Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury

Efficacy of Intravenous 20% Mannitol vs 3% Hypertonic Saline in Reducing Intracranial Pressure in Nontraumatic Brain Injury: A Systematic Review and Meta-analysis

Background

Nontraumatic brain injury encompasses various pathological processes and medical conditions that result in brain dysfunction and neurological impairment without direct physical trauma. The study aimed to assess the efficacy of intravenous administration of 20% mannitol and 3% hypertonic saline to reduce intracranial pressure in nontraumatic brain injury.

Materials and methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed for study selection and data extraction. The search was conducted in the PubMed, Embase, and Scopus databases, including articles published in English from January 2003 to December 2023. Our study included randomized controlled trials, comparative studies, prospective analyses, and retrospective cohort studies. We extracted data on baseline characteristics of patients, intervention details, major outcomes, and complications. Quality assessment was performed using the Jadad scale and the Robvis assessment tool for risk of bias.

Results

A total of 14 studies involving 1,536 patients were included in the analysis. Seven studies reported hypertonic saline as more effective in reducing intracranial pressure, while three studies found similar effectiveness for both interventions. Adverse events were reported in only three studies. The studies that reported complication rates ranged from 21 to 79%. A meta-analysis was conducted on five studies, showing varying rates of adverse events associated with mannitol and hypertonic saline.

Conclusion

Both hypertonic saline solution and mannitol have been explored as treatment options for decreasing intracranial pressure in nontraumatic brain injuries. While some studies indicate the superiority of hypertonic saline, others report similar effectiveness between the two interventions.

How to cite this article

Choudhury A, Ravikant, Bairwa M, Jithesh G, Kumar S, Kumar N. Efficacy of Intravenous 20% Mannitol vs 3% Hypertonic Saline in Reducing Intracranial Pressure in Nontraumatic Brain Injury: A Systematic Review and Meta-analysis. Indian J Crit Care Med 2024;28(7):686-695.

Hypertonic Saline Versus Other Intracranial-Pressure-Lowering Agents for Patients with Acute Traumatic Brain Injury: A Systematic Review and Meta-analysis

Acute traumatic brain injury (TBI) is a major cause of mortality and disability worldwide. Intracranial pressure (ICP)-lowering is a critical management priority in patients with moderate to severe acute TBI. We aimed to evaluate the clinical efficacy and safety of hypertonic saline (HTS) versus other ICP-lowering agents in patients with TBI. We conducted a systematic search from 2000 onward for randomized controlled trials (RCTs) comparing HTS vs. other ICP-lowering agents in patients with TBI of all ages. The primary outcome was the Glasgow Outcome Scale (GOS) score at 6 months (PROSPERO CRD42022324370). Ten RCTs (760 patients) were included. Six RCTs were included in the quantitative analysis. There was no evidence of an effect of HTS on the GOS score (favorable vs. unfavorable) compared with other agents (risk ratio [RR] 0.82, 95% confidence interval [CI] 0.48-1.40; n = 406; 2 RCTs). There was no evidence of an effect of HTS on all-cause mortality (RR 0.96, 95% CI 0.60-1.55; n = 486; 5 RCTs) or total length of stay (RR 2.36, 95% CI - 0.53 to 5.25; n = 89; 3 RCTs). HTS was associated with adverse hypernatremia compared with other agents (RR 2.13, 95% CI 1.09-4.17; n = 386; 2 RCTs). The point estimate favored a reduction in uncontrolled ICP with HTS, but this was not statistically significant (RR 0.52, 95% CI 0.26-1.04; n = 423; 3 RCTs). Most included RCTs were at unclear or high risk of bias because of lack of blinding, incomplete outcome data, and selective reporting. We found no evidence of an effect of HTS on clinically important outcomes and that HTS is associated with adverse hypernatremia. The included evidence was of low to very low certainty, but ongoing RCTs may help to the reduce this uncertainty. In addition, heterogeneity in GOS score reporting reflects the need for a standardized TBI core outcome set.

Evidence-based management of adult traumatic brain injury with raised intracranial pressure in intensive critical care unit at resource-limited settings: a literature review

Background

In underdeveloped countries, there is a greater incidence of mortality and morbidity arising from trauma, with traumatic brain injury (TBI) accounting for 50% of all trauma-related deaths. The occurrence of elevated intracranial pressure (ICP), which is a common pathophysiological phenomenon in cases of TBI, acts as a contributing factor to unfavorable outcomes. The aim of this systematic review is to analyze the existing literature regarding the management of adult TBI with raised ICP in an intensive critical care unit, despite limited resources.

