Certain aspects relate to percutaneous sheaths for medical procedures as well as to related systems and methods. For example, a system for performing a percutaneous assisted medical procedure can include a percutaneous sheath. The percutaneous sheath can include a first conduit for providing aspiration into the kidney and a second conduit for passing a catheter into the kidney. The system can also include an aspiration catheter configured to be inserted into the kidney through the second conduit of the percutaneous sheath. A fluidics system can include an irrigation source comprising a pump and an aspiration source comprising a vacuum. The irrigation source can be connected to a fluid inlet of the percutaneous sheath that is connected to the first conduit. The aspiration source can be connected to the aspiration catheter.

A pressure sensitive device including a body having a proximal portion and a distal portion opposite the proximal portion, the distal portion being made of a shape memory alloy, a flexible diaphragm at least partially surrounding the body and defining a fluid chamber between the flexible diaphragm and the distal portion of the body, and a non-compressible fluid disposed within the flexible diaphragm and exhibiting a hydraulic pressure in communication with the flexible diaphragm.

A transvascular pressure sensing device including a housing having a proximal portion and a distal portion opposite the distal portion, the proximal portion including a blood pressure sensor disposed therein, a compliant balloon surrounding at least a portion of the housing and defining a fluid chamber therebetween, the fluid chamber including a first portion defining a first volume and a second portion defining a second volume greater than the first volume, and a fluid disposed within the fluid chamber and exerting a hydraulic pressure on the balloon, the blood pressure sensor being configured to measure a change in the hydraulic pressure when a force is distributed over the second portion of the balloon.

MRI compatible localization and/or guidance systems for facilitating placement of an interventional therapy and/or device in vivo include: (a) a mount adapted for fixation to a patient; (b) a targeting cannula with a lumen configured to attach to the mount so as to be able to controllably translate in at least three dimensions; and (c) an elongate probe configured to snugly slidably advance and retract in the targeting cannula lumen, the elongate probe comprising at least one of a stimulation or recording electrode. In operation, the targeting cannula can be aligned with a first trajectory and positionally adjusted to provide a desired internal access path to a target location with a corresponding trajectory for the elongate probe. Automated systems for determining an MR scan plane associated with a trajectory and for determining mount adjustments are also described.

Devices, systems, and methods for monitoring patient hemodynamic status, systemic vascular resistance, reversal of cardiac and respiratory rates, and patient respiratory volume or effort are disclosed. A peripheral venous pressure is measured and used to detect levels, changes, or problems relating to patient blood volume. The peripheral venous pressure measurement is transformed from the time domain to the frequency domain for analysis. A heart rate frequency is identified, and harmonics of the heart rate frequency are detected and evaluated to determine, among other things, hypovolemia or hypervolemia, systemic vascular resistance, and of cardiac and respiratory rates, and patient respiratory volume or effort.

A biomarker detector used to detect and notify a user of a biological substance. More specifically, a biomarker detector coating layered on a surgical instrument that enables a user of the surgical instrument to know when a critical bodily fluid, such as cerebrospinal fluid, or critical tissue, such as nerve tissue, has been reached by the surgical instrument, thereby allowing the user to react accordingly and avoid iatrogenic injury.

An apparatus and method is provided for intraoperative tissue stimulation during port-based surgery. The apparatus includes an access port and electrical terminals attached to the access port for tissue stimulation. In an alternative embodiment, the apparatus may include an access port, with or without electrical terminals attached to the access port for tissue stimulation, and electrocorticography sensors attached to the access port. The method includes inserting an access port into a tissue, applying an electrical potential to the tissue using electrical terminals attached to the access port, and measuring consequent neural activity using electrocorticography sensors attached to the access port.

An implantable apparatus for physiological measurement in a host organism has an implantable sample chamber having a measurement port and live cells that are treated to fluoresce in response to light having an excitation wavelength. An optical sensor housing implanted within the host organism has a window to convey excitation light output and receive fluorescent light; a coupling that couples the measurement port of the sample chamber to the window; an optical chamber partitioned into an excitation sub-chamber and a detection sub-chamber, wherein both sub-chambers are in optical communication with the window; an excitation source energizable to direct excitation light through the excitation sub-chamber and to the window; and a detector in the path of fluorescent light received from the live cells. A signal processing apparatus is energizable to acquire and process a detector signal and to transmit a processed signal that is indicative of fluorescent light energy.

Devices, systems, and methods for monitoring patient hemodynamic status, systemic vascular resistance, reversal of cardiac and respiratory rates, and patient respiratory volume or effort are disclosed. A peripheral venous pressure is measured and used to detect levels, changes, or problems relating to patient blood volume. The peripheral venous pressure measurement is transformed from the time domain to the frequency domain for analysis. A heart rate frequency is identified, and harmonics of the heart rate frequency are detected and evaluated to determine, among other things, hypovolemia or hypervolemia, systemic vascular resistance, and of cardiac and respiratory rates, and patient respiratory volume or effort.

An apparatus for insertion of a medical device in the skin of a subject is provided, as well as methods of inserting medical devices.