[Effects of different loading solutions on plasma osmolality]

A Hospital-Wide Open-Label Cluster Crossover Pragmatic Comparative Effectiveness Randomized Trial Comparing Normal Saline to Ringer's Lactate: Protocol and Statistical Analysis Plan of The FLUID Trial

BACKGROUND

Normal saline (NS) and Ringer's lactate (RL) are the most common crystalloids given to hospitalized patients. Despite concern about possible harm associated with NS (eg, hyperchloremic metabolic acidosis, impaired kidney function, and death), few large multicenter randomized trials focused on critically ill patients have compared these fluids. Uncertainty exists about the effects of these fluids on clinically important outcomes across all hospitalized patients.

OBJECTIVE

The FLUID trial is a pragmatic, multicenter, 2×2 cluster crossover comparative effectiveness randomized trial that aims to evaluate the effectiveness of a hospital-wide policy that stocks either NS or RL as the main crystalloid fluid in 16 hospitals across Ontario, Canada.

METHODS

All hospitalized adult and pediatric patients (anticipated sample size 144,000 patients) with an incident admission to the hospital over the course of each study period will be included. Either NS or RL will be preferentially stocked throughout the hospital for 12 weeks before crossing to the alternate fluid for the subsequent 12 weeks. The primary outcome is a composite of death and hospital readmission within 90 days of hospitalization. Secondary outcomes include death, hospital readmission, dialysis, reoperation, postoperative reintubation, length of hospital stay, emergency department visits, and discharge to a facility other than home. All outcomes will be obtained from health administrative data, eliminating the need for individual case reports. The primary analysis will use cluster-level summaries to estimate cluster-average treatment effects.

RESULTS

The statistical analysis plan has been prepared "a priori" in advance of receipt of the trial data set from ICES and any analyses.

CONCLUSIONS

We describe the protocol and statistical analysis plan for the evaluation of primary and secondary outcomes for the FLUID trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04512950; https://classic.clinicaltrials.gov/ct2/show/NCT04512950.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51783.

FLUID trial: a hospital-wide open-label cluster cross-over pragmatic comparative effectiveness randomised pilot trial comparing normal saline to Ringer's lactate

OBJECTIVES

Normal saline (NS) and Ringer's lactate (RL) are the most common crystalloids used for fluid therapy. Despite evidence of possible harm associated with NS (eg, hyperchloremic metabolic acidosis, impaired kidney function and death), few large multi-centre randomised trials have evaluated the effect of these fluids on clinically important outcomes. We conducted a pilot trial to explore the feasibility of a large trial powered for clinically important outcomes.

DESIGN

FLUID was a pragmatic pilot cluster randomised cross-over trial.

SETTING

Four hospitals in the province of Ontario, Canada PARTICIPANTS: All hospitalised adult and paediatric patients with an incident admission to the hospital over the course of each study period.

INTERVENTIONS

A hospital wide policy/strategy which stocked either NS or RL throughout the hospital for 12 weeks before crossing over to the alternate fluid for the subsequent 12 weeks.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary feasibility outcome was study fluid protocol adherence. Secondary feasibility outcomes included time to Research Ethics Board (REB) approval and trial initiation. Primary (composite of death or re-admission to hospital in first 90 days of index hospitalisation) and secondary clinical outcomes were analysed descriptively.

RESULTS

Among 24 905 included patients, mean age 59.1 (SD 20.5); 13 977 (56.1%) were female and 21 150 (85.0%) had medical or surgical admitting diagnoses. Overall, 96 821 L were administered in the NS arm, and 78 348 L in the RL arm. Study fluid adherence to NS and RL was 93.7% (site range: 91.6%-98.0%) and 79.8% (site range: 72.5%-83.9%), respectively. Time to REB approval ranged from 2 to 48 days and readiness for trial initiation from 51 to 331 days. 5544 (22.3%) patients died or required hospital re-admission in the first 90 days.

CONCLUSIONS

The future large trial is feasible. Anticipating and addressing logistical challenges during the planning stages will be imperative.

TRIAL REGISTRATION NUMBER

NCT02721485.

