Hypertonic saline and its effect on intracranial pressure, cerebral perfusion pressure, and brain tissue oxygen

Comparing the effects of mannitol and hypertonic saline in severe traumatic brain injury patients with elevated intracranial pressure: a systematic review and meta-analysis

OBJECTIVES

Controlling elevated intracranial pressure following brain injury with hyperosmolar agents is one of the mainstay treatments in traumatic brain injury patients. In this study, we compared the effects of hypertonic saline (HS) and mannitol in reducing increased intracranial pressure.

METHODS

A total of 637 patients from 15 studies were included in our meta-analysis. The primary outcomes were mortality, the length of stay in the hospital and ICU, and the Glasgow Outcome Scale at follow-up.

RESULTS

The mortality in the mannitol group was not statistically different compared to the HS group (RR = 1.55; 95% CI = [0.98, 2.47], p = 0.06). The length of stay in the ICU was significantly shorter in the HS group (MD = 1.18, 95% CI = [0.44, 1.92], p < 0.01). In terms of favorable neurological outcomes, there was no significant difference between the two agents (RR = 0.92, 95% CI = [0.11, 7.96], p = 0.94). The duration of the effect was shorter in the mannitol group than in the HS group (MD = -0.67, 95% CI = [-1.00, -0.33], p < 0.01).

DISCUSSION

The results showed that HS and mannitol had similar effects in reducing ICP. Although the HS was associated with a longer duration of effect and shorter ICU stay, other secondary outcomes including mortality rate and favorable neurological outcomes were similar between the two drugs. In conclusion, considering the condition of each patient individually, HS could be a reasonable option than mannitol to reduce ICP in TBI patients.

Comparing equiosmolar hypertonic saline and mannitol for achieving brain relaxation in elective craniotomy patients: A systematic review and meta-analysis

Background

This study strives to provide a current and thorough assessment of the comparative efficacy and safety between equiosmolar quantities of hypertonic saline (HS) and mannitol in facilitating brain relaxation for patients undergoing elective craniotomies.

Methods

This systematic review and meta-analysis, following preferred reporting items for systematic reviews and meta-analyses guidelines, compared the efficacy and safety of equiosmolar concentrations of mannitol and HS in elective craniotomies. PubMed, Scopus, Cochrane Library, ScienceDirect, and Proquest databases were searched using keywords related to mannitol, HS, and craniotomy. Results were analyzed through a random-effects model using Mantel-Haenszel risk ratio and standard mean difference. P < 0.05 was considered significant.

Results

Thirteen randomized controlled trials encompassing 965 patients (516 in the HS group and 448 in the mannitol group) were analyzed. The quality of studies was moderate-to-high, and no significant publication bias was observed. The primary outcome, brain relaxation, favored HS over mannitol without significant heterogeneity. Mannitol was associated with increased urine output compared to HS, irrespective of dose, with high heterogeneity. HS was linked to significantly reduced fluid input, confirmed by subgroup analysis with lower heterogeneity. No significant difference was found in serum osmolality between the two agents. Serum sodium (Na+) levels favored HS, whereas arterial blood Na+ levels also favored HS despite considerable heterogeneity. Maximum mean arterial pressure was higher with HS, but it displayed significant heterogeneity. Maximum central venous pressure showed no significant difference between the two agents, with moderate heterogeneity.

Conclusion

HS appears more effective than mannitol in achieving brain relaxation, and it may offer advantages in fluid management and Na+ balance. Clinicians should consider these findings when selecting hyperosmotic agents for neurosurgical procedures. Further research is needed to address heterogeneity in certain outcomes and guide clinical practice.

Evaluation of the Safety of Slow IV Push Versus Slow IV Infusion Administration of 23.4% Sodium Chloride

Background and Purpose

Increased intracranial pressure due to cerebral edema is a medical emergency in which 23.4% sodium chloride (23.4% NaCl) may be a lifesaving intervention. Currently, safety data is limited on slow IV push (IVP) administration. The purpose of this study was to evaluate the safety of IVP administration of 23.4% NaCl and determine the number of infusion-related adverse events (IRAEs) compared to slow IV infusion (SIV) administration.

Methods

We performed a retrospective review of patients who received a dose of 23.4% NaCl at the (removed institution) from January 2015 to June 2020 as either SIV over 30 minutes or IVP over 2-5 minutes.

Results

In total, 81 patients, 55 in the IVP group and 26 in the SIV group, were included in the analysis. There was a significantly faster time from order entry to dose completion (IVP 25 [13,58] vs SIV 73 [55,113] minutes, P < .001). There was no difference in IRAEs between the groups (IVP 17 [31%] vs SIV 6 [23%], P = .466). Hypotension was most common (IVP 13 [24%] vs SIV 5 [19%], P = .656) followed by bradycardia (IVP 6 [11%] vs SIV 1 [4%], P = .291). There were no extravasations reported.

Conclusions

Overall, among a cohort of patients with cerebral edema, we found no difference in the incidence of IRAEs between SIV and IVP administration of 23.4% NaCl, and found a faster time to complete administration fssor the latter. In emergent scenarios where time may impact neurologic function, 23.4% NaCl administered IVP may be an alternative to SIV administration.

Safety and Effect on Intracranial Pressure of 3% Hypertonic Saline Bolus Via Peripheral Intravenous Catheter for Neurological Emergencies

BACKGROUND

Elevated intracranial pressure (ICP) is a neurological emergency in patients with acute brain injuries. Such a state requires immediate and effective interventions to prevent potential neurological deterioration. Current clinical guidelines recommend hypertonic saline (HTS) and mannitol as first-line therapeutic agents. Notably, HTS is conventionally administered through central venous catheters (CVCs), which may introduce delays in treatment due to the complexities associated with CVC placement. These delays can critically affect patient outcomes, necessitating the exploration of more rapid therapeutic avenues. This study aimed to investigate the safety and effect on ICP of administering rapid boluses of 3% HTS via peripheral intravenous (PIV) catheters.

METHODS

A retrospective cohort study was performed on patients admitted to Sisters of Saint Mary Health Saint Louis University Hospital from March 2019 to September 2022 who received at least one 3% HTS bolus via PIV at a rate of 999 mL/hour for neurological emergencies. Outcomes assessed included complications related to 3% HTS bolus and its effect on ICP.

RESULTS

Of 216 3% HTS boluses administered in 124 patients, complications occurred in 8 administrations (3.7%). Pain at the injection site (4 administrations; 1.9%) and thrombophlebitis (3 administrations; 1.4%) were most common. The median ICP reduced by 6 mm Hg after 3% HTS bolus administration (p < 0.001).

CONCLUSIONS

Rapid bolus administration of 3% HTS via PIV catheters presents itself as a relatively safe approach to treat neurological emergencies. Its implementation could provide an invaluable alternative to the traditional CVC-based administration, potentially minimizing CVC-associated complications and expediting life-saving interventions for patients with neurological emergencies, especially in the field and emergency department settings.

Fluid therapy and traumatic brain injury: A narrative review

Traumatic brain injury (TBI) is an important health and social problem. The mechanism of damage of this entity could be divided into two phases: (1) a primary acute injury because of the traumatic event; and (2) a secondary injury due to the hypotension and hypoxia generated by the previous lesion, which leads to ischemia and necrosis of neural cells. Cerebral edema is one of the most important prognosis markers observed in TBI. In the early stages of TBI, the cerebrospinal fluid compensates the cerebral edema. However, if edema increases, this mechanism fails, increasing intracranial pressure. To avoid this chain effect, several treatments are applied in the clinical practice, including elevation of the head of the bed, maintenance of normothermia, pain and sedation drugs, mechanical ventilation, neuromuscular blockade, controlled hyperventilation, and fluid therapy (FT). The goal of FT is to improve the circulatory system to avoid the lack of oxygen to organs. Therefore, rapid and early infusion of large volumes of crystalloids is performed in clinical practice to restore blood volume and blood pressure. Despite the relevance of FT in the early management of TBI, there are few clinical trials regarding which solution is better to apply. The aim of this study is to provide a narrative review about the role of the different types of FT used in the daily clinical practice on the management of TBI. To achieve this objective, a physiopathological approach to this entity will be also performed, summarizing why the different types of FT are used.

