Randomized Clinical Trial of 20% Mannitol Versus 3% Hypertonic Saline in Children With Raised Intracranial Pressure Due to Acute CNS Infections

A narrative review of neuromonitoring modalities in critically ill children

Acute neurologic injury is common in critically ill children. Some conditions - such as traumatic brain injury, meningitis, and hypoxic-ischemic injury following cardiac arrest - require careful consideration of cerebral physiology. Specialized neuromonitoring techniques provide insight regarding patient-specific and disease-specific insight that can improve diagnostic accuracy, aid in targeting therapeutic interventions, and provide prognostic information. In this review, we will discuss recent innovations in invasive (e.g., intracranial pressure monitoring and related computed indices) and noninvasive (e.g., transcranial doppler, near-infrared spectroscopy) neuromonitoring techniques used in traumatic brain injury, central nervous system infections, and after cardiac arrest. We will discuss the pertinent physiological mechanisms interrogated by each technique and discuss available evidence for potential clinical application. We will also discuss the use of innovative neuromonitoring techniques to detect and manage neurologic complications in critically ill children with systemic illness, focusing on sepsis and cardiorespiratory failure requiring extracorporeal membrane oxygenation.

Hypertonic Saline vs. Mannitol in Management of Elevated Intracranial Pressure in Children: A Meta-Analysis

OBJECTIVE

To compare the efficacy and safety of two hyperosmolar agents (hypertonic saline vs. mannitol) used for the reduction of elevated intracranial pressure (ICP) in children.

METHODS

A meta-analysis of randomized controlled trials (RCTs) was conducted and GRADE system (Grading of Recommendations, Assessment, Development and Evaluation) of evidence was applied. Relevant databases were searched till 31st May 2022. Primary outcome was mortality rate.

RESULTS

Of 720 citations retrieved, 4 RCTs were included in the meta-analysis (n = 365, male = 61%). Traumatic and non-traumatic cases of elevated ICP were included. There was no significant difference in the mortality rate between the two groups [relative risk (RR), 1.09; (95% confidence interval (CI), 0.74 to 1.6)]. No significant difference was found for any of the secondary outcomes, except serum osmolality (being significantly higher in mannitol group). Adverse events like shock and dehydration were significantly higher in the mannitol group, and hypernatremia in the hypertonic saline group. The evidence generated for primary outcome was of "low certainty", and for secondary outcomes, it varied from "very-low to moderate certainty".

CONCLUSIONS

There is no significant difference between hypertonic saline and mannitol used for the reduction of elevated ICP in children. The evidence generated for primary outcome (mortality rate) was of "low certainty", and for secondary outcomes, it varied from "very-low to moderate certainty". More data from high-quality RCTs are needed to guide any recommendation.

Effect of continuous infusion of hypertonic saline solution on survival of patients with brain injury: a systematic review and meta-analysis

BACKGROUND

The objective was to determine the effects of continuous infusion of hypertonic saline solutions on outcomes of patients with brain injury.

METHODS

Preferred Reported Items for Systemic Reviews and Meta-Analysis guidelines were followed. We searched the MEDLINE and COCHRANE clinical trials register (through December 2021) and reference lists of articles. We included all clinical trials conducted in brain-injured patients hospitalized in intensive care units evaluating continuous infusion of hypertonic saline solution (osmolarity above 308 mOsm/L). Two reviewers extracted data that were checked by two others. The primary outcome was the in-hospital mortality rate. The main secondary outcomes were the rates of intracranial hypertension, an unfavorable neurological outcome at day 90, and adverse events.

RESULTS

We identified 23 clinical trials reporting the use of continuous infusion of hypertonic saline solution in brain-injured patients. The primary outcome was available in 10 studies (n = 1883 patients). The odds ratio (OR) for in-hospital death with the intervention was 0.68 (95% confidence interval (CI), 0.54-0.85, I² = 0%). In the subgroup of studies including only traumatic brain-injured patients (7 studies, n = 1521 patients), the OR for the primary outcome was 0.74 (95%CI 0.57-0.95) with the intervention. The OR for intracranial hypertension and unfavorable neurological outcome at day 90 were 0.66 (95%CI 0.49-0.88, I² = 42%, n = 787 patients) and 0.61 (95%CI 0.46-0.81, I² = 15%, n = 956 patients), respectively. Regarding safety, the OR of acute kidney injury and severe hypernatremia were 0.82 (95%CI 0.47-1.44, I² = 0%) and 3.38 (95%CI 2.16-5.27, I² = 24%).

CONCLUSIONS

Continuous hypertonic saline solution infusion reduced in-hospital mortality without increasing the risk of unfavorable neurological outcome at day 90 in brain-injured patients hospitalized in intensive care units. Given the inclusion of observational and heterogeneous studies, further randomized studies are needed before developing recommendations for implementation at the bedside.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021221367. Registered 13 May 2021.

