Fever burden and functional recovery after subarachnoid hemorrhage

Clinical experience with bromocriptine for central hyperthermia after brain insult

INTRODUCTION

Bromocriptine is a dopamine receptor agonist used for central hyperthermia with limited data. We describe our single-center experience utilizing bromocriptine for central hyperthermia, including the population treated, most common dosing regimens, adverse events, and discontinuation reasons.

METHODS

A retrospective study was conducted screening patients who were admitted to intensive care units for acute neurological insults and administered bromocriptine for central hyperthermia between April 2016 and September 2022. Baseline characteristics, disease severity markers, and bromocriptine doses were collected. Body temperatures prior to the first dose of bromocriptine, at the time of dose, and after each dose were recorded. Co-administration of additional hyperthermia management therapies was noted.

RESULTS

Thirty patients were included. The most common diagnosis was traumatic brain injury (TBI) (N = 14). The most common reason for discontinuation was resolution of indication (N = 14). Discontinuation due to mild adverse effects occurred in four patients; hepatotoxicity was the most common. There was a paired mean difference of -0.37°C (p = 0.005) between temperatures before and after bromocriptine initiation.

CONCLUSION

Bromocriptine is a potential therapy for the management of central hyperthermia in patients with severe acute neurologic insults who have failed other therapies. Bromocriptine was well tolerated and associated with a low incidence of adverse events.

Beyond Control: Temperature Burden in Patients with Spontaneous Subarachnoid Hemorrhage-An Observational Study

BACKGROUND

Temperature abnormalities are common after spontaneous subarachnoid hemorrhage (SAH). Here, we aimed to describe the evolution of temperature burden despite temperature control and to assess its impact on outcome parameters.

METHODS

This retrospective observational study of prospectively collected data included 375 consecutive patients with SAH admitted to the neurological intensive care unit between 2010 and 2022. Daily fever (defined as the area over the curve above 37.9 °C multiplied by hours with fever) and spontaneous hypothermia burden (< 36.0 °C) were calculated over the study period of 16 days. Generalized estimating equations were used to calculate risk factors for increased temperature burdens and the impact of temperature burden on outcome parameters after correction for predefined variables.

RESULTS

Patients had a median age of 58 years (interquartile range 49-68) and presented with a median Hunt & Hess score of 3 (interquartile range 2-5) on admission. Fever (temperature > 37.9 °C) was diagnosed in 283 of 375 (76%) patients during 14% of the monitored time. The average daily fever burden peaked between days 5 and 10 after admission. Higher Hunt & Hess score (p = 0.014), older age (p = 0.033), and pneumonia (p = 0.022) were independent factors associated with delayed fever burden between days 5 and 10. Increased fever burden was independently associated with poor 3-month functional outcome (modified Rankin Scale 3-6, p = 0.027), poor 12-month functional outcome (p = 0.020), and in-hospital mortality (p = 0.045), but not with the development of delayed cerebral ischemia (p = 0.660) or intensive care unit length of stay (p = 0.573). Spontaneous hypothermia was evident in the first three days in patients with a higher Hunt & Hess score (p < 0.001) and intraventricular hemorrhage (p = 0.047). Spontaneous hypothermia burden was not associated with poor 3-month outcome (p = 0.271).

CONCLUSIONS

Early hypothermia was followed by fever after SAH. Increased fever time burden was associated with poor functional outcome after SAH and could be considered for neuroprognostication.

Hypothermia on the first day of ICU admission leads to increased in-hospital mortality in patients with subarachnoid hemorrhage

The relationship between early spontaneous hypothermia and adverse clinical outcomes in patients with subarachnoid hemorrhage (SAH) has not been paid much attention. We designed this retrospective cohort study to determine this relationship by analyzing the association between the lowest body temperature (T-lowest) on the first day of ICU admission and in-hospital mortality. In this study, 550 participants with non-traumatic SAH were chosen from the Medical Information Mart for Intensive Care (MIMIC)-IV database. Multivariate Cox regression analysis showed that T-lowest was nonlinearity correlated with in-hospital mortality (HR = 0.72, 95% CI: 0.59-0.86, p < 0.001). We divided the T-lowest into quartile groups. In comparison to reference group Q1 (31.30-36.06 ℃), group Q3 (36.56-36.72 ℃) had a 50% lower risk of death in the hospital (HR: 0.5, 95% CI: 0.28-0.87, p = 0.014). We further confirmed the curve-like relationship between T-lowest and in-hospital mortality using restricted cubic splines. The mortality is lowest when the T-lowest is close to 36.5 °C, and the risk of death is increased when the temperature is lower or higher than that. Our study demonstrates that in-hospital mortality is associated with T-lowest. Patients with non-traumatic SAH are at increased risk of death if their body temperature on the first day of ICU admission is too low.

Three Pillars of Recovery After Aneurysmal Subarachnoid Hemorrhage: A Narrative Review

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurologic disease with high mortality and disability. There have been global improvements in survival, which has contributed to the prevalence of patients living with long-term sequelae related to this disease. The focus of active research has traditionally centered on acute treatment to reduce mortality, but now there is a great need to study the course of short- and long-term recovery in these patients. In this narrative review, we aim to describe the core pillars in the preservation of cerebral function, prevention of complications, the recent literature studying neuroplasticity, and future directions for research to enhance recovery outcomes following aSAH.

Burden of fever and hospital mortality in patients admitted to the intensive care unit with isolated traumatic brain injury-A retrospective cohort study using continuous temperature data

BACKGROUND

Fever has been shown to be associated with poor outcomes in patients with traumatic brain injury. Earlier studies have used peak daily temperature to derive the burden of fever. The association between hospital mortality and fever burden calculated as the area under the temperature-time curve for the entire duration of intensive care unit (ICU) stay has not been studied before.

OBJECTIVES

The objective of this study was to investigate the association between the burden of fever and hospital mortality in patients with isolated traumatic brain injury admitted to the ICU.

METHODS

We conducted this retrospective cohort study using an electronic database in a tertiary ICU in Sydney. We included all adult patients admitted to the ICU with isolated traumatic brain injury over 3 years from 1 July 2017 to 30 June 2020. We collected data on demographics, clinical characteristics, and interventions for all patients. We defined the burden of fever as an area under the temperature-time curve above 37 °C. The primary outcome was hospital mortality. We used multivariable logistic regression to determine the association between burden of fever and hospital mortality. We assessed the importance of the burden of fever in a predictive model using machine-learning methods (Bagging and Random Forest).

RESULTS

A total of 88 patients (76% males, mean age: 54 ± 23 years, mean Acute Physiology and Chronic Health Evaluation [APACHE] II score: 15 ± 7) were included in the study, and 18 (20.5%) of the 88 patients died in hospital. Compared to survivors, the nonsurvivors had lower mean Glasgow Coma Scale (GCS) score at the scene, higher mean APACHE II and III scores, and higher rates of intracranial pressure monitoring, surgery, mechanical ventilation, use of vasopressors, and cooling. On multivariable logistic regression, age (odds ratio: 1.05, 95% confidence interval: 1.02-1.09, p = 0.01) was found to be an independent predictor of hospital mortality. A higher GCS score at the scene (odds ratio: 0.81, 95% confidence interval: 0.66-0.98, p = 0.03) was associated with survival. The burden of fever was not associated with hospital mortality. The top three important variables in the predictive model were APACHE III, GCS score at scene, and age.

