Polysomnography Module

Overview

The Polysomnography module tracks comprehensive sleep study data for patients with sleep apnea. It consists of two distinct study types:

Basal Study

Initial diagnostic polysomnography to assess baseline sleep apnea severity

Titration Study

Pressure titration study to determine optimal CPAP/BiPAP settings

Both study types are linked to the patient’s active admission (ingreso) to ensure proper data organization across treatment cycles.

Basal Polysomnography

Model: `PolisomnografiaBasal`

The basal study establishes the patient’s baseline sleep apnea metrics before treatment begins. Location: apps/exams/models.py:184-224

Data Fields

fecha_basal

DateField

required

Date when the basal sleep study was conductedForm Label: “Fecha de Estudio Basal”

iah

DecimalField

required

Apnea-Hypopnea Index (AHI) - The number of apnea and hypopnea events per hour of sleep

Format: Decimal (5 digits, 2 decimal places)
Form Label: “Índice de Apneas (IAH)”
Clinical Significance: Primary diagnostic metric for sleep apnea severity

severidad_apnea

CharField

required

Clinical severity classification based on AHI scoreAvailable Choices:

NORMAL - Normal (no sleep apnea)
LEVE - Mild (AHI 5-15)
MODERADA - Moderate (AHI 15-30)
GRAVE - Severe (AHI > 30)

Form Label: “Severidad de Apneas”

ido

DecimalField

required

Oxygen Desaturation Index (ODI) - Average number of oxygen desaturation events per hour

Format: Decimal (5 digits, 2 decimal places)
Form Label: “IDO”
Clinical Significance: Measures oxygen deprivation during sleep

eficiencia

DecimalField

required

Sleep Efficiency - Percentage of time in bed actually spent sleeping

Format: Decimal (5 digits, 2 decimal places)
Form Label: “Eficiencia(%)”
Range: 0-100%

Relationships

ingreso

ForeignKey

Links to the patient’s active admission recordRelated Name: polisomnografias_basales

registrado_por

ForeignKey

User who registered this basal studyRelated Name: polisomnografias_basales_registradas

Registration Workflow

View: register_basal (apps/exams/views.py:217-242)

def register_basal(request, patient_id):
    patient = get_object_or_404(Patient, id=patient_id)
    ingreso_actual = patient.ingresos.filter(estado='ACTIVO').first()
    
    if request.method == 'POST':
        form = BasalForm(request.POST)
        if form.is_valid():
            basal = form.save(commit=False)
            basal.ingreso = ingreso_actual  # Link to active admission
            basal.registrado_por = request.user
            basal.save()
            return redirect('patient_clinical', patient_id=patient.id)

The basal IAH value is automatically used as a reference in the Monitoring module to calculate treatment correction percentage.

Titration Polysomnography

Model: `PolisomnografiaTitulacion`

The titration study determines the optimal pressure settings and mask configuration for PAP therapy. Location: apps/exams/models.py:228-289

Data Fields

fecha_titulacion

DateField

required

Date when the titration study was conductedForm Label: “Fecha de Estudio de Titulación”

tipo_titulacion

CharField

Type of positive airway pressure therapy titratedAvailable Choices:

CPAP - Continuous Positive Airway Pressure
BPAP - Bilevel Positive Airway Pressure
BPAP ST - BiPAP with Spontaneous/Timed backup rate

Form Label: “Tipo de Titulación”

presion_ipap

DecimalField

required

Inspiratory Positive Airway Pressure - Pressure delivered during inhalation

Format: Decimal (5 digits, 2 decimal places)
Unit: cmH₂O
Form Label: “Presión IPAP en Titulación”
Clinical Note: For CPAP mode, IPAP = EPAP (single pressure)

presion_epap

DecimalField

Expiratory Positive Airway Pressure - Pressure maintained during exhalation

Format: Decimal (5 digits, 2 decimal places)
Unit: cmH₂O
Form Label: “Presión EPAP en Titulación”
Optional: Only applicable for BiPAP modes

frecuencia_respiratoria

IntegerField

Respiratory Rate - Breaths per minute for BiPAP ST mode

Unit: Respirations per minute (rpm)
Form Label: “Frecuencia Respiratoria”
Optional: Only applicable for BiPAP ST mode
Help Text: “Respiraciones por minuto (rpm)“

Mask Configuration

tipo_mascara

CharField

required

Type of interface mask used during titrationAvailable Choices:

PILLOW NASAL - Nasal pillow (minimalist, inserted into nostrils)
NASAL - Nasal mask (covers nose only)
ORONASAL - Full face mask (covers nose and mouth)

Form Label: “Tipo Mascara” Default: “No especificado”

talla_mascara

CharField

required

Size of the mask fitted to the patientAvailable Choices:

SMALL - Small
MEDIUM - Medium
LARGE - Large

Form Label: “Talla Mascara” Default: “No especificado”

Relationships

ingreso

ForeignKey

Links to the patient’s active admission recordRelated Name: polisomnografias_titulaciones

registrado_por

ForeignKey

User who registered this titration studyRelated Name: polisomnografias_titulaciones_registradas

