Accuracy of temporal artery thermometry in neonatal intensive care infants

Temporal Artery Thermometry in Pediatric Patients: Systematic Review and Meta-Analysis

PROBLEM

Non-invasive thermometry methods have been used as substitutes for intra-corporeal ones in order to decrease patient discomfort and risk for complications, yet the evaluation of their performance is necessary. Our aim was to synthesize the evidence on the accuracy and precision of temporal artery (TA) thermometry, as well as on its sensitivity and specificity for fever detection.

ELIGIBILITY CRITERIA

This systematic review and meta-analysis included method-comparison studies, which compared TA temperature measurements with invasive thermometry ones, were published between 2000 and 2018, and were conducted on patients aged <18 years.

SAMPLE

Thirty articles were selected for inclusion in the final analysis after screening those identified by searches in CINAHL, PubMed, Web of Science, Cochrane Library, EMBASE and Scopus.

RESULTS

Quantitative synthesis indicated that pooled mean TA temperature was lower than core temperature by 0.01 °C (95% limits of agreement, -0.06 °C to 0.03 °C). Average summary sensitivity and specificity for fever detection were 0.72 (95% confidence interval, 0.66-0.79) and 0.91 (95% confidence interval, 0.86-0.93) respectively. Subgroup analysis indicated a trend toward larger temperature underestimation in febrile patients and in ages ≤4 years.

CONCLUSIONS

Despite its satisfactory accuracy, precision and specificity, TA thermometry has low sensitivity when used in pediatric patients, which does not allow satisfactory fever detection.

IMPLICATIONS

TA thermometry cannot be recommended for replacing rectal temperature measurement methods in children, due to its high proportion of false negative readings during screening for fever.

Evaluation of Noninvasive Thermometers in an Endoscopy Setting

The measurement of body temperature is an important aspect of assessment prior to invasive procedures. The purpose of the study was to determine the level of agreement between temporal artery, noncontact infrared, and disposable oral electronic thermometers to a clinical reference device (nondisposable oral electronic thermometer) in outpatients prior to an endoscopic procedure. A descriptive, method-comparison study design was used to compare 3 noninvasive thermometers with a clinical reference device. Four noninvasive temperatures were measured with 3 test devices (temporal artery with ear tap; temporal artery without ear tap; disposable oral electronic; and noncontact infrared), followed by measurement with the clinical reference device (nondisposable, oral electronic). Differences (bias) and limits of agreement (±1.96 SD) were calculated for the test devices and graphed using Bland-Altman method. Clinically acceptable levels of agreement were set at a bias of 0.54 °F or less and precision of 0.90 °F or less. A total of 25 endoscopy patients (N = 14 female; N = 11 male) were studied, with temperatures ranging from 97.5 to 98.9, averaging 98.1 ± 0.3 °F. All thermometers, with the exception of the noncontact infrared (0.66 °F), had acceptable ranges for use in clinical practices. Findings from this study support the use of both temporal artery and disposable oral electronic thermometers in afebrile outpatients but not the noncontact infrared thermometer.

Comparison of Axillary and Temporal Artery Thermometry in Preterm Neonates

OBJECTIVE

To compare the accuracy of infrared temporal artery thermometry with axillary thermometry in a cohort of preterm neonates between 28 and 36 weeks postmenstrual age.

DESIGN

Descriptive repeated measures design with randomization to temperature measurement order.

SETTING

Level III NICU in the Central/Southeastern United States.

PARTICIPANTS

Sixty-eight neonates born between 28 weeks and 36 weeks postmenstrual age cared for in incubators or open cribs.

METHODS

Neonates were randomly assigned to temperature measurement order (axillary followed by temporal artery or temporal artery followed by axillary). Temperature pairs were taken once during the day shift and once during the night shift. Behavioral states were assessed before, during, and after temperature measurement.

RESULTS

Neonates were predominantly female (64.7%) with a mean age of 6.6 days and a mean gestational age of 32.7 weeks, and most were cared for in incubators (n = 55). Noninferiority was observed between the two temperature methods (Holm-Bonferroni criterion = .025, p < .001). There was no statistically significant difference in the behavioral states of the neonates between the two temperature methods. It took nurses significantly longer to use the axillary thermometer than to use the temporal artery thermometer (p < .001).

