Neonatal Sleep Neonatal nurseries are the only alternative environment to a human womb that is offered to a preterm infant . The development of these nurseries and its accessories has now opened a new era in the management of these preterm infants .These nurseries by virtue of their sophisticated machines and experienced care givers are now offering a better chance of survival to these fragile infants .These preterm infants are now not only surviving this initial complicated period of their lives but also leading a healthy life comparable to a normal term infant .

Although the preterm infants are profoundly benefited by these nurseries, these infants are also exposed to the various elements of a typical nursery environment .Among these physical elements, the constant lighting, noise, and nursing interventionsare the pertinent ones that may have negative influence on the development and well-being of a preterm infant .These physical elements may cause various negative physiological changes in these infants .Among many, the sleep of a neonate is an essential component that is adversely affected by these environmental factors.

Sleep plays a significant role in growth and functioning of a human . It is essential for repair and healing of body tissues and processing and formation of memory (Zee & Turek, 1999).There is increasing evidence that sleep in infants stimulates various hormonal and physiological processes . This leads to adequate development of brain and other vital organs of an infant's body .Researches also suggest that sleep problems in an infant is more likely to culminate in behavioral, cognitive and emotional problems (Dahl, 1996) .The sleep holds a more premiervalue when it comes to a preterm infant . These preterm infants are still under process of their development; and sleep by virtue of its growth promoting and developmental potentials can be regarded as their essential need .

The sleep of a preterm is influenced by many internal and external elements .The nursery environment in this lieu can have profound influence on a neonate's sleep . As mentioned above, environmental factors like constant lighting, noise, movements and nursing interventions are notorious to adversely affect the sleep of a neonate .This effect on a neonate sleep can result in various short-term and long-term consequences on an infant's behavior and health .

The role of lighting has been well elucidated by a research conducted by NP Mann and colleagues (1986). In their study, the researchers compared the effectsofalternating night and day light vs. . constant lightning on an infant's sleeping pattern and weight gain . In this study, the researchers divided the infants into two groups . One group was exposed to alternating light pattern i.e. more light at daytime as compared to night time while the other group was kept in conventional continuous lighting environment . The researchers concluded that the infants in former group slept more hours on discharge as compared to infants in the latter group . In addition, the researchers also found that the former infants showed much better weight gain as compared to later .This signifies that the constant lighting environment employed in a conventional nursery can have deleterious impact on sleep and health of a neonate.

Similar to the effects of lighting, noise in a nursery environment has also been documented to affect sleep and cause various physiological alternations in a preterm infant .Widespread studies in this regard have concluded that noise can cause disruption of sleep and increased frequency of arousals in a preterm infant . In addition to these, raised noise levels can also elevate cardiac and respiratory rate culminating in arrest of heart and lung functions (Philbin & Klaas, 2000; Sparshott, 1995).

Lastly, newborn care, though very essential, can be a potent disturbing factor of a neonate sleep .Zahr and Balian (1995) have studied the response of newborn to various nursing interventions . They observed significant decrease in blood oxygen levels and increase in heart rate after such interventions .In another study, a positive effect of providing extended periods of non-disturbancewas recorded . This study has indicated that infants who were kept undisturbed for longer period have shown longer bouts of sleep and improvement in overall health (Holditch-Davis et al., 1995).Thus nursing care interventions are also liable to influence a neonate sleep .

Sleep deprivation resulting from above mentioned environmental factors can have various short-term and long-term impacts on a neonate's health . A sleep deprived neonate is more prone to have cardiac rhythms abnormality and cessation of respiration . Literature also points that impaired sleep can lead to decrease in pain perception and may also adversely...

In addition to these short-term effects, emotional, behavioral and cognitive dysfunctions are the pertinent long-term effects that can result from a disturbed sleep among neonates .
Apart from sleep deprivation, these environmental factors can also directly affect neuropsychological development of a preterm infant . There is increasing evidence that factors such as noise can results in deafness, language difficulties and altered brain development .Thus, in order to ensure a better survival and healthy lives for these preterm infants, there is a need to adopt various measures to minimize the effects of these environmental factors .

Many studies have been conducted in order to establish a "best" practice to achieve minimal impact of these environmental factors . For reduction of noise levels in a nursery many recommendation have been brought forth . Strauch and colleagues (1993) have suggested a practice of "quiet hour." In their study the researchers have labeled the last hour of a shift as a quiet hour i.e. bedside talking was reduced, no doctors rounds were allowed, no large equipments were allowed to enter and alarm and crying infants were responded immediately. The researchers concluded that noise levels due to such practices were significantly reduced . It was also observed that approx.85% of infants during this quiet hour were in deep or light sleep as compared to 34% in the control measurements. Thus this study demonstrates that noise levels can be reduced by adopting relatively easy measures.

In regards of reducing noise levels, Saunders and colleagues (1995) have come up with a simple and cheap intervention. Their study concluded that by simply covering the incubator with a blanket can result in significant decrement in noise levels. In another study by Johnson (2003), the reduction of noise levels through staff education was employed. It was found that measurable decrease in noise levels can be achieved by merely educating the staff about the ways to reduce noise. Apart from measuring sound levels, Zahr and Traversey (1995) have tried to objectively assess the response of a preterm infant to reduced noise levels. In their study, the researchers have employed earmuffs to reduce noise intensity while the behavioral and physiological parameters of an infant were observed. It was concluded that the implementation of earmuffs resulted in higher blood oxygen levels and lesser fluctuation in blood oxygen as compared to control group. It was also observed that such infants had less behavioral state changes and increased quiet sleep state. Thus, in summary, noise levels can be reduced by adopting various easy measures like talking less at bedside, decreasing the alarm volume, closing doors when possible and arranging education sessions for the nursing staff. The employment of various interventions like blanket and earmuffs are also very effective in cutting down the noise levels.

Similar to the control of noise, the impact of lighting can also be minimized by adopting some simple measures. Excessive lighting can be reduced by simply decreasing the intensity of light, by employing eye protectors for infants and by covering the incubator. Furthermore, the alternating day and night lighting can also is employed since it has been found beneficial for the sleep and growth of an infant as mentioned above (Mann et al., 1986). Likewise, the negative effects of nursing interventions on a neonate sleep can be overcome by rigorously evaluating the need of a specific procedure before its performance. Apart from emergencies, the nursing interventions should respect the sleep-wake rhythm of an infant and the notion of a strict schedule nursing care should be disregarded. Other measures may include educating mothers regarding the respect of an infant sleep and teaching various techniques to promote sound sleep of a neonate. In addition to these measures, comfortable room temperature levels and various self-reassurance maneuvers like nonnutritive sucking and swaddling can also be employed to ensure a sound sleep of a baby.

In conclusion, the sleep plays a pivotal role in growth and development of an infant.The sleep of an infantis influenced by various factors of a nursery environment. These factors include continuous lighting, noise and various nursing interventions. The disruption of an infant's sleep due to these factors can have deleterious impact on their health and well-being. Various measures as mentioned above should be adopted in order to minimize the impact of these factors and promote sound sleep of neonates. It should be remembered that a sleeping infant is a developing infant and every appropriate measure should be undertaken to maintain the state of an infant's sleep.