Severe heat stroke with multiorgan failure following collapse in a sauna

Heat stroke is characterised by hyperthermia and acute encephalopathy. We describe a rare case of classical heat stroke secondary to prolonged sauna use with multiorgan sequelae including seizures, liver injury, kidney injury, disseminated intravascular coagulation, rhabdomyolysis and type 2 myocardial infarction. The patient was treated with external cooling, intravenous fluid therapy and blood products, and made a full recovery without need for advanced organ support. We discuss the evidence base surrounding the immediate treatment of heat stroke in the emergency department.

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.

Factors associated with fever after cardiac arrest: A post-hoc analysis of the FINNRESUSCI study

BACKGROUND

Fever after cardiac arrest may impact outcome. We aimed to assess the incidence of fever in post-cardiac arrest patients, factors predicting fever and its association with functional outcome in patients treated without targeted temperature management (TTM).

METHODS

The FINNRESUSCI observational cohort study in 2010-2011 included intensive care unit (ICU)-treated out-of-hospital cardiac arrest (OHCA) patients from all five Finnish university hospitals and 14 of 15 central hospitals. This post hoc analysis included those FINNRESUSCI study patients who were not treated with TH. We defined fever as at least one temperature measurement of ≥37.8°C within 72 h of ICU admission. The primary outcome was favourable functional outcome at 12 months, defined as cerebral performance category (CPC) of 1 or 2. Binary logistic regression models including witnessed arrest, bystander cardiopulmonary resuscitation (CPR), initial rhythm and delay of return of spontaneous circulation were used to compare the functional outcomes of the groups.

RESULTS

There were 67,428 temperature measurements from 192 patients, of whom 89 (46%) experienced fever. Twelve-month CPC was missing in 7 patients, and 51 (28%) patients had favourable functional outcome at 12 months. The patients with shockable initial rhythms had a lower incidence of fever within 72 h of ICU admission (28% vs. 72%, p < .01), and the patients who experienced fever had a longer median return of spontaneous circulation (ROSC) delay (20 [IQR 10-30] vs. 14 [IQR 9-22] min, p < .01). Only initial non-shockable rhythm (OR 2.99, 95% CI 1.51-5.94) was associated with increased risk of fever within the first 72 h of ICU admission. Neither time in minutes nor area (minutes  ×  degree celsius over threshold) over 37°C, 37.5°C, 38°C, 38.5°C, 39°C, 39.5°C or 40°C were significantly different in those with favourable functional outcome compared to those with unfavourable functional outcome within the first 24, 48 or 72 h from ICU admission. Fever was not associated with favourable functional outcome at 12 months (OR 0.90, 95% CI 0.44-1.84).

CONCLUSIONS

Half of OHCA patients not treated with TTM developed fever. We found no association between fever and outcome.

The impact of fever as a testing indication on the detection rate of deep vein thrombosis in neurocritically ill patients

Aim

Deep vein thrombosis (DVT) is considered a possible source of non-infectious, non-central fever in the intensive care unit (ICU). In the neurocritically ill, it is unknown whether lower extremity venous Doppler ultrasonography (LEVDUS) for DVT in the setting of fever leads to a higher detection rate than the baseline detection rate of DVT in this population. The aim of this study was to compare the DVT detection rate of LEVDUS performed for the indication of fever to LEVDUS performed for other indications in a neurosciences ICU.

Methods

Requisition forms for all LEVDUS performed in a referral neurosciences ICU were reviewed and separated into those with "fever" as the stated reason for request and those with other stated reasons. The DVT detection rate was compared between these two categories of indications.

Results

Five hundred eleven LEVDUS were analyzed, of which 422 had been ordered for indications other than fever. Sixteen of these tests were positive, a detection rate of 3.8%. The remaining 89 LEVDUS had "fever" as the ordering indication. Six of these tests were positive for DVT, a detection rate of 6.7%. The likelihood of positivity of a test obtained as part of fever evaluation relative to one obtained for non-fever indications was not significantly different (OR, 1.83; 95% CI, 0.570-5.11; P = 0.246).

Conclusion

LEVDUS triggered by fever detected DVT at a numerically, but not statistically significantly higher rate than did LEVDUS performed for other indications in a neurocritically ill population. More rigorous investigation of this question is needed.

