Positive Fluid Balance Is Associated With Poor Outcomes in Subarachnoid Hemorrhage

Advances and Future Trends in the Diagnosis and Management of Subarachnoid Hemorrhage

Major advances in neurocritical care and the modalities used to treat aneurysms have led to improvement in the outlook of patients with aneurysmal subarachnoid hemorrhage. Yet, several knowledge gaps remain widely open. Variability in practices stems from the lack of solid evidence to guide management, which recent guidelines from professional organizations aim to mitigate. In this article, the authors review some of these gaps in knowledge, highlight important messages from recent management guidelines, emphasize aspects of our practice that we consider particularly useful to optimize patient outcomes, and suggest future areas of research.

A High Immediate Postoperative Neutrophil-to-Albumin Ratio is Associated With Unfavorable Clinical Outcomes at Hospital Discharge in Patients With Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Inflammation is associated with unfavorable clinical outcomes after aneurysmal subarachnoid hemorrhage (aSAH). We evaluated the relationship between postoperative neutrophil-to-albumin ratio (NAR) and unfavorable clinical outcomes (modified Rankin score ≥ 3) at hospital discharge in aSAH patients.

METHODS

Five hundred sixty aSAH patients undergoing surgical or endovascular treatment were included in this retrospective study. Patients were initially allocated to high (n=247) or low (n=313) postoperative NAR groups based on the immediate postoperative NAR cutoff value identified by receiver operating characteristic analysis, and then further subclassified into 4 groups: HH (high pre- and high postoperative NAR, n=156), LH (low preoperative and high postoperative NAR, n=91), HL (high preoperative and low postoperative NAR, n=68), and low pre- and low postoperative NAR (n=245).

RESULTS

Optimum cutoff values of immediate postoperative and preoperative NAR were 2.45 and 2.09, respectively. Unfavorable clinical outcomes were more frequent in patients with high compared with low postoperative NAR (45.3% vs. 13.4%; P < 0.001). In multivariate analysis, postoperative NAR was a significant predictor of unfavorable clinical outcomes (odds ratio, 2.10; 95% CI, 1.42-3.10; P < 0.001). Unfavorable clinical outcomes were less frequent in group low pre- and low postoperative NAR than in groups HH, LH, and HL (9.4% vs. 44.9%, 46.2% and 27.9%, respectively; all P < 0.001) and also in Group HL compared with groups HH and LH ( P =0.026 and P =0.030); clinical outcomes did not differ between Groups HH and LH.

CONCLUSIONS

A high immediate postoperative NAR was associated with unfavorable clinical outcomes at hospital discharge in aSAH patients.

Fluid therapy in the acute brain injured patient

Adequate fluid therapy in the acute brain injured (ABI) patient is essential for maintaining an adequate brain and systemic physiology and preventing intra- and extracranial complications. The target of euvolemia, implying avoidance of both hypovolemia and fluid overloading (or "hypervolemia," by definition associated with fluid extravasation leading to tissue edema) is of key importance. Primary brain injury can be aggravated by secondary brain injury and systemic deterioration through diverse pathways which can challenge appropriate fluid management, e.g. neuroendocrine and electrolyte disorders, stress cardiomyopathy (also known as cardiac stunning) and neurogenic pulmonary edema. This is an updated expert opinion aiming to provide a practical overview on fluid therapy in the ABI patient, partly based on more recent work and stressing the fact that intravenous fluids should be regarded as drugs, with their inherent potential for both benefit and (unintended) harm.

Prevention and Correction of Dysnatremia After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Dysnatremia occurs commonly in patients with aneurysmal subarachnoid hemorrhage (aSAH). The mechanisms for development of sodium dyshomeostasis are complex, including the cerebral salt-wasting syndrome, the syndrome of inappropriate secretion of antidiuretic hormone, diabetes insipidus. Iatrogenic occurrence of altered sodium levels plays a role, as sodium homeostasis is tightly linked to fluid and volume management.

METHODS

Narrative review of the literature.

RESULTS

Many studies have aimed to identify factors predictive of the development of dysnatremia, but data on associations between dysnatremia and demographic and clinical variables are variable. Furthermore, although a clear relationship between serum sodium serum concentrations and outcomes has not been established-poor outcomes have been associated with both hyponatremia and hypernatremia in the immediate period following aSAH and set the basis for seeking interventions to correct dysnatremia. While sodium supplementation and mineralocorticoids are frequently administered to prevent or counter natriuresis and hyponatremia, evidence to date is insufficient to gauge the effect of such treatment on outcomes.

CONCLUSIONS

In this article, we reviewed available data and provide a practical interpretation of these data as a complement to the newly issued guidelines for management of aSAH. Gaps in knowledge and future directions are discussed.

Insights into Hemodynamic Features of Survivors and the Deceased with Acute Brain Injury: A Step Forward Tailored Treatment

BACKGROUND

Pulmonary artery catheters are widely used for hemodynamical monitoring in critically ill patients. Acute brain injury is among the severe conditions treated in an intensive care unit. The advanced monitoring of hemodynamical parameters, fluid balance and adequate administered treatment based on those values are components of goal-directed therapy.

METHODS

A prospective observational study included adult patients who were hospitalized in the ICU due to acute bran injury, excluding brain oedema after cardiac arrest. Each patient had PAC inserted and hemodynamic data were collected during the first 3 days of the ICU stay every 6 h. Patients were divided into two groups based on the endpoint: the survivors and the deceased.

RESULTS

Length of stay in hospital differed between patiens. All patients, regardless of their outcome, had noradrenaline administered. The initial values of PAP differed between the groups (p = 0.05). There were positive correlations noticed between noradrenaline dose, CVP and fluid balance when compared to PCWP in a group of survivors and a positive correlation in the fluid balance when compared to PAP and PVRI. Lactate serum concentrations presented a correlation with the dose of noradrenaline in both groups.

