Sleep Study (Polysomnography) By Hatem Ezz eldin Hassen MD Consultant of Phoniatrics KFHJ

DIAGNOSIS History: Snoring Obstructive episodes Arousals /nocturnal choking Excessive daytime sleepiness Abnormal motor movements Morning headaches Nasal obstruction Weight gain Drugs: alcohol intake Cardiovascular symptoms Respiratory symptoms Thyroid symptoms Social history

Examination General appearance WeightHeight Blood pressure Craniofacial morphology Nasal airway Tongue size, Soft palate/uvula/tonsils Nasopharynx - adenoids / polyps / cyst / tumor Hypopharynx-lingual tonsils/vallecula, epiglottic or supra-glottic cysts / tumour Larynx-vocal folds mobility

Investigations:   To assess the patient's general condition   To differentiate between simple snoring and sleep apnea and determine the presence, type and severity of any apneas or hypopneas and,   To assess the site of airway obstruction obstruction

Investigations   Polysomnography  Lateral cephalometry  Naso-optic fibroscopy (Muller’s maneuver)  Sleep nasendoscopy  Computed tomography (CT)  Magnetic resonance imaging (MRI)  Acoustic reflection technique  Pharyngeal manometry  Acoustic analysis of snoring sounds

*is the gold standard investigation in the diagnosis of OSAS and other forms of sleep related disorders. * multiple simultaneous recording of physiologic measures during sleep. Polysomnography

PHYSIOLOGY OF SLEEP Normal sleep entails a cyclical progression from non rapid eye movement sleep (N-REM) to rapid eye movement sleep (REM) with a periodicity of minutes. Normal sleep entails a cyclical progression from non rapid eye movement sleep (N-REM) to rapid eye movement sleep (REM) with a periodicity of minutes. During N-REM sleep, subjects pass through 4 stages which represent progressively deeper sleep states. During N-REM sleep, subjects pass through 4 stages which represent progressively deeper sleep states. During REM sleep, increased movements and EEG activity occurs with characteristic eye movements. Dreaming & Obstructive episodes are likely to occur during REM sleep During REM sleep, increased movements and EEG activity occurs with characteristic eye movements. Dreaming & Obstructive episodes are likely to occur during REM sleep A normal young adult would spend 5 % of the night in stage 1, 45 % in stage 2, 15 % in stage 3, 10 % in stage 4, and 25 % in REM sleep (Baker, 1986). A normal young adult would spend 5 % of the night in stage 1, 45 % in stage 2, 15 % in stage 3, 10 % in stage 4, and 25 % in REM sleep (Baker, 1986).

PHYSIOLOGY OF SLEEP

Polysomnography   Electroencephalogram (EEG).   Submental electromyogram (EMG).   Electro – oculogram (EOG) : These three measurement are needed for sleep staging and allow differentiation between sleep and wakefulness.   Oxygen saturation (P O2 ): by Modern pulse oximeters   Electrocardiogram (ECG) : To monitor apnea associated arrhythmias.   Nasal and oral airflow: airflow is usually detected using heat sensitive thermoisters. These are not able to quantify airflow but simply detect its presence or absence. Absence of airflow for greater than 10 sec. Will be counted as an apnea.   Chest and abdominal movement: patients wear an elasticized belt around the chest and abdomen into witch are incorporated strain gauges that measure changes in circumference. This information allows differentiation between central and obstructive apnea.   Anterior tibialis EMG: Allows the diagnosis of “periodic movements during sleep”   Sleeping position detector :

Sleep Lab

A: Central apnea B: Obstructive apnea A B Polysomnography

  Snoring: is a noise generated from the upper airway due to partial airway obstruction   An apnea: is the cessation of airflow at the nostrils and mouth for at least 10 seconds.   The apnea index (AI): is the number of apneas per hour of sleep.   Hypopnea: a decrease in airflow associated with oxygen desaturation   The apnea Hypopnea index (AHI): apneas + Hpopneas per hour of sleep  the total number of obstructive apneas, hypopneas, and central apneas per hour.  The respiratory disturbance index (RDI): the total number of obstructive apneas, hypopneas, and central apneas per hour.   The sleep apnea syndrome (SAS): 30 or more apneic episodes during a 7-hour period of sleep or an apnea index equals to or greater than 5.   The American sleep association grades sleep apnea as follows: Mild: (AHI 5-15) (AHI 5-30) Moderate: (AHI 5-30) Severe: (AHI >30). Sleep Related Breathing Disorders - Definitions

