Higher serum chloride concentrations are associated with acute kidney injury in unselected critically ill patients

Intrarenal venous flow patterns - Guiding fluid management in sepsis with AKI: A case report

INTRODUCTION

Sepsis often leads to acute kidney injury (AKI), presenting significant challenges in fluid management. This study explores the potential of analyzing intrarenal venous flow (IRVF) patterns to guide tailored fluid therapy, aiming to improve patient outcomes.

PATIENT CONCERNS

A patient was admitted to the intensive care unit with symptoms of septic shock, including fever, severe hypotension, and altered mental status, secondary to a perforated ascending colon adenocarcinoma.

DIAGNOSIS

The patient was diagnosed with perforated ascending colon adenocarcinoma, septic shock, and AKI. Clinical findings included elevated inflammatory markers and impaired renal function.

INTERVENTIONS

The primary therapeutic interventions included surgical resection of the perforated colon, administration of broad-spectrum antibiotics, and fluid resuscitation. Fluid management was guided by continuous monitoring of IRVF, which facilitated precise adjustments to optimize fluid balance and renal perfusion.

OUTCOMES

By utilizing IRVF patterns to guide fluid therapy, the patient's circulatory status and renal function significantly improved. The individualized fluid management approach contributed to better stabilization of the patient's condition.

LESSONS

This case underscores the potential utility of IRVF patterns in guiding fluid management strategies for patients with sepsis and AKI. The main is the benefit of IRVF-guided fluid therapy in improving patient outcomes. Further research is warranted to validate the efficacy and safety of this approach, with the aim of enhancing clinical outcomes in critically ill patients.

Inverse association between serum chloride levels and the risk of atrial fibrillation in chronic kidney disease patients

Background

Electrolyte abnormalities are common symptoms of chronic kidney disease (CKD), but previous studies have mainly focussed on serum potassium and sodium levels. Chloride is an important biomarker for the prognosis of various diseases. However, the relationship between serum chloride levels and atrial fibrillation (AF) in CKD patients is unclear.

Objective

In this study, we sought to determine the association between serum chloride homeostasis and AF in CKD patients.

Methods

In this retrospective cohort study, we included patients who met the diagnostic criteria for CKD in China between 2000 and 2021. Competing risk regression for AF was performed. The associations of the baseline serum chloride concentration with heart failure (HF) and stroke incidence were also calculated by competing risk regression. The association of baseline serum chloride levels with all-cause death was determined by a Cox regression model.

Results

The study cohort comprised 20 550 participants. During a median follow-up of 350 days (interquartile range, 123-730 days), 211 of the 20 550 CKD patients developed AF. After multivariable adjustment, every decrease in the standard deviation of serum chloride (5.02 mmol/l) was associated with a high risk for AF [sub-hazard ratio (sHR) 0.78, 95% confidence interval (CI) 0.65-0.94, P = .008]. These results were also consistent with those of the stratified and sensitivity analyses. According to the fully adjusted models, the serum chloride concentration was also associated with a high risk for incident HF (sHR 0.85, 95% CI 0.80-0.91, P < .001), a high risk for incident stroke (sHR 0.87, 95% CI 0.81-0.94, P < .001), and a high risk for all-cause death [hazard ratio (HR) 0.82, 95% CI 0.73-0.91, P < .001].

Conclusion

In this CKD population, serum chloride levels were independently and inversely associated with the incidence of AF. Lower serum chloride levels were also associated with an increased risk of incident HF, stroke, and all-cause death.

High versus low chloride load in adult hyperglycemic emergencies with acute kidney injury: a multicenter retrospective cohort study

Hyperglycemic emergencies frequently lead to acute kidney injury (AKI) and require treatment with large amount of intravenous fluids. However, the effects of chloride loading on this population have not yet been investigated. We conducted a multicenter, retrospective, cohort study in 21 acute-care hospitals in Japan. The study included hospitalized adult patients with diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic syndrome (HHS) who had AKI upon arrival. The patients were classified into high and low chloride groups based on the amount of chloride administered within the first 48 h of their arrival. The primary outcome was recovery from AKI; secondary outcome was major adverse kidney events within 30 days (MAKE30), including mortality and prolonged renal failure. A total of 390 patients with AKI, including 268 (69%) with DKA and 122 (31%) with HHS, were included in the study. Using the criteria of Kidney Disease Improving Global Outcomes, the severity of AKI in the patients was Stage 1 (n = 159, 41%), Stage 2 (n = 121, 31%), and Stage 3 (n = 110, 28%). The analysis showed no significant difference between the two groups in recovery from AKI (adjusted hazard ratio, 0.96; 95% CI 0.72-1.28; P = 0.78) and in MAKE30 (adjusted odds ratio, 0.91; 95% CI 0.45-1.76; P = 0.80). Chloride loading with fluid administration had no significant impact on recovery from AKI in patients with hyperglycemic emergencies.Trial Registration This study was registered in the UMIN clinical trial registration system (UMIN000025393, registered December 23, 2016).

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

ABSTRACT

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

Modified del Nido cardioplegia is associated with low incidence of low main strong ion difference and hyperchloremia in pediatric patients after cardiac surgery

PURPOSE

The aims of this study were (1) to determine the associations of cardioplegic solutions with postoperative main strong ion difference (mSID), which is the difference between sodium ion concentration and chloride ion concentration ([Cl-]) and (2) to determine the associations of cardioplegic solutions with markers of organ dysfunction.

METHODS

In this retrospective cohort study, patients aged <5 years who underwent cardiac surgery in a tertiary teaching hospital were included. Patients were classified on the basis of the type of cardioplegic solution: modified del Nido cardioplegia (mDNC) and conventional cardioplegia (CC). The effects of mDNC on postoperative mSID and markers of organ functions were examined using propensity-matched analysis.

RESULTS

A total of 500 cases were included. mDNC solution was used in 163 patients (32.6%). After propensity score matching, patients in the mDNC group (n = 152) had significantly higher minimum mSID [28 (26, 30) mEq/L vs. 27 (25, 29) mEq/L, p = 0.02] and lower maximum [Cl-] [112 (109, 114) mEq/L vs. 113 (111, 117) mEq/L, p < 0.001] than patients in the CC group (n = 304). The incidences of low mSID and hyperchloremia in the mDNC group were significantly lower than those in the CC group (63.8 vs. 75.7%, p = 0.01 and 63.2 vs. 79.3%, p < 0.001, respectively). There was no significant difference in the incidence of postoperative acute kidney injury and B-type natriuretic peptide level between the two groups.

CONCLUSION

The use of modified del Nido cardioplegia may reduce the incidence of abnormal mSID and hyperchloremia compared with the use of a chloride-rich cardioplegic solution.

L-Shaped Association of Serum Chloride Level With All-Cause and Cause-Specific Mortality in American Adults: Population-Based Prospective Cohort Study

BACKGROUND

Chloride is the most abundant anion in the human extracellular fluid and plays a crucial role in maintaining homeostasis. Previous studies have demonstrated that hypochloremia can act as an independent risk factor for adverse outcomes in various clinical settings. However, the association of variances of serum chloride with long-term mortality risk in general populations has been rarely investigated.

OBJECTIVE

This study aims to assess the association of serum chloride with all-cause and cause-specific mortality in the general American adult population.

