Circadian rhythmicity and homeostatic stability in thermoregulation

Do ginger footbaths improve symptoms of insomnia more than footbaths with warm water only? - A randomized controlled study

OBJECTIVES

To compare the effects between warm water (WW) and ginger footbaths (WW+ginger) on sleep quality and warmth regulation in adults with self-reported insomnia symptoms.

METHODS

A prospective randomized-controlled study in which 28 participants (mean age 50.9 years, 64.3% women, insomnia symptom duration 11.4 years) were randomized to receive WW (n = 13) or WW+ginger (n = 15) daily for 2 weeks. Treatment involved nightly footbaths (12 liters of 38-42 °C warm tap water, maximum duration 20 min) with and without topical ginger (80 g of powdered ginger rhizomes).

MAIN OUTCOME MEASURES

The primary outcome measure was self-reported sleep quality (global score from Pittsburgh Sleep Quality Index, PSQI) at 2 weeks. Secondary outcomes included measures of insomnia severity (Insomnia Severity Index, ISI) and warmth regulation (Herdecke Warmth Perception Questionnaire, HWPQ and 24-hour distal-proximal skin temperature gradient, DPG).

RESULTS

WW+ginger had no greater effect on PSQI (mean between-difference 0.0 [95% CI -3.0 to 2.9], Cohen's d=0.0) or ISI (-0.2 [-3.9 to 3.4], 0.0) than WW. Nor were there any significant differences in HWPQ perceived warmth (0.1 ≥d≥0.5) or DPG (0.1 ≥d≥0.4) between WW and WW+ginger. Both groups improved over time in PSQI (WW+ginger: d=0.7, WW: d=1.3) and ISI (WW+ginger: d=0.8, WW: d=1.0). Perceived warmth of the feet increased only in WW+ginger over time (d=0.6, WW: d=0.0).

CONCLUSIONS

This dose of ginger (6.67 g/liter) did not have greater effects on sleep quality, insomnia severity or warmth regulation than WW. Considering effect sizes, costs and risks, the use of WW would be recommended over WW+ginger in this patient population.

Acupuncture for the Treatment of Paraneoplastic Night Sweats

This case report describes acupuncture treatment to manage paraneoplastic night sweating secondary to pancreatic cancer. A 56-year-old gentleman with a 2-month history of night sweating responded well over a 10-week course of acupuncture treatment. Acupuncture was selected for symptom management after no success was achieved with pharmacological and conventional managements. The severity of night sweating had reduced from 9/10 to 1/10 on visual analog scale at the end of treatment. This case report suggests that acupuncture has a favorable effect on paraneoplastic night sweating in patients with advanced pancreatic cancer and recommends further research.

Accuracy of Noninvasive Core Temperature Measurement in Acutely Ill Adults: The State of the Science

Accurate temperature measurement is critical to the assessment and management of temperature fluctuation in the acutely ill adult. Unfortunately, an accurate, noninvasive method to measure core temperature has yet to be established, and current instruments produce a wide range of temperatures for any given patient. This article provides an integrative review of studies comparing selected invasive and noninvasive temperature measurement methods in acutely ill, hospitalized adult patients. Medline and CINAHL databases were searched to locate published studies on temperature measurement in the adult hospitalized patient. A partial list of primary search terms included core temperature measurement, oral temperature measurement, temporal artery thermometry, and tympanic thermometers. Studies that were data based and included comparison of a tympanic, temporal artery, and/or oral noninvasive temperature measurement to a pulmonary artery or esophageal invasive core measurement in an adult population were included in the analysis. The search method produced 223 publications and abstracts for initial review; 23 (10%) met the inclusion criteria. The only study evaluating the use of temporal artery thermometry in the adult population found the instrument to be unreliable. Results also indicate that high-quality evidence supporting the accuracy of tympanic thermometry, the preferred instrument for noninvasive core temperature measurement in many acute care settings, is lacking, and in fact, the most recent high-quality studies evaluating the accuracy of this instrument fail to show support for its use. Evidence does, however, support the use of oral thermometry as an accurate means of temperature assessment in the adult, acutely ill population.