CONCLUSION

The burden of fever was not an independent predictor of hospital mortality. The results of this study need to be confirmed in a large multicenter study.

Temperature Changes in Poor-Grade Aneurysmal Subarachnoid Hemorrhage: Relation to Injury Pattern, Intracranial Pressure Dynamics, Cerebral Energy Metabolism, and Clinical Outcome

BACKGROUND

The aim was to study the course of body temperature in the acute phase of poor-grade aneurysmal subarachnoid hemorrhage (aSAH) in relation to the primary brain injury, cerebral physiology, and clinical outcome.

METHODS

In this observational study, 166 patients with aSAH treated at the neurosurgery department at Uppsala University Hospital in Sweden between 2008 and2018 with temperature, intracranial pressure (ICP), and microdialysis (MD) monitoring were included. The first 10 days were divided into the early phase (days 1-3) and the vasospasm phase (days 4-10).

RESULTS

Normothermia (temperature = 36-38 °C) was most prevalent in the early phase. A lower mean temperature at this stage was univariately associated with a worse primary brain injury, with higher Fisher grade and higher MD glycerol concentration, as well as a worse neurological recovery at 1 year. There was otherwise no association between temperature and cerebral physiological variables in the early phase. There was a transition toward an increased burden of hyperthermia (temperature > 38 °C) in the vasospasm phase. This was associated with concurrent infections but not with neurological or radiological injury severity at admission. Elevated temperature was associated with higher MD pyruvate concentration, lower rate of an MD pattern indicative of ischemia, and higher rate of poor neurological recovery at 1 year. There was otherwise no association between temperature and cerebral physiological variables in the vasospasm phase. The associations between temperature and clinical outcome did not hold true in multiple logistic regression analyses.

CONCLUSIONS

Spontaneously low temperature in the early phase reflected a worse primary brain injury and indicated a worse outcome prognosis. Hyperthermia was common in the vasospasm phase and was more related to infections than primary injury severity but also with a more favorable energy metabolic pattern with better substrate supply, possibly related to hyperemia.

Intracranial Pressure Monitoring and Management in Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage is a medical condition that can lead to intracranial hypertension, negatively impacting patients' outcomes. This review article explores the underlying pathophysiology that causes increased intracranial pressure (ICP) during hospitalization. Hydrocephalus, brain swelling, and intracranial hematoma could produce an ICP rise. Although cerebrospinal fluid withdrawal via an external ventricular drain is commonly used, ICP monitoring is not always consistently practiced. Indications for ICP monitoring include neurological deterioration, hydrocephalus, brain swelling, intracranial masses, and the need for cerebrospinal fluid drainage. This review emphasizes the importance of ICP monitoring and presents findings from the Synapse-ICU study, which supports a correlation between ICP monitoring and treatment with better patient outcomes. The review also discusses various therapeutic strategies for managing increased ICP and identifies potential areas for future research.

2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage: A Guideline From the American Heart Association/American Stroke Association

AIM

The "2023 Guideline for the Management of Patients With Aneurysmal Subarachnoid Hemorrhage" replaces the 2012 "Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage." The 2023 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with aneurysmal subarachnoid hemorrhage.

METHODS

A comprehensive search for literature published since the 2012 guideline, derived from research principally involving human subjects, published in English, and indexed in MEDLINE, PubMed, Cochrane Library, and other selected databases relevant to this guideline, was conducted between March 2022 and June 2022. In addition, the guideline writing group reviewed documents on related subject matter previously published by the American Heart Association. Newer studies published between July 2022 and November 2022 that affected recommendation content, Class of Recommendation, or Level of Evidence were included if appropriate. Structure: Aneurysmal subarachnoid hemorrhage is a significant global public health threat and a severely morbid and often deadly condition. The 2023 aneurysmal subarachnoid hemorrhage guideline provides recommendations based on current evidence for the treatment of these patients. The recommendations present an evidence-based approach to preventing, diagnosing, and managing patients with aneurysmal subarachnoid hemorrhage, with the intent to improve quality of care and align with patients' and their families' and caregivers' interests. Many recommendations from the previous aneurysmal subarachnoid hemorrhage guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Fine tuning of neurointensive care in aneurysmal subarachnoid hemorrhage: From one-size-fits-all towards individualized care

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe type of acute brain injury with high mortality and burden of neurological sequelae. General management aims at early aneurysm occlusion to prevent re-bleeding, cerebrospinal fluid drainage in case of increased intracranial pressure and/or acute hydrocephalus, and cerebral blood flow augmentation in case of delayed ischemic neurological deficits. In addition, the brain is vulnerable to physiological insults in the acute phase and neurointensive care (NIC) is important to optimize the cerebral physiology to avoid secondary brain injury. NIC has led to significantly better neurological recovery following aSAH, but there is still great room for further improvements. First, current aSAH NIC management protocols are to some extent extrapolated from those in traumatic brain injury, notwithstanding important disease-specific differences. Second, the same NIC management protocols are applied to all aSAH patients, despite great patient heterogeneity. Third, the main variables of interest, intracranial pressure and cerebral perfusion pressure, may be too superficial to fully detect and treat several important pathomechanisms. Fourth, there is a lack of understanding not only regarding physiological, but also cellular and molecular pathomechanisms and there is a need to better monitor and treat these processes. This narrative review aims to discuss current state-of-the-art NIC of aSAH, knowledge gaps in the field, and future directions towards a more individualized care in the future.

Fever management in acute brain injury

PURPOSE OF REVIEW

Fever is common after acute brain injury and is associated with poor prognosis in this setting.

RECENT FINDINGS

Achieving normothermia is feasible in patients with ischemic or hemorrhagic stroke, subarachnoid hemorrhage and traumatic brain injury. Pharmacological strategies (i.e. paracetamol or nonsteroidal anti-inflammatory drugs) are frequently ineffective and physical (i.e. cooling devices) therapies are often required. There are no good quality data supporting any benefit from therapeutic strategies aiming at normothermia in all brain injured patients when compared with standard of care, where mild-to-moderate fever is tolerated. However, recent guidelines recommended fever control in this setting.

SUMMARY

As fever is considered a clinically relevant secondary brain damage, we have provided an individualized therapeutic approach to treat it in brain injured patients, which deserved further validation in the clinical setting.

Predictive Relevance of Early Temperature Elevation on the Risk of Delayed Cerebral Ischemia Development Following Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Fever in aneurysmal subarachnoid hemorrhage (aSAH) has been associated with delayed cerebral ischemia (DCI), but its relevance in risk stratification has not been explored. This study investigated whether early temperature elevation following aSAH predicts impending clinical deterioration caused by DCI.

METHODS

Relevant cases were identified from a prospectively maintained database for consecutive patients with aSAH treated at our center between July 2015 and January 2020. Temperature readings obtained every 2 hours for individual patients from admission through day 14 were recorded and analyzed. Demographic, clinical, treatment, and angiographic data were extracted from the electronic medical record. The primary end point was the occurrence of DCI (clinical and radiographic vasospasm). Multivariate logistic regression analyses were performed to account for patient age, smoking status, and VASOGRADE classification.

