Clinical review: fever in septic ICU patients--friend or foe?

Early changes in skin surface temperature predict body temperature increases in patients with fever: A pilot study

OBJECTIVE

To investigate the correlation between body temperature and skin surface temperature in intensive care unit patients and to identify specific indicators of skin surface temperature for early fever detection.

RESEARCH METHODOLOGY/DESIGN

This pilot study was a prospective, observational investigation conducted at National Cheng Kung University Hospital in Tainan, Taiwan. A total of 54 patients admitted to the Surgical Intensive Care Unit of a tertiary hospital between April and August 2020 were included. Patients utilized the wearable device HEARThremoTM to continuously monitor skin surface temperature and heart rate. Analysis of Variance was applied to identify the association of skin surface temperature with different body temperature groups. The comparison between skin surface temperature and fever over eight time intervals was studied using a generalized estimating equation.

RESULTS

In 34 patients (63 %) with a fever (≥38 °C), skin surface temperature increased (P < 0.001) when body temperature increased. The maximum skin surface temperature was significantly associated with fever 180-210 min before the fever events occurred (OR: 2.22, 95 % CI: 1.30-3.80). The mean skin surface temperature was associated with fever 120-150 min before the fever events (OR: 8.70, 95 % CI: 2.08-36.36).

CONCLUSIONS

Skin surface temperature can be an important early predictive sign before the onset of fever. Continuous temperature monitoring can detect fever early and initiate treatment in advance. This study serves as a preliminary exploration in this area, laying the groundwork for future comprehensive research.

IMPLICATIONS FOR CLINICAL PRACTICE

Continuous monitoring of skin surface temperature empowers nurses to swiftly detect fever, transcending conventional methods. This proactive approach allows for the early identification of physiological abnormalities, facilitating the prompt initiation of further physical assessments and relevant examinations for early treatment commencement.

Evaluation of disease severity and prediction of severe cases in children hospitalized with influenza A (H1N1) infection during the post-COVID-19 era: a multicenter retrospective study

BACKGROUND

The rebound of influenza A (H1N1) infection in post-COVID-19 era recently attracted enormous attention due the rapidly increased number of pediatric hospitalizations and the changed characteristics compared to classical H1N1 infection in pre-COVID-19 era. This study aimed to evaluate the clinical characteristics and severity of children hospitalized with H1N1 infection during post-COVID-19 period, and to construct a novel prediction model for severe H1N1 infection.

METHODS

A total of 757 pediatric H1N1 inpatients from nine tertiary public hospitals in Yunnan and Shanghai, China, were retrospectively included, of which 431 patients diagnosed between February 2023 and July 2023 were divided into post-COVID-19 group, while the remaining 326 patients diagnosed between November 2018 and April 2019 were divided into pre-COVID-19 group. A 1:1 propensity-score matching (PSM) was adopted to balance demographic differences between pre- and post-COVID-19 groups, and then compared the severity across these two groups based on clinical and laboratory indicators. Additionally, a subgroup analysis in the original post-COVID-19 group (without PSM) was performed to investigate the independent risk factors for severe H1N1 infection in post-COIVD-19 era. Specifically, Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to select candidate predictors, and logistic regression was used to further identify independent risk factors, thus establishing a prediction model. Receiver operating characteristic (ROC) curve and calibration curve were utilized to assess discriminative capability and accuracy of the model, while decision curve analysis (DCA) was used to determine the clinical usefulness of the model.

RESULTS

After PSM, the post-COVID-19 group showed longer fever duration, higher fever peak, more frequent cough and seizures, as well as higher levels of C-reactive protein (CRP), interleukin 6 (IL-6), IL-10, creatine kinase-MB (CK-MB) and fibrinogen, higher mechanical ventilation rate, longer length of hospital stay (LOS), as well as higher proportion of severe H1N1 infection (all P < 0.05), compared to the pre-COVID-19 group. Moreover, age, BMI, fever duration, leucocyte count, lymphocyte proportion, proportion of CD3+ T cells, tumor necrosis factor α (TNF-α), and IL-10 were confirmed to be independently associated with severe H1N1 infection in post-COVID-19 era. A prediction model integrating these above eight variables was established, and this model had good discrimination, accuracy, and clinical practicability.

CONCLUSIONS

Pediatric H1N1 infection during post-COVID-19 era showed a higher overall disease severity than the classical H1N1 infection in pre-COVID-19 period. Meanwhile, cough and seizures were more prominent in children with H1N1 infection during post-COVID-19 era. Clinicians should be aware of these changes in such patients in clinical work. Furthermore, a simple and practical prediction model was constructed and internally validated here, which showed a good performance for predicting severe H1N1 infection in post-COVID-19 era.

Systematic Literature Review of the Association of Fever and Elevated Temperature with Outcomes in Critically Ill Adult Patients

Although most commonly associated with infection, elevated temperature and fever also occur in a variety of critically ill populations. Prior studies have suggested that fever and elevated temperature may be detrimental to critically ill patients and can lead to poor outcomes, but the evidence surrounding the association of fever with outcomes is rapidly evolving. To broadly assess potential associations of elevated temperature and fever with outcomes in critically ill adult patients, we performed a systematic literature review focusing on traumatic brain injury, stroke (ischemic and hemorrhagic), cardiac arrest, sepsis, and general intensive care unit (ICU) patients. Searches were conducted in Embase® and PubMed® from 2016 to 2021, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including dual-screening of abstracts, full texts, and extracted data. In total, 60 studies assessing traumatic brain injury and stroke (24), cardiac arrest (8), sepsis (22), and general ICU (6) patients were included. Mortality, functional, or neurological status and length of stay were the most frequently reported outcomes. Elevated temperature and fever were associated with poor clinical outcomes in patients with traumatic brain injury, stroke, and cardiac arrest but not in patients with sepsis. Although a causal relationship between elevated temperature and poor outcomes cannot be definitively established, the association observed in this systematic literature review supports the concept that management of elevated temperature may factor in avoidance of detrimental outcomes in multiple critically ill populations. The analysis also highlights gaps in our understanding of fever and elevated temperature in critically ill adult patients.

Temperature impacts the bovine ex vivo immune response towards Mycoplasmopsis bovis

Although cattle are the mammalian species with most global biomass associated with a huge impact on our planet, their immune system remains poorly understood. Notably, the bovine immune system has peculiarities such as an overrepresentation of γδ T cells that requires particular attention, specifically in an infectious context. In line of 3R principles, we developed an ex vivo platform to dissect host-pathogen interactions. The experimental design was based on two independent complementary readouts: firstly, a novel 12-14 color multiparameter flow cytometry assay measuring maturation (modulation of cell surface marker expression) and activation (intracellular cytokine detection) of monocytes, conventional and plasmacytoid dendritic cells, natural killer cells, γδ T cells, B and T cells; secondly, a multiplex immunoassay monitoring bovine chemokine and cytokine secretion levels. The experiments were conducted on fresh primary bovine blood cells exposed to Mycoplasmopsis bovis (M. bovis), a major bovine respiratory pathogen. Besides reaffirming the tight cooperation of the different primary blood cells, we also identified novel key players such as strong IFN-γ secreting NK cells, whose role was so far largely overlooked. Additionally, we compared the host-pathogen interactions at different temperatures, including commonly used 37 °C, ruminant body temperature (38-38.5 °C) and fever (≥ 39.5 °C). Strikingly, working under ruminant physiological temperature influenced the capacity of most immune cell subsets to respond to M. bovis compared to 37 °C. Under fever-like temperature conditions the immune response was impaired compared to physiological temperature. Our experimental approach, phenotypically delineating the bovine immune system provided a thorough vision of the immune response towards M. bovis and the influence of temperature towards that immune response.

Association of body temperature and mortality in critically ill patients: an observational study using two large databases

BACKGROUND

Body temperature (BT) is routinely measured and can be controlled in critical care settings. BT can impact patient outcome, but the relationship between BT and mortality has not been well-established.

METHODS

A retrospective cohort study was conducted based on the MIMIC-IV (N = 43,537) and eICU (N = 75,184) datasets. The primary outcome and exposure variables were hospital mortality and first 48-h median BT, respectively. Generalized additive models were used to model the associations between exposures and outcomes, while adjusting for patient age, sex, APS-III, SOFA, and Charlson comorbidity scores, temperature gap, as well as ventilation, vasopressor, steroids, and dialysis usage. We conducted subgroup analysis according to ICU setting, diagnoses, and demographics.

