Can Biomarkers Aid in the Prediction of Postoperative Pain and Circulatory Instability After Major Abdominal Surgery?

Study Overview
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Brief Summary
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Patients undergoing major surgery are exposed to extensive damage of tissues, which induces widespread activation of the inflammatory system, called 'systemic inflammatory response syndrome' (SIRS).This activation of the inflammatory system may induce instability of the heart and respiration in the postoperative period. The degree of physiologic response to postoperative SIRS as well as the degree of postoperative pain differ between patients. Therefore, patients undergoing anesthesia and major surgery are treated in a 'post anesthesia care unit' (PACU) after end of surgery.Admittance to a PACU is expensive. The time patients need to stay in a PACU after major surgery has not been extensively studied, and more appropriate tools for prediction of length of stay are needed. The main aim of this study is to assess whether clinical observations, inflammatory biomarkers or genetic markers may aid in the prediction of physiological instability and/or pain after major surgery. Such predictors would help clinicians planning the length of PACU-stays.

Official Title
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Can Biomarkers Aid in the Prediction of Postoperative Pain and Circulatory Instability After Major Abdominal Surgery? A Prospective Observational Study

Conditions
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Systemic Inflammatory Response Syndrome

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing major abdominal surgery (e.g. Whipple's operation, liver resection, abdominoperineal resection, vascular abdominal surgery etc.) Scheduled for PACU stay first 24 hours Exclusion Criteria: Pregnancy Jehovah's witness Dementia

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Major abdominal surgery<br>Patients undergoing major abdominal surgery (laparotomy). Surgical procedures considered for inclusion include, but are not restricted to, procedures such as gastrectomy, pancreatic surgery, liver resection, open prostatectomy, colonic surgery, radical cystectomy with ileal conduit, open nephrectomy and vascular abdominal aortic surgery. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to established circulatory stability for > 2 hours [Time to event outcome] | Circulatory stability will be assessed by applying a multi-state statistical model, where any state changes are measured at an hourly basis. The model will include variables reflecting the circulatory state of the patient, including heart rate, systolic blood pressure (or MAP) and lactate, which will be assessed together with the measures needed to maintain them, such as the amount of fluid given (ml per hour) and the extent of vasopressor (i.e. norepinephrine). The main outcome variable will be the time needed to reach the state of 'stable without intervention for more than two hours. To be classified in this state, the systolic blood pressure must be > 100 mmHg, the heart rate between 40 and 110, the patient must be off vasopressor and has a fluid requirement of less than 250 ml/hour. | 48 hours | 
| Time to reaching a state of no or mild pain problem for > 2 hours [Time to event outcome] | This outcome will be reached when the patient has a numeric rating score (NRS) with respect to pain of < 4 and the opioid consumption is less than 5 mg morphine equivalents per hour. | 48 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Abdomen/surgery, Biological markers, Length of stay, Postoperative care, Anesthesia recovery period, Prognosis