Low cost, non-invasive, and continuous vital signs monitoring device for pregnant women in low resource settings (Lvital device)

Abstract

Around 800 women die each day from complications of pregnancy and childbirth in the world. Vital Signs monitoring (such as blood pressure, pulse rate, and temperature) are among fundamental parameters of ensuring the health and safety of women and newborns during pregnancy, labor, and childbirth. Approximately, 10% of women experience hypertension (greater than140/90) during pregnancy. High blood pressure during pregnancy can cause extra stress on the heart and kidneys and can increase the risk of heart disease. Therefore, early recognition of abnormal vital signs, which are induced due to pregnancy can allow for timely identification of clinical deterioration. Currently used technologies are expensive and complex design with implementation challenges in low-resource settings where maternal morbidity and mortality is higher. Thus, considering the above need, here a hardware device has been designed and developed, which is a low cost, and portable for pregnant women's vital signs (with cuff-less blood pressure, heart rate, and body temperature) monitoring device. The developed device would have a remarkable benefit of monitoring the maternal vital signs especially for those in low resource settings, where there is a high paucity of vital signs monitoring devices.

Keywords: 3D print; Blood Pressure; Cuffless; Pulse rate; Temperature; Vital signs.

Graphical abstract

Fig. 1

The general block diagram of the device.

Fig. 2

a) The main 3D designed box where the microcontroller and other circuit was placed, b) The cover lid, c) The final assembled 3D design.

Fig. 3

The general flow chart of the Arduino firmware (Arduino code).

Fig. 4

The 3D printed main box.

Fig. 5

Shows the connection of a) LCD, b) LEDs and buzzer with Arduino, and c) LCD and LEDs with coverlid.

Fig. 6

Integration of (a) blood pressure sensor, (b) pulse rate sensor, (c) temperature sensor, and (d) GSM with Arduino.

Fig. 7

The general wiring/schematic diagram of the hardware.

Fig. 8

LCD and LEDs mounting in the upper case. (a) the lid with LCD and LEDs space, (b) attaching the LCD with lid using glue. (c) mounting the LEDs on stripboard and lid, (d) front side of the lid after mounting LCD and LEDs.

Fig. 9

Shows steps to the pulse sensor SEN-11574 with the plastic enclosure. (a) clipper with the sensor, (b) putting the sensor inside the clipper, (c) attaching the sensor with glue inside the clipper, (d) attaching the plastic cover with glue.

Fig. 10

Mounting the solar panel on the hardware. (a) the solar panel with holder, (b) putting glue at the backside of the solar panel (c) attaching the panel on the top of the lid. (d) putting glue to attach the panel holder, (d) holder attached around the solar panel to strengthen the solar panel in its position.

Fig. 11

Steps to close the lower case with the upper case (lid). (a) backside of the lid, (b)mounting the backside of the lid to the lower case, (c) lid fixed to the lower case.

Fig. 12

The final concept proof developed prototype of the device.

Fig. 13

Operation and testing of the device. (a) shows ON the device, (b) measuring blood pressure, (c) measuring the continuous pulse rate and temperature.

Fig. 14

Percentage Error factor of blood pressure measurements.

Fig. 15

Percentage error factor of pulse rate and temperature measurement.

Fig. 16

Distribution of the average samples recorded by the Lvital device and the comparator device, of the respective parameter. a) Systolic blood pressure measurement, b) diastolic blood pressure measurement, c) Pulse rate measurement, d) Body temperature measurement.

Fig. 16

Distribution of the average samples recorded by the Lvital device and the comparator device, of the respective parameter. a) Systolic blood pressure measurement, b) diastolic blood pressure measurement, c) Pulse rate measurement, d) Body temperature measurement.

Fig. 17

The GSM Validation. (a) shows the front side of the prototype through which the USB is inserted and connected to the Arduino board to upload the developed Arduino script. (b) shows sample low temperature and pulse rate measurement without attaching the sensor to the human body (made testing purpose), (c) shows the GSM triggered to send SMS, (d) shows the SMS sent successfully to the caregiver phone number, (e) shows the content of the message received from the Lvital device.