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NuStat is indicated for temporary control of internal organ space bleeding for patients displaying class III or class IV bleeding. It may also be used for control of severely bleeding wounds such as surgical wounds and traumatic injuries.

The NuStat is a hemostatic wound dressing that is composed of continuous filament silica and bamboo cellulose rayon fiber and is provided with radiopaque thread. The distribution of cellulose and silica fibers in each dressing is 65% silica fiber and 35% bamboo cellulose rayon fiber. The dressings are available in various sizes and provided sterile in either foil, Tyvek, or LDPE pouched configurations. The NuStat hemostatic wound dressings have a number of hemostatic properties that enhance the ability of the dressing to temporarily control bleeding. NuStat Hemostatic Dressing's mode of action is via absorption of fluid, which results in a physical aggregation of blood cells and clotting factors at the site of application. The radiopaque element allows for detection via x-ray.

The document describes a 510(k) premarket notification for a medical device called NuStat®, a non-absorbable, hemostatic gauze for temporary internal use. The submission seeks to expand the prescription (Rx) indication for use for the device. The study proves the device's substantial equivalence to a legally marketed predicate device (Z-Medica, LLC's D2 Dressing, DEN160012) and its identity to a reference device (Beeken Biomedical, LLC's NuStat XR, K160578).

Here's a breakdown of the requested information based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not present specific quantitative acceptance criteria or pass/fail thresholds for each test, but rather describes the performance evaluated against the "special controls for the non-absorbable, hemostatic gauze for temporary internal use as identified in 21 CFR 878.4454" and substantial equivalence to the predicate/reference devices. Therefore, the "acceptance criteria" are implied by the successful testing results and determination of substantial equivalence.

2. Sample Sizes and Data Provenance

• Sample Size for Test Set (Pre-market Studies):

  • Pilot Study: "Pilot study to Develop and Refine a Survival Mode of Severe Hemorrhage for the Evaluation of the NuStat Internal Hemostatic Dressing (NuStat XR)" - ANS 2319 (number of animals not specified)
  • Pivotal GLP Study: "Evaluation of the NuStat Trauma Pad XR Dressing When Applied to a Linear Resection Defect, 48 Hours and 28 Day"- FP-SS (number of animals not specified, but GLP implies rigorous standards)
  • Biocompatibility/Toxicity Tests: Various ISO 10993 tests (number of animals or in vitro samples not specified, but these are standardized tests).
  • In-vitro Clot Assessment: (number of bench tests not specified).
  • Particulate Release Testing: (number of tests not specified).
  • Swell Percent/Tensile/Tear Strength/Stability: (number of tests not specified).

• Data Provenance:

  • The animal studies (Pilot and Pivotal GLP studies) were conducted using a pig model of liver resection.
  • Other tests include standardized ISO 10993 biocompatibility and toxicity tests (e.g., mice for acute systemic toxicity, rabbits for pyrogenicity and sub-acute systemic toxicity/implantation).
  • The studies were prospective for the purpose of demonstrating safety and effectiveness for a 510(k) submission.
  • The country of origin is not explicitly stated, but as a US FDA submission, it's typically expected that these studies conform to international good laboratory practices (GLP) and are conducted in reputable facilities, often in the US or internationally accepted sites.

3. Number of Experts and Qualifications for Ground Truth

The document does not mention the use of human experts to establish ground truth in the context of device performance, as this device (hemostatic gauze) is assessed directly through in-vivo (animal model) and in-vitro laboratory testing for its physical and biological performance characteristics. The "ground truth" is established by direct measurement and observation of the device's hemostatic capabilities, radiographic visibility, biological interactions, and physical properties in these controlled experimental settings.

4. Adjudication Method for the Test Set

Adjudication methods (like 2+1, 3+1) are typically used in clinical studies involving interpretation of medical images or patient outcomes, often by multiple human readers or experts, to resolve discrepancies and establish a consensus ground truth. This is not applicable here as the device's performance is determined by direct physiological and material science measurements in animal models and laboratory settings, rather than subjective human assessment of ground truth.

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

No, an MRMC comparative effectiveness study was not conducted. This type of study is specifically designed for diagnostic devices, particularly those involving medical imaging where human interpretation of AI outputs is a key component. NuStat is a therapeutic hemostatic device, not a diagnostic AI system.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

Not applicable. NuStat is a physical medical device (hemostatic gauze), not an algorithm or AI system. Its performance is inherent to its physical properties and biological interactions, not a computational output that would require a "standalone" algorithmic evaluation.