RESULTS

The study included 175 patients (124 women) with aSAH. The median age at diagnosis was 55.4 years (range, 20.5-87.2 years). Clinical DCI occurred in 58 patients; 2 (1.1%) responded to hemodynamic augmentation, and 56 (32.0%) required intra-arterial therapy. Temperature graphs showed a marked divergence on day 4 between clinical DCI and non-DCI groups (1.12°C ± 0.15°C and 0.76°C ± 0.08°C, respectively, P = 0.007). Patients with temperature elevation ≥2.5°C on day 4 or 5 compared with their admission temperature were more likely to clinically deteriorate owing to DCI (odds ratio 4.55, 95% confidence interval 1.31-15.77, P = 0.017).

CONCLUSIONS

Temperature elevation of ≥2.5°C on day 4 or 5 compared with baseline suggests a greater risk of clinical deterioration owing to DCI.

Temperature management in acute brain injury: A systematic review of clinical evidence

Temperature alterations in neurocritical care settings are common and have a striking effect on brain metabolism leading to or exacerbating neuronal injury. Hyperthermia worsens acute brain injury (ABI) patients outcome. However conclusive evidence linking control of temperature to improved outcome is still lacking. This review article report an update -results from clinical studies published between March 2006 and March 2020- on the relationship between hyperthermia or Target Temperature Management and functional outcome or mortality in ABI patients.

MATERIALS AND METHODS

A systematic search of articles in PubMed and EMBASE database was accomplished. Only complete studies, published in English in peer-reviewed journals were included.

RESULTS

A total of 63 articles into 5 subchapters are presented: acute ischemic stroke (17), subarachnoid hemorrhage (14), brain trauma (14), intracranial hemorrhage (8), and mixed acute brain injury (10). This evidence confirm and extend the negative impact of hyperthermia in ABI patients on worse functional outcome and higher mortality. In particular "early hyperthermia" in AIS patients seems to have a protective role have as promoting factor of clot lysis but no conclusive evidence is available. Normothermic TTM seems to have a positive effect on TBI patients in a reduced mortality rate compared to hypothermic TTM.

CONCLUSIONS

Hyperthermia in ABI patients is associated with worse functional outcome and higher mortality. The use of normothermic TTM has an established indication only in TBI; further studies are needed to define the role and the indications of normothermic TTM in ABI patients.

Defining the Mechanism of Subarachnoid Hemorrhage-Induced Pyrexia

Fever can affect the majority of patients with subarachnoid hemorrhage (SAH) and many times no identifiable source is found for the fever whether infectious or sterile, like deep vein thrombosis. We hypothesized that fever in SAH is mediated by a NON-cyclo-oxygenase-dependent mechanism, which we neologized as subarachnoid hemorrhage-induced pyrexia (SAHiP). This hypothesis was investigated using genetically modified mice, pharmacological manipulation, cerebrospinal fluid from SAH patients, and a large cohort of SAH patients. Mice with deletions of neuronal prostaglandin EP3 receptor, global toll-like receptor 4 (TLR4), myeloid TLR4, and microglial TLR4 were subjected to SAH after being implanted with thermometers. Pathways necessary for SAHiP were identified. In SAH patients, cerebrospinal fluid was examined by flow cytometry and correlated with SAHiP. From a large cohort of SAH patients, independent associations with SAHiP were determined using logistic regression analysis. In our mouse model of SAH, microglial TLR4 is necessary for SAHiP, but independent of the neuronal prostaglandin EP3 receptor, cyclo-oxygenase, and prostaglandins. Macrophages from the cerebrospinal fluid of SAH patients with SAHiP expressed more TLR4-co-receptor than SAH patients without SAHiP. In a large cohort of SAH patients, SAHiP was found to be independently, yet inversely, associated with acetaminophen administration. SAHiP is independent of the neuronal prostaglandin EP3 receptor, cyclo-oxygenase, and prostaglandins, but dependent on microglial/macrophage TLR4 with evidence from both SAH mouse models and SAH patients.

Admission Heart Rate Variability is Associated with Fever Development in Patients with Intracerebral Hemorrhage

BACKGROUND

Fever is associated with worse outcome after intracerebral hemorrhage (ICH). Autonomic dysfunction, commonly seen after brain injury, results in reduced heart rate variability (HRV). We sought to investigate whether HRV was associated with the development of fever in patients with ICH.

METHODS

We prospectively enrolled consecutive patients with spontaneous ICH in a single-center observational study. We included patients who presented directly to our emergency department after symptom onset, had a 10-second electrocardiogram (EKG) performed within 24 h of admission, and were in sinus rhythm. Patient temperature was recorded every 1-4 h. We defined being febrile as having a temperature of ≥ 38 °C within the first 14 days, and fever burden as the number of febrile days. HRV was defined by the standard deviation of the R-R interval (SDNN) measured on the admission EKG. Univariate associations were determined by Fisher's exact, Mann-Whitney U, or Spearman's rho correlation tests. Variables associated with fever at p ≤ 0.2 were entered in a logistic regression model of being febrile within 14 days.

RESULTS

There were 248 patients (median age 63 [54-74] years, 125 [50.4%] female, median ICH Score 1 [0-2]) who met the inclusion criteria. Febrile patients had lower HRV (median SDNN: 1.72 [1.08-3.60] vs. 2.55 [1.58-5.72] msec, p = 0.001). Lower HRV was associated with more febrile days (R = - 0.22, p < 0.001). After adjustment, lower HRV was independently associated with greater odds of fever occurrence (OR 0.92 [95% CI 0.87-0.97] with each msec increase in SDNN, p = 0.002).

CONCLUSIONS

HRV measured on 10-second EKGs is a potential early marker of parasympathetic nervous system dysfunction and is associated with subsequent fever occurrence after ICH. Detecting early parasympathetic dysfunction may afford opportunities to improve ICH outcome by targeting therapies at fever prevention.

Fever Burden and Health-Related Quality of Life After Intracerebral Hemorrhage

BACKGROUND

Fever is associated with worse functional outcomes after intracerebral hemorrhage (ICH); however, there are few prospective data to quantify the relationship with health-related quality of life (HRQoL). We tested the hypothesis that increased burden of fever is independently associated with decreased HRQoL at follow-up.

METHODS

In this prospective observational cohort study of 106 ICH patients admitted to a tertiary care hospital between 2011 and 2015, we recorded the highest core temperature each calendar day for 14 days after ICH onset. Fever burden was defined as the number of days with a fever ≥ 100.4 °F (38 °C). HRQoL outcomes were measured with Neuro-QoL domains of Cognitive Function and Mobility at 28 days, 3 months, and 1 year. Results were analyzed using mixed effects regression analysis.

RESULTS

Each additional day with a fever was independently associated with lower Mobility HRQoL (T-score - 0.9, [- 1.6 to - 0.2]; p = 0.01) and Cognitive Function HRQoL (T-score - 1.3 [- 2.0 to - 0.6]; p = 0.001) after correction for National Institutes of Health Stroke Scale score on admission, age, and time to follow-up.