METHODS

Data were collected from 10 survey cycles (1999-2018) of the National Health and Nutrition Examination Survey. All-cause mortality, cardiovascular disease (CVD) mortality, cancer mortality, and respiratory disease mortality data were obtained by linkage to the National Death Index through December 31, 2019. After adjusting for demographic factors and relevant lifestyle, laboratory items, and comorbid factors, weighted Cox proportional risk models were constructed to estimate hazard ratios and 95% CIs for all-cause and cause-specific mortality.

RESULTS

A total of 51,060 adult participants were included, and during a median follow-up of 111 months, 7582 deaths were documented, 2388 of CVD, 1639 of cancer, and 567 of respiratory disease. The weighted Kaplan-Meier survival analyses showed consistent highest mortality risk in individuals with the lowest quartiles of serum chloride. The multivariate-adjusted hazard ratios from lowest to highest quartiles of serum chloride (≤101.2, 101.3-103.2, 103.2-105.0, and ≥105.1 mmol/L) were 1.00 (95% CI reference), 0.77 (95% CI 0.67-0.89), 0.72 (95% CI 0.63-0.82), and 0.77 (95% CI 0.65-0.90), respectively, for all-cause mortality (P for linear trend<.001); 1.00 (95% CI reference), 0.63 (95% CI 0.51-0.79), 0.56 (95% CI 0.43-0.73), and 0.67 (95% CI 0.50-0.89) for CVD mortality (P for linear trend=.004); 1.00 (95% CI reference), 0.67 (95% CI 0.54-0.84), 0.65 (95% CI 0.50-0.85), and 0.65 (95% CI 0.48-0.87) for cancer mortality (P for linear trend=.004); and 1.00 (95% CI reference), 0.68 (95% CI 0.41-1.13), 0.59 (95% CI 0.40-0.88), and 0.51 (95% CI 0.31-0.84) for respiratory disease mortality (P for linear trend=.004). The restricted cubic spline analyses revealed the nonlinear and L-shaped associations of serum chloride with all-cause and cause-specific mortality (all P for nonlinearity<.05), in which lower serum chloride was prominently associated with higher mortality risk. The associations of serum chloride with mortality risk were robust, and no significant additional interaction effect was detected for all-cause mortality and CVD mortality (P for interaction>.05).

CONCLUSIONS

In American adults, decreased serum chloride concentrations were independently associated with increased all-cause mortality, CVD mortality, cancer mortality, and respiratory disease mortality. Our findings suggested that serum chloride may serve as a promising cost-effective health indicator in the general adult population. Further studies are warranted to explore the potential pathophysiological mechanisms underlying the association between serum chloride and mortality.

INCREASE IN CHLORIDE IS ASSOCIATED WITH MAJOR ADVERSE KIDNEY EVENTS IN CRITICALLY ILL PATIENTS

ABSTRACT

Purpose: This study aimed to identify the association between hyperchloremia at intensive care unit (ICU) admission and/or the increase of blood chloride levels and the incidence of major adverse kidney events within 30 days (MAKE30) in critically ill adults. Methods: We conducted a retrospective study to analyze the data of all adult patients admitted to the ICU of a tertiary academic hospital in China between April 2020 and April 2022. Patients were categorized based on their admission chloride levels (hyperchloremia ≥110 mmol/L and nonhyperchloremia <110 mmol/L) and stratified on the increased chloride levels 48 h after ICU admission (∆Cl ≥5 mmol/L and ∆Cl <5 mmol/L). The primary outcome was the MAKE30 incidence, including in-hospital death, new receipt of renal replacement therapy (RRT), and persistent renal dysfunction (PRD). Association between hyperchloremia at ICU admission and/or the increase of chloride and the incidence of MAKE30 were assessed using logistic regression. Result: A total of 2,024 patients with a median age of 67 years (interquartile range [IQR], 55-76 years) and a median Acute Physiology and Chronic Health Evaluation II score of 22 (IQR, 17-28) were included. Hyperchloremia occurred in 30.9% (n = 625), and ΔCl ≥5 mmol/L occurred in 18.5% (n = 375) of all ICU patients. The overall MAKE30 incidence was 33.6% (n = 680), including a 10.9% of 30-day hospital mortality (n = 220; as well as overall in-hospital mortality, 11.8% [n = 238]), a 20.2% (n = 408) of PRD, and a 18.0% (n = 365) of new RRT. After adjusted for confounders, it was found that ΔCl ≥5 mmol/L (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.096-1.93; P = 0.010), but not hyperchloremia (OR, 0.99; 95% CI, 0.77-1.28; P = 0.947), was associated with increased incidence of MAKE30. Conclusion: An increased chloride level in the first 48 h of ICU admission was an independent risk factor for MAKE30, whereas hyperchloremia at ICU admission was not associated with an increased incidence of MAKE30. Large-scale prospective studies are needed to verify our findings.

Electrolyte derangements in critically ill children receiving balanced versus unbalanced crystalloid fluid resuscitation

BACKGROUND

Adult studies have demonstrated potential harm from resuscitation with 0.9% sodium chloride (0.9%NaCl), resulting in increased utilization of balanced crystalloids like lactated ringers (LR). The sodium and potassium content of LR has resulted in theoretical safety concerns, although limited data exists in pediatrics. We hypothesized that use of LR for resuscitation would not be associated with increased electrolyte derangements compared to 0.9%NaCl.

METHODS

A prospective, observational cohort study of critically ill children who received ≥ 20 ml/kg of fluid resuscitation and were admitted to two pediatric intensive care units from November 2017 to February 2020. Fluid groups included patients who received > 75% of fluids from 0.9%NaCl, > 75% of fluids from LR, and a mixed group. The primary outcome was incidence of electrolyte derangements (sodium, chloride, potassium) and acidosis.

RESULTS

Among 559 patients, 297 (53%) received predominantly 0.9%NaCl, 74 (13%) received predominantly LR, and 188 (34%) received a mixture. Extreme hyperkalemia (potassium ≥ 6 mmol/L) was more common in 0.9%NaCl group (5.8%) compared to LR group (0%), p 0.05. Extreme acidosis (pH > 7.1) was more common in 0.9%NaCl group (11%) compared to LR group (1.6%), p 0.016.

CONCLUSIONS

LR is associated with fewer electrolyte derangements compared to 0.9%NaCl. Prospective interventional trials are needed to validate these findings.

Hyperchloremia and association with acute kidney injury in critically ill children

BACKGROUND

Hyperchloremia has been associated with acute kidney injury (AKI) in critically ill adult patients. Data is limited in pediatric patients. Our study sought to determine if an association exists between hyperchloremia and AKI in pediatric patients admitted to the intensive care unit (PICU).

METHODS

This is a single-center retrospective cohort study of pediatric patients admitted to the PICU for greater than 24 h and who received intravenous fluids. Patients were excluded if they had a diagnosis of kidney disease or required kidney replacement therapy (KRT) within 6 h of admission. Exposures were hyperchloremia (serum chloride ≥ 110 mmol/L) within the first 7 days of PICU admission. The primary outcome was the development of AKI using the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Secondary outcomes included time on mechanical ventilation, new KRT, PICU length of stay, and mortality. Outcomes were analyzed using multivariate logistic regression.

