Intraoperative Lung Protective Ventilation Needs Periodic Lung Recruitment Maneuvers

Rate of mild respiratory failure

Mild respiratory failure: PaO2 \< 60 mmHg or pulse oxygen saturation (SpO2) \< 90% on room air, but SpO2 can be raised to more than 90% when inhaling oxygen through nasal catheter less than 3 L/min.

Time frame: Day 0 to 7 after surgery

Rate of moderate respiratory failure

Moderate respiratory failure: PaO2 \< 60 mmHg or SpO2 \< 90% when inhaling oxygen through nasal catheter less than 3 L/min, but SpO2 can be raised to more than 90% when inhaling oxygen more than 3 L/min.

Time frame: Day 0 to 7 after surgery

Rate of severe respiratory failure

Severe respiratory failure: experienced an invasive or noninvasive ventilator therapy, or PaO2 \< 60 mmHg or SpO2 \< 90% when administering oxygen via a nasal catheter at 3 L/min or more.

Time frame: Day 0 to 7 after surgery

Rate of sustained hypoxaemia

Sustained hypoxaemia: during a follow-up visit when the patient was awake and breathing room air, SpO2 ≤ 92% or the change of SpO2 (ΔSpO2, preoperative SpO2 minus postoperative SpO2) ≥ 5% on any three consecutive days.

Time frame: Day 0 to 7 after surgery

Rate of modified respiratory failure

Modified respiratory failure: met the criterion of moderate or severe respiratory failure, or mild respiratory failure in twice follow-up, or mild respiratory failure with sustained hypoxemia.

Time frame: Day 0 to 7 after surgery

Rate of respiratory infections

Respiratory infections: receiving antibiotics for a suspected respiratory infection and met at least one of the following criteria: new or changed sputum, new or changed lung opacities, fever, leukocyte count \>12 × 109 /L

Time frame: Day 0 to 7 after surgery

Rate of pneumonia

Pneumonia: United States Centers for Disease Control definition of pneumonia

Time frame: Day 0 to 7 after surgery

Rate of aspiration pneumonitis

Aspiration pneumonitis: acute lung injury after the inhalation of regurgitated gastric contents.

Time frame: Day 0 to 7 after surgery

Rate of pneumothorax

Pneumothorax: air in the pleural space with no vascular bed surrounding the visceral pleura

Time frame: Intraoperative or day 0 to 7 after surgery

Rate of pleural effusion

Pleural effusion: chest radiograph demonstrating blunting of the costophrenic angle, loss of sharp silhouette of the ipsilateral hemidiaphragm in upright position, evidence of displacement of adjacent anatomical structures or (in supine position) a hazy opacity in one hemithorax with preserved vascular shadows

Time frame: Day 0 to 7 after surgery

Rate of Acute Respiratory Distress Syndrome

Acute Respiratory Distress Syndrome: The Berlin definition of Respiratory Distress Syndrome

Time frame: Day 0 to 7 after surgery

Rate of Quick Sequential Organ Failure Assessment (qSOFA) ≥ 2

qSOFA ≥ 2: Two or more of: Respiratory rate ≥22/min, Altered mentation, Systolic blood pressure ≤ 100 mm Hg

Time frame: Day 0 to 7 after surgery

Rate of Systemic Inflammatory Response Syndrome (SIRS)

SIRS: Two or more of: Temperature \>38°C or \<36°C, Heart rate \> 90/min, Respiratory rate \>20/min or PaCO2\<32 mmHg (4.3kPa), White blood cell count \>12 000/mm3 or 10% immature bands

Time frame: Day 0 to 7 after surgery

Rate of Major Adverse Cardiac and Cerebrovascular Events (MACCE)

MACCE: Stroke, coma, non-fatal cardiac arrest, acute myocardial infarction, congestive heart failure.

Time frame: Day 0 to 7 after surgery

Postoperative hospitalization days

The duration between the operation date and the actual discharge date, days

Time frame: Day 0 to 30 after surgery

Rate of Unexpected admission to intensive care unit (ICU)

Unexpected admission to ICU: It does not include patients who enter ICU at the request of surgeons but have normal spontaneous breathing, stable circulation and no disturbance of consciousness.

Time frame: Day 0 to 30 after surgery

Rate of death

Death from any cause

Time frame: Day 0 to 30 after surgery

Rate of intraoperative hypotension

Intraoperative hypotension: mean arterial pressure (MAP) \< 60 mmHg lasting more than 3 minutes

Time frame: Intraoperative, period of mechanical ventilation

Rate of intraoperative needing for vasoconstrictor

Intraoperative vasoconstrictor needs: MAP \< 60 mmHg and using any catecholamines

Time frame: Intraoperative, period of mechanical ventilation

Rate of intraoperative hypoxemia

Intraoperative hypoxemia: SpO2 ≤ 92% lasting more than 3 minutes

Time frame: Intraoperative, period of mechanical ventilation

Rate of Intraoperative bradycardia

Intraoperative bradycardia: heart rate ≤ 50 bpm and the decrease of heart rate from the basic value ≥ 20% lasting more than 3 minutes

Time frame: Intraoperative, period of mechanical ventilation

Rate of post-anesthesia care unit respiratory failure

Post-anesthesia care unit respiratory failure: PaO2 \< 8 kPa (60 mmHg) on room air, a PaO2:FI02 ratio \< 40 kPa (300 mmHg) or arterial oxyhaemoglobin saturation measured with pulse oximetry \< 90% and requiring oxygen therapy

Time frame: Postoperative, during postanesthesia care unit

Intraoperative mechanical power

Mechanical power, J/min

Time frame: Intraoperative: after half an hour of mechanical ventilation, before the end of mechanical ventilation

PaO2 / FI02

PaO2 / FI02, mmHg

Time frame: Intraoperative: after half an hour of mechanical ventilation, before the end of mechanical ventilation

Postoperative pulmonary complications score

Postoperative pulmonary complications score: graded on a scale from 0 (no pulmonary complications) to 4 (the most severe complications).

Time frame: Day 0 to 7 after surgery