Pyrexia: aetiology in the ICU

Accuracy, precision and diagnostic accuracy of oral thermometry in pediatric patients

PURPOSE

To determine the accuracy and precision of oral thermometry in pediatric patients, along with its sensitivity and specificity for detecting fever and hypothermia, with rectal thermometry as reference standard.

DESIGN AND METHODS

This method-comparison study enrolled patients aged between 6 and 17 years, admitted to the surgical ward during a 21-month period. KD-2150 and IVAC Temp Plus II were used for oral and rectal temperature measurements respectively. Fever and hypothermia were defined as core temperature ≥38.0 °C and ≤ 35.9 °C respectively. Accuracy and precision of oral thermometry were determined by the Bland-Altman method. Sensitivity, specificity, positive and negative predictive value, and correct classification of oral temperature cutoffs for detecting fever and hypothermia were calculated.

RESULTS

Based on power analysis, 100 pediatric patients were enrolled. The mean difference between oral and rectal temperatures was -0.34 °C, with 95 % limits of agreement ranging between -0.52 and -0.16. Sensitivity and specificity of oral thermometry for detecting fever were 0.50 and 1.0 respectively; its sensitivity and specificity for detecting hypothermia were 1.0 and 0.88 respectively. The oral temperature value of 37.6 °C provided excellent sensitivity for detecting fever, while the value of 35.7 °C provided optimal sensitivity and specificity for detecting hypothermia.

CONCLUSIONS

Oral thermometry had low sensitivity for detecting fever and suboptimal specificity for detecting hypothermia; thus, temperature values <38.0 °C and <36.0 °C cannot exclude fever and confirm hypothermia respectively with high certainty.

PRACTICE IMPLICATIONS

Diagnostic accuracy of oral thermometry can be improved by the use of oral temperature thresholds <38.0 °C for detecting fever and <35.9 °C for detecting hypothermia.

Fever and infections in surgical intensive care: an American Association for the Surgery of Trauma Critical Care Committee clinical consensus document

The evaluation and workup of fever and the use of antibiotics to treat infections is part of daily practice in the surgical intensive care unit (ICU). Fever can be infectious or non-infectious; it is important to distinguish between the two entities wherever possible. The evidence is growing for shortening the duration of antibiotic treatment of common infections. The purpose of this clinical consensus document, created by the American Association for the Surgery of Trauma Critical Care Committee, is to synthesize the available evidence, and to provide practical recommendations. We discuss the evaluation of fever, the indications to obtain cultures including urine, blood, and respiratory specimens for diagnosis of infections, the use of procalcitonin, and the decision to initiate empiric antibiotics. We then describe the treatment of common infections, specifically ventilator-associated pneumonia, catheter-associated urinary infection, catheter-related bloodstream infection, bacteremia, surgical site infection, intra-abdominal infection, ventriculitis, and necrotizing soft tissue infection.

Overlapping Physiologic Signs of Sepsis and Paroxysmal Sympathetic Hyperactivity After Traumatic Brain Injury: Exploring A Clinical Conundrum

BACKGROUND

Paroxysmal sympathetic hyperactivity (PSH) occurs in a subset of patients with traumatic brain injury (TBI) and is associated with worse outcomes. Sepsis is also associated with worse outcomes after TBI and shares several physiologic features with PSH, potentially creating diagnostic confusion and suboptimal management of each. This is the first study to directly investigate the interaction between PSH and infection using robust diagnostic criteria.

METHODS

We performed a retrospective cohort study of patients with TBI admitted to a level I trauma center intensive care unit with hospital length of stay of at least 2 weeks. From January 2016 to July 2018, 77 patients diagnosed with PSH were 1:1 matched by age and Glasgow Coma Scale to 77 patients without PSH. Trauma infectious diseases subspecialists prospectively documented assessments corroborating diagnoses of infection. Extracted data including incidence, timing, classification, and anatomical source of infections were compared according to PSH diagnosis. We also evaluated daily PSH clinical feature severity scores and systemic inflammatory response syndrome (SIRS) criteria and compared values for patients with and without confirmed infection, stratified by PSH diagnosis.

RESULTS

During the first 2 weeks of hospitalization, there were no differences in rates of suspected (62%) nor confirmed (48%) infection between patients with PSH and controls. Specific treatments for PSH were initiated on median hospital day 7 and for confirmed infections on median hospital day 8. SIRS criteria could identify infection only in patients who were not diagnosed with PSH.

CONCLUSIONS

In the presence of brain injury-induced autonomic nervous system dysregulation, the initiation and continuation of antimicrobial therapy is a challenging clinical decision, as standard physiologic markers of sepsis do not distinguish infected from noninfected patients with PSH, and these entities often present around the same time. Clinicians should be aware that PSH is a potential driver of SIRS, and familiarity with its diagnostic criteria as proposed by the PSH assessment measure is important. Management by a multidisciplinary team attentive to these issues may reduce rates of inappropriate antibiotic usage and misdiagnoses.

Metagenomic next-generation sequencing of plasma cell-free DNA improves the early diagnosis of suspected infections

BACKGROUND

Metagenomic next-generation sequencing (mNGS) could improve the diagnosed efficiency of pathogens in bloodstream infections or sepsis. Little is known about the clinical impact of mNGS test when used for the early diagnosis of suspected infections. Herein, our main objective was to assess the clinical efficacy of utilizing blood samples to perform mNGS for early diagnosis of suspected infections, as well as to evaluate its potential in guiding antimicrobial therapy decisions.

METHODS

In this study, 212 adult hospitalized patients who underwent blood mNGS test in the early stage of suspected infections were enrolled. Diagnostic efficacy of mNGS test and blood culture was compared, and the clinical impact of mNGS on clinical care was analyzed.

RESULTS

In our study, the total detection rate of blood mNGS was significantly higher than that of culture method (74.4% vs. 12.1%, P < 0.001) in the paired mNGS test and blood culture. Blood stream infection (107, 67.3%) comprised the largest component of all the diseases in our patients, and the detection rate of single blood sample subgroup was similar with that of multiple type of samples subgroup. Among the 187 patients complained with fever, there was no difference in the diagnostic efficacy of mNGS when blood specimens or additional other specimens were used in cases presenting only with fever. While, when patients had other symptoms except fever, the performance of mNGS was superior in cases with specimens of suspected infected sites and blood collected at the same time. Guided by mNGS results, therapeutic regimens for 70.3% cases (149/212) were changed, and the average hospitalized days were significantly shortened in cases with the earlier sampling time of admission.