Methods

This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis protocol. Search engines such as PubMed, the Cochrane database, and Google Scholar were utilized to locate high-level evidence that would facilitate the formation of sound conclusions.

Result

A total of 11 715 articles were identified and individually assessed to determine their eligibility for inclusion or exclusion based on predetermined criteria and outcome variables. The methodological quality of each study was evaluated using recommended criteria. Ultimately, the review consisted of 51 articles.

Conclusion

Physical examination results and noninvasive assessments of the optic nerve sheath diameter (ONSD) via sonography are positively associated with elevated ICP, and are employed as diagnostic and monitoring tools for elevated ICP in resource-limited settings. Management of elevated ICP necessitates an algorithmic approach that utilizes prophylactic measures and acute intervention treatments to mitigate the risk of secondary brain injury.

Intracranial Pressure Monitoring and Treatment Thresholds in Acute Neural Injury: A Narrative Review of the Historical Achievements, Current State, and Future Perspectives

Since its introduction in the 1960s, intracranial pressure (ICP) monitoring has become an indispensable tool in neurocritical care practice and a key component of the management of moderate/severe traumatic brain injury (TBI). The primary utility of ICP monitoring is to guide therapeutic interventions aimed at maintaining physiological ICP and preventing intracranial hypertension. The rationale for such ICP maintenance is to prevent secondary brain injury arising from brain herniation and inadequate cerebral blood flow. There exists a large body of evidence indicating that elevated ICP is associated with mortality and that aggressive ICP control protocols improve outcomes in severe TBI patients. Therefore, current management guidelines recommend a cerebral perfusion pressure (CPP) target range of 60-70 mm Hg and an ICP threshold of >20 or >22 mm Hg, beyond which therapeutic intervention should be initiated. Though our ability to achieve these thresholds has drastically improved over the past decades, there has been little to no change in the mortality and morbidity associated with moderate-severe TBI. This is a result of the "one treatment fits all" dogma of current guideline-based care that fails to take individual phenotype into account. The way forward in moderate-severe TBI care is through the development of continuously derived individualized ICP thresholds. This narrative review covers the topic of ICP monitoring in TBI care, including historical context/achievements, current monitoring technologies and indications, treatment methods, associations with patient outcome and multi-modal cerebral physiology, present controversies surrounding treatment thresholds, and future perspectives on personalized approaches to ICP-directed therapy.

Risk of recurrence and pregnancy outcomes in young women with breast cancer who do and do not undergo fertility preservation

PURPOSE

To assess the impact of fertility preservation (FP) requiring ovarian stimulation on breast cancer outcomes and pregnancy after breast cancer.

METHODS

Women aged ≤ 40 years diagnosed with stage I-III breast cancer between 2007 and 2018 and referred for FP consultation prior to systemic therapy were identified from a British Columbia fertility center database. The primary endpoint was invasive breast cancer-free survival (iBCFS) and secondary endpoints were overall survival (OS) and achievement of pregnancy. Survival and pregnancy endpoints were compared using Cox and logistic regression analyses, respectively, for patients who did and did not undergo FP.

RESULTS

The study included 153 patients, with 71 (46%) in the FP group and 82 (54%) in the non-FP group. Patients who underwent FP were more likely to be ECOG 0 (99% vs. 88%, p = 0.011) and receive chemotherapy (93% vs. 67%, p < 0.001), but had similar ER positivity status to non-FP patients (70% vs. 79%, p = 0.21). Over a median follow-up of 4.1 years, there were no differences in iBCFS (HR 1.006, 95% CI 0.416-2.438, p = 0.988) or OS (HR 0.789, 95% CI 0.210-2.956, p = 0.725) between FP and non-FP groups. Patients who underwent FP had higher odds of conceiving at least once (OR 3.024, 95% CI 1.312-6.970, p = 0.008).

CONCLUSION

At a median follow-up of 4.1 years, FP did not impact iBCFS or OS, supporting its safety in young women with breast cancer. In addition, patients who underwent FP were more likely to become pregnant after breast cancer, highlighting the value of pre-oncologic treatment FP in survivorship family planning.