CONCLUSION

Temporal artery temperature measurements were as accurate as axillary temperature measurements in low-birth-weight neonates in the NICU. Nurses spent less time measuring with the temporal artery method than with the axillary method.

Elevated body temperature in ischemic stroke associated with neurological improvement

OBJECTIVES

Some studies suggest that high body temperature within the first few hours of ischemic stroke onset is associated with improved outcome. We hypothesized an association between high body temperature on admission and detectable improvement within 6-9 hours of stroke onset.

MATERIALS AND METHODS

Consecutive ischemic stroke patients with NIHSS scores obtained within 3 hours and in the interval 6-9 hours after stroke onset were included. Body temperature was measured on admission.

RESULTS

A total of 315 patients with ischemic stroke were included. Median NIHSS score on admission was 6. Linear regression showed that NIHSS score 6-9 hours after stroke onset was inversely associated with body temperature on admission after adjusting for confounders including NIHSS score <3 hours after stroke onset (P<.001). The same result was found in patients with proximal middle cerebral occlusion on admission.

CONCLUSIONS

We found an inverse association between admission body temperature and neurological improvement within few hours after admission. This finding may be limited to patients with documented proximal middle cerebral artery occlusion on admission and suggests a beneficial effect of higher body temperature on clot lysis within the first three hours.

Temporal Artery Temperature Measurement in the Neonate

Objective We compared an infrared temporal artery thermometer with our clinical standard axillary thermometer for temperature measurements in neonatal patients. Study Design We measured temporal artery (T_ta), axillary (T_ax, clinical standard), and rectal (T_r, gold standard) temperatures of 49 infants. The difference between T_r and T_ta was compared with that between T_r and T_ax, and the data were analyzed based on bed type and postmenstrual age. Results The mean T_ta, T_ax, and T_r were 37.16 (SD 0.36) °C, 36.61 (SD 0.30) °C, and 36.82 (SD 0.30) °C, respectively. The measurements by these methods were all significantly different. The mean T_r-T_ax was 0.21 (SD 0.26) °C, and the mean T_r-T_ta was -0.34 (SD 0.37) °C, indicating that T_ax was closer to T_r than was T_ta (p < 0.0001). T_ta agreed more closely with T_r for infants in cribs than for those in incubators. Adjusting for bed type and body weight, with each week of postmenstrual age, the discrepancy between T_r-T_ta and T_r-T_ax decreased by 0.005°C (p = 0.034). Conclusion Compared with the gold standard, T_r, T_ta is not more accurate than T_ax. The temporal artery thermometer was less accurate for infants in incubators than for infants in cribs. The accuracy of temporal artery temperature increased with postmenstrual age.

Comparison of Temporal Artery Thermometry with Axillary and Rectal Thermometry in Full Term Neonates

OBJECTIVE

To assess the efficacy of temporal artery thermometer in febrile and hypothermic neonates in comparison to axillary thermometer.

METHODS

It was a cross sectional observational study. Study participants included 210 neonates admitted in neonatal intensive care unit of a tertiary care teaching hospital, divided into three groups of 70 each, namely normothermic, febrile and hypothermic. Temperatures were measured using temporal artery, axillary and rectal thermometers in each patient.

RESULTS

Mean rectal temperature was found to be comparable to mean temporal artery temperature in normothermic babies. Temporal artery thermometer had a better sensitivity to diagnose fever, than hypothermia. Also, temporal artery temperature showed a good correlation with rectal temperature in normothermic and febrile group and not in hypothermic neonates.

CONCLUSIONS

Temporal artery thermometer can accurately detect temperature in febrile and normothermic fullterm neonates but not in hypothermic neonates. Further studies are required before advocating temporal artery thermometry as a replacement of rectal thermometry among this group of population.

