From Orlando Hoilett of Calvary Engineering on Hackaday.io:

Biomed Shield for Arduino 101

A sweet Arduino shield with a ton of cool sensors for physiological parameters such as heart rate and breathing rate

The features include:

• Heart Rate Monitoring with the MAX30101
• Pulse Oximeter with the MAX30101
• Electrocardiogram, Electromyogram, and Electrooculogram with our Super Simple EXG Circuit
• Bioimpedance with the AD5934
• Body Temperature with the MLX90614
• Ambient Light with a CdS Photocell
• Ambient Temperature with a Thermistor

https://github.com/CalvEngIO/BiomedShield

https://github.com/CalvEngIO/BiomedShield

https://github.com/CalvEngIO/BiomedShield

The design files and source code are available on GitHub:

CalvEngIO/BiomedShield