Post-craniotomy fever and its associated factors in patients with traumatic brain injury

BACKGROUND

Fever frequently occurs in patients with traumatic brain injury and can cause secondary damage to the brain. Critical care nurses play essential roles in assessing and managing fever in these patients.

AIM

The study aimed to (a) examine the fever causes in and condition of neurosurgical patients with traumatic brain injury in intensive care, (b) identify the factors associated with fever, and (c) determine the effects of fever on hospital stay and prognosis.

STUDY DESIGN

This study is a retrospective observational design.

METHODS

Data were collected through chart reviews of 93 traumatic brain injury patients admitted to a teaching hospital's intensive care unit for postoperative care. Fever was defined as at least one episode of body temperature >38°C.

RESULTS

Of the 93 patients, 76 developed a fever within 1-week post-craniotomy. Of these, 49 were infection-related and 27 were unexplained. Results of logistic regression showed that the preoperative Glasgow coma scale score (ß = -.323; P = .013) and length of intubation (ß = .480; P = .005) were the key predictors of unexplained post-craniotomy fever, and these two variables (ß = -.494; P < .001 and ß = .479; P = .006, respectively) were also the key predictors of infection-related fever.

CONCLUSION

A significant portion of patients developed a fever during the first post-craniotomy week. Patients with a lower pre-craniotomy Glasgow coma scale score and a longer intubation length were at a greater risk for both infection-related fever and unexplained fever. Patients with fever had a bad outcome score.

RELEVANCE TO CLINICAL PRACTICE

Critical care nurses should closely monitor traumatic brain injury patients' body temperatures and employ evidence-based infection prevention and control measures to minimize their infection risks. Respiratory care and intensive care unit Liberation Bundle should be reinforced to liberate these patients from mechanical ventilation and its associated complications.

Management of Acute Ischemic Stroke

Objectives:

Concise “synthetic” review of the state of the art of management of acute ischemic stroke.

Data Sources:

Available literature on PubMed.

Study Selection:

We selected landmark studies, recent clinical trials, observational studies, and professional guidelines on the management of stroke including the last 10 years.

Data Extraction:

Eligible studies were identified and results leading to guideline recommendations were summarized.

Data Synthesis:

Stroke mortality has been declining over the past 6 decades, and as a result, stroke has fallen from the second to the fifth leading cause of death in the United States. This trend may follow recent advances in the management of stroke, which highlight the importance of early recognition and early revascularization. Recent studies have shown that early recognition, emergency interventional treatment of acute ischemic stroke, and treatment in dedicated stroke centers can significantly reduce stroke-related morbidity and mortality. However, stroke remains the second leading cause of death worldwide and the number one cause for acquired long-term disability, resulting in a global annual economic burden.

Conclusions:

Appropriate treatment of ischemic stroke is essential in the reduction of mortality and morbidity. Management of stroke involves a multidisciplinary approach that starts and extends beyond hospital admission.

Evaluation of Evidence-Based Guidelines for Fever Management in Critically Ill Adult Patients With Brain Injury

PURPOSE

The aim of this study was to evaluate the effectiveness of evidence-based guidelines for fever management of critically ill adult patients with brain injury.

METHODS

We used a pretest-posttest design with 48 patients 19 years or older admitted to an intensive care unit after surgery for brain injury. We applied evidence-based guidelines only to an experimental group of 24 patients and compared with 24 control patients who did not receive evidence-based guidelines. Experimental and control groups were matched 1:1 using the Acute Physiology and Chronic Health Evaluation II score. Data included the proportion of patients with reduced fever and time to normalized temperature.

RESULTS

The proportion of patients whose temperature fell to normal after fever was 4.5 times higher in the experimental group than in the control group. The time it took the patients' highest fever to fall to normal during their intensive care unit stay was 4.84 times faster in the experimental group than in the control group (hazard ratio, 4.84; 95% confidence interval, 1.79-13.11; P = .002).

CONCLUSION

Evidence-based guidelines for fever management in patients with a brain injury can be used in nursing practice with rapid response, improving healthcare efficiency and contributing to better outcomes for critically ill patients.