CONCLUSION

In this study, we emphasized the importance of blood mNGS in early infectious patients with mild and non-specific symptoms. Blood mNGS can be used as a supplement to conventional laboratory examination, and should be performed as soon as possible to guide clinicians to perform appropriate anti-infection treatment timely and effectively. Additionally, combining the contemporaneous samples from suspected infection sites could improve disease diagnosis and prognoses. Further research needs to be better validated in large-scale clinical trials to optimize diagnostic protocol, and the cost-utility analysis should be performed.

Trauma-related thyroid storm in adolescents: A case report

Background

Because of a scant report, it is little known that thyroid storms can occur after trauma, even in adolescence. Significantly, this increases the risk of delaying diagnosis resulting in life-threatening.

Case Presentation

A 13-year-old girl was admitted to the emergency department after a traffic accident. Despite receiving comprehensive trauma care, the patient developed hyperthermia and tachycardia that did not respond to temperature management therapy. On the 10th day of her admission, she was diagnosed with a thyroid storm. Treatment for thyroid storm was initiated; thereby, her condition was totally improved.

Conclusion

We experienced a case of an adolescent girl, who developed a thyroid storm during the treatment of trauma and could save her life. Clinicians should consider thyroid storm in post-traumatic hyperthermia and tachycardia patients, even in children.

Diketopyrrolopyrrole-based fluorescent probe for visualizing over-expressed carboxylesterase in fever via ratiometric imaging

Fever is the result of inflammation and the innate self-defense response of organisms, can cause abnormal changes in the activity of many enzymes in organisms, including the important carboxylesterase (CE). Monitoring the activity changes of CE in vivo during a fever will help to understand heat-related pathological mechanisms. In this paper, we designed diketopyrrolopyrrole-based ratiometric fluorescent probes DPP-FBC-P and DPP-FBO-P containing alkyl chain and diethylene glycol monomethyl ether chain respective for detection of CE. Both probes could realized fast response to CE and displayed good selectivity and high sensitivity. Compared with DPP-FBO-P, DPP-FBC-P had better biocompatibility, larger signal to noise ratio (225-fold vs 125-fold) and lower detection limit (1.6 × 10-5 U/mL vs 4.2 × 10-5 U/mL). Moreover, the probe DPP-FBC-P had been successfully applied to image the endogenous CE in HepG2 cells and solid tumors, and also visualized the over expressed CE in fever cells. Most importantly, the changes of CE level in the liver of fever mice model induced by LPS were monitored with the assistance of DPP-FBC-Pvia dual channel ratio imaging for the first time. In addition, fluorescence color signal in solution was captured by smart phone, and the linear relationship between RGB ratio (G/R) and CE concentration was established. This work will provide a potential approach for investigating the physiological and pathological processes of heat related diseases.

Low body temperature and mortality in critically ill patients with coronary heart disease: a retrospective analysis from MIMIC-IV database

BACKGROUND

This study was aimed to investigate the correlation between low body temperature and outcomes in critically ill patients with coronary heart disease (CHD).

METHODS

Participants from the Medical Information Mart for Intensive Care (MIMIC)-IV were divided into three groups (≤ 36.5 ℃, 36.6-37.4 ℃, ≥ 37.5 ℃) in accordance with body temperature measured orally in ICU. In-hospital, 28-day and 90-day mortality were the major outcomes. Multivariable Cox regression, decision curve analysis (DCA), restricted cubic splines (RCS), Kaplan-Meier curves (with or without propensity score matching), and subgroup analyses were used to investigate the association between body temperature and outcomes.

RESULTS

A total of 8577 patients (65% men) were included. The in-hospital, 28-day, 90-day, and 1-year overall mortality rate were 10.9%, 16.7%, 21.5%, and 30.4%, respectively. Multivariable Cox proportional hazards regression analyses indicated that patients with hypothermia compared to the patients with normothermia were at higher risk of in-hospital [adjusted hazard ratios (HR) 1.23, 95% confidence interval (CI) 1.01-1.49], 28-day (1.38, 1.19-1.61), and 90-day (1.36, 1.19-1.56) overall mortality. For every 1 ℃ decrease in body temperature, adjusted survival rates were likely to eliminate 14.6% during the 1-year follow-up. The DCA suggested the applicability of the model 3 in clinical practice and the RCS revealed a consistent higher mortality in hypothermia group.

CONCLUSIONS

Low body temperature was associated with increased mortality in critically ill patients with coronary heart disease.

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.

Temperature management in the intensive care unit: a practical survey from China

Introduction: Temperature management is an important aspect of the treatment of critically ill patients, but there are differences in the measurement and management of temperature in different Intensive Care Units (ICUs). The objective of this study was to understand the current situation of temperature measurement and management in ICUs in China, and to provide a basis for standardized temperature management in ICUs.Methods: A 20-question survey was used to gather information on temperature management strategies from ICUs across China. Data such as method and frequency of temperature measurement, management goals, cooling measures, and temperature management recommendations were collected.Results: A total of 425 questionnaires from unique ICUs were included in the study, with responses collected from all provinces and autonomous regions in China. Mercury thermometers were the most widely used measurement tool (82.39%) and the axilla was the most common measurement site (96.47%). There was considerable variability in the frequency of temperature measurement, the temperature at which intervention should begin, intervention duration, and temperature management goals. While there was no clearly preferred drug-based cooling method, the most widely used equipment-based cooling method was the ice blanket machine (93.18%). The most frequent recommendations for promoting temperature management were continuous monitoring and targeted management.Conclusion: Our investigation revealed a high level of variability in the methods of temperature measurement and management among ICUs in China. Since fever is a common clinical symptom in critically ill patients and can lead to prolonged ICU stays, we propose that standardized guidelines are urgently needed for the management of body temperature (BT) in these patients.

Accuracy of a Dual-Sensor Heat-Flux (DHF) Non-Invasive Core Temperature Sensor in Pediatric Patients Undergoing Surgery

Accurate temperature measurement is crucial for the perioperative management of pediatric patients, and non-invasive thermometry is necessary when invasive methods are infeasible. A prospective observational study was conducted on 57 patients undergoing elective surgery. Temperatures were measured using a dual-sensor heat-flux (DHF) thermometer (Tcore™) and a rectal temperature probe (TRec), and the agreement between the two measurements was assessed. The DHF measurements showed a bias of +0.413 °C compared with those of the TRec. The limits of agreement were broader than the pre-defined ±0.5 °C range (-0.741 °C and +1.567 °C). Although the DHF sensors tended to overestimate the core temperature compared to the rectal measurements, an error grid analysis demonstrated that 95.81% of the DHF measurements would not have led to a wrong clinical decision, e.g., warming or cooling when not necessary. In conclusion, the low number of measurements that would have led to incorrect decisions suggests that the DHF sensor can be considered an option for continuous temperature measurement when more invasive methods are infeasible.

