Caroline Arbour

Regional Cerebral Blood Flow during Wakeful Rest in Older Subjects with Mild to Severe Obstructive Sleep Apnea.

OBJECTIVES To evaluate changes in regional cerebral blood flow (rCBF) during wakeful rest in older subjects with mild to severe obstructive sleep apnea (OSA) and healthy controls, and to identify markers of OSA severity that predict altered rCBF. DESIGN High-resolution (99m)Tc-HMPAO SPECT imaging during wakeful rest. SETTING Research sleep laboratory affiliated with a University hospital. PARTICIPANTS Fifty untreated OSA patients aged between 55 and 85 years, divided into mild, moderate, and severe OSA, and 20 age-matched healthy controls. INTERVENTIONS N/A. MEASUREMENTS Using statistical parametric mapping, rCBF was compared between groups and correlated with clinical, respiratory, and sleep variables. RESULTS Whereas no rCBF change was observed in mild and moderate groups, participants with severe OSA had reduced rCBF compared to controls in the left parietal lobules, left precentral gyrus, bilateral postcentral gyri, and right precuneus. Reduced rCBF in these regions and in areas of the bilateral frontal and left temporal cortex was associated with more hypopneas, snoring, hypoxemia, and sleepiness. Higher apnea, microarousal, and body mass indexes were correlated to increased rCBF in the basal ganglia, insula, and limbic system. CONCLUSIONS While older individuals with severe obstructive sleep apnea (OSA) had hypoperfusion in the sensorimotor and parietal areas, respiratory variables and subjective sleepiness were correlated with extended regions of hypoperfusion in the lateral cortex. Interestingly, OSA severity, sleep fragmentation, and obesity correlated with increased perfusion in subcortical and medial cortical regions. Anomalies with such a distribution could result in cognitive deficits and reflect impaired vascular regulation, altered neuronal integrity, and/or undergoing neurodegenerative processes.

Impact of the Implementation of the Critical-care Pain Observation Tool (cpot) on Pain Management and Clinical Outcomes in Mechanically Ventilated Trauma Intensive Care Unit Patients: A Pilot Study

This pilot study was aimed to explore the impact of the implementation of the Critical-Care Pain Observation Tool on pain management and clinical outcomes in mechanically ventilated trauma intensive care unit patients. Thirty medical files were reviewed in this preexperimental before-and-after study design. Pain assessments and identification of pain episodes were more frequent postimplementation of the tool. Although fewer analgesics were administered during the postimplementation phase, these interventions were found to be more efficient than those of the preimplementation phase. Moreover, during the postimplementation phase, a lower number of complications were observed.

Detecting pain in traumatic brain-injured patients with different levels of consciousness during common procedures in the ICU: typical or atypical behaviors?

Purpose:Pain behaviors such as grimacing and muscle rigidity are recommended for pain assessment in nonverbal populations. However, these behaviors may not be appropriate for critically ill patients with a traumatic brain injury (TBI) depending on their level of consciousness (LOC). This study aimed to validate the use of behaviors for assessing pain of critically ill TBI adults with different LOC. Methods:Using a repeated measure within subject design, participants (N=45) were observed for 1 minute before (baseline), during, and 15 minutes after 2 procedures: (1) noninvasive blood pressure: NIBP (non-nociceptive); and (2) turning (nociceptive). A behavioral checklist combining 50 items from existing pain assessment tools and video recording were used to describe participants’ behaviors. Intrarater and interrater agreements of observed behaviors were also examined. Results:Overall, pain behaviors were observed more frequently during turning (median=4; T=−5.336; P⩽0.001) than at baseline (median=1), or during noninvasive blood pressure (median=0). TBI patients’ pain behaviors were mostly “atypical” and included uncommon responses such as flushing, sudden eye opening, eye weeping, and flexion of limbs. These behaviors were observed in ≥25.0% of TBI participants during turning independent of their LOC, and in 22.2% to 66.7% of conscious participants who reported the presence of pain. Agreements were >92% among and between the 2 raters. Conclusions:This study support previous findings that critically ill TBI patients could exhibit atypical behaviors when exposed to nociceptive procedures. As such, use of current recommended pain behaviors as part of standardized scales may not be optimal for assessing the analgesic needs of this vulnerable group.