RESULTS

Optimal BT was 37 °C for the general ICU and subgroup populations. A 10% increase in the proportion of time that BT was within the 36-38 °C range was associated with reduced hospital mortality risk in both MIMIC-IV (OR 0.91; 95% CI 0.90-0.93) and eICU (OR 0.86; 95% CI 0.85-0.87). On the other hand, a 10% increase in the proportion of time when BT < 36 °C was associated with increased mortality risk in both MIMIC-IV (OR 1.08; 95% CI 1.06-1.10) and eICU (OR 1.18; 95% CI 1.16-1.19). Similarly, a 10% increase in the proportion of time when BT > 38 °C was associated with increased mortality risk in both MIMIC-IV (OR 1.09; 95% CI 1.07-1.12) and eICU (OR 1.09; 95% CI 1.08-1.11). All patient subgroups tested consistently showed an optimal temperature within the 36-38 °C range.

CONCLUSIONS

A BT of 37 °C is associated with the lowest mortality risk among ICU patients. Further studies to explore the causal relationship between the optimal BT and mortality should be conducted and may help with establishing guidelines for active BT management in critical care settings.

Current State of Knowledge on the Definition, Pathophysiology, Etiology, Outcomes, and Management of Fever in the Intensive Care Unit

Fever-an elevated body temperature-is a prominent feature of a wide range of disease conditions and is a common finding in intensive care, affecting up to 70% of patients in the intensive care unit (ICU). The causes of fever in the ICU are multifactorial, and it can be due to a number of infective and noninfective etiologies. The production of fever represents a complex physiological, adaptive host response that is beneficial for host defense and survival but can be maladaptive and harmful if left unabated. Despite any cause, fever is associated with a wide range of cellular, local, and systemic effects, including multiorgan dysfunction, systemic inflammation, poor neurological recovery, and an increased risk of mortality. This narrative review presents the current state-of-the-art knowledge on the definition, pathophysiology, etiology, and outcomes of fever in the ICU and highlights evidence-based findings regarding the management of fever in the intensive care setting.

Core Warming of Coronavirus Disease 2019 Patients Undergoing Mechanical Ventilation: A Pilot Study

Fever is a recognized protective factor in patients with sepsis, and growing data suggest beneficial effects on outcomes in sepsis with elevated temperature, with a recent pilot randomized controlled trial (RCT) showing lower mortality by warming afebrile sepsis patients in the intensive care unit (ICU). The objective of this prospective single-site RCT was to determine if core warming improves respiratory physiology of mechanically ventilated patients with coronavirus disease 2019 (COVID-19), allowing earlier weaning from ventilation, and greater overall survival. A total of 19 patients with mean age of 60.5 (±12.5) years, 37% female, mean weight 95.1 (±18.6) kg, and mean body mass index 34.5 (±5.9) kg/m2 with COVID-19 requiring mechanical ventilation were enrolled from September 2020 to February 2022. Patients were randomized 1:1 to standard of care or to receive core warming for 72 hours through an esophageal heat exchanger commonly utilized in critical care and surgical patients. The maximum target temperature was 39.8°C. A total of 10 patients received usual care and 9 patients received esophageal core warming. After 72 hours of warming, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2) ratios were 197 (±32) and 134 (±13.4), cycle thresholds were 30.8 (±6.4) and 31.4 (±3.2), ICU mortalities were 40% and 44%, 30-day mortalities were 30% and 22%, and mean 30-day ventilator-free days were 11.9 (±12.6) and 6.8 (±10.2) for standard of care and warmed patients, respectively (p = NS). This pilot study suggests that core warming of patients with COVID-19 undergoing mechanical ventilation is feasible and appears safe. Optimizing time to achieve febrile-range temperature may require a multimodal temperature management strategy to further evaluate effects on outcome. ClinicalTrials.gov Identifier: NCT04494867.

Association between circadian body temperature rhythm during the first 24 hours of ICU stay and 28-day mortality in elderly critically ill patients: A retrospective cohort study

Disrupted circadian temperature rhythm is commonly observed in elderly patients in the intensive care unit (ICU), but the association between circadian temperature rhythm and mortality in elderly patients is unclear. Adult patients with a relatively complete record of body temperature (BT) during the first 24 hours of ICU stay in the Multi-parameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database were included in this retrospective cohort study. The circadian rhythm of body temperature was blunted as a ratio of the maximum BT between 12:00 and 24:00 divided by the minimum BT between 0:00 and 12:00, and we defined it as BT fluctuation ratio. The associations of BT fluctuation ratio with 28-day mortality were assessed separately using Cox proportional hazards model in elderly patients and non-elderly patients. The overall cohort comprised 12 767 patients. After adjusting for covariates, the analysis showed that the BT fluctuation ratio (%) was significantly associated with mortality at 28 days in total patients (hazard ratio: 1.044; 95% CI 1.001-1.088; P = 0.042), and still significantly in elderly patients (hazard ratio 1.055, 95% CI as 1.004-1.109, p = 0.035), but not significantly in non-elderly patients. The implementation of restricted cubic splines demonstrated a nonlinear correlation between the ratio of BT fluctuation and the hazard ratio of 28-day mortality, indicating that increased diurnal temperature fluctuations are linked to elevated risk of mortality. This study revealed that the augmented amplitude of the circadian rhythm of body temperature in the elderly patients constitutes a risk factor for the rise of 28-day mortality. Additionally, the circadian body temperature rhythm may facilitate the early detection of critically ill elderly patients.

Towards Simultaneous Noninvasive Arterial and Venous Oxygenation Monitoring with Wearable E-Tattoo

While noninvasive arterial blood oxygenation is easily estimated using peripheral pulse oximeters, noninvasive venous blood oxygenation monitoring is still a critical unmet need. Critical conditions that lead to inefficient extraction of oxygen from the blood, such as sepsis or shock, can only be detected by analyzing the oxygen content of the venous blood. In this work, we introduce a soft wearable e-tattoo sensor that simultaneously measures the arterial and venous pulses from the wrist. First, we prove that the origin of the signal is venous pulsatility. We hypothesize that a significant obstacle for simultaneous SaO2 and SvO2 extraction is the close proximity of the artery and vein, thus leading to crosstalk. We characterize this crosstalk with simulation, in vitro, and in vivo experiments. Finally, we offer a potential solution for minimizing the crosstalk through spatial filtering.Clinical Relevance- This lays foundational work for a novel method of noninvasively and simultaneously measuring arterial and venous blood oxygenation to improve clinical diagnoses of sepsis, shock, and metabolic abnormalities.

Association between variables measured in the ambulance and in-hospital mortality among adult patients with and without infection: a prospective cohort study

BACKGROUND

Patients presenting with infection to the ambulance are common, but risk factors for poor outcome are not known. The primary aim of the current study was to study the association between variables measured in the ambulance and mortality among adult patients with and without infection. The secondary aim was to study the association between these variables and mortality in a subgroup of patients who developed sepsis within 36 h.

METHODS

Prospective cohort study of 553 ambulance patients with, and 318 patients without infection, performed in Stockholm during 2017-2018. The association between 21 variables (8 keywords related to medical history, 6 vital signs, 4 blood tests, and age, gender, comorbidity) and in-hospital mortality was analysed using logistic regression.

RESULTS

Among patients with infection, inability of the patient to answer questions relating to certain symptoms such as pain and gastrointestinal symptoms was significantly associated with mortality in univariable analysis, in addition to oxygen saturation < 94%, heart rate > 110 /min, Glasgow Coma Scale (GCS) < 15, soluble urokinase Plasminogen Activator Receptor (suPAR) 4.0-7.9 ng/mL, suPAR ≥ 8.0 ng/mL and a Charlson comorbidity score ≥ 5. suPAR ≥ 8.0 ng/mL remained significant in multivariable analysis (OR 25.4; 95% CI, 3.2-199.8). Among patients without infection, suPAR ≥ 8.0 ng/mL and a Charlson comorbidity score ≥ 5 were significantly associated with mortality in univariable analysis, while suPAR ≥ 8.0 ng/mL remained significant in multivariable analysis (OR 56.1; 95% CI, 4.5-700.0). Among patients who developed sepsis, inability to answer questions relating to pain remained significant in multivariable analysis (OR 13.2; 95% CI, 2.2-78.9), in addition to suPAR ≥ 8.0 ng/mL (OR 16.1; 95% CI, 2.0-128.6).

