Detection of factors influencing circadian rhythms on Intensive Care inpatients and hospitalization: Protocol for an observational study.

AIMS: Identify the prevalence of circadian health disorders in ICU and hospitalized patients. Stablish the relationship of the circadian system with light, temperature, noise and nursing activities. BACKGROUND: Commonly, self-assessment through subjective questionnaires is used for research about sleep quality. However, more reliable and valid measures should be applied objectively to find out the real prevalence of the problem. There is a negative relationship between circadian rhythms and hospitalization. In this study, we will analyse sleep patterns and hospital environments to implement measures to improve the quality of care related to sleep. DESIGN: Descriptive observational study. It is estimated that 975 patients from 13 hospitals need to be recruited from ICU and hospitalization units. The sample should meet the following criteria: Patients over 18 admitted to ICU and medical units, length of stay between 96-148 hr, with no visual, hearing or moderate-severe cognitive impairment. Variables: Sleep variables are collected with an electronic device (named Kronowise® and Kronobed®), circadian and infrared light exposure, environmental noise, temperature, unit structural characteristics, nursing care (from 0 to 6 a.m.) and, characteristics of hospitalization period. The study, registered on Clinical Trials, initiated in December 2019 and it will continue up to December 2022. DISCUSSION: Using objective and subjective measures of sleep and circadian rhythms, this study will shed light on the factors that negatively affect the hospitalized patients' sleep quality and circadian health. The ultimate goal is to design hospital guidelines to minimize the adverse effects on the dependent variables studied. Arguably, these guidelines will contribute to reducing the risk of these alterations and it will also serve to improve the nursing activities. CONCLUSION: We expect to obtain adequate results for the creation of a protocol to improve the circadian health, quality of care and health outcomes related to sleep in patients.

Effect of unilateral superior cervical ganglionectomy on mandibular bone in rats.

OBJECTIVE: To assess the effect of local sympathectomy on mandibular bone during tooth eruption in rats. METHODS: The effect of a unilateral superior cervical ganglionectomy (Gx) on morphometry of ipsi- and contralateral mandible and volumetric bone density (as assessed by peripheral computed tomography) was examined 30 days after surgery. RESULTS: Only a few mandibular morphometric parameters decreased significantly after denervation in rats subjected to a unilateral Gx and a contralateral sham-operation. Mandibular volumetric bone density decreased significantly after sympathetic denervation. In a second experiment, carried out under conditions of unilateral unimpeded eruption of incisors performed ipsilaterally or contralaterally to a unilateral Gx, a significant interaction "denervation x type of eruption" was found for most morphometric parameters. Further analysis indicated higher morphometric indexes in denervated mandibles than in the innervated ones under impeded incisor eruption conditions, and lower morphometric indexes in denervated mandibles than in the innervated ones under unimpeded incisor eruption conditions. Unimpeded eruption augmented total volumetric bone density providing the innervation was intact and caused opposite effects on cortical volumetric bone density in the presence of innervation (increase) or absence of innervation (decrease). Trabecular volumetric bone density decreased significantly after sympathetic denervation. CONCLUSION: The results support a role of the sympathetic nervous system in the regulation of bone remodeling.