Comparison of Equiosmolar Doses of 7.5% Hypertonic Saline and 20% Mannitol on Cerebral Oxygenation Status and Release of Brain Injury Markers During Supratentorial Craniotomy: A Randomized Controlled Trial

BACKGROUND

Hyperosmolar therapy is the mainstay of treatment to reduce brain bulk and optimize surgical exposure during craniotomy. This study investigated the effect of equiosmolar doses of 7.5% hypertonic saline (HTS) and 20% mannitol on intraoperative cerebral oxygenation and metabolic status, systemic hemodynamics, brain relaxation, markers of cerebral injury, and perioperative craniotomy outcomes.

METHODS

A total of 51 patients undergoing elective supratentorial craniotomy were randomly assigned to receive 7.5% HTS (2 mL/kg) or 20% mannitol (4.6 mL/kg) at scalp incision. Intraoperative arterial and jugular bulb blood samples were collected at predefined time intervals for assessment of various indices of cerebral oxygenation; multiple hemodynamic variables were concomitantly recorded. S100B protein and neuron-specific enolase levels were determined at baseline, and at 6 and 12 hours after surgery for assessment of neuronal injury. Brain relaxation and perioperative outcomes were also assessed.

RESULTS

Demographic and intraoperative data, brain relaxation score, and perioperative outcomes were comparable between groups. Jugular bulb oxygen saturation and partial pressure of oxygen, arterial-jugular oxygen and carbon dioxide differences, and brain oxygen extraction ratio were favorably affected by 7.5% HTS up to 240 minutes postinfusion ( P <0.05), whereas mannitol was associated with only a short-lived (up to 15 min) improvement of these indices ( P <0.05). The changes in cerebral oxygenation corresponded to transient expansion of intravascular volume and improvements of cardiovascular performance. Increases in S100B and neuron-specific enolase levels at 6 and 12 hours after surgery ( P <0.0001) were comparable between groups.

CONCLUSIONS

The conclusion is that 7.5% HTS has a more beneficial effect on cerebral oxygenation than an equiosmolar dose of 20% mannitol during supratentorial craniotomy, yet no clear-cut clinical superiority of either solution could be demonstrated.

Hypertonic saline for traumatic brain injury: a systematic review and meta-analysis

BACKGROUND

Traumatic brain injury (TBI) causes mortality and long-term disability among young adults and imposes a notable cost on the healthcare system. In addition to the first physical hit, secondary injury, which is associated with increased intracranial pressure (ICP), is defined as biochemical, cellular, and physiological changes after the physical injury. Mannitol and Hypertonic saline (HTS) are the treatment bases for elevated ICP in TBI. This systematic review and meta-analysis evaluates the effectiveness of HTS in the management of patients with TBI.

METHODS

This study was conducted following the Joanna Briggs Institute (JBI) methods and PRISMA statement. A systematic search was performed through six databases in February 2022, to find studies that evaluated the effects of HTS, on increased ICP. Meta-analysis was performed using comprehensive meta-analysis (CMA).

RESULTS

Out of 1321 results, 8 studies were included in the systematic review, and 3 of them were included in the quantitative synthesis. The results of the meta-analysis reached a 35.9% (95% CI 15.0-56.9) reduction in ICP in TBI patients receiving HTS, with no significant risk of publication bias (t-value = 0.38, df = 2, p-value = 0.73). The most common source of bias in our included studies was the transparency of blinding methods for both patients and outcome assessors.

CONCLUSION

HTS can significantly reduce the ICP, which may prevent secondary injury. Also, based on the available evidence, HTS has relatively similar efficacy to Mannitol, which is considered the gold standard therapy for TBI, in boosting patients' neurological condition and reducing mortality rates.

Safety and Tolerability of 23.4% Hypertonic Saline Administered Over 2 to 5 Minutes for the Treatment of Cerebral Herniation and Intracranial Pressure Elevation

BACKGROUND

Hyperosmolar therapy is the cornerstone of medical management of sustained elevated intracranial pressure from cerebral edema. Acute intracranial hypertension and herniation is a medical emergency that requires rapid treatment and stabilization to prevent secondary brain injury or death. Intravenous hypertonic sodium chloride (NaCl) 23.4% is an effective treatment modality commonly used in this setting. Because of its high osmolarity, use has historically been limited primarily to central venous line administration as an intermittent infusion due to concerns about thrombophlebitis, injection site pain, and tissue necrosis or injury with extravasation. The objective of this analysis was to prospectively evaluate the safety of administration of 23.4% NaCl as a rapid intravenous push over 2-5 min.

METHODS

A prospective analysis of patients admitted between April 2021 and December 2021 who received 23.4% NaCl intravenous push over 2-5 min in a central or peripheral line was performed. Safety end points included incidence of new onset hypotension [defined as systolic blood pressure (SBP) < 90 mm Hg or SBP decrease of at least 20 mm Hg], bradycardia (defined as heart rate < 50 beats per minute), and infusion site reactions documented within 1 h of administration. For secondary safety outcomes, highest and lowest SBP and lowest heart rates documented within 1 h before 23.4% NaCl administration were compared with values collected within 1 h post administration and evaluated by mixed-design analysis of variance test with adjustment for peripheral versus central line administration.

RESULTS

We identified 32 patients who received 79 administrations of 23.4% NaCl through a central line or peripheral line during the study period. An SBP decrease of at least 20 mm Hg was observed in 13% of patients, an SBP < 90 mm Hg occurred in 16% of patients, and bradycardia occurred in 3% of patients who received 23.4% NaCl. Injection site pain was reported by one patient without documented thrombophlebitis, cellulitis, or tissue damage. Pain was not reported during two subsequent administrations in the same patient. There was no documented occurrence of soft tissue injury or necrosis in any patient. Compared with baseline vital signs before 23.4% NaCl administration, no difference in vital signs post administration was observed.

CONCLUSIONS

Central and peripheral administration of 23.4% NaCl over 2-5 min was well tolerated, and incidence of hypotension, bradycardia, or infusion site-related adverse events was rare.

Assessing the Impact of 3% Hypertonic Saline Hyperosmolar Therapy on Intubated Children With Isolated Traumatic Brain Injury by Cerebral Oximetry in a Pediatric Emergency Setting

BACKGROUND

Intubated pediatric patients with isolated traumatic brain injury (TBI) are a diagnostic challenge for early detection of altered cerebral physiology instigated by trauma-induced increased intracranial pressure (ICP) while preventing secondary neuronal damage (secondary insult detection) and assessing the effects of increased ICP therapeutic interventions (3% hypertonic saline [HTS]). Invasive brain tissue oxygen monitoring is guiding new intensive care unit TBI management but is not pediatric emergency department (PED) readily accessible. Objective measurements on pediatric isolated TBI-altered bihemispheric cerebral physiology and treatment effects of 3% HTS are currently lacking. Cerebral oximetry can assess increased ICP-induced abnormal bihemispheric cerebral physiology by measuring regional tissue oxygenation (rcSO2) and cerebral blood volume index (CBVI) and the mechanical cerebrospinal fluid removal effects on the increased ICP-induced abnormal bihemispheric cerebral physiology.In the PED intubated patients with isolated TBI, assessing the 3% HTS therapeutic response is solely by vital signs and limited clinical assessment skills. Objective measurements of the 3% HTS hyperosmolar effects on the PED isolated TBI patients' altered bihemispheric cerebral physiology are lacking. We believe that bihemispheric rcSO2 and CBVI could elucidate similar data on 3% HTS impact and influence in the intubated isolated TBI patients.

