Postoperative Complications
Conditions
Keywords
Colorectal Surgery, Bioelectrical Impedance Analysis, Phase Angle, Extracellular Water, Intracellular Water, Body Composition, Preoperative Hydration, Balanced Isotonic Crystalloid, Perioperative Fluid Therapy, Clavien-Dindo Classification
Brief summary
This single-center study will evaluate whether short-term changes in bioelectrical impedance measurements after a standardized preoperative intravenous fluid infusion can help predict complications following elective colon or rectal surgery. The prospective group will include 120 consecutive adults. After emptying the bladder, participants will be weighed and assessed barefoot on a standing multifrequency bioelectrical impedance device. They will then receive Ionolyte, a balanced isotonic crystalloid, at 15 mL/kg based on the lower of actual and ideal body weight, up to 1,000 mL, over exactly 40 minutes. Participants will empty the bladder again and undergo repeat measurement 60 minutes after infusion start. The main predictor is the continuous change in phase angle, and the main outcome is at least one Clavien-Dindo grade II-V complication within 30 days. A supportive analysis will compare clinical outcomes with 240 consecutive historical controls using existing hospital records. The historical controls do not receive the study procedure and are not included in the prospective enrollment.
Detailed description
The prospective component is protocol-assigned, non-randomized, open-label, and single-group. Dosing weight is the lower of actual body weight measured at T0 and ideal body weight calculated from sex and height using the Robinson equations. An eGFR of at least 60 mL/min/1.73 m² is an eligibility criterion and is not used to calculate fluid volume. From infusion start through T60, food, drink, and other intravenous fluids are withheld unless clinically required. Routine walking to the toilet and standing scale is permitted. Only T0 and T60 research BIA measurements are performed. Clinical care takes priority over the protocol, and symptoms or clinician concern require stopping the infusion and performing a medical assessment. Short-term outcomes are assessed through 90 postoperative days. Long-term outcomes include overall survival and, in participants with malignant disease, recurrence-free survival for up to five years. The complete ambispective research program also includes 240 consecutive eligible patients operated on immediately before implementation of the prospective protocol. Their data are obtained retrospectively from existing University Hospital of Split records without contact or additional procedures, under the approved waiver of consent. This historical comparison is not a prospectively assigned ClinicalTrials.gov arm and is not included in the anticipated enrollment of 120.
Interventions
DRUGIonolyte Balanced Isotonic Crystalloid
Ionolyte is administered intravenously at 15 mL/kg dosing weight, up to a maximum of 1,000 mL, over exactly 40 minutes. Dosing weight is the lower of actual body weight measured at T0 and ideal body weight calculated from sex and height using the Robinson equations. The infusion rate in mL/h equals the total volume multiplied by 1.5.
Sponsors
University Hospital of Split
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
All participants receive the same standardized preoperative Ionolyte infusion and undergo BIA measurements at T0 and T60; there is no concurrent control arm.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 18 years or older * Scheduled for elective colon or rectal resection at University Hospital of Split * Written informed consent before research-specific procedures * Able to stand safely and complete both BIA measurements * Preoperative eGFR at least 60 mL/min/1.73 m² * Clinically eligible for the protocol fluid volume
Exclusion criteria
* Emergency surgery * eGFR below 60 mL/min/1.73 m² or oliguria * Heart failure or clinically significant cardiac disease making fluid loading inappropriate * Edema, pulmonary congestion, or clinically significant ascites * Active implantable electrical device * Limb amputation, inability to undergo standardized standing BIA, or unsafe standing * Clinically significant electrolyte abnormality * Pregnancy * Contraindication to Ionolyte or any clinician safety concern * Inability to provide valid informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Participants With at Least One Clavien-Dindo Grade II-V Postoperative Complication | From surgery through postoperative day 30 | Number and proportion of participants experiencing at least one postoperative complication graded II, III, IV, or V according to the Clavien-Dindo classification. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Phase Angle | T0 to 60 minutes after infusion start | Whole-body/software-reported phase angle at T60 minus T0, analyzed continuously. |
| Change in Extracellular Water | T0 to 60 minutes after infusion start | Extracellular water at T60 minus extracellular water at T0, measured in kilograms and analyzed continuously. |
| Major Postoperative Complications | Through postoperative day 30 | Participants with at least one Clavien-Dindo grade III-V complication. |
| Comprehensive Complication Index | Through postoperative day 30 | Cumulative postoperative morbidity on the 0-100 CCI scale; higher scores indicate greater morbidity. |
| Surgical-Site Infection | Through postoperative day 30 | Participants meeting the protocol-defined surgical-site infection criteria. |
| Anastomotic Leakage | Through postoperative day 30 | Participants with clinically and/or radiologically diagnosed anastomotic leakage according to the protocol definition. |
| Number of Participants With Acute Kidney Injury | From surgery through postoperative day 30 | Participants meeting KDIGO acute kidney injury criteria based on available creatinine and/or valid routine urine-output data. |
| Length of Hospital Stay | From colon or rectal resection through discharge from the hospitalization during which the resection was performed, up to 90 days after surgery | Number of days from the colon or rectal resection to discharge from the hospitalization during which the resection was performed. |
| Number of Participants With an Unplanned Reoperation | Through postoperative day 30 | Participants undergoing an unplanned reoperation. |
| Number of Participants With Hospital Readmission | Through postoperative day 30 | Participants readmitted after discharge. |
| All-Cause Mortality | Postoperative days 30 and 90 | All-cause mortality reported separately at 30 and 90 days. |
| Overall Survival | Up to 5 years after surgery | Time from surgery to death from any cause; living participants are censored at last known follow-up. |
| Recurrence-Free Survival | Up to 5 years after surgery | For malignant disease with available follow-up, time from surgery to documented recurrence or death according to the statistical analysis plan definition. |
| Change in Intracellular Water | T0 to 60 minutes after infusion start | Intracellular water at T60 minus intracellular water at T0, measured in kilograms and analyzed continuously. |
| Change in Total Body Water | T0 to 60 minutes after infusion start | Total body water at T60 minus total body water at T0, measured in kilograms and analyzed continuously. |
| Change in Extracellular Water to Total Body Water Ratio | T0 to 60 minutes after infusion start | The device-reported ECW/TBW ratio at T60 minus the ratio at T0, analyzed continuously. |
| Change in Whole-Body Resistance at 50 kHz | T0 to 60 minutes after infusion start | Whole-body resistance at 50 kHz at T60 minus resistance at T0, measured in ohms and analyzed continuously. |
| Change in Whole-Body Reactance at 50 kHz | T0 to 60 minutes after infusion start | Whole-body reactance at 50 kHz at T60 minus reactance at T0, measured in ohms and analyzed continuously. |
| Change in Body Weight | T0 to 60 minutes after infusion start | Body weight at T60 minus body weight at T0, measured in kilograms and analyzed continuously. |
Countries
Croatia
Contacts
CONTACTOgnjen Barcot, MD, PhD
PRINCIPAL_INVESTIGATORPetra Nizeteo, MD
University Hospital of Split
Outcome results
None listed