CONCLUSIONS

Each additional day with a fever was predictive of worse HRQoL domains of Cognitive Function and Mobility after ICH up to 1 year. These data extend previous evidence on the negative association of fever and functional outcomes to the domains of Cognitive Function and Mobility HRQoL. HRQoL outcomes may be a sensitive and powerful way to measure the efficacy of fever control in future research.

Fever Burden in Patients With Subarachnoid Hemorrhage and the Increased Use of Antibiotics

BACKGROUND

Fever occurs in the majority of subarachnoid hemorrhage (SAH) patients. Nearly 50% of SAH patients have noninfectious fevers. Data are lacking describing the effects of fever burden in the SAH patient population.

METHODS

This was a single-center, retrospective observational cohort study in patients more or equal to 18 years of age with a diagnosis of nontraumatic SAH admitted to an ICU between January 1, 2010 and September 1, 2015. Exclusion criteria were SAH secondary to trauma or admission for more than 48 hours. Temperature measurements, demographic data, and other pertinent information were collected from Day 0 to Day 13. Daily fever burden was calculated for each patient by calculating an area under the curve.

RESULTS

A total of 194 subjects were included. The mean study period maximum temperature (Tmax) for all 194 patients was 40.8 ± 0.83°C. The mean overall fever burden for all 194 patients was 89.2 ± 99.59°C h more than 37°C. The overall fever burden peaked on day 5 and declined thereafter. Fever burden, Tmax, and length of stay in the hospital were all significantly associated with receipt of antibiotics. Only Tmax was associated with poor outcome. The 31 patients who had fever but no identified cause of infection received 1000 doses of antibiotics or 32.25 doses per patient.

CONCLUSION

Fever is common in SAH patients and is associated with antibiotic use, infection, vasospasm, and poor outcome. Some SAH patients may receive antibiotics unnecessarily for noninfectious fever. Clinicians should consider using site-specific parameters related to infection rather than systemic symptoms such as fever to evaluate infection in SAH patients.

Risk factors for postoperative meningitis after microsurgery for vestibular schwannoma

OBJECTIVE

Meningitis after microsurgery for vestibular schwannoma (VS) is a severe complication that results in high morbidity. However, few studies have focused on meningitis after VS surgery. The purpose of this study was to identify the risk factors for meningitis after VS surgery.

METHODS

We performed a retrospective analysis of all VS patients who underwent microsurgery and survived for at least 7 days after surgery, between 1 June 2015 and 30 November 2018 at West China Hospital of Sichuan University. Univariate and multivariate analyses were performed to identify the risk factors for postoperative meningitis (POM).

RESULTS

We enrolled 410 patients, 27 of whom had POM. Through univariate analysis, the factors of hydrocephalus (p = 0.018), Koos grade IV (p = 0.04), operative duration > 3 hours (p = 0.03) and intraoperative bleeding volume ≥400 ml (p = 0. 02) were significantly correlated with POM. The multivariate analysis showed that Koos grade IV (p = 0.04; OR = 3.19; 95% CI 1.032-3.190), operation duration > 3 hours (p = 0.03; OR = 7.927; 95% CI 1.043-60.265), and intraoperative bleeding volume ≥ 400 ml (p = 0.02; OR = 2.551; 95% CI 1.112-5.850) were the independent influencing factors of POM.

CONCLUSIONS

Koos grade IV, operation duration > 3 hours, and intraoperative blood loss ≥ 400 ml were identified as independent risk factors for POM after microsurgery for VS. POM also caused a prolonged hospital stay.

Aneurysmal subarachnoid hemorrhage: intensive care for improving neurological outcome

Background

Aneurysmal subarachnoid hemorrhage is a life-threatening disease requiring neurocritical care. Delayed cerebral ischemia is a well-known complication that contributes to unfavorable neurological outcomes. Cerebral vasospasm has been thought to be the main cause of delayed cerebral ischemia, and although several studies were able to decrease cerebral vasospasm, none showed improved neurological outcomes. Our target is not cerebral vasospasm but improving neurological outcomes. The purpose of this review is to discuss what intensivists should know and can do to improve clinical outcomes in subarachnoid hemorrhage patients.

Main body of the abstract

Delayed cerebral ischemia is thought to be due to not only vasospasm but also multifactorial mechanisms. Additionally, the concept of early brain injury, which occurs within the first 72 h after the hemorrhage, has become an important concern. Increasing sympathetic activity after the hemorrhage is associated with cardiopulmonary complications and poor outcomes. Serum lactate measurement may be a valuable marker reflecting the severity of sympathetic activity. The transpulmonary thermodilution method will bring about an advanced understanding of hemodynamic management. Fever is a well-recognized symptom and targeted temperature management is an anticipated intervention. To avoid hyperglycemia and hypoglycemia, performing moderate glucose control and minimizing glucose variability are important concepts in glycemic management, but the optimal target range remains unknown. Dysnatremia seems to be associated with negative outcomes. It is not clear yet that maintaining normonatremia actively improves neurological outcomes. Optimal duration of intensive care management has not been determined.

Short conclusion

Although we have an advanced understanding of the pathophysiology and clinical characteristics of subarachnoid hemorrhage, there are many controversies in the intensive care unit management of subarachnoid hemorrhage. With an awareness of not only delayed cerebral ischemia but also early brain injury, more attention should be given to various aspects to improve neurological outcomes.

Health Care-Associated Infections after Subarachnoid Hemorrhage

OBJECTIVE

Health care-associated infections (HAIs) after subarachnoid hemorrhage (SAH) are prevalent; however, data describing epidemiology of infection are limited. This study reports incidence rates, risk factors, and the resulting SAH patient-related outcomes.

METHODS

We studied the incidence of HAIs acquired in the intensive care unit (ICU) over a 6-year period. We used Bayesian Model Averaging to identify risk factors associated with an increased risk of HAIs, particularly urinary tract infections (UTI), pneumonia, and ventriculostomy-associated infections (VAI). We also examined the impact of HAIs on risk of vasospasm, ICU and hospital length of stay, and discharge disposition and adjusted for other risk factors.

RESULTS

Of 419 patients with SAH, 66 (15.8%) developed 79 HAI episodes. Mean HAI incidence rates (per 1000 ICU-days) were UTI, 7.1; pneumonia, 4.3; and VAI, 2.4. The admission characteristic associated with increased risk of overall HAI, UTI, and VAI was diabetes mellitus. Hunt and Hess grades III-V were associated with increased risk of overall HAI and VAI. Male gender, intraventricular hemorrhage, and blood glucose level (>10) were associated with increased risk of pneumonia, whereas the incidence was lower in the presence of steroids. HAI was associated with increased length of stay of 10 ICU-days and 22 hospital-days, but not vasospasm or poor discharge disposition.

CONCLUSIONS

HAIs are serious complications after SAH associated with prolonged ICU and hospital length of stay. Additional rigorous infection control measures aimed at patients with identifiable risk factors should trigger prevention, and early detection of nosocomial infections is warranted to further reduce the prevalence of HAIs.