OBJECTIVE

This study aimed to analyze the effects of 3% HTS on bihemispheric rcSO2 and CBVI in intubated patients with isolated TBI.

METHODS

An observational, retrospective analysis of bihemispheric rcSO2 and CBVI readings in intubated pediatric patients with isolated TBI receiving 3% HTS infusions, was performed.

RESULTS

From 2010 to 2017, 207 intubated patients with isolated TBI received 3% HTS infusions (median age, 2.9 [1.1-6.9 years]; preintubation Glasgow Coma Scale score, 7 [6-8]). The results were as follows: initial pre-3% HTS, 43% (39.5% to 47.5%; left) and 38% (35% to 42%; right) for rcSO2 < 60%, and 8 (-28 to 21; left) and -15 (-34 to 22; right) for CBVI; post-3% HTS, 68.5% (59.3% to 76%, P < 0.0001; left) and 62.5% (56.0% to 74.8%, P < 0.0001; right) for rcSO2 < 60%, and 12 (-7 to 24, P = 0.04; left) and 14 (-21 to 22, P < 0.0001; right) for CBVI; initial pre-3% HTS, 90% (83% to 91%; left) and 87% (82% to 92%; right) for rcSO2 > 80%, and 16.5 (6 to 33, P < 0.0001; left) and 16.8 (-2.5 to 27.5, P = 0.005; right) for CBVI; and post-3% HTS, 69% (62% to 72.5%, P < 0.0001; left) and 63% (59% to 72%, P < 0.0001; right) for rcSO2 > 80%, and 16.5 (6 to 33, P < 0.0001; left) and 16.8 (-2.5 to 27.5, P = 0.005; right) for CBVI. The following results for cerebral pathology pre-3% HTS were as follows: epidural: 85% (58% to 88.5%) for left rcSO2 and -9.25 (-34 to 19) for left CBVI, and 85.5% (57.5% to 89%) for right rcSO2 and -12.5 (-21 to 27) for CBVI; subdural: 45% (38% to 54%) for left rcSO2 and -9.5 (-25 to 19) for left CBVI, and 40% (33% to 49%) for right rcSO2 and -15 (-30.5 to 5) for CBVI. The following results for cerebral pathology post-3% HTS were as follows: epidural: 66% (58% to 69%, P = 0.03) for left rcSO2 and 15 (-1 to 21, P = 0.0004) for left CBVI, and 63% (52% to 72%, P = 0.009) for right rcSO2, and 15.5 (-22 to 24, P = 0.02) for CBVI; subdural: 63% (56% to 72%, P < 0.0001) for left rcSO2 and 9 (-20 to 22, P < 0.0001) for left CBVI, and 62.5% (48% to 73%, P < 0.0001) for right rcSO2, and 3 (-26 to 22, P < 0.0001) for CBVI. Overall, heart rate showed no significant change. Three percent HTS effect on interhemispheric rcSO2 difference >10 showed rcSO2 < 60%, and subdural hematomas had the greatest reduction (P < 0.001). The greatest positive changes occurred in bihemispheric or one-hemispheric rcSO2 < 60% with an interhemispheric discordance rcSO2 > 10 and required the greatest number of 3% HTS infusions. For 3% HTS 15% rcSO2 change time effect, all patients achieved positive change with subdural hematomas and hemispheric rcSO2 readings <60% with the shortest achievement time of 1.2 minutes (0.59-1.75; P < 0.001).

CONCLUSIONS

In intubated pediatric patients with isolated TBI who received 3% HTS infusions, bihemispheric rcSO2 and CBVI readings immediately detected and trended the 3% HTS effects on the trauma-induced cerebral pathophysiology. The 3% HTS infusion produced a significant improvement in rcSO2 and CBVI readings and a reduction in interhemispheric rcSO2 discordance differences. In patients with bihemispheric or one-hemispheric rcSO2 readings <60% with or without an interhemispheric discordance, rcSO2 > 10 demonstrated the greatest significant positive delta change and required the greatest numbers of 3% HTS infusions. Overall, 3% HTS produced a significant positive 15% change within 2.1 minutes of infusion, whereas heart rate showed no significant change. During trauma neuroresuscitation, especially in intubated isolated TBI patients requiring 3% HTS, cerebral oximetry has shown its functionality as a rapid adjunct neurological, therapeutic assessment tool and should be considered in the initial emergency department pediatric trauma neurological assessment and neuroresuscitation regimen.

Safety of treating acute liver injury and failure

INTRODUCTION

Acute liver injury and progression to acute liver failure can be life-threatening conditions that require prompt careful clinical assessment and therapeutic management.

AREAS COVERED

The aim of this article is to review the safety and side effect profile of pharmacological therapies used in the treatment of acute liver injury with specific focus on hepatic toxicity. We performed an extensive literature search with the terms 'acute liver injury,' 'acute liver failure,' 'therapy,' 'safety,' 'adverse reactions' and 'drug induced liver injury.' A thorough discussion of the main drugs and devices used in patients with acute liver injury and acute liver failure, its safety profile and the management of complications associated to therapy of these conditions is presented.

EXPERT OPINION

Several pharmacological approaches are used in acute liver injury and acute liver failure in an empirical basis. Whilst steroids are frequently tried in serious drug-induced liver injury there is concern on a potential harmful effect of these agents because of the higher mortality in patients receiving the drug; hence, statistical approaches such as propensity score matching might help resolve this clinical dilemma. Likewise, properly designed clinical trials using old and new drugs for subjects with serious drug-induced liver injury are clearly needed.

Safety and Efficacy of 23.4% Sodium Chloride Administered via Peripheral Venous Access for the Treatment of Cerebral Herniation and Intracranial Pressure Elevation

BACKGROUND

Sodium chloride (NaCl) 23.4% solution has been shown to reduce intracranial pressure (ICP) and reverse transtentorial herniation. A limitation of 23.4% NaCl is its high osmolarity (8008 mOsm/l) and the concern for tissue injury or necrosis following extravasation when administered via peripheral venous access. The use of this agent is therefore often limited to central venous or intraosseous routes of administration. Our objective was to evaluate the safety and efficacy of administration of 23.4% NaCl via peripheral venous access compared with administration via central venous access.

METHODS

We reviewed pharmacy records to identify all administrations of 23.4% NaCl at our institution between December 2017 and February 2020. Medical records were then reviewed to identify complications, such as extravasation, soft tissue injury or necrosis, hypotension (mean arterial pressure less than 65 mm Hg), pulmonary edema, hemolysis, and osmotic demyelination. We also compared the change in physiological variables, such as ICP, mean arterial pressure, cerebral perfusion pressure, and heart rate, as well as laboratory values, such as sodium, chloride, bicarbonate, creatinine, and hemoglobin, following administration of 23.4% NaCl via the peripheral and central venous routes.

RESULTS

We identified 299 administrations of 23.4% NaCl (242 central and 57 peripheral) in 141 patients during the study period. There was no documented occurrence of soft tissue injury or necrosis in any patient. One patient developed hypotension following central administration. Among the 38 patients with ICP monitoring at the time of drug administration, there was no significant difference in median ICP reduction (- 13 mm Hg [central] vs. - 24 mm Hg [peripheral], p = 0.21) or cerebral perfusion pressure augmentation (16 mm Hg [central] vs. 15 mm Hg [peripheral], p = 0.87) based on route of administration.

CONCLUSIONS

Peripheral venous administration of 23.4% NaCl is safe and achieves a reduction in ICP equivalent to that achieved by administration via central venous access.

