Sleep Patterns and Phases of Sleep

Sleep and Sleep Pattern Disturbance

• Sleep is a natural state of unconsciousness allowing the body to rest and recover, making up about one-third of adult life.
• Optimal sleep duration for adults is 7-8 hours.
• Less than 5 hours of sleep significantly increases the risk of heart attack.
• Inadequate sleep increases risks of obesity, heart disease, and type 2 diabetes.
• Sleep supports immune system and mental health.

Phases of Sleep

• NREM Sleep (Non-Rapid Eye Movement): Divided into three stages (N1, N2, N3).
  • Stage N1: Lightest sleep (2-5% of total sleep), lasts a few minutes, characterized by drifting sensations.
  • Stage N2: Light sleep (50% of total sleep) with occasional drifting sensations.
  • Stage N3: Deep, restful, dreamless sleep (10-15% in young adults, less in older adults). Characterized by decreased blood pressure, breathing, and metabolism.
• REM Sleep (Rapid Eye Movement): Occurs every 90 minutes, features dreaming, irregular breathing, and increased heart rate (20-25% of total sleep). Important for stress release and emotional balance.

Sleep Disorders: Insomnia

• Definition: Difficulty falling asleep, staying asleep, or waking too early.
• Types: Initial, intermittent, terminal insomnia; transient, short-term or chronic.
• Prevalence: 10% of adults and 20% of older adults have chronic insomnia.
• Causes: Lifestyle changes, stress, caffeine/alcohol, large meals before sleep, illness.
• Effects: Fatigue, daytime drowsiness, and difficulty with work or daily tasks.

Sedative-Hypnotic Therapy

• Sedatives: Promote relaxation and rest (may not induce sleep).
• Hypnotics: Induce sleep.
• Ideal hypnotic characteristics: Quick onset of natural sleep, proper duration, no hangover effects, and no habit formation.

REM Rebound

• Body compensates for sleep deprivation by spending more time in certain stages of sleep during subsequent sleep periods.
• Caused by sleep deprivation and suppression of REM sleep.
• Characterized by REM rebound (increased intensity/duration of REM sleep) and NREM rebound (body focuses on deep, restorative sleep).
• Purpose: Helps the body recover physically and mentally and restores balance in sleep patterns.

Types of Sedative-Hypnotic Drugs

• Classified into Benzodiazepines and Non-benzodiazepines.

Drug Therapy for Sleep Disturbance: Benzodiazepines

• Commonly used for sedation, sleep induction, anxiety relief, and seizure control.
• Safe with a wide margin between therapeutic and toxic doses.
• Act on GABA-A receptors in the brain.
• Examples: Estazolam, flurazepam, quazepam, temazepam, triazolam.
• Effects: Increase light sleep, decrease deep and REM sleep, leading to tolerance and rebound insomnia.
• Short-term use is recommended.
• Special uses include short-acting benzodiazepines for anesthesia and short procedures, and Lorazepam for pre-surgery anxiety.

Drug Therapy for Sleep Disturbance: Non-Benzodiazepine

• Cause CNS depression to promote sleep, acting as antagonists by blocking orexin receptors and or facilitating GABA action.
• Types: Antihistamines, Tricyclic antidepressants, and Benzodiazepine receptor agonists (Zaleplon, Zopidem, Eszopiclone, Ramelteon, Tasimelteon), Orexin Receptor Antagonists.

Nursing Implications

• Assessment: Check baseline vitals, hepatic disease history.
• Administration: Take before bed or after being in bed with difficulty falling asleep, avoid with heavy meals.
• Monitoring: Watch for morning hangover, adverse effects, and adjust dose as needed. Monitor for gradual discontinuation to avoid withdrawal symptoms.

Therapeutic Outcomes

• Mild sedation.
• Short-term use for sleep induction and maintenance.

Additional Considerations

• Drug Interactions: Alcohol, opioids, and sedatives increase toxic effects, while smoking and rifampin reduce effectiveness.
• Withdrawal: Stopping suddenly can cause withdrawal (anxiety, seizures, delirium).
• Adverse Effects: Common effects can include: drowsiness, hangover, headache, muscle/joint pain, and mental depression. More serious effects include physical dependence, withdrawal symptoms, and/or confusion, and agitation. Older adults or long-term users may be more sensitive to these affects.
• Pregnancy and Breastfeeding: Avoid use, or take with caution during pregnancy and breastfeeding.
• Monitoring: Regular monitoring is necessary for adverse side effects like liver issues, blood dyscrasias or other symptoms.