Targeting Nrf2-Mediated Oxidative Stress Response in Traumatic Brain Injury: Therapeutic Perspectives of Phytochemicals

Traumatic brain injury (TBI), known as mechanical damage to the brain, impairs the normal function of the brain seriously. Its clinical symptoms manifest as behavioral impairment, cognitive decline, communication difficulties, etc. The pathophysiological mechanisms of TBI are complex and involve inflammatory response, oxidative stress, mitochondrial dysfunction, blood-brain barrier (BBB) disruption, and so on. Among them, oxidative stress, one of the important mechanisms, occurs at the beginning and accompanies the whole process of TBI. Most importantly, excessive oxidative stress causes BBB disruption and brings injury to lipids, proteins, and DNA, leading to the generation of lipid peroxidation, damage of nuclear and mitochondrial DNA, neuronal apoptosis, and neuroinflammatory response. Transcription factor NF-E2 related factor 2 (Nrf2), a basic leucine zipper protein, plays an important role in the regulation of antioxidant proteins, such as oxygenase-1(HO-1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), and glutathione peroxidase (GPx), to protect against oxidative stress, neuroinflammation, and neuronal apoptosis. Recently, emerging evidence indicated the knockout (KO) of Nrf2 aggravates the pathology of TBI, while the treatment of Nrf2 activators inhibits neuronal apoptosis and neuroinflammatory responses via reducing oxidative damage. Phytochemicals from fruits, vegetables, grains, and other medical herbs have been demonstrated to activate the Nrf2 signaling pathway and exert neuroprotective effects in TBI. In this review, we emphasized the contributive role of oxidative stress in the pathology of TBI and the protective mechanism of the Nrf2-mediated oxidative stress response for the treatment of TBI. In addition, we summarized the research advances of phytochemicals, including polyphenols, terpenoids, natural pigments, and otherwise, in the activation of Nrf2 signaling and their potential therapies for TBI. Although there is still limited clinical application evidence for these natural Nrf2 activators, we believe that the combinational use of phytochemicals such as Nrf2 activators with gene and stem cell therapy will be a promising therapeutic strategy for TBI in the future.

Improved Pressure Equalization Ratio Following Mannitol Administration in Patients With Severe TBI: A Preliminary Study of a Potential Bedside Marker for Response to Therapy

BACKGROUND

Performing a cerebrospinal fluid (CSF) drainage challenge can be used to measure the pressure equalization (PE) ratio, which describes the extent to which CSF drainage can equalize pressure to the height of the external ventricular drain and may serve as a correlate of cerebral edema. We sought to assess whether treatment with mannitol improves PE ratio in patients with severe traumatic brain injury (TBI) with elevated intracranial pressure (ICP).

METHODS

We studied consecutive patients with TBI and brain edema on computed tomography scan and an external ventricular drain (EVD), admitted to the neurointensive care unit. PE ratio, defined as ICP prior to CSF drainage minus ICP after CSF drainage divided by ICP prior to CSF drainage minus EVD height, was measured as previously described. Patients were treated with mannitol for raised ICP based on clinical indication and PE ratio measured before and after mannitol administration.

RESULTS

We studied 20 patients with severe TBI with raised ICP. Mean ICP prior to mannitol treatment was 29 ± 7 mm Hg. PE ratio rose substantially after mannitol treatment (0.62 ± 0.24 vs. 0.29 ± 0.20, p < 0.0001), indicating an improved ability to drain CSF and equalize ICP with the preset height of the EVD. The combination of mannitol and CSF drainage led to an improved reduction in ICP compared with that seen before mannitol therapy (11 ± 2 mm Hg vs. 6 ± 2 mm Hg, p < 0.01), and led to a decrease in ICP below the 20 mm Hg threshold in 77% of cases.

CONCLUSIONS

Treatment with mannitol leads to a substantial improvement in PE ratio that reflects the ability to achieve a greater decrease in ICP when CSF drainage is performed after mannitol administration. This preliminary study raises the possibility that PE ratio may be useful to follow response to therapy in patients with cerebral edema and raised ICP. Further studies to determine whether PE ratio may serve as an easily obtained and clinically useful surrogate marker for the extent of brain edema are warranted.