RESULTS

There were 407 patients included in the study, 209 in the hyperchloremic group and 198 in the non-hyperchloremic group. Univariate analysis demonstrated 108 (51.7%) patients in the hyperchloremic group vs. 54 (27.3%) in the non-hyperchloremic group (p =  < .001) with AKI. On multivariate analysis, the odds ratio of AKI with hyperchloremia was 2.24 (95% CI 1.39-3.61) (p = .001). Hyperchloremia was not associated with increased odds of mortality, need for KRT, time on mechanical ventilation, or length of stay.

CONCLUSION

Hyperchloremia was associated with AKI in critically ill pediatric patients. Further pediatric clinical trials are needed to determine the benefit of a chloride restrictive vs. liberal fluid strategy. A higher resolution version of the Graphical abstract is available as Supplementary information.

Mutagenic, Acute, and Subchronic Toxicity Studies of the Hesperetin-7-Glucoside-β-Cyclodextrin Inclusion Complex

Hesperetin glucosides such as hesperidin and hesperetin-7-glucoside are abundantly present in citrus fruits and have various pharmacological properties. However, the potential toxicity of hesperetin glucosides remains unclear. An initial assessment of the safety of hesperetin-7-glucoside-β-cyclodextrin inclusion complex (HPTGCD) as a functional food ingredient was undertaken to assess toxicity and mutagenic potential. A bacterial reverse mutation assay (Ames test) using Salmonella typhimurium (strains TA98, TA1535, TA100, and TA1537) and Escherichia coli (strain WP2 uvrA) with HPTGCD (up to 5000 µg/plate) in the absence and presence of metabolic activation was negative. In a single oral (gavage) toxicity study in male and female rats, HPTGCD at dose up to 2000 mg/kg did not produce mortality nor clinical signs of toxicity or change in body weight. In a subchronic oral (dietary admix) toxicity study in rats receiving 0, 1.5, 3, and 5% HPTGCD for 13 weeks, no adverse effects were noted and the no-observed-adverse-effect level (NOAEL) was 5% in the diet (equivalent to 3267.7 mg/kg/day for males and to 3652.4 mg/kg/day for females). These results provide initial evidence of the safety of HPTGCD.

A burden of fluid, sodium, and chloride due to intravenous fluid therapy in patients with respiratory support: a post-hoc analysis of a multicenter cohort study

Background

Fluid creep, including fluids administered as drug diluents and for the maintenance of catheter patency, is the major source of fluid intake in critically ill patients. Although hypoxemia may lead to fluid restriction, the epidemiology of fluid creep in patients with hypoxemia is unclear. This study aimed to address the burden due to fluid creep among patients with respiratory support according to oxygenation status.

Methods

We conducted a post-hoc analysis of a prospective multicenter cohort study conducted in 23 intensive care units (ICUs) in Japan from January to March 2018. Consecutive adult patients who underwent invasive or noninvasive ventilation upon ICU admission and stayed in the ICU for more than 24 h were included. We excluded the following patients when no fluids were administered within 24 h of ICU admission and no records of the ratio of arterial oxygen partial pressure to fractional inspired oxygen. We investigated fluid therapy until 7 days after ICU admission according to oxygenation status. Fluid creep was defined as the fluids administered as drug diluents and for the maintenance of catheter patency when administered at ≤ 20 mL/h.

Results

Among the 588 included patients, the median fluid creep within 24 h of ICU admission was 661 mL (25.2% of the total intravenous-fluid volume), and the proportion of fluid creep gradually increased throughout the ICU stay. Fluid creep tended to decrease throughout ICU days in patients without hypoxemia and in those with mild hypoxemia (p < 0.001 in both patients), but no significant trend was observed in those with severe hypoxemia (p = 0.159). Similar trends have been observed in the proportions of sodium and chloride caused by fluid creep.

Conclusions

Fluid creep was the major source of fluid intake among patients with respiratory support, and the burden due to fluid creep was prolonged in those with severe hypoxemia. However, these findings may not be conclusive as this was an observational study. Interventional studies are, therefore, warranted to assess the feasibility of fluid creep restriction.

Trial registration UMIN-CTR, the Japanese clinical trial registry (registration number: UMIN 000028019, July 1, 2017).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01073-x.

Balanced Crystalloids versus Normal Saline in Adults with Sepsis: A Comprehensive Systematic Review and Meta-Analysis

The crystalloid fluid of choice in sepsis remains debatable. We aimed to perform a comprehensive meta-analysis to compare the effect of balanced crystalloids (BC) vs. normal saline (NS) in adults with sepsis. A systematic search of PubMed, EMBASE, and Web of Sciences databases through 22 January 2022, was performed for studies that compared BC vs. NS in adults with sepsis. Our outcomes included mortality and acute kidney injury (AKI), need for renal replacement therapy (RRT), and ICU length of stay (LOS). Pooled risk ratio (RR) and mean difference (MD) with the corresponding 95% confidence intervals (CIs) were obtained using a random-effect model. Fifteen studies involving 20,329 patients were included. Overall, BC showed a significant reduction in the overall mortality (RR 0.88, 95% CI 0.81-0.96), 28/30-day mortality (RR 0.87, 95% CI 0.79-0.95), and AKI (RR 0.85, 95% CI 0.77-0.93) but similar 90-day mortality (RR 0.96, 95% CI 0.90-1.03), need for RRT (RR 0.91, 95% CI 0.76-1.08), and ICU LOS (MD -0.25 days, 95% CI -3.44, 2.95), were observed between the two groups. However, subgroup analysis of randomized controlled trials (RCTs) showed no statistically significant differences in overall mortality (RR 0.92, 95% CI 0.82-1.02), AKI (RR 0.71, 95% CI 0.47-1.06), and need for RRT (RR 0.71, 95% CI 0.36-1.41). Our meta-analysis demonstrates that overall BC was associated with reduced mortality and AKI in sepsis compared to NS among patients with sepsis. However, subgroup analysis of RCTs showed no significant differences in both overall mortality and AKI between the groups. There was no significant difference in the need for RRT or ICU LOS between BC and NS. Pending further data, our study supports using BC over NS for fluid resuscitation in adults with sepsis. Further large-scale RCTs are necessary to validate our findings.

Acute and sub-acute oral toxicity of aqueous whole leaf and green rind extracts of Aloe vera in Wistar rats

BACKGROUND

Several local communities in Central, Western, Eastern, and Northern regions of Uganda have been using the whole leaf extracts of Aloe vera (L.) Burm. f. (Asphodelaceae) in the treatment of various ailments. Also, several commercial companies sell A. vera as soft drinks in Uganda. However, there are inadequate reports on the toxicities of such preparations. This paper reports the acute and sub-acute oral toxicity of aqueous extracts of whole leaf and green rind of A. vera in Wistar rats.

METHODS

Acute oral toxicity test was carried out in female Wistar rats at doses of 175, 550, 1750, and 5000 mg/kg, p.o. The animals were observed for signs of toxicity for 14 days. Similarly, a sub-acute oral toxicity test was performed in both sexes of rats at doses of 200, 400, and 800 mg/kg, p.o. daily for 28 days. All the groups of animals were monitored for behavioral, morphological, biochemical, and physiological changes, including mortality and compared with respective controls. Body weights were measured weekly while the animals' relative organ weights, hematological, biochemical, gross, and microscopic pathology were examined on day 29.

