(65 days)
The M1196A and M1196T reusable Clip sensors provide continuous, non-invasive measurement of arterial oxygen saturation (pulse rate signal and plethysmograph wave) to any SpO2 device that has passed validation testing. Either sensor can be comfortably clipped onto the finger of patients weighing > 40 kg (typically adult patients).
The Philips SpO2 devices measure, non-invasively, the arterial oxygen saturation of blood. The measurement method is based on the red and infrared light absorption of hemoglobin and oxyhemoglobin. Light of a red and infrared light source is emitted through human tissue and received by a photodiode.
The measurement is based on the absorption of light, which is emitted through human tissue (for example through the index finger). The light comes from two sources (red LED and infrared LED) with different wavelengths and is received by a photodiode. Out of the different absorption behavior of the red and infrared light a so-called Ratio can be calculated. The saturation value is defined by the percentage ratio of the oxygenated hemoglobin [HbO2] to the total amount of hemoglobin [Hb].
SpO2 = [HbO2]/([Hb]+[HbO2])
Out of calibration curves, which are based on controlled hypoxia studies with healthy non-smoking adult volunteers over a specified saturation range (SaO2 from 100%-70%), the Ratio can be related to a SpO2 value.
The devices contain a red and infrared light source and a photodiode receiving the non-absorbed red and infrared light. The received signals are forwarded to a measurement device that amplifies the acquired signal and an algorithm that calculates the ratio and converts via a validated calibration table the ratio to a saturation value.
Here's an analysis of the provided text, focusing on acceptance criteria and the study details for the Philips SpO2 Pulse Oximeter Sensor:
Acceptance Criteria and Study for Philips SpO2 Pulse Oximeter Sensor (Models M1196A and M1196T)
Based on the provided 510(k) summary, the device is a modified version of an existing device, with the modification being a change in housing design from a soft cuff to a clip style. The primary focus of the testing described is to demonstrate substantial equivalence to the predicate device, particularly regarding accuracy.
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state numerical acceptance criteria in a table format, nor does it provide specific quantitative performance metrics beyond the description of the study. However, the basis for performance evaluation is described:
| Acceptance Criteria (Inferred) | Reported Device Performance |
|---|---|
| SpO2 Accuracy (across 70-100% range) | Established through "controlled hypoxia studies with healthy non-smoking adult volunteers" |
| Substantial Equivalence | "Design verification and validation test results confirmed that the device is substantially equivalent with the identified predicate devices." |
| Environmental Performance | "Verification and validation testing activities were conducted to establish the performance and reliability characteristics of the modified device." |
| Hardware and Cable Interface Verification | "Hardware verification testing and cable interface verification testing were also conducted." |
2. Sample Size for the Test Set and Data Provenance
- Sample Size: Not explicitly stated as a numerical sample size. The description refers to "healthy non-smoking adult volunteers."
- Data Provenance: Prospective. The studies were "controlled hypoxia studies" which are inherently prospective. The country of origin is not explicitly stated, but the submission is to the FDA in the US, suggesting the study likely took place in the US or under US regulatory guidelines.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- Number of Experts: Not applicable/not mentioned. This type of device relies on direct physiological measurement, and the "ground truth" (SaO2) in hypoxia studies is typically measured by co-oximetry of arterial blood samples, not by expert consensus.
- Qualifications of Experts: Not applicable for establishing ground truth for direct physiological measurements.
4. Adjudication Method for the Test Set
- Not applicable. Adjudication is typically used for image interpretation or subjective assessments. Here, the comparison is of the device's SpO2 reading against a direct physiological measurement (SaO2 from blood gas analysis).
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, a MRMC study was not done. This type of study involves evaluating human readers' performance with and without AI assistance, which is not relevant for a standalone SpO2 sensor device.
6. Standalone Performance Study
- Yes, a standalone study was done. The "controlled hypoxia studies" assessed the device's ability to accurately measure SpO2 against a known reference (SaO2 from arterial blood samples) in a controlled environment. The phrase "algorithm that calculates the ratio and converts via a validated calibration table the ratio to a saturation value" implies an algorithm-only performance.
7. Type of Ground Truth Used
- The ground truth used was physiological outcome data, specifically arterial oxygen saturation (SaO2), derived from co-oximetry of arterial blood samples during the controlled hypoxia studies. This is explicitly stated as "SaO2 from 100%-70%".
8. Sample Size for the Training Set
- Not explicitly stated. The "calibration curves, which are based on controlled hypoxia studies" suggest that data from these studies were used to establish the device's calibration. It is implied that the same or similar controlled hypoxia studies provided the data for both calibration (training) and validation (testing), or that a subset was used for training/calibration.
9. How the Ground Truth for the Training Set Was Established
- The ground truth for establishing the calibration curves (training set) was established through controlled hypoxia studies with healthy non-smoking adult volunteers. In these studies, subjects were desaturated to various levels of arterial oxygen saturation (SaO2), and the SpO2 values from the device were correlated with directly measured SaO2 values obtained from co-oximetry of arterial blood samples. This process allows for the creation of a "validated calibration table" that relates the device's measured optical ratio to a SpO2 value.
§ 870.2700 Oximeter.
(a)
Identification. An oximeter is a device used to transmit radiation at a known wavelength(s) through blood and to measure the blood oxygen saturation based on the amount of reflected or scattered radiation. It may be used alone or in conjunction with a fiberoptic oximeter catheter.(b)
Classification. Class II (performance standards).