CONCLUSIONS

Upon acute brain injury, values of PVRI and PAP increase. This is corelated with fluid load and worsened by an excessive fluid treatment in the case of an inconsiderate approach for stabilizing the patient hemodynamically. PAC may present limited advantages in terms of PAP and PVRI control during the treatment.

Effects of Fluids on the Sublingual Microcirculation in Sepsis

Sepsis is one of the most common and deadly syndromes faced in Intensive Care settings globally. Recent advances in bedside imaging have defined the changes in the microcirculation in sepsis. One of the most advocated interventions for sepsis is fluid therapy. Whether or not fluid bolus affects the microcirculation in sepsis has not been fully addressed in the literature. This systematic review of the evidence aims to collate studies examining the microcirculatory outcomes after a fluid bolus in patients with sepsis. We will assimilate the evidence for using handheld intra vital microscopes to guide fluid resuscitation and the effect of fluid bolus on the sublingual microcirculation in patients with sepsis and septic shock. We conducted a systematic search of Embase, CENTRAL and Medline (PubMed) using combinations of the terms "microcirculation" AND "fluid" OR "fluid resuscitation" OR "fluid bolus" AND "sepsis" OR "septic shock". We found 3376 potentially relevant studies. Fifteen studies published between 2007 and 2021 fulfilled eligibility criteria to be included in analysis. The total number of participants was 813; we included six randomized controlled trials and nine non-randomized, prospective observational studies. Ninety percent used Sidestream Dark Field microscopy to examine the microcirculation and 50% used Hydroxyethyl Starch as their resuscitation fluid. There were no clear effects of fluid on the microcirculation parameters. There was too much heterogeneity between studies and methodology to perform meta-analysis. Studies identified heterogeneity of affect in the sepsis population, which could mean that current clinical classifications were not able to identify different microcirculation characteristics. Use of microcirculation as a clinical endpoint in sepsis could help to define sepsis phenotypes. More research into the effects of different resuscitation fluids on the microcirculation is needed.

Early Goal-directed Therapy During Endovascular Coiling Procedures Following Aneurysmal Subarachnoid Hemorrhage: A Pilot Prospective Randomized Controlled Study

BACKGROUND

Maintenance of euvolemia and cerebral perfusion are recommended for the prevention of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (aSAH). We conducted a pilot randomized controlled study to assess the feasibility and efficacy of goal-directed therapy (GDT) to correct fluid and hemodynamic derangements during endovascular coiling in patients with aSAH.

METHODS

This study was conducted between November 2015 and February 2019 at a single tertiary center in Canada. Adult patients with aSAH within 5 days of aneurysm rupture were randomly assigned to receive either GDT or standard therapy during endovascular coiling. The incidence of dehydration at presentation and the efficacy of GDT were evaluated.

RESULTS

Forty patients were allocated to receive GDT (n=21) or standard therapy (n=19). Sixty percent of all patients were found to have dehydration before the coiling procedure commenced. Compared with standard therapy, GDT reduced the duration of intraoperative hypovolemia (mean difference 37.6 [95% confidence interval, 6.2-37.4] min, P=0.006) and low cardiac index (mean difference 30.7 [95% confidence interval, 9.5-56.9] min, P=0.035). There were no differences between the 2 treatment groups with respect to the incidence of vasospasm, stroke, death, and other complications up to postoperative day 90.

CONCLUSIONS

A high proportion of aSAH patients presented at the coiling procedure with dehydration and a low cardiac output state; these derangements were more likely to be corrected if the GDT algorithm was used. Compared with standard therapy, use of the GDT algorithm resulted in earlier recognition and more consistent treatment of dehydration and hemodynamic derangement during endovascular coiling.

Cerebral Autoregulation in Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating stroke subtype with a high rate of mortality and morbidity. The poor clinical outcome can be attributed to the biphasic course of the disease: even if the patient survives the initial bleeding emergency, delayed cerebral ischemia (DCI) frequently follows within 2 weeks time and levies additional serious brain injury. Current therapeutic interventions do not specifically target the microvascular dysfunction underlying the ischemic event and as a consequence, provide only modest improvement in clinical outcome. SAH perturbs an extensive number of microvascular processes, including the “automated” control of cerebral perfusion, termed “cerebral autoregulation.” Recent evidence suggests that disrupted cerebral autoregulation is an important aspect of SAH-induced brain injury. This review presents the key clinical aspects of cerebral autoregulation and its disruption in SAH: it provides a mechanistic overview of cerebral autoregulation, describes current clinical methods for measuring autoregulation in SAH patients and reviews current and emerging therapeutic options for SAH patients. Recent advancements should fuel optimism that microvascular dysfunction and cerebral autoregulation can be rectified in SAH patients.

Fluid management in patients undergoing neurosurgery

Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

Aneurysmal Subarachnoid Hemorrhage: Trends, Outcomes, and Predictions From a 15-Year Perspective of a Single Neurocritical Care Unit

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with disproportionally high mortality and long-term neurological sequelae. Management of patients with aSAH has changed markedly over the years, leading to improvements in outcome.

OBJECTIVE

To describe trends in aSAH care and outcome in a high-volume single center 15-yr cohort.

METHODS

All new admissions diagnosed with subarachnoid hemorrhage (SAH) to our tertiary neuro-intensive care unit between 2002 and 2016 were reviewed. Trend analysis was performed to assess temporal changes and a step-wise regression analysis was done to identify factors associated with outcomes.

