Detecting Sleep Apnea with the TI MSP430 Microcontroller Aaron Sander & Ramzie Fathy Mentor: Sakib Hasan CURENT YSP Final Presentation Tuesday July 16 th, 2014 Knoxville, Tennessee

Our Objective Sleep Apnea is very common in young infants who have an underdeveloped nervous system. Our research was based around finding a system which could analyze breathing signals in various situations and alert caretakers if apnea sets in. 2

OUTLINE {slide #} What is Sleep Apnea? What is a Microcontroller? TI MSP430 Results

What is Sleep Apnea? Apnea literally means “cessation of breathing” Definition is a lack of breathing for as low as 20 seconds up to 2 minutes for adults, may happen nearly 100 times a night Three majors forms of Sleep Apnea Obstructive Sleep Apnea (most common) - when airway is physically blocked by tongue, tonsils, etc. Central Sleep Apnea (20% of cases) - when brain forgets to tell body to breathe, especially common in infants with undeveloped nervous system Mixed Sleep Apnea - combination of the two 4

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Central Sleep Apnea Breathing regulated by Pre-Bötzinger Complex which may not be developed yet in young children Can be common in people who have Parkinson’s, Alzheimer’s, or have had a stroke or brain injury Located in Medulla Oblongata (brainstem) Oxygen level in body can drop to life-threatening levels (hypoxemia) Inversely, the CO2 levels in the blood can increase to an unsafe level (hypercapnia) 6

Apnea – Hyperventilation - Apnea 7 Cheynes-Stokes Respiration

The Microcontroller The Microcontroller is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Programmed in different programming languages Capabilities include pH sensor, temperature indicator Many Applications 8

MSP430 A mixed-signal microcontroller family from Texas Instruments. Capabilities include temperature indicator, Red/Green LEDs, and Micro- USB port. Programmed in C. 9

Results Created a program using the MSP430 Written in C on Code Composer Studio Piezoelectric Transducer is used to convert pressure (breath) to electrical signal Program analyzes this to determine if a child is properly breathing Threshold can be modified on case by case basis 10

Actual Code 11

Pseudo-Code Clock On Timer On Green LED On Analog-Digital Converter On Threshold determined If (voltage >= threshold) Timer resets to 0 If (voltage < threshold) Clock continues counting Loop When clock count = 10, Red LED will indicate apnea 12

Testing the Program 13

References MSP430 User Guides and Datasheets Rybak IA, Abdala AP, Markin SN, Paton JF, Smith JC (2007). "Spatial organization and state-dependent mechanisms for respiratory rhythm and pattern generation". Progress in Brain Research. Progress in Brain Research 165: 201–20"Spatial organization and state-dependent mechanisms for respiratory rhythm and pattern generation" 14

Acknowledgements 15 Sakib Hasan CURENT Program National Science Foundation