Fever and Leukocytosis Are Poor Predictors of Bacterial Coinfection in Patients With COVID-19 and Influenza Who Are Receiving Extracorporeal Membrane Oxygenation

Background

Fever and leukocytosis are 2 parameters commonly cited in clinical practice as indications to perform an infectious workup in patients receiving extracorporeal membrane oxygenation (ECMO), but their utility is unknown.

Methods

All patients who received ECMO between December 2014 and December 2020 with influenza or COVID-19 were included in this retrospective cohort study. Cultures were included if they were drawn from patients without signs of decompensation. Maximum temperature and white blood cell count were recorded on the day of culture collection. Workups with infections were compared with those that were negative.

Results

Of the 137 infectious workups in this 45-patient cohort, 86 (63%) were performed in patients with no signs of decompensation, totaling 165 cultures. These workups yielded 10 (12%) true infections. There were no differences in median (IQR) temperature (100.4 °F [100.2-100.8] vs 100.4 °F [99.3-100.9], P = .90) or white blood cell count (18.6 cells/mL [16.8-20.1] vs 16.7 cells/mL [12.8-22.3], P = .90) between those with and without infections.

Conclusions

In patients with influenza or COVID-19 who require ECMO, fever and leukocytosis were common indications for infectious workups, yet results were frequently negative. Despite their use in clinical practice, fever and leukocytosis are not reliable indicators of infection in patients who are hemodynamically stable and receiving ECMO.

Temperature control after cardiac arrest

Managing temperature is an important part of post-cardiac arrest care. Fever or hyperthermia during the first few days after cardiac arrest is associated with worse outcomes in many studies. Clinical data have not determined any target temperature or duration of temperature management that clearly improves patient outcomes. Current guidelines and recent reviews recommend controlling temperature to prevent hyperthermia. Higher temperatures can lead to secondary brain injury by increasing seizures, brain edema and metabolic demand. Some data suggest that targeting temperature below normal could benefit select patients where this pathology is common. Clinical temperature management should address the physiology of heat balance. Core temperature reflects the heat content of the head and torso, and changes in core temperature result from changes in the balance of heat production and heat loss. Clinical management of patients after cardiac arrest should include measurement of core temperature at accurate sites and monitoring signs of heat production including shivering. Multiple methods can increase or decrease heat loss, including external and internal devices. Heat loss can trigger compensatory reflexes that increase stress and metabolic demand. Therefore, any active temperature management should include specific pharmacotherapy or other interventions to control thermogenesis, especially shivering. More research is required to determine whether individualized temperature management can improve outcomes.

Antimicrobial stewardship in the intensive care unit

High resistance rates to antimicrobials continue to be a global health threat. The incidence of multidrug-resistant (MDR) microorganisms in intensive care units (ICUs) is quite high compared to in the community and other units in the hospital because ICU patients are generally older, have higher numbers of co-morbidities and immune-suppressed; moreover, the typically high rates of invasive procedures performed in the ICU increase the risk of infection by MDR microorganisms. Antimicrobial stewardship (AMS) refers to the implementation of coordinated interventions to improve and track the appropriate use of antibiotics while offering the best possible antibiotic prescription (according to dose, duration, and route of administration). Broad-spectrum antibiotics are frequently preferred in ICUs because of greater infection severity and colonization and infection by MDR microorganisms. For this reason, a number of studies on AMS in ICUs have increased in recent years. Reducing the use of broad-spectrum antibiotics forms the basis of AMS. For this purpose, parameters such as establishing an AMS team, limiting the use of broad-spectrum antimicrobials, terminating treatments early, using early warning systems, pursuing infection control, and providing education and feedback are used. In this review, current AMS practices in ICUs are discussed.

Clinical impact of multidisciplinary carbapenem stewardship interventions: a retrospective cohort study

BACKGROUND

Antimicrobial stewardship (AMS) program aims to optimise antimicrobial utilisation and curb antimicrobial resistance. We investigated the clinical impact of AMS among patients with carbapenem in medical wards of a tertiary hospital.

METHODS

A retrospective cohort study was conducted on hospitalised adult patients treated with carbapenem and reviewed by a multidisciplinary AMS team. We compared the clinical outcomes of accepted (n = 103) and not-accepted AMS intervention cases (n = 37). The outcomes evaluated include trends of total white blood cells (TWBC), C-reactive protein (CRP), body temperature at day-7, and clinical status at day-30 post-AMS intervention.

RESULTS

The interventions included discontinuation (50%), de-escalation (47.9%) and escalation (2.1%) of antibiotics, where the acceptance rate was 67.1%, 80.6% and 66.7%, respectively. Overall, we found no significant difference in clinical outcomes between accepted and not-accepted AMS interventions at day-7 and day-30 post-interventions. On day-7, 62.0% of patients in the accepted group showed decreased or normalised TWBC and CRP levels compared to 47.4% of the not-accepted group (p = 0.271). The mortality at day-30 (32% versus 35%, p = 0.73), discharge rate (53.4% versus 45.9%, p = 0.437), and median length of hospital stay (36.0 versus 30.0 days, p = 0.526) between the groups were comparable. The predictors of 30-day mortality in the study subjects were Charlson Comorbidity Index > 3 (OR: 2.84, 95% CI 1.28-6.29, p = 0.010) and being febrile at day-7 (OR: 4.58, 95% CI 1.83-11.5, p = 0.001).

CONCLUSION

AMS interventions do not result in significant adverse clinical impact and mortality risk.