RESULTS

Out of 3970 admissions of patients with SAH, 2475 patients proved to have a ruptured intracranial aneurysm. Over the years of the study, patient acuity increased by Hunt & Hess (H&H) grade and related complications. Endovascular therapies became more prevalent over the years, and were correlated with better outcome. Functional outcome overall improved, yet the main effect was noted in the low- and intermediate-grade patients. Several parameters were associated with poor functional outcome, including long-term mechanical ventilation (odds ratio 11.99, CI 95% [7.15-20.63]), acute kidney injury (3.55 [1.64-8.24]), pneumonia (2.89 [1.89-4.42]), hydrocephalus (1.80 [1.24-2.63]) diabetes mellitus (1.71 [1.04-2.84]), seizures (1.69 [1.07-2.70], H&H (1.67 [1.45-1.94]), and age (1.06 [1.05-1.07]), while endovascular approach to treat the aneurysm, compared with clip-ligation, had a positive effect (0.35 [0.25-0.48]).

CONCLUSION

This large, single referral center, retrospective analysis reveals important trends in the treatment of aSAH. It also demonstrates that despite improvement in functional outcome over the years, systemic complications remain a significant risk factor for poor prognosis. The historic H&H determination of outcome is less valid with today's improved care.

Dose-response association between fluid overload and in-hospital mortality in critically ill patients: a multicentre, prospective, observational cohort study

OBJECTIVES

Fluid management is important in ensuring haemodynamic stability in critically ill patients, but can easily lead to fluid overload (FO). However, the optimal fluid balance plot or range for critically ill patients is unknown. This study aimed to explore the dose-response relationship between FO and in-hospital mortality in critically ill patients.

DESIGN

Multicentre, prospective, observational study.

SETTING

Eighteen intensive care units (ICUs) of 16 tertiary hospitals in China.

PARTICIPANTS

Critically ill patients in the ICU for more than 3 days.

PRIMARY OUTCOME MEASURES AND ANALYSES

FO was defined as the ratio of the cumulative fluid balance (L) and initial body weight (kg) on ICU admission, expressed as a percentage. Maximum FO was defined as the peak value of FO during the first 3 days of ICU admission. Logistic regression models with restricted cubic splines were used to explore the pattern and magnitude of the association between maximum FO and risk of in-hospital mortality. Age, sex, Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score on admission, main diagnosis on admission to ICU, comorbidities, time of maximum FO, mechanical ventilation, renal replacement therapy, use of vasopressors and centres were adjusted in multivariable analysis.

RESULTS

A total of 3850 patients were included in the study, 929 (24.1%) of whom died in the hospital. For each 1% L/kg increase in maximum FO, the risk of in-hospital mortality increased by 4% (adjusted HR (aHR) 1.04, 95% CI 1.03 to 1.05, p<0.001). A maximum FO greater than 10% was associated with a 44% increased HR of in-hospital mortality compared with an FO less than 5% (aHR 1.44, 95% CI 1.27 to 1.67). Notably, we found a non-linear dose-response association between maximum FO and in-hospital mortality.

CONCLUSIONS

Both higher and negative fluid balance levels were associated with an increased risk of in-hospital mortality in critically ill patients.

TRIAL REGISTRATION NUMBER

ChiCTR-ECH-13003934.

Long-Term Outcomes of Elderly Patients with Poor-Grade Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Long-term outcomes after surgical treatment and intensive care have not been investigated in elderly patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to analyze 12-month outcomes and prognostic factors of patients with poor-grade aSAH who were at least age 70 years.

METHODS

We performed a single-center, retrospective study including poor-grade (World Federation of Neurological Societies [WFNS] grades IV and V) aSAH patients who were at least age 70 years, were admitted to our stroke center, and received aneurysmal treatment between April 2012 and September 2018. The clinical outcomes were evaluated at months 3 and 12. Univariate/multivariate analyses were performed to identify the independent prognostic factors of good neurologic outcomes (modified Rankin Scale score 0-3). These factors included sex, age, WFNS grade, Fisher group, delayed cerebral ischemia, aneurysm treatment, aneurysm size, aneurysm location, and blood examination data in the 14 days post subarachnoid hemorrhage.

RESULTS

The proportion of patients with good outcomes (modified Rankin Scale score 0-3) was increased at 12 months compared with that at 3 months. No intracerebral hemorrhage was a significant predictor of good neurologic outcomes at 3 months (P = 0.03). The absence of delayed cerebral ischemia and small fluctuations in the average absolute daily difference from normal sodium levels were significant predictors of good neurologic outcomes at months 3 and 12 (P = 0.04 and P = 0.03, respectively).

CONCLUSIONS

The absence of delayed cerebral ischemia and small fluctuations in the average absolute daily difference from the normal sodium levels were independently associated with good neurologic outcomes at 12 months in elderly patients. Intracerebral hemorrhage did not appear to affect long-term outcomes. These findings suggest that elderly patients with severe subarachnoid hemorrhage should not be excluded from receiving surgical treatment on the basis of their age alone.

Assessment of two prophylactic fluid strategies in aneurysmal subarachnoid hemorrhage: A randomized trial

OBJECTIVE

To compare the effect of two prophylactic euvolemic fluid strategy regimens on the incidence of cerebral vasospasm and clinical outcomes in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

Ninety-six patients with a basal intravenous intake of 15 mL/kg/day of Ringer's lactate solution were included, and an additional 15 to 50 mL/kg/day Ringer's lactate (RL-group) or hydroxyethyl starch 130/0.4 solution (HES-group) was administered to maintain the targeted mean arterial pressure. The primary end point was the occurrence of cerebral vasospasm during the first 14 days. The secondary end points were case fatality, Barthel's index, and Glasgow Outcome Scores (GOS) at 30 days after SAH.

RESULTS

Cerebral vasospasm developed in 42 patients (43.7%), and nine of these events were severe. The vasospasm rate among the RL- and HES-based groups was 25/48 and 17/48, respectively. For the secondary endpoint, four patients (4%) died by the end of follow-up (two in each group). Unfavorable outcome cases were not different in the RL and HES groups (9 vs. 14, respectively). There was no difference between the Barthel's scores at 30 days between the two groups.