  Obstructive sleep apnea: The cessation of airflow in the presence of continued respiratory effort. Due to Upper airway obst.   Central sleep apnea: No flow of air at the nose or mouth associated with a cessation of all respiratory effort. These patients may or may not snore. Heart failure, frontal lobe damage or brain- stem lesions. Often no apparent cause, and it is thought to be related to instability of the respiratory control mechanisms.   Mixed apnea: this usually begins as a central apnea with no airflow or respiratory effort followed by increasingly forceful respiratory efforts again with no airflow until airway clears. Obstructive apnea is more common than central apnea though any individual may demonstrate one or more of the above forms of apneas during a night's sleep.

Upper Airway Resistance Syndrome   Episodes of marked partial upper airway obstruction but, no complete obst. of the airway. They are able to maintain their oxygen saturation but need so much respiratory effort to overcome the partial obstruction that they induce frequent micro arousals  They usually have symptoms similar to those with OSA.  Treatment of UARS is similar to that of OSA; the use of CPAP usually is effective.  Main difference between UARS and OSA is the there is no hypoxia related to UARS.

Polysomnogram After complete sleep study the following information is scored: Lights out Lights out Sleep Latency – from lights out to onset of sleep Sleep Latency – from lights out to onset of sleep Sleep Stages Sleep Stages Non-REM – N1, N2, N3 Non-REM – N1, N2, N3 REM REM Sleep Efficiency – percentage of time asleep Sleep Efficiency – percentage of time asleep Respiratory Events Respiratory Events Leg Movements Leg Movements Arousals Arousals Heart Rhythms Heart Rhythms Snoring intensity Snoring intensity Lights on Lights on Quality of patient’s sleep compared to baseline Quality of patient’s sleep compared to baseline

Scoring Respiratory Events Apnea – when all of the following criteria are met 1) There is a drop in the peak thermal sensor excursion by >90% of baseline 2) The duration of the event lasts at least 10 seconds 3) At least 90% of the event’s duration meets the amplitude criteria for apnea 4) Classified as: obstructive, central, or mixed based on respiratory effort Hypopnea – when all of the following are met 1) The nasal pressure signal excursion drops by 30% of baseline 2) The duration of this drop occurs for a period of at least 10 seconds 3) There is a 4% desaturation from pre-event baseline 4) At least 90% of the event’s duration meets the amplitude criteria The AASM Manual for the Scoring of Sleep and Associated Events, 2007

Hypercapnic CSA Impaired Central Drive ("Won’t Breathe"): 1-Tumors or trauma-induced lesions to brainstem Impaired Central Drive ("Won’t Breathe"): 1-Tumors or trauma-induced lesions to brainstem 2-congenital central hypoventilation syndrome (Ondine curse) 2-congenital central hypoventilation syndrome (Ondine curse) 3-opioid-induced CSA 3-opioid-induced CSA 4- OHS 4- OHS Impaired Respiratory Motor Control ("Can’t Breathe") Impaired Respiratory Motor Control ("Can’t Breathe") 1-myasthenia gravis 1-myasthenia gravis 2-amyotrophic lateral sclerosis 2-amyotrophic lateral sclerosis 3-post-polio syndrome 3-post-polio syndrome 4-myopathies 4-myopathies 5-Chest wall syndromes such as kyphoscoliosis 5-Chest wall syndromes such as kyphoscoliosis

PSG Indications: Nonrespiratory Disorders A PSG preceding an MSLT is indicated for evaluation of suspected narcolepsy or to help differentiate narcolepsy from. A PSG preceding an MSLT is indicated for evaluation of suspected narcolepsy or to help differentiate narcolepsy from idiopathic hypersomnia. PSG is indicated for evaluation of suspected periodic limb movement disorder but NOT the restless legs syndrome (RLS; a clinical diagnosis). PSG is indicated for evaluation of suspected periodic limb movement disorder but NOT the restless legs syndrome (RLS; a clinical diagnosis). A PSG is indicated to evaluate (1) nocturnal behavior possibly due to, (2)atypical behavior (frequent episodes each night,stereotypic behavior, or behavior unusual for age), (3) that has resulted in injury to the patient or others A PSG is indicated to evaluate (1) nocturnal behavior possibly due to seizures, (2)atypical parasomnia behavior (frequent episodes each night,stereotypic behavior, or behavior unusual for age), (3) nocturnal behavior/parasomnia that has resulted in injury to the patient or others