CONCLUSIONS

suPAR ≥ 8.0 ng/mL was associated with mortality in patients presenting to the ambulance both with and without infection and in those who developed sepsis. Furthermore, the inability of the ambulance patient with an infection to answer questions relating to specific symptoms was associated with a surprisingly high mortality. These results suggest that suPAR and medical history are valuable tools with which to identify patients at risk of poor outcome in the ambulance and could potentially signal the need of enhanced attention.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03249597. Registered 15 August 2017-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03249597 .

Impact of an Educational Program on Improving Nurses’ Management of Fever: An Experimental Study

Background: Despite a public information campaign “To Break the Myth of Fever”, nurses continued to overtreat fever. This study hypothesized that the campaign lacked the detailed rationale essential to alter nurses’ attitudes and behaviors. Aim: To evaluate the effect of the educational program on nurses’ knowledge, attitudes, and behaviors related to fever management. Design: A randomized experimental design using a time series analysis. Methods: A random sample of 58 medical/surgical nurses was evenly divided into an intervention and a control group. The intervention group received an educational program on fever and fever management. Both groups completed a pretest and four posttests using investigator-developed instruments: a questionnaire on knowledge and attitudes about fever management and a fever treatment checklist to audit charts. Results: The intervention group had markedly higher knowledge scores and reduced use of ice pillows at all four posttests, as well as lower use of antipyretics overall, except for the first posttest, despite no sustained change in attitude. Conclusions: An educational program for fever management can effectively improve clinical nurses’ knowledge and attitudes about fever management.

Temperature Management in the ICU

OBJECTIVE

Temperature abnormalities are recognized as a marker of human disease, and the therapeutic value of temperature is an attractive treatment target. The objective of this synthetic review is to summarize and critically appraise evidence for active temperature management in critically ill patients.

DATA SOURCES

We searched MEDLINE for publications relevant to body temperature management (including targeted temperature management and antipyretic therapy) in cardiac arrest, acute ischemic and hemorrhagic stroke, traumatic brain injury, and sepsis. Bibliographies of included articles were also searched to identify additional relevant studies.

STUDY SELECTION

English-language systematic reviews, meta-analyses, randomized trials, observational studies, and nonhuman data were reviewed, with a focus on the most recent randomized control trial evidence.

DATA EXTRACTION

Data regarding study methodology, patient population, temperature management strategy, and clinical outcomes were qualitatively assessed.

DATA SYNTHESIS

Temperature management is common in critically ill patients, and multiple large trials have been conducted to elucidate temperature targets, management strategies, and timing. The strongest data concerning the use of therapeutic hypothermia exist in comatose survivors of cardiac arrest, and recent trials suggest that appropriate postarrest temperature targets between 33°C and 37.5°C are reasonable. Targeted temperature management in other critical illnesses, including acute stroke, traumatic brain injury, and sepsis, has not shown benefit in large clinical trials. Likewise, trials of pharmacologic antipyretic therapy have not demonstrated improved outcomes, although national guidelines do recommend treatment of fever in patients with stroke and traumatic brain injury based on observational evidence associating fever with worse outcomes.

CONCLUSIONS

Body temperature management in critically ill patients remains an appealing therapy for several illnesses, and additional studies are needed to clarify management strategies and therapeutic pathways.

HEPATIC DYSFUNCTION IN MEDICAL INTENSIVE CAREUNIT PATIENTS PREDICTS POOR OUTCOME

BACKGROUND

A large number of patients admitted to the medical intensive care unit (MICU) have abnormal liver function tests (LFT). This includes patients with critical illness with or without preexisting liver disease and patients with acute primary liver injury. There are very few studies which have investigated the spectrum of liver disease, clinical profile and outcome in patients admitted to the MICU.

OBJECTIVE

To evaluate the occurrence, etiology, clinical profile, laboratory profile and outcome of hepatic dysfunction in patients admitted to the MICU. To evaluate the utility of model for end-stage liver disease (MELD) score on admission as a predictor of adverse short term outcome in patients with hepatic dysfunction admitted in MICU.

METHODS

It was a prospective observational study, conducted from December 2017 to December 2018 in a tertiary care hospital. Two hundred and two patients admitted to the MICU with LFTs as per the inclusion criteria were analyzed and their short-term outcome at 7 days was studied in relation to various parameters.

RESULTS

LFT abnormalities were present in 202/1126 (17.9%) of the patients admitted to MICU. Critical illness associated liver dysfunction was found in 172 (85.2%) patients, chronic liver disease in 11 (5.4%) patients and acute viral hepatitis in 19 (9.4%) patients. Most common symptom was fever (68.3%) followed by vomiting (48.0%). Among LFT abnormalities, elevated transaminases, raised international normalized ratio and high MELD score on admission correlated with poor short-term outcome. Requirement for inotropes and mechanical ventilation correlated with poor short-term outcome. Mortality did not differ significantly between patients with chronic liver disease, patients with acute viral hepatitis and patients with critical illness associated hepatic dysfunction. Hepatic dysfunction in MICU was associated with poor outcome and a high short-term mortality of 56.4% (114/202).

CONCLUSION

Liver function abnormality is common in patients who are admitted to the MICU and its presence is an indicator of poor short-term outcome.

Development and Validation of Nomogram for Hospital Mortality in Immunocompromised Patients with Severe Pneumonia in Intensive Care Units: A Single-Center, Retrospective Cohort Study

Purpose

Risk factors and prognostic model of fatal outcomes need to be investigated for the increasing number of immunocompromised hosts (ICHs) who are hospitalized for severe pneumonia with high hospital mortality.

Patients and Methods

In this single-center, retrospective study, we recruited 1,933 ICHs with severe pneumonia who were admitted to the intensive care unit (ICU) in West China hospital, Sichuan university, China between January, 2012 and December, 2018. Clinical features, laboratory findings, and fatal outcomes were collected from electronic medical records. Patients were randomly separated into a 70% training set (n=1,353) and a 30% testing set (n=580) for the development and validation of a prediction model. All data within 24 hours of ICU admission were compared between survivors and non-survivors. The risk factors were identified through LASSO and multivariate logistic regression analysis, and then used to develop a predicting nomogram. The nomogram for predicting hospital mortality of ICHs with severe pneumonia in the ICU was validated by C-index, AUC (area under the curve), calibration curve, and Decision Curve Analysis (DCA).

Results

Eight risk factors, including age, fever, dyspnea, chronic renal disease, platelet counts, neutrophil counts, PaO₂/FiO₂ ratio, and the requirement for vasopressors, were adopted in a nomogram for predicting hospital mortality. The nomogram had great predicting accuracy with a C-index of 0.819 (95% CI=0.795–0.842) in the training set, and a C-index of 0.819 (95% CI=0.783–0.855) in the testing set for hospital mortality. Additionally, the nomogram had well-fitted calibration curves. DCA demonstrated that the nomogram was clinically beneficial.

Conclusion

This study developed a novel nomogram for predicting hospital mortality of ICHs with severe pneumonia in the ICU. Validation showed good discriminatory ability and calibration, indicating that the nomogram was expected to be a superior predictive tool for doctors to identify risk factors and predict mortality, and might be generally applied in clinical practice after more external validations.

Relationship Between First 24-h Mean Body Temperature and Clinical Outcomes of Post-cardiac Surgery Patients

Background: This study was aimed to investigate the relationship between first 24-h mean body temperature and clinical outcomes of post cardiac surgery patients admitted to intensive care unit (ICU) in a large public clinical database.

Methods: This is a retrospectively observational research of MIMIC III dataset, a total of 6,122 patients included. Patients were divided into 3 groups according to the distribution of body temperature. Multivariate cox analysis and logistic regression analysis were used to investigate the association between abnormal temperature, and clinical outcomes.