CONCLUSIONS

Using starches in a prophylactic treatment strategy in aneurysmal SAH in not supported by the study.The trial was registered at Clinicaltrials.gov under the number NCT02064075.

Management of Subarachnoid Hemorrhage

Subarachnoid hemorrhage is an often devastating intracranial hemorrhage resulting from acute bleeding into the subarachnoid space. Although its overall incidence is less than that of acute ischemic stroke, sub-arachnoid hemorrhage carries increased risks of both mortality and disability. Although many patients with subarachnoid hemorrhage are transferred to specialty centers, they might initially present to small community-based hospitals. Treatment for these patients is complex, requiring specialized care and knowledge, and various complications can occur quickly and without warning. Therefore, all members of the health care team who care for these patients must understand proper management. Nurses in the intensive care unit play an important role in influencing outcomes, as they are best positioned to recognize neurological decline and provide rapid intervention. This article discusses the anatomy relevant to, and the epidemiology and pathophysiology of, subarachnoid hemorrhage and provides an overview of current evidence and clinical guidelines for managing this brain injury.

Fluid Balance Variations During the Early Phase of Large Hemispheric Stroke Are Associated With Patients' Functional Outcome

Background: From the variety of factors underlying the ischemia-associated edema formation in large hemispheric stroke (LHS), an increased brain water content during the early phase seems to have a pivotal role for long-lasting tissue damage. However, the importance of the fluid management during the acute phase of LHS has so far not been adequately studied. Therefore, this study explored the association between the fluid balance and functional outcome in patients suffering from LHS. Methods: We analyzed hospital-based medical records of 39 consecutive patients with LHS and decompressive hemicraniectomy. Over the first 10 days after admission, the volumes of all administered fluids were assessed daily and corrected for daily urinary output and insensible loss. Functional outcome at 3 months was assessed with the modified Rankin Scale (mRS) and dichotomized into an acceptable (mRS ≤ 4) vs. a poor outcome (mRS ≥ 5). Results: Compared to patients with a poor functional outcome (n = 19), those with an acceptable outcome (n = 20) were characterized by a significantly lower cumulative net fluid balance at day 5 (1.6 ± 2.5 vs. 3.4 ± 4.4 l), day 7 (2.0 ± 2.9 vs. 4.6 ± 5.2 l), and day 10 (0 ± 2.5 vs. 5.6 ± 6.2 l). In addition to age, only the cumulative net fluid balance at day 10 served as an independent factor for poor functional outcome in multiple regression analyses. Conclusion: These data provide evidence for a critical role of the early phase net fluid balance with respect to the functional outcome after LHS. This observation leads to the hypothesis that patients with LHS might benefit from a more restrictive volume therapy. However, prospective studies are warranted to establish a causal relationship and recommendations for treatment strategies.

Transpulmonary thermodilution monitoring-guided hemodynamic management improves cognitive function in patients with aneurysmal subarachnoid hemorrhage: a prospective cohort comparison

BACKGROUND

The effects of goal-directed hemodynamic management using transpulmonary thermodilution (TPT) monitor on the cognitive function of patients with aneurysmal subarachnoid hemorrhage (aSAH) remain unclear. The present study aimed to determine whether hemodynamic management with TPT monitor provides better cognitive function compared with standard hemodynamic management.

METHODS

Patients with aSAH who were admitted to the intensive care unit in 2016 were assigned to cohort 1, and those admitted in 2017 were assigned to cohort 2. In cohort 1, hemodynamic and fluid management was performed in accordance with the traditional pressure-based hemodynamic parameters and clinical examination, whereas in cohort 2, it was performed in accordance with the TPT monitor-measured flow-based parameters. The incidence of delayed cerebral ischemia (DCI) and pulmonary edema (PE) was determined. The functional outcome of patients was assessed using the modified Rankin scale (mRS) score and Montreal cognitive assessment (MoCA) test at 1 year following aSAH.

RESULTS

Cohort 1 included 45 patients and cohort 2 included 39 patients who completed the trial. The incidence of DCI (38% versus 26%) and PE (11% versus 3%) was comparable between the cohorts (p > 0.05). The mRS score was similar between the cohorts (p = 0.11). However, the MoCA score was 20.2 (19.2-21.4) and 23.5 (22.2-24.8) in cohort 1 and cohort 2, respectively (p < 0.001). Accordingly, the occurrence of poor MoCA score (38% versus 18%) was significantly lower in cohort 2 (p = 0.045).

CONCLUSIONS

TPT monitor-based hemodynamic management provides better cognitive outcome than standard hemodynamic management in patients with aSAH.

Fluid Intake But Not Fluid Balance Is Associated With Poor Outcome in Nontraumatic Subarachnoid Hemorrhage Patients

OBJECTIVES

Optimal fluid management is important in patients with acute brain injury, including subarachnoid hemorrhage. We aimed to examine the relationship between daily fluid intake and fluid balance with hospital complications and functional outcome.

DESIGN

Retrospective observational cohort study.

SETTING

Neurocritical care unit at a tertiary academic medical center.

PATIENTS

Two-hundred thirty-seven consecutive nontraumatic subarachnoid hemorrhage patients admitted to the neurologic ICU between 2010 and 2016.

INTERVENTIONS

Total daily amount of fluids and fluid balance were calculated over 15 days. Using multivariate generalized estimating equation models the association of daily fluid intake and fluid balance with disease severity, hospital complications and poor functional outcome (3-mo modified Rankin Score ≥ 3) was investigated. Additionally, we described the composition of fluids given.