Association of body temperature with in-hospital mortality among paediatric trauma patients: an analysis of a nationwide observational trauma database in Japan

OBJECTIVES

To examine the association between body temperature (BT) on hospital arrival and in-hospital mortality among paediatric trauma patients.

DESIGN

A retrospective cohort study.

SETTING

Japan Trauma Data Bank (JTDB, which is a nationwide, prospective, observational trauma registry with data from 235 hospitals).

PARTICIPANTS

Paediatric trauma patients <16 years old who were transferred directly from the scene of injury to the hospital and registered in the JTDB from January 2004 to December 2017 were included. We excluded patients >16 years old and those who developed cardiac arrest before or on hospital arrival.

PRIMARY OUTCOME

The association between BT on hospital arrival and in-hospital mortality. We conducted multivariate logistic regression analyses to calculate the adjusted ORs, with their 95% CIs, of the association between BT and in-hospital mortality.

RESULTS

A total of 9012 patients were included (median age: 9 years (IQR, 6.0-13.0 years), mortality: 2.5% (mortality number was 226 in total 9012 patients)). In the multivariate logistic regression analysis, the corresponding adjusted ORs of BT <36.0°C and BT ≥37.0°C, relative to a BT of 36°C-36.9°C, for in-hospital mortality were 2.83 (95% CI: 1.85 to 4.33) and 0.93 (95% CI: 0.53 to 1.63), respectively.

CONCLUSIONS

In paediatric patients with hypothermia (BT <36.0°C) on hospital arrival, a clear association with in-hospital mortality was observed; no such association was observed between higher BT values (≥37.0°C) and outcomes.

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.

Body temperature and in-hospital mortality in trauma patients: analysis of a nationwide trauma database in Japan

PURPOSE

Avoiding body temperature (BT) abnormalities has been emphasized in trauma care, and BT correction in the initial treatment period may improve patient outcome. However, the effect of hyperthermia at hospital arrival on mortality in trauma patients is unclear. This study aimed to identify the association between BT and in-hospital mortality among adult trauma patients.

METHODS

This was a retrospective analysis of a multi-centre prospective cohort study. Data were obtained from the Japan Trauma Data Bank (JTDB). Adult trauma patients who were transferred directly from the scene of injury to the hospital and registered in the JTDB between January 2004 and December 2017 were included. The primary outcome was the association between BT at hospital arrival and in-hospital mortality. BT at hospital arrival was classified by 1 °C strata. We conducted multivariable logistic regression analyses to calculate the adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for in-hospital mortality for each BT group using 36.0-36.9 °C as a reference.

RESULTS

Overall, 153,117 patients were included. The total mortality rate was 7% (n = 10,118). The adjusted OR for in-hospital mortality for < 35.0 °C was 1.65 (95% CI 1.51-1.79, p < 0.001), 35.0-35.9 °C was 1.33 (95% CI 1.25-1.41, p < 0.001), 37.0-37.9 °C was 0.99 (95% CI 0.91-1.07, p = 0.639), 38.0-38.9 °C was 1.30 (95% CI 1.08-1.56, p = 0.007) and > 39.0 °C was 1.62 (95% CI 1.18-2.22, p = 0.003) compared to that for normothermia.

CONCLUSIONS

Our results reveal that hypothermia and hyperthermia at hospital arrival are associated with increased in-hospital mortality in adult trauma patients.

Protocolized Brain Oxygen Optimization in Subarachnoid Hemorrhage

BACKGROUND

Brain tissue hypoxia (P_btO₂ < 20 mmHg) is common after subarachnoid hemorrhage (SAH) and associated with poor outcome. Recent data suggest that brain oxygen optimization is feasible and reduces the time spent with P_btO₂ < 20 mmHg from 45 to 16% in patients with severe traumatic brain injury. Here, we intended to quantify the brain tissue hypoxia burden despite implementation of a protocolized treatment approach in poor-grade SAH patients and to identify the simultaneous occurrence of pathologic values potentially amenable to treatment.

METHODS

We present a bi-centric observational cohort study including 100 poor-grade SAH patients admitted to two tertiary care centers who underwent multimodal brain monitoring and were managed with a P_btO₂-targeted protocolized approach. P_btO₂ optimization (≥ 20 mmHg) included a stepwise neuro-intensive care approach, aiming to prevent low cerebral perfusion pressure (CPP), and blood hemoglobin, and to keep normocapnia, normoxemia, and normothermia. Based on routine blood gas analysis, hemoglobin, PaCO_2, and PaO₂ data were matched to 2-h averaged data of continuous CPP, P_btO₂, core temperature, and to hourly cerebral microdialysis (CMD) samples over the first 11 days.

