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This page describes products and general use; it is not medical advice.
An intracranial pressure (ICP) monitor is a regulated medical device: in the US it is defined in 21 CFR 882.1620 as a device for short-term monitoring and recording of intracranial pressures and pressure trends, and it is Class II. Clinic staff, buyers and students use this page to tell apart the parts of an ICP monitoring system (implanted sensor, cable, bedside monitor) and the sensor types the term covers. It is used in intensive care and operating room settings.
What an intracranial pressure monitor is
The FDA regulation for the device type states that an intracranial pressure monitoring device is “a device used for short-term monitoring and recording of intracranial pressures and pressure trends,” and that it includes the transducer, the monitor, and interconnecting hardware. The product code is GWM and the classification is Class II (performance standards). A health-system patient page describes the purpose plainly: the monitor senses the pressure inside the skull and sends measurements to a recording device.
Who uses it: the bedside monitor is used by intensive care and operating room teams; buyers and biomedical staff in hospitals specify and maintain the equipment.
Parts: sensor, cable and bedside monitor
The regulation’s three elements map onto what is bought and installed. An FDA 510(k) summary for the CereLink ICP Monitor and Extension Cable (K232890, decision letter dated February 4, 2024) shows how one system divides them:
- Sensor: a solid-state sensor placed directly in parenchymal tissue, or integrated into an external ventricular drainage catheter placed in the ventricle.
- Extension cable: connects the monitor’s ICP input to the implanted sensor. The monitor in that submission has one input channel for the sensor via the extension cable and one output channel to a compatible patient monitor.
- Bedside monitor: a transportable unit with a 7-inch colour touch screen that can be used with gloves and an internal rechargeable battery.
The same submission lists the monitor’s intended roles: an interface between compatible strain-gauge pressure transducers and standard physiological pressure monitoring systems, and an independent monitor that displays mean, systolic and diastolic values when no external patient monitor is present. It alarms when ICP falls outside limits the user sets.
Types by sensor placement
| Type | Typical use | Key difference | Source |
|---|---|---|---|
| Intraventricular catheter | Placed in the lateral ventricle | Can also drain cerebrospinal fluid | UCSF Health |
| Parenchymal sensor | Solid-state sensor placed directly in brain tissue, or integrated into a ventricular catheter | Sensor sits in tissue; connects to the monitor through an extension cable | FDA K232890 |
| Subdural screw or bolt | A hollow screw through a hole in the skull; sensor records from the subdural space | Sensor sits in the subdural space | UCSF Health |
| Epidural sensor | Placed between the skull and the dura | Less invasive; cannot remove excess cerebrospinal fluid | UCSF Health |
Where the sensor is integrated into a drainage catheter, the system overlaps with the equipment described in the external ventricular drain guide.
What the monitor displays and stores
For the monitor described in K232890, the listed functions are an ICP waveform, a mean ICP numeric, trends, and trend statistics (pressure time dosage, time above threshold, boxplot and histogram). It stores 14 days of mean ICP values and 24 hours of waveform, saves screenshots, supports USB download and real-time USB streaming, and can connect to an external patient monitor. These are the features of one cleared product, not a requirement for the device type.
FDA classification
21 CFR 882.1620 (checked 2026-10-30) places intracranial pressure monitoring devices in Class II under product code GWM. The K232890 submission lists a predicate (K210993) and records that the manufacturer remains subject to the Quality System regulation (21 CFR 820) and medical device reporting. For the wider framework see what is a medical device and the 510(k) and De Novo submission template guide. Monitoring equipment more generally is covered in choosing diagnostic and patient monitoring equipment; related supplies are listed under diagnostic and monitoring equipment.
Safe use and handling basics
Sensor placement is a clinical procedure performed by trained clinicians, and this page does not describe it. The risks listed by UCSF Health for ICP monitoring are bleeding, brain herniation or injury from increased pressure, damage to brain tissue, inability to find the ventricle or place the catheter, infection, and the risks of general anesthesia. Device problems involving a cleared monitor are reportable through the manufacturer and FDA medical device reporting channels; see medical device reporting (MDR).
Common mistakes
- Treating the monitor and the sensor as one product. The regulation covers the transducer, monitor and interconnecting hardware together; they are separate items in a system such as K232890.
- Confusing ICP monitoring with drainage. A sensor in tissue measures pressure; an intraventricular catheter can also drain fluid, and an epidural sensor cannot.
- Assuming one cleared monitor’s storage and display features apply to every model. The 14-day and 24-hour figures belong to the K232890 monitor.
Frequently asked questions
What is an intracranial pressure monitor?
It is a device used for short-term monitoring and recording of intracranial pressures and pressure trends; the US regulation says it includes the transducer, monitor and interconnecting hardware.
What FDA class is an intracranial pressure monitor?
Class II, product code GWM, under 21 CFR 882.1620.
What are the parts of an ICP monitoring system?
In the cleared system described above: an implanted sensor, an extension cable and a bedside monitor, with an output to a compatible patient monitor.
Is an ICP monitor the same as an external ventricular drain?
No. A sensor measures pressure; an intraventricular catheter can also drain fluid, and a sensor can be integrated into such a catheter. See the external ventricular drain guide.
Sources
- eCFR, 21 CFR 882.1620, Intracranial pressure monitoring device: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-882/subpart-B/section-882.1620 (checked 2026-10-30)
- FDA 510(k) K232890, CereLink ICP Monitor and Extension Cable, Integra LifeSciences: https://www.accessdata.fda.gov/cdrh_docs/pdf23/K232890.pdf (checked 2026-10-30)
- UCSF Health, Intracranial pressure monitoring: https://www.ucsfhealth.org/care/medical-tests/intracranial-pressure-monitoring (checked 2026-10-30)