Escherichia coli-induced inflammatory responses are temperature-dependent in human whole blood ex vivo

Systemic inflammatory conditions are often associated with hypothermia or hyperthermia. Therapeutic hypothermia is used in post-cardiac arrest and some other acute diseases. There is a need for more knowledge concerning the effect of various temperatures on the acute inflammatory response. The complement system plays a crucial role in initiating the inflammatory response. We hypothesized that temperatures above and below the physiologic 37 °C affect complement activation and cytokine production ex vivo. Lepirudin-anticoagulated human whole blood from 10 healthy donors was incubated in the presence or absence of Escherichia coli at different temperatures (4 °C, 12 °C, 20 °C, 33 °C, 37 °C, 39 °C, and 41 °C). Complement activation was assessed by the terminal C5b-9 complement complex (TCC) and the alternative convertase C3bBbP using ELISA. Cytokines were measured using a 27-plex assay. Granulocyte and monocyte activation was evaluated by CD11b surface expression using flow cytometry. A consistent increase in complement activation was observed with rising temperature, reaching a maximum at 41 °C, both in the absence (C3bBbP p < 0.05) and presence (C3bBbP p < 0.05 and TCC p < 0.05) of E. coli. Temperature alone did not affect cytokine production, whereas incubation with E. coli significantly increased cytokine levels of IL-1β, IL-2, IL-6, IL-8, IFN-γ, and TNF at temperatures > 20 °C. Maximum increase occurred at 39 °C. However, a consistent decrease was observed at 41 °C, significant for IL-1β (p = 0.003). Granulocyte CD11b displayed the same temperature-dependent pattern as cytokines, with a corresponding increase in endothelial cell apoptosis and necrosis. Thus, blood temperature differentially determines the degree of complement activation and cytokine release.

Differentiating abdominal pain due to COVID-19 associated multisystem inflammatory syndrome from children with acute appendicitis: a score system

PURPOSE

Differentiating abdominal pain due to coronavirus disease (COVID-19)-associated multisystem inflammatory syndrome (MIS-C) in children with acute appendicitis (AA) can cause diagnostic dilemmas. This study aimed to evaluate the efficacy of a previously described scoring system and improve its diagnostic ability in differentiating between these diseases.

METHODS

This study was conducted between March 2020 and January 2022. Patients who had MIS-C with gastrointestinal system (GIS) involvement and patients who underwent surgery for appendicitis were included. First, all patients were evaluated using the new scoring system (NSS). The groups were compared by adding new MISC-specific parameters to NSS. The scoring system was evaluated using propensity score matching (PSM).

RESULTS

A total of 35 patients with abdominal pain due to GIS involvement in MIS-C (group A) and 37 patients with AA who had ALT, PRC, and D-dimer results at their first admission (group B) were included in the study. The mean age of patients in group A was lower than that of patients in group B (p < 0.001). False NSS positivity was found in 45.7% of the patients with MIS-C. Lymphocyte (p = 0.021) and platelet counts (p = 0.036) were significantly lower in the blood count and serum D-dimer (p = 0.034), C-reactive protein (CRP) (p < 0.001), and procalcitonin (p < 0.001) were significantly higher in the MIS-C group. We created a scoring system called the Appendicitis-MISC Score (AMS) using the NSS and new parameters. The sensitivity and specificity of AMS diagnostic scores were 91.9% and 80%, respectively.

CONCLUSION

MIS-C with GIS involvement may present as acute abdomen. It is difficult to differentiate this condition from acute appendicitis. AMS has been shown to be useful for this differentiation.

Infections in Critically Ill Children

Health care-associated infections (HAI) directly influence the survival of children in pediatric intensive care units (PICU), the most common being central line-associated bloodstream infection (CLABSI) 25-30%, followed by ventilator-associated pneumonia (VAP) 20-25%, and others such as catheter-associated urinary tract infection (CAUTI) 15%, surgical site infection (SSI) 11%. HAIs complicate the course of the disease, especially the critical one, thereby increasing the mortality, morbidity, length of hospital stay, and cost. The incidence of HAI in Western countries is 6.1-15.1% and in India, it is 10.5 to 19.5%. The advances in healthcare practices have reduced the incidence of HAIs in the recent years which is possible due to strict asepsis, hand hygiene practices, surveillance of infections, antibiotic stewardship, and adherence to bundled care. The burden of drug resistance and emerging infections are increasing with limited antibiotics in hand, is still a dreadful threat. The most common manifestation of HAIs is fever in PICU, hence the appropriate targeted search to identify the cause of fever should be done. Proper isolation practices, judicious handling of devices, regular microbiologic audit, local spectrum of organisms, identification of barriers in compliance of hand hygiene practices, appropriate education and training, all put together in an efficient and sustained system improves patient outcome.

Association between first 24-h mean body temperature and mortality in patients with diastolic heart failure in intensive care unit: A retrospective cohort study

Background

Body temperature (BT) has been used to evaluate the outcomes of patients with various diseases. In this study, patients with diastolic heart failure (DHF) in the intensive care unit (ICU) were examined for a correlation between BT and mortality.

Methods

This was a retrospective cohort study of the Medical Information Mart for Intensive Care (MIMIC)-IV dataset. A total of 4,153 patients with DHF were included. The primary outcomes were 28-day ICU and higher in-hospital mortality rates. BT was used in the analyses both as a continuous variable and as a categorical variable. According to the distribution of BT, the patients were categorized into three groups (hypothermia BT <36.5°C, normal 36.5°C ≤ BT <37.5°C, and hyperthermia BT ≥37.5°C). Multivariate logistic regression analysis was performed to explore the association between BT and patient outcomes.

Results

The proportions of the groups were 23.6, 69.2, and 7.2%, respectively. As a continuous variable, every 1°C increase in BT was associated with a 21% decrease in 28-day ICU mortality (OR: 0.79, 95% CI: 0.66-0.96, and p = 0.019) and a 23% decrease in in-hospital mortality (OR: 0.77, 95% CI: 0.66-0.91; and p = 0.002). When BT was used as a categorical variable, hypothermia was significantly associated with both 28-day ICU mortality (OR: 1.3, 95% CI: 1.03-1.65; and p = 0.026) and in-hospital mortality (OR: 1.31, 95% CI: 1.07-1.59; and p = 0.008). No statistical differences were observed between 28-day ICU mortality and in-hospital mortality with hyperthermia after adjustment.

Conclusion

The first 24-h mean BT after ICU admission was associated with 28-day ICU and in-hospital mortality in patients with DHF. Hypothermia significantly increased mortality, whereas hyperthermia did not.

Understanding healthcare provider preferences for ordering respiratory cultures to diagnose ventilator associated pneumonia: A discrete choice experiment

OBJECTIVE

Ventilator-associated pneumonia (VAP) can be overdiagnosed on the basis of positive respiratory cultures in the absence of clinical findings of pneumonia. We determined the perceived diagnostic importance of 6 clinical attributes in ordering a respiratory culture to identify opportunities for diagnostic stewardship.