Cost minimisation analysis of thermometry in two different hospital systems

INTRODUCTION

Temperature monitoring can be accomplished by various methods, including oral (OT), rectal (RT), axillary (AT), tympanic membrane (TMT) and temporal artery (TAT) thermometry, with varying amounts of cost incurred by healthcare systems.

METHODS

The potential thermometry cost savings in two hospital systems-University Hospital Centre Zagreb (UHCZ), which uses TMT (device Covidien Genius 2) and University of Michigan Hospitals (UMH), which relies on OT, RT and AT (device Welch Allyn suretemp plus 692)-were analysed to evaluate institution-wide TAT (device Exergen TAT-5000) implementation. Two scenarios were developed: scenario 1, comparing costs for a period of 1, 3 and 5 years; scenario 2, calculation of the number of measurements per device for TAT to be cost-effective.

RESULTS

At UHCZ, use of TAT would bring budget savings regardless of the number of devices per bed and the number of years observed. Savings would range from US$0.08 million (one device per bed, impact for 1 year) to US$1.8 million (one device per 10 beds, impact for 5 years). At UMH, use of TAT would lead to budget savings if one device per 10 beds were acquired, but only over a period of 3 or 5 years. Other TAT scenarios were associated with budget costs at UMH even after a period of 5 years.

CONCLUSIONS

Sensitivity analyses showed that the price of current consumables had the highest impact on the model in both hospital settings, with TAT up to 10 times cheaper in that regard over TMT at UHCZ, potentially leading to considerable budget savings within a year of hospital-wide implementation.

A practical comparison of temporal artery thermometry and axillary thermometry in neonates under different environments

AIM

Thermoregulatory stability and monitoring are crucial in neonatal care. However, the current standard of temperature measurement using Axillary Thermometry (AT) poses multiple limitations. Temporal Artery Thermometry (TT) is a promising new method, which thus begs the question: Can TT replace AT in neonates? Previous studies reveal conflicting results, with none involving a Southeast-Asian multi-ethnic neonatal population under different environments.

METHODS

A 6-month prospective comparative study involving neonates managed in a tertiary neonatal centre. Subjects were divided into 4 groups based on the required nursing environment: A) Room air B) Phototherapy C) Radiant warmers D) Incubators. Six hundred and sixty-one paired TT and AT temperature readings were obtained, with concurrent FLACC scoring to evaluate the discomfort associated with each thermometry method.

RESULTS

TT readings were higher than AT in all groups. The mean temperature difference between both methods (TT-AT) was lowest in Group A (0.10 ± 0.19°C), followed by Groups B (0.50 ± 0.33°C), C (0.97 ± 0.76°C) and D (1.15 ± 0.57°C) respectively. Bland-Altman analysis revealed good clinical agreement (± 0.5°C) between both methods in Group A (7-0.27,0.47). However, Groups B (-0.14,1.13), C (-0.51,2.45) and D (0.03,2.27) showed poor agreement. Multiple GEE analysis revealed Malay ethnicity to be an additional predictor of decreased TT-AT ( β = -0.13, p = 0.012). Compared to TT, AT was associated with higher discomfort levels (p <0.001).

CONCLUSIONS

Given the good agreement and increased comfort with TT use, our study confirms that TT is comparable to AT for neonates nursed in room air. TT is therefore recommended for the temperature screening and monitoring of neonates nursed on ambient air. Its use in other environments and factors predictive of comparability of both methods requires further study.

Temperature measurements with a temporal scanner: systematic review and meta-analysis

OBJECTIVES

Systematic review and meta-analysis on the diagnostic accuracy of temporal artery thermometers (TAT).

DESIGN

Systematic review and meta-analysis. The index test consisted of temperature measurement with TAT. The reference test consisted of an estimation of core temperature.

PARTICIPANTS

Clinical patients as well as healthy participants, with or without fever.

INTERVENTIONS

Literature search in PubMed, Embase, Cinahl and Web of Science. Three reviewers selected articles for full-text reading after which a further selection was made. Risk of bias was assessed with QUADAS-2. Pooled difference and limits of agreement (LoA) were estimated with an inverse variance weighted approach. Subgroup and sensitivity analyses were performed. Sensitivity and specificity were estimated using hierarchical models. Quality of evidence was assessed according to the GRADE system.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was measurement accuracy expressed as mean difference ± 95% LoA. A secondary outcome was sensitivity and specificity to detect fever. If tympanic thermometers were assessed in the same population as TAT, these results were recorded as well.

