2.2 Clinical History, Screening Tools & Physical Assessment

2.2 Clinical History, Screening Tools & Physical Assessment

Accurate polysomnographic evaluation relies heavily upon correlating overnight physiological recordings with a thorough pre-study clinical assessment. As a Certified Polysomnographic Technician (CPSGT), obtaining a structured medical and sleep history, administering validated screening tools, and performing targeted physical airway examinations allows you to anticipate clinical challenges, recognize patient-specific risks, and optimize recording montages.

---

1. Clinical Sleep History & Cardinal Chief Complaints

During pre-study intake, the sleep technologist evaluates the patient's chief complaints, sleep patterns, and medical history. The major presenting symptoms in sleep medicine include:

+-----------------------------------------------------------------------------+
|                        CARDINAL SLEEP CHIEF COMPLAINTS                      |
|                                                                             |
|   1. Excessive Daytime Sleepiness (EDS) ---> Involuntary dozing, sleepiness |
|   2. Nocturnal Breathing Symptoms      ---> Snoring, choking, gasping       |
|   3. Sleep Fragmentation & Insomnia    ---> Frequent awakenings, nocturia   |
|   4. Morning Neurological Symptoms     ---> Frontal headaches, brain fog    |
|   5. Motor & Behavioral Phenomena      ---> Restless legs, kicking, thrashing|
+-----------------------------------------------------------------------------+

Clinical Symptom Profiles:

• Excessive Daytime Sleepiness (EDS): The inability to maintain wakefulness and alertness during major daytime waking episodes, resulting in unintended sleep episodes or sleepiness. It must be differentiated from fatigue or asthenia (lack of physical energy vs. propensity to fall asleep).
• Habitual Snoring & Choking Awakenings: Vibratory upper airway tissue sound during inspiration. Resuscitative snorts or abrupt gasping awakenings indicate transient airway occlusion and arousal.
• Nocturia: Waking multiple times per night to urinate. In OSA, repetitive negative intrathoracic pressure swings cause right atrial stretching, triggering the release of Atrial Natriuretic Peptide (ANP), which induces nocturnal hyperuresis.
• Morning Headaches: Characteristically bifrontal or diffuse dull aching upon waking, resulting from nocturnal hypercapnia ($CO_2$ retention) causing cerebral vasodilation.
• Non-Restorative Sleep & Mood Disturbances: Feeling unrefreshed despite seemingly adequate time in bed, often accompanied by irritability, cognitive decline, or depression.

---

2. Validated Sleep Screening Questionnaires

Standardized screening questionnaires provide quantifiable, reproducible measurements of sleepiness and sleep apnea risk.

+-----------------------------------------------------------------------------+
|                     EPWORTH SLEEPINESS SCALE (ESS) MATRIX                   |
|                                                                             |
|   Scale: 0 = Would never doze | 1 = Slight chance | 2 = Moderate | 3 = High |
|                                                                             |
|   SITUATION                                                     SCORE (0-3) |
|   1. Sitting and reading .....................................     [   ]    |
|   2. Watching TV .............................................     [   ]    |
|   3. Sitting, inactive in a public place (e.g., a theater) ...     [   ]    |
|   4. As a passenger in a car for an hour without a break .....     [   ]    |
|   5. Lying down to rest in the afternoon when circumstances    |            |
|      permit ..................................................     [   ]    |
|   6. Sitting and talking to someone ..........................     [   ]    |
|   7. Sitting quietly after a lunch without alcohol ...........     [   ]    |
|   8. In a car, while stopped for a few minutes in traffic ....     [   ]    |
|                                                                             |
|   TOTAL SCORE (Sum of 8 items, Range 0 - 24): ................     [   ]    |
|   - Score 0 to 10: Normal daytime sleepiness                                |
|   - Score 11 to 15: Moderate excessive daytime sleepiness                   |
|   - Score 16 to 24: Severe excessive daytime sleepiness                     |
+-----------------------------------------------------------------------------+

The STOP-BANG Screening Tool for OSA:

The STOP-BANG questionnaire is a widely validated, 8-item dichotomous (Yes/No) questionnaire used to screen for Obstructive Sleep Apnea risk in surgical, clinical, and sleep center populations.

STOP-BANG Risk Stratification:
- Low Risk:       0 to 2 affirmative answers (Score 0-2)
- Intermediate:   3 to 4 affirmative answers (Score 3-4)
- High Risk:      5 to 8 affirmative answers (Score 5-8)
                  -- OR --
                  >= 2 STOP criteria (S, T, O, P) PLUS:
                  - Male gender, OR
                  - BMI > 35 kg/m2, OR
                  - Neck circumference > 17 in (male) / > 16 in (female)

The Berlin Questionnaire:

Divides 10 questions into three specific categories:

1. Category 1: Snoring severity, frequency, and witnessed apneas (High risk if $\ge 2$ positive responses).
2. Category 2: Daytime sleepiness, fatigue, and drowsy driving (High risk if $\ge 2$ positive responses).
3. Category 3: History of hypertension or $\text{BMI} > 30\text{ kg/m}^2$ (High risk if positive for hypertension OR $\text{BMI} > 30$).

• Overall Scoring: A patient is classified as High Risk for OSA if they score positive in 2 or more categories.

