We are working to optimize the abdominal strap for the Neonatal Temperature Monitor and IncuBaby devices. Both of these devices monitor neonatal temperature through a temperature probe that reads skin temperature just above the liver:

The placement of the temperature probe is essential. The skin temperature above the liver radiates heat that is close to core body temperature. This is an accurate and noninvasive method of measuring core body temperature.

An abdominal strap holds the temperature probe in place. There are five main criteria for the design of the strap.

 

 

The NTM’s abdominal strap should be:

• Comfortable for neonates
• Easy to use/attach
• Easy to clean and resuse
• Adjustable to different sizes (~17-35cm)
• Able to ensure correct placement of probe

**Most importantly: Why do we want to monitor newborn temperature? Neonatal hypothermia is the leading cause of neonatal mortality in the developing world. It is also easily preventable. Hospitals are often overcrowded and understaffed, and without a consistent way to monitor temperature, neonatal hypothermia frequently goes unidentified. The NTM allows for a way to continuously monitor temperature and alert nurses and hospital staff of fever or hypothermia. Knowledge of the problem can empower individuals to take simple steps toward preventing hypothermia and reducing neonatal mortality.**

Note: for more information on neonatal hypothermia stay tuned for a future post coming soon!

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Below is the strap design currently in use. This strap features a shoulder strap addition that holds the abdominal belt in place.

Sewn in snaps attach the probe to the belt. The belt is fastened with a plastic buckle and held in place via the shoulder strap. As we seek to improve this design, we aim to do the following:

1. Improve/simplify fastening mechanism.
2. Eliminate shoulder strap and find alternate no-slip mechanism.
3. Minimize probe encasement while ensuring placement.

Below are some of the initial designs we considered, brainstorming with different ways to approach these design goals.

Moving forward we have experimented with incorporating:

• Magnetic clipping device to fasten the belt (simplify method)
• Baby-safe silicone padding to prevent belt from slipping (instead of shoulder strap)
• 3D-printed snap mechanism for temperature probe (prevent movement of probe)

Additionally, we noticed that of existing neonatal belts, the majority have a much larger surface area and height around the baby. Umbilical hernia belts, though reaching a slightly lower abdominal area of the baby, have an average height of 5 in. Moving forward, we want to consider belt height as a factor for experimentation.

Here is the first prototype with the changes mentioned above. The temperature probe snaps directly into the belt that contains a 3D-printed encasement. The probe also contains a magnet. Only when the probe is in place can the belt be successfully fastened with the external magnetic clip and the magnet on the probe. An adjustable silicone back-pad is placed around the belt as the no-slip mechanism. The back-pad uses the body weight of the baby as well as tension from the silicone surface to hold the belt in place. The silicone used is similar to silicone used in pacifiers and therefore safe and gentle for newborns.

This strap is simple to use, gentle for the neonates, easy to clean, and holds the temperature probe in place. To improve this prototype, we are going to address the protrusion of the 3D-printed snap and assess ways to improve the strength of the magnetic clip.

Within the coming weeks, we will continue to iterate on this prototype and begin testing. Stay tuned for more posts and updates on the design process here at Rice 360°!