RESULTS

37 articles comprising 5026 participants were selected. Pooled difference was -0.19 °C (95% LoA -1.16 to 0.77 °C), with moderate quality of evidence. Pooled sensitivity was 0.72 (95% CI 0.61 to 0.81) with a specificity of 0.94 (95% CI 0.87 to 0.97). The subgroup analysis revealed a trend towards underestimation of the temperature for febrile patients. There was a large heterogeneity among included studies with wide LoA which reduced the quality of evidence.

CONCLUSIONS

TAT is not sufficiently accurate to replace one of the reference methods such as rectal, bladder or more invasive temperature measurement methods. The results are, however, similar to those with tympanic thermometers, both in our meta-analysis and when compared with others. Thus, it seems that TAT could replace tympanic thermometers with the caveat that both methods are inaccurate.

TRIAL REGISTRATION NUMBER

CRD42014008832.

Accuracy of peripheral thermometers for estimating temperature: a systematic review and meta-analysis

BACKGROUND

Body temperature is commonly used to screen patients for infectious diseases, establish diagnoses, monitor therapy, and guide management decisions.

PURPOSE

To determine the accuracy of peripheral thermometers for estimating core body temperature in adults and children.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL Plus from inception to July 2015.

STUDY SELECTION

Prospective studies comparing the accuracy of peripheral (tympanic membrane, temporal artery, axillary, or oral) thermometers with central (pulmonary artery catheter, urinary bladder, esophageal, or rectal) thermometers.

DATA EXTRACTION

2 reviewers extracted data on study characteristics, methods, and outcomes and assessed the quality of individual studies.

DATA SYNTHESIS

75 studies (8682 patients) were included. Most studies were at high or unclear risk of patient selection bias (74%) or index test bias (67%). Compared with central thermometers, peripheral thermometers had pooled 95% limits of agreement (random-effects meta-analysis) outside the predefined clinically acceptable range (± 0.5 °C), especially among patients with fever (-1.44 °C to 1.46 °C for adults; -1.49 °C to 0.43 °C for children) and hypothermia (-2.07 °C to 1.90 °C for adults; no data for children). For detection of fever (bivariate random-effects meta-analysis), sensitivity was low (64% [95% CI, 55% to 72%]; I2 = 95.7%; P < 0.001) but specificity was high (96% [CI, 93% to 97%]; I2 = 96.3%; P < 0.001). Only 1 study reported sensitivity and specificity for the detection of hypothermia.

LIMITATIONS

High-quality data for some temperature measurement techniques are limited. Pooled data are associated with interstudy heterogeneity that is not fully explained by stratified and metaregression analyses.

CONCLUSION

Peripheral thermometers do not have clinically acceptable accuracy and should not be used when accurate measurement of body temperature will influence clinical decisions.

PRIMARY FUNDING SOURCE

None.

Temporal artery thermometry in children younger than 5 years: a comparison with rectal thermometry

BACKGROUND

Temporal artery (TA) thermometry has come as one of the new methods for temperature measurement, especially in children in whom accurate temperature monitoring can save lives. The device which is convenient and simple to use is yet to gain popularity in several parts of the world, as there are conflicting reports of its accuracy. This study compares the accuracy of the TA thermometry in children younger than 5 years using the rectal thermometry as the gold standard.

METHODS

Temperature was measured simultaneously in eligible children younger than 5 years from the forehead and rectum using the TA thermometer (TAT-2000C Exergen, USA) and standard mercury in glass rectal thermometer, respectively. The difference between the mean temperatures obtained by the 2 thermometry methods was tested using the paired t test. Pearson correlation coefficient, linear regression, and Bland-Altman plot were also used to test the relationship and agreement between the 2 instruments. The sensitivity, specificity, and positive and negative predictive values were also calculated.