---

3. Physical Airway Assessment & Anatomical Classifications

Upper airway collapsibility is heavily influenced by craniofacial morphology and soft tissue crowding within the pharyngeal space.

+-----------------------------------------------------------------------------+
|                        MALLAMPATI AIRWAY CLASSIFICATION                     |
|    (Assessed with patient seated upright, mouth wide open, tongue extended   |
|     WITHOUT phonation / phonating alters soft palate position)              |
|                                                                             |
|   [CLASS I]               [CLASS II]             [CLASS III]     [CLASS IV] |
|   Full visualization      Soft palate, uvula     Soft palate     Hard palate|
|   of soft palate, uvula,  and fauces visible;    and base of     only       |
|   fauces, and pillars.    pillars obscured.      uvula visible.  visible.   |
|                                                                             |
|   +------------------+    +----------------+     +------------+  +---------+|
|   |    ( O  O )      |    |   ( O  O )     |     |  ( O  O )  |  | ( O  O )||
|   |     |    |       |    |    |    |      |     |   |    |   |  |  |    | ||
|   |    /      \      |    |   /      \     |     |  /      \  |  | /      \||
|   |   | [Uvula]|     |    |  | [Uvula]|    |     | |[Palate] |  | |[Hard]  ||
|   |   |Pillars |     |    |  |________|    |     | |_________|  | |________||
|   +------------------+    +----------------+     +------------+  +---------+|
|   Low Airway Risk         Mild Crowding          Moderate Risk   Severe Risk|
+-----------------------------------------------------------------------------+

Mallampati vs. Friedman Tongue Position (FTP):

• Mallampati Score: Evaluates visualization of the tonsillar pillars, soft palate, and uvula with the tongue actively protruded.
  • Class I: Soft palate, tonsillar pillars, and entire uvula completely visible.
  • Class II: Soft palate and uvula visible; tonsillar pillars partially obscured.
  • Class III: Soft palate and base of the uvula visible; tip of uvula obscured.
  • Class IV: Hard palate only visible; soft palate entirely obscured by the tongue base.
• Friedman Tongue Position (FTP): Evaluated with the tongue resting in a neutral, natural position inside the mouth without protrusion (which better reflects airway anatomy during sleep).
  • FTP Class I: Full visualization of uvula and tonsils.
  • FTP Class II: Uvula visible, but tonsillar pillars obscured.
  • FTP Class III: Soft palate visible; uvula obscured.
  • FTP Class IV: Hard palate only visible.

Tonsillar Hypertrophy Grading Scale:

• Grade 0: Tonsils surgically removed / absent.
• Grade 1: Tonsils confined within the tonsillar pillars (occupy $<25%$ of oropharyngeal width).
• Grade 2: Tonsils extend beyond pillars, occupying $25\text{--}50%$ of airway width.
• Grade 3: Tonsils occupy $50\text{--}75%$ of airway width.
• Grade 4 ("Kissing Tonsils"): Tonsils occupy $>75%$ of airway width and touch each other in the midline. Frequent primary cause of pediatric OSA.

Craniofacial Features Indicating OSA Risk:

• Retrognathia / Micrognathia: Recessed or abnormally small mandible, displacing the tongue base posteriorly toward the posterior pharyngeal wall.
• High-Arched / Gothic Palate: Narrow maxillary arch, reducing nasal cavity volume and increasing nasal airway resistance.
• Macroglossia: Abnormally large tongue (often seen in Down syndrome, acromegaly, or hypothyroidism).

---

4. Biometric Measurements & Vital Signs

During intake, the technician must accurately record baseline biometrics:

1. Neck Circumference:

   • Measured at the level of the cricothyroid membrane (just below the laryngeal prominence / Adam's apple).
   • Thresholds for elevated OSA risk: $>17\text{ inches (43.2 cm)}$ for men, $>16\text{ inches (40.6 cm)}$ for women.

2. Body Mass Index (BMI):

   • Calculated as: $\text{BMI} = \frac{\text{Weight (kg)}}{[\text{Height (m)}]^2} = \frac{\text{Weight (lbs)} \times 703}{[\text{Height (inches)}]^2}$
   • Classifications: Normal ($18.5\text{--}24.9$), Overweight ($25.0\text{--}29.9$), Class I Obesity ($30.0\text{--}34.9$), Class II Obesity ($35.0\text{--}39.9$), Class III / Morbid Obesity ($\ge 40.0\text{ kg/m}^2$).

3. Baseline Vital Signs:

   • Blood Pressure (BP), Pulse Rate, Respiratory Rate, and room-air Oxygen Saturation ($SpO_2$) must be recorded prior to lights out.
   • Alert Thresholds: Systolic $\text{BP} > 180\text{ mmHg}$, Diastolic $\text{BP} > 110\text{ mmHg}$, resting pulse $>100\text{ bpm}$ or $<45\text{ bpm}$, or baseline awake $SpO_2 < 90%$ on room air require clinical evaluation and possible medical director notification before proceeding.

4. Pre-Study Sleep Logs / Diaries:

   • 1 to 2 weeks of daily sleep diary tracking bedtime, wake time, daytime naps, caffeine, and alcohol consumption verify baseline sleep stability and rule out acute circadian misalignment prior to PSG and MSLT.