RESULTS

Patients had a Glasgow Coma Scale of 3 (IQR 3-4) and were 58 years old (IQR 48-66). Overall incidence of brain tissue hypoxia was 25%, which was not different between both sites despite differences in the treatment approach. During brain tissue hypoxia, episodes of CPP < 70 mmHg (27%), PaCO₂ < 35 mmHg (19%), PaO₂ < 80 mmHg (14%), Hb < 9 g/dL (11%), metabolic crisis (CMD-lactate/pyruvate ratio > 40, and CMD-glucose < 0.7 mmol/L; 7%), and temperature > 38.3 °C (4%) were common.

CONCLUSIONS

Our results demonstrate that brain tissue hypoxia remains common despite implementation of a P_btO₂-targeted therapy in poor-grade SAH patients, suggesting room for further optimization.

Fever Is Associated with Reduced Mortality in Trauma and Surgical Intensive Care Unit-Acquired Infections

Background: Fever is a common response to both infectious and non-infectious physiologic insults in the critically ill, and in certain populations it appears to be protective. Fever is particularly common in trauma patients, and even more so in those with infections. The relationship between fever, trauma status, and mortality in patients with an infection is unclear. Patients and Methods: A review of a prospectively maintained institutional database over a 17-year period was performed. Surgical and trauma intensive care unit (ICU) patients with a nosocomial infection were extracted to compare in-hospital mortality among trauma and non-trauma patients with and without fever. Univariable analyses compared patient and infection characteristics between trauma and non-trauma patients. A multivariable logistic regression model was created to identify predictors of in-hospital mortality, with a focus on fever and trauma status. Results: Nine hundred forty-one trauma patients and 1,449 non-trauma patients with ICU-acquired infections were identified. Trauma patients were younger (48 vs. 59, p < 0.001), more likely to be male (73% vs. 56%, p < 0.001), more likely to require blood transfusion (74% vs. 47%, p < 0.001), had lower Acute Physiology and Chronic Health Evaluation (APACHE) II scores (18 vs. 19, p = 0.02), and had lower rates of comorbidities. Trauma patients were more likely to develop a fever (72% vs. 43%, p < 0.001) and had lower in-hospital mortality (9.6% vs. 22.6%, p < 0.001). In multivariable analysis, non-trauma patients with fever had a lower odds of mortality compared with non-trauma patients without fever (odds ratio [OR] 0.63, p = 0.004). Trauma patients with fever had the lowest odds ratio for mortality when compared to non-trauma patients without fever (OR 0.25, p < 0.001). Conclusions: In this large cohort of trauma and surgical ICU patients with ICU-acquired infections, fever was associated with a lower odds of mortality in both trauma and non-trauma patients. Further investigation is needed to determine the mechanisms behind the interplay between trauma status, fever, and mortality.

Effects of the Incidence Density of Fever (IDF) on Patients Resuscitated From In-Hospital Cardiac Arrest: A Mediation Analysis

Objective: The aim of this research was to study the factors contributing to the survival rate of in-hospital cardiac arrest (IHCA) and to determine whether the incidence density of fever (IDF) acts as a mediator.

Methods: Data from patients with IHCA who survived more than 48 h were collected from 2011 to 2017. IDF was defined as the fever duration divided by the hospitalization duration, prolonged fever was defined as fever lasting for more than 5 days, and early fever was defined as an initial onset within the first 2 days of IHCA. Possible clinical variables associated with IDF were examined by linear regression, and possible clinical variables associated with survival rate were examined by univariate and multivariate analyses. IDF was investigated as a mediator of the indirect effects of the risk factors on survival.