MEASUREMENTS AND MAIN RESULTS

Patients presented with a median admission Hunt and Hess grade of 3 (interquartile range, 1-5) and were 57 years old (interquartile range, 47-67 yr old). A higher daily fluid intake was associated with higher admission Hunt and Hess grade (odds ratio, 1.61; 95% CI, 1.47-1.76; p < 0.001), increased pulmonary fluid accumulation (adjusted odds ratio, 1.11; 95% CI, 1.01-1.21; p = 0.033), prolonged mechanical ventilation (Wald statistic = 20.08; degrees of freedom = 1; p < 0.001), higher daily Subarachnoid hemorrhage Early Brain Edema Score (adjusted odds ratio, 1.11; 95% CI, 1.01-1.22; p = 0.034), occurrence of anemia (adjusted odds ratio, 1.36; 95% CI, 1.20-1.54; p < 0.001), delayed cerebral ischemia (adjusted odds ratio, 1.31; 95% CI, 1.14-1.51; p < 0.001), and poor functional outcome (adjusted odds ratio, 1.25; 95% CI, 1.10-1.41; p < 0.001). Daily fluid balance was associated with higher admission Hunt and Hess grade (odds ratio, 1.09; 95% CI, 1.05-1.13; p < 0.001) and anemia (adjusted odds ratio, 1.17; 95% CI, 1.03-1.33; p = 0.019). The main contributors to fluids were nutritional compounds (31%), IV drugs (30%), and volume substitution (17%).

CONCLUSIONS

Our study demonstrates a significant association of fluid intake but not fluid balance with hospital complications and poor functional outcome in subarachnoid hemorrhage patients. A larger prospective study is needed to confirm our results.

How is vasospasm screening using transcranial Doppler associated with delayed cerebral ischemia and outcomes in aneurysmal subarachnoid hemorrhage?

BACKGROUND

Delayed cerebral ischemia (DCI) is an independent predictor of an unfavorable outcome after aneurysmal subarachnoid hemorrhage (aSAH). Many centers, but not all, use transcranial Doppler (TCD) to screen for vasospasm to help predict DCI. We used the United Kingdom and Ireland Subarachnoid Haemorrhage (UKISAH) Registry to see if outcomes were better in centers that used TCD to identify vasospasm compared to those that did not.

METHODS

TCD screening practices were ascertained by national survey in 13 participating centers of the UKISAH. The routine use of TCD was reported by 5 "screening" centers, leaving 7 "non-screening" centers. Using a cross-sectional cohort study design, prospectively collected data from the UKISAH Registry was used to compare DCI diagnosis and favorable outcome (Glasgow Outcome Score 4 or 5) at discharge based on reported screening practice.

RESULTS

A cohort of 2028 aSAH patients treated ≤ 3 days of hemorrhage was analyzed. DCI was diagnosed in 239/1065 (22.4%) and 220/963 (22.8%) of patients in non-screening and screening centers respectively while 847/1065 (79.5%) and 648/963 (67.2%) achieved a favorable outcome. Odds ratios adjusted for age, injury severity, comorbidities, need for cerebrospinal fluid diversion, and re-bleed returned neutral odds of diagnosing DCI of 0.90 (95% CI 0.72-1.12; p value = 0.347) in screening units compared to those of non-screening units but significantly decreased odds of achieving a favorable outcome 0.56 (95% CI 0.42-0.82; p value < 0.001).

CONCLUSIONS

Centers that screened for vasospasm using TCD had poorer in-hospital outcomes and similar rates of DCI diagnosis compared to centers that did not.

Positive fluid balance is associated with increased in-hospital mortality in patients with intracerebral hemorrhage

Objective: This study aimed to investigate the association between fluid balance (FB) and in-hospital mortality in patients with intracerebral hemorrhage (ICH).Methods: Data were extracted from the online database Multi-parameter Intelligent Monitoring in Intensive Care III. Patients were divided into two groups according to the FB status at 48 hours after intensive care unit (ICU) admission: negative and positive 48-hour FB groups. The primary outcome was in-hospital mortality.Results: Data of 1407 patients were analyzed. Linear spline function in logistic models showed significant association between the volume of positive FB and in-hospital mortality (odds ratio (OR) 1.006; 95% CI: 1.002-1.010), while the association between the volume of negative FB and in-hospital mortality was non-significant. For interpretation, FB was further divided into four quartiles. Referred to Q1, the OR of in-hospital mortality stepwise increased from Q2 (OR, 1.11; 95% CI: 0.72-1.68) to Q4 (OR, 1.68; 95% CI: 1.13-2.48). A similar association was also found between FB and Glasgow coma scale at ICU discharge.Conclusions: In patients with ICH, increased volume of positive FB was associated with higher in-hospital mortality while the volume of negative FB was not. Whether maintaining a zero FB status is a beneficial strategy needs further investigation.

Fluid Management in Acute Brain Injury

PURPOSE OF THE REVIEW

The aims of fluid management in acute brain injury are to preserve or restore physiology and guarantee appropriate tissue perfusion, avoiding potential iatrogenic effects. We reviewed the literature, focusing on the clinical implications of the selected papers. Our purposes were to summarize the principles regulating the distribution of water between the intracellular, interstitial, and plasma compartments in the normal and the injured brain, and to clarify how these principles could guide fluid administration, with special reference to intracranial pressure control.

RECENT FINDINGS

Although a considerable amount of research has been published on this topic and in general on fluid management in acute illness, the quality of the evidence tends to vary. Intravascular volume management should aim for euvolemia. There is evidence of harm with aggressive administration of fluid aimed at achieving hypervolemia in cases of subarachnoid hemorrhage. Isotonic crystalloids should be the preferred agents for volume replacement, while colloids, glucose-containing hypotonic solutions, and other hypotonic solutions or albumin should be avoided. Osmotherapy seems to be effective in intracranial hypertension management; however, there is no clear evidence regarding the superiority of hypertonic saline over mannitol. Fluid therapy plays an important role in the management of acute brain injury patients. However, fluids are a double-edged weapon because of the potential risk of hyper-hydration, hypo- or hyper-osmolar conditions, which may unfavorably affect the clinical course and the outcome.