The clinical utility of Memorial Symptom Assessment-Short Form and Condensed Memorial Symptom Assessment Scale in Turkish lung cancer patients

INTRODUCTION

Symptom assessment is essential in the palliative care of patients with cancer. We studied the Memorial Assessment Scale Test-Short Form (MSAS-SF) and Condensed Memorial Assessment Test (CMSAS) in Turkish lung cancer patients.

MATERIAL AND METHOD

Fifty-one patients with lung cancer (47 non-small, 4 small cell) were staged according to the International Association for the Study of Lung Cancer 2007 and filled the MSAS-SF. Karnofsky performance status, TNM staging, MSAS-SF and CMSAS scores were recorded. The study was approved by the local research ethics committee.

RESULTS

The mean age of 51 patients was 61.7 ± 9. Fifty-one percent were staged as M1 while 49% were staged as M0. The mean values for global distress index, PHYS (physical symptom distress), PSYCH (psychological symptom score) and MSAS-SUM were 1.15 ± 0.8, 0.9 ± 0.8, 1.13 ± 1.03 and 0.82 ± 0.47 in order. The mean values for CPHYS (physical symptom distress for Condensed MSAS), CPSYCH (psychological symptom score for CMSAS) and CSUM (sum scores) were 1.2 ± 0.75, 1.22 ± 1.1 and 1.16 ± 0.69 in order. Cronbach's alpha coefficients for MSAS-SF and CMSAS were 0.861 and 0.728 in order. Summary scores for both MSAS-SF and CMSAS-SF were significantly higher in patients with M1 disease than from M0 disease. In addition, PHYS and MSAS-SUM in MSAS-SF were significantly correlated with T and N stage. The area under curve for MSAS-SF and CMSAS were 0.793 and 0.70 in order.

CONCLUSION

MSAS-SF and CMSAS demonstrated significantly higher scores in lung cancer patients with M1 disease than patients with M0 disease. Further studies are needed to evaluate the usefulness of MSAS-SF and CMSAS in lung cancer patients.

Body temperature circadian rhythm variability corresponds to left ventricular systolic dysfunction in decompensated cardiomyopathic hamsters

BACKGROUND

A declining amplitude of body temperature circadian rhythm (BTCR) predicts decompensation or death in cardiomyopathic hamsters. We tested the hypothesis that changes in BTCR amplitude accompany significant changes in left ventricular (LV) size and function.

METHODS AND RESULTS

Using intraperitoneal transmitters, we continuously monitored the temperature of 30 male BIO TO-2 Syrian dilated cardiomyopathic hamsters. Cosinor analysis was used to detect significant changes--defined as changes >1 standard deviation from the baseline amplitude for 3 consecutive days--in BTCR amplitude over each hamster's lifespan. The Student t-test was used to compare BTCR variability and LV size and function (as assessed by 2D echocardiography) between baseline and the time that BTCR amplitude declined. All hamsters received 10 mg/kg furosemide daily. At the time of BTCR amplitude decline, functional parameters had changed significantly (P < .0001) from baseline: ejection fraction (0.31 ± 0.09% vs. 0.52 ± 0.08%), LV end-systolic volume (0.11 ± 0.03 vs. 0.05 ± 0.02 cm(3)), and LV end-diastolic volume (0.16 ± 0.04 vs. 0.10 ± 0.03 cm(3)).

CONCLUSIONS

In decompensated cardiomyopathic hamsters, a decline in BTCR amplitude was associated with progression of heart failure and cardiac decompensation. Variation in BTCR warrants further investigation because of its potential implications for the diagnosis and treatment of cardiovascular disorders.

Non-invasive continuous cerebral temperature monitoring in patients treated with mild therapeutic hypothermia: an observational pilot study

AIM OF THE STUDY

To investigate if body temperature as measured with a prototype of a non-invasive continuous cerebral temperature sensor using the zero-heat-flow method to reflect the oesophageal temperature (core temperature) during mild therapeutic hypothermia after cardiac arrest.