RESULTS

Overall, the mean TA temperature (37.80°C ± 1.07°C) was significantly lower than the mean rectal temperature (38.07°C ± 0.95°C), P < 0.001. In neonates, however, the mean difference was not significant, 0.02 ± 0.59 (P = 0.810). There was a significant positive correlation between the rectal and the temporal temperatures (r = 0.80, P < 0.01). The Bland-Altman plot showed wide variation in the limit of agreement between the rectal and the TA temperatures which ranged from -1.02°C to +1.56°C. The sensitivity of the TA thermometer was 64.6% and 83.5%, respectively, at a TA fever cutoff of 38.0°C and 37.7°C.

CONCLUSIONS

Temporal artery thermometer is not accurate enough for the measurement of core body temperature in children younger than 5 years. However, it may be used as a tool for screening for fever in very busy clinics and emergency room at a fever cutoff of 37.7°C.

Axillary and rectal thermometry in the newborn: do they agree?

Background

Accurate measurement of body temperature is critical for the assessment of a newborn’s general well-being. In nursery settings, the gold standard rectal thermometry has been replaced by the axillary method. However, evidence pertaining to the agreement between axillary and rectal thermometry in the newborn is controversial. In this cross-sectional study, the agreement between axillary and rectal temperature in newborns, as well as the effects of neonatal, maternal and environmental factors on this agreement were investigated.

Methods

The mean difference between axillary and rectal temperatures was compared in stable term and preterm newborns using paired t-test for the means of differences, Pearson correlation coefficient (r), and the Bland-Altman plot. Stepwise multivariate regression assessed predictors of this difference in the overall group and by gestational age categories.

Results

The study included 118 newborns with gestational ages ranging from 29 to 41 weeks, median birth weight of 2980 grams (IQR: 2321.3-3363.8). Axillary and rectal temperatures correlated significantly (r = 0.5, p = 0.000) and had similar overall means but differed in 34–36 weeks gestation newborns (p = 0.01). Correlation between both methods increased with advancing gestational age being highest in term newborns (r = 0.6, p = 0.000). Bland-Altman plots revealed good agreement in gestational ages above 29 weeks. The difference between measurements increased with Cesarean delivery (ß = 0.2; 95% CI: 0.02, 0.38), but decreased with advancing chronological age (ß = -0.01; 95% CI: -0.02,-0.01), and with gestational age (ß = -0.05; 95% CI: -0.08,-0.01).

Conclusion

In clinically stable term and preterm infants, axillary thermometry is as reliable as rectal measurement. Predictors of agreement between the two methods include gestational age, chronological age and mode of delivery. Further studies are needed to confirm this agreement in sick newborns and in extremely premature infants.

[Systematic review and meta-analyses of diagnostic accuracy of infrared thermometer when identifying fever in children]

PURPOSE

Infrared thermometers are increasingly used as a convenient, non-invasive assessment method for febrile children. However, the diagnostic accuracy of the infrared thermometer for children has been questioned, particularly in relation to sensitivity and specificity. The aim of this study was to evaluate diagnostic accuracy of infrared thermometers in febrile children.

METHODS

Articles published between 1966 and 2012 from periodicals indexed in the Ovid Medline, Embase, CINAHL, Cochrane, KoreaMed, NDSL, KERIS and other databases were selected, using the following keywords: 'infrared thermometer'. The QUADAS-II was applied to assess the internal validity of the diagnostic studies. Selected studies were analyzed using meta-analysis with MetaDisc 1.4.

RESULTS

Nineteen diagnostic studies with high methodological quality, involving 4,304 children, were included. The results of meta-analysis showed that the pooled sensitivity, specificity and AUC (Area Under the Curve) of infrared tympanic thermometers in children over 1 year were 0.80 (95% CI 0.78, 0.81), 0.94 (95% CI 0.93, 0.95) and 0.95 respectively. However the diagnostic accuracy of infrared tympanic thermometers in children with hyperthermia was low.

CONCLUSION

The diagnostic accuracy of infrared tympanic thermometer was similar to axillary and rectal thermometers indicating a need for further research to substantiate these findings in children with hyperthermia.