Results: In our retrospective study, the median IDF was 0, with an interquartile range from 0 to 0.42. Prolonged fever was noted in 16% (97/605) of the total, and early fever was noted in 17.2% (104/605) of the total. Linear regression results showed that positive chest X-ray, central venous catheter and Glasgow Coma Score (GCS) ≤ 8 were related to IDF. The IDF (OR: 0.36, 95% CI, 0.13–0.97, P = 0.04), prolonged fever (adjusted OR = 0.13, 95% CI, 0.06–0.29, P < 0.001), positive chest X-ray (OR: 0.67, 95% CI, 0.46–0.98, P = 0.04), central venous catheter placement (OR: 0.54, 95% CI, 0.34–0.89, P = 0.01), and endotracheal intubation (OR: 0.47, 95% CI, 0.33–0.69, P < 0.001) were also related to the negative outcome of hospital discharge after adjustment. Additionally, positive chest X-ray had a 19% effect on survival outcome through IDF as a mediator, and the indirect effect of central venous catheter mediated by IDF accounted for 10% of the total.

Conclusions: A higher IDF, prolonged fever, a positive chest X-ray, the use of a central venous catheter and endotracheal intubation reduced the survival rate of these patients, and the detrimental impacts of a positive chest X-ray and the use of a central venous catheter on survival outcomes were partially mediated by IDF.

Early Brain Injury After Poor-Grade Subarachnoid Hemorrhage

PURPOSE OF REVIEW

Over the last years, the focus of clinical and animal research in subarachnoid hemorrhage (SAH) shifted towards the early phase after the bleeding based on the association of the early injury pattern (first 72 h) with secondary complications and poor outcome. This phase is commonly referenced as early brain injury (EBI). In this clinical review, we intended to overview commonly used definitions of EBI, underlying mechanisms, and potential treatment implications.

RECENT FINDINGS

We found a large heterogeneity in the definition used for EBI comprising clinical symptoms, neuroimaging parameters, and advanced neuromonitoring techniques. Although specific treatments are currently not available, therapeutic interventions are aimed at ameliorating EBI by improving the energy/supply mismatch in the early phase after SAH. Future research integrating brain-derived biomarkers is warranted to improve our pathophysiologic understanding of EBI in order to ameliorate early injury patterns and improve patients' outcomes.

Targeted Temperature Management in Brain Injured Patients

Evidence from animal models indicates that lowering temperature by a few degrees can produce substantial neuroprotection. In humans, hypothermia has been found to be neuroprotective with a significant impact on mortality and long-term functional outcome only in cardiac arrest and neonatal hypoxic-ischemic encephalopathy. Clinical trials have explored the potential role of maintaining normothermia and treating fever in critically ill brain injured patients. This review concentrates on basic concepts to understand the physiologic interactions of thermoregulation, effects of thermal modulation in critically ill patients, proposed mechanisms of action of temperature modulation, and practical aspects of targeted temperature management.

Targeted Temperature Management in Brain Injured Patients

Evidence from animal models indicates that lowering temperature by a few degrees can produce substantial neuroprotection. In humans, hypothermia has been found to be neuroprotective with a significant impact on mortality and long-term functional outcome only in cardiac arrest and neonatal hypoxic-ischemic encephalopathy. Clinical trials have explored the potential role of maintaining normothermia and treating fever in critically ill brain injured patients. This review concentrates on basic concepts to understand the physiologic interactions of thermoregulation, effects of thermal modulation in critically ill patients, proposed mechanisms of action of temperature modulation, and practical aspects of targeted temperature management.

Is there still a role for hypothermia in neurocritical care?

PURPOSE OF REVIEW

Therapeutic hypothermia (i.e. induced body core temperature ≈ 33-35°C) in neurological patients with cerebrovascular disease and traumatic brain injury is a controversially discussed issue in the literature. In this review, we have included the most recently published research covering the use of therapeutic hypothermia and targeted temperature management in neurologic diseases and translated the results into a clinical decision support for the professional healthcare community.

RECENT FINDINGS

Recent findings from large multicenter studies investigating therapeutic hypothermia in patients with various acute neurologic diseases have revealed that although short-term and long-term temperature modulation on different temperature levels is feasible with the latest device technology, the effect on outcome is controversial.

SUMMARY

There is overwhelming evidence that fever is an independent predictor of morbidity and mortality in patients with acute severe neurologic diseases. Although therapeutic hypothermia has been proven to be a potent neuroprotective measure acting on various levels in animal models, many questions such as optimal depth of target temperature, speed of rewarming, duration of cooling and management of side-effects accompanying therapeutic hypothermia are unresolved in human. Therefore, the application of therapeutic hypothermia outside of strictly supervised clinical trials must be carefully considered.

