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

Urinary chloride excretion in critical illness and acute kidney injury: a paediatric hypothesis-generating cohort study post cardiopulmonary bypass surgery

Renal chloride metabolism is currently poorly understood but may serve as both a diagnostic and a treatment approach for acute kidney injury. We investigated whether plasma chloride, ammonia and glutamine as well as urinary chloride, ammonium and glutamine concentrations may serve as markers for acute kidney injury in paediatric patients. We conducted a prospective observational trial in a tertiary care paediatric intensive care unit. Ninety-one patients after cardiopulmonary bypass surgery were enrolled. Plasma glutamine, creatinine, (serum) albumin, urinary electrolytes and glutamine were collected pre-cardiopulmonary bypass surgery, at paediatric intensive care unit admission, and at 6, 12, 24, 48 and 72 h after paediatric intensive care unit admission. The urinary strong ion difference was calculated. The median urinary chloride excretion decreased from 51 mmol/L pre-cardiopulmonary bypass to 25 mmol/L at paediatric intensive care unit admission, and increased from 24 h onwards. Patients with acute kidney injury had lower urinary chloride excretion than those without. The median urinary strong ion difference was 59 mmol/L pre-cardiopulmonary bypass, rose to 131 mmol/L at 24 h and fell to 20 mmol/L at 72 h. The plasma chloride rose from 105 mmol/L pre-cardiopulmonary bypass to a maximum of 109 mmol/L at 24 h. At 24 h the plasma chloride concentration was associated with the presence of acute kidney injury. There was no association between plasma or urinary amino acids and chloride excretion or kidney injury. In conclusion, renal chloride excretion decreased in all patients, although this decrease was more pronounced in patients with acute kidney injury. Our findings may reflect a response of the kidneys to critical illness, and acute kidney injury may make these changes more pronounced. Targeting chloride metabolism may offer treatment approaches to acute kidney injury.

A balancing act: drifting away from the reflexive use of "ab"normal saline

Maintenance intravenous fluids are the most frequently ordered medications for hospitalized children. Since the American Association of Pediatrics published national guidelines, there has been an increased reflexive use of isotonic solutions, especially 0.9% saline, as a prophylaxis against hyponatremia. In this educational review, we discuss the potential deleterious effects of using 0.9% saline, including the development of hyperchloremia, metabolic acidosis, acute kidney injury, hyperkalemia, and a proinflammatory state. Balanced solutions with anion buffers cause relatively minimal harm when used in most children. While the literature supporting one fluid choice over the other is variable, we highlight the benefits of balanced solutions over saline and the importance of prescribing fluid therapy that is individualized for each patient.

Update on perioperative fluids

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

Fluid assessment, fluid balance, and fluid overload in sick children: a report from the Pediatric Acute Disease Quality Initiative (ADQI) conference

BACKGROUND

The impact of disorders of fluid balance, including the pathologic state of fluid overload in sick children has become increasingly apparent. With this understanding, there has been a shift from application of absolute thresholds of fluid accumulation to an appreciation of the intricacies of fluid balance, including the impact of timing, trajectory, and disease pathophysiology.

METHODS

The 26th Acute Disease Quality Initiative was the first to be exclusively dedicated to pediatric and neonatal acute kidney injury (pADQI). As part of the consensus panel, a multidisciplinary working group dedicated to fluid balance, fluid accumulation, and fluid overload was created. Through a search, review, and appraisal of the literature, summative consensus statements, along with identification of knowledge gaps and recommendations for clinical practice and research were developed.

CONCLUSIONS

The 26th pADQI conference proposed harmonized terminology for fluid balance and for describing a pathologic state of fluid overload for clinical practice and research. Recommendations include that the terms daily fluid balance, cumulative fluid balance, and percent cumulative fluid balance be utilized to describe the fluid status of sick children. The term fluid overload is to be preserved for describing a pathologic state of positive fluid balance associated with adverse events. Several recommendations for research were proposed including focused validation of the definition of fluid balance, fluid overload, and proposed methodologic approaches and endpoints for clinical trials.