RESULTS

There was no mortality or apparent behavioral changes at the doses tested in acute and sub-acute oral toxicity tests. Thus, the Median Lethal Dose (LD₅₀) of green rind and whole leaf aqueous extracts was above 5000 mg/kg. Gross anatomy revealed that the rats' relative spleen weight in green rind extract at 200 mg/kg significantly decreased compared to the control group. The creatinine levels in female rats that received green rind extract and the chloride ion levels in male rats administered whole leaf extract were significantly elevated. Conversely, Mean Corpuscular Hemoglobin Concentration (MCHC) levels significantly decreased at lower doses of the green rind extract compared to the control. Histopathology of the kidney revealed the renal interstitium's inflammation at doses of 200 and 800 mg/kg of the whole leaf extract.

CONCLUSION

The findings demonstrated that A. vera green rind and whole leaf extracts are non-toxic at relatively high doses when used for a short duration. Prolonged use of the aqueous whole leaf extract might be associated with kidney toxicity.

Balanced Crystalloid Versus Normal Saline as Resuscitative Fluid in Diabetic Ketoacidosis

Background:

Large volume resuscitation with normal saline (NS) may be associated with iatrogenic hyperchloremia and renal injury.

Objective:

The purpose of this study was to assess clinical outcomes associated with the use of Lactated Ringer’s (LR) compared to NS as resuscitative fluid in diabetic ketoacidosis (DKA).

Methods:

Single-center, retrospective analysis of patients admitted for DKA. The primary objective of this study was to evaluate the incidence of iatrogenic hyperchloremia associated with fluid resuscitation using balanced crystalloid compared to NS.

Results

Iatrogenic hyperchloremia occurred more frequently in the NS group compared to the LR group (74.4% vs 64.2%; P = 0.05). Mean maximum serum chloride was higher in the NS group (115.7 mmol/L vs 113.7 mmol/L; P = 0.004). Incidence of hypernatremia was higher in the NS group (18.3% vs 9.3%; P = 0.02). There was no significant difference in the incidence of AKI; however, mean change in serum creatinine at 48 hours showed a significantly greater decrease in the LR group (-0.15 mg/dL vs -0.04 mg/dL; P = 0.002). No significant differences were found in intensive care unit (ICU) length of stay or total hospital length of stay.

Conclusion and Relevance

This study found a statistically significant reduction in the incidence of iatrogenic hyperchloremia with the use of LR compared to NS as fluid resuscitation in DKA. Serum creatinine was more improved in the LR group versus NS group at 48 hours. Preferential use of balanced crystalloid for fluid resuscitation in DKA may reduce incidence of hyperchloremia and support renal recovery in this population.

Hyperchloremia is associated with poor renal outcome after coronary artery bypass grafting

Background

Hyperchloremia is associated with the risks of several morbidities and mortality. However, its relationship with acute kidney injury (AKI) and end-stage renal disease (ESRD) in patients undergoing coronary artery bypass grafting (CABG) remains unresolved.

Methods

A total of 2977 patients undergoing CABG between 2003 and 2015 were retrospectively reviewed from two tertiary hospitals. Patients were categorized by serum chloride levels into normochloremia (95–105 mmol/L), mild hyperchloremia (106–110 mmol/L), and severe hyperchloremia (> 110 mmol/L). The odds ratios (ORs) for AKI and hazard ratios (HRs) for ESRD were calculated after adjustment for multiple covariates. The death-adjusted risk of ESRD was additionally evaluated.

Results

Postoperative AKI occurred in 798 patients (26.5%). The hyperchloremia group had a higher risk of AKI than the normochloremia group, wherein the risk was incremental depending on the severity of hyperchloremia, as follows: ORs were 1.26 (1.06–1.51) and 1.95 (1.52–2.51) in the mild and severe hyperchloremia groups, respectively. During a median period of 7 years (maximum 15 years), 70 patients (2.3%) had ESRD. The severe hyperchloremia group was at an elevated risk of ESRD compared with the normochloremia group, with an HR of 2.43 (1.28–4.63). Even after adjusting for the competing risk of death, hyperchloremia was associated with the risk of ESRD.

Conclusions

Preoperative hyperchloremia is associated with poor renal outcomes such as AKI and ESRD after CABG. Accordingly, serum chloride should be monitored in patients undergoing CABG.

Subtyping Hyperchloremia among Hospitalized Patients by Machine Learning Consensus Clustering

Background and Objectives: Despite the association between hyperchloremia and adverse outcomes, mortality risks among patients with hyperchloremia have not consistently been observed among all studies with different patient populations with hyperchloremia. The objective of this study was to characterize hyperchloremic patients at hospital admission into clusters using an unsupervised machine learning approach and to evaluate the mortality risk among these distinct clusters. Materials and Methods: We performed consensus cluster analysis based on demographic information, principal diagnoses, comorbidities, and laboratory data among 11,394 hospitalized adult patients with admission serum chloride of >108 mEq/L. We calculated the standardized mean difference of each variable to identify each cluster's key features. We assessed the association of each hyperchloremia cluster with hospital and one-year mortality. Results: There were three distinct clusters of patients with admission hyperchloremia: 3237 (28%), 4059 (36%), and 4098 (36%) patients in clusters 1 through 3, respectively. Cluster 1 was characterized by higher serum chloride but lower serum sodium, bicarbonate, hemoglobin, and albumin. Cluster 2 was characterized by younger age, lower comorbidity score, lower serum chloride, and higher estimated glomerular filtration (eGFR), hemoglobin, and albumin. Cluster 3 was characterized by older age, higher comorbidity score, higher serum sodium, potassium, and lower eGFR. Compared with cluster 2, odds ratios for hospital mortality were 3.60 (95% CI 2.33-5.56) for cluster 1, and 4.83 (95% CI 3.21-7.28) for cluster 3, whereas hazard ratios for one-year mortality were 4.49 (95% CI 3.53-5.70) for cluster 1 and 6.96 (95% CI 5.56-8.72) for cluster 3. Conclusions: Our cluster analysis identified three clinically distinct phenotypes with differing mortality risks in hospitalized patients with admission hyperchloremia.

Association between the use of balanced fluids and outcomes in critically ill children: a before and after study

Background

Hyperchloremia and chloride load have been associated with worse clinical outcomes in critically ill patients. We sought to evaluate the electrolyte profile and clinical outcomes associated with a unit-wide transition from saline to balanced fluids for resuscitation and maintenance fluids in a pediatric intensive care unit (PICU).

Methods

A before and after analysis of all patients admitted to the PICU in a large, urban, academic hospital between August 2018 and March 2020. The transition from the use of saline to the use of balanced fluids for both resuscitation and maintenance fluid as standard care occurred in June 2019. The primary outcome was day 3 acute kidney injury (AKI). The secondary outcomes included mortality, ventilator-free days (VFDs), need for renal replacement therapy (RRT), hospital length of stay (LOS), and electrolyte abnormalities.

