Are circadian rhythms in disarray in patients with chronic critical illness?

Aim: The aim of our study is to assess circadian rhythms in patients with chronic critical illness due to severe brain injury in intensive care unit by establishing the relation between melatonin and cortisol secretion, considering astronomical time and the sleep-wake cycle in chronic critical illness. Materials and methods: The study included 54 adult patients with chronic critical illness who resided in the intensive care unit for at least 30 days. The level of consciousness was determined using the CRS-R scale. We did the continuous electroencephalographic (EEG) monitoring with polygraphic leads for 24 h. Also, we determined the serum levels of cortisol and melatonin using the tandem mass spectrometry method with ultra-performance liquid chromatography. Results: 90.74 % of patients had one acrophase in melatonin secretion curve, which suggests the preservation of the rhythmic secretion of melatonin. These acrophases of the melatonin rhythm occurred during the night time in 91.8 % of patients. Most of the patients (69.3 %) slept during the period from 2:00 to 4:00 a.m. The evening levels of cortisol and melatonin had an inverse relation (rs=0.61, p<0.05), i.e., a decrease in the level of cortisol secretion accompanies an increase in melatonin. Conclusions: We concluded from our study that the rhythmic secretion of melatonin and cortisol is preserved in patients with chronic critical illness that resulted from severe brain injury. No statistically significant discrepancy between melatonin and cortisol secretion, day-and-night time and the sleep-wake cycle are found. We may focus our future work on finding more reliable methods to stabilize the preservation of circadian rhythms to protect vital organ functions.

Two-year outcomes of patients with prolonged disorders of consciousness: a prospective cohort study in Russian Federation.

BACKGROUND: Epidemiological data on prolonged disorders of consciousness (pDOC) are not available due to lack of research in this field. The objective of this pioneering prospective cohort study in the Russian Federation was to collect the data on the survival and the level of consciousness of patients with pDOC, as well as to search for prognostic markers of survival and improvement of the level of consciousness on long-terms outcomes (up to 24 months). METHODS: All patients (n=184) had pDOC and were admitted to the Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology. We assessed the neurological status and acquired follow-up diagnosis as well. Out of total patients: anoxic brain injury (ABI) (n=52), vascular lesions (VL) (n=50), traumatic brain injury (TBI) (n=74), and other causes (n=8). Changes in patients' vital and conscious status were recorded in four-time slices: 3, 6, 12, and 24 months after the event that led to pDOC. RESULTS: The survival rate is less than 30%, and the rate of recovery in terms of consiousness is 21%, which are both low, though do not differ significantly from existing data for this category of patients. Unprofessional home care may have a role to play in the declined long-term survival rate. We still do not have reliable prognostic markers among demographical and clinical indices; however, younger age can be considered the only significant predictor of survival and positive dynamics in the level of consciousness. CONCLUSIONS: We expect that our research will help to personalize and help the patient and families with the appropriate clinical as well as social measures.

One-Year Demographical and Clinical Indices of Patients with Chronic Disorders of Consciousness.

This work aims to evaluate the prognostic value of the demographical and clinical data on long-term outcomes (up to 12 months) in patients with severe acquired brain injury with vegetative state/unresponsive wakefulness syndrome (VS/UWS/UWS) or a minimally conscious state (MCS). Patients (n = 211) with VS/UWS/UWS (n = 123) and MCS (n = 88) were admitted to the Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology after anoxic brain injury (n = 53), vascular lesions (n = 59), traumatic brain injury (n = 93), and other causes (n = 6). At the beginning of the 12-month study, younger age and a higher score by the Coma Recovery Scale-Revised (CRS-R) predicted a survival. However, no reliable markers of significant positive dynamics of consciousness were found. Based on the etiology, anoxic brain injury has the most unfavorable prognosis. For patients with vascular lesions, the first three months after injury have the most important prognostic value. No correlations were found between survival, increased consciousness, and gender. The demographic and clinical characteristics of patients with chronic DOC can be used to predict long-term mortality in patients with chronic disorders of consciousness. Further research should be devoted to finding reliable predictors of recovery of consciousness.

Effect of Retinohypothalamic Tract Dysfunction on Melatonin Level in Patients with Chronic Disorders of Consciousness.

OBJECTIVE: The aim of this study is to compare the secretion level of nocturnal melatonin and the characteristics of the peripheral part of the visual analyzer in patients with chronic disorders of consciousness (DOC). MATERIALS AND METHODS: We studied the level of melatonin in 22 patients with chronic DOC and in 11 healthy volunteers. The fundus condition was assessed using the ophthalmoscopic method. RESULTS: The average level of nocturnal melatonin in patients with DOC differed by 80% from the level of indole in healthy volunteers. This reveals a direct relationship between etiology, the level of consciousness, gaze fixation, coma recovery scale-revised score and the level of melatonin secretion. Examination by an ophthalmologist revealed a decrease in the macular reflex in a significant number of DOC patients, which in turn correlates negatively with the time from brain injury and positively with low values of nocturnal melatonin.

Retrospective analysis of sleep patterns in patients with chronic disorders of consciousness.

Analysis of sleep patterns in patients with chronic disorders of consciousness attracts attention from the perspective of the diagnosis and prognosis of the disease as well as the treatment. Yet, the very existence of normal sleep in patients in a vegetative or minimally conscious state is still a matter of debate. This paper presents a retrospective analysis of overnight polysomnographic records of 40 patients with chronic disorders of consciousness aimed at the possibility of establishing the connection between the degree of impaired consciousness and the presence and organization of polysomnographic graphical elements, associated with stages of sleep in normal individuals. Specialized software based on expert system artificial intelligence was developed to calculate indices and parameters that characterize sleep. It was shown that a remarkably low percentage of patients have a rhythmic change in sleep patterns, what indicates the prevalence of violations of the Sleep-Wake cycle in a vegetative state and minimally conscious state. Sleep spindles were not found in records, however, the absence can originate from the limitations of polysomnographic method applied to patients with severe brain damage. A positive correlation between the rhythmic change of sleep patterns, better outcome and CRS-R scores was confirmed.