Clinical and Laboratory Characteristics for the Diagnosis of Bacterial Ventriculitis After Aneurysmal Subarachnoid Hemorrhage

Background

The diagnosis of nosocomial bacterial ventriculitis in patients with subarachnoid hemorrhage (SAH) can be challenging.

Methods

We performed a retrospective study on the diagnostic accuracy of clinical and laboratory characteristics for the diagnosis of bacterial ventriculitis in 209 consecutive patients with an aneurysmal SAH admitted in a tertiary referral center from 2008 to 2010. Diagnostic value of clinical characteristics and inflammatory indexes in CSF and blood were determined for three diagnostic categories: (1) no suspicion for bacterial ventriculitis; (2) clinical suspicion for bacterial ventriculitis, defined as initiation of empirical antibiotic treatment for ventriculitis, but negative CSF cultures; and (3) CSF culture-positive bacterial ventriculitis.

Results

Empirical antibiotics for suspected ventriculitis was initiated in 48 of 209 (23 %) patients. CSF cultures were positive in 11 (5 %) patients. Within the group of suspected ventriculitis, only longer duration of CSF drainage and lower CSF red blood cell counts predicted for culture positivity. None of the other clinical features or inflammatory indexes in CSF and blood were associated with culture-proven bacterial ventriculitis.

Conclusions

Nosocomial bacterial ventriculitis in patients with aneurysmal SAH is often suspected but confirmed by culture in a minority of cases. Improvement of diagnostics for nosocomial bacterial ventriculitis in patients with aneurysmal SAH is needed.

Korean Clinical Practice Guidelines for Aneurysmal Subarachnoid Hemorrhage

Despite advancements in treating ruptured cerebral aneurysms, an aneurysmal subarachnoid hemorrhage (aSAH) is still a grave cerebrovascular disease associated with a high rate of morbidity and mortality. Based on the literature published to date, worldwide academic and governmental committees have developed clinical practice guidelines (CPGs) to propose standards for disease management in order to achieve the best treatment outcomes for aSAHs. In 2013, the Korean Society of Cerebrovascular Surgeons issued a Korean version of the CPGs for aSAHs. The group researched all articles and major foreign CPGs published in English until December 2015 using several search engines. Based on these articles, levels of evidence and grades of recommendations were determined by our society as well as by other related Quality Control Committees from neurointervention, neurology and rehabilitation medicine. The Korean version of the CPGs for aSAHs includes risk factors, diagnosis, initial management, medical and surgical management to prevent rebleeding, management of delayed cerebral ischemia and vasospasm, treatment of hydrocephalus, treatment of medical complications and early rehabilitation. The CPGs are not the absolute standard but are the present reference as the evidence is still incomplete, each environment of clinical practice is different, and there is a high probability of variation in the current recommendations. The CPGs will be useful in the fields of clinical practice and research.

Acute Cholecystitis as a Cause of Fever in Aneurysmal Subarachnoid Hemorrhage

Background

Fever is a very common complication that has been related to poor outcomes after aneurysmal subarachnoid hemorrhage (aSAH). The incidence of acalculous cholecystitis is reportedly 0.5%–5% in critically ill patients, and cerebrovascular disease is a risk factor for acute cholecystitis (AC). However, abdominal evaluations are not typically performed for febrile patients who have recently undergone aSAH surgeries. In this study, we discuss our experiences with febrile aSAH patients who were eventually diagnosed with AC.

Methods

We retrospectively reviewed 192 consecutive patients who underwent aSAH from January 2009 to December 2012. We evaluated their characteristics, vital signs, laboratory findings, radiologic images, and pathological data from hospitalization. We defined fever as a body temperature of >38.3°C, according to the Society of Critical Care Medicine guidelines. We categorized the causes of fever and compared them between patients with and without AC.

Results

Of the 192 enrolled patients, two had a history of cholecystectomy, and eight (4.2%) were eventually diagnosed with AC. Among them, six patients had undergone laparoscopic cholecystectomy. In their pathological findings, two patients showed findings consistent with coexistent chronic cholecystitis, and two showed necrotic changes to the gall bladder. Patients with AC tended to have higher white blood cell counts, aspartame aminotransferase levels, and C-reactive protein levels than patients with fevers from other causes. Predictors of AC in the aSAH group were diabetes mellitus (odds ratio [OR], 8.758; P = 0.033) and the initial consecutive fasting time (OR, 1.325; P = 0.024).

Conclusions

AC may cause fever in patients with aSAH. When patients with aSAH have a fever, diabetes mellitus and a long fasting time, AC should be suspected. A high degree of suspicion and a thorough abdominal examination of febrile aSAH patients allow for prompt diagnosis and treatment of this condition. Additionally, physicians should attempt to decrease the fasting time in aSAH patients.

Normothermia and Stroke

OPINION STATEMENT

In the past two decades, there has been much focus on the adverse effect of fever on neurologic outcome, the benefits of hypothermia on functional outcomes, and the interplay of associated complications. Despite decades of experience regarding randomized, safety and feasibility, case-controlled, retrospective studies, there has yet to be a large, randomized, multicenter, clinical trial with the appropriate power to address the potential benefits of targeted temperature modulation compared to hypothermia alone. What remains unanswered is the appropriate timing of initiation, duration, rewarming speed, and depth of targeted temperature management. We learn from the cardiac arrest literature that there is a neuroprotective value to hypothermia and, most recently, near normothermia (36 °C) as well. We have also established that increased depths of cooling are associated with increases in shivering, which warrant more aggressive pharmacologic management. Normothermia also has the advantage of allowing for more rapid clearance of sedating medications and less confounding of neuroprognostication. More difficult to quantify is the increased nursing and patient care complexity associated with moderate hypothermia compared to normothermia. It remains crucial, for those patients who are being considered for hypothermia/normothermia, to be cared for in an experienced ICU, driven under protocol, with aggressive shivering management and an expectation and acceptance of the complications associated with targeted temperature management. If targeted temperature management is not of consideration, then aggressive fever control should be undertaken pharmacologically and non-invasively, as they have been shown to be safe.

Temperature Management in the Neurointensive Care Unit

OPINION STATEMENT

Fever in the neurocritical care unit has a high prevalence and is associated with worse outcomes in patients with severe neurologic illness. While it is well accepted that fever is associated with worse outcomes in this patient population, it is unclear if aggressive temperature management will improve outcomes. Temperature should be monitored routinely in this high-risk population, fever worked up appropriately to identify infectious etiology, and reasonable measures taken to control elevated temperature. While infection is a common source of fever in patients with significant neurologic illness, the fever may also be exacerbated by the underlying brain injury. The clinician must decide at which point to initiate fever control measures, how aggressively to manage the fever, and which temperature to target for normothermia. Several pharmacological agents are available as first-line therapy. Depending on the degree and severity of the febrile response, advanced temperature-control devices should be added to pharmacological measures. Several types of temperature-control devices are available, including invasive (intravascular catheters) and noninvasive (external cooling pads) technologies. The clinician should utilize both pharmacologic and device-based temperature therapies to minimize the amount of time spent in a febrile state and help to mitigate the secondary brain injury brought on by fever.