FLUID trial: a protocol for a hospital-wide open-label cluster crossover pragmatic comparative effectiveness randomised pilot trial

INTRODUCTION

0.9% saline and Ringer's lactate are the two most common resuscitation crystalloid fluids. 0.9% saline may lead to hyperchloraemic metabolic acidosis and may be associated with impaired kidney function and death. Few large multicentre randomised trials have been conducted to evaluate the effect of these two fluids on clinically important outcomes.

METHODS

FLUID is a pragmatic pilot cluster randomised crossover trial in which four hospitals will be randomised to normal saline or Ringer's lactate for 14 weeks, then crossover to the alternative fluid for the subsequent 14 weeks after 1 to 3 week transition. With waiver of informed consent, all adult and paediatric patients admitted to participating sites will be included in the FLUID trial except for neonates. Primary feasibility outcome is study fluid protocol adherence (target:≥80%). Secondary feasibility outcomes include time to research ethics board (REB) approval and readiness to trial initiation (≤3 months from REB submission and approval). Primary (composite of death or re-admission to hospital in first 90 days of index hospitalisation) and secondary clinical outcomes for the future large FLUID trial will be described. Protocol adherence will be collected by site at specified time points. All clinical data will be obtained at patient level through provincial health administrative data held at the Institute for Clinical Evaluative Sciences (ICES). Event rates for the primary and secondary outcomes will be described using frequencies and proportions with 95% CIs. Intracluster and interperiod correlation coefficients will be calculated from population-level data available at ICES.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Ottawa Health Science Research Ethics Board. The FLUID pilot will determine feasibility, and ICES data across all potential sites in Ontario will allow calculation of sample size parameter estimates to inform the design and implementation of the large trial.

TRIAL REGISTRATION NUMBER

NCT02721485; Pre-results.

Isotonic crystalloid solutions: a structured review of the literature

BACKGROUND

Several different crystalloid solutions are available for i.v. fluid administration but there is little information about their specific advantages and disadvantages.

METHODS

We performed a systematic search of MEDLINE, EMBASE, and CENTRAL up until May 17, 2012, selecting all prospective human studies that directly compared any near-isotonic crystalloids and reported any outcome.

RESULTS

From the 5060 articles retrieved in the search, only 28 met the selection criteria. There was considerable heterogeneity among the studies. Several articles reported an increased incidence of hyperchloraemic acidosis with the use of normal saline, and others an increase in blood lactate levels when large amounts of Ringer's lactate solutions were infused. From the limited data available, normal saline administration appears to be associated with increased blood loss and greater red blood cell transfusion volumes in high-risk populations compared to Ringer's lactate. Possible effects of the different solutions on renal function, inflammatory response, temperature, hepatic function, glucose metabolism, and splanchnic perfusion are also reported. The haemodynamic profiles of all the solutions were similar.

CONCLUSIONS

Different solutions have different effects on acid-base status, electrolyte levels, coagulation, renal, and hepatic function. Whether these differences have clinical consequences remains unclear.

Pediatric neurologic emergencies

Neuroemergencies are life-threatening situations in which, whatever the cause, common pathologic phenomena result in secondary brain lesions. The goal of critical care management is to stop these self-aggravating processes as soon as possible. Initial resuscitation is devoted to control of the airway and hemodynamic and hydroelectrolytic stabilization. With mass lesions, minimal computed tomographic exploration immediately precedes surgical decompression. Further critical care adapted to the child's needs requires multimodal monitoring. Normoventilation, deep sedation, osmotherapy with mannitol or hypertonic saline solutions, and optimization of mean arterial pressure are the basis of management. A purely pressure-driven approach aimed at controlling cerebral perfusion pressure could be potentially harmful, and associated measurement of blood flow velocity with transcranial Doppler and jugular bulb oxygen saturation monitoring allows an approach to cerebral blood flow and metabolism. Outcome can be improved in dangerous situations such as severe brain injuries, cerebral arteriovenous malformation rupture, status epilepticus, and acute hydrocephalus, provided that emergency management could be applied efficiently.