Downregulation of microRNA-9-5p promotes synaptic remodeling in the chronic phase after traumatic brain injury

The level of microRNA-9-5p (miRNA-9-5p) in brain tissues is significantly changed in the chronic phase after traumatic brain injury (TBI). However, the effect of miRNA-9-5p on brain function after TBI has not been elucidated. In this study, we used a controlled cortical impact (CCI) model to induce TBI in Sprague-Dawley rats. Brain microvascular endothelial cells (BMECs), astrocytes, and neurons were extracted from immature Sprague-Dawley rats and cocultured to reconstruct the neurovascular unit (NVU) in vitro. The results showed that downregulation of miRNA-9-5p in the chronic phase contributed to neurological function recovery by promoting astrocyte proliferation and increasing the release of astrocyte-derived neurotrophic factors around injured brain tissues after TBI. A dual-luciferase reporter assay validated that miRNA-9-5p was a post-transcriptional modulator of thrombospondin 2 (Thbs-2), and downregulation of miRNA-9-5p promoted Thbs-2 expression in astrocytes. Furthermore, we verified that Thbs-2 can promote Notch pathway activation by directly binding to Jagged and Notch. Through in vitro experiments, we found that the expression of synaptic proteins and the number of synaptic bodies were increased in neurons in the NVU, which was constructed using astrocytes pretreated with miRNA-9-5p inhibitor. Moreover, we also found that downregulation of miRNA-9-5p promoted Thbs-2 expression in astrocytes, which activated the Notch/cylindromatosis/transforming growth factor-β-activated kinase 1 pathway in neurons and promoted the expression of synaptic proteins, including post-synaptic density protein 95 and synaptotagmin. Based on these results, miRNA-9-5p may be a new promising prognostic marker and treatment target for TBI.

Transscleral cyclophotocoagulation with MicroPulse® laser versus Ahmed valve implantation in patients with advanced primary open-angle glaucoma

PURPOSE

To compare the efficacy of transscleral cyclophotocoagulation with MicroPulse^® laser (Iridex, Silicon Valley, California, USA) with 3000 mW to Ahmed valve implantation in eyes with advanced stage of primary open-angle glaucoma.

METHODS

In a prospective observational clinical study, 30 patients (30 eyes) with advanced open-angle glaucoma were randomized for either micropulse transscleral cyclophotocoagulation with 3000 mW or Ahmed valve implantation. Fifteen eyes were treated with transscleral cyclophotocoagulation with MicroPulse^® laser with 3000 mW (group A) and 15 eyes with Ahmed valve implantation (group B). As inclusion criteria are included the diagnosis of advanced primary open-angle glaucoma, an intraocular pressure above 21 mmHg, cup-to-disk ratio 0.9-1.0, failure to meet the target IOP with either maximal tolerated local medical therapy (2-4 antiglaucoma agents) or systemic therapy (acetazolamide). The follow-up time of the study was 12 months. An absolute success was defined the achievement of IOP between 6 and 15 mmHg and at least 30% reduction of the IOP from baseline under reduced or the same number of antiglaucoma agents after the surgical procedure without following glaucoma surgeries and as qualified success the achievement of IOP between 6 and 18 mmHg and at least 20% reduction of the IOP from baseline regardless of the number of postoperative antiglaucoma agents. The efficacy was evaluated by estimating the absolute success rate and the qualified success rate using the Kaplan-Meier survival analysis.

RESULTS

A reduction of the intraocular pressure > 30% was achieved in 33.3% of group A and in 73.3% of group B during the follow-up period of 12 months. A statistically significant decrease in the number of eye drops was observed in both groups (p < 0.01). 53.3% of the eyes of group A underwent additional anti-glaucoma procedures to achieve target intraocular pressure. The number of the local medications that were administered 12 months after the ocular surgery was 2 (± 1.3) in group A and 0.57 (± 0.9) in group B, compared to 3.2 (± 0.78) in group A and 3.33 (± 0.7) in group B administered prior to the surgery (p: 0.016). 8 eyes (53.33%) in group A were referred for additional treatment due to an acute postoperative rise in IOP (5 eyes: mTS-CPC, 1 eye: canaloplasty, 2 eyes: AGV implantation). No further anti-glaucoma procedures were necessary in group B.