Hypotension and a positive fluid balance are associated with delirium in patients with shock

The pathogenesis of delirium in critically ill patients is multifactorial. How hypotension and hypoxemia affect brain function and whether they can promote delirium remains unclear. A high cumulative positive fluid balance may also have a negative effect on brain function and promote delirium. We hypothesized that delirium would be more likely to develop in patients with low systemic arterial pressure, hypoxemia and a higher positive fluid balance, and investigated these associations in a prospective observational cohort study in patients with shock. After initial resuscitation, episodes of hypotension, defined as a mean arterial pressure (MAP) <65 mmHg or diastolic pressure <60 mmHg, and hypoxemia, defined as peripheral oxygen saturation (SpO2) <90% for more than one minute or any arterial oxygen concentration (PaO2) <90 mmHg, were recorded during the first 5 days of the ICU stay. Fluid balance was evaluated daily and the 5-day cumulative fluid balance recorded. Delirium was assessed using the Confusion Assessment Method for the ICU. A total of 252 patients were admitted with shock during the study period; 185 (73%) developed delirium. Patients who developed delirium also had more episodes of hypotension with a low MAP (p = 0.013) or diastolic pressure (p = 0.018) during the first five days of the ICU stay than those who did not. Patients with a higher cumulative fluid balance during the same period were also more likely to develop delirium (p = 0.01); there was no significant difference in the occurrence of hypoxemia between groups. Joint modeling, combining a linear-mixed model and an adjusted Cox survival model showed that low diastolic pressure (alpha effect = -0.058±0.0013, p = 0.043) and a positive cumulative fluid balance (alpha effect = 0.04±0.003, p = 0.021) were independently associated with delirium. In conclusion, low diastolic pressure and a cumulative positive fluid balance but not hypoxemia were independently associated with development of delirium in patients with shock.

Postinterventional critical care management of aneurysmal subarachnoid hemorrhage

PURPOSE OF REVIEW

Subarachnoid hemorrhage from a ruptured aneurysm (aSAH) is a complex disorder with the potential to have devastating effects on the brain as well as other organ systems. After more than 3 decades of research, the underlying pathophysiologic mechanisms remain incompletely understood and important questions remain regarding the evaluation and management of these patients. The purpose of this review is to analyze the recent literature and improve our understanding of certain key clinical aspects.

RECENT FINDINGS

Growing body of evidence highlights the usefulness of CT perfusion scans in the diagnosis of vasospasm and delayed cerebral ischemia (DCI). Hypervolemia leads to worse cardiopulmonary outcomes and does not improve DCI. The traditional triple H therapy is falling out of favor with hemodynamic augmentation alone now considered the mainstay of medical management. Randomized controlled trials have shown that simvastatin and intravenous magnesium do not prevent DCI or improve functional outcomes after aneurysmal subarachnoid hemorrhage (aSAH). Emerging data using multimodality monitoring has further advanced our understanding of the pathophysiology of DCI in poor grade aSAH.

SUMMARY

The brief review will focus on the postinterventional care of aSAH patients outlining the recent advances over the past few years.

Medically induced hypertension, hypervolaemia and haemodilution for the treatment and prophylaxis of vasospasm following aneurysmal subarachnoid haemorrhage: systematic review

PURPOSE

Arterial vasospasm is a major cause of death and long-term disability following subarachnoid haemorrhage (SAH). The use of medically induced hypertension, hypervolaemia and/or haemodilution is widely practiced for prophylaxis and treatment of vasospasm following SAH. We aimed to determine if the quality of available research is adequate to inform use of haemodynamic management strategies to prevent or treat vasospasm following SAH.

METHODS

Individual searches of the following databases were conducted: The Cochrane Database of Systematic Reviews, The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and OpenSIGLE. Pertinent randomised clinical trials and cohort studies comparing any element or combination thereof: medically induced hypertension, hypervolaemia, and haemodilution were included. Data were extracted using standardised proformas and risk of bias assessed using a domain-based risk of bias assessment tool.

RESULTS

348 study reports were identified by our literature search. Eight studies were included, three of which examined both volume expansion and medically induced hypertension. Three randomised clinical trials and two cohort studies examining prophylactic volume expansion were included. Two trials of prophylactic medically induced hypertension and two cohort studies were included. One trial and one cohort study of medically induced hypertension for treatment of established vasospasm was included. These trials demonstrated no significant difference in any of the clinical outcome measures studied. No trials of blood transfusion were included.

CONCLUSIONS

There is currently insufficient evidence to determine the efficacy or non-efficacy of intravenous volume expansion, medically induced hypertension or blood transfusion for the treatment or prophylaxis of vasospasm following SAH. All of these approaches have been associated with adverse events, of unclear incidence. The current evidence base therefore cannot be used to reliably inform clinical practice. This is a priority for further research.

Continuous Infusion versus Intermittent Bolus Injection of Furosemide in Critically Ill Patients: A Systematic Review and Meta-analysis

OBJECTIVE

Fluid overload is a common phenomenon seen in intensive care units (ICUs). However, there is no general consensus on whether continuous or bolus furosemide is safer or more effective in these hemodynamically unstable ICU patients. The aim of this meta-analysis was to examine the clinical outcomes of continuous versus bolus furosemide in a critically ill population in ICUs.

DATA SOURCES

MEDLINE, EMBASE, PubMed, and the Cochrane Database of Systematic reviews were searched from their inception until June 2017.

REVIEW METHODS

All randomized controlled trials, observational studies, and case-control studies were included. Case reports, case series, nonsystematic reviews, and studies that involved children were excluded.