Results: Hypothermia (<36°C) significantly associated with increasing in-hospital mortality (HR 1.665, 95%CI 1.218–2.276; p = 0.001), 1-year mortality (HR 1.537, 95% CI 1.205–1.961; p = 0.001), 28-day mortality (HR 1.518, 95% CI 1.14–2.021; p = 0.004), and 90-day mortality (HR 1.491, 95% CI 1.144–1.943; p = 0.003). No statistical differences were observed between short-term or long-term mortality and hyperthermia (>38°C). Hyperthermia was related to the extended length of ICU stay (p < 0.001), and hospital stay (p < 0.001).

Conclusion: Hypothermia within 24h after ICU admission was associated with the increased mortality of post cardiac surgery patients. Enhanced monitoring of body temperature within 24h after cardiac surgery should be taken into account for improving clinical outcomes.

Early Fever Is Associated With Clinical Outcomes in Patients With Coronavirus Disease

Fever is one of the typical symptoms of coronavirus disease (COVID-19). We aimed to investigate the association between early fever (EF) and clinical outcomes in COVID-19 patients. A total of 1,014 COVID-19 patients at the Leishenshan Hospital were enrolled and classified into the EF and non-EF groups based on whether they had fever within 5 days of symptom onset. Risk factors for clinical outcomes in patients with different levels of disease severity were analyzed using multivariable analyses. Time from symptom onset to symptom alleviation, CT image improvement, and discharge were longer for patients with moderate and severe disease in the EF group than in the non-EF group. Multivariable analysis showed that sex, EF, eosinophil number, C-reactive protein, and IL-6 levels were positively correlated with the time from symptom onset to hospital discharge in moderate cases. The EF patients showed no significant differences in the development of acute respiratory distress syndrome, compared with the non-EF patients. The Kaplan–Meier curve showed no obvious differences in survival between the EF and non-EF patients. However, EF patients with increased temperature showed markedly lower survival than the non-EF patients with increased temperature. EF had no significant impact on the survival of critically ill patients, while an increase in temperature was identified as an independent risk factor. EF appears to be a predictor of longer recovery time in moderate/severe COVID-19 infections. However, its value in predicting mortality needs to be considered for critically ill patients with EF showing increasing temperature.

Cooling Blankets in Hospitalized Patients: Time to Reevaluate

BACKGROUND

The therapeutic benefits and rationale for treating fevers with external cooling methods remain unclear. We aimed to describe the clinical settings in which cooling blankets (CBs) are used.

DESIGN

We conducted a retrospective chart review of CB use in adult patients admitted to our tertiary care center over a one-year period. We measured how they are used and correlations between clinical variables and their duration of use.

RESULTS

561 patients were included in our study. The mean highest temperature during hospitalization was 39.35°C (SD, 0.67). Shivering occurred in 176 patients (31.4%) while on a CB although 303 patients (54%) had no data regarding shivering. Discontinuation of CBs was recorded in only 177 (30.5%) cases. Among these, the median duration of use was 33.37 hours (IQR: 18.13-80.38) while the median duration of fever was 22.13 hours (IQR 6.67-51.98). Duration of CB use was highly correlated with fever duration (Spearman's rho, 0.771, p<.001), moderately with length of stay (LOS) (rho, 0.425, p<.001), LOS after CB initiation (rho, 0.475, p<.001) and antipyretic use (rho, 0.506, p<.001). No other statistically significant correlations were observed.

CONCLUSION

Documentation of CB use including temperature set points, time of discontinuation and duration in EMRs was poor. We could not establish benefits of CB use in this study but observed that almost a third of patients developed adverse effects in the form of shivering. Thus, adverse effects of CB use may outweigh potential benefits. Their use should be reevaluated and institutional protocols developed for their use.

Genetic associations with a fever after measles-containing vaccines

Children have elevated fever risk 1 to 2 weeks after the first dose of a measles-containing vaccine (MCV), which is likely affected by genetic, immunologic, and clinical factors. Fever after MCV is associated with febrile seizures, though may also be associated with higher measles antibody titers. This exploratory study investigated genetic and immunologic associations with a fever after MCV. Concurrent with a randomized Phase 3 clinical trial of 12–15-month-olds who received their first measles-mumps-rubella (MMR) vaccine in which parents recorded post-vaccination temperatures daily, we consented a subset to collect additional blood and performed human leukocyte antigens (HLA) typing. Association between fever 5–12 days after MMR (“MMR-associated”) and HLA type was assessed using logistic regression. We compared 42-day post-vaccination geometric mean titers (GMT) to measles between children who did and did not have fever using a t-test. We enrolled 86 children and performed HLA typing on 82; 13 (15.1%) had MMR-associated fever. Logistic regressions identified associations between MMR-associated fever and HLA Class I loci A-29:02 (P = .036), B-57:01 (P = .018), C-06:02 (P = .006), C-14:02 (P = .022), and Class II loci DRB1-15 (P = .045). However, Bonferroni's adjustment for multiple comparisons suggests that these associations could have been due to chance. Ninety-eight percent of children had protective antibody titers to measles; however, GMT was higher among those with fever compared with children without fever (P = .006). Fever after the measles vaccine correlated with genetic factors and higher immune response. This study suggests a possible genetic susceptibility to MMR-associated fever.

Association of hypothermia with increased mortality rate in SARS-CoV-2 infection

OBJECTIVE

Patients were observed to have variable temperatures. The objective of this study was to identify whether hypothermia in a patient infected with SARS-CoV-2 was associated with a higher than expected mortality.

METHODS

In total, 331 charts from patients hospitalized with SARS-CoV-2 between March 9 and April 20, 2020 were reviewed.

RESULTS

The probability of death was 2.06 times higher for those with hypothermia than for those without (95% CI 1.25-3.38)]. In ventilated patients, there were 32 deaths. Of these, 75% had been hypothermic. In a prior review of 10 000 non-SARS-CoV-2 patients with sepsis, the mortality rate in patients with hypothermia was 47%. A review of previous studies demonstrated a range of expected mortality rates in patients with ventilator-dependent respiratory failure and sepsis. In comparison, our study showed that within a group of critically ill patients with SARS-CoV-2 and hypothermia, the mortality rate exceeded those rates.

CONCLUSION

Our review showed a significant association between hypothermia and death (p = 0.0033). Predictors of mortality in SARS-CoV-2 disease can expedite earlier aggressive care. Additionally, in areas with limited resources or overburdened healthcare systems, where there may be a need for resource allocation management, information about mortality risk may be helpful.

NSP2 Is Important for Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus to Trigger High Fever-Related COX-2-PGE2 Pathway in Pigs

In 2006, atypical porcine reproductive and respiratory syndrome (PRRS) caused by a highly pathogenic PRRSV (HP-PRRSV) strain broke out in China. Atypical PRRS is characterized by extremely high fever and high mortality in pigs of all ages. Prostaglandin E2 (PGE2) derived from arachidonic acid through the activation of the rate-limiting enzyme cyclooxygenase type 1/2 (COX-1/2) plays an important role in fever. Here, we showed that HP-PRRSV infection increased PGE2 production in microglia via COX-2 up-regulation depending on the activation of MEK1-ERK1/2-C/EBPβ signaling pathways. Then, we screened HP-PRRSV proteins and demonstrated that HP-PRRSV nonstructural protein 2 (NSP2) activated MEK1-ERK1/2-C/EBPβ signaling pathways by interacting with 14-3-3ζ to promote COX-2 expression, leading to PGE2 production. Furthermore, we identified that the amino acid residues 500-596 and 658-777 in HP-PRRSV NSP2 were essential to up-regulate COX-2 expression and PGE2 production. Finally, we made mutant HP-PRRS viruses with the deletion of residues 500-596 and/or 658-777, and found out that these viruses had impaired ability to up-regulate COX-2 and PGE2 production in vitro and in vivo. Importantly, pigs infected with the mutant viruses had relieved fever, clinical symptoms, and mortality. These data might help us understand the molecular mechanisms underlying the high fever and provide clues for the development of HP-PRRSV attenuated vaccines.