DESIGN

A discrete choice experiment presented participants with a vignette consisting of the same "stem" plus variations in 6 clinical attributes associated with VAP: chest imaging, oxygenation, sputum, temperature, white blood cell count, and blood pressure. Each attribute had 3-4 levels, resulting in 32 total scenarios. Participants indicated whether they would order a respiratory culture, and if yes, whether they preferred the bronchoalveolar lavage or endotracheal aspirate sample-collection method. We calculated diagnostic utility of attribute levels and relative importance of each attribute.

SETTING AND PARTICIPANTS

The survey was administered electronically to critical-care clinicians via a Qualtrics survey at a tertiary-care academic center in the United States.

RESULTS

In total, 59 respondents completed the survey. New radiograph opacity (utility, 1.15; 95% confidence interval [CI], 0.99-1.3), hypotension (utility, 0.88; 95% CI, 0.74-1.03), fever (utility, 0.76; 95% CI, 0.62-0.91) and copious sputum (utility, 0.75; 95% CI, 0.60-0.90) had the greatest perceived diagnostic value that favored ordering a respiratory culture. Radiograph changes (23%) and temperature (20%) had the highest relative importance. New opacity (utility, 0.35; 95% CI, 0.17-0.52) and persistent opacity on radiograph (utility, 0.32; 95% CI, 0.05-0.59) had the greatest value favoring bronchoalveolar lavage over endotracheal aspirate.

CONCLUSION

Perceived high diagnostic value of fever and hypotension suggest that sepsis vigilance may drive respiratory culturing and play a role in VAP overdiagnosis.

Computational modeling of targeted temperature management in post-cardiac arrest patients

Our core body temperature is held around [Formula: see text]C by an effective internal thermoregulatory system. However, various clinical scenarios have a more favorable outcome under external temperature regulation. Therapeutic hypothermia, for example, was found beneficial for the outcome of resuscitated cardiac arrest patients due to its protection against cerebral ischemia. Nonetheless, practice shows that outcomes of targeted temperature management vary considerably in dependence on individual tissue damage levels and differences in therapeutic strategies and protocols. Here, we address these differences in detail by means of computational modeling. We develop a multi-segment and multi-node thermoregulatory model that takes into account details related to specific post-cardiac arrest-related conditions, such as thermal imbalances due to sedation and anesthesia, increased metabolic rates induced by inflammatory processes, and various external cooling techniques. In our simulations, we track the evolution of the body temperature in patients subjected to post-resuscitation care, with particular emphasis on temperature regulation via an esophageal heat transfer device, on the examination of the alternative gastric cooling with ice slurry, and on how anesthesia and the level of inflammatory response influence thermal behavior. Our research provides a better understanding of the heat transfer processes and therapies used in post-cardiac arrest patients.

CRRT influences PICCO measurements in febrile critically ill patients

The aim of this study was to investigate whether continuous renal replacement therapy (CRRT) influences the global end-diastolic volume index (GEDVI), cardiac index (CI), and extravascular lung water index (EVLWI) measured by Pulse Index Continuous Cardiac Output (PICCO) in febrile patients. Fifteen fever patients were included in this study. CI, GEDVI, EVLWI, heart rate (HR), and mean arterial pressure (MAP) were measured at five time-points: before CRRT (T0), immediately after CRRT started (T1), 15 min after CRRT started (T2), immediately after CRRT stopped (T3), and 15 min after CRRT stopped (T4). Results have shown that CI and GEDVI were decreased significantly in T1 (CI: 4.09 ± 0.72 vs 2.81 ± 0.58 L/min m², P = 0.000 and GEDVI: 727.86 ± 63.47 vs 531.07 ± 66.63 mL/m², P = 0.000). However, CI and GEDVI were significantly increased in T3 (CI: 4.09 ± 0.72 vs 7.23 ± 1.32 L/min m², P = 0.000 and GEDVI 727.86 ± 63.47 vs 1339.17 ± 121.52 mL/m², P = 0.000). There were no significant differences in T2 and T4. Among the five-time points, no measurement errors were observed with regards to HR, MAP, and EVLWI. Therefore, the data herein contained suggests that PICCO measurements should begin 15 min after the start or stop of CRRT.

Infrared thermography as a modality for tracking cutaneous temperature change and post-mortem interval in the critical care setting

PURPOSE

To evaluate the potential use of cutaneous facial temperature change as measured by an infrared camera as a marker of postmortem interval (PMI) in the minutes immediately following death.

METHODS

This was a prospective, observational pilot study using a convenience sample of all deaths which occurred in a room in an Intensive Care Unit equipped with a ceiling mounted thermal camera. Cutaneous temperature measurements were taken from 60 min antemortem to as long as possible postmortem.

RESULTS

A total of 134 separate measurements was taken from 5 patients, with 65 occurring antemortem, and 69 occurring post-mortem. The longest recorded post-mortem time was 130 min. A Kruskal-Wallis ANOVA testing the hypothesis that there was a difference in facial temperature at each of the different timepoints showed significance (p = 0.029). Post-Hoc comparisons were then performed to compare median temperature values at each timeframe to the baseline value. Compared to baseline, there was a significant difference in facial temperature at 30, 60, and 90 min (p = 0.007, p = 0.01, p = 0.016) (Table 2).

CONCLUSION

There is a statistically significant cutaneous facial temperature change in patients immediately following death as measured by a thermal camera. There is potential for infrared thermography to identify changes immediately before and after death in environments where traditional temperature measurement cannot be accomplished. More work needs to be done to confirm whether a precise postmortem interval (PMI) could be derived from these values.

Comparison of cutaneous facial temperature using infrared thermography to standard temperature measurement in the critical care setting

To assess the accuracy and precision of infrared cameras compared to traditional measures of temperature measurement in a temperature, humidity, and distance controlled intensive care unit (ICU) population. This was a prospective, observational methods comparison study in a single centre ICU in Metropolitan Melbourne, Australia. A convenience sample of 39 patients admitted to a single room equipped with two ceiling mounted thermal imaging cameras was assessed, comparing measured cutaneous facial temperature via thermal camera to clinical temperature standards. Uncorrected correlation of camera measurement to clinical standard in all cases was poor, with the maximum reported correlation 0.24 (Wide-angle Lens to Bladder temperature). Using the wide-angle lens, mean differences were − 11.1 °C (LoA  − 14.68 to  − 7.51),  − 11.1 °C ( − 14.3 to  − 7.9), and  − 11.2 °C ( − 15.23 to  − 7.19) for axillary, bladder, and oral comparisons respectively (Fig. 1a). With respect to the narrow-angle lens compared to the axillary, bladder and oral temperatures, mean differences were  − 7.6 °C ( − 11.2 to  − 4.0),  − 7.5 °C ( − 12.1 to  − 2.9), and  − 7.9 °C ( − 11.6 to  − 4.2) respectively. AUCs for the wide-angle lens and narrow-angle lens ranged from 0.53 to 0.70 and 0.59 to 0.79 respectively, with axillary temperature demonstrating the greatest values. Infrared thermography is a poor predictor of patient temperature as measured by existing clinical standards. It has a moderate ability to discriminate fever. It is unclear if this would be sensitive enough for infection screening purposes.Fig. 1