Urinary Chloride Excretion Postcardiopulmonary Bypass in Pediatric Patients-A Pilot Study

The aim of this study was to describe renal chloride metabolism following cardiopulmonary bypass (CPB) surgery in pediatric patients. A prospective observational trial in a tertiary pediatric intensive care unit (PICU) with 20 recruited patients younger than 2 years following CPB surgery was conducted. Urinary electrolytes, plasma urea, electrolytes, creatinine, and arterial blood gases were collected preoperatively, on admission to PICU and at standardized intervals thereafter. The urinary and plasma strong ion differences (SID) were calculated from these results at each time point. Fluid input and output and electrolyte and drug administration were also recorded. Median chloride administration was 67.7 mmol/kg over the first 24 hours. Urinary chloride (mmol/L; median interquartile range [IQR]) was 30 (19, 52) prior to surgery, 15 (15, 65) on admission, and remained below baseline until 24 hours. Plasma chloride (mmol/L; median [IQR]) was 105 (98, 107) prior to surgery and 101 (101, 106) on admission to PICU. It then increased from baseline, but remained within normal limits, for the remainder of the study. The urinary SID increased from 49.8 (19.1, 87.2) preoperatively to a maximum of 122.7 (92.5, 151.8) at 6 hours, and remained elevated until 48 hours. Plasma and urinary chloride concentrations were not associated with the development of acute kidney injury. Urinary chloride excretion is impaired after CPB. The urinary SID increase associated with the decrease in chloride excretion suggests impaired production and/or excretion of ammonium by the nephron following CPB, with gradual recovery postoperatively.

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.

Fluid bolus therapy in pediatric sepsis: a narrative review

Leading cause of death in children under five, pediatric sepsis remains a significant global health threat. The 2020 Surviving Sepsis Campaign guidelines revised the management of septic shock and sepsis-associated organ dysfunction in children. In addition to empiric broad-spectrum antibiotics, fluid bolus therapy is one of the cornerstones of management, due to theoretical improvement of cardiac output, oxygen delivery and organ perfusion. Despite a very low level of evidence, the possible benefit of balanced crystalloids in sepsis resuscitation has led to discussion on their position as the ideal fluid. However, the latest adult data are not consistent with this, and the debate is still ongoing in pediatrics. We provide here the current state of knowledge on fluid bolus therapy in pediatric sepsis with emphasis on balanced crystalloids.

Association of early dysnatremia with mortality in the neonatal intensive care unit: results from the AWAKEN study

OBJECTIVE

To determine the association of dysnatremia in the first postnatal week and risk of acute kidney injury (AKI) and mortality.

STUDY DESIGN

A secondary analysis of 1979 neonates in the AWAKEN cohort evaluated the association of dysnatremia with (1) AKI in the first postnatal week and (2) mortality, utilizing time-varying Cox proportional hazard models.

RESULT

Dysnatremia developed in 50.2% of the cohort and was not associated with AKI. Mortality was associated with hyponatremia (HR 2.15, 95% CI 1.07-4.31), hypernatremia (HR 4.23, 95% CI 2.07-8.65), and combined hypo/hypernatremia (HR 6.39, 95% CI 2.01-14.01). In stratified models by AKI-status, hypernatremia and hypo/hypernatremia increased risk of mortality in neonates without AKI.

CONCLUSION

Dysnatremia within the first postnatal week was associated with increased risk of mortality. Hypernatremia and combined hypo/hypernatremia remained significantly associated with mortality in neonates without AKI. This may reflect fluid strategies kidney injury independent of creatinine and urine-output defined AKI, and/or systemic inflammation.

Controversies in paediatric acute kidney injury and continuous renal replacement therapy: can paediatric care lead the way to precision acute kidney injury medicine?

