Smartphone-based low cost oximeter photoplethysmography

The pulse oximeter plethysmograph waveform reflects dynamic net changes in arteriolar inflow and venous outflow of tissue bed capillaries interrogated by the oximeter light emitting diodes. In this study we have developed a simple and low cost oximeter photoplethysmograph device which has been interfaced with mobile phone through USB (Universal Serial Bus). There has been an unprecedented increase in the number of mobile phone subscribers in the developing world which has seen mobile phones used in ways not seen in the developed world. Mobile phones can be used to display the patient´s blood oxygen saturation and pulse rate, thus dramatically reducing the cost, and to provide doctors stationed on site a means of diagnosis before the need for any medical evaluation.