Brain temperature but not core temperature increases during spreading depolarizations in patients with spontaneous intracerebral hemorrhage

Spreading depolarizations (SDs) are highly active metabolic events, commonly occur in patients with intracerebral hemorrhage (ICH) and may be triggered by fever. We investigated the dynamics of brain-temperature (T_brain) and core-temperature (T_core) relative to the occurrence of SDs. Twenty consecutive comatose ICH patients with multimodal electrocorticograpy (ECoG) and T_brain monitoring of the perihematomal area were prospectively enrolled. Clusters of SDs were defined as ≥2 SDs/h. Generalized estimating equations were used for statistical calculations. Data are presented as median and interquartile range. During 3097 h (173 h [81-223]/patient) of ECoG monitoring, 342 SDs were analyzed of which 51 (15%) occurred in clusters. Baseline T_core and T_brain was 37.3℃ (36.9-37.8) and 37.4℃ (36.7-37.9), respectively. T_brain but not T_core significantly increased 25 min preceding the onset of SDs by 0.2℃ (0.1-0.2; p < 0.001) and returned to baseline 35 min following SDs. During clusters, T_brain increased to a higher level (+0.4℃ [0.1-0.4]; p = 0.006) when compared to single SDs. A higher probability (OR = 36.9; CI = 36.8-37.1; p < 0.001) of developing SDs was observed during episodes of T_brain ≥ 38.0℃ (23% probability), than during T_brain ≤ 36.6℃ (9% probability). Spreading depolarizations - and in particular clusters of SDs - may increase brain temperature following ICH.

Early fever after trauma: Does it matter?

BACKGROUND

Fever is strongly associated with poor outcome after traumatic brain injury (TBI). We hypothesized that early fever is a direct result of brain injury and thus would be more common in TBI than in patients without brain injury and associated with inflammation.

METHODS

We prospectively enrolled patients with major trauma with and without TBI from a busy Level I trauma center intensive care unit (ICU). Patients were assigned to one of four groups based on their presenting Head Abbreviated Injury Severity Scale scores: multiple injuries: head Abbreviated Injury Scale (AIS) score greater than 2, one other region greater than 2; isolated head: head AIS score greater than 2, all other regions less than 3; isolated body: one region greater than 2, excluding head/face; minor injury: no region with AIS greater than 2. Early fever was defined as at least one recorded temperature greater than 38.3°C in the first 48 hours after admission. Outcome measures included neurologic deterioration, length of stay in the ICU, hospital mortality, discharge Glasgow Outcome Scale-Extended, and plasma levels of seven key cytokines at admission and 24 hours (exploratory).

RESULTS

Two hundred sixty-eight patients were enrolled, including subjects with multiple injuries (n = 59), isolated head (n = 97), isolated body (n = 100), and minor trauma (n = 12). The incidence of fever was similar in all groups irrespective of injury (11-24%). In all groups, there was a significant association between the presence of early fever and death in the hospital (6-18% vs. 0-3%), as well as longer median ICU stays (3-7 days vs. 2-3 days). Fever was significantly associated with elevated IL-6 at admission (50.7 pg/dL vs. 16.9 pg/dL, p = 0.0067) and at 24 hours (83.1 pg/dL vs. 17.1 pg/dL, p = 0.0025) in the isolated head injury group.

CONCLUSION

Contrary to our hypothesis, early fever was not more common in patients with brain injury, though fever was associated with longer ICU stays and death in all groups. Additionally, fever was associated with elevated IL-6 levels in isolated head injury.

LEVEL OF EVIDENCE

Prognostic and Epidemiological study, level III.

Neurogenic Fever

Fever is a relatively common occurrence among patients in the intensive care setting. Although the most obvious and concerning etiology is sepsis, drug reactions, venous thromboembolism, and postsurgical fevers are all on the differential diagnosis. There is abundant evidence that fever is detrimental in acute neurologic injury. Worse outcomes are reported in acute stroke, subarachnoid hemorrhage, and traumatic brain injury. In addition to the various etiologies of fever in the intensive care setting, neurologic illness is a risk factor for neurogenic fevers. This primarily occurs in subarachnoid hemorrhage and traumatic brain injury, with hypothalamic injury being the proposed mechanism. Paroxysmal sympathetic hyperactivity is another source of hyperthermia commonly seen in the population with traumatic brain injury. This review focuses on the detrimental effects of fever on the neurologically injured as well as the risk factors and diagnosis of neurogenic fever.

