The management of patients hospitalised with diabetes mellitus is neglected in South Africa. The research on which this thesis is based assessed factors contributing to glycaemic control as well as evaluated an intervention aimed at improving of such control in diabetic inpatients. A survey of doctors and nurses measuring their perceptions, knowledge and attitudes regarding care of diabetic inpatients was done. This indicated a need for special training in inpatient diabetes care, where 90.5% of respondents realised that diabetes is a serious condition and 92.2% valued the importance of tight glycaemic control. Despite these perceptions, the knowledge of doctors and nurses caring for diabetic inpatients was suboptimal. A before and after study regarding an intervention to improve glycaemic control of diabetic inpatients consisted of a training programme and the introduction of an inpatient management protocol. The mean blood glucose on day one of admission after the intervention was significantly higher than before the intervention (p < 0.001). A significant improvement in mean blood glucose from day 1 to day 7 of hospitalisation was seen after the intervention (p < 0.001), which was not significant before (p = 0.33). The proportion of patients achieving glycaemic control did not significantly differ before and after the intervention (43.0% versus 43.7%, p = 0.97). A double blind randomised controlled trial to assess superiority of Ringer’s lactate solution compared to 0.9% Sodium chloride solution in the normalisation of pH in patients with diabetic ketoacidosis was done. The outcome of this study indicated that the time to normalisation of venous pH (pH > 7.32) (HR: 1.863, CI: 0.937 to 3.705, p = 0.758) was not significantly different between the two resuscitation fluid groups The time to reach a blood glucose of 14 mmol/L was significantly longer in the Ringer’s lactate group (p = 0.044) and patients needed significantly more insulin (p = 0.02). The overall conclusion of this study is that there is no significant benefit in using Ringer’s lactate solution as initial resuscitation fluid compared to the currently advised 0.9% Sodium chloride solution. / Thesis (PhD)--University of Pretoria, 2012. / Internal Medicine / unrestricted