Respiratory Effects of Perioperative Oxygen During General Anaesthesia

University of Copenhagen35 enrolled

Overview

Aim: To investigate the effect of high intra- and postoperative oxygen concentration (80%, as opposed to normally 30%) on pulmonary gas exchange and other pulmonary complications after abdominal surgery. Background: Previous studies have shown possible beneficial effects of high perioperative oxygen concentration on surgical wound infection and healing, but all pulmonary effects are not clarified. Change in perioperative PaO2/FiO2 and shunt-fraction, measured by a gas rebreathing technique, can describe pulmonary oxygenation. This could add knowledge to the pulmonary effects of high vs. normal oxygen concentration. Primary hypothesis of study: Perioperative use of a 80% oxygen concentration reduces the PaO2/FiO2-index compared to 30% oxygen.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Enrollment

Conditions

Laparotomy

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age 18 years or older * Laparatomy, elective Exclusion Criteria: * Inability to give informed consent * Chemotherapy within 3 months * Other surgery within 30 days(except surgery in local anaesthesia) * Inability to keep oxygen saturation above 90% without supplemental oxygen (measured preoperatively by pulse oximetry)

Outcomes

Primary Outcomes

Change in PaO2/FiO2-index during general anaesthesia.

Time frame: End of surgery.

Secondary Outcomes

Change in PaO2/FiO2-index during general anaesthesia and postoperative recovery.

Time frame: 1½ hour after surgery.

Atelectasis and Pneumonia

Time frame: 14 days after surgery

Arterial oxygen saturation

Time frame: 2 hours and 3 days after surgery.

Change in functional residual capacity (FRC)

Time frame: 2 hours after surgery.

Change in effective pulmonary bloodflow

Time frame: 2 hours after surgery.