Serum procalcitonin as a biomarker of bloodstream infection & focal bacterial infection in febrile patients

Background & objectives:

Bacteraemia is a serious form of infection in patients presenting with fever, thus, there is a necessity for a biomarker for rapid diagnosis of bacteraemia in such patients to make better therapeutic decisions. This study was conducted to measure the serum procalcitonin (PCT) levels at the time of initial presentation as a biomarker for identifying bacteraemia and as a predictor of mortality in patients admitted with acute fever.

Methods:

Four hundred and eighty patients, who presented with acute fever requiring admission to a tertiary care teaching hospital in south India, were prospectively studied. All patients were evaluated with a detailed history, physical examination, laboratory and imaging studies. Baseline serum PCT was measured for each patient within six hours of admission.

Results:

Among patients with single infectious cause (n=275), significantly higher median serum PCT levels were evident in bacteraemia compared to leptospirosis (P=0.002), dengue (P<0.001), scrub typhus (P<0.001) and evident focus of infection without bacteraemia (P=0.036). By receiver-operator characteristic curve analysis, at a cut-off value of >3.2 ng/ml, the sensitivity and specificity of serum PCT levels in predicting bacteraemia were 81.1 and 63.3 per cent, respectively. As per the worst-case scenario analysis, 91 (18.9%) patients had a poor outcome and these had significantly higher median serum PCT levels compared to survivors (n=389) [9.46 (2.03-44.4) vs. 1.23 (0.34-7.645); P<0.001]. At a cut-off value of >3.74 ng/ml, serum PCT levels at initial presentation predicted in-hospital mortality with a sensitivity and specificity of 67 and 67.5 per cent, respectively.

Interpretation & conclusions:

Our observations suggest that serum PCT level may be a useful biomarker for identifying bacteraemia as well as predicting mortality in patients with acute fever requiring admission to hospital.

Bundles of care for prevention of ventilator-associated pneumonia caused by carbapenem-resistant Klebsiella pneumoniae in the ICU

OBJECTIVE

To investigate the treatment efficacy of bundles of care for the prevention of ventilator-associated pneumonia (VAP) caused by carbapenem-resistant Klebsiella pneumoniae in the intensive care unit (ICU).

METHODS

A total of 102 patients undergoing mechanical ventilation in the ICU of our hospital were randomly assigned into a research group (n=51, bundles of care) and a control group (n=51, routine care). The incidence of VAP, pathogenic bacteria in the sputum, outcome and medication compliance (Morisky medication adherence scale (MMAS) score) of patients as well as the hand hygiene rate of nurses were compared between the two groups.

RESULTS

The research group showed significantly shorter time of mechanical ventilation and ICU stay, lower incidence of VAP and less ICU hospitalization costs than the control group (all P<0.05). The detection rate of pathogenic bacteria in the research group was significantly lower than that in the control group (P<0.01). Both the MMAS score and the hand hygiene rate of nurses were higher in the research group than in the control group (both P<0.01). The mortality of the research group was significantly lower than that of the control group (P<0.05).

CONCLUSION

Bundles of care for patients undergoing mechanical ventilation in ICU can greatly shorten the time of mechanical ventilation, reduce nosocomial infection, decrease the incidence of VAP and the mortality, and is conducive to improving the hand hygiene of nurses and the medication compliance of patients.

Effects of Hyperthermia on Intracranial Pressure and Cerebral Autoregulation in Patients with an Acute Brain Injury

Hyperthermia is a common detrimental condition in patients with an acute brain injury (ABI), which can worsen their prognosis and outcome. The aim of this study was to evaluate the effects of hyperthermia on intracranial pressure (ICP) and cerebral autoregulation (CA).Eight patients with ABI were studied. CA was assessed on the basis of the pressure reactivity index (PRx) coefficient. The ICP, cerebral perfusion pressure (CPP), and PRx were compared before and during development of hyperthermia. Hyperthermia was defined as an increase in cerebral temperature above 38.3 °C.Thirty-three episodes of hyperthermia were analyzed: 25 of these occurred on a background of initially normal ICP whereas 8 occurred on a background of initially elevated ICP, and 17 of the 33 episodes occurred on a background of initially intact autoregulation whereas 16 occurred on a background of initially impaired autoregulation.During hyperthermia, elevated ICP was found in 52% of instances where it was initially normal, and further progression of intracranial hypertension occurred in 100% of instances where ICP was initially elevated. The median ICP during hyperthermia was 24 [range quartiles 22-28] mmHg in instances where it was initially normal and 31 [quartiles 27-32] mmHg in instances where it was initially elevated (p < 0.01). The correlation coefficient between the brain temperature and ICP was 0.11 (p < 0.01). During hyperthermia, the number of episodes of ICP >20 mmHg increased by 41% in instances with intact autoregulation but ICP was above 20 mmHg and by 38% (p > 0.05) in instances with impaired autoregulation and ICP was 20 mmHg. The cerebral hyperthermia-associated increase in ICP was not associated with impaired autoregulation.

The Effect of Early Sedation With Dexmedetomidine on Body Temperature in Critically Ill Patients

OBJECTIVES

Previous case series reported an association between dexmedetomidine use and hyperthermia. Temperature data have not been systematically reported in previous randomized controlled trials evaluating dexmedetomidine. A causal link between dexmedetomidine administration and elevated temperature has not been demonstrated.

DESIGN

Post hoc analysis.

SETTING

Four ICUs in Australia and New Zealand.

PATIENTS

About 703 mechanically ventilated ICU patients.