RESULTS

Nine studies (n = 464) were eligible in the data synthesis. Both continuous and bolus furosemide resulted in no difference in all-cause mortality (7 studies; n = 396; I² = 0%; fixed-effect model [FEM]: odds ratio [OR] 1.15 [95% confidence interval (CI) 0.67-1.96]; p = 0.64). Continuous furosemide was associated with significant greater total urine output (n = 132; I² = 70%; random-effect model: OR 811.19 [95% CI 99.84-1,522.53]; p = 0.03), but longer length of hospital stay (n = 290; I² = 40%; FEM: OR 2.84 [95% CI 1.74-3.94]; p < 0.01) in comparison to the bolus group. No statistical significance was found in the changes of creatinine and estimated glomerular filtration rate between both groups.

CONCLUSIONS

In this meta-analysis, continuous furosemide was associated with greater diuretic effect in total urine output as compared with bolus. Neither had any differences in mortality and changes of renal function tests. However, a large adequately powered randomized clinical trial is required to fill this knowledge gap.

Impact of restrictive fluid protocol on hypoxemia after aneurysmal subarachnoid hemorrhage

PURPOSE

In patients with aneurysmal subarachnoid hemorrhage (aSAH), acute cardiac dysfunction and triple-H-therapy, can lead to hypoxemia. Our aim was to assess impact of a protocoled fluid restrictive approach on hypoxemia in these patients.

METHODS

We included prospectively ICU patients with aSAH admitted within 24h after the bleed. The study was divided into 2 phases. The first phase, from January to December 2012, was designated as control group (group C). The second phase, from February 2014 to January 2015, was designated as study group (group S). Between these periods, a protocoled fluid intake approach was implemented to maintain as low as possible the cumulative fluid balances.

RESULTS

Effective fluid restriction was obtained: at day 3 cumulative fluid balances were respectively for group C and group S, 1559±2402ml and 759±1855ml (p=0.04); and 2211±4918ml vs 529±2806ml (p=0.04) at day 7. We observed reduction in proportion of hypoxemic patient in group S compared to group C, at day 3 (22% vs 40%, p=0.047) and at day 7 (28% vs 57%, p=0.007).

CONCLUSIONS

Fluid restrictive management of patients with aSAH decreases number of hypoxemic patients at day 3 and day 7.

Safe Brain Tumor Resection Does not Depend on Surgery Alone - Role of Hemodynamics

Aim of this study was to determine if perioperative hemodynamics have an impact on perioperative infarct volume and patients’ prognosis. 201 cases with surgery for a newly diagnosed or recurrent glioblastoma were retrospectively analyzed. Clinical data and perioperative hemodynamic parameters, blood tests and time of surgery were recorded. Postoperative infarct volume was quantitatively assessed by semiautomatic segmentation. Mean diastolic blood pressure (dBP) during surgery (rho −0.239, 95% CI −0.11 – −0.367, p = 0.017), liquid balance (rho 0.236, 95% CI 0.1–0.373, p = 0.017) and mean arterial pressure (MAP) during surgery (rho −0.206, 95% CI −0.07 – −0.34, p = 0.041) showed significant correlation to infarct volume. A rank regression model including also age and recurrent surgery as possible confounders revealed mean intraoperative dBP, liquid balance and length of surgery as independent factors for infarct volume. Univariate survival analysis showed mean intraoperative dBP and MAP as significant prognostic factors, length of surgery also remained as significant prognostic factor in a multivariate model. Perioperative close anesthesiologic monitoring of blood pressure and liquid balance is of high significance during brain tumor surgery and should be performed to prevent or minimize perioperative infarctions and to prolong survival.

Association between fluid intake and mortality in critically ill patients with negative fluid balance: a retrospective cohort study

Background

Compared to positive fluid balance (FB), negative FB is associated with improved clinical outcomes in critically ill patients. However, as to whether achieving more negative FB can further improve outcomes has not been investigated. This study aimed to investigate whether more negative FB and restricted fluid intake were associated with improved outcomes in critically ill patients.

Method

Data were extracted from the Multi-parameter Intelligent Monitoring in Intensive Care III Database. Patients achieving negative FB at 48 hours after intensive care unit (ICU) admission were screened. The primary outcome was hospital mortality. Logistic models were built to explore the association between FB, fluid intake and mortality, using FB and fluid intake (both four levels) as design variables and using the linear spline function method.

Results

There were 2068 patients meeting the inclusion criteria. Compared to slight negative FB (level 1), there was a decreased tendency towards mortality with FB level 2 (OR 0.88, 95% CI 0.69–1.11) and level 3 (OR 0.79, 95% CI 0. 65–1.11); however, only extreme negative FB (level 4) was significant (OR 0.56, 95% CI 0. 33–0.95). Fluid intake and urine output were evenly distributed over the first 48 hours after ICU admission. Fluid intake was inversely associated with hospital mortality, with the OR decreased stepwise from level 2 (OR 0.73, 95% CI 0.56–0.96) to level 4 (OR 0.47, 95% CI 0.30–0.74), referred to level 1. Urine output also showed a similar pattern. Diuretic use was associated with higher mortality in both models.

Conclusion

In critically ill patients with negative FB, both increased fluid intake and urine output were associated with decreased hospital mortality. However, compared to slight FB, achieving more negative FB was not associated with reduced mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1692-3) contains supplementary material, which is available to authorized users.

Mid-regional pro-adrenomedullin (MR-proADM), a marker of positive fluid balance in critically ill patients: results of the ENVOL study

Background

The optimal control of blood volume without fluid overload is a main challenge in the daily care of intensive care unit (ICU) patients. Accordingly this study focused on the identification of biomarkers to help characterize fluid overload status.