Body temperature and major neurological improvement in tPA-treated stroke patients

BACKGROUND

Major neurological improvement (MNI) at 24 hours represents a marker of early recanalization in ischaemic stroke. Although low body temperature is considered neuroprotective in cerebral ischaemia, some studies have suggested that higher body temperature may promote clot lysis in the acute phase of ischaemic stroke. We hypothesized that higher body temperature was associated with MNI in severe stroke patients treated with tPA, suggesting a beneficial effect of higher body temperature on clot lysis and recanalization.

METHODS

Patients with ischaemic stroke or transient ischaemic attack (TIA) treated with tPA between February 2006 and August 2012 were prospectively included and retrospectively analysed. Body temperature was measured upon admission. MNI was defined by a ≥8 point improvement in NIHSS score at 24 hours as compared to NIHSS score on admission. No significant improvement (no-MNI) was defined by either an increase in NIHSS score or a decrease of ≤2 points at 24 hours in patients with an admission NIHSS score of ≥8.

RESULTS

Of the 2351 patients admitted with ischaemic stroke or TIA, 347 patients (14.8%) were treated with tPA. A total of 32 patients (9.2%) had MNI and 56 patients (16.1%) had no-MNI. Patients with MNI had higher body temperatures compared with patients with no-MNI (36.7°C vs 36.3°C, P = 0.004). Higher body temperature was independently associated with MNI when adjusted for confounders (OR 5.16, P = 0.003).

CONCLUSION

Higher body temperature was independently associated with MNI in severe ischaemic stroke patients treated with tPA. This may suggest a beneficial effect of higher body temperature on clot lysis and recanalization.

Is higher body temperature beneficial in ischemic stroke patients with normal admission CT angiography of the cerebral arteries?

Background

Low body temperature is considered beneficial in ischemic stroke due to neuroprotective mechanisms, yet some studies suggest that higher temperatures may improve clot lysis and outcomes in stroke patients treated with tissue plasminogen activator (tPA). The effect of increased body temperature in stroke patients treated with tPA and with normal computed tomography angiography (CTA) on admission is unknown. We hypothesized a beneficial effect of higher body temperature in the absence of visible clots on CTA, possibly due to enhanced lysis of small, peripheral clots.

Methods

Patients with ischemic stroke admitted to our Stroke Unit between February 2006 and April 2013 were prospectively registered in a database (Bergen NORSTROKE Registry). Ischemic stroke patients treated with tPA with normal CTA of the cerebral arteries were included. Outcomes were assessed by the modified Rankin Scale (mRS) after 1 week. An excellent outcome was defined as mRS=0, and a favorable outcome as mRS=0–1.

Results

A total of 172 patients were included, of which 48 (27.9%) had an admission body temperature ≥37.0°C, and 124 (72.1%) had a body temperature <37.0°C. Body temperature ≥37.0°C was independently associated with excellent outcomes (odds ratio [OR]: 2.8; 95% confidence interval [CI]: 1.24–6.46; P=0.014) and favorable outcomes (OR: 2.8; 95% CI: 1.13–4.98; P=0.015) when adjusted for confounders.

Conclusion

We found an association between higher admission body temperature and improved outcome in tPA-treated stroke patients with normal admission CTA of the cerebral arteries. This may suggest a beneficial effect of higher body temperature on clot lysis in the absence of visible clots on CTA.

Temperature measurement in the preterm and term neonate: a review of the literature

The maintenance of a constant body temperature is important to all humans but even more so for newborn babies (neonates), especially those born pre-term. Because accurate measurement of body temperature is an important component of thermoregulation management in the neonate, a review of the literature was undertaken to determine the most appropriate method and site of temperature measurement in both the preterm and term neonate. The available evidence indicates that the axilla remains the most common place for temperature measurement.