7. Type of Ground Truth Used

The "ground truth" for evaluating NuStat's performance was established through:

• Direct Physiological Measurement/Observation (in-vivo): In the pig model studies, the ability of the device to achieve hemostasis within a specific time (3 minutes), the absence of vascular obstruction/embolization, and the lack of infection were directly observed and measured. Radiographic visibility was visually assessed.
• Pathology/Histology: Likely used in the pivotal GLP study and local effects after implantation study to assess inflammation, adhesions, local toxicity, and the presence or absence of issues like vascular obstruction or embolization. The document mentions "assessments customized to the intended use" in the pivotal GLP study.
• Standardized Laboratory Testing (in-vitro): For biocompatibility, cytotoxicity, sensitization, irritation, systemic toxicity, pyrogenicity, endotoxin, interaction with blood, genotoxicity, in-vitro clot assessment, particulate release, swell percent, tensile strength, tear strength, and stability, the ground truth was established by adherence to recognized international standards (ISO, USP) and the measured outcomes of these tests.

8. Sample Size for the Training Set

Not applicable. NuStat is a physical medical device, not a machine learning model, so there is no "training set" in the context of AI development. The "training" for this device would refer to the research and development phases where the material composition and design were optimized.

9. How Ground Truth for the Training Set Was Established

Not applicable, as explained in point 8.

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OTC: NuStat is indicated to temporarily control bleeding in minor cuts, lacerations, punctures, abrasions and incisions.
Rx: NuStat is a single-use hemostatic wound dressing applied externally with mechanical compression to temporarily control bleeding in lacerations, punctures, abrasions, surgical wounds (operative, dermatological, etc.) and traumatic injuries.

The Nustat XR Hemostatic Dressing is a hemostatic wound dressing that composed of continuous filament silica and bamboo cellulose. The distribution of cellulose and silica fibers in each dressing is 65% silica fiber, 35% cellulose.
The dressings are available in various sizes in either Tyvek or LDPE pouched configurations and are available with or without the Radiopaque thread.
The dressings are either z-folded or rolled into a medical grade Tyvek pouch or LDPE pouch which is then sterilized using gamma irradiation to a sterility assurance level of 10-6.
The NuStat® range of hemostatic wound dressings have a number of hemostatic properties which enhance the ability of the dressing to temporarily control bleeding. The cellulose and continuous filament silica influence the contact activation pathway of the coagulation cascade by absorbing blood fluids, resulting in the localized concentration of platelets and clotting factors. The negatively charged fibers of the continuous filament silica simulate the negative ions secreted by activated platelets, which further influence the coagulation cascade. The radiopaque element allows for detection via x-ray.

The provided text describes the Nustat XR Hemostatic Dressing and its substantial equivalence to predicate devices, but does not explicitly state specific acceptance criteria or a dedicated study proving the device meets those criteria in a quantitative manner.

Instead, the performance testing section details various tests conducted to demonstrate substantial equivalence to predicate devices. This means the device is considered safe and effective because it performs as well as or similarly to a device already legally marketed.

However, based on the provided text, I can extract and infer information to address your request as much as possible:

1. Table of Acceptance Criteria and Reported Device Performance

Since explicit acceptance criteria are not provided, I will construct a table based on the performance tests described, indicating what was evaluated and the general outcome (which is "passing" or "substantially equivalent" in relation to predicate devices).

• Immediate hemostasis upon release of manual pressure (T0)
• Hemostasis at 60 minutes
• Re-bleeding during the 60-minute observation period |
  | Product Stability/Integrity | Age-Testing (Packaging integrity per ASTM F2096) | Package remained intact after accelerated aging conditions. |
  | | Age-Testing (aPTT on aged product) | Demonstrated that the product was functioning and was substantially equivalent to the predicate device after accelerated aging. |
  | Radiopacity | Imaging analysis for radiopaque thread | Met the requirements of ASTM F640-07. |

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

• Biocompatibility Testing: The text does not specify sample sizes (e.g., number of cells for cytotoxicity, number of animals for sensitization/irritation).
• Laboratory Verification Testing (aPTT): The text does not specify the number of samples tested for aPTT.
• Animal Testing (Swine femoral model): 15 swine were used. The data provenance is a "complex penetrating femoral artery groin injury" model, which is a common experimental model for hemostatic devices. The country of origin for the study is not specified but is presumably where the company is based or where the contract research organization operates. This is a prospective study since devices were randomized and assigned to animals and observed for specific endpoints.
• Age-Testing & Radiopacity: Sample sizes are not specified.

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

There is no information provided about experts establishing "ground truth" in the classical sense for this type of submission.

• For biocompatibility and laboratory verification, the "ground truth" is typically defined by established laboratory standards and predicate device performance.
• For the animal study, the "ground truth" for endpoints like hemostasis and re-bleeding would be directly observed by the study personnel (e.g., veterinarians, researchers) involved in the experiment. Their qualifications are not explicitly mentioned but would be assumed to be appropriate for conducting animal studies and assessing physiological responses.

4. Adjudication Method for the Test Set

No adjudication method (e.g., 2+1, 3+1, none) is mentioned or implied for any of the performance tests. The animal study results would likely be determined by direct observation and measurement by the study team.