METHODS

In patients over 18 years old with restoration of spontaneous circulation after cardiac arrest, a temperature sensor that uses the zero-heat-flow principle was placed on the forehead during the periods of cooling and re-warming. This temperature was compared to oesophageal temperature as the primary temperature-monitoring site. To assess agreement, we used the Bland-Altman approach and Lin's concordance correlation coefficient.

RESULTS

From September 2008 to April 2009, data from 19 patients were analysed. The median time from restoration of spontaneous circulation until temperature sensor application was 53min (interquartile range, 31; 96). All sensors were removed when a core temperature of 36 degrees C was reached. These measurements were in agreement with oesophageal temperature measurements. No allergic reaction, rash or other irritation occurred on the skin around or under the probes. Bland-Altman results showed a bias of -0.12 degrees C and 95% limits of agreement of -0.59 and +0.36 degrees C. Lin's concordance correlation coefficient was 0.98.

CONCLUSIONS

Body temperature measurements using a non-invasive continuous cerebral temperature sensor prototype that uses the zero-heat-flow method accurately reflected oesophageal temperature measurements during mild therapeutic hypothermia in patients with restoration of spontaneous circulation after cardiac arrest.

The impact of altered climatic conditions and altitude on circadian physiology

Knowing the output of the "body clock" is fundamental to the science of chronobiology. As the clock resides within the suprachiasmatic nuclei, direct measurement is not feasible and therefore, characteristics of the clock are often inferred from the measurement of marker rhythms, one of which is core temperature. Core temperature is often the marker rhythm of choice due to ease of measurement, particularly in field conditions. However, if the output of the "body clock" is to be inferred from measurement of this variable, it is important to establish whether environmental conditions change or moderate the circadian rhythm of core temperature. Although the majority of circadian patterns do demonstrate independence from such exogenous influences, there does appear to be seasonal variation to their period. Given that humans can easily travel to environments of altered temperature and altitude, there is a need to ascertain the exact effect of such change on the rhythm of core temperature. This review will therefore outline the evidence that the circadian rhythm of core temperature is affected by ambient temperature and by hypoxia. Furthermore, the review will discuss whether these environmental factors act as zeitgebers (affecting the endogenous rhythm) or as masking influences of the inherent rhythm.

Are Infrared and Thermistor Thermometers Interchangeable for Measuring Localized Skin Temperature?

Localized skin temperature must be measured by accurate and reliable thermometers to effectively evaluate treatment outcomes, monitor changes, and predict potential complications. This study compared localized skin temperature measurements with a contact thermistor thermometer used as a reference standard and a noncontact infrared (IR) skin thermometer to determine their interchangeability with calculated Bland-Altman limits of agreement. Fifty-five adults ages 50 to 89 participated in the study in which data were collected in a climate-controlled room over 3 measurement periods, 1 week apart. The thermistor and IR thermometers were interchangeable with a limit of agreement of ± 1.5°C. This limit of agreement is acceptable as a reference standard for IR thermometers to measure localized skin temperature in clinical settings.

Measuring circadian temperature rhythm

Experimental control and mathematical techniques increase confidence that results of circadian temperature rhythm studies reflect true changes in the circadian timing system versus coupling with exogenous synchronizers. Masking effects represent confounding influences in studies that are concerned with the endogenous temperature rhythm. Because it is technically difficult to measure directly the behavior of the endogenous timing system, marker rhythms are used as proxy measures. However in addition to entraining, the external environment exerts a direct masking effect on the monitored rhythm. Methods for measuring circadian temperature rhythm are reviewed in this article. Constant routine, forced desynchrony, and purification methods represent attempts, at an experimental or mathematical level, to remove masking effects and more accurately capture the endogenous circadian temperature rhythm. Exogenous factors have not been subjected to the same scrutiny as the endogenous features of circadian temperature rhythm. But it is the environmental context, the extent to which the endogenous features are adaptively modified by the field environment, that will ultimately determine the biological value of circadian temperature rhythm to the organism. Thus, nurse investigators are encouraged to use rigorous methods to study both endogenous circadian temperature rhythm and exogenous rhythms.