Transfer time to a high-volume center for patients with subarachnoid hemorrhage does not affect outcomes

OBJECTIVES

The objective of our study was to examine patients with aneurysmal subarachnoid hemorrhage transferred and directly admitted to our institution in order to determine how transfer time affects outcomes.

METHODS

A retrospective cohort study was performed of all patients undergoing treatment for aneurysmal subarachnoid hemorrhage between 2005 and 2012 at the University of Michigan. Variables, including transfer time, were tested for their independent association with the primary outcomes of symptomatic vasospasm and 12-month outcome as well as secondary outcomes of aneurysm rebleeding and 12-month mortality.

RESULTS

During the study period, 263 (87.4%) patients were transferred to our institution and 38 (12.6%) were directly admitted for treatment of aneurysmal subarachnoid hemorrhage. Transfer time was not associated with the occurrence of symptomatic vasospasm, 12-month outcome, rebleeding, or 12-month mortality. Higher Hunt-Hess grade was associated with the occurrence of symptomatic vasospasm as well as with poorer 12-month outcome.

CONCLUSIONS

Transfer time was not associated with the occurrence of symptomatic vasospasm, 12-month outcome, rebleeding, or 12-month mortality. We believe our data argue that protocols should emphasize early resuscitation and stabilization followed by safe transfer rather than a hyperacute transfer paradigm. However, transfer time should be minimized as much as possible so as not to delay time to definitive treatment.

Fever burden is an independent predictor for prognosis of traumatic brain injury

OBJECTIVE

To evaluate fever burden as an independent predictor for prognosis of traumatic brain injury (TBI).

METHODS

This retrospective study involved 355 TBI patients with Glasgow Coma Scale (GCS) ≤14, who presented at the emergency department of our hospital between November 2010 and October 2012. At 6 months follow-up, patients were divided into 5 groups based on Glasgow Outcome Scale (GOS) and dichotomized to GOS score (high (4 to 5) vs. low (1 to 3)). The relationship between fever burden and GOS was assessed.

RESULTS

Fever burden increased as GOS scores decreased from 5 to 2, except for score 1 of GOS, which corresponded to a significant lower fever burden. Following dichotomization, patients in the high GOS group were younger, and showed less abnormal pupil reactivity (P<0.001), a higher median GCS score (P<0.001), and a lower median fever burden (P<0.001), compared with patients in the low GOS group. Univariate logistic regression analysis revealed that poor TBI prognosis was related to age, GCS, pupil reactivity, and fever burden (OR: 1.166 [95% CI: 1.117-1.217] P<0.0001). Multivariate logistic regression analysis identified fever burden as an independent predictor of poor prognosis after TBI (OR 1.098; 95% CI: 1.031-1.169; P = 0.003). These observations were confirmed by evaluation of the receiver operating characteristic (ROC) curve for fever burden (area under the curve [AUC] 0.73 [95% CI: 0.663-0.760]).

CONCLUSION

Fever burden might be an independent predictor for prognosis of TBI. High fever burden in the early stage of the disease course associated with TBI could increase the risk of poor prognosis.

Management of Fever, Hyperglycemia, and Swallowing Dysfunction following Hospital Admission for Acute Stroke in New South Wales, Australia

Background

Fever, hyperglycemia, and swallow dysfunction poststroke are associated with significantly worse outcomes. We report treatment and monitoring practices for these three items from a cohort of acute stroke patients prior to randomization in the Quality in Acute Stroke Care trial.

Method

Retrospective medical record audits were undertaken for prospective patients from 19 stroke units. For the first three-days following stroke, we recorded all temperature readings and administration of paracetamol for fever (≥37.5°C) and all glucose readings and administration of insulin for hyperglycemia (>11 mmol/L). We also recorded swallow screening and assessment during the first 24 h of admission.

Results

Data for 718 (98%) patients were available; 138 (19%) had four hourly or more temperature readings and 204 patients (29%) had a fever, with 44 (22%) receiving paracetamol. A quarter of patients ( n = 102/412, 25%) had six hourly or more glucose readings and 23% (95/412) had hyperglycemia, with 31% (29/95) of these treated with insulin. The majority of patients received a swallow assessment ( n = 562, 78%) by a speech pathologist in the first instance rather than a swallow screen by a nonspeech pathologist ( n = 156, 22%). Of those who passed a screen ( n = 108 of 156, 69%), 68% ( n = 73) were reassessed by a speech pathologist and 97% ( n = 71) were reconfirmed to be able to swallow safely.

Conclusions

Our results showed that acute stroke patients were: undermonitored and undertreated for fever and hyperglycemia; and underscreened for swallowing dysfunction and unnecessarily reassessed by a speech pathologist, indicating the need for urgent behavior change.

Relationship between temperature, hematoma growth, and functional outcome after intracerebral hemorrhage

BACKGROUND

Fever and hematoma growth are known to be independent predictors of poor outcome after intracerebral hemorrhage (ICH). We sought to assess the distribution of temperature at different stages in relation to hematoma growth and functional outcome at 90 days in a cohort of ICH patients.

METHODS

Data of patients registered in the Virtual International Stroke Trials Archive--ICH were analyzed. Temperatures at baseline, 24, 48, 72, and 168 h were assessed in relation to the hematoma growth and functional outcome at 90 days. We calculated the daily linear variation of each subject's temperature by subtracting 37 °C from the maximal daily recorded temperature (delta-temperature). We used logistic regression and mixed-effects models to identify factors associated with hematoma growth, poor outcome, and temperature elevation after ICH.

RESULTS

303 patients were included in the analysis. The average age was 66 ± 12 years, 200 (66 %) were males, median admission NIHSS was 13 [Interquartile range (IQR), 9-18), median GCS was 15 (IQR, 14-15). Hematoma growth occurred in 22 % and poor functional outcome at 90-days occurred in 41 % of the patients. Cumulative delta-temperature at 72 h was associated with hematoma growth; age, ICH score, hematoma growth, and cumulative delta-temperature at 168 h were associated with poor outcome at 90 days. Factors associated with fever in mixed-models were day after onset of ICH, hypertension, base hematoma volume, intraventricular-hemorrhage, pneumonia, and hematoma growth.

CONCLUSIONS

There is a temporal and independent association between fever and hematoma growth. Fever after ICH is associated with poor outcome at 90 days. Future research is needed to study the mechanisms of this phenomenon and if early protocols of temperature modulation would be associated with improved outcomes after ICH.

Managing subarachnoid hemorrhage in the neurocritical care unit

Patients with aneurysmal subarachnoid hemorrhage who survive the initial hemorrhage require complex interventions to occlude the aneurysm, typically followed by a prolonged intensive care unit and hospital course to manage the complications that follow. Much of the morbidity and mortality from this disease happens in delayed fashion in the neurocritical care unit. Despite progress made in the last decades, much remains to be understood about this disease and how to best manage these patients. This article provides a review of current evidence and the authors' experience, aimed at providing practical aid to those caring for patients with this disease.