Sleep and wake disturbances following traumatic brain injury

Traumatic brain injury (TBI) is a major health concern in industrialised countries. Sleep and wake disturbances are among the most persistent and disabling sequelae after TBI. Yet, despite the widespread complaints of post-TBI sleep and wake disturbances, studies on their etiology, pathophysiology, and treatments remain inconclusive. This narrative review aims to summarise the current state of knowledge regarding the nature of sleep and wake disturbances following TBI, both subjective and objective, spanning all levels of severity and phases post-injury. A second goal is to outline the various causes of post-TBI sleep-wake disturbances. Globally, although sleep-wake complaints are reported in all studies and across all levels of severity, consensus regarding the objective nature of these disturbances is not unanimous and varies widely across studies. In order to optimise recovery in TBI survivors, further studies are required to shed light on the complexity and heterogeneity of post-TBI sleep and wake disturbances, and to fully grasp the best timing and approach for intervention.

Are NREM sleep characteristics associated to subjective sleep complaints after mild traumatic brain injury

INTRODUCTION Sleep complaints are common after mild traumatic brain injury (mTBI). While recent findings suggest that sleep macro-architecture is preserved in mTBI, features of non-rapid eye movement (NREM) sleep micro-architecture including electroencephalography (EEG) spectral power, slow waves (SW), and sleep spindles could be affected. This study aimed to compare NREM sleep in mTBI and healthy controls, and explore whether NREM sleep characteristics correlate with sleep complaints in these groups. METHODS Thirty-four mTBI participants (mean age: 34.2 ± 11.9 yrs; post-injury delay: 10.5 ± 10.4 weeks) and 29 age-matched controls (mean age: 32.4 ± 8.2 yrs) were recruited for two consecutive nights of polysomnographic (PSG) recording. Spectral power was computed and SW and spindles were automatically detected in three derivations (F3, C3, O1) for the first three sleep cycles. Subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). RESULTS mTBI participants reported significant poorer sleep quality than controls on the PSQI and showed significant increases in beta power during NREM sleep at the occipital derivation only. Conversely, no group differences were found in SW and spindle characteristics. Interestingly, changes in NREM sleep characteristics were not associated with mTBI estimation of sleep quality. CONCLUSIONS Compared to controls, mTBI were found to have enhanced NREM beta power. However, these changes were not found to be associated with the subjective evaluation of sleep. While increases in beta bands during NREM sleep may be attributable to the occurrence of a brain injury, they could also be related to the presence of pain and anxiety as suggested in one prior study.

Evaluation of the Preliminary Effectiveness of Hand Massage Therapy on Postoperative Pain of Adults in the Intensive Care Unit after Cardiac Surgery: A Pilot Randomized Controlled Trial

Although many intensive care unit patients experience significant pain, very few studies explored massage to maximize their pain relief. This study aimed to evaluate the preliminary effects of hand massage on pain after cardiac surgery in the adult intensive care unit. A pilot randomized controlled trial was used for this study. The study was conducted in a Canadian medical-surgical intensive care unit. Forty adults who were admitted to the intensive care unit after undergoing elective cardiac surgery in the previous 24 hours participated in the study. They were randomly assigned to the experimental (n = 21) or control (n = 19) group. The experimental group received a 15-minute hand massage, and the control group received a 15-minute hand-holding without massage. In both groups the intervention was followed by a 30-minute rest period. The interventions were offered on 2-3 occasions within 24 hours after surgery. Pain, muscle tension, and vital signs were assessed. Pain intensity and behavioral scores were decreased for the experimental group. Although hand massage decreased muscle tension, fluctuations in vital signs were not significant. This study supports potential benefits of hand massage for intensive care unit postoperative pain management. Although larger randomized controlled trials are necessary, this low-cost nonpharmacologic intervention can be safely administered.

Behavioral and physiologic indicators of pain in nonverbal patients with a traumatic brain injury: an integrative review.

The use of behavioral and physiologic indicators is recommended for pain assessment in nonverbal patients. Traumatic brain injuries (TBI) can lead to neurologic changes and affect the way patients respond to pain. As such, commonly used indicators of pain may not apply to TBI patients. This study aimed to review the literature about behavioral/physiologic indicators of pain in nonverbal TBI patients. An integrative review method was used. Medline (from 1948 to June 2011), Cinahl, and Cochrane databases were searched using any combination of the terms brain injury, behavioral indicators, behavioral scale, physiologic indicators, pain, pain assessment, and pain measurement. All articles reporting expert opinion or original data about the validity of behavioral and/or physiologic indicators of pain in TBI patients were considered. For each article included, the quality of findings/clinical recommendations was graded independently by two raters using SORT taxonomy. Eight papers were reviewed. Overall, TBI patients seemed to present a wider range of behavioral reactions to pain than other adult populations. In addition to the commonly observed grimace, agitation, and increased muscle tension, 14%-72% of TBI patients showed raising eyebrows, opening eyes, weeping eyes, and absence of muscle tension when exposed to pain. Those atypical reactions appeared to be present only in the acute phase of TBIs recovery. Similarly to other populations, vital signs were identified as potential indicators of pain in TBI patients. Further research studying TBI patients and considering changes in level of consciousness, location/severity of brain injury, and administration of analgesic/sedative is needed. Until then, nurses should follow the current clinical recommendations.