INTERVENTIONS

Early sedation with dexmedetomidine versus usual care.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was mean daily body temperature. Secondary outcomes included the proportions of patients with body temperatures greater than or equal to 38.3°C and greater than or equal to 39°C, respectively. Outcomes were recorded for 5 days postrandomization in the ICU. The mean daily temperature was not different between the dexmedetomidine (n = 351) and usual care (n = 352) groups (36.84°C ± sd vs 36.78°C ± sd; p = 0.16). Over the first 5 ICU days, more dexmedetomidine group (vs usual care) patients had a temperature greater than or equal to 38.3°C (43.3% vs 32.7%, p = 0.004; absolute difference 10.6 percentage points) and greater than or equal to 39.0°C (19.4% vs 12.5%, p = 0.013; absolute difference 6.9 percentage points). Results were similar after adjusting for diagnosis, admitting temperature, age, weight, study site, sepsis occurrence, and the time from dexmedetomidine initiation to first hyperthermia recorded. There was a significant dose response relationship with temperature increasing by 0.30°C ±0.08 for every additional 1 μg/kg/hr of dexmedetomidine received p < 0.0002.

CONCLUSIONS

Our study suggests potentially important elevations in body temperature are associated with early dexmedetomidine sedation, in adults who are mechanically ventilated in the ICU.

Host Diagnostic Biomarkers of Infection in the ICU: Where Are We and Where Are We Going?

Purpose of Review

Early identification of infection in the critically ill patient and initiation of appropriate treatment is key to reducing morbidity and mortality. On the other hand, the indiscriminate use of antimicrobials leads to harms, many of which may be exaggerated in the critically ill population. The current method of diagnosing infection in the intensive care unit relies heavily on clinical gestalt; however, this approach is plagued by biases. Therefore, a reliable, independent biomarker holds promise in the accurate determination of infection. We discuss currently used host biomarkers used in the intensive care unit and review new and emerging approaches to biomarker discovery.

Recent Findings

White cell count (including total white cell count, left shift, and the neutrophil-leucocyte ratio), C-reactive protein, and procalcitonin are the most common host diagnostic biomarkers for sepsis used in current clinical practice. However, their utility in the initial diagnosis of infection, and their role in the subsequent decision to commence treatment, remains limited. Novel approaches to biomarker discovery that are currently being investigated include combination biomarkers, host 'sepsis signatures' based on differential gene expression, site-specific biomarkers, biomechanical assays, and incorporation of new and pre-existing host biomarkers into machine learning algorithms.

Summary

To date, no single reliable independent biomarker of infection exists. Whilst new approaches to biomarker discovery hold promise, their clinical utility may be limited if previous mistakes that have afflicted sepsis biomarker research continue to be repeated.

[Influence of cerebral hyperthermia on intracranial pressure and autoregulation of cerebral circulation in patients with acute brain injury]

Background. Hyperthermia is a common symptom in ICU patients with brain injury.

OBJECTIVE

To study the effect of hyperthermia on intracranial pressure (ICP) and cerebral autoregulation (Prx).

MATERIAL AND METHODS

There were 8 patients with acute brain injury, signs of brain edema and intracranial hypertension. Cerebral autoregulation was assessed by using of PRx. ICP, CPP, BP, PRx were measured before and during hyperthermia. We have analyzed 33 episodes of cerebral hyperthermia over 38.30 C. Statistica 10.0 (StatSoft) was used for statistical analysis.

RESULTS

Only ICP was significantly increased by 6 [3; 11] mm Hg (p<0.01). In patients with initially normal ICP, hyperthermia resulted increase of ICP in 48% of cases (median 24 [22; 28] mm Hg). In patients with baseline intracranial hypertension, progression of hypertension was noted in 100% cases (median 31 [27; 32] mm Hg) (p<0.01). Hyperthermia resulted intracranial hypertension regardless brain autoregulation status.

CONCLUSION

Cerebral hyperthermia in patients with initially normal ICP results intracranial hypertension in 48% of cases. In case of elevated ICP, further progression of intracranial hypertension occurs in 100% of cases. Cerebral hyperthermia is followed by ICP elevation in both intact and impaired cerebral autoregulation.

Changes in gastrointestinal cell integrity after marathon running and exercise-associated collapse

PURPOSE

Endurance exercise and hyperthermia are associated with compromised intestinal permeability and endotoxaemia. The presence of intestinal fatty acid-binding protein (I-FABP) in the systemic circulation suggests intestinal wall damage, but this marker has not previously been used to investigate intestinal integrity after marathon running.

METHODS

Twenty-four runners were recruited as controls prior to completing a standard marathon and had sequential I-FABP measurements before and on completion of the marathon, then at four and 24 h later. Eight runners incapacitated with exercise-associated collapse (EAC) with hyperthermia had I-FABP measured at the time of collapse and 1 hour later.

RESULTS

I-FABP was increased immediately on completing the marathon (T0; 2593 ± 1373 ng·l^-1) compared with baseline (1129 ± 493 ng·l^-1; p < 0.01) in the controls, but there was no significant difference between baseline and the levels at four hours (1419 ± 1124 ng·l^-1; p = 0.7), or at 24 h (1086 ± 302 ng·l^-1; p = 0.5). At T0, EAC cases had a significantly higher I-FABP concentration (15,389 ± 8547 ng.l^-1) compared with controls at T0 (p < 0.01), and remained higher at 1 hour after collapse (13,951 ± 10,476 ng.l^-1) than the pre-race control baseline (p < 0.05).

CONCLUSION

I-FABP is a recently described biomarker whose presence in the circulation is associated with intestinal wall damage. I-FABP levels increase after marathon running and increase further if the endurance exercise is associated with EAC and hyperthermia. After EAC, I-FABP remains high in the circulation for an extended period, suggesting ongoing intestinal wall stress.

Late Presentation of Linezolid-Induced Serotonin Syndrome After Maprotiline and Mirtazapine Therapy: A Case Report

OBJECTIVE

This report describes a 45-year-old man who developed serotonin syndrome on day 13 of linezolid therapy. This is unusual as it typically appears within 24 hours of linezolid initiation.

METHODS

The patient did not receive any serotonergic agents concurrently with linezolid; maprotiline and mirtazapine were stopped 17 days before the development of serotonin syndrome. On day 13 of linezolid administration, the patient exhibited diaphoresis, fever, confusion, agitation, disorientation, anxiety, and restlessness. His blood pressure was elevated with persistent tachycardia. He was then diagnosed with serotonin syndrome using the Hunter criteria.

RESULTS

Linezolid was discontinued and supportive measures were initiated, which resulted in the complete resolution of the syndrome.

CONCLUSIONS

This case report highlights that linezolid-induced serotonin syndrome can occur late in the course of therapy and the importance of the serotonergic agent washout period before the introduction of linezolid. A multidisciplinary team is important for optimal diagnosis and management of such cases.