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 done. This type of study is typically relevant for interpretative devices, especially those involving AI for image analysis, where human readers interpret results. The Nustat XR is a physical hemostatic dressing, so MRMC studies involving AI assistance are not applicable.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done

No, a standalone algorithm-only performance study was not done. This concept is relevant for AI-powered diagnostic or interpretive algorithms. The Nustat XR is a physical medical device.

7. The Type of Ground Truth Used

• Biocompatibility: Established ISO standards and laboratory methods define successful outcomes.
• Laboratory Verification (aPTT): Comparison against the performance of legally marketed predicate devices serves as the "ground truth" for substantial equivalence.
• Animal Testing: Direct physiological observation (immediate hemostasis, hemostasis at 60 minutes, re-bleeding) in the swine model serves as the ground truth.
• Age-Testing: ASTM F2096 standards for packaging integrity and comparison to predicate device aPTT for product function.
• Radiopacity: ASTM F640-07 requirements for radiopaque elements.

Essentially, the "ground truth" for this device's performance demonstration is based on established scientific methods, biological responses in a live animal model, engineering standards, and direct comparison to predicate devices, rather than human expert consensus on interpretations of data.

8. The Sample Size for the Training Set

There is no mention of a "training set" as this device is not an AI/machine learning algorithm. The closest equivalent would be the data generated during the product development and manufacturing process, but this is not organized as a "training set" in the context of AI.

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

Not applicable, as there is no "training set" for this type of medical device.

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NuStat is indicated to temporarily control bleeding in minor cuts, lacerations, punctures, abrasions and incisions.

NuStat XR is a single-use hemostatic wound dressing applied externally with mechanical compression to temporarily control bleeding in lacerations, punctures, abrasions and incisions.

The NuStat® range of hemostatic wound dressings are textiles composed of continuous filament silica and bamboo cellulose. This submission adds a radiopaque filament to the NuStat XR models of the legally marketed dressing. The dressings are produced in various sizes to accommodate different wound sizes, ranging from a width of 2" to 8" and length of 2" to 60". The dressings are either z-folded or rolled into a medical grade Tyvek pouch which is then sterilized using gamma irradiation to a SAL of 10-6. The NuStat® range of hemostatic wound dressings have a number of hemostatic properties which enhance the ability of the dressing to temporarily control bleeding. The cellulose and continuous filament silica influence the contact activation pathway of the coagulation cascade by absorbing blood fluids, resulting in the localized concentration of platelets and clotting factors. The negatively charged fibers of the continuous filament silica simulate the negative ions secreted by activated platelets, which further influence the coagulation cascade. The radiopaque element allows for detection via x-ray.

The provided text describes the NuStat® Hemostatic Dressing, an unclassified medical device. While it mentions performance data, this primarily pertains to biocompatibility, sterility, and radiopacity, and does not include a study proving the device meets acceptance criteria related to its primary function of controlling bleeding. The document explicitly states that efficacy testing was not required for this submission.

Therefore, many of the requested sections about acceptance criteria and a study proving device performance in that context cannot be directly extracted from the provided text. However, I can provide information based on what is available:

1. A table of acceptance criteria and the reported device performance

2. Sample size used for the test set and the data provenance

The document does not provide specific sample sizes for the biocompatibility, sterility, or radiopacity tests. It implies these were standard tests performed according to recognized international standards. Data provenance is not specified, but these are likely laboratory tests conducted for regulatory submission.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

This information is not provided in the document. The tests described (biocompatibility, sterility, radiopacity) are typically performed in a laboratory setting by qualified technicians following established protocols, rather than requiring expert consensus on a ground truth in the way a diagnostic AI model might.

4. Adjudication method for the test set

Not applicable for the types of tests described (biocompatibility, sterility, radiopacity). These are objective measurements against defined standards.

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. An MRMC study is not mentioned. This device is a hemostatic dressing, not an AI-assisted diagnostic tool.

6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done

Not applicable. This is a physical hemostatic dressing, not an algorithm or AI product.

7. The type of ground truth used

For the biocompatibility, sterility, and radiopacity tests, the "ground truth" would be the established scientific and regulatory standards/benchmarks as defined by ISO and ASTM, against which the device's performance was measured. For example, for sterility, the ground truth is a 10⁻⁶ SAL.

8. The sample size for the training set

Not applicable. This is a physical medical device, not an AI model requiring a training set.

9. How the ground truth for the training set was established

Not applicable. This is a physical medical device.

Key Clarification from the Document Regarding Efficacy:

The document explicitly states: "In vivo and in vitro testing to evaluate the efficacy of the NuStat® range of dressings was not required as the addition of a radiopaque element does not affect the performance of the device as a hemostatic wound dressing." This indicates that for this specific 510(k) submission (K142363), the efficacy of the hemostatic function was considered established through the predicate device (Stasilon FR K072890), and the new submission focused on the safety aspects related to the radiopaque element and general device properties. Therefore, the document does not contain a study "proving the device meets acceptance criteria" for its primary hemostatic function.

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