Persistent middle cerebral artery occlusion associated with lower body temperature on admission

BACKGROUND

Low body temperature is considered neuroprotective in ischemic stroke, yet some studies suggest that low body temperature may also inhibit clot lysis and recanalization. We hypothesized that low body temperature was associated with persistent proximal middle cerebral artery (MCA) occlusion in patients with acute ischemic stroke presenting with symptoms of proximal MCA occlusion, suggesting a possible detrimental effect of low body temperature on recanalization.

METHODS

All patients with acute ischemic stroke admitted to our Stroke Unit between February 2006 and August 2012 were prospectively registered in a database. Computed tomography (CT) angiography was performed in patients admitted <6 hours after stroke onset. Based on presenting symptoms, patients were classified according to the Oxford Community Stroke Project classification (OCSP). Patients with symptomatic proximal MCA occlusion were compared to patients with total anterior circulation infarct (TACI) without MCA occlusion on CT angiography.

RESULTS

During the study period, 384 patients with acute ischemic stroke were examined with CT angiography. A total of 79 patients had proximal MCA occlusion and 31 patients had TACI without MCA occlusion. Median admission body temperatures were lower in patients with MCA occlusion compared to patients without occlusion (36.3°C versus 36.7°C, P = 0.027). Admission body temperature <36.5°C was independently associated with persistent MCA occlusion when adjusted for confounders in multivariate analyses (odds ratio 3.7, P = 0.007).

CONCLUSION

Our study showed that low body temperature on admission was associated with persistent proximal MCA occlusion. These results may support a possible detrimental effect of low body temperature on clot lysis and recanalization.

Accuracy of infrared thermometers in very low birth weight infants and impact on newborn behavioural states

AIM

To study the impact on newborn behavioural states and accuracy of three infrared thermometers compared with digital axillary thermometer measurements in very low birth weight infants.

METHODS

Single-centre prospective observational study. Preterm infants born <1500-g birth weight were eligible. Infants were observed for pre-measurement behaviour state using a five-point neonatal behaviour observation tool. One infrared temperature was taken from each of the devices, followed by an axillary measurement. Further behaviour-state observations were recorded following infrared and axillary measurements.

RESULTS

One hundred measurements were collected from each infrared device among a cohort of 42 very low birth weight infants. Only one infrared device showed satisfactory agreement with bias -0.071 (95% limits of agreement -0.68 to 0.54). The other two devices demonstrated poor agreement: bias -1.34; 95% limits of agreement -2.62 to -0.5 and bias -0.56; 95% limits of agreement -1.38 to 0.25. Neonatal behavioural scores showed only minimal changes when infrared measurements were performed but increased significantly following axillary measurements. The difference between the two modalities was statistically significant with a mean increase of 1.44 points following axillary measurements (95% confidence interval 1.21 to 1.67, P < 0.001).

CONCLUSIONS

Temperature measurements taken with infrared thermometers demonstrated less disruption to preterm infants' behavioural state, however accuracy of devices varied.

Low body temperature associated with severe ischemic stroke within 6 hours of onset: The Bergen NORSTROKE Study

Background

Hypothermia is considered neuroprotective and a potential treatment in cerebral ischemia. Some studies suggest that hyperthermia may promote clot lysis. We hypothesized that low body temperature would prolong time to spontaneous clot lysis resulting in an association between low body temperature and severe neurological deficits in the early phase of ischemic stroke.

Methods

In this prospective study, patients (n = 516) exhibiting ischemic stroke with symptom onset within 6 hours were included. Body temperature and National Institute of Health Stroke Scale (NIHSS) score were registered on admission. Because low body temperature on admission may be secondary to immobilization due to large stroke, separate analyses were performed on patients with cerebral hemorrhage admitted within 6 hours (n = 85).

Results

Linear regression showed that low body temperature on admission was independently associated with a high NIHSS score within 6 hours of stroke onset in patients with ischemic stroke (P < 0.001). The association persisted when NIHSS was measured at 24 hours after admission. No such associations were found in patients with cerebral hemorrhage admitted within 6 hours of stroke onset.

Conclusion

Our study suggests that low body temperature within 6 hours of symptom onset is associated with severe ischemic stroke. This is in support of our hypothesis, although other contributing mechanisms cannot be excluded.