Literature Updates from May 2014

Role of Orexin in Respiratory and Sleep Homeostasis During Upper Airway Obstruction in Rats

In upper airway obstruction animals, enhanced orexin secretion, while crucially important for respiratory homeostasis maintenance, is also responsible for chronic partial sleep loss, as well as considerable impairment of energy metabolism and growth.

Sleep and Psychological Health During Early Recovery from Critical Illness: An Observational Study

In this study, the authors attempted to asses patient’s self reported sleep quality in the ICU, after ICU and pre hospital discharge and two to six months after hospital discharge. They wanted to determine if pre-hospital insomnia, experiences in intensive care, quality of life and psychological health are associated with sleep disruption six months after hospital discharge. Two hundred and twenty two patients completed the survey. For more than half of the patients, sleep was a “significant” issue 6 months after ICU treatment. The authors suggested targeting potentially modifiable risk factors in recovery programs.

Sleep Quality and Vigilance Differ Among Inpatient Nurses Based on the Unit Setting and Shift Worked

In this very interesting study, the authors evaluated sleep quality in nurses and evaluate how setting (ICU vs. floor) and time of shift (day vs. night) impacted measures of sleep quality. The authors discovered that a significant number of inpatient nurses have impaired sleep quality, excessive sleepiness, and abnormal fatigue. They stated that these findings might place these nurses at a greater risk of making medical errors and harming patients. They found these problems to be more pronounced in night shift workers and that floor and day shift nurses performed better on some tasks than ICU and night shift nurses. This study is important in that it reminds us that in the ICU, sleep deprivation amongst the staff may also have serious complications that are separate from sleep deprivation in patients.

Sleep Patterns During Long-Term Mechanical Ventilation in Tracheostomized Patients in the ICU: Do They Matter?

In this interesting letter to the editor, the authors comment on Comparison of Sleep Quality With Mechanical Versus Spontaneous Ventilation During Weaning of Critically Ill Tracheostomized Patients that appeared in Crit Care Med (2013;41:1637–1644). The authors agree that poor sleep may affect weaning from mechanical ventilation. However, the authors point out potential limitations in the cross-over design and ways some patients were treated with mechanical ventilation. For those who read the article by Roche-Campo F, this letter will serve to further the discussion on sleep mechanical ventilation and weaning.

Non-Pharmacologic Interventions to Improve the Sleep of Hospitalized Patients: A Systematic Review

This study was not actually an evaluation of ICU patients as the names implies. However, many of the findings will be of interest to the ICU physician. The authors sought to indentify non-pharmacologic interventions that are effective in improving sleep quality and quantity on non-ICU patients. The authors indentified 13 intervention studies with 1154 participants. Unfortunately, there was insufficient to low strength of evidence to recommend any non-pharmacologic therapy. The study does list some interventions that have been tried that the reader may find of interest in some of the less acute ICU patients.

A Review of Normal Values of Infant Sleep Polysomnography

The normal values of obstructive apnea, mixed apnea, and central apnea are well established for neonates and infants. With these normal values, sleep polysomnography study should be routinely used to quantify the severity of breathing disorders during sleep in those neonates at risk for these disorders.

Combination of Symptoms and Oxygen Desaturation Index in Predicting Childhood Obstructive Sleep Apnea

Observable apnea during sleep was an independent positive predictive factor for OSA in children. A child with observable apnea during sleep should be referred to a special sleep laboratory for PSG diagnosis. When the total score is 3 or 4 based on a combination of symptoms and ODI, OSA can be diagnosed and the child should be referred to a sleep pediatrician for appropriate intervention.