In a model of SAH-induced neurogenic fever, BAT thermogenesis is mediated by erythrocytes and blocked by agonism of adenosine A1 receptors

Neurogenic fever (NF) after subarachnoid hemorrhage (SAH) is a major cause of morbidity that is associated with poor outcomes and prolonged stay in the neurointensive care unit (NICU). Though SAH is a much more common cause of fever than sepsis in the NICU, it is often a diagnosis of exclusion, requiring significant effort to rule out an infectious source. NF does not respond to standard anti-pyretic medications such as COX inhibitors, and lack of good medical therapy has led to the introduction of external cooling systems that have their own associated problems. In a rodent model of SAH, we measured the effects of injecting whole blood, blood plasma, or erythrocytes on the sympathetic nerve activity to brown adipose tissue and on febrile thermogenesis. We demonstrate that following SAH the acute activation of brown adipose tissue leading to NF, is not dependent on PGE₂, that subarachnoid space injection of whole blood or erythrocytes, but not plasma alone, is sufficient to trigger brown adipose tissue thermogenesis, and that activation of adenosine A1 receptors in the CNS can block the brown adipose tissue thermogenic component contributing to NF after SAH. These findings point to a distinct thermogenic mechanism for generating NF, compared to those due to infectious causes, and will hopefully lead to new therapies.

Anthroposophic Medicine: A Short Monograph and Narrative Review-Foundations, Essential Characteristics, Scientific Basis, Safety, Effectiveness and Misconceptions

INTRODUCTION

Anthroposophic medicine is a form of integrative medicine that originated in Europe but is not well known in the US. It is comprehensive and heterogenous in scope and remains provocative and controversial in many academic circles. Assessment of the nature and potential contribution of anthroposophic medicine to whole person care and global health seems appropriate.

METHODS

Because of the heterogenous and multifaceted character of anthroposophic medicine, a narrative review format was chosen. A Health Technology Assessment of anthroposophic medicine in 2006 was reviewed and used as a starting point. A Medline search from 2006 to July 2020 was performed using various search terms and restricted to English. Books, articles, reviews and websites were assessed for clinical relevance and interest to the general reader. Abstracts of German language articles were reviewed when available. Reference lists of articles and the author's personal references were also consulted.

RESULTS

The literature on anthroposophic medicine is vast, providing new ways of thinking, a holistic view of the world, and many integrating concepts useful in medicine. In the last ∼20 years there has been a growing research base and implementation of many anthroposophical concepts in the integrated care of patients. Books and articles relevant to describing the foundations, scientific status, safety, effectiveness and criticisms of anthroposophic medicine are discussed.

DISCUSSION

An objective and comprehensive analysis of anthroposophic medicine finds it provocative, stimulating and potentially fruitful as an integrative system for whole person care, including under-recognized life processes and psychospiritual aspects of human beings. It has a legitimate, new type of scientific status as well as documented safety and effectiveness in some areas of its multimodal approach. Criticisms and controversies of anthroposophic medicine are often a result of lack of familiarity with its methods and approach and/or come from historically fixed ideas of what constitutes legitimate science.

Core warming of coronavirus disease 2019 (COVID-19) patients undergoing mechanical ventilation-A protocol for a randomized controlled pilot study

BACKGROUND

Coronavirus disease 2019 (COVID-19), caused by the virus SARS-CoV-2, is spreading rapidly across the globe, with little proven effective therapy. Fever is seen in most cases of COVID-19, at least at the initial stages of illness. Although fever is typically treated (with antipyretics or directly with ice or other mechanical means), increasing data suggest that fever is a protective adaptive response that facilitates recovery from infectious illness.

OBJECTIVE

To describe a randomized controlled pilot study of core warming patients with COVID-19 undergoing mechanical ventilation.

METHODS

This prospective single-site randomized controlled pilot study will enroll 20 patients undergoing mechanical ventilation for respiratory failure due to COVID-19. Patients will be randomized 1:1 to standard-of-care or to receive core warming via an esophageal heat exchanger commonly utilized in critical care and surgical patients. The primary outcome is patient viral load measured by lower respiratory tract sample. Secondary outcomes include severity of acute respiratory distress syndrome (as measured by PaO2/FiO2 ratio) 24, 48, and 72 hours after initiation of treatment, hospital and intensive care unit length of stay, duration of mechanical ventilation, and 30-day mortality.

RESULTS

Resulting data will provide effect size estimates to guide a definitive multi-center randomized clinical trial. ClinicalTrials.gov registration number: NCT04426344.

CONCLUSIONS

With growing data to support clinical benefits of elevated temperature in infectious illness, this study will provide data to guide further understanding of the role of active temperature management in COVID-19 treatment and provide effect size estimates to power larger studies.

COVID-19 multidisciplinary high dependency unit: the Milan model

COVID-19 is a complex and heterogeneous disease. The pathogenesis and the complications of the disease are not fully elucidated, and increasing evidence shows that SARS-CoV-2 causes a systemic inflammatory disease rather than a pulmonary disease. The management of hospitalized patients in COVID-19 dedicated units is advisable for segregation purpose as well as for infection control. In this article we present the standard operating procedures of our COVID-19 high dependency unit of the Policlinico Hospital, in Milan. Our high dependency unit is based on a multidisciplinary approach. We think that the multidisciplinary involvement of several figures can better identify treatable traits of COVID-19 disease, early identify patients who can quickly deteriorate, particularly patients with multiple comorbidities, and better manage complications related to off-label treatments. Although no generalizable to other hospitals and different healthcare settings, we think that our experience and our point of view can be helpful for countries and hospitals that are now starting to face the COVID-19 outbreak.

Moderate Fever Cycles as a Potential Mechanism to Protect the Respiratory System in COVID-19 Patients

Mortality in COVID-19 patients predominantly results from an acute respiratory distress syndrome (ARDS), in which lungs alveolar cells undergo programmed cell death. Mortality in a sepsis-induced ARDS rat model is reduced by adenovirus over-expression of the HSP70 chaperone. A natural rise of body temperature during mild fever can naturally accumulate high cellular levels of HSP70 that can arrest apoptosis and protect alveolar lung cells from inflammatory damages. However, beyond 1-2 h of fever, no HSP70 is being further produced and a decreased in body temperature required to the restore cell's ability to produce more HSP70 in a subsequent fever cycle. We suggest that antipyretics may be beneficial in COVID-19 patients subsequent to several hours of mild (<38.8°C) advantageous fever, allowing lung cells to accumulate protective HSP70 against damages from the inflammatory response to the virus SARS-CoV-2. With age, the ability to develop fever and accumulate HSP70 decreases. This could be ameliorated, when advisable to do so, by thermotherapies and/or physical training.

Febrile temperature change modulates CD4 T cell differentiation via a TRPV channel-regulated Notch-dependent pathway

Fever is a conserved and prominent response to infection. Yet, the issue of how CD4 T cell responses are modulated if they occur at fever temperatures remains poorly addressed. We have examined the priming of naive CD4 T cells in vitro at fever temperatures, and we report notable fever-mediated modulation of their cytokine commitment. When naive CD4 T cells were primed by plate-bound anti-CD3 and anti-CD28 monoclonal antibodies at moderate fever temperature (39 °C), they enhanced commitment to IL4/5/13 (Th2) and away from IFNg (Th1). This was accompanied by up-regulation of the Th2-relevant transcription factor GATA3 and reduction in the Th1-relevant transcription factor Tbet. Fever sensing by CD4 T cells involved transient receptor potential vanilloid cation channels (TRPVs) since TRPV1/TRPV4 antagonism blocked the febrile Th2 switch, while TRPV1 agonists mediated a Th2 switch at 37 °C. The febrile Th2 switch was IL4 independent, but a γ-secretase inhibitor abrogated it, and it was not found in Notch1-null CD4 T cells, identifying the Notch pathway as a major mediator. However, when naive CD4 T cells were primed via antigen and dendritic cells (DCs) at fever temperatures, the Th2 switch was abrogated via increased production of IL12 from DCs at fever temperatures. Thus, immune cells directly sense fever temperatures with likely complex physiological consequences.

