(88 days)
The Aspect A-2000 EEG Monitor with BIS is intended for use under the direct supervision of a licensed healthcare practitioner or by personnel trained in its proper use. The BIS Monitor is intended for use on adult and pediatric patients within a hospital or medical facility providing patient care to monitor the state of the brain by data acquisition of EEG signals. The BIS may be used as an aid in monitoring the effects of certain anesthetic agents. Use of BIS monitoring to help guide anesthetic administration may be associated with the reduction of the incidence of awareness with recall in adults during general anesthesia and sedation.
The Aspect Medical Systems, Inc. A-2000 EEG BIS Monitor (hereafter referred to as the BIS Monitor) is an easy to use, microprocessor- based, 2 channel maximum EEG monitoring system. It is used to monitor the state of the brain by data acquisition of EEG. The BIS, a processed EEG variable, may be used as an aid in monitoring the effects of certain anesthetic agents.
Here's a breakdown of the acceptance criteria and study information for the A-2000™ EEG Monitor with BIS, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Criterion Description (Implied) | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Reduction of awareness with recall | Significant reduction in incidence of awareness with recall | A-2000™ EEG Monitor with BIS guided anesthesia reduced awareness by: |
- 82% (B-Aware study)
- 78% (Safe-II study)
- 78% (Kaplan study - during sedation in ICU) |
Note on Acceptance Criteria: The document does not explicitly state specific numerical acceptance criteria for the device. Instead, it relies on the results of clinical studies demonstrating a significant reduction in the incidence of awareness with recall when the BIS technology is used. The performance is presented as the achieved reduction rates in awareness.
2. Sample Sizes and Data Provenance
The provided text describes several clinical studies, not all of which were solely for the approval of this specific device, but rather for the BIS technology generally. It's important to distinguish between studies proving the device meets criteria (which are implied by the efficacy of the core BIS technology the device implements) and studies that inform the general clinical utility of BIS monitoring.
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B-Aware study (a prospective, randomized, double-blinded, multi-center study):
- Test Set Sample Size: 2503 total patients. 1227 assigned to BIS monitoring, and 1228 to routine care.
- Data Provenance: Multi-center (specific countries not mentioned, but generally implied to be within settings where such large clinical trials are conducted, likely Western countries). Prospective.
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Safe-II study (a prospective cohort study):
- Test Set Sample Size: 5057 patients with BIS monitoring compared to a historical group of 7801 patients without BIS monitoring.
- Data Provenance: Not explicitly stated, but "prospective cohort study" suggests data was collected forward in time. Historical group implies retrospective data collection for that comparison group.
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Kaplan study:
- Test Set Sample Size: Not explicitly stated, but it determined a 78% reduction in risk.
- Data Provenance: Not explicitly stated.
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AIM (Awareness Incidence and Monitoring) study (a prospective, observational, cohort, multi-center study):
- Test Set Sample Size: 19,576 patients.
- Data Provenance: 7 hospitals in the US. Prospective, observational. This study was to determine the current incidence of awareness, not directly the device's efficacy.
3. Number of Experts and Qualifications for Ground Truth Establishment (Test Set)
The document does not provide details on:
- The number of experts used to establish the ground truth for individual cases in the test sets.
- The specific qualifications of those experts (e.g., "radiologist with 10 years of experience").
The "ground truth" for the studies appears to be the occurrence or non-occurrence of awareness with recall, which is a clinical outcome typically determined by patient interview protocols and clinical assessment, not by a panel of experts reviewing individual cases in a traditional sense.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (like 2+1 or 3+1 consensus) for establishing awareness with recall in the studies. The awareness with recall is treated as a clinical outcome. For the B-Aware study, being double-blinded implies that neither the patient nor the direct caregivers/investigators assessing the outcome knew whether the patient was in the BIS or control group, which is a form of bias reduction, but not necessarily an adjudication method for individual case ground truth.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study is mentioned. The studies presented are large-scale clinical trials comparing patient outcomes (incidence of awareness) in groups with and without BIS monitoring. These are clinical effectiveness studies, not specifically multi-reader studies assessing reader performance improvement.
6. Standalone (Algorithm Only) Performance
The device is an EEG monitor that calculates a BIS (Bispectral Index) value. The effectiveness is measured by the clinical outcome (reduction in awareness) when this value is used to guide anesthetic administration by a human practitioner. Therefore, it is inherently a human-in-the-loop performance measurement. The concept of "standalone" performance (algorithm only) doesn't directly apply in the same way it would for a diagnostic image analysis algorithm. The BIS value is an algorithm output, but its utility is realized through physician interpretation and action.
7. Type of Ground Truth Used
- Clinical Outcomes/Patient Reported Outcomes: The primary ground truth for the effectiveness studies is the incidence of awareness with recall experienced by patients. This is a direct patient outcome, likely assessed through structured interviews or clinical criteria, rather than pathology, imaging, or expert consensus on a diagnostic finding.
8. Sample Size for the Training Set
The document does not provide any information regarding a training set sample size. The BIS algorithm itself was developed prior to these studies. These studies evaluate the clinical utility of the device implementing that algorithm.
9. How Ground Truth for the Training Set Was Established
The document does not provide any information on how the ground truth for the training set (if any was used for the development of the underlying BIS algorithm) was established. The focus of this 510(k) summary is on the clinical effectiveness of the complete medical device system in reducing awareness based on the output of the BIS algorithm.
§ 882.1400 Electroencephalograph.
(a)
Identification. An electroencephalograph is a device used to measure and record the electrical activity of the patient's brain obtained by placing two or more electrodes on the head.(b)
Classification. Class II (performance standards).