Results

Overall, 2863 patients (47% female) with a day 3 AKI rate of 12.9% (n = 130) and a mortality rate of 2.8% (n = 79) were included. After adjusting for confounders (age, PRISM III, mechanical ventilation, and immunocompromised state, septic shock), there were no significant differences in the odds of day 3 AKI (pre 13%, post 12.5%; adjusted odds ratio [aOR] 0.96, 95%CI 0.65–1.42). There were no differences in the secondary outcomes. The post-intervention period had fewer patients with hyperchloremia (pre 15.5% vs. post 10.4%, p =  < 0.0001) and hyperkalemia (pre 3.2% vs. post 1.4%, p = 0.02) and more patients with hypochloremia (pre 9.5% vs. post 14.4%, p =  < 0.0001) and hypokalemia (pre 38.2% vs. post 47.2%, p =  < 0.0001). In reference to the normochloremic cohort, the hypochloremic cohort had an increase in day 3 AKI, need for RRT, hyperchloremia, and hyperkalemia, and a decrease in hypokalemia; and the hyperchloremic cohort had an increase in VFD and a decrease in hospital LOS.

Conclusions

Following a unit-wide implementation of balanced fluids as standard care, there were no differences in rates of day 3 AKI or other clinical outcomes. However, there were lower rates of hyperkalemia and hyperchloremia and higher rates of hypokalemia and hypochloremia. Further evaluation of the effect of balanced fluids and the clinical significance of electrolyte abnormalities in critically ill children is needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03705-3.

Perioperative Renoprotection: General Mechanisms and Treatment Approaches

In the perioperative setting, acute kidney injury (AKI) is a frequent complication, and AKI itself is associated with adverse outcomes such as higher risk of chronic kidney disease and mortality. Various risk factors are associated with perioperative AKI, and identifying them is crucial to early interventions addressing modifiable risk and increasing monitoring for nonmodifiable risk. Different mechanisms are involved in the development of postoperative AKI, frequently picturing a multifactorial etiology. For these reasons, no single renoprotective strategy will be effective for all surgical patients, and efforts have been attempted to prevent kidney injury in different ways. Some renoprotective strategies and treatments have proven to be useful, some are no longer recommended because they are ineffective or even harmful, and some strategies are still under investigation to identify the best timing, setting, and patients for whom they could be beneficial. With this review, we aim to provide an overview of recent findings from studies examining epidemiology, risk factors, and mechanisms of perioperative AKI, as well as different renoprotective strategies and treatments presented in the literature.

Association of Chloride Ion and Sodium-Chloride Difference With Acute Kidney Injury and Mortality in Critically Ill Patients

Objectives

Derangements of chloride ion concentration ([Cl^-]) have been shown to be associated with acute kidney injury and other adverse outcomes. For a physicochemical approach, however, chloride ion concentration should be considered with sodium ion concentration. This study aimed to examine the association of chloride ion concentration and the main strong ion difference (difference between sodium ion concentration and chloride ion concentration) during the first 24 hours after admission into ICU with the development of acute kidney injury and mortality.

Design

Retrospective analyses using the eICU Collaborative Research Database.

Setting

ICUs in 208 hospitals across the United States between 2014 and 2015.

Patients

Critically ill patients who were admitted into the ICU.

Interventions

None.

Measurements and Main Results

A total of 34,801 patients records were analyzed. A multivariable logistic regression analysis for the development of acute kidney injury within 7 days of ICU admission shows that, compared with main strong iron difference 32-34 mEq/as a reference, there were significantly high odds for the development of acute kidney injury in nearly all groups with main strong iron difference more than 34 mEq/L (main strong iron difference = 34-36 mEq/L, odds ratio = 1.17, p = 0.02; main strong iron difference = 38-40 mEq/L, odds ratio = 1.40, p < 0.001; main strong iron difference = 40-42 mEq/L, odds ratio = 1.46, p = 0.001; main strong iron difference > 42 mEq/L, odds ratio = 1.56, p < 0.001). With chloride ion concentration 104-106 mEq/L as a reference, the odds for acute kidney injury were significantly higher only in chloride ion concentration less than or equal to 94 mEq/L and chloride ion concentration 98-100 mEq/L groups. Analyses conducted using inverse probability weighting showed significantly greater odds for ICU mortality in all groups with main strong iron difference greater than 34mEq/L other than the 36-38mEq/L group, as well as in the less than 26-mEq/L group.

Conclusions

Main strong iron difference measured on ICU presentation to the ICU predicts acute kidney injury within 7 days, with low and, in particular, high values representing increased risk. The association between the chloride levels and acute kidney injury is statistically insignificant in models incorporating main strong iron difference, suggesting main strong iron difference is a better predictive marker than chloride on ICU admission.

Dyschloremia is associated with failure to restore renal function in survivors with acute kidney injury: an observation retrospective study

Dyschloremia is common in critically ill patients. However, little is known about the effects of dyschloremia on renal function in patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). A total of 483 patients who received CRRT for AKI were selected and divided into three groups according to their serum chloride concentrations at the time of CRRT initiation. At 90 days after initiating CRRT, renal outcome, i.e., non-complete renal recovery, or renal failure, was assessed in the three groups. The hypochloremia group (serum chloride concentrations < 96 mEq/L, n = 60), the normochloremia group (serum chloride concentrations, 96–111 mEq/L, n = 345), and the hyperchloremia group (serum chloride concentrations > 111 mEq/L, n = 78) were classified. The simplified acute physiology score III was higher in the hyperchloremia and hypochloremia groups than in the normochloremia group. Multivariate logistic regression analyses showed that hypochloremia (odds ratio, 5.12; 95% confidence interval [CI], 2.56–10.23; P < 0.001) and hyperchloremia (odds ratio, 2.53; 95% CI, 1.25–5.13; P = 0.01) were significantly associated with non-complete renal recovery. Similar trends were observed for renal failure. This study showed that dyschloremia was independently associated with failure in restoring renal function following AKI.

The incidence, risk factors, and outcomes of acute kidney injury in the intensive care unit in Sudan

Background There is a paucity of studies in acute kidney injury in the intensive care unit, particularly in Sudan. Objectives The current study has estimated the incidence; risk factors and outcomes of subjects with acute kidney injury developed during admission to the intensive care unit at Fedail Hospital, Khartoum, Sudan. Methodology This was a cross-sectional study conducted in the intensive care unit during the period from July 2018 to June 2019. The data was collected from the clinical profiles of all adult subjects' who have met the published criteria for acute kidney injury. Analysis of association (Chi square test χ²) and multivariate logistic regression were used to analyze data. Main outcome measure The development of acute kidney injury during the subjects' stay in the intensive care unit, length of hospital stay and death. Results From a total of 187 subjects admitted to the intensive care unit; only (105, 56.2%) have met the inclusion criteria (mean age was 61 ± 3.5 years). The main finding of the study was the high incidence of acute kidney injury 39%. The major significant predictors for the development of acute kidney injury with respective odds ratio (OR) were: sepsis (OR 7.5 [95% CI 3-19.7]; P .001); hypovolemia (OR 5.1 [95% CI 2-15.7]; P .001); chronic cardiovascular diseases (OR 3.4 [95% CI 1.2-9.4]; P .017); age > 60 years (OR 2.7 [95% CI 1.2-6.3]; P .018); diabetes mellitus (OR 2.6 [95% CI 1.2-6]; P .02); hypertension (OR 2.4 [95% CI 1.2-5.4]; P .028); and renal replacement therapy (OR 0.2 [95% CI 0.15-0.3]; P .001). The length of hospital stay within the AKI cohort was (6.7 ± 3.8; [range 2-17]) and the mortality rate was (36, 87.8%). Conclusion The major significant predictors for the development of acute kidney injury in the intensive care unit were: sepsis; hypovolemia; chronic cardiovascular diseases; age > 60 years; diabetes mellitus; hypertension; and renal replacement therapy. Sepsis and hypovolemia were common etiologies for acute kidney injury post-admission to the intensive care unit. Acute kidney injury was associated with increased length of hospital stay and a very high absolute mortality rate.