Brain Herniation and Intracranial Hypertension

This article introduces the basic concepts of intracranial physiology and pressure dynamics. It also includes discussion of signs and symptoms and examination and radiographic findings of patients with acute cerebral herniation as a result of increased as well as decreased intracranial pressure. Current best practices regarding medical and surgical treatments and approaches to management of intracranial hypertension as well as future directions are reviewed. Lastly, there is discussion of some of the implications of critical medical illness (sepsis, liver failure, and renal failure) and treatments thereof on causation or worsening of cerebral edema, intracranial hypertension, and cerebral herniation.

Effects of two different doses of 3% hypertonic saline with mannitol during decompressive craniectomy following traumatic brain injury: A prospective, controlled study

Background and Aims:

The current study was designed to compare the effects of two different doses of 3% hypertonic saline with mannitol on intraoperative events during decompressive craniectomy in traumatic brain injury (TBI). Primary outcome measures included assessment of intraoperative brain relaxation, hemodynamic variables, and serum electrolytes. Effect on the postoperative outcome, in terms of the Glasgow coma scale (GCS), length of stay in the ICU, and mortality were the secondary outcome measures.

Material and Methods:

Ninety patients with TBI undergoing craniotomy were enrolled. Patients were assigned to receive 300 mL (328 mOsm) of mannitol (n = 26, M) only or 300 mL of mannitol with 150 mL (482 mOsm) of 3% HS (n = 35, HS₁) or with 300 mL (636 mOsm) of 3% HS (n = 29, HS₂). Brain relaxation was assessed and if required, a rescue dose of mannitol (150 mL) was given. GCS was assessed preoperatively, 24 h postoperatively, and at the time of discharge from the ICU and total duration of stay was noted.

Results:

Acceptable brain relaxation was observed in 89.66% (n = 26, HS₂) and 80% (n = 28, HS₁) patients as compared to 46.1% (n = 12, M) patients (P < 0.001) with significantly less number of patients requiring rescue doses of mannitol in groups HS₁ and HS₂(n = 7 and 3, respectively) as compared to group M (n = 14) (P < 0.05). There was a significant improvement in GCS at 24 h and at the time of discharge from the ICU in patients with a severe head injury in group HS₂ (P = 0.029). In patients with moderate head injury there was a significant improvement in GCS at the time of discharge among all the three groups (P < 0.05).

Conclusion:

Increasing osmotic load by addition of 3% HS to mannitol provides better intraoperative brain relaxation than mannitol alone during decompressive craniectomy. An addition of 300mL 3% HS was found to be more effective in improving GCS in patients with severe TBI.

Escalate and De-Escalate Therapies for Intracranial Pressure Control in Traumatic Brain Injury

Severe traumatic brain injury (TBI) is frequently associated with an elevation of intracranial pressure (ICP), followed by cerebral perfusion pressure (CPP) reduction. Invasive monitoring of ICP is recommended to guide a step-by-step “staircase approach” which aims to normalize ICP values and reduce the risks of secondary damage. However, if such monitoring is not available clinical examination and radiological criteria should be used. A major concern is how to taper the therapies employed for ICP control. The aim of this manuscript is to review the criteria for escalating and withdrawing therapies in TBI patients. Each step of the staircase approach carries a risk of adverse effects related to the duration of treatment. Tapering of barbiturates should start once ICP control has been achieved for at least 24 h, although a period of 2–12 days is often required. Administration of hyperosmolar fluids should be avoided if ICP is normal. Sedation should be reduced after at least 24 h of controlled ICP to allow neurological examination. Removal of invasive ICP monitoring is suggested after 72 h of normal ICP. For patients who have undergone surgical decompression, cranioplasty represents the final step, and an earlier cranioplasty (15–90 days after decompression) seems to reduce the rate of infection, seizures, and hydrocephalus.

Comparison of Weight-Based Dosing versus Fixed Dosing of 23.4% Hypertonic Saline for Intracranial Pressure Reduction in Patients with Severe Traumatic Brain Injury

Context:

Hypertonic saline (HTS) is a pharmacologic therapy used in patients with severe traumatic brain injuries to decrease intracranial pressure (ICP) associated with cerebral edema.

Aims:

The purpose of this study was to compare ICP reduction between fixed doses of 23.4% HTS and weight-based doses.

Setting and Design:

This was a retrospective study that included adult patients at a level 1 trauma center who had nonpenetrating traumatic brain injury, an ICP monitor, and received at least one dose of 23.4% HTS.

Subjects and Methods:

Doses were classified as either high weight-based (>0.6 ml/kg), low weight-based (<0.6 ml/kg), or standard fixed dose (30 ml). Only doses given within 5 days post-injury were evaluated. Percent reduction in ICP was compared pre- and post-dose between dosing groups, and each dose was evaluated as a separate episode.

Statistical Analysis:

The primary and secondary endpoints for the study were analyzed using mixed-model, repeated-measures analysis of covariance.

Results:

A total of 97 doses of HTS were evaluated. The primary endpoint of ICP reduction showed a 42.5% decrease in ICP after the administration of a high weight-based dose, a 36.7% reduction after a low weight-based dose, and a 31.5% reduction after a fixed dose. There was no significant relationship between dose group and percent change in ICP (P = 0.25). A sub-analysis of doses received within 48 h postinjury found a significant relationship between both dose group and percent change in ICP, and initial ICP and percent change in ICP (P = 0.04, and <0.0001 respectively).

Conclusions:

Our data did not show a significant difference between fixed- and weight-based doses of 23.4% HTS for ICP reduction.

Hypertonic Saline is Superior to Mannitol for the Combined Effect on Intracranial Pressure and Cerebral Perfusion Pressure Burdens in Patients With Severe Traumatic Brain Injury

BACKGROUND

Hypertonic saline (HTS) and mannitol are effective in reducing intracranial pressure (ICP) after severe traumatic brain injury (TBI). However, their simultaneous effect on the cerebral perfusion pressure (CPP) and ICP has not been studied rigorously.

OBJECTIVE

To determine the difference in effects of HTS and mannitol on the combined burden of high ICP and low CPP in patients with severe TBI.

METHODS

We performed a case-control study using prospectively collected data from the New York State TBI-trac® database (Brain Trauma Foundation, New York, New York). Patients who received only 1 hyperosmotic agent, either mannitol or HTS for raised ICP, were included. Patients in the 2 groups were matched (1:1 and 1:2) for factors associated with 2-wk mortality: age, Glasgow Coma Scale score, pupillary reactivity, hypotension, abnormal computed tomography scans, and craniotomy. Primary endpoint was the combined burden of ICPhigh (> 25 mm Hg) and CPPlow (< 60 mm Hg).

RESULTS

There were 25 matched pairs for 1:1 comparison and 24 HTS patients matched to 48 mannitol patients in 1:2 comparisons. Cumulative median osmolar doses in the 2 groups were similar. In patients treated with HTS compared to mannitol, total number of days (0.6 ± 0.8 vs 2.4 ± 2.3 d, P < .01), percentage of days with (8.8 ± 10.6 vs 28.1 ± 26.9%, P < .01), and the total duration of ICPhigh + CPPlow (11.12 ± 14.11 vs 30.56 ± 31.89 h, P = .01) were significantly lower. These results were replicated in the 1:2 match comparisons.

CONCLUSION

HTS bolus therapy appears to be superior to mannitol in reduction of the combined burden of intracranial hypertension and associated hypoperfusion in severe TBI patients.

