This randomized controlled trial is designed to evaluate the effect of ERAS
protocol-based preoperative nutrition education and fasting management on postoperative
hydration status and nausea-vomiting outcomes in patients undergoing elective total knee
arthroplasty.
Total knee arthroplasty is an effective and frequently performed surgical intervention,
particularly among older adults with degenerative joint disease. However, perioperative
stress, prolonged fasting, and anesthesia-related factors may adversely affect
postoperative recovery, leading to dehydration, nausea, and vomiting. Optimizing
perioperative care through evidence-based ERAS protocols is therefore essential to
improve patient outcomes.
ERAS protocols promote a multidisciplinary approach aimed at reducing surgical stress and
accelerating postoperative recovery. One of the core components of ERAS is the
optimization of preoperative nutrition and hydration. According to evidence-based
guidelines, solid foods may be consumed up to 6 hours and clear liquids up to 2 hours
prior to elective surgery. This approach reduces unnecessary prolonged fasting, prevents
dehydration and insulin resistance, and improves postoperative comfort without increasing
anesthesia-related risks.
The study will be conducted in the orthopedic clinic of Acıbadem Altunizade Hospital.
Eligible patients scheduled for elective total knee arthroplasty will be recruited and
randomly assigned to either the intervention or control group using a simple
randomization method. Written informed consent will be obtained from all participants
prior to enrollment.
Patients in the intervention group will receive an ERAS-based preoperative nutrition
education leaflet and will be instructed to follow the standardized nutrition and fasting
protocol during the 24-hour preoperative period. Patients in the control group will
receive routine standard preoperative care as applied in the clinic.
Data collection will include demographic and clinical characteristics, postoperative
hydration status, nausea and vomiting frequency and severity, and fluid intake-output
monitoring. The following validated instruments will be used: the Surgical Thirst
Discomfort Scale, the Rhodes Index of Nausea, Vomiting and Retching, a numeric nausea
rating scale, and fluid balance monitoring forms.
Postoperative outcomes will be assessed for both groups, including hydration status,
nausea and vomiting incidence, and fluid intake-output balance. Statistical analyses will
be performed using SPSS software. Appropriate parametric or non-parametric tests will be
applied based on data distribution, with a significance level set at p < 0.05.
This study aims to provide evidence on the effectiveness of ERAS-based preoperative
nutrition education and fasting protocols in improving postoperative hydration and
reducing nausea and vomiting, thereby supporting the development of structured,
evidence-based nursing interventions in perioperative care.