Clinical factors and incidence of prolonged fever in neurosurgical patients

AIMS AND OBJECTIVES

To describe the incidence of prolonged fever in patients admitted to the neurosurgery department, and the corresponding risk indicators.

BACKGROUND

Prolonged fever was defined as a temperature higher than 38·3°C lasting more than five days. Prolonged fever is a common phenomenon and could lead to worsened outcomes in specific patient groups, especially for those with brain injury. However, the studies on prolonged fever in neurosurgical patients are limited and insufficient.

DESIGN

A retrospective observational study.

METHODS

Retrospective data were collected from 1 January 2014 to 31 December 2014, at the neurosurgical department of a large teaching hospital. We performed univariate and multivariate analyses to identify independent indicators for prolonged fever vs. short-term fever.

RESULTS

Among 2845 patients, prolonged fever occurred in 466 (16%). The older patients were associated with longer duration of mechanical ventilation and hospital stay. It predominantly occurred in patients with subarachnoid haemorrhage (SAH) and traumatic brain injury. Patients receiving antibiotic treatment tended to manifest prolonged fever more frequently. Multivariate analysis revealed that the use of antibiotics, central venous catheter and prolonged mechanical ventilation were independent risk predictors for prolonged fever. Patients diagnosed with brain tumour seemed to be not associated with prolonged fever.

CONCLUSIONS

Prolonged fever is the common complication in neurosurgical patients. The risks of prolonged fever in patients are attributed to antibiotic therapy, use of central venous catheter and prolonged mechanical ventilation. Indicators of prolonged fever are helpful for better identification of high-risk patients and fever control.

RELEVANCE TO CLINICAL PRACTICE

A better reveal on the epidemiology and predictable factors of prolonged fever in neurosurgical patients will provide a better understanding on those patients who are most at risk, and therefore contribute to fever control and better outcome.

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.

Fever in trauma patients: evaluation of risk factors, including traumatic brain injury

BACKGROUND

The role of fever in trauma patients remains unclear. Fever occurs as a response to release of cytokines and prostaglandins by white blood cells. Many factors, including trauma, can trigger release of these factors.

OBJECTIVES

To determine whether (1) fever in the first 48 hours is related to a favorable outcome in trauma patients and (2) fever is more common in patients with head trauma.

METHOD

Retrospective study of trauma patients admitted to the intensive care unit for at least 2 days. Data were analyzed by using multivariate analysis.

RESULTS

Of 162 patients studied, 40% had fever during the first 48 hours. Febrile patients had higher mortality rates than did afebrile patients. When adjusted for severity of injuries, fever did not correlate with mortality. Neither the incidence of fever in the first 48 hours after admission to the intensive care unit nor the number of days febrile in the unit differed between patients with and patients without head trauma (traumatic brain injury). About 70% of febrile patients did not have a source found for their fever. Febrile patients without an identified source of infection had lower peak white blood cell counts, lower maximum body temperature, and higher minimum platelet counts than did febrile patients who had an infectious source identified. The most common infection was pneumonia.

CONCLUSIONS

No relationship was found between the presence of fever during the first 48 hours and mortality. Patients with traumatic brain injury did not have a higher incidence of fever than did patients without traumatic brain injury. About 30% of febrile patients had an identifiable source of infection. Further studies are needed to understand the origin and role of fever in trauma patients.

Neurotrauma

Neurotrauma continues to be a significant cause of morbidity and mortality. Prevention of primary neurologic injury is a critical public health concern. Early and thorough assessment of the patient with neurotrauma with high index of suspicion of traumatic spinal cord injuries and traumatic vascular injuries requires a multidisciplinary approach involving prehospital providers, emergency physicians, neurosurgeons, and neurointensivists. Critical care management of the patient with neurotrauma is focused on the prevention of secondary injuries. Much research is still needed for potential neuroprotection therapies.