Peak Serum Chloride and Hyperchloremia in Patients Undergoing Cardiac Surgery Is Not Explained by Chloride-Rich Intravenous Fluid Alone: A Post-Hoc Analysis of the LICRA Trial

OBJECTIVES

With the exception of 0.9% saline, little is known about factors that may contribute to increased serum chloride concentration (S_Cl^-) in patients undergoing cardiac surgery. For the present study, the authors sought to characterize the association between administered chloride load from intravenous fluid and other perioperative variables, with peak perioperative S_Cl^-.

DESIGN

Secondary analysis of data from a previously published controlled clinical trial in which patients were assigned to a chloride-rich or chloride-limited perioperative fluid strategy (NCT02020538).

SETTING

Academic medical center.

PARTICIPANTS

The study comprised 1,056 adult patients with normal preoperative S_Cl^- undergoing cardiac surgery.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS: Peak perioperative S_Cl^- and hyperchloremia, defined as peak S_Cl^- >110 mmol/L, were selected as co-primary endpoints. Regression modeling identified factors independently associated with these endpoints. Mean (standard deviation) peak perioperative S_Cl^- was 114 (5) mmol/L, and hyperchloremia occurred in 824 (78.0%) of the cohort. In addition to administered volume of 0.9% saline, multivariate linear and logistic regression modeling consistently associated preoperative S_Cl^- (regression coefficient 0.5; 95% confidence interval [CI] 0.4-0.6 mmol/L; odds ratio 1.60; 95% CI 1.41-1.82 per 1 mmol/L increase) and cardiopulmonary bypass duration (regression coefficient 0.1; 95% CI 0.1-0.2 mmol/L; odds ratio 1.12; 95% CI 1.06-1.19 per 10 minutes) with both co-primary outcomes. Multivariate modeling only explained approximately 50% of variability in peak S_Cl^-.

CONCLUSIONS

The present study's data identified an association for both 0.9% saline administration and other nonfluid variables with peak perioperative S_Cl^- and hyperchloremia. Stand-alone strategies to limit administration of chloride-rich intravenous fluid may have limited ability to prevent hyperchloremia in this setting.

A Preliminary Investigation into the Association of Chloride Concentration on Morbidity and Mortality in Hospitalized Canine Patients

Purpose

To evaluate whole blood chloride concentration and hospital-acquired AKI in hospitalized canine patients. Secondary outcome measures included the volume-adjusted chloride load, in-hospital mortality and length of ICU stay.

Patients and Methods

This is a prospective, observational study. Sixty dogs admitted to the ICU and receiving IV fluid therapy for >24 hours from February 2018 to July 2019. Corrected chloride and creatinine concentrations were obtained twice daily. Total volume of IV fluid and total chloride load were recorded. Volume-adjusted chloride load (VACL) was calculated by dividing the chloride administered by the volume of fluid administered. Hospital-acquired AKI was defined as an increase in creatinine of ≥26.5 μmol/L (0.3 mg/dL) or 150% from baseline to maximum. Survival to hospital discharge or non-survival and ICU length of stay were also recorded.

Results

Fifteen out of 60 patients developed hospital-acquired AKI. Maximum corrected chloride was significantly different in AKI group (median 122.3 mmol/L) vs non-AKI group (median 118.1 mmol/L; p=0.0002). Six out of 60 patients developed hyperchloremia. Hyperchloremic patients were significantly more likely to develop in-hospital AKI (p=0.03). Patients hospitalized ≥2 days had a significantly higher [Cl⁻]_max compared to those with shorter ICU stay (121.8 ± 5.9 mmol/L vs 117.5 ± 4.3 mmol/L; p=0.002). Eight out of 60 patients were non-survivors. Maximum corrected chloride and creatinine concentrations were not significantly different between survivors and non-survivors. VACL was not significantly different between AKI or mortality groups.

Conclusion

Maximum corrected chloride concentration was significantly higher in dogs with hospital-acquired AKI, even amongst dogs without hyperchloremia. Additionally, maximum corrected chloride concentrations were significantly higher in dogs hospitalized in the ICU longer compared to those hospitalized for fewer than two days. There was no significant difference in VACL in any of the outcome groups. Results from this study suggest alterations in chloride may be observed alongside the development of acute kidney injuries. Future studies in critically ill dogs are warranted.

Hospital-Acquired Serum Chloride Derangements and Associated In-Hospital Mortality

Background: We aimed to describe the incidence of hospital-acquired dyschloremia and its association with in-hospital mortality in general hospitalized patients. Methods: All hospitalized patients from 2009 to 2013 who had normal admission serum chloride and at least two serum chloride measurements in the hospital were studied. The normal range of serum chloride was defined as 100–108 mmol/L. Hospital serum chloride levels were grouped based on the occurrence of hospital-acquired hypochloremia and hyperchloremia. The association of hospital-acquired hypochloremia and hyperchloremia with in-hospital mortality was analyzed using logistic regression. Results: Among the total of 39,298 hospitalized patients, 59% had persistently normal hospital serum chloride levels, 21% had hospital-acquired hypochloremia only, 15% had hospital-acquired hyperchloremia only, and 5% had both hypochloremia and hyperchloremia. Compared with patients with persistently normal hospital serum chloride levels, hospital-acquired hyperchloremia only (odds ratio or OR 2.84; p < 0.001) and both hospital-acquired hypochloremia and hyperchloremia (OR 1.72; p = 0.004) were associated with increased in-hospital mortality, whereas hospital-acquired hypochloremia only was not (OR 0.91; p = 0.54). Conclusions: Approximately 40% of hospitalized patients developed serum chloride derangements. Hospital-acquired hyperchloremia, but not hypochloremia, was associated with increased in-hospital mortality.

Serum Chloride Levels at Hospital Discharge and One-Year Mortality among Hospitalized Patients

This study aimed to assess the one-year mortality risk based on discharge serum chloride among the hospital survivors. We analyzed a cohort of adult hospital survivors at a tertiary referral hospital from 2011 through 2013. We categorized discharge serum chloride; ≤96, 97–99, 100–102, 103–105, 106–108, and ≥109 mmoL/L. We performed Cox proportional hazard analysis to assess the association of discharge serum chloride with one-year mortality after hospital discharge, using discharge serum chloride of 103–105 mmoL/L as the reference group. Of 56,907 eligible patients, 9%, 14%, 26%, 28%, 16%, and 7% of patients had discharge serum chloride of ≤96, 97–99, 100–102, 103–105, 106–108, and ≥109 mmoL/L, respectively. We observed a U-shaped association of discharge serum chloride with one-year mortality, with nadir mortality associated with discharge serum chloride of 103–105 mmoL/L. When adjusting for potential confounders, including discharge serum sodium, discharge serum bicarbonate, and admission serum chloride, one-year mortality was significantly higher in both discharge serum chloride ≤99 hazard ratio (HR): 1.45 and 1.94 for discharge serum chloride of 97–99 and ≤96 mmoL/L, respectively; p < 0.001) and ≥109 mmoL/L (HR: 1.41; p < 0.001), compared with discharge serum chloride of 103–105 mmoL/L. The mortality risk did not differ when discharge serum chloride ranged from 100 to 108 mmoL/L. Of note, there was a significant interaction between admission and discharge serum chloride on one-year mortality. Serum chloride at hospital discharge in the optimal range of 100–108 mmoL/L predicted the favorable survival outcome. Both hypochloremia and hyperchloremia at discharge were associated with increased risk of one-year mortality, independent of admission serum chloride, discharge serum sodium, and serum bicarbonate.