Uncontrolled central hyperthermia by standard dose of bromocriptine: A case report

BACKGROUND

Some patients present to the intensive care unit due to noninfectious pathologies resulting in fever, especially acute neurological injuries, including brain trauma and intracranial haemorrhage. The cause has been identified to be central hyperthermia characterized by a high core temperature and a poor response to antipyretics and antibiotics. However, no proper guidelines on how to treat central hyperthermia have been developed for clinical practice.

CASE SUMMARY

A 63-year-old woman was transferred to our hospital due to injury after a traffic accident. Eight hours after admission, her pupils enlarged bilaterally from 2.5 mm to 4.0 mm. She developed severe coma and underwent decompressive craniectomy. She was diagnosed with central hyperthermia after surgery and was prescribed bromocriptine. The standard dose of bromocriptine could not control her hyperpyrexia, and we prescribed 30 mg a day to control her temperature.

CONCLUSION

Bromocriptine may be effective in controlling central hyperthermia and have a dosage effect.

Thermoregulation: A journey from physiology to computational models and the intensive care unit

Thermoregulation plays a vital role in homeostasis. Many species of animals as well as humans have evolved various physiological mechanisms for body temperature control, which are characteristically flexible and enable a fine-tuned spatial and temporal regulation of body temperature in different environmental conditions and circumstances. Human beings normally maintain a core body temperature at around 37°C, and maintenance of this relatively high temperature is critical for survival. Therefore, principles of thermoregulatory control have also important clinical implications. Infections can cause the body temperature to rise internally and several diseases can cause a dysfunction of thermoregulatory mechanisms. Moreover, the utilization of thermotherapies in treating various diseases has been known for thousands of years with a recent resurgence of interest. An increasing amount of research suggests that targeted temperature management is of paramount importance to patient outcomes in certain clinical scenarios. We provide a concise summary of the basic concepts of thermoregulation. Emphasis is given to the principles of thermoregulation in humans in basic pathological states and to targeted temperature management strategies in the clinical environment, with special attention on therapeutic hypothermia in postcardiac arrest patients. Finally, the discussion is focused on the potential offered by computational thermophysiological models for predicting thermal responses of patients in various clinical circumstances, for proposing new perspectives in the design of novel thermal therapies, and to optimize targeted temperature management strategies. This article is categorized under: Cardiovascular Diseases > Cardiovascular Diseases>Computational Models Cardiovascular Diseases > Cardiovascular Diseases>Environmental Factors Cardiovascular Diseases > Cardiovascular Diseases>Biomedical Engineering.

Noninfectious causes of fever in adults

Fever is a common clinical sign encountered in hospitalized patients and often represents the cardinal sign of infectious processes. However, a number of noninfectious etiologies causing fever should be considered prior to initiating broad-spectrum antibiotic therapy. Reducing unnecessary antibiotic use is crucial in an era of increasing resistance.

When not to start antibiotics: avoiding antibiotic overuse in the intensive care unit

BACKGROUND

Most intensive care unit (ICU) patients receive broad-spectrum antibiotics. While lifesaving in some, in others these treatments may be unnecessary and place patients at risk of antibiotic-associated harms.

OBJECTIVES

To review the literature exploring how we diagnose infection in patients in the ICU and address the safety and utility of a 'watchful waiting' approach to antibiotic initiation with selected patients in the ICU.

SOURCES

A semi-structured search of PubMed and Cochrane Library databases for articles published in English during the past 15 years was conducted.

CONTENT

Distinguishing infection from non-infectious mimics in ICU patients is uniquely challenging. At present, we do not have access to a rapid point-of-care test that reliably differentiates between individuals who need antibiotics and those who do not. A small number of studies have attempted to compare early aggressive versus conservative antimicrobial strategies in the ICU. However, this body of literature is small and not robust enough to guide practice.

IMPLICATIONS

This issue will not likely be resolved until there are diagnostic tests that rapidly and reliably identify the presence or absence of infection in the ICU population. In the meantime, prospective trials that identify clinical situations wherein it is safe to delay or withhold antibiotic initiation in the ICU until the presence of an infection is proven are warranted.

[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).

Targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke: consensus recommendations

BACKGROUND

A modified Delphi approach was used to identify a consensus on practical recommendations for the use of non-pharmacological targeted temperature management in patients with intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke with non-infectious fever (assumed neurogenic fever).

METHODS

Nine experts in the management of neurogenic fever participated in the process, involving the completion of online questionnaires, face-to-face discussions, and summary reviews, to consolidate a consensus on targeted temperature management.

RESULTS

The panel's recommendations are based on a balance of existing evidence and practical considerations. With this in mind, they highlight the importance of managing neurogenic fever using a single protocol for targeted temperature management. Targeted temperature management should be initiated if the patient temperature increases above 37.5°C, once an appropriate workup for infection has been undertaken. This helps prevent prophylactic targeted temperature management use and ensures infection is addressed appropriately. When neurogenic fever is detected, targeted temperature management should be initiated rapidly if antipyretic agents fail to control the temperature within 1 h, and should then be maintained for as long as there is potential for secondary brain damage. The recommended target temperature for targeted temperature management is 36.5-37.5°C. The use of advanced targeted temperature management methods that enable continuous, or near continuous, temperature measurement and precise temperature control is recommended.

CONCLUSIONS

Given the limited heterogeneous evidence currently available on targeted temperature management use in patients with neurogenic fever and intracerebral haemorrhage, subarachnoid haemorrhage, or acute ischaemic stroke, a Delphi approach was appropriate to gather an expert consensus. To aid in the development of future investigations, the panel provides recommendations for data gathering.

Targeted temperature management in neurological intensive care unit

Targeted temperature management (TTM) shows the most promising neuroprotective therapy against hypoxic/ischemic encephalopathy (HIE). In addition, TTM is also useful for treatment of elevated intracranial pressure (ICP). HIE and elevated ICP are common catastrophic conditions in patients admitted in Neurologic intensive care unit (ICU). The most common cause of HIE is cardiac arrest. Randomized control trials demonstrate clinical benefits of TTM in patients with post-cardiac arrest. Although clinical benefit of ICP control by TTM in some specific critical condition, for an example in traumatic brain injury, is still controversial, efficacy of ICP control by TTM is confirmed by both in vivo and in vitro studies. Several methods of TTM have been reported in the literature. TTM can apply to various clinical conditions associated with hypoxic/ischemic brain injury and elevated ICP in Neurologic ICU.