Portable Monitoring for OSA in Adults Types of Monitoring Devices Type 1 – in sleep center, attended, overnight polysomnogram Type 2 – record same variables as type 1, unattended (at home) Type 3 – evaluate four physiologic parameters – not sleep respiratory movement and airflow heart rate arterial oxygen saturations (snoring), (position) Type 4 – evaluate one or two parameters (saturation and airflow)

Approach to Reading the PSG Before the PSG is read, a review of the clinical history with special attention to symptoms of sleep apnea, narcolepsy, RLS, and medications is very useful. Before the PSG is read, a review of the clinical history with special attention to symptoms of sleep apnea, narcolepsy, RLS, and medications is very useful. The presence of underlying lung disease may help explain a low awake arterial oxygen saturation (SaO2) or low baseline sleeping SaO2. The presence of underlying lung disease may help explain a low awake arterial oxygen saturation (SaO2) or low baseline sleeping SaO2. A clinical history of pacemaker insertion or known atrial fibrillation is also very helpful in providing a useful interpretation of ECG findings. A clinical history of pacemaker insertion or known atrial fibrillation is also very helpful in providing a useful interpretation of ECG findings. All digital PSG systems have a view that shows graphical summary information of the entire night. It is often useful to look at the big picture before going through the data in smaller time windows. All digital PSG systems have a view that shows graphical summary information of the entire night. It is often useful to look at the big picture before going through the data in smaller time windows.

Tips for the clinician : The clinician should recognize that many patients with significant OSA do not complain of daytime sleepiness. A history of snoring and gasping would suggest a PSG is indicated. It should also be noted that some patients with OSA complain of insomnia. A PSG for PAP titration is the standard procedure to select a level of pressure for treatment. The titration can be performed on a separate night after a diagnostic PSG or during the second part of the night during a split (partial night) study.

POLYSOMNOGRAPHY Indications of Split Study: (1) AHI > 40 /hr with at least 2 hours of monitoring, (1) AHI > 40 /hr with at least 2 hours of monitoring, (2) AHI of 20 to 40 with special clinical circumstances such as severe desaturation or arrhythmia thought due to OSA (2) AHI of 20 to 40 with special clinical circumstances such as severe desaturation or arrhythmia thought due to OSA (3) at least 3 hours remain for the PSG titration. (3) at least 3 hours remain for the PSG titration. Indications of PSG Repeat:  Time for CPAP titration is < 3 hours  If the patient is being treated on CPAP and is NOT doing well, a repeat PSG study on CPAP is indicated.  PSG is also indicated if a patient on CPAP gains > 10% of body weight to determine whether the pressure is adequate.

DD of OSAS Dyspnea due to pulmonary edema Dyspnea due to pulmonary edema Idiopathic hypersomnia Idiopathic hypersomnia Nocturnal panic attacks Nocturnal panic attacks Obesity-hypoventilation syndrome (pickwickian syndrome Obesity-hypoventilation syndrome (pickwickian syndrome Simple snoring Simple snoring Asthma Asthma Chronic Obstructive Pulmonary Disease Chronic Obstructive Pulmonary Disease Depression Depression Gastroesophageal Reflux Disease Gastroesophageal Reflux Disease Hypothyroidism Hypothyroidism Narcolepsy Narcolepsy Periodic Limb Movement Disorder Periodic Limb Movement Disorder

Narcolepsy Classic tetrad of Classic tetrad of 1- excessive daytime sleepiness (EDS), 2- cataplexy, 1- excessive daytime sleepiness (EDS), 2- cataplexy, 3- hypnagogic hallucinations, 4- sleep paralysis. 3- hypnagogic hallucinations, 4- sleep paralysis. Narcolepsy is thought to result from genetic predisposition, abnormal neurotransmitter functioning and sensitivity, and abnormal immune modulation. Narcolepsy is thought to result from genetic predisposition, abnormal neurotransmitter functioning and sensitivity, and abnormal immune modulation. Diagnosis Diagnosis The combination of an overnight polysomnogram (PSG) & a multiple sleep latency test (MSLT) showing sleep latency 8 minutes or less and 2 or more sleep-onset random eye movement (REM) periods strong suggests narcolepsy The combination of an overnight polysomnogram (PSG) & a multiple sleep latency test (MSLT) showing sleep latency 8 minutes or less and 2 or more sleep-onset random eye movement (REM) periods strong suggests narcolepsy An alternative criterion is a cerebrospinal fluid hypocretin level of 110 pg/mL or less. An alternative criterion is a cerebrospinal fluid hypocretin level of 110 pg/mL or less.