Guidelines for the Acute Treatment of Cerebral Edema in Neurocritical Care Patients

BACKGROUND

Acute treatment of cerebral edema and elevated intracranial pressure is a common issue in patients with neurological injury. Practical recommendations regarding selection and monitoring of therapies for initial management of cerebral edema for optimal efficacy and safety are generally lacking. This guideline evaluates the role of hyperosmolar agents (mannitol, HTS), corticosteroids, and selected non-pharmacologic therapies in the acute treatment of cerebral edema. Clinicians must be able to select appropriate therapies for initial cerebral edema management based on available evidence while balancing efficacy and safety.

METHODS

The Neurocritical Care Society recruited experts in neurocritical care, nursing, and pharmacy to create a panel in 2017. The group generated 16 clinical questions related to initial management of cerebral edema in various neurological insults using the PICO format. A research librarian executed a comprehensive literature search through July 2018. The panel screened the identified articles for inclusion related to each specific PICO question and abstracted necessary information for pertinent publications. The panel used GRADE methodology to categorize the quality of evidence as high, moderate, low, or very low based on their confidence that the findings of each publication approximate the true effect of the therapy.

RESULTS

The panel generated recommendations regarding initial management of cerebral edema in neurocritical care patients with subarachnoid hemorrhage, traumatic brain injury, acute ischemic stroke, intracerebral hemorrhage, bacterial meningitis, and hepatic encephalopathy.

CONCLUSION

The available evidence suggests hyperosmolar therapy may be helpful in reducing ICP elevations or cerebral edema in patients with SAH, TBI, AIS, ICH, and HE, although neurological outcomes do not appear to be affected. Corticosteroids appear to be helpful in reducing cerebral edema in patients with bacterial meningitis, but not ICH. Differences in therapeutic response and safety may exist between HTS and mannitol. The use of these agents in these critical clinical situations merits close monitoring for adverse effects. There is a dire need for high-quality research to better inform clinicians of the best options for individualized care of patients with cerebral edema.

Concentrated hypertonic saline in severe pediatric traumatic brain injury

OBJECTIVE

Describe outcomes associated with bolus and continuous infusions of hypertonic saline (HTS) in children with severe traumatic brain injury (TBI).

METHODS

IRB-approved, single-center, retrospective review of children admitted between January 1, 2012 to August 30, 2018 with a diagnosis of severe TBI who received HTS.

RESULTS

Forty-five children (age 9.3 ± 5.8 yr; 60% male) met inclusion criteria. One-hundred eighty-nine equiosmolar bolus doses of HTS were administered to 43 patients (3% HTS, n = 84 doses; 6% HTS, n = 38 doses; 12% HTS, n = 67 doses) for episodes of acute intracranial hypertension (pressure above 20 mmHg). Significant reductions in ICP were observed at 30, 60, and 120 min following HTS boluses with the greatest decrease observed in patients receiving 12%. Thirty-four patients received a continuous infusion of HTS. Higher concentrations of HTS were associated with a more favorable fluid balance (p < .001), fewer episodes of pulmonary edema (p = .003), and higher intake of protein and energy (p < .001).

CONCLUSIONS

Equiosmolar bolus doses of concentrated HTS were associated with significant reductions in ICP. Benefits of higher concentrations of continuous HTS may include improved fluid balance, less pulmonary edema, and greater amounts of protein and energy intake.

Management of moderate and severe traumatic brain injury

Traumatic brain injury (TBI) is a common disorder with high morbidity and mortality, accounting for one in every three deaths due to injury. Older adults are especially vulnerable. They have the highest rates of TBI-related hospitalization and death. There are about 2.5 to 6.5 million US citizens living with TBI-related disabilities. The cost of care is very high. Aside from prevention, little can be done for the initial primary injury of neurotrauma. The tissue damage incurred directly from the inciting event, for example, a blow to the head or bullet penetration, is largely complete by the time medical care can be instituted. However, this event will give rise to secondary injury, which consists of a cascade of changes on a cellular and molecular level, including cellular swelling, loss of membrane gradients, influx of immune and inflammatory mediators, excitotoxic transmitter release, and changes in calcium dynamics. Clinicians can intercede with interventions to improve outcome in the mitigating secondary injury. The fundamental concepts in critical care management of moderate and severe TBI focus on alleviating intracranial pressure and avoiding hypotension and hypoxia. In addition to these important considerations, mechanical ventilation, appropriate transfusion of blood products, management of paroxysmal sympathetic hyperactivity, using nutrition as a therapy, and, of course, venous thromboembolism and seizure prevention are all essential in the management of moderate to severe TBI patients. These concepts will be reviewed using the recent 2016 Brain Trauma Foundation Guidelines to discuss best practices and identify future research priorities.

Hypertonic Solutions in Traumatic Brain Injury: A Systematic Review and Meta-Analysis

This study aims to evaluate the efficacy of hypertonic saline versus crystalloids (normal Saline/lactated Ringers) in improving clinical outcome in patients with traumatic brain injury (TBI). Electronic databases and grey literature (unpublished articles) were searched under different MeSH terms from 1990 to present. Randomized control trials, case–control studies and prospective cohort studies on decompressive craniectomy in TBI (>18-year-old). Clinical outcome measures included Glasgow Coma Outcome Scale (GCOS), Extended GCOS, and mortality. Data were extracted to Review Manager Software. A total of 115 articles that met the inclusion criteria were retrieved and analyzed. Ultimately, five studies were included in our meta-analysis, which revealed that patients with TBI who had hypertonic saline had no statistically significant likelihood of having a good outcome at discharge or 6 months than those who had crystalloid (odds ratio [OR]: 0.01; 95% confidence interval (CI): 0.03–0.05; P = 0.65). The relative risk (RR) of mortality in hypertonic saline versus the crystalloid at discharge or 6-month is RR: 0.80; 95% CI: 0.64–0.99; P = 0.04. The subgroup analysis showed that the group who had hypertonic solution significantly decreases the number of interventions versus the crystalloid group OR: 0.53; 95% CI: 0.48–0.59; P < 0.00001 and also reduces the length of intensive care unit stay (OR: 0.46; 95% CI: 0.21–1.01; P = 0.05). Hypertonic saline decreases the financial burden, but neither impacts the clinical outcome nor reduces the mortality. However, further clinical trials are required to prove if hypertonic saline has any role in improving the clinical and neurological status of patients with TBI versus the normal saline/lactated Ringers.

Hypertonic saline resuscitation protects against kidney injury induced by severe burns in rats

BACKGROUND

Proper fluid resuscitation can relieve visceral damage and improve survival in severely burned patients. This study compared the effectiveness of resuscitation with 400mEq/L hypertonic saline (HS) and sodium lactate Ringer's solution (LR) in rats with kidney injury caused by burn trauma.

METHODS

Rats (Sprague-Dawley) underwent burn injury and were randomized into sham, LR, and HS groups. Samples from the kidney were assayed for water content ratio, histopathology, and oxidative stress (superoxide dismutase (SOD) and malondialdehyde (MDA)). Serum sodium, renal function (creatinine and cystatin (Cys)-C), and inflammatory response (tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and high mobility group protein box (HMGB)-1) were also examined as serum markers.

RESULTS

Hypertonic saline resuscitation reduced the renal water content ratio and improved renal histopathology caused by severe burns. This effect was accompanied by reductions in serum creatinine and Cys-C as well as TNF-α, IL-1β, and HMGB1. Serum sodium concentration and SOD activity were increased, whereas MDA content was decreased in the kidney tissue of the HS group.

CONCLUSIONS

The data indicate that 400mEq/L HS solution reduces hyponatremia and renal edema, inhibits the release of inflammatory mediators, and alleviates oxidative stress injury, thus protecting against kidney injury induced by severe burns.

