The purpose of this study is to gather measurement data for the development and testing of a wearable patient monitor's pulse oximeter. The PaMo patient monitor measures respiratory rate, blood oxygen saturation, and electrocardiogram (ECG). The device transmits data via Bluetooth to a mobile application for immediate interpretation. The device, developed at Tampere University, aims to provide a wireless solution for monitoring patients' breathing and circulation, especially after surgical procedures. The collected data will be used to demonstrate the device's oxygen saturation measurement capability according to the European ISO 80601-2-61:2019 standard, contributing to further refinement of the solution.

The study involves controlled desaturation for voluntary participants, gradually lowering blood oxygen levels by reducing the inhaled air's oxygen content. This reduction is facilitated by the Hypoxico device, simulating high-altitude conditions. The device, connected to a transparent tent placed over subject's upper body, gradually decreases the surrounding air's oxygen content. Oxygen saturation is lowered to a minimum of 70%, and the measurement period lasts a maximum of 30 minutes. A physician and two research team members will be present throughout the measurement. Vital signs, including respiratory rate, heart's electrical activity, blood pressure, and oxygen saturation, will be monitored using the patient monitor in addition to the device being studied. Carbon dioxide levels in exhaled breath will be measured using nasal cannulas.

Reference devices:

Masimo RAD-97 pulse oximeter is a class IIB device and leading technology in measuring SpO2 and has demonstrated high sensitivity and accuracy even during conditions of motion and low perfusion. SpO2 and pulse will be monitored during the measurement period.

GE Carescape B450 is a class IIB device and globally used patient monitor with highly sophisticated algorithms for arrhythmia, non-invasive blood pressure and SpO2. 5-digit ECG, non-invasive blood pressure, IP, SpO2 and pulse will be monitored during the measurement period.

The study does not include a control group. All subjects are using the devices in similar way and the parameters collected from the same individual using two different methods are compared.

Inclusion Criteria:

• Age: minimum of 18 years and max 40 years
• ASA category 1
• positive Allen's test
• Passing the physical examination
• Ability to give informed consent
• Volunteering to the study

Exclusion Criteria:

• Age under 18 or over 40 years
• Smoker
• Pregnancy
• Does not pass the physical examination
• Negative Allen's test
• Relevant medical illnesses
• Cardiovascular disease
• Pulmonary disease
• Insufficient knowledge in Finnish or English
• Cardiac pacemaker
• Inability to give informed consent
• Denial