PURPOSE OF REVIEW

Paediatric patients represent a unique challenge for providers managing acute kidney injury (AKI). Critical care for these children requires a precise approach to assessment, diagnostics and management.

RECENT FINDINGS

Primarily based on observational data, large epidemiologic datasets have demonstrated a strong association between AKI prevalence (one in four critically ill children) and poor patient outcome. Drivers of AKI itself are multifactorial and the causal links between AKI and host injury remain incompletely defined, creating a management paradigm primarily supportive in nature. The previous decades of research have focused primarily on elucidating the population-level epidemiologic signal of AKI and use of renal replacement therapy (RRT), but in order to reverse the course of the AKI 'epidemic', future decades will require more attention to the individual patient. A patient-level approach to AKI in children will require sophisticated approaches to risk stratification, diagnostics and targeted utilization of therapies (both supportive and targeted towards drivers of injury).

SUMMARY

In this review, we will summarize the past, present and future of AKI care in children, discussing the ongoing work and future goals of a personalized approach to AKI medicine.

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.

Hyperchloremia on Admission to Pediatric Intensive Care in Mechanically Ventilated Children is Associated with Impaired Renal Function

Objective  There is recent interest in the association between hyperchloremic metabolic acidosis and adverse outcomes. In vitro, hyperchloremia causes renal vasoconstriction and fall in glomerular filtration rate (GFR). The objective of this retrospective, observational study is to examine associations between chloride level at admission to pediatric intensive care (PICU) and worst GFR and requirement for renal replacement therapy. Materials and Methods  All admissions to PICU between 2009 and 2019 who received invasive mechanical ventilation and had blood gas analysis performed were included. Data analyzed included patient characteristics (age, gender, diagnosis, pediatric index of mortality [PIM]-2 score); results of initial blood gas; and maximum serum creatinine (then used to calculate minimum GFR). Primary outcome measure was worst GFR during PICU stay. Secondary outcome measures were requirement for renal replacement therapy and PICU mortality. Multivariable regression analysis was used to assess if admission chloride level was independently predictive of minimum GFR during PICU stay and to examine associations between hyperchloremia (>110 mEq/L) at admission and requirement for renal replacement therapy after adjustment for confounders. Results  Data were available for 2,217 patients. Median age was 16.4 months and 39% of patients were hyperchloremic at admission to PICU. Admission chloride level was independently predictive of worst GFR during PICU stay after adjustment for known confounders. Patients with hyperchloremia were not more likely to require renal replacement therapy or die than patients with normochloremia. Conclusion  Prospective studies are necessary to determine if high chloride, specifically chloride containing resuscitation fluids, have a causal relationship with poor outcomes.

Maintenance fluid management in pediatrics: Current practice and quality improvement achievements

The long-standing use of hypotonic fluids in pediatric maintenance fluids has been challenged in recent years due to concerns over iatrogenic hyponatremia causing morbidity and mortality. Newer research has highlighted the safety of isotonic fluid alternatives. The American Academy of Pediatrics published an evidenced-based Clinical Practice Guideline in December of 2018 (Feld et al., 2018) to support the routine use of isotonic solutions in pediatric maintenance fluids. This article will also highlight relevant history, current practice, and a quality improvement project to standardize isotonic fluid use in the inpatient pediatric setting.

Pediatric Mortality and Acute Kidney Injury Are Associated with Chloride Abnormalities in Intensive Care Units in the United States: A Multicenter Observational Study