Parallel recovery of consciousness and sleep in acute traumatic brain injury

Objective: To investigate whether the progressive recuperation of consciousness was associated with the reconsolidation of sleep and wake states in hospitalized patients with acute traumatic brain injury (TBI). Methods: This study comprised 30 hospitalized patients (age 29.1 ± 13.5 years) in the acute phase of moderate or severe TBI. Testing started 21.0 ± 13.7 days postinjury. Consciousness level and cognitive functioning were assessed daily with the Rancho Los Amigos scale of cognitive functioning (RLA). Sleep and wake cycle characteristics were estimated with continuous wrist actigraphy. Mixed model analyses were performed on 233 days with the RLA (fixed effect) and sleep-wake variables (random effects). Linear contrast analyses were performed in order to verify if consolidation of the sleep and wake states improved linearly with increasing RLA score. Results: Associations were found between scores on the consciousness/cognitive functioning scale and measures of sleep-wake cycle consolidation (p < 0.001), nighttime sleep duration (p = 0.018), and nighttime fragmentation index (p < 0.001). These associations showed strong linear relationships (p < 0.01 for all), revealing that consciousness and cognition improved in parallel with sleep-wake quality. Consolidated 24-hour sleep-wake cycle occurred when patients were able to give context-appropriate, goal-directed responses. Conclusions: Our results showed that when the brain has not sufficiently recovered a certain level of consciousness, it is also unable to generate a 24-hour sleep-wake cycle and consolidated nighttime sleep. This study contributes to elucidating the pathophysiology of severe sleep-wake cycle alterations in the acute phase of moderate to severe TBI.

An exploratory study of the bilateral bispectral index for pain detection in traumatic-brain-injured patients with altered level of consciousness.

ABSTRACT Introduction: Many patients with a traumatic brain injury (TBI) cannot communicate because of altered level of consciousness. Although observation of pain behaviors (e.g., frowning) is recommended for pain assessment in nonverbal populations, they are attenuated and sometimes even suppressed in patients with TBI receiving high doses of sedatives. This study explored the potential utility of the bilateral bispectral index system (BIS) for pain detection in critically ill adults with TBI and altered level of consciousness. Methods: Using a repeated measure within-subject design, participants (N = 25) were observed for 1 minute before (baseline), during, and 15 minutes after two procedures: (a) noninvasive blood pressure (nonnociceptive) and (b) turning (nociceptive). At each assessment, BIS indexes (0–100) of the right (R) and left (L) hemispheres and pain behaviors were documented. Results: Compared with baseline, significant median increases (p ⩽ .05) in BIS-R (+4.93%) and BIS-L (+8.43%) and in the frequency of pain behaviors (+3.00) were observed during turning but not noninvasive blood pressure. Interestingly, increases in BIS-R were more pronounced in participants with left-sided TBI (+17.23%, p = .021) than those with right-sided TBI (+3.01%). BIS-R fluctuations in participants with left-sided TBI were also positively correlated (r s = .986, p ⩽ .001) with the frequency of pain behaviors observed during turning. Conclusions: Overall, only increases in BIS-R were correlated with participants’ pain behaviors and in those with left-sided TBI exclusively. Although further research is needed, our findings support the potential use of the bilateral BIS for pain detection in nonverbal patients with TBI who cannot behaviorally respond to pain, but only when they have a left-sided injury.

Response to the letter from Professor Helena Hachul and colleagues

Thank you for your interest regarding our recent paper entitled: “Individuals with pain need more sleep in the early stage of mild traumatic brain injury (mTBI)” published in Sleep Medicine [1]. Overall, we found that 29% of recovering mTBI individuals express an increased need for sleep (suggesting a subgroup effect) at one month post-trauma, particularly in the context of unrelieved acute pain (1). The suggested hypothesis of increased sleep needs as a compensatory mechanism for pain after TBI is a very interesting one. However, due to our study design and the lack of evidencebased data in the TBI literature, we refrained from including it in our paper. Still, we fully agree with your suggestion that an increased need for sleep and napping in early recovering TBI with pain may underlie more complex physiological processes (eg, inflammatory, immune, endocrine, chemical) related to brain recovery. Future studies on mTBI should undoubtedly try to unravel the influence or role of sleep restorative properties and their mutual influence on positive or negative TBI recovery. The following questions would be a good starting point: