Sleep normal physiology
Nearly one third of human life is spent in sleep.Sleep which is broadly divided into two broadly different phases
1.REM-sleep (rapid eye movement sleep)
2.NREM-sleep (non-REM sleep)
In an 8 hour sleep, usually 6-6½ hours are spent in the NREM-sleep while 1½-2 hours are in the REM-sleep. The REM-sleep occurs maximally in the last one-third of the night. The REM-sleep occurs regularly after every 90-100 minutes, with progressive lengthening of each REM period. The ﬁrst REM period typically lasts for less than 10 minutes. Usually, there are 4-5 REM periods in the whole night of sleep.
A younger person may typically need more sleep. The usual sleep duration in newborn children is 16-18 hours/day, with nearly 8-10 hours spent in the REM-sleep. As the age advances, the sleep duration tends to reduce.
Depending on the duration of total sleep, two extremes of ‘normal’ sleeping patterns have been described. 1. Long-sleepers: These persons regularly and habitually sleep for more than 9 hours/night, and this pattern of sleep does not cause any symptoms or dysfunction. 2. Short-sleepers: These persons regularly and habitually sleep for less than 6 hours/night, and this pattern of sleep does not cause any symptoms or dysfunction.
• Insomnia, or the complaint of inadequate sleep, may be subdivided into
• Sleep onset insomnia -Difficulty falling asleep.
• Sleep maintenance insomnia -Frequent or sustained awakenings .
• Sleep offset insomnia -Early morning awakenings .
• Non restorative sleep -Persistent sleepiness/fatigue despite sleep of adequate duration .
• An insomnia complaint lasting one to several nights is termed Transient insomnia and is typically due to situational stress or a change in sleep schedule or environment (e.g., jet lag).
1.Acute insomnia can occur after a change in the sleeping environment (e.g., in an unfamiliar hotel or hospital bed) or before or after a significant life event or anxiety-provoking situation.
2.Drugs and Medications-Caffeine, Alcohol and nicotine, A number of prescribed medications, including antidepressants, and glucocorticoids, can produce insomnia.
3.Movement Disorders –Patients with restless legs syndrome (RLS) complain of creeping dysesthesias deep within the calves or feet associated with an irresistible urge to move the affected limbs; symptoms are typically worse at night.
4.Neurologic Disorders-Neck Or Back Pain, Epilepsy, Parkinson’s Disease, And Migraine
5.Psychiatric Disorders– Depression, Mania, An Anxiety Disorder, Or Schizophrenia.
6. Medical Disorders-Asthma, Cardiac ischemia, Chronic obstructive pulmonary disease, Cystic Fibrosis, Hyperthyroidism, Menopause, Gastroesophageal Reflux, Chronic Renal Failure, Liver Failure.
7. Inadequate sleep hygiene is characterized by a behavior pattern prior to sleep, and/or a bedroom environment(noise,bright light, mobile,television,computer)
1. Regular, daily physical exercises (preferably not in the evening).
2. Minimise daytime napping.
3. Avoid ﬂuid intake and heavy meals just before bedtime.
4. Avoid caffeine intake (e.g. tea, coffee, cola drinks) before sleeping hours.
5. Avoid regular use of alcohol (especially avoid use of alcohol as a hypnotic for promoting sleep).
6. Avoid reading or watching television while in bed.
7. Sleep in a dark, quiet, and comfortable environment.
8. Regular times for going to sleep and waking-up
9. Try relaxation techniques.
10.Treatment of the underlying physical and/or psychiatric disorder, if present,