Multimodal Neurologic Monitoring in Children With Acute Brain Injury

Children with acute neurologic illness are at high risk of mortality and long-term neurologic disability. Severe traumatic brain injury, cardiac arrest, stroke, and central nervous system infection are often complicated by cerebral hypoxia, hypoperfusion, and edema, leading to secondary neurologic injury and worse outcome. Owing to the paucity of targeted neuroprotective therapies for these conditions, management emphasizes close physiologic monitoring and supportive care. In this review, we will discuss advanced neurologic monitoring strategies in pediatric acute neurologic illness, emphasizing the physiologic concepts underlying each tool. We will also highlight recent innovations including novel monitoring modalities, and the application of neurologic monitoring in critically ill patients at risk of developing neurologic sequelae.

Clinical effects of hypertonic saline boluses in children with severe traumatic brain injury

AIM

To quantify the effects of 3% hypertonic saline (HTS) boluses on intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in children.

METHODS

A retrospective study of patients admitted to a regional neurosurgical children's intensive care unit.

RESULTS

A total of 156 HTS boluses were given to children with traumatic brain injury. ICP decreased 6 mmHg (P < 0.01) and CPP increased 4 mmHg (P = 0.003) 1-h post-bolus. Effects persisted for 3 h post-dose ICP was 5 mmHg lower) and 4 h post-bolus CPP was 3 mmHg higher. ICP change was not associated with pre-bolus serum sodium concentration.

CONCLUSIONS

Hypertonic saline 3% at 5 mL/kg is an effective osmolar therapy for reducing ICP and increasing CPP in children for up to 3 h. '53-53' is a suitable guide - 5 mL/kg of 3% HTS will on average decrease ICP by at least 5 mmHg for 3 h. Pre-bolus serum sodium concentration is not correlated with effect size.

Effects of hypertonic saline on intracranial pressure and cerebral autoregulation in pediatric traumatic brain injury

OBJECTIVE

Hypertonic saline (HTS) is commonly used in children to lower intracranial pressure (ICP) after severe traumatic brain injury (sTBI). While ICP and cerebral perfusion pressure (CPP) correlate moderately to TBI outcome, indices of cerebrovascular autoregulation enhance the correlation of neuromonitoring data to neurological outcome. In this study, the authors sought to investigate the effect of HTS administration on ICP, CPP, and autoregulation in pediatric patients with sTBI.

METHODS

Twenty-eight pediatric patients with sTBI who were intubated and sedated were included. Blood pressure and ICP were actively managed according to the autoregulation index PRx (pressure relativity index to determine and maintain an optimal CPP [CPPopt]). In cases in which ICP was continuously > 20 mm Hg despite all other measures to decrease it, an infusion of 3% HTS was administered. The monitoring data of the first 6 hours after HTS administration were analyzed. The Glasgow Outcome Scale (GOS) score at the 3-month follow-up was used as the primary outcome measure, and patients were dichotomized into favorable (GOS score 4 or 5) and unfavorable (GOS score 1-3) groups.

RESULTS

The mean dose of HTS was 40 ml 3% NaCl. No significant difference in ICP and PRx was seen between groups at the HTS administration. ICP was lowered significantly in all children, with the effect lasting as long as 6 hours. The lowering of ICP was significantly greater and longer in children with a favorable outcome (p < 0.001); only this group showed significant improvement of autoregulatory capacity (p = 0.048). A newly established HTS response index clearly separated the outcome groups.

CONCLUSIONS

HTS significantly lowered ICP in all children after sTBI. This effect was significantly greater and longer-lasting in children with a favorable outcome. Moreover, HTS administration restored disturbed autoregulation only in the favorable outcome group. This highlights the role of a "rescuable" autoregulation regarding outcome, which might be a possible indicator of injury severity. The effect of HTS on autoregulation and other possible mechanisms should be further investigated.

Application of bench studies at the bedside to improve outcomes in the management of severe diabetic ketoacidosis in children-a narrative review

OBJECTIVE

In this review, we address a few key issues and the challenges faced in the management of severe diabetic ketoacidosis (DKA) in children, highlighting the existing standard of care, supported by evidence and bench studies.

BACKGROUND

The classic triad of DKA namely hyperglycemia, metabolic acidosis and ketonemia warrants immediate attention with fluids and insulin. Correction of dehydration in DKA is of utmost priority and the calculation of fluid volume and choice of fluid have remained a matter of debate. Insulin therapy, to halt the ketone production, in DKA has undergone wide variations in dose and preparation since its discovery. Although the mortality due to severe DKA has remarkably decreased, complications like cerebral edema and acute kidney injury (AKI) continue to haunt the intensivists and endocrinologists on a few occasions.

METHODS

We have selected a few important questions in the management of severe DKA in children, addressing the challenges, reviewing the studies, guidelines and bedside practices with evidence in this narrative review.

CONCLUSIONS

The focus of management should be to understand and normalise the deranged physiology rather than trying to get normal laboratory reports. This needs careful understanding of the pathogenesis and deriving conclusion from bench studies. With newer studies and evidence, guidelines are revised every few years. There is a trend towards more conservative therapy, with continuous and advanced monitoring. Switching to subcutaneous insulin and oral hydration is done as early as possible with clinical monitoring and resolution of DKA. Management of severe DKA in children can vary from simple fluid titration and insulin infusion in mild cases to a scenario with multiorgan dysfunction requiring intensive monitoring and advanced organ support. Individualisation of therapy to suit the needs with the available evidence and expertise is extremely essential.