(27 days)
The THERMOGARD can be used with any of the Alsius Catheters. The indications for use are specific to the catheter. Please refer to the Indications for Use statement in the catheter specific Instructions for Use.
The THERMOGARD/Alsius Catheter Thermal Regulation System, using either the Icy™ or Fortius™ model catheter, is indicated for use:
- In cardiac surgery patients to achieve and or maintain normothermia during surgery and recovery/intensive care, and
- To induce, maintain and reverse mild hypothermia in neurosurgery patients in surgery and recovery/intensive care.
The Alsius THERMOGARD™ and Cool Line™ Catheter Thermal Regulation System is indicated for use in fever reduction, as an adjunct to other antipyretic therapy, in patients with cerebral infarction and intracerebral hemorrhage who require access to the central venous circulation and who are intubated and sedated.
The THERMOGARD and Catheter Thermal Regulation System consists of the THERMOGARD, a disposable Start Up Kit used to interface between the cooling bath of the THERMOGARD and the intravascular Catheter. The THERMOGARD is an integrated electro-mechanical heater/cooler that consists of a temperature monitor, a temperature controller unit, a heat exchanger unit, and roller pump. It supplies temperature controlled sterile saline to the indwelling Catheter that is placed percutaneously in the patient.
The technical characteristics of the Catheter are identical to the predicate device with the exception of revisions to the software that controls the device.
All models of Alsius Intravascular catheters are available for use with the THERMOGARD.
The provided text describes a 510(k) summary for the ALSIUS CORPORATION'S THERMOGARD and Catheter Thermal Regulation System. This document focuses on demonstrating substantial equivalence to a predicate device rather than presenting acceptance criteria and a study proving a device meets those criteria for a novel technology.
However, the document does contain information about a clinical trial related to the device's use in fever reduction and outlines certain limitations on its use based on the trial results. This information can be re-purposed to infer a type of "acceptance criteria" based on the observed safety and effectiveness, and the study details are provided.
Here's an analysis based on the information available:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" in the typical sense for a new device's performance metrics (e.g., sensitivity, specificity, accuracy thresholds). Instead, it presents mortality rates from a clinical trial that led to a warning and limitation on the device's indications for use.
The "acceptance criteria" here are effectively inferred limits on where the device's performance was considered safe and effective enough for its intended use, particularly for fever reduction, based on its performance relative to a control group. For the conditions where the device was not shown to be safe and effective, the mortality rates in the Cool Line group were not significantly better (and in some cases numerically worse) than the control group.
| Acceptance Criteria (Inferred from FDA Warning) | Reported Device Performance (Mortality % with Cool Line System) | Control Group Performance (Mortality % without Cool Line System) | p-value | Indication/Patient Cohort |
|---|---|---|---|---|
| Acceptable for Fever Reduction: Device demonstrated safety and effectiveness as an adjunct to other antipyretic therapy. (Implies non-inferiority or better outcomes compared to control, though not explicitly stated as a statistical threshold for improvement.) | CI: 18.8% (n=3/N=16) | CI: 21.4% (n=3/N=14) | 0.74 | Cerebral Infarction (CI) |
| ICH: 24.2% (n=8/N=33) | ICH: 25.9% (n=7/N=27) | 1.00 | Intracerebral Hemorrhage (ICH) | |
| NOT Acceptable for Fever Reduction: Safety and effectiveness not demonstrated in these populations, leading to a warning. (Implies outcomes were not sufficiently better or were worse than control, or demonstrated a safety concern.) | PTBI: 22.7% (n=10/N=44) | PTBI: 10.5% (n=4/N=38) | 0.24 | Primary Traumatic Brain Injury (PTBI) |
| SAH: 21.3% (n=13/N=61) | SAH: 11.1% (n=7/N=63) | 0.15 | Subarachnoid Hemorrhage (SAH) |
Note: The p-values indicate a lack of statistically significant difference between the Cool Line and Control groups in mortality for all cohorts in this specific trial. However, for PTBI and SAH, the Cool Line group numerically had higher mortality, which contributed to the FDA's warning about lack of demonstrated safety and effectiveness for those indications for fever reduction.
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: A randomized controlled trial of 296 patients was conducted.
- Cool Line group: (16 CI + 33 ICH + 44 PTBI + 61 SAH) = 154 patients
- Control group: (14 CI + 27 ICH + 38 PTBI + 63 SAH) = 142 patients
- Data Provenance: The document does not explicitly state the country of origin. It is a prospective randomized controlled trial.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
This type of information is generally not applicable to a clinical trial involving patient outcomes like mortality. The "ground truth" here is the actual patient outcome (mortality), which is a definitive clinical event, not an expert interpretation of an image or a condition. Therefore, no experts were "establishing ground truth" in that sense.
4. Adjudication Method for the Test Set
Not applicable in the context of a clinical trial where the primary endpoint is mortality. Mortality is typically recorded as a factual event, not subject to adjudication in the same way, for example, an imaging diagnosis or a pathological finding might be.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, this was not an MRMC study. An MRMC study typically involves multiple human readers interpreting cases (e.g., medical images) to assess diagnostic performance, often with and without AI assistance, and then analyzing the variability and agreement among readers. This study was a randomized controlled trial comparing a medical device with an active control group based on patient survival outcomes.
- Effect size of human readers improvement with AI vs without AI assistance: Not applicable, as this was not an imaging diagnostic study involving human readers and AI assistance.
6. Standalone (i.e., algorithm only without human-in-the-loop performance) Study
- No, this was a study of a medical device (THERMOGARD Thermal Regulation System) used in patients, with human medical staff operating and managing the system. It is not an algorithm designed for diagnostic or predictive tasks that could operate "standalone" in the medical sense of an AI model only.
7. Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
- Outcomes Data: The ground truth was mortality, which is a definitive clinical outcome.
8. Sample Size for the Training Set
The document describes a clinical trial (a "test set" or pivotal study) evaluating the device in humans. It does not mention a "training set" in the context of machine learning or AI model development. The device itself is electro-mechanical, not an AI algorithm that would typically require a training set in that sense.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no mention of a machine learning "training set" for an AI algorithm.
§ 870.5900 Thermal regulating system.
(a)
Identification. A thermal regulating system is an external system consisting of a device that is placed in contact with the patient and a temperature controller for the device. The system is used to regulate patient temperature.(b)
Classification. Class II (performance standards).