Restless Legs Syndrome Periodic leg movements of sleep [PLMS]). PLMS are characterized by involuntary, forceful dorsiflexion of the foot lasting seconds and occurring every seconds throughout sleep. Periodic leg movements of sleep [PLMS]). PLMS are characterized by involuntary, forceful dorsiflexion of the foot lasting seconds and occurring every seconds throughout sleep. excessive daytime somnolence excessive daytime somnolence sleep disturbances, daytime fatigue, and involuntary, repetitive, periodic, jerking limb movements (either while the patient is asleep or while he or she is awake and at rest). A positive family history also aids in the diagnosis of RLS, especially in children. sleep disturbances, daytime fatigue, and involuntary, repetitive, periodic, jerking limb movements (either while the patient is asleep or while he or she is awake and at rest). A positive family history also aids in the diagnosis of RLS, especially in children.

Thank You

Polysomnography Measurements Pulse ox, EEG, EOG, ECG, EMG, oral/nasal airflow, respiratory effort, limb/body movements Pulse ox, EEG, EOG, ECG, EMG, oral/nasal airflow, respiratory effort, limb/body movementsDefinitions Apnea – lack of ventilation for ≥10 sec with signs of arousal Apnea – lack of ventilation for ≥10 sec with signs of arousal Hypopnea – decrease in respiratory movement with a drop in O 2 sat or with signs of arousal Hypopnea – decrease in respiratory movement with a drop in O 2 sat or with signs of arousal AHI or RDI =(Apneas + Hypopneas)/hours of sleep AHI or RDI =(Apneas + Hypopneas)/hours of sleep Important parameters RDI RDI Lowest O 2 saturation Lowest O 2 saturation Number of desaturations below 90% Number of desaturations below 90% Length of time below 90% Length of time below 90%

Medical Management CPAP Pressure must be individually titrated Pressure must be individually titrated Compliance is as low as 50% Compliance is as low as 50% Air leakage, eustachian tube dysfunction, noise, mask discomfort, claustrophobia Air leakage, eustachian tube dysfunction, noise, mask discomfort, claustrophobia

PORTABLE MONITORING (HOME SLEEP TESTING, OUT OF CENTER SLEEP TESTING) The tests are not always performed in the home ;hence, the terms HST or PM are not ideal but are used in much of the literature on this subject. The tests are not always performed in the home ;hence, the terms HST or PM are not ideal but are used in much of the literature on this subject. In the past, PM has been used to diagnose OSA in settings in which access to PSG is limited or delayed. In the past, PM has been used to diagnose OSA in settings in which access to PSG is limited or delayed. The original classification used “level I, II, III, and IV” to refer to different classes of monitoring but currently the terminology is “type 1, 2, 3, and 4.” The original classification used “level I, II, III, and IV” to refer to different classes of monitoring but currently the terminology is “type 1, 2, 3, and 4.” The Centers for Medicare and Medicaid Services (CMS) has a different classification for monitoring The CMS terminology defines the respiratory disturbance index (RDI) as the total number of apneas and hypopneas per hour of monitoring time. Therefore, the index determined by PM (no EEG) would be an RDI using the CMS definition. CMS also refers to PM as HST. The Centers for Medicare and Medicaid Services (CMS) has a different classification for monitoring The CMS terminology defines the respiratory disturbance index (RDI) as the total number of apneas and hypopneas per hour of monitoring time. Therefore, the index determined by PM (no EEG) would be an RDI using the CMS definition. CMS also refers to PM as HST.