A Retrospective Study of Intracranial Pressure in Head-Injured Patients Undergoing Decompressive Craniectomy: A Comparison of Hypertonic Saline and Mannitol

Objective: The impact of hypertonic saline (HTS) on the control of increased intracranial pressure (ICP) in head-injured patients undergoing decompressive craniectomy (DC) has yet to be established. The current retrospective study was conducted to compare the effect of HTS and mannitol on lowering the ICP burden of these patients.

Methods: We reviewed data on patients who had sustained a traumatic brain injury (TBI) and were admitted to the First People's Hospital of Kunshan between January 1, 2012, and August 31, 2017. Patients who received only one type of hyperosmotic agent, 3% HTS or 20% mannitol, after DC were included. The daily ICP burden (h/day) and response to the hyperosmolar agent were used as primary outcome measures. The numbers of days in the intensive care unit and in the hospital, and the 2-weeks mortality rates were also compared between the groups.

Results: The 30 patients who received 3% HTS only and the 30 who received 20% mannitol only were identified for approximate matching and additional data analyses. The demographic characteristics of the patients in the two groups were comparable, but the daily ICP burden was significantly lower in the HTS group than in the mannitol group (0.89 ± 1.02 h/day vs. 2.11 ± 2.95 h/day, respectively; P = 0.038). The slope of the reduction in ICP in response to a bolus dose at baseline was higher with HTS than with mannitol (P = 0.001). However, the between-group difference in the 2-weeks mortality rates was not statistically significant (2 [HTS] vs. 1 [mannitol]; P = 0.554).

Conclusion: When used in equiosmolar doses, the reduction in the ICP of TBI patients achieved with 3% HTS was superior to that achieved with 20% mannitol after DC. However, this advantage did not seem to confer any additional benefit terms of short-term mortality.

Value of Ventricular Intracranial Pressure Monitoring for Traumatic Bifrontal Contusions

OBJECTIVE

To investigate clinical efficacy of and optimal therapeutic strategy for ventricular intracranial pressure monitoring (V-ICPM) in patients with traumatic bifrontal contusions (TBCs).

METHODS

From 8760 patients with traumatic brain injury treated between January 2010 and January 2016, a retrospective analysis was performed on 105 patients with TBCs who underwent V-ICPM and 282 patients with TBCs who did not. All patients underwent treatment at the 101st Hospital of PLA, Wuxi, China. Rates of successful conservative treatment, decompressive craniectomy, and bifrontal craniotomy; incidence of neurologic dysfunction; length of stay; and medical expenses were compared between groups.

RESULTS

Glasgow Outcome Scale was used to assess all patients during follow-up (range, 6 months to 5.5 years). There were no significant differences in prognosis between the 2 groups (P = 0.100). Compared with the patients who did not undergo V-ICPM, the V-ICPM group had a significantly better successful conservative treatment rate (64.8% vs. 47.2%, P = 0.002), decompressive craniectomy rate (8.1% vs. 22.1%, P = 0.008), and bifrontal craniotomy rate (5.7% vs. 15.6%, P = 0.01); shorter length of stay (P = 0.000); and lower medical expenses (P = 0.004).

CONCLUSIONS

Patients with TBCs should be strictly, closely, and dynamically observed by neurosurgery intensive care unit physicians and nurses. Patients should undergo ventricular intracranial pressure probe implantation in a timely manner. V-ICPM can help optimize treatment. Although V-ICPM did not significantly improve the prognosis of patients, it had many other advantages. V-ICPM warrants further clinical research and may be beneficial for patients with TBCs.

A Comparison of Pharmacologic Therapeutic Agents Used for the Reduction of Intracranial Pressure After Traumatic Brain Injury

OBJECTIVE

In neurotrauma care, a better understanding of treatments after traumatic brain injury (TBI) has led to a significant decrease in morbidity and mortality in this population. TBI represents a significant medical problem, and complications after TBI are associated with the initial injury and postevent intracranial processes such as increased intracranial pressure and brain edema. Consequently, appropriate therapeutic interventions are required to reduce brain tissue damage and improve cerebral perfusion. We present a contemporary review of literature on the use of pharmacologic therapies to reduce intracranial pressure after TBI and a comparison of their efficacy.

METHODS

This review was conducted by PubMed query. Only studies discussing pharmacologic management of patients after TBI were included. This review includes prospective and retrospective studies and includes randomized controlled trials as well as cohort, case-control, observational, and database studies. Systematic literature reviews, meta-analyses, and studies that considered conditions other than TBI or pediatric populations were not included.

RESULTS

Review of the literature describing the current pharmacologic treatment for intracranial hypertension after TBI most often discussed the use of hyperosmolar agents such as hypertonic saline and mannitol, sedatives such as fentanyl and propofol, benzodiazepines, and barbiturates. Hypertonic saline is associated with faster resolution of intracranial hypertension and restoration of optimal cerebral hemodynamics, although these advantages did not translate into long-term benefits in morbidity or mortality. In patients refractory to treatment with hyperosmolar therapy, induction of a barbiturate coma can reduce intracranial pressure, although requires close monitoring to prevent adverse events.

CONCLUSIONS

Current research suggests that the use of hypertonic saline after TBI is the best option for immediate decrease in intracranial pressure. A better understanding of the efficacy of each treatment option can help to direct treatment algorithms during the critical early hours of trauma care and continue to improve morbidity and mortality after TBI.

The Use of Mannitol and Hypertonic Saline Therapies in Patients with Elevated Intracranial Pressure: A Review of the Evidence

Patients with increased intracranial pressure generally require pharmacologic therapies and often more definitive treatments, such as surgical intervention. The overall goal of these interventions is to maintain or re-establish adequate cerebral blood flow and prevent herniation. Regardless of the cause of increased intracranial pressure, osmotherapy is considered the mainstay of medical therapy, and should be administered as soon as possible. This article reviews the history of hyperosmolar and hypertonic therapies, the Monro-Kellie hypothesis, and types of cerebral edema. Pharmacologic properties, clinical applications, complications, recommended monitoring during therapy, and risks versus benefits are also discussed.

Drug-Induced Acute Liver Failure

Drug-induced acute liver failure (ALF) disproportionately affects women and nonwhites. It is most frequently caused by antimicrobials and to a lesser extent by complementary and alternative medications, antiepileptics, antimetabolites, nonsteroidals, and statins. Most drug-induced liver injury ALF patients have hepatocellular injury pattern. Cerebral edema and intracranial hypertension are the most serious complications of ALF. Other complications include coagulopathy, sepsis, metabolic derangements, and renal, circulatory, and respiratory dysfunction. Although advances in intensive care have improved outcome, ALF has significant mortality without liver transplantation. Liver-assist devices may provide a bridge to transplant or to spontaneous recovery.

Traumatic Brain Injury: Bolus Versus Continuous Infusion of 3% Hypertonic Saline

Hypertonic saline (HTS) is used as an adjunct in the conservative management of increased intracranial pressure; however, the ideal concentration or route of delivery is unknown. Our objective was to assess whether there is a difference in route of delivery, bolus versus infusion, of 2% versus 3% HTS in patients with traumatic brain injury. The study comprises a retrospective analysis of all patients who sustained traumatic brain injury resulting in increased intracranial pressure that required HTS from January 2012 to December 2014. We examined time to therapeutic serum sodium concentration greater or equal to 150 mEq; incidence of ventriculostomy placement and neurosurgical intervention for refractory intracanial hypertension; and disability burden among the different infusates and route of delivery. A total of 169 patients received either 2% or 3% HTS, given as a bolus or continuous infusion. Patients had an average age of 61.4 years; 100 patients (59.2%) were male and 69 (40.8%) were female; 62 patients were taking either an antiplatelet or anticoagulant agent. Infusion of 3% saline was associated with the shortest interval to reaching a therapeutic level at 1.61 days (P = 0.024). There was no statistically significant difference between placement of a ventriculostomy among the bolus and infusion groups of 3% normal saline (NS) (P = 0.475). However, neurosurgical intervention was less prevalent in those receiving 3% infusion (P = 0.013). Infusion of 3% HTS was associated with a more rapid increase in serum sodium to therapeutic levels. Neurosurgical intervention for refractory hypertension was less prevalent in the 3% NS infusion group.