Registration Workflow

View: register_titulacion (apps/exams/views.py:247-272)

def register_titulacion(request, patient_id):
    patient = get_object_or_404(Patient, id=patient_id)
    ingreso_actual = patient.ingresos.filter(estado='ACTIVO').first()
    
    if request.method == 'POST':
        form = TitulacionForm(request.POST)
        if form.is_valid():
            titulacion = form.save(commit=False)
            titulacion.ingreso = ingreso_actual
            titulacion.registrado_por = request.user
            titulacion.save()
            return redirect('patient_clinical', patient_id=patient.id)

Clinical Workflow

Step 1: Basal Study (Diagnostic)

Purpose: Establish baseline sleep apnea severity

Conduct overnight polysomnography without treatment
Record AHI, ODI, and sleep efficiency
Classify severity (Normal/Mild/Moderate/Severe)
Determine if PAP therapy is indicated

Key Metric: AHI determines treatment eligibility and severity classification

Step 2: Titration Study (Treatment Planning)

Purpose: Determine optimal PAP settings and mask fit

Trial different pressure levels during sleep
Test various mask types and sizes for comfort
Record optimal IPAP/EPAP pressures
Document respiratory rate for BiPAP ST if needed

Output: Prescription for home PAP therapy with specific settings

Step 3: Equipment Assignment

After titration, the determined settings are used to:

Configure the patient’s home PAP device (see Medical Equipment)
Provide the appropriately sized mask
Begin ongoing monitoring (see Monitoring)

Data Retrieval

Accessing Polysomnography Data

View: patient_clinical (apps/exams/views.py:12-58)

# Get all basal studies for active admission
basales = PolisomnografiaBasal.objects.filter(
    ingreso=ingreso_actual
).order_by('-id')

# Get all titration studies for active admission
titulaciones = PolisomnografiaTitulacion.objects.filter(
    ingreso=ingreso_actual
).order_by('-id')

# Get most recent basal IAH for monitoring reference
psg = PolisomnografiaBasal.objects.filter(
    ingreso=ingreso_actual
).last()
valor_basal = psg.iah if psg else 0

All polysomnography data is filtered by the patient’s active admission (estado='ACTIVO') to ensure data isolation between treatment cycles.

Clinical Significance

Apnea-Hypopnea Index (AHI)

The AHI is the gold standard for diagnosing and classifying sleep apnea:

Severity	AHI Range	Clinical Significance
Normal	< 5	No sleep apnea
Mild	5-15	Minimal symptoms, lifestyle modifications may suffice
Moderate	15-30	Significant symptoms, PAP therapy recommended
Severe	> 30	High cardiovascular risk, immediate PAP therapy required

Oxygen Desaturation Index (ODI)

Measures how often blood oxygen drops ≥3% or ≥4% per hour:

Correlates with cardiovascular complications
Higher ODI indicates more severe oxygen deprivation
Used to assess treatment urgency

Sleep Efficiency

Percentage of time in bed actually spent sleeping:

Normal: 85-95%
Poor: < 85% (indicates sleep fragmentation)
Low efficiency suggests frequent awakenings from apnea events

The basal IAH value is automatically propagated to the Monitoring module at /exams/views.py:78-79, where it’s used to calculate treatment correction percentage.

Monitoring

Track treatment effectiveness using basal IAH as reference

Medical Equipment

Assign PAP devices using titration pressure settings

Pulmonology

Specialist consultations for complex cases

Get Started

Core Features

User Guides

Medical Modules

Polysomnography Module

Overview

Basal Study

Titration Study

Basal Polysomnography

Model: `PolisomnografiaBasal`

Data Fields

Relationships

Registration Workflow

Titration Polysomnography

Model: `PolisomnografiaTitulacion`

Data Fields

Mask Configuration

Relationships

Registration Workflow

Clinical Workflow

Data Retrieval

Accessing Polysomnography Data

Clinical Significance

Apnea-Hypopnea Index (AHI)

Oxygen Desaturation Index (ODI)

Sleep Efficiency

Monitoring

Medical Equipment

Pulmonology

Build docs developers (and LLMs) love

Get Started

Core Features

User Guides

Medical Modules

Documentation Index

​Overview

Basal Study

Titration Study

​Basal Polysomnography

​Model: PolisomnografiaBasal

​Data Fields

​Relationships

​Registration Workflow

​Titration Polysomnography

​Model: PolisomnografiaTitulacion

​Data Fields

​Mask Configuration

​Relationships

​Registration Workflow

​Clinical Workflow

​Data Retrieval

​Accessing Polysomnography Data

​Clinical Significance

​Apnea-Hypopnea Index (AHI)

​Oxygen Desaturation Index (ODI)

​Sleep Efficiency

​Related Modules

Monitoring

Medical Equipment

Pulmonology

Build docs developers (and LLMs) love

Overview

Basal Polysomnography

Model: `PolisomnografiaBasal`

Data Fields

Relationships

Registration Workflow

Titration Polysomnography

Model: `PolisomnografiaTitulacion`

Data Fields

Mask Configuration

Relationships

Registration Workflow

Clinical Workflow

Data Retrieval

Accessing Polysomnography Data

Clinical Significance

Apnea-Hypopnea Index (AHI)

Oxygen Desaturation Index (ODI)

Sleep Efficiency

Related Modules