CONCLUSION

The Ahmed valve implantation achieves a more efficient decrease of the intraocular pressure as well as of the number of antiglaucoma agents than the transscleral cyclophotocoagulation with MicroPulse^® diode laser 3000 mW. Additionally, the Ahmed valve implantation showed better results in terms of absolute and qualified success rates in the treatment of advanced primary open-angle glaucoma.

Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury

BACKGROUND

Increased intracranial pressure has been shown to be strongly associated with poor neurological outcomes and mortality for patients with acute traumatic brain injury. Currently, most efforts to treat these injuries focus on controlling the intracranial pressure. Hypertonic saline is a hyperosmolar therapy that is used in traumatic brain injury to reduce intracranial pressure. The effectiveness of hypertonic saline compared with other intracranial pressure-lowering agents in the management of acute traumatic brain injury is still debated, both in the short and the long term.

OBJECTIVES

To assess the comparative efficacy and safety of hypertonic saline versus other intracranial pressure-lowering agents in the management of acute traumatic brain injury.

SEARCH METHODS

We searched Cochrane Injuries' Specialised Register, CENTRAL, PubMed, Embase Classic+Embase, ISI Web of Science: Science Citation Index and Conference Proceedings Citation Index-Science, as well as trials registers, on 11 December 2019. We supplemented these searches with searches of four major Chinese databases on 19 September 2018. We also checked bibliographies, and contacted trial authors to identify additional trials.

SELECTION CRITERIA

We sought to identify all randomised controlled trials (RCTs) of hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury of any severity. We excluded cross-over trials as incompatible with assessing long-term outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results to identify potentially eligible trials and extracted data using a standard data extraction form. Outcome measures included: mortality at end of follow-up (all-cause); death or disability (as measured by the Glasgow Outcome Scale (GOS)); uncontrolled intracranial pressure (defined as failure to decrease the intracranial pressure to target and/or requiring additional intervention); and adverse events e.g. rebound phenomena; pulmonary oedema; acute renal failure during treatment).

MAIN RESULTS

Six trials, involving data from 287 people, met the inclusion criteria. The majority of participants (91%) had a diagnosis of severe traumatic brain injury. We had concerns about particular domains of risk of bias in each trial, as physicians were not reliably blinded to allocation, two trials contained participants with conditions other than traumatic brain injury and in one trial, we had concerns about missing data for important outcomes. The original protocol was available for only one trial and other trials (where registered) were registered retrospectively. Meta-analysis for both the primary outcome (mortality at final follow-up) and for 'poor outcome' as per conventionally dichotomised GOS criteria, was only possible for two trials. Synthesis of long-term outcomes was inhibited by the fact that two trials ceased data collection within two hours of a single bolus dose of an intracranial pressure-lowering agent and one at discharge from the intensive care unit (ICU). Only three trials collected data after participants were released from hospital, one of which did not report mortality and reported a 'poor outcome' by GOS criteria in an unconventional way. Substantial missing data in a key trial meant that in meta-analysis we report 'best-case' and 'worst-case' estimates alongside available case analysis. In no scenario did we discern a clear difference between treatments for either mortality or poor neurological outcome. Due to variation in modes of drug administration (including whether it followed or did not follow cerebrospinal fluid (CSF) drainage, as well as different follow-up times and ways of reporting changes in intracranial pressure, as well as no uniform definition of 'uncontrolled intracranial pressure', we did not perform meta-analysis for this outcome and report results narratively, by individual trial. Trials tended to report both treatments to be effective in reducing elevated intracranial pressure but that hypertonic saline had increased benefits, usually adding that pretreatment factors need to be considered (e.g. serum sodium and both system and brain haemodynamics). No trial provided data for our other outcomes of interest. We consider evidence quality for all outcomes to be very low, as assessed by GRADE; we downgraded all conclusions due to imprecision (small sample size), indirectness (due to choice of measurement and/or selection of participants without traumatic brain injury), and in some cases, risk of bias and inconsistency. Only one of the included trials reported data on adverse effects; a rebound phenomenon, which was present only in the comparator group (mannitol). None of the trials reported data on pulmonary oedema or acute renal failure during treatment. On the whole, trial authors do not seem to have rigorously sought to collect data on adverse events.