The effect of continuous hypertonic saline infusion and hypernatremia on mortality in patients with severe traumatic brain injury: a retrospective cohort study

PURPOSE

Hypertonic saline (HTS) is used to control intracranial pressure (ICP) in patients with traumatic brain injury (TBI); however, in prior studies, the resultant hypernatremia has been associated with increased mortality. We aimed to study the effect of HTS on ICP and mortality in patients with severe TBI.

METHODS

We performed a retrospective cohort study of 231 patients with severe TBI (Glasgow Coma Scale [GCS] ≤ 8) admitted to two neurotrauma units from 2006-2012. We recorded daily HTS, ICP, and serum sodium (Na) concentration. We used Cox proportional regression modelling for hospital mortality and incorporated the following time-dependent variables: use of HTS, hypernatremia, and desmopressin administration.

RESULTS

The mean [standard deviation (SD)] age of patients was 34 (17) and the median (interquartile range [IQR]) GCS was 6 [3-8]. Hypertonic saline was administered as a continuous infusion in 124 of 231 (54%) patients over 788 of 2,968 (27%) patient-days. Hypernatremia (Na > 145 mmol·L(-1)) developed in 151 of 231 (65%) patients over 717 of 2,968 (24%) patients-days. In patients who developed hypernatremia, the median [IQR] Na was 146 [142-147] mmol·L(-1). Overall hospital mortality was 26% (59 of 231 patients). After adjusting for baseline covariates, neither HTS (hazard ratio [HR], 1.07; 95% confidence interval [CI], 0.56 to 2.05; P = 0.84) nor hypernatremia (HR, 1.31; 95% CI, 0.68 to 2.55; P = 0.42) was associated with hospital mortality. There was no effect modification by either HTS or hypernatremia on each another. Patients who received HTS observed a significant decrease in ICP during their ICU stay compared with those who did not receive HTS (4 mmHg; 95% CI, 2 to 6; P < 0.001 vs 2 mmHg; 95% CI, -1 to 5; P = 0.14).

CONCLUSIONS

Hypertonic saline and hypernatremia are not associated with hospital mortality in patients with severe TBI.

Comparison of equiosmolar concentrations of hypertonic saline and mannitol for intraoperative lax brain in patients undergoing craniotomy

Background:

Osmotherapy is the frequently used for the treatment of intracranial pressure. The purpose of the study was to compare the effect of equiosmolar solution of 3% hypertonic saline and 20% mannitol on brain relaxation in supratentorial tumor surgery.

Methods:

After institutional review board approval and written informed consent, 50 patients aged >18, Glasgow Coma Scale (GCS) >13 with ASA physical status 1, 2, and 3 scheduled to undergo craniotomy for supratentorial tumors were enrolled in this prospective, randomized study. Patients received 5 ml/kg of either 3% hypertonic saline (n = 25) or 20% mannitol (n = 25). Hemodynamic variables (heart rate [HR], SBP, DBP, MBP, and central venous pressure [CVP]), serum electrolytes, serum osmolality, urine output, and fluid balance were measured. The surgeon assessed the brain condition on four point scale (1 = perfectly relaxed, 2 = satisfactorily relaxed, 3 = firm brain, and 4 = bulging brain), who was blinded to study drug.

Results:

Brain relaxation was comparable in two groups and there was no significant difference (P = 0.633). The number of brain conditions classified as perfectly relaxed, satisfactorily relaxed, firm brain, and bulging brain in the HS group was 8, 13, 3, and 1, respectively, whereas it was 5, 17, 3, and 0, respectively, in the M group. There was no significant difference in hemodynamic variables between the two groups except CVP at 30 min (P = 048). Compared with mannitol, hypertonic saline caused increase in the serum osmolality at 120 min (P = 0.008) and in serum sodium at 120 min (P = 0.001). Urine output was higher with mannitol than hypertonic saline (P = 0.001).

Conclusion:

3% hypertonic saline and 20% mannitol are equally effective for brain relaxation in elective supratentorial tumor surgery and compared with mannitol, hypertonic saline was associated with less diuretic effect.

Hypertonic saline for the management of raised intracranial pressure after severe traumatic brain injury

Hyperosmolar agents are commonly used as an initial treatment for the management of raised intracranial pressure (ICP) after severe traumatic brain injury (TBI). They have an excellent adverse-effect profile compared to other therapies, such as hyperventilation and barbiturates, which carry the risk of reducing cerebral perfusion. The hyperosmolar agent mannitol has been used for several decades to reduce raised ICP, and there is accumulating evidence from pilot studies suggesting beneficial effects of hypertonic saline (HTS) for similar purposes. An ideal therapeutic agent for ICP reduction should reduce ICP while maintaining cerebral perfusion (pressure). While mannitol can cause dehydration over time, HTS helps maintain normovolemia and cerebral perfusion, a finding that has led to a large amount of pilot data being published on the benefits of HTS, albeit in small cohorts. Prophylactic therapy is not recommended with mannitol, although it may be beneficial with HTS. To date, no large clinical trial has been performed to directly compare the two agents. The best current evidence suggests that mannitol is effective in reducing ICP in the management of traumatic intracranial hypertension and carries mortality benefit compared to barbiturates. Current evidence regarding the use of HTS in severe TBI is limited to smaller studies, which illustrate a benefit in ICP reduction and perhaps mortality.

Hypertonic saline reduces cumulative and daily intracranial pressure burdens after severe traumatic brain injury

OBJECT

Increased intracranial pressure (ICP) in patients with traumatic brain injury (TBI) is associated with a higher mortality rate and poor outcome. Mannitol and hypertonic saline (HTS) have both been used to treat high ICP, but it is unclear which one is more effective. Here, the authors compare the effect of mannitol versus HTS on lowering the cumulative and daily ICP burdens after severe TBI.

METHODS

The Brain Trauma Foundation TBI-trac New York State database was used for this retrospective study. Patients with severe TBI and intracranial hypertension who received only 1 type of hyperosmotic agent, mannitol or HTS, were included. Patients in the 2 groups were individually matched for Glasgow Coma Scale score (GCS), pupillary reactivity, craniotomy, occurrence of hypotension on Day 1, and the day of ICP monitor insertion. Patients with missing or erroneous data were excluded. Cumulative and daily ICP burdens were used as primary outcome measures. The cumulative ICP burden was defined as the total number of days with an ICP of > 25 mm Hg, expressed as a percentage of the total number of days of ICP monitoring. The daily ICP burden was calculated as the mean daily duration of an ICP of > 25 mm Hg, expressed as the number of hours per day. The numbers of intensive care unit (ICU) days, numbers of days with ICP monitoring, and 2-week mortality rates were also compared between the groups. A 2-sample t-test or chi-square test was used to compare independent samples. The Wilcoxon signed-rank or Cochran-Mantel-Haenszel test was used for comparing matched samples.

RESULTS

A total of 35 patients who received only HTS and 477 who received only mannitol after severe TBI were identified. Eight patients in the HTS group were excluded because of erroneous or missing data, and 2 other patients did not have matches in the mannitol group. The remaining 25 patients were matched 1:1. Twenty-four patients received 3% HTS, and 1 received 23.4% HTS as bolus therapy. All 25 patients in the mannitol group received 20% mannitol. The mean cumulative ICP burden (15.52% [HTS] vs 36.5% [mannitol]; p = 0.003) and the mean (± SD) daily ICP burden (0.3 ± 0.6 hours/day [HTS] vs 1.3 ± 1.3 hours/day [mannitol]; p = 0.001) were significantly lower in the HTS group. The mean (± SD) number of ICU days was significantly lower in the HTS group than in the mannitol group (8.5 ± 2.1 vs 9.8 ± 0.6, respectively; p = 0.004), whereas there was no difference in the numbers of days of ICP monitoring (p = 0.09). There were no significant differences between the cumulative median doses of HTS and mannitol (p = 0.19). The 2-week mortality rate was lower in the HTS group, but the difference was not statistically significant (p = 0.56).

