap >12 mmol/L; their hospital mortality, when compared to 63,630 patients (82.9%) with anion gap ≤12 mmol/L, was worse. Notably, patients with elevated anion gap displayed a progressively worsening mortality with rising sCl. sCl elevation within 48 hr of admission was associated with a higher proportion of 0.9% saline administration and was an independent predictor for hospital mortality. Moreover, the magnitude of sCl rise was inversely correlated to the days of patient survival. In conclusion, serum Cl alterations on admission predict poor clinical outcomes. Post-admission sCl increase, due to Cl-rich fluid infusion, independently predicts hospital mortality. These results raise a critical question of whether iatrogenic cause of hyperchloremia should be avoided, a question to be addressed by future prospective studies.

Balanced crystalloids versus saline in the intensive care unit: study protocol for a cluster-randomized, multiple-crossover trial

Background

Saline, the intravenous fluid most commonly administered to critically ill adults, contains a high chloride content, which may be associated with acute kidney injury and death. Whether using balanced crystalloids rather than saline decreases the risk of acute kidney injury and death among critically ill adults remains unknown.

Methods

The Isotonic Solutions and Major Adverse Renal Events Trial (SMART) is a pragmatic, cluster-level allocation, cluster-level crossover trial being conducted between 1 June 2015 and 30 April 2017 in five intensive care units at Vanderbilt University Medical Center in Nashville, TN, USA. SMART compares saline (0.9% sodium chloride) with balanced crystalloids (clinician’s choice of lactated Ringer’s solution or Plasma-Lyte A®). Each intensive care unit is assigned to provide either saline or balanced crystalloids each month, with the assigned crystalloid alternating monthly over the course of the trial. All adults admitted to participating intensive care units during the study period are enrolled and followed until hospital discharge or 30 days after enrollment. The anticipated enrollment is approximately 14,000 patients. The primary outcome is Major Adverse Kidney Events within 30 days—the composite of in-hospital death, receipt of new renal replacement therapy, or persistent renal dysfunction (discharge creatinine ≥200% of baseline creatinine). Secondary clinical outcomes include in-hospital mortality, intensive care unit-free days, ventilator-free days, vasopressor-free days, and renal replacement therapy-free days. Secondary renal outcomes include new renal replacement therapy receipt, persistent renal dysfunction, and incidence of stage 2 or higher acute kidney injury.

Discussion

This ongoing pragmatic trial will provide the largest and most comprehensive comparison to date of clinical outcomes with saline versus balanced crystalloids among critically ill adults.

Trial registration

For logistical reasons, SMART was prospectively registered separately for the medical ICU (SMART-MED; ClinicalTrials.gov identifier: NCT02444988; registered on 11 May 2015; date of first patient enrollment: 1 June 2015) and the nonmedical ICUs (SMART-SURG; ClinicalTrials.gov identifier: NCT02547779; registered on 9 September 2015; date of first patient enrollment: 1 October 2015).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1871-1) contains supplementary material, which is available to authorized users.

Acetate-buffered crystalloid infusate versus infusion of 0.9% saline and hemodynamic stability in patients undergoing renal transplantation : Prospective, randomized, controlled trial

Background

Infusion therapy is one of the most frequently prescribed medications in hospitalized patients. Currently used crystalloid solutes have a variable composition and may therefore influence acid-base status, intracellular and extracellular water content and plasma electrolyte compositions and have a major impact on organ function and outcome. The aim of our study was to investigate whether use of acetate-based balanced crystalloids leads to better hemodynamic stability compared to 0.9% saline.

Methods

We performed a sub-analysis of a prospective, randomized, controlled trial comparing effects of 0.9% saline or an acetate-buffered, balanced crystalloid during the perioperative period in patients with end-stage renal disease undergoing cadaveric renal transplantation. Need for catecholamine therapy and blood pressure were the primary measures.

Results

A total of 150 patients were included in the study of which 76 were randomized to 0.9% saline while 74 received an acetate-buffered balanced crystalloid. Noradrenaline for cardiocirculatory support during surgery was significantly more often administered in the normal saline group, given earlier and with a higher cumulative dose compared to patients receiving an acetate-buffered balanced crystalloid (30% versus 15%, p = 0.027; 68 ± 45 µg/kg versus 75 ± 60 µg/kg, p = 0.0055 and 0.000492 µg/kg body weight/min, ±0.002311 versus 0.000107 µg/kg/min, ±0.00039, p = 0.04, respectively). Mean minimum arterial blood pressure was significantly lower in patients randomized to 0.9% saline than in patients receiving the balanced infusion solution (57.2 [SD 8.7] versus 60.3 [SD 10.2] mm Hg, p = 0.024).

Conclusion

The use of an acetate-buffered, balanced infusion solution results in reduced need for use of catecholamines and cumulative catecholamine dose for hemodynamic support and in less occurrence of arterial hypotension in the perioperative period. Further research in the field is strongly encouraged.