Short summary

Intravenous fluid administration during abdominal surgery is lifesaving. Too little fluid administration results in hypovolemia, decreased organ perfusion and circulatory shock. Too much fluid given increases postoperative complications and worsens pulmonary and cardiac functions. Perioperative individualized Goal Directed fluid Therapy (GDT) and zero-balance therapy (weight adjusted) has shown beneficial outcome for planned surgery, but has never been tested in urgent abdominal surgery. The aim of the GAS-ART trial is to investigate whether perioperative GDT and postoperative zero balance fluid therapy can improve postoperative morbidity and mortality compared to standard fluid therapy for acute gastrointestinal surgical patients.

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Rationale

Urgent surgery for perforated and obstructive bowel disease is lifesaving. Survival without operation is close to zero but even with operation survival is far from 100%. In a Danish study 30-day survival after urgent abdominal surgery was 84.3% for patients undergoing colonic surgery. In another Danish study 81.8% of the patients operated for perforated ulcers were alive after 30 days.

The primary cause of death is the intraabdominal disease, but complications after surgery such as heart failure, pneumonia, sepsis, anastomosis leakage, renal failure and thromboembolic events play an important role.

Hypovolemia and untreated circulatory shock will lead to death and intravenous fluid is a lifesaving treatment. Therefore considerable fluid infusion is given. On the other hand studies have shown that too much fluid is harmful and impacts complications.

The circulatory status of the patient is usually based on variables such as blood pressure, heart rate, diuresis, venous oxygenation and clinical observations. Parameters as these have shown to be poor in the guidance of fluid therapy. Individualized goal directed fluid therapy (GDT) uses stroke volume to guide fluid administration during surgery and can limit over hydration. Likewise, the perioperative zero-balance approach, replacing only physiologic and pathologic loss combined with bodyweight measures to guide fluid therapy, can limit excessive fluid administration. Both approaches have shown reduced postoperative complications but have never been tested for patients undergoing urgent surgery.

The aim of the GAS-ART trial is to investigate whether perioperative GDT and postoperative zero balance fluid therapy can improve postoperative morbidity and mortality compared to standard fluid therapy for acute gastrointestinal surgical patients.

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Description of the cohort

GAS-ART is a clinical randomized multicenter trial with stratification for each center and for laparotomy vs. laparoscopy. 

Patients in the trial

Included are all adult patients with a need for urgent abdominal surgery due to perforation of the intestine or obstructive bowel disease. The surgical procedure must be carried out 6 hours from the decision has been taken.

Excluded are children, pregnant women, patients unable to give consent, patients in dialysis, ASA 5 and patients who had surgery within a month.

Data and biological material

The thesis is that the total intravenous fluid volume given affects postoperative mortality and complications.

Primary end point is all-cause mortality and major postoperative complications registered on 30^th and 90^th day postoperative. Other variables registered are miner complications, fluid administrations and time trends during the patient's course in the trial.

Collaborating researchers and departments

Department of Surgery, Holbæk Sygehus

• Principal investigator Anders Voldby, MD

Department of Surgery, Slagelse Hospital

• Investigator Kenneth Rütz, MD

Department of Surgery, Svendborg Hospital

• Investigator Panteha Khodadadeh, MD

Department of Surgery, Odense University Hospital

• Investigator Erik Zimmermann-Nielsen, MD

Department of Surgery, Herlev Hospital

• Investigator Nicolas Storm, MD