Effects of intraoperative PEEP optimization on postoperative pulmonary complications and the inflammatory response: study protocol for a randomized controlled trial

Abstract

Background: Patients undergoing general anesthesia and mechanical ventilation during major abdominal surgery commonly develop pulmonary atelectasis and/or hyperdistention of the lungs. Recent studies show benefits of lung-protective mechanical ventilation with the use of low tidal volumes, a moderate level of positive end-expiratory pressure (PEEP) and regular alveolar recruitment maneuvers during general anesthesia, even in patients with healthy lungs. The purpose of this clinical trial is to evaluate the effects of intraoperative lung-protective mechanical ventilation, using individualized PEEP values, on postoperative pulmonary complications and the inflammatory response.

Methods/design: A total number of 40 patients with bladder cancer undergoing open radical cystectomy and urinary diversion (ileal conduit or orthotopic bladder substitute) will be enrolled and randomized into a study (SG) and a control group (CG). Standard lung-protective ventilation with a PEEP of 6 cmH2O will be applied in the CG and an optimal PEEP value determined during a static pulmonary compliance (Cstat)-directed PEEP titration procedure will be used in the SG. Low tidal volumes (6 mL/Kg ideal bodyweight) and a fraction of inspired oxygen of 0.5 will be applied in both groups. After surgery both groups will receive standard postoperative management. Primary endpoints are postoperative pulmonary complications and serum procalcitonin kinetics during and after surgery until the third postoperative day. Secondary and tertiary endpoints will be: organ dysfunction as monitored by the Sequential Organ Failure Assessment Score, in-hospital stay, 28-day and in-hospital mortality.

Discussion: This trial will assess the possible benefits or disadvantages of an individualized lung-protective mechanical ventilation strategy during open radical cystectomy and urinary diversion regarding postoperative pulmonary complications and the inflammatory response.

Trial registration: ClinicalTrials.gov, ID: NCT02931409 . Registered on 5 October 2016.

Keywords: Lung-protective ventilation; Positive end-expiratory pressure; Postoperative pulmonary complications; Procalcitonin; Radical cystectomy; Static pulmonary compliance.

Conflict of interest statement

Authors’ information

Not applicable.

Ethics approval and consent to participate

The study was approved by the Hungarian Scientific and Medical Research Council Ethics Committee (Egészségügyi Tudományos Tanács Tudományos Kutatás Etikai Bizottság ETT-TUKEB; chairperson: Professor Dr. Zsuzsanna Schaff; registration number 21586-4/2016/EKU) on 17 June 2016 and the Local Ethics Committee of Péterfy Sándor Hospital Budapest (Péterfy Sándor utcai Kórház Intézeti Kutatásetikai Bizottság IKEB; chairperson: Dr. Mária Vas; registration number CO-338-045) on 12 September 2016 and the Regional Ethics Committee of the University of Szeged (Regionális Humán Orvosbiológiai Tudományos és Kutatásetikai Bizottság RKEB; chairperson: Dr. Tibor Wittmann; registration number 149/2016-SZTE) on 19 September 2016. This study is conducted in accordance with the Declaration of Helsinki and was prospectively registered on 5 October 2016 at Participants fulfilling the inclusion criteria will sign an Informed Consent Form during their perioperative assessment. Withdrawal of consent may be initiated by the participant at any time during the trial.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

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Figures

Fig. 1

Standard Protocol Items: Recommendation for Interventional Trials (SPIRIT) schedule of enrollment, interventions and assessments. DOS day of surgery, POD postoperative day, SOFA Sequential Organ Failure Assessment, ICU intensive care unit

Fig. 2

Consolidated Standards of Reporting Trials (CONSORT) flowchart. PEEP positive end-expiratory pressure, PCT procalcitonin, ABGs arterial blood gas sample, CVBGs central venous blood gas sample, Cstat static pulmonary compliance, Vds/Vt dead space fraction, Raw airway resistance, MAP mean arterial pressure, ARM alveolar recruitment maneuver, PRBC packed red blood cell, FFP fresh frozen plasma, IAP intraabdominal pressure