COMparison of Portable Fingertip Versus Conventional Pulse OximeteRs Trial

The purpose of this prospective, quantitative study is to compare the agreement between the measured arterial oxygen saturation levels using a portable fingertip versus a conventional bedside pulse oximeter in adult surgical patients, presenting for elective and emergency surgery to Groote Schuur Hospital over a four-week period. Adult surgical patients, not meeting any exclusion criteria, who present for elective or emergency surgery will be recruited. 200 data pairs (SpO2, heart rate and skin tone) will be recorded in the perioperative period (operating rooms, recovery room and intensive care unit).

Existing monitoring devices will not be disturbed. The agreement between the two devices will be compared using a Bland-Altman plot, Microsoft Excel and SPSS software. A root mean square difference value will also be calculated from these values.

No sensitive or personal patient information will be recorded, and pulse oximetry is essential harmless. Potential cross-infection will be avoided by excluding patients with known communicable diseases or open wounds/ bodily fluids in the area to have the oximeter probes applied. The study devices will be disinfected after each use. Recruitment will not affect clinical care.

The significance of this study into the performance of portable fingertip pulse oximeters in adult surgical patients will result in the availability of cheaper devices, deemed as vital anaesthetic equipment by the WHO and various anaesthetic regulatory bodies, in lower income medical facilities. It will also give anaesthetists and other medical personal the confidence to make clinical decisions based on these highly portable devices, thereby making pulse oximeters more available in resource limited areas. It will also add further data to existing studies and help assess whether darker skin pigment affects the performance of these devices in the clinical setting, which is highly relevant in an African country like South Africa.

Inclusion criteria

• Adult surgical patients presenting for elective or emergency surgery

Exclusion criteria

• Contact precautions due to high risk of transmissable infectious disease
• Significant hypotension or hypoperfusion (systolic blood pressure <80 mmHg, or hypothermia)
• Motion artefacts due to excessive patient movements
• Known presence of variant haemoglobin species (eg. carboxy- or methaemoglobin)
• Intraoperative dye use (eg. methylene blue or indocyanine green)
• Nail polish or black henna
• Tape or bandages over the fingers
• Absent/inadequate pulse oximetry tracing on existing monitor