Preoperative Administration of Oral Carbohydrate Drink and Postoperative Insulin Resistance
Condition: Insulin Resistance; Inflammatory Response; Exaggerated Well-Being; Length of Stay
MeSH terms: Insulin Resistance
Study type: Interventional

Summary: 
      This study compared traditional concept of preoperative fasting before elective open colon
      surgery and preoperative treatment with carbohydrate oral drink in intention to improve
      postoperative stress response to surgical procedure. Hypothesis was: preoperative oral
      carbohydrate drink reduces postoperative insulin resistance, improves insulin sensitivity,
      reduces postoperative inflammatory response in terms of the value of Glasgow Prognostic Score
      (GPS) and IL-6, improves postoperative patient's subjective well-being and surgical clinical
      outcome.
    

Detailed description: 
      This prospective randomized, controlled clinical study was carried out in the Department of
      Anesthesiology and Intensive Care Unit and Department of Surgery at the Cantonal Hospital
      Zenica, Bosnia and Herzegovina. After obtaining ethical committee approval 50 participants,
      scheduled for elective open colon surgery were included into study. Sample size was estimated
      using sample size calculator software and power analysis with 95% confidence interval and
      power of 80%. Statistical significance was considered as p< 0,05. The calculation indicated
      19 participants per group would be sufficient to detect a 50% difference for insulin
      resistance between the groups. Assuming dropout would lead to a total sample size of 50
      participants. Before each participant agreed to the join the study, the purpose and
      procedures of the study were fully explained and informed and written consent was obtained
      from each participant. A preoperative anesthetic examination was conducted the day before
      surgery. The participants who fulfilled study criteria were randomly allocated into two
      groups of 25 participants, depending on the preoperative treatment. The intervention group,
      received preoperative carbohydrate oral supplementation (CHO group) and the control group
      (FAST group) underwent to a conventional routine of preoperative fasting. Randomization was
      performed by computer generated randomization codes. The codes which indicated the treatment
      were held in sealed opaque envelopes. Nurse who conducted randomization and opened the
      envelopes the night before surgery was blinded to the study protocol as well as the surgeons,
      nurses, anesthesiologists and staff involved in data collection.

      The participants of FAST group were undergone to the traditional concept of preoperative
      fasting before surgical procedure. The participants in the intervention group received
      carbohydrate oral supplement at 10:00 pm the evening before surgery and again on the day of
      surgery, 2 hours before induction of anesthesia. Assessment of clinical parameters started at
      06:00 am on the day of surgery (basal value). The fasting peripheral venous blood samples
      were collected to measure serum levels of glucose, insulin, C-reactive protein, albumin and
      IL-6, and further 6 hours post-surgery, at 06.00 am on the first postoperative day and at
      06:00 am on the second postoperative day. All patients underwent general anesthesia followed
      by colon surgery. Assessment of subjective well-being was performed immediately before
      induction into anesthesia using a 10 cm horizontal Visual Analogue Scales and then repeated
      for 0-4, 4-8, 8-12 and 12-24 hours post-surgery. Pain at rest, pain with mobilization,
      thirst, hunger, mouth dryness, anxiety and weakness were evaluated. The patients were
      explained how to use the scale. Surgical outcome was evaluated by postoperative return of
      gastrointestinal function, time to independent ambulation and postoperative discharge day.
      Postoperative data included and the time to oral intake. The following data were recorded
      also: age, sex, body weight, body mass index, American Society of Anesthesiologists (ASA)
      physical status class, nutritional status of the participants according to Nutritional Risk
      Screening 2002 (NRS-2002), tumor localization, type of surgery, duration of surgery,
      preoperative fasting time and, blood loss during surgery
    

Intervention name(s): preoperative nutrition
Intervention type(s): Dietary Supplement
Intervention description(s): The participants of experimental group received 400 mil of a clear carbohydrate drink (12,5 gr/100 mil carbohydrate, 50 kcal/100ml, pH 5.0) at 10:00 pm the evening before surgery and another 200 mil of the carbohydrate drink on the day of surgery, 2 hours before induction of anesthesia. After surgery the participants fasted until the recovery of function of the bowel.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: The diagnostic protocol for colon cancer was performed in patients at the surgery department. The patients with diagnosed colon tumor were prepared for the surgical procedure. After that, patients were examined to a preoperative anesthetic visit. During the visit, participants were assessed according to eligibility for enrollment in the study. The participants who have met the eligibility criteria have explained the nature of the study protocol. Those who agreed to participate in the study were randomized to one of two study groups for the duration of the study.
Masking: Triple (Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: fasting; carbohydrate; insulin resistance