AUTHORS' CONCLUSIONS

This review set out to find trials comparing hypertonic saline to a potential range of other intracranial pressure-lowering agents, but only identified trials comparing it with mannitol or mannitol in combination with glycerol. Based on limited data, there is weak evidence to suggest that hypertonic saline is no better than mannitol in efficacy and safety in the long-term management of acute traumatic brain injury. Future research should be comprised of large, multi-site trials, prospectively registered, reported in accordance with current best practice. Trials should investigate issues such as the type of traumatic brain injury suffered by participants and concentration of infusion and length of time over which the infusion is given.

Hypertonic saline versus other intracranial pressure-lowering agents for people with acute traumatic brain injury

BACKGROUND

Increased intracranial pressure (ICP) has been shown to be strongly associated with poor neurological outcomes and mortality for patients with acute traumatic brain injury (TBI). Currently, most efforts to treat these injuries focus on controlling the ICP. Hypertonic saline (HTS) is a hyperosmolar therapy that is used in traumatic brain injury to reduce intracranial pressure. The effectiveness of HTS compared with other ICP-lowering agents in the management of acute TBI is still debated, both in the short and the long term.

OBJECTIVES

To assess the comparative efficacy and safety of hypertonic saline versus other ICP-lowering agents in the management of acute TBI.

SEARCH METHODS

We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library, PubMed, Embase Classic+Embase (OvidSP), ISI Web of Science: Science Citation Index and Conference Proceedings Citation Index-Science, as well as trials registers, on 11 December 2019. We supplemented these searches using four major Chinese databases on 19 September 2018. We also checked bibliographies, and contacted study authors to identify additional studies.

SELECTION CRITERIA

We sought to identify all randomised controlled trials (RCTs) of HTS versus other intracranial pressure-lowering agents for people with acute TBI of any severity. We excluded cross-over trials as incompatible with assessing long term outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results to identify potentially eligible trials and extracted data using a standard data extraction form. Outcome measures included: mortality at end of follow-up (all-cause); death or disability (as measured by the Glasgow Outcome Scale (GOS)); uncontrolled ICP (defined as failure to decrease the ICP to target and/or requiring additional intervention); and adverse events (AEs) (e.g. rebound phenomena; pulmonary oedema; acute renal failure during treatment).

MAIN RESULTS

Six trials, involving data from 295 people, met the inclusion criteria. The majority of participants (89%) had a diagnosis of severe TBI. We had concerns about particular domains of risk of bias in each trial, as physicians were not reliably blinded to allocation, two trials contained participants with conditions other than TBI and in one trial, there were concerns about missing data for important outcomes. The original protocol was available for only one study and other trials (where registered) were registered retrospectively. Meta-analysis for both the primary outcome (mortality at final follow up) and for 'poor outcome' as per conventionally dichotomised GOS criteria, was only possible for two studies. Synthesis of long-term outcomes was inhibited by the fact that two ceased data collection within two hours of a single bolus dose of an ICP-lowering agent and one at discharge from ICU. Only three studies collected data after release from hospital. Due to variation in modes of drug administration, follow-up times, and ways of reporting changes in ICP, as well as no uniform definition of 'uncontrolled ICP', we did not perform meta-analysis for this outcome and report results narratively, by individual trial. Trials tended to report both treatments to be effective in reducing elevated ICP but that HTS had increased benefits, usually adding that pretreatment factors need to be considered (e.g. serum sodium and both system and brain hemodynamics). No trial provided data for our other outcomes of interest. Evidence for all outcomes is considered very low, as assessed by GRADE. All conclusions were downgraded due to imprecision (small sample size), indirectness (due to choice of measurement and/or selection of patients without TBI), and in some cases, risk of bias and inconsistency. Only one of the included trials reported data on adverse effects (AEs) - a rebound phenomenon, which was present only in the comparator group (mannitol). No data were reported on pulmonary oedema or acute renal failure during treatment. On the whole, investigators do not seem to have rigorously sought to collect data on AEs.

AUTHORS' CONCLUSIONS

This review set out to find trials comparing HTS to a potential range of other ICP-lowering agents, but only identified trials comparing it with mannitol or mannitol in combination with glycerol. Based on limited data, there is weak evidence to suggest that HTS is no better than mannitol in efficacy and safety in the long-term management of acute TBI. Future research should be comprised of large, multi-site trials, prospectively registered, reported in accordance with current best practice. Issues such as the type of TBI suffered by participants and concentration of infusion and length of time over which the infusion is given should be investigated.