The association between serum chloride levels and chronic kidney disease progression: a cohort study

Background

Limited data suggest serum chloride levels associate with mortality in heart failure, chronic kidney disease (CKD), and pulmonary arterial hypertension. Randomized trials have also shown that administration of crystalloid intravenous fluids with lower chloride concentration may have better renal outcomes. However, chloride has not been studied longitudinally for CKD progression.

Methods

We used a prospective cohort of subjects with stage 3 and 4 CKD recruited from a nephrology clinic at a single medical center. Linear regression, linear regression with generalized estimating equations, and Cox proportional hazards models were created for outcomes of overall change in estimated glomerular filtration rate (eGFR), longitudinal changes in eGFR, and time to > 30% decline in eGFR, respectively. Baseline chloride was modeled continuously and categorically, and models were adjusted for potential confounders.

Results

Median follow-up was 1.7 years. Baseline median age was 72 years and median eGFR was 35.7 mL/min/1.73m². In multivariable analysis, higher serum chloride associated with worsened eGFR decline. Every 1 mEq/L increase in chloride associated with an overall eGFR decline of 0.32 mL/min/1.73m² (p = 0.003), while the difference in eGFR decline in the highest quartile of chloride was 3.4 mL/min/1.73m² compared to the lowest quartile (p = 0.004). No association between serum chloride and time to 30% decline in eGFR was observed in multivariable analysis (hazard ratio 1.05 per 1 mEq/L increase in serum chloride, p = 0.103).

Conclusions

In CKD patients, higher serum chloride associated with a modestly steeper rate of eGFR decline, and may be a useful biomarker to predict CKD progression. Further studies are needed to determine causality.

Hypochloremia is associated with increased risk of all-cause mortality in patients in the coronary care unit: A cohort study

Objective

Serum chloride disorders have been gaining increased attention. We aimed to assess the impact of serum chloride on all-cause mortality in critically ill patients in coronary care units (CCUs).

Methods

We extracted clinical data from the Multiparameter Intelligent Monitoring in Intensive Care III database. We used data for the first CCU admission of each patient; baseline data were extracted within 24 hours after CCU admission. Statistical methods included the Lowess smoothing technique, Cox proportional hazards model, and subgroup analyses.

Results

A total 5616 patients who met the inclusion criteria were included. We observed a U-shaped relationship between admission chloride levels and 30-day all-cause mortality. In multivariate analysis adjusted for age, ethnicity, and sex, both hyper- and hypochloremia were significant predictors of risk of 30-day, 90-day, and 365-day all-cause mortality. After adjusting additional clinical characteristics, hypochloremia remained a significant predictor of risk of 30-day all-cause mortality (hazard ratio, 1.47; 95% confidence interval, 1.19–1.83). For 90-day and 365-day all-cause mortality, similar significant robust associations were found.

Conclusions

We observed a U-shaped relationship between admission chloride levels and 30-day all-cause mortality among patients in the CCU. Hypochloremia was associated with increased risk of all-cause mortality in these patients.

Hyperchloremia and acute kidney injury: a retrospective observational cohort study on a general mixed medical-surgical not ICU-hospitalized population

The aim of this observational retrospective cohort study was to analyze the association between hyperchloremia and serum chloride variation with in-hospital acute kidney injury (AKI) and mortality in a general, no-ICU hospitalized population. We performed a retrospective study on inpatient population admitted to Fondazione Policlinico Universitario A. Gemelli IRCCS between January 2010 and December 2014 with inclusion of adult patients with at least two values available for chloride, sodium and creatinine. Hyperchloremia was defined as serum chloride concentration ≥ 108 mmol/L (moderate hyperchloremia: chloremia between 108-110 mmol/L, severe hyperchloremia: chloremia > 110 mmol/L). According to the time of onset of the electrolyte disturbance, hyperchloremia was then classified as hospital acquired (HA) and community acquired (CA). In patients with HA-hyperchloremia, chloride variation (ΔCl) was calculated. In-hospital AKI was defined according to creatinine kinetics criteria occurring 48 h after hospital admission. Logistic regression analysis was used to evaluate the association between the exposures of interest and in-hospital AKI and mortality. A total of 24,912 hospital admissions met the inclusion criteria. Regression analyses showed that only severe HA-hyperchloremia was associated with increased risk of in-hospital AKI [odds ratio (OR) 2.60, 95% confidence interval (CI) 1.58, 4.30, p value < 0.001] and death (OR 3.89, 95% CI 2.11, 7.18, p value < 0.001). With increasing ΔCl, the OR of in-hospital AKI increased progressively (p value for trend = 0.005). In conclusion, severe hyperchloremia is an independent predictor for in-hospital AKI and mortality; HA-hyperchloremia is more detrimental for patient outcome; higher ΔCl from hospital admission is associated with increased risk of AKI.

Incidence and risk factors of acute kidney injury in critically ill patients from a single centre in Brazil: a retrospective cohort analysis

Studies with a comprehensive analysis of the epidemiology of acute kidney injury (AKI) in intensive care units (ICUs) are still limited in developing countries. The aim of this study is to identify the incidence and risk factors of AKI in critically ill patients from a Brazilian ICU. We performed a retrospective analysis of the records of patients admitted to a single-centre adult ICU in Brazil between 1 January 2011 and 31 December 2016. The KDIGO criteria were used to define AKI. Univariate and multivariate data analyses were carried out. We included 1,500 patients. The incidence of AKI was 40.5%, and the AKI dialysis rate was 13%. The predictors of AKI at ICU admission included hypertension [odds ratio (OR) = 1.44, p 0.017], high serum creatinine concentration [OR = 3.54; p < 0.001], low serum albumin concentration [OR = 1.42, p 0.015], high APACHE II score [OR = 2.10; p < 0.001] and high SAPS 3 [OR = 1.75; p < 0.001]. The incidence of AKI was high, and we identified the predictors of AKI among critically ill Brazilian patients. The results of this study may contribute to the implementation of targeted therapies.

Protocol for a prospective observational study on the association of variables obtained by contrast-enhanced ultrasonography and sepsis-associated acute kidney injury

INTRODUCTION

Sepsis commonly results in acute kidney injury (AKI), whereas about 50% of AKI cases are due to sepsis. Sepsis-associated acute kidney injury (SA-AKI) increases morbidity and mortality especially among critically ill patients. This study aims to monitor renal microcirculation perfusion during sepsis using contrast-enhanced ultrasonography (CEUS), and to explore whether CEUS is useful for predicting the development of SA-AKI.