CONCLUSIONS

HTS given as bolus therapy was more effective than mannitol in lowering the cumulative and daily ICP burdens after severe TBI. Patients in the HTS group had significantly lower number of ICU days. The 2-week mortality rates were not statistically different between the 2 groups.

Post-traumatic multimodal brain monitoring: response to hypertonic saline

Emerging evidence suggests that hypertonic saline (HTS) is efficient in decreasing intracranial pressure (ICP). However there is no consensus about its interaction with brain hemodynamics and oxygenation. In this study, we investigated brain response to HTS bolus with multimodal monitoring after severe traumatic brain injury (TBI). We included 18 consecutive TBI patients during 10 days after neurocritical care unit admission. Continuous brain monitoring applied included ICP, tissue oxygenation (PtO2) and cerebral blood flow (CBF). Cerebral perfusion pressure (CPP), cerebrovascular resistance (CVR), and reactivity indices related to pressure (PRx) and flow (CBFx) were calculated. ICM+software was used to collect and analyze monitoring data. Eleven of 18 (61%) patients developed 99 episodes of intracranial hypertension (IHT) greater than 20 mm Hg that were managed with 20% HTS bolus. Analysis over time was performed with linear mixed-effects regression modelling. After HTS bolus, ICP and CPP improved over time (p<0.001) following a quadratic model. From baseline to 120 min, ICP had a mean decrease of 6.2 mm Hg and CPP a mean increase of 3.1 mmHg. Mean increase in CBF was 7.8 mL/min/100 g (p<0.001) and mean decrease in CVR reached 0.4 mm Hg*min*100 g/mL (p=0.01). Both changes preceded pressures improvement. PtO2 exhibited a marginal increase and no significant models for time behaviour could be fitted. PRx and CBFx were best described by a linear decreasing model showing autoregulation recover after HTS (p=0.01 and p=0.04 respectively). During evaluation, CO2 remained constant and sodium level did not exhibit significant variation. In conclusion, management of IHT with 20% HTS significantly improves cerebral hemodynamics and cerebrovascular reactivity with recovery of CBF appearing before rise in CPP and decrease in ICP. In spite of cerebral hemodynamic improvement, no significant changes in brain oxygenation were identified.

Variable change in renal function by hypertonic saline

AIM: To investigate the effects of hypertonic saline in the neurocritical care population.

METHODS: We retrospectively reviewed our hospital’s use of hypertonic saline (HS) since March of 2005, and prospectively since October 2010. Comparisons were made between admission diagnoses, creatinine change (Cr), and HS formulation (3% NaCl, 3% NaCl/sodium acetate mix, and 23.4% NaCl) to patients receiving normal saline or lactated ringers. The patients (n = 1329) of the retrospective portion were identified. The data presented represents the first 230 patients with data.

RESULTS: Significant differences in Acute Physiology and Chronic Health Evaluation II scores and Glasgow Coma Scale scores occurred between different saline formulations. No significant correlation of Cl^- or Na⁺ with Cr, nor with saline types, occurred. When dichotomized by diagnosis, significant correlations appear. Traumatic brain injury (TBI) patients demonstrated moderate correlation between Na⁺ and Cr of 0.45. Stroke patients demonstrated weak correlations between Na⁺ and Cr, and Cl^- and Cr (0.19 for both). Patients receiving HS and not diagnosed with intracerebral hemorrhage, stroke, subarachnoid hemorrhage, or TBI demonstrated a weak but significant correlation between Cl^- and Cr at 0.29.

CONCLUSION: Cr directly correlates with Na⁺ or Cl^- in stroke, Na⁺ in TBI, and Cl^- in other populations. Prospective comparison of HS and renal function is needed.

Effective treatment of refractory intracranial hypertension after traumatic brain injury with repeated boluses of 14.6% hypertonic saline

Object

Normal intracranial pressure (ICP) and cerebral perfusion pressure (CPP) have been identified as favorable prognostic factors in the outcome of patients with traumatic brain injuries (TBIs). Osmotic diuretics and hypertonic saline (HTS) are commonly used to treat elevated ICP in patients with TBI; however, sustained effects of repeated high-concentration HTS boluses for severely refractory ICP elevation have not been studied. The authors' goal in this study was to determine whether repeated 14.6% HTS boluses were efficacious in treating severely refractory intracranial hypertension in patients with TBI.

Methods

In a prospective cohort study in a neurocritical care unit, adult TBI patients with sustained ICP > 30 mm Hg for more than 30 minutes after exhaustive medical and/or surgical therapy received repeated 15-minute boluses of 14.6% HTS over 12 hours through central venous access.

Results

Response to treatment was evaluated in 11 patients. Within 5 minutes of bolus administration, mean ICP decreased from 40 to 33 mm Hg (30% reduction, p < 0.05). Intracranial pressure–lowering effects were sustained for 12 hours (41% reduction, p < 0.05) with multiple boluses (mean number of boluses 7 ± 5.5). The mean CPP increased 22% and 32% from baseline at 15 and 30 minutes, respectively (p < 0.05). The mean serum sodium level (SNa) at baseline was 155 ± 7.1 mEq/L, and after multiple boluses of 14.6% HTS, SNa at 12 hours was 154 ± 7.1 mEq/L. The mean heart rate, systolic blood pressure, blood urea nitrogen, and creatinine demonstrated no significant change throughout the study.

Conclusions

The subset of TBI patients with intracranial hypertension that is completely refractory to all other medical therapies can be treated effectively and safely with repeated boluses of 14.6% HTS rather than a one-time dose.

Hypertonic saline in elevated intracranial pressure: past, present, and future

Hypertonic Saline (HS) has been a proven and effective therapy and a safe alternative to mannitol in patients with increase intracranial pressure (ICP). We hereby present a case of 25-year-old women with intracranial bleed secondary to right parietal arteriovenous malformation. Patient underwent surgery for evacuation of hematoma and resection of arteriovenous malformation. Post- operative course was complicated by recurrent episodes of elevated ICP. She received total of 17 doses of 23.4% HS and 30 doses of mannitol with good outcome. Despite reluctance from some clinicians to use HS, hypertonic saline seems to be a safe and effective therapy.

Management of intracerebral pressure in the neurosciences critical care unit

Management of intracranial pressure in neurocritical care remains a potentially valuable target for improvements in therapy and patient outcomes. Surrogate markers of increased intracranial pressure, invasive monitors, and standard therapy, as well as promising new approaches to improve cerebral compliance are discussed, and a current review of the literature addressing this metric in neuroscience critical care is provided.

Traumatic brain injury: pathophysiology, monitoring, and mechanism-based care

Traumatic brain injury, which may be blunt or penetrating, begins altering intracranial physiology at the moment of impact as primary brain trauma. This article differentiates blunt versus penetrating brain trauma, primary versus secondary brain injury, and subsequent intracranial pathophysiology. Discussion and case study correlate intracranial pathophysiology and multisystem influences on evolving brain injury with mechanism-based interventions to modulate brain components (brain, blood, and cerebrospinal fluid volumes). The discussion also explores the effects of controlled ventilation, cardiopulmonary physiology, and global physiologic state on secondary injury, control of intracranial pressure, and recovery.