REDOX by KINETIC CONCEPTS, INC. | FDA 510(k) Summary

AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview

Intended Use

The REDOX pump is indicated for patients who would benefit from a pneumatic compression device applied to the arm. Such benefits include helping to:

Prevent Deep Venous Thrombosis (DVT) .
Prevent venous stasis in the upper extremities .
. Enhance arterial circulation in the upper extremities
Reduce post-operative pain and swelling in the upper extremities. ●
Reduce edema in the upper extremities. .
. Reduce wound healing time in the upper extremities
Treat and assist healing of cutaneous ulceration in the upper extremities. .
Reduce compartmental pressures in the upper extremities. .
Reduce the need for anticoagulant medications prescribed for the prevention of DVT. .

Device Description

The REDOX functions as an intermittent pneumatic compression device that aids in the circulation of blood in patients with lymphedema due to mastectomy, surgery, injury or disease. The REDOX is not a life-supporting or life-sustaining device. Also, the REDOX is not an implant (short-term or long-term), nor is it a sterile device. The REDOX is an electrically-operated (see electrical testing in test section), softwaredriven (see software testing in test section), prescription device (see drawing A-205360 in labeling section), which is used in a hospital environment (see mechanical testing in test section). The REDOX is comprised of two major components -- the reusable pump unit (controller device) (see drawings C-205303, D-212032, D-212032, D-235308 in engineering drawings section) and a single-patient use inflatable wrap (see drawings D-410009, D-410008, in engineering drawings section). Neither component contains a drug nor biological product as a subcomponent.

The REDOX unit uses a 16' hospital grade power cord (see drawing B-205337 in engineering drawings section) to supply a voltage of 115 VAC at a frequency of 60Hz with a maximum current consumption of 0.33 amperes and a maximum electrical leakage of less than 100 microamps (see electrical testing in test section) from its power source. An exterior shell made of ABS material, measuring 12" long by 10 3/4" wide by 7" deep, protects the subcomponents of the REDOX 11 pound unit (see drawings D-205306, D-212032 in engineering drawings section).

The compressor inflates one or more of the wraps in minimum intervals of 10 seconds at a maximum pressure of not more than 180 mmHg (±15 mmHg).

The unit features a microprocessor (see drawing D-210528 in engineering drawings section) that controls the unit's operation. The user selects: 1) the pressure from 140 to 180 mmHg, in 10 mmHg increments; 2) the cycle time from 20 to 60 seconds, in 10 second increments, and; 3) the hold time from 1 to 5 seconds. in 1 second increments (see software testing in test section). Selections are made by the user interfacing with the membrane switch located on the front of the unit (see drawing C-205315 in engineering drawings section and drawing B-235309 in labeling section). The microprocessor also has detection capabilities to monitor the pressure in the wrap(s), adjusting the in and out flow of air on every cycle, to ensure that the target pressure is consistently maintained. If for any reason the target pressure cannot be maintained, the microprocessor alarm capabilities will activate both visual and audio alarms (see software testing in test section). These alarm capabilities are built in to detect high pressure, low pressure and/or unit malfunction situations, should they ever occur (see software testing in test section).

The non-sterile inflatable wraps are for single patient use only (see labeling section). Arm wraps (see drawings D-410009, D-410008, in engineering drawings section) are designed to fit around and compress the veins in the arm, including both collateral veins and deep veins. Hook-and-loop fasteners are used to hold the wrap comfortably around the arm. The wraps are RF-welded to create an air chamber that can then be inflated by the REDOX unit. This air chamber is what actually applies pressure against the body.

AI/ML Overview

The provided document describes the REDOX pneumatic compression device and its 소프트웨어 (software) testing. It includes acceptance criteria for the software's performance, details about the testing methodology, and the results obtained.

Here's an analysis of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance and Results
Maintain average pressure within ±15 mmHg of target (pulsation verification)	Pulsation Verification Procedures:

Tested for various pressure settings (140, 160, 180 mmHg), cycle times (20 sec), hold times (1-5 sec) for foot and arm wraps (right, left, and bilateral).
Each setting was tested for 5 consecutive cycles after "ramp-up."
Results: The tables on pages 10-12 show the recorded pressure readings for all tested configurations. For example, at PS 1 (140 mmHg), CT 20, HT 1, the average pressures for the foot wrap (right, left, bilateral) ranged from 131.2 to 143.2 mmHg, and for the arm wrap (right, left, bilateral) ranged from 140.8 to 152 mmHg. All these reported average pressures fall within ±15 mmHg of the target 140 mmHg (i.e., between 125 mmHg and 155 mmHg). Similar checks for PS 3 (160 mmHg target, range 145-175 mmHg) and PS 5 (180 mmHg target, range 165-195 mmHg) show that the reported average pressures generally fall within the specified tolerance. |
| Activate visual and audio alarms for high pressure | Alarm Testing - High Pressure:
Method: Kinked PVC hose from unit to inflatable wrap.
Results: The table on page 13 indicates "X" for "YES" under "HIGH PRESSURE" for all foot wrap and arm wrap configurations (right, left, bilateral), and for "UNIT MALFUNCTION" scenarios where the hose was removed. This implies the unit successfully alarmed under high-pressure conditions. |
| Activate visual and audio alarms for low pressure | Alarm Testing - Low Pressure:
Method: Cut an 1/8" slit in the bladder area of the wrap, replaced a good wrap with the cut wrap, and observed if the unit alarmed after 5 consecutive cycles.
Results: The table on page 13 indicates "X" for "YES" under "LOW PRESSURE" for all foot wrap and arm wrap configurations (right, left, bilateral). This implies the unit successfully alarmed under low-pressure conditions. |
| Activate visual and audio alarms for unit malfunction | Alarm Testing - Unit Malfunction:
Method: Disconnected PVC hose from the unit.
Results: The table on page 13 indicates "X" for "YES" under "LOW PRESSURE" for unit malfunction scenarios (Right Hose Removed, Left Hose Removed, Both Hoses Removed), and also "X" for "YES" under "HIGH PRESSURE" for these scenarios. This suggests that the unit alarms (likely a low-pressure alarm due to hose removal resulting in no pressure or unexpected high pressure due to blocked outflow) correctly for unit malfunction. The text explicitly states "If the unit alarms then the software passes." |
| Software handles rapid input changes (stress test) | Software Stress Test - Rapid Input:
Method: Rapidly change pulsation setting after the unit has "ramped-up."
Results: The table on page 13 indicates "X" for "PASS" under "RAPID INPUT" for all foot wrap and arm wrap configurations. This means the unit adjusted to the new pulsation setting correctly. |
| Software handles operational disruptions (stress test) | Software Stress Test - Operational Disrupt:
Method: Change pulsation setting while a wrap is inflated.
Results: The table on page 13 indicates "X" for "PASS" under "OPERATIONAL DISRUPT" for all foot wrap and arm wrap configurations. This means the unit operated at the new pulsation setting on the next cycle, indicating successful handling of the disruption. |

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: For pulsation verification, each unique combination of pressure setting (3 levels), hold time (5 levels), and wrap configuration (right foot, left foot, bilateral foot, right arm, left arm, bilateral arm) was tested for 5 consecutive cycles after ramp-up. This amounts to (3 * 5 * 6) = 90 distinct test scenarios, each with 5 data points, or 450 individual pressure readings.
For alarm testing and software stress tests, specific scenarios were performed for each wrap configuration, covering various types of alarm conditions and stress inputs. The exact number of individual successful alarms or operational adjustments is not quantified beyond a 'PASS' mark.
Data Provenance: The data is prospective and generated from internal testing of the device, Unit 61578. The country of origin is not explicitly stated but can be inferred as the United States given the submission to the FDA.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

Ground truth for this device, a pneumatic compression device, is established by engineering specifications and measurements. The "ground truth" is whether the device accurately maintains pressure, alarms when necessary, and responds correctly to user inputs, as defined by its design specifications.
There were no human experts (like radiologists) used to establish ground truth for this device's software performance, as it's a mechanical/software functional test rather than an interpretive medical imaging test. The testing was performed by "T. Randolph" (likely a test engineer or technician) on Unit 61578.

4. Adjudication Method for the Test Set

None applicable in the typical sense of expert review for diagnostic devices. The acceptance criteria are objective and quantitative (e.g., pressure within ±15 mmHg) or binary (alarm/no alarm, pass/fail for stress tests). The testing procedures directly assess these objective criteria.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This type of study is typically used for diagnostic devices where human readers interpret medical images or data. The REDOX device is a therapeutic pneumatic compression device, and its safety and effectiveness were evaluated through engineering and software functional testing rather than human interpretation tasks.

6. Standalone Performance Study (i.e., algorithm only without human-in-the-loop performance)

Yes, a standalone performance study was done for the algorithm (software). The entire non-clinical testing described, including pulsation verification, alarm testing, and software stress tests, assesses the device's software and hardware functionalities without human intervention in its operational performance. The results table specifically details the pressure outputs and alarm triggers, demonstrating the algorithm's performance.

7. Type of Ground Truth Used

The ground truth used is based on engineering specifications and measurable physical parameters.
- For pulsation verification: The specified target pressure (e.g., 140 mmHg, 160 mmHg, 180 mmHg) and the ±15 mmHg tolerance range.
- For alarm testing: The expected activation of visual and audio alarms under defined low pressure, high pressure, and unit malfunction conditions.
- For software stress tests: The expected correct adjustment to new settings after rapid input or operational disruptions.

8. Sample Size for the Training Set

The document does not provide details about a training set for the device's software. Given the release date of 1996 and the nature of the device (pneumatic compression), it is highly probable that the software development did not involve what would today be commonly referred to as a "training set" in the context of machine learning. The software likely followed traditional deterministic programming paradigms and was developed based on established control theory and engineering principles.

9. How the Ground Truth for the Training Set Was Established

As there's no mention of a "training set" in the context of machine learning, this question is not applicable. The ground truth for the software's functionality was established through engineering design specifications and requirements.