The Use of Core Warming as a Treatment for Coronavirus Disease 2019 (COVID-19): an Initial Mathematical Model

Background: Increasing data suggest that elevated body temperature may be helpful in resolving a variety of diseases, including sepsis, acute respiratory distress syndrome (ARDS), and viral illnesses. SARS-CoV-2, which causes coronavirus disease 2019 (COVID-19), may be more temperature sensitive than other coronaviruses, particularly with respect to the binding affinity of its viral entry via the ACE2 receptor. A mechanical provision of elevated temperature focused in a body region of high viral activity in patients undergoing mechanical ventilation may offer a therapeutic option that avoids arrhythmias seen with some pharmaceutical treatments. We investigated the potential to actively provide core warming to the lungs of patients with a commercially available heat transfer device via mathematical modeling, and examine the influence of blood perfusion on temperature using this approach. Methods: Using the software Comsol Multiphysics, we modeled and simulated heat transfer in the body from an intraesophageal warming device, taking into account the airflow from patient ventilation. The simulation was focused on heat transfer and warming of the lungs and performed on a simplified geometry of an adult human body and airway from the pharynx to the lungs. Results: The simulations were run over a range of values for blood perfusion rate, which was a parameter expected to have high influence in overall heat transfer, since the heat capacity and density remain almost constant. The simulation results show a temperature distribution which agrees with the expected clinical experience, with the skin surface at a lower temperature than the rest of the body due to convective cooling in a typical hospital environment. The highest temperature in this case is the device warming water temperature, and that heat diffuses by conduction to the nearby tissues, including the air flowing in the airways. At the range of blood perfusion investigated, maximum lung temperature ranged from 37.6°C to 38.6°C. Conclusions: The provision of core warming via commercially available technology currently utilized in the intensive care unit, emergency department, and operating room can increase regional temperature of lung tissue and airway passages. This warming may offer an innovative approach to treating infectious diseases from viral illnesses such as COVID-19, while avoiding the arrhythmogenic complications of currently used pharmaceutical treatments.

Intermittent binge-like ethanol exposure during adolescence attenuates the febrile response by reducing brown adipose tissue thermogenesis in rats

Ethanol (EtOH) consumption is a primary health risk worldwide, which generally starts during adolescence in a binge pattern (i.e., the episodic consumption of high amounts). Binge EtOH consumption can lead to modifications of the innate and adaptive immune responses, including fever. The present study evaluated the febrile response that was induced by lipopolysaccharide (LPS) and prostaglandins E₂ (PGE₂) and the mechanisms of thermoregulation in adolescent rats that were exposed to EtOH in a binge-like pattern. Male Wistar rats were treated with an intraperitoneal (i.p.) injection of EtOH or saline on postnatal days (PND) 25, 26, 29, 30, 33, 34, 37, and 38. On PND 51, they received a pyrogenic challenge with LPS (i.p.) or PGE₂ (intracerebroventricular) to induce a febrile response. Interscapular brown adipose tissue (BAT) mass and uncoupling protein (UCP) activity in isolated mitochondria were evaluated on PND 51. The rats were then subjected to cold challenges to analyze adaptive thermogenesis. Intermittent EtOH exposure during adolescence impaired the LPS- and PGE₂-induced febrile response 12 days after the end of EtOH exposure. Ethanol exposure decreased interscapular BAT mass, oxygen consumption, and UCP activity in isolated mitochondria, resulting in an impairment in thermogenesis at 5 °C. No morphological changes in BAT were observed. These findings indicate that binge-like EtOH exposure during adolescence impairs thermoregulation by reducing BAT mass and function. This reduction may last for a prolonged period of time after the cessation of EtOH exposure and may affect both cold defenses and the febrile response during the development of infectious diseases.

The Effects of Abnormal Body Temperature on the Prognosis of Patients with Septic Shock

We aimed to use temperature and the area under temperature curve to represent the severity of abnormal body temperature of patients with septic shock and to observe their impact on the prognosis. Five hundred twenty-eight adult patients with septic shock admitted to intensive care unit (ICU) were analyzed. Within the first 24 hours and throughout the period in ICU, the maximum temperature (24hT_max, T_max), lowest temperature (24hT_min, T_min), and the temperature range (24hT_max-min, T_max-min) were aggregated. Patients were divided into the survival group and the death group. Binary logistic regression was used to assess the relationship between body temperature aberrations and survival. The following risk factors of death in 21 days were identified: T_max (odds ratio [OR] 2.967, 95% confidence interval [CI] 1.626-5.414, p < 0.001), T_min (OR 0.337, 95% CI 0.143-0.794, p = 0.013), and T_max-min (OR 3.259, 95% CI 1.847-5.749, p < 0.001). This is an observational study, so one can infer association but not causation. Therefore, we infer that abnormal body temperature is associated with an adverse prognosis in patients with septic shock.

Antipyretic drugs in patients with fever and infection: literature review

BACKGROUND

antipyretic drugs are routinely administered to febrile patients with infection in secondary care. However, the use of antipyretics to suppress fever during infection remains a controversial topic within the literature. It is argued that fever suppression may interfere with the body's natural defence mechanisms, and may worsen patient outcomes.

METHOD

a literature review was undertaken to determine whether the administration of antipyretic drugs to adult patients with infection and fever, in secondary care, improves or worsens patient outcomes.

RESULTS

contrasting results were reported; two studies demonstrated improved patient outcomes following antipyretic administration, while several studies demonstrated increased mortality risk associated with antipyretics and/or demonstrated fever's benefits during infection. Results also demonstrated that health professionals continue to view fever as deleterious.

CONCLUSION

the evidence does not currently support routine antipyretic administration. Considering patients' comorbidities and symptoms of their underlying illness will promote safe, evidence-based and appropriate administration of antipyretics.

The Contribution of Complementary and Alternative Medicine to Reduce Antibiotic Use: A Narrative Review of Health Concepts, Prevention, and Treatment Strategies

AIM

The aim of this narrative review was to explore the potential contributions of CAM to reduce antibiotic use.

METHODS

We searched PubMed, Embase, and Cochrane Database of Systematic Reviews with a specific, limited set of search terms and collected input from a group of expert CAM researchers to answer the question: What is known about the contribution of CAM health and health promotion concepts, infection prevention, and infection treatment strategies to reduce antibiotic use? Results. The worldview-related CAM health concepts enable health promotion oriented infection prevention and treatment aimed at strengthening or supporting the self-regulating ability of the human organism to cope with diseases. There is some evidence that the CAM concepts of health (promotion) are in agreement with current conceptualization of health and that doctors who practice both CAM and conventional medicine prescribe less antibiotics, although selection bias of the presented studies cannot be ruled out. There is some evidence that prevention and some treatment strategies are effective and safe. Many CAM treatment strategies are promising but overall lack high quality evidence.

CONCLUSIONS

CAM prevention and treatment strategies may contribute to reducing antibiotic use, but more rigorous research is necessary to provide high quality evidence of (cost-)effectiveness.

[Fever in the critically ill : To treat or not to treat]

Fever, arbitrarily defined as a core body temperature >38.3 °C, is present in 20-70 % of intensive care unit patients. Fever caused by infections is a physiologic reset of the thermostatic set-point and is associated with beneficial consequences, but may have negative sequelae with temperatures >39.5 °C. Fever of non-infectious and neurologic origin affects about 50 % of patients with elevated body temperature, presents as a pathologic loss of thermoregulation, and may be associated with untoward side effects at temperatures above 38.5-39.0 °C. Cooling can be achieved by physical and pharmacologic means. Evidence-based recommendations are not available. The indication for a cooling therapy can only be based on the physiologic reserve and the neurologic, hemodynamic, and respiratory state. The temperature should be lowered to the normothermic range. Hyperthermia syndromes require immediate physical cooling (and dantrolen when indicated).

[Antipyretics in intensive care patients]

BACKGROUND

Antipyretics are among the most widely prescribed drugs in German hospitals. Despite this widespread use, their role for treatment of critically ill patients still remains unclear. In particular, the questionable positive effects of reducing fever are discussed.

OBJECTIVES

In this review we aimed to summarize and discuss current study results covering the use of antipyretics in critically ill patients. Suspected effects with regard to fever reduction and lethality should be considered.

MATERIALS AND METHODS

A selective literature search was carried out in the PubMed database. We reviewed the bibliographies of all work considered relevant.

