Investigating Oximetry and Capnography To assess impact of Opiate Infusions on Patients Undergoing Palatoplasties

Investigating Oximetry and Capnography To assess impact of Opiate Infusions on Patients Undergoing Palatoplasties


CIA: Professor Britta Regli-von Ungern-Sternberg

Project summary

Whilst oximetry is regularly measured in patients post-palatoplasty, carbon dioxide monitoring is not a feature of the standard monitoring that palatoplasty patients receive. The overnight ventilation profile of palatoplasty patients is therefore unknown. Whilst SpO2 can be used in these patients to assess oxygenation, it has been shown that this alone does not fully represent a patient’s respiratory status. The vulnerability of this patient group together with the use of opiate infusions makes this a major gap in our understanding of their treatments.
Aims and Hypotheses
This pilot study aims to gather information on oxygenation and ventilation measurements in infants on prescribed opioid infusions after palatoplasty repair. As a pilot study we hypothesise that we will be able to successfully recruit eligible participants and effectively carry out monitoring of oxygenation and ventilation to gather information on the respiratory status on patients immediately post palatoplasty surgery.

  • To assess the rate of successful participant recruitment and adherence to the protocol without deviation (recruitment rate of >30% of eligible patients and adherence to protocol of >70%).
  • To assess the viability of the assessment of overnight oxygenation and ventilation in infants post-palatoplasty. 
  • To evaluate oxygenation and ventilation in infants following cleft palate repair.
  • To compare standard ward monitoring and continuous oximetry and capnography monitoring for their ability to identify opiate induced ventilatory impairment.
  • ​Acceptability of study procedures to ward clinical staff of >80%.

Patients will have their overnight oximetry monitored for 3 nights pre-operatively at home with a Nonin wrist-worn oximeter (WristOx 3150, Nonin Medical, Plymouth, MN). The Nonin WristOx 3150 is a small, lightweight pulse oximeter designed to be worn comfortably on the patient’s wrist or ankle and is ideal for use in the patient’s home. Pre-operative monitoring will be completed within 8 weeks of the patient’s surgery date.
On the day of surgery relevant information on the patient’s demographics and medical history will be collected. Parents will be asked to complete a brief questionnaire on their child’s sleeping habits pre-operatively. Continuous monitoring of oxygen will commence within an hour of the patient being connected to their post-operative opiate infusion. Oximetry data will be obtained using the same Nonin WristOx 3150. Transcutaneous CO2 (tcCO2) and measured overnight using the SenTec digital monitoring system (SenTec, Lincoln, RI 02685 United States) via a probe connected to the patient’s forehead or shoulder. TcCO2 sensors will be connected within two hours of the patient’s normal bedtime, on the night of surgery. Both sensors will be removed 12 hours after the tcCO2 sensor is placed. These post-operative measurements will be performed in addition to standard ward monitoring.
Likely benefits of the research
This study will provide novel evidence on the feasibility and value of continuous, concurrent oxygenation and ventilation monitoring on infants post-palatoplasty. The results of this study will inform future research into the effects of opiate infusions on patients recovering from palatoplasty so that the impacts of such treatments can be better understood.

Chief investigators

Professor Britta Regli-von Ungern-Sternberg
Dr David Gillett
Perth Children’s Hospital, Western Australia.



The project was awarded A$70,000 funding through the ANZCA research grants program for 2024.   

Last updated 10:50 15.12.2023