Update on the management of subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease. Outcome after SAH is mainly determined by the initial severity of the hemorrhage. Neuroimaging, in particular computed tomography, and aneurysm repair techniques, such as coiling and clipping, as well as neurocritical care management, have improved during the last few years. The management of a patient with SAH should have an interdisciplinary approach with case discussions between the neurointensivist, interventionalist and the neurosurgeon. The patient should be treated in a specialized neurointensive care unit of a center with sufficient SAH case volume. Poor-grade patients can be observed for complications and delayed cerebral ischemia through continuous monitoring techniques in addition to transcranial Doppler ultrasonography such as continuous electroencephalography, brain tissue oxygenation, cerebral metabolism, cerebral blood flow and serial vascular imaging. Neurocritical care should focus on neuromonitoring for delayed cerebral ischemia, management of hydrocephalus, seizures and intracranial hypertension, as well as of medical complications such as hyperglycemia, fever and anemia.

Subarachnoid Extension of Primary Intracerebral Hemorrhage is Associated With Poor Outcomes

Background and Purpose—

Extension of hemorrhage into the subarachnoid space is observed in primary intracerebral hemorrhage (ICH), yet the phenomenon has undergone limited study and is of unknown significance. The objective of this study is to evaluate the incidence, characteristics, and clinical consequences of subarachnoid hemorrhage extension (SAHE) in ICH on functional outcomes.

Methods—

Patients with primary ICH were enrolled into a prospective registry between December 2006 and June 2012. Patients were managed and serial neuroimaging was obtained per a structured protocol. Presence of any subarachnoid blood on imaging was identified as SAHE by expert reviewers blinded to outcomes. Regression models were developed to test whether the occurrence of SAHE was an independent predictor of functional outcomes as measured with the modified Rankin Scale.

Results—

Of 234 patients with ICH, 93 (39.7%) had SAHE. Interrater agreement for SAHE was excellent (kappa=0.991). SAHE was associated with lobar hemorrhage location (65% of SAHE vs 19% of non-SAHE cases; P <0.001) and larger hematoma volumes (median 23.8 vs 6.7; P <0.001). Fever (69.9% vs 51.1%; P =0.005) and seizures (8.6% vs 2.8%; P =0.07) were more common in patients with SAHE. SAHE was a predictor of death by day 14 (odds ratio, 4.45; 95% confidence interval, 1.88–10.53; P =0.001) and of higher (worse) modified Rankin Scale scores at 28 days (odds ratio, 1.76 per mRS point; 95% confidence interval, 1.01–3.05; P =0.012) after adjustment for ICH score.

Conclusions—

SAHE is associated with worse modified Rankin Scale independent of traditional ICH severity measures. Underlying mechanisms and potential treatments of SAHE require further study.

Predictors of shunt-dependent chronic hydrocephalus after aneurysmal subarachnoid haemorrhage

INTRODUCTION

Chronic hydrocephalus is a common complication that can occur after aneurysmal subarachnoid haemorrhage (SAH). The purpose of this study was to investigate clinical risk factors that could predict the occurrence of shunt-dependent chronic hydrocephalus after aneurysmal SAH.

METHODS

Eighty-eight consecutive patients who underwent either surgery or transarterial endovascular embolization as a treatment for cerebral aneurysm within 72 h -after experiencing SAH from March 2005 to July 2006 were studied retrospectively to assess the risk factors that might predict shunt-dependent chronic hydrocephalus. Clinical and demographic factors were examined, including age, sex, initial admission mean arterial blood pressure (MABP), blood sugar level at admission, fever frequency, initial external ventricular drainage (EVD), Fisher grade, Hunt and Hess grade, intraventricular haemorrhage (IVH) and treatment methods to define predictors of shunt-dependent hydrocephalus. The length of hospital stay and modified Rankin scale recorded 6 months after SAH were also evaluated; these parameters were compared between the shunt-dependent and non-shunt-dependent groups.

RESULTS

Of the 88 patients, 22 (25%) underwent shunt placement to treat their chronic hydrocephalus. The average length of hospital stay was 33.9 days for the shunt-treated group and 14 days for the non-shunt-treated group. The non-shunt-treated group scored an average of 1.05 on the modified Rankin scale compared with 2.77 for the shunt-treated group. A univariate analysis revealed that several admission variables were associated with long-term shunt-dependent hydrocephalus: (1) increased age (p = 0.023); (2) initial admission MABP (p = 0.027); (3) a high Fisher grade (p = 0.031); (4) a poor admission Hunt and Hess grade (p = 0.030); (5) the presence of IVH (p = 0.029), and (6) initial EVD (p < 0.0001). The factor most commonly associated with shunt-dependent hydrocephalus over the course of hospital days was fever frequency (p < 0.0001).

CONCLUSIONS

Chronic hydrocephalus after aneurysmal SAH has a multifactorial aetiology. Understanding the risk factors that predict the occurrence of chronic hydrocephalus may help neurosurgeons to expedite permanent cerebrospinal fluid diversion, which could decrease both the cost and length of hospital stay and prevent further complications.

Brain temperature: physiology and pathophysiology after brain injury

The regulation of brain temperature is largely dependent on the metabolic activity of brain tissue and remains complex. In intensive care clinical practice, the continuous monitoring of core temperature in patients with brain injury is currently highly recommended. After major brain injury, brain temperature is often higher than and can vary independently of systemic temperature. It has been shown that in cases of brain injury, the brain is extremely sensitive and vulnerable to small variations in temperature. The prevention of fever has been proposed as a therapeutic tool to limit neuronal injury. However, temperature control after traumatic brain injury, subarachnoid hemorrhage, or stroke can be challenging. Furthermore, fever may also have beneficial effects, especially in cases involving infections. While therapeutic hypothermia has shown beneficial effects in animal models, its use is still debated in clinical practice. This paper aims to describe the physiology and pathophysiology of changes in brain temperature after brain injury and to study the effects of controlling brain temperature after such injury.

The effect of decompressive hemicraniectomy on brain temperature after severe brain injury

BACKGROUND

Animal studies have shown that even a small temperature elevation of 1°C can cause detrimental effects after brain injury. Since the skull acts as a potential thermal insulator, we hypothesized that decompressive hemicraniectomy facilitates surface cooling and lowers brain temperature.

METHODS

Forty-eight patients with severe brain injury (TBI = 38, ICH = 10) with continuous brain temperature monitoring were retrospectively studied and grouped into "hemicraniectomy" (n = 20) or "no hemicraniectomy" (n = 28) group. The paired measurements of core body (T Core) and brain (T Br) temperature were recorded at 1-min intervals over 12 ± 7 days. As a surrogate measure for the extent of surface heat loss from the brain, ∆T Core-Br was calculated as the difference between T Core and T Br with each recording. In order to accommodate within-patient temperature correlations, mixed-model regression was used to assess the differences in ∆T Core-Br between those with and without hemicraniectomy, adjusted for core body temperature and diagnosis.

