1. Department of Surgery, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg 2193, South Africa
2. Nursing Department, Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg 2193, South Africa
3. Department of Dietetics, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg 2193, South Africa
4. Department of Cardiothoracic Surgery, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg 2000, South Africa