RESULTS

There are only a few studies on the use of antipyretics in intensive care patients, which are difficult to compare systematically due to different designs, protocols and endpoints. All in all, the decrease in temperature was very low (0.3 °C) and showed even adverse effects on 28-days mortality in sepsis. In patients with sepsis and ASS medication, a decreased mortality has been shown in retrospective analysis.

CONCLUSIONS

The benefit of fever control using antipyretics in intensive care patients with regard to endpoints like lethality remains unclear. Randomized controlled trials with suitable protocols and endpoints are needed to provide a solid base for development of guidelines.

Early diagnosis using canonical discriminant analysis of innate immune receptor gene expression profiles in a murine infectious or sterile systemic inflammation model

BACKGROUND

Infection in patients with systemic inflammation is difficult to diagnose with a single biomarker. We aimed to clarify the time course of change in the gene expression profile of innate immune receptors in infectious or sterile inflammation and to establish an early diagnostic method using canonical discriminant analysis (CDA) of the gene expression profile.

METHODS

To compare infectious and sterile inflammation, we used cecal ligation and puncture (CLP) and 20% full-thickness burn injury (Burn) models. C57BL/6 mice underwent sham treatment (n = 9 × three groups), CLP (n = 12 × three groups), or Burn (n = 12 × three groups) injury. Mice were killed at 6, 12, and 24 hours after injury, and total RNA was extracted from whole blood. We used quantitative real-time polymerase chain reaction to investigate gene expression of innate immune receptors Toll-like receptor 2 (TLR2), TLR4, TLR9, NLRP3 (nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3), and retinoic acid-inducible gene I. To evaluate all gene expression together as patterns, each value was standardized, and CDA was performed at each time point.

RESULTS

Gene expression of TLR2 and TLR4 was already significantly increased in both CLP and Burn compared with sham mice at 6 hours after injury (p < 0.05). Gene expression of TLR9 was significantly decreased in CLP compared with sham and Burn mice at 12 hours and 24 hours after injury (p < 0.05) but not at 6 hours. Gene expression of NLRP3 was significantly increased in CLP and Burn compared with sham mice at 6 hours and 24 hours after injury (p < 0.05). In the CDA, each group showed distinctive gene expression patterns at only 6 hours after injury. Each group was clearly classified, and the classification error rates were 0% at all of the time points.

CONCLUSIONS

Canonical discriminant analysis of the gene expression profile of innate immune receptors could be a novel approach for diagnosing the pathophysiology of complicated systemic inflammation from the early stage of injury.

Affective immunology: where emotions and the immune response converge

Affect and emotion are defined as “an essential part of the process of an organism's interaction with stimuli.” Similar to affect, the immune response is the “tool” the body uses to interact with the external environment. Thanks to the emotional and immunological response, we learn to distinguish between what we like and what we do not like, to counteract a broad range of challenges, and to adjust to the environment we are living in. Recent compelling evidence has shown that the emotional and immunological systems share more than a similarity of functions. This review article will discuss the crosstalk between these two systems and the need for a new scientific area of research called affective immunology. Research in this field will allow a better understanding and appreciation of the immunological basis of mental disorders and the emotional side of immune diseases.

Derivation and validation of a universal vital assessment (UVA) score: a tool for predicting mortality in adult hospitalised patients in sub-Saharan Africa

Background

Critical illness is a leading cause of morbidity and mortality in sub-Saharan Africa (SSA). Identifying patients with the highest risk of death could help with resource allocation and clinical decision making. Accordingly, we derived and validated a universal vital assessment (UVA) score for use in SSA.

Methods

We pooled data from hospital-based cohort studies conducted in six countries in SSA spanning the years 2009–2015. We derived and internally validated a UVA score using decision trees and linear regression and compared its performance with the modified early warning score (MEWS) and the quick sepsis-related organ failure assessment (qSOFA) score.

Results

Of 5573 patients included in the analysis, 2829 (50.8%) were female, the median (IQR) age was 36 (27–49) years, 2122 (38.1%) were HIV-infected and 996 (17.3%) died in-hospital. The UVA score included points for temperature, heart and respiratory rates, systolic blood pressure, oxygen saturation, Glasgow Coma Scale score and HIV serostatus, and had an area under the receiver operating characteristic curve (AUC) of 0.77 (95% CI 0.75 to 0.79), which outperformed MEWS (AUC 0.70 (95% CI 0.67 to 0.71)) and qSOFA (AUC 0.69 (95% CI 0.67 to 0.72)).

Conclusion

We identified predictors of in-hospital mortality irrespective of the underlying condition(s) in a large population of hospitalised patients in SSA and derived and internally validated a UVA score to assist clinicians in risk-stratifying patients for in-hospital mortality. The UVA score could help improve patient triage in resource-limited environments and serve as a standard for mortality risk in future studies.

Effect of Antipyretic Therapy on Mortality in Critically Ill Patients with Sepsis Receiving Mechanical Ventilation Treatment

Purpose. The study aimed to investigate the effectiveness of antipyretic therapy on mortality in critically ill patients with sepsis requiring mechanical ventilation. Methods. In this study, we employed the multiparameter intelligent monitoring in intensive care II (MIMIC-II) database (version 2.6). All patients meeting the criteria for sepsis and also receiving mechanical ventilation treatment were included for analysis, all of whom suffer from fever or hyperthermia. Logistic regression model and R language (R version 3.2.3 2015-12-10) were used to explore the association of antipyretic therapy and mortality risk in critically ill patients with sepsis receiving mechanical ventilation treatment. Results. A total of 8,711 patients with mechanical ventilator were included in our analysis, and 1523 patients died. We did not find any significant difference in the proportion of patients receiving antipyretic medication between survivors and nonsurvivors (7.9% versus 7.4%, p = 0.49). External cooling was associated with increased risk of death (13.5% versus 9.5%, p < 0.001). In our regression model, antipyretic therapy was positively associated with mortality risk (odds ratio [OR]: 1.41, 95% CI: 1.20–1.66, p < 0.001). Conclusions. The use of antipyretic therapy is associated with increased risk of mortality in septic ICU patients requiring mechanical ventilation. External cooling may even be deleterious.

Affective immunology: where emotions and the immune response converge

Affect and emotion are defined as "an essential part of the process of an organism's interaction with stimuli." Similar to affect, the immune response is the "tool" the body uses to interact with the external environment. Thanks to the emotional and immunological response, we learn to distinguish between what we like and what we do not like, to counteract a broad range of challenges, and to adjust to the environment we are living in. Recent compelling evidence has shown that the emotional and immunological systems share more than a similarity of functions. This review article will discuss the crosstalk between these two systems and the need for a new scientific area of research called affective immunology. Research in this field will allow a better understanding and appreciation of the immunological basis of mental disorders and the emotional side of immune diseases.

Risk factors and familial clustering for fever 7-10days after the first dose of measles vaccines

BACKGROUND

Seven to ten days after a first dose of a measles-containing vaccine (MCV; i.e., MMR or MMRV), children have elevated fever risk which can be associated with febrile seizures. This study investigated individual and familial factors associated with fever 7-10days after MCV.

METHODS

Retrospective cohort study among children who were <36months of age at receipt of MCV in six sites of the Vaccine Safety Datalink from 1/1/2000 to 12/31/2012. We evaluated medically-attended clinic or emergency department visits with a code for fever 7-10days after any MCV ("MCV- associated"). We evaluated factors associated with MCV-associated fever using χ² and multivariable logistic regression analyses.

RESULTS

Among 946,806 children vaccinated with MCV, we identified 7480 (0.8%) MCV-associated fever visits. Compared with children without fever after MCV, children with MCV-associated fever were more likely to have received MMRV than MMR (OR 1.3 95% CI 1.2, 1.5), have had medically attended fever both following previous vaccines (OR 1.3 95% CI 1.1, 1.6) and at any other previous time (OR 1.7 95% CI 1.6, 1.8), have had at least 1 prior seizure (OR 2.2 95% CI 1.7, 2.7), and have had >3 medical visits within the 6months before MCV (OR 1.7 95% CI 1.6, 1.8). In families with multiple MCV-immunized children, after adjusting for healthcare seeking behavior care for fever, those whose siblings had MCV-associated fever were more likely to also have MCV-associated fever (OR 3.5 95% CI 2.5, 4.8).