Medical Management BiPAP BiPAP Useful when > 6 cm H2O difference in inspiratory and expiratory pressures Useful when > 6 cm H2O difference in inspiratory and expiratory pressures No objective evidence demonstrates improved compliance over CPAP No objective evidence demonstrates improved compliance over CPAP

Portable Monitoring for OSA in Adults Limitations of Type 3 devices Apnea Hypopnea Index – abnormal breathing events by recording time as sleep can not be recorded Apnea Hypopnea Index – abnormal breathing events by recording time as sleep can not be recorded Unless the patient was sleeping the entire recording time, the AHI calculated by a portable monitor will likely be lower than an attended polysomnogram Unless the patient was sleeping the entire recording time, the AHI calculated by a portable monitor will likely be lower than an attended polysomnogram Can not distinguish sleep stages Can not distinguish sleep stages

Friedman algorithm for treatment Mild (AHI 5-15) Mild (AHI 5-15) Symptomless: behavior modification Symptomless: behavior modification Symptoms: behavior, device, consider surgery Symptoms: behavior, device, consider surgery Moderate (AHI 15-30) Moderate (AHI 15-30) Symptomless: behavior, device Symptomless: behavior, device Symptoms: device, consider surgery for device failures Symptoms: device, consider surgery for device failures Severe (AHI >30) Severe (AHI >30) Device, consider surgery as adjunct, refer for bariatric surgery BMI>40, consider tracheostomy Device, consider surgery as adjunct, refer for bariatric surgery BMI>40, consider tracheostomy

Sleep disordered breathing (SDB) is characterized by repetitive episodes of diminished and cessation of breathing during nocturnal sleep (Block et al, 1980). The spectrum of SDB ranges from chronic snoring and upper airway resistance syndrome to obstructive sleep apnea (Guilleminault et al., 1991).

Grades of Sleep Apnea Severity The severity of OSA was determined by the (AHI) The severity of OSA was determined by the (AHI) Mild: AHI 5-15 Mild: AHI 5-15 Moderate: AHI Moderate: AHI Severe: AHI greater than 30 Severe: AHI greater than 30

Obstructive Sleep Apnea Respiratory Disturbance Index (RDI) – no longer used  apneas, hypopneas, respiratory related arousals Apnea-Hypopnea Index (AHI)  total number of respiratory events / hours of sleep Severity of OSA defined by the AHI: < 5 – not sleep apnea 5 – 15 – MILD 15 – 30 – MODERATE > 30 – SEVERE

Diagnosis of the site of upper airway obstruction: Muller’s Maneuver Muller’s Maneuver Sleep endoscopy Sleep endoscopy Fluoroscopy Fluoroscopy Manometry Manometry Cephalometrics Cephalometrics Dynamic CT scanning and MRI scanning Dynamic CT scanning and MRI scanning Mallampati Airway Classification Mallampati Airway Classification Friedman Classification Friedman Classification

The report can include a measure of the sleep onset time (latency) and the proportion of sleep time spent in each of the sleep stages. Obstructive sleep apnea is characterized by absence of airflow at the nose and mouth despite the presence of respiratory effort (thoracic and abdominal). is caused by a structural narrowing of the upper airway that becomes manifest when muscular tone diminishes during sleep central sleep apnea, the patient’s airway is normal, but airflow is absent because of an absence of respiratory effort. Central apnea is caused by a neurological defect in the control of respiration, such as with bulbar poliomyelitis, degenerative neurological diseases, intracranial neoplasm, brain stem infarction, narcotic or sedative overdose, bilateral cervical cordotomy, Mixed apnea is diagnosed when elements of central control and obstruction are both found to be contributing to the apnea. It is generally classified with the predominating element. However, in many cases of advanced obstructive sleep apnea, a central element is notable

Sleep Disordered Breathing Primary snoring Primary snoring RDI < 5 RDI < 5 No daytime sleepiness No daytime sleepiness Upper airway resistance syndrome (UARS) Upper airway resistance syndrome (UARS) RDI < 5 RDI < 5 Arousal Index > 5 Arousal Index > 5 Obstructive sleep apnea syndrome (OSAS) Obstructive sleep apnea syndrome (OSAS) RDI > 5 RDI > 5 O 2 desaturation < 90% O 2 desaturation < 90% Obesity hypoventilation syndrome (Pickwickian) Obesity hypoventilation syndrome (Pickwickian) BMI >30 kg/m 2 BMI >30 kg/m 2 Daytime hypercapnia w/ PaCO 2 ≥ 45mmHg Daytime hypercapnia w/ PaCO 2 ≥ 45mmHg Sleep disordered breathing Sleep disordered breathing