(61 days)
The Abdominal Aortic Tourniquet is indicated for use in the battlefield to control difficult bleeds in the inguinal area.
The Abdominal Aortic Tourniquet is a wedge shaped bladder that when inflated pushes in on the lower abdomen compressing all the structures within to include the descending aorta. The Abdominal Aortic Tourniquet (AAT) is designed to be used by military medical personnel in the battlefield to control bleeding in the inguinal area where standard tourniquets cannot be used. The device may be used instead of "mechanical pressure", allowing the medic to attend to other injuries or soldiers. The Abdominal Aortic Tourniquet is used to control a difficult bleed for up to 60 minutes until the injured soldier can be transferred to evacuation personnel for further treatment.
The Abdominal Aortic Tourniquet (AAT) is a medical device designed to control difficult bleeds in the inguinal area, primarily for military medical personnel in battlefield settings. The provided text describes the safety and performance studies conducted to demonstrate its substantial equivalence to predicate devices.
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for the AAT are implied through the comparison with predicate devices and the outcome of the performance testing. While specific numerical acceptance criteria (e.g., "must achieve X% reduction in blood flow") are not explicitly stated, the studies aimed to show that the AAT could significantly decrease or halt blood flow without causing significant damage or discomfort beyond what is manageable.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Mechanical Efficacy in Reducing/Halting Blood Flow | Animal Study (Swine): Flow was essentially undetectable in the femoral catheter during tourniquet application for 60 minutes. |
| Human Study: Average pressure required to cease flow in the common femoral artery (CFA) was 191mmHg (min 150mmHg, max 230mmHg). | |
| Safety - Prevent Significant Tissue Damage | Animal Study (Swine): Serum potassium and lactate did not reach clinically significant numbers. Gross and histological examination revealed no signs of significant ischemia or necrosis of the small and large intestine after 60 minutes of application. |
| Safety - Manageable Discomfort | Human Study: Average discomfort at cessation of flow was 6.6 on a 1-10 pain scale (min 4, max 10). All discomfort ceased when the device was released. |
| Duration of Efficacy | Animal Study (Swine): Evaluated for 60 minutes of application. The device is designed for use up to 60 minutes. |
| Substantial Equivalence to Predicate Devices | The Abdominal Aortic Tourniquet was determined to be substantially equivalent to the predicate devices (Combat Ready Clamp, A.T.S. Automatic Pneumatic Tourniquet System) in decreasing or eliminating blood flow, and in its safety and performance profile (non-inferior to predicate devices in these aspects). |
2. Sample Size Used for the Test Set and the Data Provenance
- Animal Study: Eight (8) swine animals. The provenance is not explicitly stated but is implicitly a laboratory or research animal facility. The study design appears prospective.
- Human Study: Nine (9) subjects. The provenance is not explicitly stated regarding country, but it is a prospective study as it involved active measurements during device application.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
The text does not mention the use of external experts for establishing ground truth for the test sets in the typical sense of expert consensus for diagnostic accuracy.
- In the animal study, "ground truth" for blood flow cessation was established through objective measurements (femoral catheter flow, mean arterial pressure, central venous pressure, intra-abdominal pressure, potassium levels, lactate levels) and gross/histological examination performed by potentially veterinary pathologists or researchers. The number and qualifications of these individuals are not specified.
- In the human study, "ground truth" for blood flow cessation was established using Pulsed-wave Doppler to measure flow in the common femoral artery. Discomfort was self-reported by subjects using the verbal 1-10 pain scale. The personnel conducting the Doppler measurements and recording discomfort would be trained researchers or clinicians, but their specific qualifications and number are not detailed.
4. Adjudication Method for the Test Set
There was no indication of an adjudication method (like 2+1 or 3+1) used for interpreting results in either the animal or human study. The measurements (Doppler flow, pressure, pain scale, lab results, histology) are objective or self-reported outcomes that generally do not require adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs Without AI Assistance
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not performed. The device is an Abdominal Aortic Tourniquet, a physical medical device, not an AI-powered diagnostic or assistive tool for human readers. Therefore, the concept of improving human readers with AI assistance is not applicable to this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, in a way, the studies performed represent the "standalone" performance of the device (tourniquet-only performance). The animal and human studies assessed the device's ability to mechanically stop blood flow and its associated effects, independent of human interpretive input. Human interaction was limited to application and monitoring.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
- Animal Study: The ground truth for efficacy (blood flow reduction/cessation) was based on direct physiological measurements (femoral catheter flow) and safety (tissue damage) was based on objective laboratory markers (potassium, lactate) and pathology (gross and histological examination of tissues).
- Human Study: The ground truth for efficacy (blood flow reduction/cessation) was based on objective imaging data (Pulsed-wave Doppler measurements of CFA flow). The ground truth for discomfort was self-reported outcomes data (verbal 1-10 pain scale).
8. The Sample Size for the Training Set
No training set is mentioned as this is a physical medical device and not an AI/algorithm-based device requiring machine learning training. The studies described are performance and safety validation studies.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there was no training set for an AI/algorithm.
§ 870.4450 Vascular clamp.
(a)
Identification. A vascular clamp is a surgical instrument used to occlude a blood vessel temporarily.(b)
Classification. Class II (performance standards).