Table 3 Postoperative pulmonary complication diagnostic tool

PPCs

For the purposes of this study PPC will be diagnosed by presence of 4 or more of the following:

1. Chest radiograph report of atelectasis/consolidation. In the event of no CXR being taken, the CXR report from the previous postoperative day will be used. If neither are available a not available will be reported (n/a). If a CXR report is not available but a CXR has been taken a ward medical officer will be asked to report on this should this be the defining criteria for PPC.

2. An otherwise unexplained WCC of >11.2 × 10⁹/L or administration of respiratory antibiotics postoperatively (in addition to those administered routinely postoperatively). In the event of no WCC being taken, the WCC report from the previous postoperative day will be used. If none of these are available a n/a will be reported

3. Fever as seen by raised oral temperature >38°C with no focus outside of the lungs. The highest temperature within the previous 24 hours will be reported.

4. Positive signs of infection on sputum microbiology.

5. Production of purulent (yellow or green) sputum differing from preoperative status

6. SpO₂ < 90% on room air (see measurement protocol below).

7. Diagnosis of pneumonia/chest infection by attending physician.

8. Re-admission to the ITU/HDU with problems which are respiratory in origin or a prolonged stay on the ITU/HDU (over 36 hours) with problems which are respiratory in origin.

Sp0 ₂ measurement

All SpO₂ measurements will be taken in the morning prior to physiotherapy treatment. Prior to measurement of SpO₂:

▪ The patient will be positioned in upright sitting (or long sitting if unable to be out of bed).

▪ O₂ therapy will be withdrawn for a period of 5 minutes & SpO₂ will be monitored but not recorded during this time. NB if patient on room air allow monitor to stabilise for 1 minute prior to reading.

▪ Measurement will be by designated pulse oximeter via a finger probe.

▪ After 5 minutes the SpO₂ will be measured by reapplying the finger sensor to the index finger of one hand for 30 seconds.

▪ The lowest SpO₂ during the 30 second measuring period will be recorded.

▪ If a patient's SpO₂ drops below 88% at any stage of the measures they will be immediately returned to supplemental O₂ as prescribed and measures abandoned. This will be noted and the value recorded.

▪ If the SpO₂ drops below 90% (i.e. 89% or below) this will be noted as achieving as one of the criteria for PPC.

▪ Only patients with an SpO₂ of 89% or below will not be taken off oxygen for SpO₂ monitoring purposes (i.e. these patients will have already achieved criteria for PPC without removal from O₂).

▪ If the physiotherapists notes the hands to be cool, peripheral shutdown, poor pulsatile flow on the SpO₂ monitor or a dampened trace this will be recorded as being unreliable (N). A reliable trace will be recorded as (Y).