(214 days)
The Portapres Ambulatory Continuous Non-Invasive Blood Pressure Monitor is intended to provide the user with continuous, noninvasive blood pressure and pulse rate monitoring. The Portapres enables 24-hour continuous ambulatory measurements.
The PC-based BeatScope software used with the data from the device provides Modelflow-based computation of real-time and beat-to-beat blood pressure as well as hemodynamic parameters from the pressure waveform, including, cardiac output and total peripheral resistance.
Portapres is a portable, battery-powered device to record continuous non-invasive arterial blood pressure. Portapres is intended for 24-hour continuous recordings in ambulatory subjects. The device includes a Neoprene belt to be worn around the waist, with compartments for the Main Unit with electronics and memory card, a Pump Unit with an air pump, and a NiCd or Li battery pack. Connected to the waist belt Main Unit and Pump Unit is a Wrist Unit, used to interface with the signals from the electronics and air supply in the waist belt to the finger cuffs. The Wrist Unit then connects to a finger cuff, which consists of an inflatable air bladder and an infrared photoplethysmograph. The plethysmograph measures the finger arterial volume which varies with the patient's blood pressure. The Wrist Unit controls the pressure in the cuff bladder so as to keep the arterial volume constant at a level (the setpoint) determined during startup. The Wrist Unit contains a pressure transducer that measures the cuff pressure as an indirect measure of the patient's blood pressure. Also connected to the Wrist Unit is a hydrostatic height correction unit that compensates for the hydrostatic component of the blood pressure in the finger when this is not at heart level. This allows the patient free hand movement in ambulatory applications.
Pressure and volume signals from the finger cuffs are routed from the Wrist Unit to the Main Unit microprocessor for pump control and data acquisition purposes. The microprocessor has an internal flash memory card for storage of blood pressure wave form data.
The Main Unit is equipped with an RS232 serial interface to transfer the data stored in the flash memory card via a Control Unit to a PC and to allow remote control of the Portapres.
Here's a breakdown of the acceptance criteria and study information for the FMS Portapres Ambulatory Noninvasive Blood Pressure Monitor, based on the provided 510(k) summary:
1. Acceptance Criteria and Reported Device Performance
The provided 510(k) summary does not explicitly state specific numerical acceptance criteria for blood pressure accuracy (e.g., standard deviation, mean difference) as might be found in a more detailed validation report or a standard like ANSI/AAMI SP10.
However, the document states that the Portapres is "substantially equivalent in design (methodology) and indications for use" to predicate devices. This implies that its performance is expected to be comparable to these legally marketed devices, which would have themselves met relevant performance standards for blood pressure accuracy.
The 510(k) summary does not include a table of reported device performance metrics such as mean difference and standard deviation against a reference standard. Therefore, I cannot populate a table with specific numerical performance data directly from this document.
Missing Information: Specific numerical acceptance criteria for blood pressure measurement accuracy (e.g., AAMI/ANSI SP10 standards) and the Portapres's direct performance against those criteria are not provided in this summary. The summary focuses on substantial equivalence to predicate devices, assuming those devices met the necessary performance standards.
2. Sample Size Used for the Test Set and Data Provenance
The 510(k) summary does not provide details about a specific test set, its sample size, or data provenance (country of origin, retrospective/prospective) that directly demonstrates the device's accuracy against a gold standard.
Instead, the submission relies on the concept of substantial equivalence to predicate devices. It states: "Portapres and Finapres are substantially equivalent in design, methodology, software, manufacture, materials, intended use and principle of operation." This implies that prior testing and validation of the predicate devices (Ohmeda 2300 Finapres, Ohmeda 2350 Finapres, Task Force Monitor 3040, RODA Monitoring System) are being leveraged.
Missing Information: Direct test set sample size, country of origin, or retrospective/prospective nature of data for the Portapres itself.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Since no direct test set demonstrating the device's accuracy is described, there is no information provided regarding experts used to establish ground truth. For blood pressure monitors, ground truth is typically established by trained medical professionals using a reference standard (e.g., auscultatory method with a mercury sphygmomanometer) during a clinical validation study.
Missing Information: Number and qualifications of experts are not mentioned as no direct study for the Portapres's accuracy is detailed.
4. Adjudication Method for the Test Set
As no specific test set or study validating the Portapres's accuracy is described, no adjudication method is mentioned.
Missing Information: Adjudication method is not provided.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
The summary does not mention a multi-reader multi-case (MRMC) comparative effectiveness study. This type of study is more common for diagnostic imaging devices where human interpretation is a key component. Blood pressure monitors are primarily direct measurement devices, and their validation focuses on agreement with reference standards, not on improvement in human reader performance.
Missing Information: No MRMC study was conducted or reported.
6. Standalone Performance Study
The 510(k) summary does not explicitly describe a standalone performance study (i.e., algorithm only without human-in-the-loop performance) for the Portapres.
The claim of substantial equivalence implies that the device's performance, by virtue of its "design, methodology, software," is comparable to its predicates, which would have undergone their own standalone validation. The Portapres itself is a device that generates data (blood pressure waveform and derived parameters), and its standalone performance would be its accuracy in doing so compared to a reference standard. The summary does not provide direct evidence of this for the Portapres specifically.
Missing Information: A specific standalone performance study report for the Portapres is not detailed in this summary.
7. Type of Ground Truth Used
Given that no direct study for the Portapres's accuracy is detailed, the specific type of ground truth used to validate the Portapres cannot be explicitly stated from this document.
However, for non-invasive blood pressure monitors, the gold standard (ground truth) for validation typically involves:
- Auscultatory method: Manual blood pressure measurement performed by trained observers using a stethoscope and sphygmomanometer, often with double or triple auscultation and averaging.
- Intra-arterial catheterization: Invasive measurement, used less commonly for routine non-invasive device validation but considered highly accurate.
The summary's reliance on substantial equivalence suggests that the predicate devices were validated against such ground truths.
Missing Information: The specific type of ground truth used for the Portapres's validation is not detailed.
8. Sample Size for the Training Set
The 510(k) summary does not provide information about a training set or its sample size. The device described, the Portapres, is a measurement device that employs algorithms for continuous blood pressure estimation and hemodynamic parameter calculation (like Modelflow for cardiac output). While such algorithms might be "trained" or developed using data, this summary does not provide details of that process or associated sample sizes.
Missing Information: Training set sample size is not provided.
9. How the Ground Truth for the Training Set Was Established
As no training set is described, information on how its ground truth was established is not provided. The algorithms (e.g., Modelflow) would have been developed and validated using physiological data over many years, but these details are not part of this 510(k) submission for the device itself.
Missing Information: Ground truth establishment for a training set is not provided.
Summary of Limitations of the Provided Document:
This 510(k) summary primarily focuses on establishing "substantial equivalence" to existing predicate devices. It does not contain a detailed report of a new clinical validation study for the Portapres itself, which would typically include explicit acceptance criteria, sample sizes, methodology for ground truth establishment, and reported performance metrics. The FDA's acceptance in this case is based on the argument that the new device's design, methodology, and intended use are similar enough to previously cleared devices that it can be presumed to be safe and effective without requiring a full, new, independent clinical validation study report within the summary document.
§ 870.1130 Noninvasive blood pressure measurement system.
(a)
Identification. A noninvasive blood pressure measurement system is a device that provides a signal from which systolic, diastolic, mean, or any combination of the three pressures can be derived through the use of tranducers placed on the surface of the body.(b)
Classification. Class II (performance standards).