Study design
This study was a randomized controlled clinical trial. This study protocol was approved by the Ethics Committee of West China Hospital of Sichuan University (Chengdu, China). Written informed consents were obtained from the patients and their families. This study was registered under chictr.org, identifier number ChiCTR-IOQ-17011742.
Participants
In this study, we recruited 101 lumbar disc herniation patients undergoing PEID from August to November in 2017, in the Department of Orthopedics, West China Hospital of Sichuan University, a tertiary-level teaching hospital in southwest China. They were randomly divided into two groups. During perioperative period in the research, there were 51 patients who experienced multidisciplinary nutrition management in intervention group and 50 patients who experienced traditional nutrition management in control group. The inclusion criteria were: lumbar disc herniation patients undergoing PEID, patients who could experience the whole nutrition management according to the plan. The exclusion criteria were: patients who couldn’t eat orally, such as oral diseases, dysphagia and esophageal stenosis, patients who couldn’t tolerate our own nutritional product.
Interventions
The intervention protocols of the control group were traditional nutrition management during perioperative period. They were as follows: preoperative assessment without nutrition assessment, normal meal until up to 8–12 hours before the surgery and normal drinking until up to 4 hours before the surgery, oral feeding started gradually 4–6 hours after awaking from surgical anesthesia if there was not any discomfort.
The intervention protocols of the intervention group were multidisciplinary nutrition management during perioperative period. They were as follows: ①We built the multidisciplinary team including Spine Surgery, Nutrition Department, Department of Anesthesiology and Operating Room and determine everyone’s duties. Clinical dietitian formulated nutrition interventions for malnourished patients and developed four kinds of nutritional products (Table 1) for all the patients in intervention group. And they also solved problems about feeding nutritional products. ②We trained our team staff to promote the cooperation. Especially for ward nurse, operating room nurse and anesthesiologist, they knew the time of patients’ oral feeding and surgery very well. So that operation could be conducted successfully according to the plan. ③We implemented specific nutrition management interventions (Table 2).
The same interventions were applied in both groups: no routine bowel preparation, no routine use of gastric tube, urinary catheter and drainage tube, avoiding intraoperative hypothermia, postoperative glycaemic control and early and scheduled mobilization.
Discharge criteria including the following: normal vital signs, recovery of bowel function, adequate oral feeding and mobilization, good pain control and tolerance, and acceptance of discharge by patients. Patients were followed up by outpatient guidance or telephone within 1month after discharge. Patients in different groups were arranged in different wards in order to minimize protocol contamination.
Outcome Measures
The primary outcomes were gastrointestinal subjective feelings and satisfaction about nutrition management. Gastrointestinal subjective feelings included preoperative and postoperative hunger, thirst, nausea and vomiting degree. These feelings were assessed by numerical rating scale from 0 to 10. 0 meant that patients didn’t have this feeling and 10 meant the feeling was so strong that patients couldn’t tolerate. Satisfaction about nutrition management was from 0 to 100 including five kinds of satisfaction, taste, price, preoperative and postoperative hungry and thirsty degree, nurse’s care for nutrition requirement and nurse’s nutrition education.
Secondary outcomes were fasting time and postoperative recovery. Fasting time included preoperative solid and liquid fasting time and postoperative solid and liquid fasting time. From Guidelines [35], preoperative fasting time is defined as a prescribed period of time before the surgery when patients aren’t allowed the oral intake of solids or liquids and postoperative fasting time is defined as the same period of time after the surgery. Postoperative recovery included first urination, first out-of-bed activity, first passage of flatus and lumbar function recovery assessed by Oswestry disability index (ODI).
We collected patients’ baseline demographics and the ODI scores before surgery, fasting time, subjective feelings, postoperative recovery and the ODI scores on the 2nd day after surgery and the ODI scores on the 30th day after surgery.
Sample Size And Randomization
Sample size was calculated by pre-test outcome and sample size estimation formula. In pre-test, the scores of nutrition management satisfaction in all patients, control group and intervention group were respectively (87.10 ± 6.758), (84.80 ± 7.068) and (89.40 ± 5.892). The formula was as follow:
n1 = n2=2[(Zα/2 + Zβ)σ/δ]2, α = 0.05, β = 0.1, σ = S = 6.758, δ = 89.40–84.80 = 4.60. And considering the loss of visit, we calculated the number of required patients in each group was about 45–54.
Patients we recruited were randomly divided into two groups by using random number table generated by computer. The group information was preserved in a sealed envelope by a research assistant. When a patient who met inclusion and exclusion criteria was admitted, he or she would be divided into control group or intervention group by the group information.
Statistical Analyses
We input data using Microsoft Excel and used SPSS 20.0 for statistical analysis. We used mean ± SD to express numerical variables and frequency or percentage to express categoric variables. Differences between two groups were tested by t test for normally distributed data and rank test for non-normally distributed data. Compare in discrete variables were tested by Chi-square test and Fisher’s exact test. A value of p༜0.05 was considered statistically significant.