Methods

Sixty-seven patients were studied from ICU admission to day 7 (D₇). Blood and urine samples were taken daily and sodium and water balance strictly calculated resulting in a total cumulative assessment of ∆Na⁺ and ∆H₂O. Furthermore, plasmatic biomarkers (cortisol, epinephrine, norepinephrine, renin, angiotensin II, aldosterone, pro-endothelin, copeptine, atrial natriuretic peptide, erythropoietin, mid-regional pro-adrenomedullin (MR-proADM)) and Sequential Organ Failure Assessment (SOFA) scores were measured at D₂, D₅ and D₇. Blood volumes were measured with ⁵¹Cr fixed on red blood cells at D₂ and D₇.

Results

The ∆Na⁺ or ∆H₂O were increased in all patients but never related to blood volumes at D₂ nor D₇. Total blood volumes were at normal values with constantly low red blood cell volumes and normal or decreased plasmatic volume. Weight, plasmatic proteins, and hemoglobin were weakly related to ∆Na⁺ or ∆H₂O. Amongst all tested biomarkers, only MR-proADM was related to sodium and fluid overload. This biomarker was also a predictor of SOFA scores.

Conclusions

Plasmatic concentration in MR-proADM seems to be a good surrogate for evaluation of ∆Na⁺ or ∆H₂O and predicts sodium and extracellular fluid overload.

Trial registration

ClinicalTrials.gov: NCT01858675 in May 13, 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1540-x) contains supplementary material, which is available to authorized users.

Management of delayed cerebral ischemia after subarachnoid hemorrhage

For patients who survive the initial bleeding event of a ruptured brain aneurysm, delayed cerebral ischemia (DCI) is one of the most important causes of mortality and poor neurological outcome. New insights in the last decade have led to an important paradigm shift in the understanding of DCI pathogenesis. Large-vessel cerebral vasospasm has been challenged as the sole causal mechanism; new hypotheses now focus on the early brain injury, microcirculatory dysfunction, impaired autoregulation, and spreading depolarization. Prevention of DCI primarily relies on nimodipine administration and optimization of blood volume and cardiac performance. Neurological monitoring is essential for early DCI detection and intervention. Serial clinical examination combined with intermittent transcranial Doppler ultrasonography and CT angiography (with or without perfusion) is the most commonly used monitoring paradigm, and usually suffices in good grade patients. By contrast, poor grade patients (WFNS grades 4 and 5) require more advanced monitoring because stupor and coma reduce sensitivity to the effects of ischemia. Greater reliance on CT perfusion imaging, continuous electroencephalography, and invasive brain multimodality monitoring are potential strategies to improve situational awareness as it relates to detecting DCI. Pharmacologically-induced hypertension combined with volume is the established first-line therapy for DCI; a good clinical response with reversal of the presenting deficit occurs in 70 % of patients. Medically refractory DCI, defined as failure to respond adequately to these measures, should trigger step-wise escalation of rescue therapy. Level 1 rescue therapy consists of cardiac output optimization, hemoglobin optimization, and endovascular intervention, including angioplasty and intra-arterial vasodilator infusion. In highly refractory cases, level 2 rescue therapies are also considered, none of which have been validated. This review provides an overview of current state-of-the-art care for DCI management.

Case Studies in Neurocritical Care

The practice of neurocritical care encompasses multiple acute neurologic and neurosurgical diseases and requires detailed knowledge of neurology and critical care. This article presents 5 cases that illustrate just some of the conditions encountered in the daily practice of neurocritical care and exemplify some of the common diagnostic, therapeutic, and prognostic challenges facing the neurointensivist. Life-threatening medical complications after severe acute ischemic stroke, seizures and extreme agitation from autoimmune encephalitis, refractory seizures after subdural hemorrhage, neurologic and systemic complications related to aneurysmal subarachnoid hemorrhage, and status epilepticus after cardiac arrest are discussed in this article.

Fluid management of the neurological patient: a concise review

Maintenance fluids in critically ill brain-injured patients are part of routine critical care. Both the amounts of fluid volumes infused and the type and tonicity of maintenance fluids are relevant in understanding the impact of fluids on the pathophysiology of secondary brain injuries in these patients. In this narrative review, current evidence on routine fluid management of critically ill brain-injured patients and use of haemodynamic monitoring is summarized. Pertinent guidelines and consensus statements on fluid management for brain-injured patients are highlighted. In general, existing guidelines indicate that fluid management in these neurocritical care patients should be targeted at euvolemia using isotonic fluids. A critical appraisal is made of the available literature regarding the appropriate amount of fluids, haemodynamic monitoring and which types of fluids should be administered or avoided and a practical approach to fluid management is elaborated. Although hypovolemia is bound to contribute to secondary brain injury, some more recent data have emerged indicating the potential risks of fluid overload. However, it is acknowledged that many factors govern the relationship between fluid management and cerebral blood flow and oxygenation and more research seems warranted to optimise fluid management and improve outcomes.

Neurocritical care for intracranial haemorrhage: a systematic review of recent studies

Intracerebral haemorrhage (ICH) is associated with significant early mortality (up to 50% at 30 days) and long-term morbidity (with permanent neurological deficits in 75-80% of patients) and represents a serious health issue worldwide. The past decade has seen a dramatic increase in clinical research on ICH diagnosis and treatment that has led to revision of the guidelines for the diagnosis and management of ICH from the American Heart Association and American Stroke Association in 2013. This systematic review reports recent clinical evidence (original studies published between September 2013 and July 2015) related to neurocritical care and intensive care unit management of patients with ICH. All but one publication included in this review report original studies related to managment of patients with intracerebral or subarachnoid haemorrhage. These include insights on risk stratification and neurocritical care or intensive care unit treatment, management of haemodynamic variables and mechanical ventilation (goal-directed fluid therapy, advanced haemodynamic monitoring, and avoidance of hyperoxia and hyperventilation), and pharmacological neuroprotection.