Disordered Consciousness or Disordered Wakefulness? The Importance of Prolonged Polysomnography for the Diagnosis, Drug Therapy, and Rehabilitation of an Unresponsive Patient With Brain Injury

Abstract

Disorders of consciousness may follow brain injury, due to impairments of wakefulness and/or awareness. Polysomnography can identify elements that may be ascribed to impairments of specific neuroanatomical areas. Recognizing which impairments affect each patient is crucial for diagnosis, prognosis, and to select an appropriate therapy. We present a pediatric case of insufficient wakefulness in a patient with severe disability following a pilocytic astrocytoma. Polysomnography was crucial for diagnosis, as it detected a well-structured pattern with daytime sleep initiations in the REM sleep phase. Treatment with modafinil was successful, as confirmed by polysomnography, leading to partial recovery of the patient's consciousness and communication ability. We suggest that polysomnography is a useful diagnostic tool to direct the pharmacotherapy and rehabilitation of states of reduced consciousness.

Sleep Treatments in Disorders of Consciousness: A Systematic Review

“…The majority of the included studies were case reports ( n = 5); [ 46 , 47 , 48 , 49 , 50 ], one study adopted a cross-sectional design [ 51 ], and one was a retrospective pilot study [ 52 ].…”

“…Two articles focused on treatments for sleep-related breathing disorders [ 49 , 50 ], namely central apnea and obstructive apnea, respectively. The other five included articles examined different treatments to improve circadian rhythm regulation and the sleep–wake cycle, including extreme fragmentation of nocturnal sleep and excessive sleepiness ( n = 3; [ 47 , 51 , 52 ]) and alterations in sleep dynamics ( n = 2; [ 46 , 48 ]).…”

“…As for treatments, three studies adopted pharmacological interventions [ 47 , 49 , 52 ], one study described an environmental intervention [ 51 ], one study relied on the use of a device to treat sleep disorder [ 50 ], while two studies focused on the use of brain stimulation [ 46 , 48 ]. In what follows, interventions are presented for each category of sleep disorders (i.e., sleep-related breathing disorders and sleep rhythm dysregulation); see also Table 1 for the main features of the studies included in this review.…”

“…Two studies adopted a pharmacological treatment with Modafinil [ 47 , 52 ] for sleep rhythm normalization. Specifically, in a retrospective pilot study [ 52 ] on 24 patients diagnosed with VS or MCS, Modafinil in addition to standard therapies had beneficial effects in treating excessive sleepiness and improving cognition.…”

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

“…Yet, the very existence of normal sleep in patients in a vegetative or minimally conscious state is still a matter of debate [ 13 ]. Polysomnography (PSG) as a method of sleep study is recognized worldwide and in some cases is crucial for diagnosis and confirming of the success of therapy [ 14 ], appeared to have good correlation with CRS-R score [ 15 ]. However, PSG, being the most affordable method for assessing cortical activity, does not demonstrates specificity in determining and predicting consciousness [ [16] , [17] , [18] , [19] , [20] ].…”