(89 days)
The intended use of the N-395 Pulse Oximeter is the continuous, non-invasive monitoring of functional oxygen saturation of arterial hemoglobin (SpO₂) and pulse rate. For use with neonatal, pediatric and adult patients, in hospitals, hospital-type facilities and intra-hospital transport environments. For prescription use only.
The N-395 Pulse Oximeter is designed for continuous, non-invasive monitoring of functional oxygen saturation of arterial hemoglobin (SpO2) and pulse rate by use of one of a range of compatible Nellcor Puritan Bennett oxygen transducers (sensors). The N-395 displays digital values of SpO2 and Pulse Rate. Pulse Amplitude is displayed by means of a "blip bar" presentation. The N-395 can be powered by an internal power supply operating on AC from a standard electrical utility receptacle (manually switchable From 100V to 240V) or alternatively by an integral sealed 6V rechargeable lead-acid battery. The N-395 is intended for prescription use with adult, pediatric and neonatal patients in hospitals, hospital-type facilities and intra-hospital transport environments. Audible and visual alarms for high/low saturation, pulse rate and pulse search are provided. The N-395 also includes adjustable alarm silence duration and other configurable power-on settings. The N-395 provides an audible low battery warning to alert the user of impending loss of power and consequent loss of monitoring capability. The N-395 Pulse Oximeter has visual indicators for pulse search, motion, power mode (i.e. battery or AC) and alarm silence in addition to alarm features. In addition to the above mentioned device features, the instrument has been designed to satisfy the needs of both the user and the patient. A convenient carrying handle is incorporated into the case. There is also a serial port (EIA-232 and RS-422 interface) that provides ASCII output of real-time data every two seconds. This data can be printed on serial printers. There is also an interface for nurse call systems through the rear connector. The device is also Flash ROM upgradable.
The N-395 Pulse Oximeter is designed to monitor functional oxygen saturation (SpO2) and pulse rate. The submission does not explicitly state acceptance criteria in a quantitative table format. However, it indicates reliance on "in-vitro and non-invasive controlled hypoxia studies ... to establish the N-395's accuracy and to ensure that the sensors meet their currently published accuracy specifications with the N-395."
Given the information provided, here's a breakdown of the study and its characteristics:
1. Table of Acceptance Criteria and Reported Device Performance:
| Parameter | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| SpO2 Accuracy | Meet currently published accuracy specifications of sensors. | Established by controlled hypoxia studies. |
| Pulse Rate Accuracy | Meet currently published accuracy specifications of sensors. | Established by controlled hypoxia studies. |
| Safety | Compliance with accepted industry standards; equivalent to predicates. | Demonstrated through comparison to predicate devices and testing. |
| Performance | Similar SpO2 and Pulse Rate software algorithm to predicate N-3000. | Processes information from the sensor using a similar algorithm to N-3000. |
Note: The submission refers to "currently published accuracy specifications" for the sensors but does not explicitly state what those specifications are (e.g., RMS error, bias).
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size: Not explicitly stated. The study involved "controlled hypoxia studies" which simulate different oxygen levels in human subjects.
- Data Provenance: The studies were "non-invasive controlled hypoxia studies," implying the use of human subjects under controlled conditions to induce varying oxygen saturation levels. The country of origin is not specified but is presumably where Nellcor Puritan Bennett Inc. operates or conducts its research (e.g., USA). The studies are inherently prospective as they are specifically conducted to test the device's accuracy.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications:
- Ground Truth: The "ground truth" for SpO2 in controlled hypoxia studies typically refers to arterial blood gas measurements (SaO2) taken concurrently with the pulse oximeter readings. These measurements are performed by trained medical professionals (e.g., phlebotomists, laboratory technicians).
- Number of Experts/Qualifications: The submission does not specify the number of experts or their qualifications for establishing the ground truth (SaO2). However, it is standard practice in such studies to have trained medical personnel for blood sampling and laboratory analysis, ensuring accurate SaO2 measurements.
4. Adjudication Method for the Test Set:
- Adjudication Method: Not applicable in the context of controlled hypoxia studies for pulse oximeters in the way it would be for image-based diagnostic AI. The "ground truth" (SaO2) is an objective physiological measurement, not subject to individual interpretation or consensus among experts. The pulse oximeter's reading is compared directly to this objective measurement.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
- No, an MRMC comparative effectiveness study was not done. This type of study is typically performed for diagnostic imaging devices where human readers interpret images, and the AI's effect on their performance is being evaluated. This submission is for a pulse oximeter, which provides a direct physiological measurement, not an interpretation of images by human readers in the classical sense of an MRMC study.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
- Yes, a standalone performance assessment was done. The controlled hypoxia studies are a direct evaluation of the device's (algorithm + sensor) ability to accurately measure SpO2 and pulse rate without human intervention in the measurement process itself. The device is used to generate readings, which are then compared to the ground truth.
7. The Type of Ground Truth Used:
- Type of Ground Truth: The ground truth used in controlled hypoxia studies for pulse oximeters is arterial blood gas measurements (SaO2). This is a direct, objective physiological measurement of oxygen saturation in arterial blood.
8. The Sample Size for the Training Set:
- Not Applicable / Not Provided. Pulse oximeters of this era (1999) typically relied on empirically derived algorithms and calibration curves established through extensive physiological studies, rather than "training sets" in the modern sense of supervised machine learning. While the algorithm was developed based on physiological data, the concept of a distinct, labeled "training set" as used in current AI/ML applications is not directly analogous here. The submission states the N-395 uses a "similar SpO2 and Pulse Rate software algorithm" to the predicate, N-3000, implying the core algorithm was already established.
9. How the Ground Truth for the Training Set Was Established:
- Not Applicable / Not Provided. As mentioned above, the device likely relies on a pre-existing algorithm developed from physiological principles and empirical data. The submission doesn't detail the development and "training" of this algorithm, but it would have involved similar controlled human studies where pulse oximeter readings were correlated with simultaneously obtained arterial blood gas measurements across a range of oxygen saturation levels.
§ 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).