RESULTS

A total of 295,883 temperature data pairs were collected (median [IQR] per patient: 5047 [3125-8457]). Baseline characteristics were similar for age, sex, diagnosis, incidence of sepsis, Glasgow Coma Scale score, ICU mortality, and ICU length of stay between the two groups. The mean difference in ∆T Core-Br was 1.29 ± 0.87°C for patients with and 0.80 ± 0.86°C for patients without hemicraniectomy (P < 0.0001). In mixed-model regression, accounting for temperature correlations within patients, hemicraniectomy and higher T Core were associated with greater ∆T Core-Br (hemicraniectomy: estimated effect = 0.60, P = 0.003; T Core: estimated effect = 0.21, P < 0.0001).

CONCLUSIONS

Hemicraniectomy is associated with modestly but significantly lower brain temperature relative to core body temperature.

Fever management in SAH

An electronic literature search through August 2010 was performed to obtain articles describing fever incidence, impact, and treatment in patients with subarachnoid hemorrhage. A total of 24 original research studies evaluating fever in SAH were identified, with studies evaluating fever and outcome, temperature control strategies, and shivering. Fever during acute hospitalization for subarachnoid hemorrhage was consistently linked with worsened outcome and increased mortality. Antipyretic medications, surface cooling, and intravascular cooling may all reduce temperatures in patients with subarachnoid hemorrhage; however, benefits from cooling may be offset by negative consequences from shivering.

Effect of rebleeding on the course and incidence of vasospasm after subarachnoid hemorrhage

OBJECTIVE

Rebleeding of an aneurysm is a leading cause of morbidity and mortality after subarachnoid hemorrhage (SAH). Whereas numerous studies have demonstrated the risk factors associated with rebleeding, few data on complications of rebleeding, including its effect on the development of delayed cerebral ischemia (DCI), are available.

METHODS

A nested case-control study was performed on patients with rebleeding and control subjects matched for modified Fisher scale, Hunt-Hess grade, age, and sex previously entered into a prospective database. Rebleeding was defined as new hemorrhage apparent on repeat CT with or without new symptoms. Incidence and time course of DCI and hospital complications were compared. A secondary analysis of DCI and hospital complications was also performed on subjects surviving to postbleed day 7.

RESULTS

We identified 120 patients with rebleeding and 359 control subjects from 1996 to 2011. The rebleeding rate was 8.6%. In both the primary and secondary analyses, there was no difference in the incidence of DCI or its time course (29% vs. 27%, p = 0.6; 7 ± 5 vs. 7 ± 6 days, p = 0.9 for primary analysis; 39% vs. 31%, p = 0.1, 7 ± 5 vs. 7 ± 6 days, p = 0.6 for the secondary analysis). In a multivariate logistic regression model, rebleeding was associated with the complications of hyponatremia, respiratory failure, and hydrocephalus. Patients with rebleeding had higher rates of mortality, brain death, and poor outcomes.

CONCLUSIONS

Rebleeding after SAH is associated with multiple medical and neurologic complications, resulting in higher morbidity and mortality, but is not associated with change of incidence or timing of DCI.

Epidemiology and outcomes of fever burden among patients with acute ischemic stroke

BACKGROUND AND PURPOSE

Although fever following ischemic stroke is common and has been associated with poor patient outcomes, little is known about which aspects of fever (eg, frequency, severity, or duration) are most associated with outcomes.

METHODS

We used data from a retrospective cohort of acute ischemic stroke patients who were admitted to 1 of 5 hospitals (1998-2003). A fever event was defined as a period with a temperature≥100.0 °F (37.8 °C). Fever burden was defined as the maximum temperature (Tmax) minus 100.0 °F, multiplied by the number of days with a fever. Fever burden (in degree-days) was categorized as low (0.1-2.0), medium (2.1-4.0), or high (≥4.0). Logistic regression was used to evaluate the adjusted association of any fever episode and fever burden with the combined outcome of in-hospital mortality or discharge to hospice.

RESULTS

Among 1361 stroke patients, 483 patients (35.5%) had ≥1 fever event. Among febrile patients, the median Tmax was 100.9 °F (range, 100.0-106.6 °F), 87% had ≤2 events and median total fever days was 2. Patients with any fever event had higher combined outcome rates after adjusting for demographics, stroke severity, and clinical characteristics: adjusted odds ratio (aOR), 2.7 (95% CI, 1.6-4.4). Higher fever burden was also associated with the combined outcome: high burden aOR, 6.7 (95% CI, 3.6-12.7); medium burden aOR, 3.9 (95% CI, 1.9-8.2); and low burden aOR, 1.2 (95%CI, 0.6-2.3) versus no fever.

CONCLUSIONS

This study confirms that poststroke fever occurs commonly and demonstrates that patients with high fever burden have a 6-fold increased odds of death or discharge to hospice.

Impact of systemic inflammatory response syndrome on vasospasm, cerebral infarction, and outcome after subarachnoid hemorrhage: exploratory analysis of CONSCIOUS-1 database

BACKGROUND

Systemic inflammatory response syndrome (SIRS) may develop after aneurysmal subarachnoid hemorrhage (SAH). We investigated factors associated with SIRS after SAH, whether SIRS was associated with complications of SAH such as vasospasm, cerebral infarction, and clinical outcome, and whether SIRS could contribute to a difference in outcome between patients treated by endovascular coiling or neurosurgical clipping of the ruptured aneurysm.

METHODS

This was exploratory analysis of 413 patients in the CONSCIOUS-1 study. SIRS was diagnosed if the patient had at least 2 of 4 variables (hypothermia/fever, tachycardia, tachypnea, and leukocytosis/leukopenia) within 4 days of admission. Clinical outcome was measured on the Glasgow outcome scale 3 months after SAH. The relationship between clinical and radiologic variables and SIRS, angiographic vasospasm, delayed ischemic neurologic deficit (DIND), cerebral infarction, vasospasm-related infarction, and clinical outcome were modeled with uni- and multivariable analyses.

RESULTS

63% of patients developed SIRS. Many factors were associated with SIRS in univariate analysis, but only poor WFNS grade and pneumonia were independently associated with SIRS in multivariable analysis. SIRS burden (number of SIRS variables per day over the first 4 days) was associated with poor outcome, but not with angiographic vasospasm, DIND, or cerebral infarction. The method of aneurysm treatment was not associated with SIRS.

CONCLUSION

SIRS was associated with poor outcome but not angiographic vasospasm, DIND, or cerebral infarction after SAH in the CONSCIOUS-1 data. There was no support for the notion that neurosurgical clipping is associated with a greater risk of SIRS than endovascular coiling.

Current and future treatment considerations in the management of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a type of hemorrhagic stroke that can cause significant morbidity and mortality. Although guidelines have been published to help direct the care of these patients, there is insufficient quality literature regarding the medical and pharmacological management of patients with aSAH. Treatment is divided into 3 categories: supportive therapy, prevention of complications, and treatment of complications. There are numerous pharmacological therapies that are targeted at prevention and treatment of the neurological and medical complications that may arise. Rebleeding, hydrocephalus, cerebral vasospasm, and seizures are the most common neurological complications while the most common medical complications include hyponatremia, pulmonary edema, cardiac arrhythmias, neurogenic stunned myocardium, fever, anemia, infection, hyperglycemia, and venous thromboembolism. Risk factors, clinical presentation, diagnosis, pathophysiology, as well as initial management, prevention, and treatment of complications will be the focus of this discussion.