METHODS AND ANALYSIS

This prospective observational study will enrol patients who were diagnosed with sepsis-3 definition. The total of septic or septic shock patients were stratified into AKI (including stages 1, 2 and 3) and non-AKI groups according to Kidney Disease Improving Global Outcomes criteria on days 0, 1, 2 and 7 after admission to the emergency intensive care unit, meanwhile, the CEUS technique will be performed to monitor renal microcirculation perfusion. A multivariable model including all CEUS variables were expected to create for predicting the development of AKI during sepsis. Ultrasonography results, demographic information, therapeutic interventions, survival outcomes, laboratory and other clinical datas will also be collected for further analysis.

ETHICS AND DISSEMINATION

The study protocol was approved on 2 August 2017 by the Ethics Committee of Sir Run Run Shaw Hospital (Zhejiang University Medical College) (approval number: 2016C91401). The results will be published in a peer-reviewed journal and shared with the worldwide medical community within 2 years after the start of the recruitment.

TRIAL REGISTRATION NUMBER

ISRCTN14728986.

"I don't get no respect": the role of chloride in acute kidney injury

Acute kidney injury (AKI) is a major public health problem that complicates 10-40% of hospital admissions. Importantly, AKI is independently associated with increased risk of progression to chronic kidney disease, end-stage renal disease, cardiovascular events, and increased risk of in-hospital and long-term mortality. The chloride content of intravenous fluid has garnered much attention over the last decade, as well as its association with excess use and adverse outcomes, including AKI. Numerous studies show that changes in serum chloride concentration, independent of serum sodium and bicarbonate, are associated with increased risk of AKI, morbidity, and mortality. This comprehensive review details the complex renal physiology regarding the role of chloride in regulating renal blood flow, glomerular filtration rate, tubuloglomerular feedback, and tubular injury, as well as the findings of clinical research related to the chloride content of intravenous fluids, changes in serum chloride concentration, and AKI. Chloride is underappreciated in both physiology and pathophysiology. Although the exact mechanism is debated, avoidance of excessive chloride administration is a reasonable treatment option for all patients and especially in those at risk for AKI. Therefore, high-risk patients and those with "incipient" AKI should receive balanced solutions rather than normal saline to minimize the risk of AKI.

Increase in chloride from baseline is independently associated with mortality in critically ill children

PURPOSE

To determine if there is an association between mortality and admission chloride levels and/or increases in the chloride level in critically ill children.

METHODS

We performed a retrospective cohort study of all patients admitted to the paediatric intensive care unit (PICU) from January 2014 to December 2015. Patients were excluded for the following reasons: (1) age < 90 days or > 18 years, (2) admission to the cardiac intensive care unit, (3) no laboratory values upon admission to the PICU, (4) history of end-stage renal disease, (5) a disorder of chloride transport, and (6) admission for diabetic ketoacidosis. The patients were stratified on the basis of admission chloride levels (hypochloraemia, < 96 mEq/L; normochloraemia, 96-109 mEq/L; and hyperchloraemia, ≥ 110 mEq/L) and dichotomised on the basis of an increase in chloride in the first day (< 5 mEq/L, ≥ 5 mEq/L). Our primary outcome was in-hospital mortality.

RESULTS

A total of 1935 patients [55% female, median age 6.3 years IQR (1.9-13.4)] were included. The overall mortality was 4% (n = 71) and day 2 AKI occurred in 17% (n = 333. Hypochloraemia, hyperchloraemia, and an increase in serum chloride ≥ 5 mEq/L occurred in 2%, 21%, and 12%, respectively. After adjusting for confounders, increase in chloride ≥ 5 mEq/L was associated with a 2.3 (95% CI 1.03-5.21) greater odds of mortality.

CONCLUSIONS

An increase in serum chloride level in the first day of admission is common and an independent risk factor for mortality in critically ill children. Further studies are warranted to identify how chloride disturbances contribute to mortality risk in critically ill children.

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.

Fluid composition and acute kidney injury

PURPOSE OF REVIEW

To describe recent advances in the understanding of the role of fluid composition in renal outcomes in critically ill patients.

RECENT FINDINGS

The debate on fluid composition is now focused in a pragmatic discussion on fluid electrolyte composition. The resurgence of this debate was propelled by several observational studies that suggested that balanced (i.e., low chloride) solutions were associated with less acute kidney injury in critically ill patients. Nevertheless, a cluster randomized trial failed to show any benefit of balanced solutions. This trial, however, may have failed to detect an effect because of low global illness severity and little fluid infused. If balanced solutions are to be associated with less acute kidney injury, it will probably be in high risk, aggressively resuscitated patients. Additionally, the causal loop involving unbalanced solution infusion, induction of hyperchloremia and acute kidney injury is yet to be closed. Other factors, such as buffer type, speed of infusion and temperature, among others, may also be important.

SUMMARY

Recent evidence suggests that crystalloid fluid composition matters and can influence renal outcomes in critically ill patients. Further studies should assess the impact and cost-efficiency of balanced solutions in the context of high-risk scenarios.

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.

Baseline Chloride Levels are Associated with the Incidence of Contrast-Associated Acute Kidney Injury

Although hypo- and hyperchloremia have been associated with worsening renal outcomes, there has been no study that correlates hypo- and hyperchloremia and the incidence of contrast-associated acute kidney injury (CA-AKI). A total of 13,088 patients with less than 2.0 mg/dL of serum creatinine (Cr) who underwent contrast-enhanced abdominal CT (CECT) were included. Patients were divided into 3 groups based on Cl (the hypo-, normo- and hyperchloremia groups). Patients were also classified by baseline Cr (<1.2; the ‘Normal Cr group’ and 1.2–2.0 mg/dL; the ‘Slightly increased Cr group’). Multivariate logistic regression analysis was used to reveal the association between Cl and CA-AKI. Among patients, 2,525 (19.3%) and 241 (1.8%) patients were classified in the hypo- and hyperchloremia group. The incidence of CA-AKI was significantly lower in the normochloremia group (4.0%) compared to the hypo- (5.4%) and hyperchloremia groups (9.5%). On multivariate logistic regression, hypochloremia was significantly associated with the incidence of CA-AKI compared with normochloremia (1.382, P = 0.002). Moreover, hypochloremia was still significantly associated with the incidence of CA-AKI in ‘Normal Cr group’ compared with normochloremia (1.314, P = 0.015), while hyperchloremia did not show significant association with CA-AKI incidence. In conclusion, hypochloremia might be associated with the incidence of CA-AKI even in patients who have normal-range Cr levels.

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.

Chloride in intensive care units: a key electrolyte

Over the past few years, chloride has joined the league of essential electrolytes for critically ill patients. Dyschloremia can occur secondary to various etiologic factors before and during patient admission in the intensive care unit. Some cases are disease-related; others, treatment-related. Chloride abnormalities were shown in animal models to have adverse effects on arterial blood pressure, renal blood flow, and inflammatory markers, which have led to several clinical investigations. Hyperchloremia was studied in several settings and correlated to different outcomes, including death and acute kidney injury. Baseline hypochloremia, to a much lesser extent, has been studied and associated with similar outcomes. The chloride content of resuscitation fluids was also a subject of clinical research. In this review, we describe the effect of dyschloremia on outcomes in critically ill patients. We review the major studies assessing the chloride content of resuscitation fluids in the critically ill patient.