DISCUSSION

Children who received MMRV vaccine or who had prior medically-attended fevers and seizures during the first year of life had increased risk of fever after a first dose of measles vaccine. After adjusting for familial propensity to seek care, MCV-associated fever still clustered within families, suggesting a possible genetic basis for susceptibility to developing fever due to measles vaccines.

Fever of Unknown Origin in Childhood

Childhood fever of unknown origin (FUO) is most often related to an underlying infection but can also be associated with a variety of neoplastic, rheumatologic, and inflammatory conditions. Repeated, focused reviews of patient history and physical examination are often helpful in suggesting a likely diagnosis. Diagnostic workup should be staged, usually leaving invasive testing for last. Advances in molecular genetic techniques have increased the importance of these assays in the diagnosis of FUO in children.

Behavioral fever in ectothermic vertebrates

Fever is an evolutionary conserved defense mechanism which is present in both endothermic and ectothermic vertebrates. Ectotherms in response to infection can increase their body temperature by moving to warmer places. This process is known as behavioral fever. In this review, we summarize the current knowledge on the mechanisms of induction of fever in mammals. We further discuss the evolutionary conserved mechanisms existing between fever of mammals and behavioral fever of ectothermic vertebrates. Finally, the experimental evidences supporting an adaptive value of behavioral fever expressed by ectothermic vertebrates are summarized.

Autophagy--A free meal in sickness-associated anorexia

Activation of the immune system is metabolically costly, yet a hallmark of an infection is a reduction in appetite with a subsequent reduction in metabolite provision. What is the functional value of decreasing nutrient intake when an infection imposes large demands on metabolic parameters? Here, we propose that sickness-associated anorexia (SAA) upregulates the ancient process of autophagy systemically, thereby profoundly controlling not only immune- but also nonimmune-competent cells. This allows an advanced impact on the resolution of an infection through direct pathogen killing, enhancement of epitope presentation and the contribution toward the clearance of noxious factors. By rendering a 'free meal,' autophagy is thus most fundamentally harnessed during an anorexic response in order to promote both host tolerance and resistance. These findings strongly suggest a reassessment of numerous SAA-related clinical applications and a re-evaluation of current efforts in patient care.

Outcome of severe infections in afebrile neutropenic cancer patients

BACKGROUND

In some neutropenic cancer patients fever may be absent despite microbiologically and/or clinically confirmed infection. We hypothesized that afebrile neutropenic cancer patients with severe infections have worse outcome as compared to cancer patients with febrile neutropenia.

PATIENTS AND METHODS

We retrospectively analyzed all adult cancer patients with chemotherapy-induced neutropenia and severe infection, who were admitted to the Intensive Care Unit at our cancer center between 2000 and 2011. The outcome of interest was 30-day in-hospital mortality rate. Association between the febrile status and in-hospital mortality rate was evaluated by the Fisher's exact test.

RESULTS

We identified 69 episodes of severe neutropenic infections in 65 cancer patients. Among these, 9 (13%) episodes were afebrile. Patients with afebrile neutropenic infection presented with hypotension, severe fatigue with inappetence, shaking chills, altered mental state or cough and all of them eventually deteriorated to severe sepsis or septic shock. Overall 30-day in-hospital mortality rate was 55.1%. Patients with afebrile neutropenic infection had a trend for a higher 30-day in-hospital mortality rate as compared to patients with febrile neutropenic infection (78% vs. 52%, p = 0.17).

CONCLUSIONS

Afebrile cancer patients with chemotherapy-induced neutropenia and severe infections might have worse outcome as compared to cancer patients with febrile neutropenia. Patients should be informed that severe neutropenic infection without fever can occasionally occur during cancer treatment with chemotherapy.

Fever: Views in Anthroposophic Medicine and Their Scientific Validity

Objective. To conduct a scoping review to characterize how fever is viewed in anthroposophic medicine (AM) and discuss the scientific validity of these views. Methods. Systematic searches were run in Medline, Embase, CAMbase, and Google Scholar. Material from anthroposophic medical textbooks and articles was also used. Data was extracted and interpreted. Results. Most of the anthroposophic literature on this subject is in the German language. Anthroposophic physicians hold a beneficial view on fever, rarely suppress fever with antipyretics, and often use complementary means of alleviating discomfort. In AM, fever is considered to have the following potential benefits: promoting more complete recovery; preventing infection recurrences and atopic diseases; providing a unique opportunity for caregivers to provide loving care; facilitating individual development and resilience; protecting against cancer and boosting the anticancer effects of mistletoe products. These views are discussed with regard to the available scientific data. Conclusion. AM postulates that fever can be of short-term and long-term benefit in several ways; many of these opinions have become evidence-based (though still often not practiced) while others still need empirical studies to be validated, refuted, or modified.

The pathophysiological basis and consequences of fever

There are numerous causes of a raised core temperature. A fever occurring in sepsis may be associated with a survival benefit. However, this is not the case for non-infective triggers. Where heat generation exceeds heat loss and the core temperature rises above that set by the hypothalamus, a combination of cellular, local, organ-specific, and systemic effects occurs and puts the individual at risk of both short-term and long-term dysfunction which, if severe or sustained, may lead to death. This narrative review is part of a series that will outline the pathophysiology of pyrogenic and non-pyrogenic fever, concentrating primarily on the pathophysiology of non-septic causes.

Faut-il contrôler la fièvre dans les infections sévères ?

Le contrôle de la fièvre lors des sepsis graves est couramment utilisé en réanimation, respectivement dans 66 et 70 % des états septiques graves et des chocs septiques. Pourtant, les preuves formelles quant au bénéfice d’une telle stratégie manquent. On peut s’interroger à la lumière de travaux expérimentaux parfois anciens et d’études observationnelles plus récentes des risques d’un contrôle sur le cours évolutif de l’infection, le devenir du patient, ainsi que sur l’innocuité des traitements appliqués pour obtenir le contrôle. Néanmoins, dans certaines situations, la fièvre peut être délétère, en lien avec une consommation en oxygène (O₂) accrue et le risque d’ischémie tissulaire et/ou une réaction inflammatoire focale exacerbée. Chez des patients septiques, le contrôle de la fièvre fait appel à des moyens physiques (refroidissement externe et/ou interne) et/ou pharmacologiques (essentiellement le paracétamol et/ou des anti-inflammatoires non stéroïdiens). Malgré les incertitudes quant au bénéfice ou non à contrôler la température, il faut certainement s’affranchir des températures extrêmes (hypoou hyperthermie) et évaluer individuellement le rapport bénéfice/risque.

Fever and sickness behavior: Friend or foe?

Fever has been recognized as an important symptom of disease since ancient times. For many years, fever was treated as a putative life-threatening phenomenon. More recently, it has been recognized as an important part of the body's defense mechanisms; indeed at times it has even been used as a therapeutic agent. The knowledge of the functional role of the central nervous system in the genesis of fever has greatly improved over the last decade. It is clear that the febrile process, which develops in the sick individual, is just one of many brain-controlled sickness symptoms. Not only will the sick individual appear "feverish" but they may also display a range of behavioral changes, such as anorexia, fatigue, loss of interest in usual daily activities, social withdrawal, listlessness or malaise, hyperalgesia, sleep disturbances and cognitive dysfunction, collectively termed "sickness behavior". In this review we consider the issue of whether fever and sickness behaviors are friend or foe during: a critical illness, the common cold or influenza, in pregnancy and in the newborn. Deciding whether these sickness responses are beneficial or harmful will very much shape our approach to the use of antipyretics during illness.

Targeted temperature management in intensive care - Do we let nature take its course?

Should we aim to intervene and control fever in the critically ill patient? The answer is not straightforward and there is certainly no universal agreement on the subject. This article aims to discuss whether we should over-ride nature and disallow it to take it's course, particularly where it appears that this evolutionary response to invading pathogens is actually becoming harmful to the patient. Also discussed here are the physiology of temperature control and the scope of our current understanding of the impact of fever in patients manifesting systemic inflammatory response syndrome (SIRS) and sepsis in ICU, the possible interventions to combat fever (both physical and pharmacological) and the evidence for anti-pyretic drug therapy. The final section examines the potential role of targeted temperature management in the management of sepsis / SIRS in the critically ill.