Our objective was to determine in children in the intensive care unit (ICU) the incidence of hyperchloremia (>110 mmol/L) and hypochloremia (<98 mmol/L), the association of diagnoses with chloride abnormalities, and the associations of mortality and acute kidney injury (AKI) with chloride abnormalities. We analyzed the initial, maximum, and minimum chloride measurements of 14,684 children in the ICU with ≥1 chloride measurement in the Health Facts database between 2009 and 2016. For hyperchloremia and hypochloremia compared with normochloremia, mortality rates increased three to fivefold and AKI rates increased 1.5 to threefold. The highest mortality rate (7.7%; n = 95/1,234) occurred with hyperchloremia in the minimum chloride measurement group and the highest AKI rate (7.7%; n = 72/930) occurred with hypochloremia in the initial chloride measurement group. The most common diagnostic categories associated with chloride abnormalities were injury and poisoning; respiratory; central nervous system; infectious and parasitic diseases; and endocrine, nutritional, metabolic, and immunity disorders. Controlled for race, gender, age, and diagnostic categories, mortality odds ratios, and AKI odds ratios were significantly higher for hyperchloremia and hypochloremia compared with normochloremia. In conclusion, hyperchloremia and hypochloremia are independently associated with mortality and AKI in children in the ICU.

Effects of hyperchloremia on renal recovery in critically ill children with acute kidney injury

BACKGROUND

Serum chloride derangements are associated with poor clinical outcomes, including acute kidney injury (AKI) and mortality. We sought to determine the association between persistent hyperchloremia and renal recovery in critically ill children with AKI.

METHODS

We performed a retrospective cohort study of all patients with day 2 AKI admitted to a large academic pediatric intensive care unit from January 2014 to December 2015. After applying exclusion criteria, 348 patients were categorized as (1) hyperchloremia on both day 2 and day 7 (PersistentCl), (2) hyperchloremia on day 2 with normochloremia on day 7 (RecoveredCl), (3) normochloremia on day 2 with hyperchloremia on day 7 (DelayedCl), and (4) no hyperchloremia on day 2 nor day 7 (NormalCl). Hyperchloremia was defined as ≥ 110 mEq/L. The primary outcome was renal recovery on day 7, defined as the absence of AKI criteria. Secondary outcomes included discharge renal recovery, mortality, duration of mechanical ventilation, and hospital length of stay.

RESULTS

Day 7 renal recovery rates for PersistentCl, RecoveredCl, DelayedCl, and NormalCl were 37%, 66%, 71%, and 52% respectively. PersistentCl had lower odds of day 7 renal recovery (aOR = 0.29; 95% CI, 0.14 to 0.60; p = 0.0009), lower odds of discharge renal recovery (aOR = 0.22; 95% CI, 0.11 to 0.48; p = 0.0001), and higher odds of mortality (aOR = 3.50; 95% CI, 1.11 to 11.10; p = 0.03) when compared with RecoveredCl after adjusting for confounders.

CONCLUSIONS

Persistent hyperchloremia is independently associated with impaired renal recovery as well as higher mortality. Prospective studies are indicated to determine if serum chloride represents a modifiable risk factor for poor outcomes. Graphical abstract.

Pragmatic Pediatric Trial of Balanced Versus Normal Saline Fluid in Sepsis: The PRoMPT BOLUS Randomized Controlled Trial Pilot Feasibility Study

BACKGROUND

Resuscitation with crystalloid fluid is a cornerstone of pediatric septic shock treatment. However, the optimal type of crystalloid fluid is unknown. We aimed to determine the feasibility of conducting a pragmatic randomized trial to compare balanced (lactated Ringer's [LR]) with 0.9% normal saline (NS) fluid resuscitation in children with suspected septic shock.

METHODS

Open-label pragmatic randomized controlled trial at a single academic children's hospital from January to August 2018. Eligible patients were >6 months to <18 years old who were treated in the emergency department for suspected septic shock, operationalized as blood culture, parenteral antibiotics, and fluid resuscitation for abnormal perfusion. Screening, enrollment, and randomization were carried out by the clinical team as part of routine care. Patients were randomized to receive either LR or NS for up to 48 hours following randomization. Other than fluid type, all treatment decisions were at the clinical team's discretion. Feasibility outcomes included proportion of eligible patients enrolled, acceptability of enrollment via the U.S. federal exception from informed consent (EFIC) regulations, and adherence to randomized study fluid administration.

