Domain experts today agree that healthcare interoperability is highly valuable. However, questions arise on how to best achieve interoperability in both developed and developing nations, because only a few researchers look into the developing nations' situation. There are key differences in the challenges faced by developing countries when compared with developed countries where interoperability solutions emanate. These differences should inform the strategies used to achieve interoperability in these countries. Existing solutions for Health Information Exchange (HIE) rely on the availability of resources such as the internet. This research aims to enable the exchange of patient's information between hospitals in a developing African country without relying on the availability of internet connection. With a spotlight on low resource settings, this research develops an adaptable and scalable model that makes use of the Short Message Service (SMS) service as the exchange media in combination with the use of HL7 version 2.X message encoding. The effectiveness of the proposed model was evaluated by creating a typical exchange situation between two communicating hospitals. The outcome of the performance evaluation of the model was impressive with a successful delivery of most of the exchanged messages, an accurate interpretation of all delivered messages, and an average message transfer time of about 6 minutes. This model may serve as a solution-set for effective exchange of Patients' health information to fit the uniqueness of the developing African country scenario - where access to internet is limited and uneven spread.