Laparoscopic surgery of the distal colon and rectum requires surgery with an appropriate field of view. A commonly used technique to create a clear exposure is the steep Trendelenburg position in which the patient is positioned in an angle of 15 to 40 degrees with the head down using the effect of gravity to retract the small intestine. This method is associated with haemostatic changes caused by the cranial shift of abdominal organs and blood. Recently, a cellulose compressed sponge was developed as intraoperative retractor, with the aim to keep the small intestines aside while the patient remains in a horizontal position. The safety of the sponge is secured with CE marking. The retractor sponge ensures a clear surgical field and potentially prevents haemostatic instability by avoiding Trendelenburg position. A pilot study in the St Antonius Hospital Nieuwegein has shown that use of the sponge might be associated with shorter hospital stay.

Objective: We study the efficacy of the retractor sponge in laparoscopic colorectal surgery to reduce hospital stay in patients operated for a malignancy. Secondary objectives are duration of surgery, blood-loss, use of diuretics as volume therapy (during surgery as wells as during total hospital stay), postoperative hypoxemia and peri- and postoperative complications.

Study design: Randomized controlled trial, nested within a prospective cohort according to the 'cohort multiple randomized controlled trial' (cmRCT) design.

Study population: Patients with colorectal cancer who undergo laparoscopic surgery, and who have given informed consent to be offered experimental interventions within the PICNIC project. Patient who require open surgery or patients with benign colorectal diseases are excluded for this study.

Intervention: Intraoperative use of the retractor sponge versus usual care, i.e. the Trendelenburg position.

Main study parameters/endpoints: The primary endpoint is length of hospital stay. Secondary endpoints are duration of surgery, blood-loss, use of diuretics (during surgery as wells as during total hospital stay), postoperative hypoxemia and peri- and postoperative surgical, pulmonary and cardiac complications.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The study will be conducted according to the cohort multiple Randomized Controlled Trial (cmRCT) design. Within the PICNIC cohort, we will identify all patients who are eligible for the experimental intervention (use of the sponge) and who have given informed consent to be invited for future experimental interventions. From this sub cohort, we will randomly select a group of patients to whom we will offer surgery with use of the retractor sponge, which they can accept or decline. Eligible patients from the sub cohort who were not randomly selected will undergo standard treatment, i.e. surgery in Trendelenburg position. We do not expect adverse events in patients in the intervention arm, besides dysfunction of the sponge, after which conversion to standard treatment (Trendelenburg position) needs to take place.

Inclusion criteria:

• Participant in the PICNIC project (METC 12-510)
• Informed consent obtained for being offered experimental interventions within the PICNIC project
• Informed consent obtained for questionnaires on patient reported outcomes within the PICNIC project
• Planned for laparoscopic surgery of distal colorectal cancer in St. Antonius Hospital

Exclusion Criteria:

• Planned for open colorectal surgery
• Surgery for benign colorectal diseases
• Emergency colorectal surgery
• Inadequate understanding of the Dutch language in speech and/or writing