RESULTS

Of 59 eligible patients, 50 (85%) were enrolled and randomized. Twenty-four were randomized to LR and 26 to NS. Only one (2%) of 44 patients enrolled using EFIC withdrew before study completion. Total median (interquartile range [IQR]) crystalloid fluid volume received during the intervention window was 107 (60 to 155) mL/kg and 98 (63 to 128) mL/kg in the LR and NS arms, respectively (p = 0.50). Patients randomized to LR received a median (IQR) of only 20% (13 to 32) of all study fluid as NS compared to 99% (64% to 100%) of study fluid as NS in the NS arm (absolute difference = 79%, 95% CI = 48% to 85%).

CONCLUSIONS

A pragmatic study design proved feasible to study comparative effectiveness of LR versus NS fluid resuscitation for pediatric septic shock.

Intravenous Fluid Prescription Practices in Critically Ill Children: A Shift in Focus from Natremia to Chloremia?

Our objective is to evaluate intravenous (IV) fluid prescription practice patterns in critically ill children in the first 72 hours of pediatric intensive care unit (PICU) admission and to evaluate the incidence and predictors of hyperchloremic metabolic acidemia (HCMA) and the association between HCMA and adverse outcomes. This retrospective cohort study was conducted in two tertiary-care Canadian PICUs. Children aged 0 to 18 years admitted to the PICU between January 2015 and January 2016 who received at least 50% of their calculated maintenance fluid requirements parenterally during the first 24 hours of admission were included. Children with known preexisting conditions associated with HCMA, such as renal tubular acidosis and gastrointestinal bicarbonate losses, were excluded. Of the 771 children screened, 543 met eligibility criteria and were included. The commonest prescribed maintenance fluid was 0.9% NaCl (72.9%) followed by lactated Ringer's solution (19.6%) and hypotonic solutions (4.6%). Balanced salt solutions (i.e., lactated Ringer's and Plasma-Lyte) were as commonly administered as unbalanced solutions (0.9% NaCl) for volume expansion (49.6 vs. 48.5%, respectively). Medications contributed to a significant proportion of total daily intake, in excess of bolus fluids. The incidence of hyperchloremia and HCMA was 94.9% (95% confidence interval [CI]: 93.2-96.9; 470/495) and 38.9% (95% CI: 34.6-43.2; 196/504), respectively. Predictors of HCMA were increasing combined bolus and maintenance 0.9% NaCl intake (odds ratio: 1.13; 95% CI: 1.04-1.23) and increasing severity of illness. HCMA was not associated with an increased risk of acute kidney injury, feeding intolerance, or PICU-acquired weakness. Isotonic fluids, specifically 0.9% NaCl, were the most commonly administered maintenance IV fluid in critically ill children. Sources of chloride load are not isolated to resuscitation fluids as previously suggested. Maintenance fluids and fluids administered with medications and IV flushes (fluid creep) are under-recognized significant sources of fluid and electrolyte intake in critically ill children. HCMA is common, and further prospective research is required to determine whether HCMA is indeed harmful in children. However, all significant sources of fluid should be accounted for in the design of future trials comparing balanced and unbalanced salt solutions.

Ab-normal saline in abnormal kidney function: risks and alternatives

Intravenous 0.9% saline has saved countless lives since it was introduced over a century ago. It remains the most widespread crystalloid in both adult and pediatric practice. However, in recent years, evidence of deleterious effects is accruing. These include increased mortality, acute kidney injury (AKI), metabolic acidosis, and coagulopathy. The predominant cause for these sequelae appears to be the excess chloride concentration of 0.9% saline relative to plasma. This has led to development of balanced isotonic solutions such as PlasmaLyte. This review summarizes current evidence for adverse effects of chloride-rich intravenous fluid and considers whether 0.9% saline should still be used in 2018 or abandoned as a historical treatment in favor of balanced crystalloid solutions.

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.