232results about How to "Increase perfusion" patented technology

A combination of a patient core temperature sensor and the dual-wavelength optical sensors in an ear probe or a body surface probe improves performance and allows for accurate computation of various vital signs from the photo-plethysmographic signal, such as arterial blood oxygenation (pulse oximetry), blood pressure, and others. A core body temperature is measured by two sensors, where the first contact sensor positioned on a resilient ear plug and the second sensor is on the external portion of the probe. The ear plug changes it's geometry after being inserted into an ear canal and compress both the first temperature sensor and the optical assembly against ear canal walls. The second temperature sensor provides a reference signal to a heater that is warmed up close to the body core temperature. The heater is connected to a common heat equalizer for the temperature sensor and the pulse oximeter. Temperature of the heat equalizer enhances the tissue perfusion to improve the optical sensors response. A pilot light is conducted to the ear canal via a contact illuminator, while a light transparent ear plug conducts the reflected lights back to the light detector.

A system including an implantable neurostimulator device capable of modulating cerebral blood flow to treat epilepsy and other neurological disorders. In one embodiment, the system is capable of modulating cerebral blood flow (also referred to as cerebral perfusion) in response to measurements and other observed conditions. Perfusion may be increased or decreased by systems and methods according to the invention as clinically required.

Methods, devices, and systems for a) revascularization and / or b) performing other medical procedures at vascular or non-vascular intracorporeal locations within a mammalian body. The methods generally comprise the formation of at least one extravascular passageway from a blood vessel to a vascular or non-vascular target location. In the revascularization methods the extravascular passageway is utilized for blood flow. In the medical procedure methods the extravascular passageway is utilized as a conduit for accessing or performing procedures at the vascular or non-vascular target location. Also disclosed are catheter devices and systems which are useable to form the extravascular passageways of the invention, as well as apparatus for modifying, maintaining and / or closing such extravascular passageways.

Patients having diminished circulation in the cerebral vasculature as a result of stroke or from other causes such as cardiac arrest, shock or head trauma, or aneurysm surgery or aortic surgery, are treated by flowing an oxygenated medium through an arterial access site into the cerebral vasculature and collecting the medium through an access site in the venous site of the cerebral vasculature. Usually, the cold oxygenated medium will comprise autologous blood, and the blood will be recirculated for a time sufficient to permit treatment of the underlying cause of diminished circulation. In addition to oxygenation, the recirculating blood will also be cooled to hypothermically treat and preserve brain tissue. Isolation and cooling of cerebral vasculature in patients undergoing aortic and other procedures is achieved by internally occluding at least the right common carotid artery above the aortic arch. Blood or other oxygenated medium is perfused through the occluded common carotid artery(ies) and into the arterial cerebral vasculature. Usually, oxygen depleted blood or other medium leaving the cerebral vasculature is collected, oxygenated, and cooled in an extracorporeal circuit so that it may be returned to the patient. Occlusion of the carotid artery(ies) is preferably accomplished using expansible occluders, such as balloon-tipped cannula, catheters, or similar access devices. Access to the occlusion site(s) may be open surgical, percutaneous, or intravascular.

In one embodiment, the invention provides a medical method for treating a person and comprises repeatedly compressing the person's chest. While repeatedly compressing the person's chest, the method further includes repeatedly delivering a positive pressure breath to the person and extracting respiratory gases from the person's airway using a vacuum following the positive pressure breath to create an intrathoracic vacuum to lower pressures in the thorax and to enhance blood flow back to the heart.

Devices, systems and methods by which the real or apparent renovascular perfusion and intrarenal pressure may be selectively and controllably increased. By selectively and controllably increasing renovascular perfusion and interstitial hydrostatic pressure when the heart is unable to pump sufficient blood or when renal perfusion is suboptimal, the present invention reduces or reverses neurohormonal activation and fluid retention, and thereby minimizes their deleterious effects on the heart, vasculature, kidneys and other body systems.

A system and method for monitoring at least one chamber of a heart (e.g., a left ventricular chamber) during delivery of extrasystolic stimulation to determine if the desired extra-systole (i.e., ventricular mechanical capture following refractory period expiration) occurs. The system includes an implantable or external cardiac stimulation device in association with a set of leads such as epicardial, endocardial, and / or coronary sinus leads equipped with motion sensor(s). The device receives and processes acceleration sensor signals to determine a signal characteristic indicative of chamber capture resulting from one or more pacing stimulus delivered closely following expiration of the refractory period. A threshold optimization method optionally evaluates capture and at least one of: runs an iterative routine to establish or re-establish chamber capture for the PESP therapy, sets a logical flag relating to chamber capture status and stores parameter(s) relating to successful chamber capture for one or more subsequent cardiac cycles.

In one embodiment, a method for improving the cardiac output of a patient who is suffering from pulseless electrical activity or shock and yet still displays some myocardial wall motion comprises sensing myocardial activity to determine the presence of residual left ventricular pump function having a contraction or ejection phase and a filling or relaxation phase. In such cases, a compressive force is repeatedly applied to the chest based on the sensed myocardial activity such that the compressive force is applied during at least some of the ejection phases and is ceased during at least some of the relaxation phases to permit residual cardiac filling, thereby enhancing cardiac output and organ perfusion. Also incorporated may be a logic circuit capable of utilizing multiple sensing modalities and optimizing the synchronization pattern between multiple phasic therapeutic modalities and myocardial residual mechanical function.

A system and method for monitoring at least one chamber of a heart (e.g., a left ventricular chamber) during delivery of a refractory period stimulation (RPS) therapy to determine if the desired non-capture (i.e., lack of ventricular mechanical capture due to refractory period stimulation) occurs. The system includes an implantable or external cardiac stimulation device in association with a set of leads such as epicardial, endocardial, and / or coronary sinus leads equipped with motion sensor(s). The device receives and processes acceleration sensor signals to determine a signal characteristic indicative of chamber capture due to pacing stimulus delivery, non-capture due to RPS therapy delivery, and / or contractile status based on the qualities of evoked response to pacing stimulation.

An expandable introducer sheath can actively be induced to reduce in diameter or enlarge in diameter due to a braided internal structure that has axial strands connected to its distal end. The introducer sheath is delivered to the blood vessel or other tubular member of the body in a smaller diameter configuration with the axial strands in compression. The catheter is flexible and can be delivered to eccentrically shaped and tortuous vessels. Once the catheter is in position, the axial strands are placed into tension to cause the introducer sheath to assume a larger diameter configuration that will help straighten out tortuous vessels. The access site into the blood vessel is expanded via a radial expansion that is less traumatic. Passage of a larger interventional catheter can proceed through the larger diameter sheath configuration. If the interventional catheter has a smaller shaft, the introducer sheath can be reduced in diameter to come into close approximation with the shaft to reduce the opening size at the access site. The sheath can be removed over time with incremental reductions in its diameter to allow the access site time to relax to a smaller size for improved vascular sealing.

The invention describes compositions of peptide analogs that are active in blood or cleavable in blood to release an active peptide. The peptide analogs have a general formula: A-(Cm)x-Peptide, wherein A is hydrophobic moiety or a metal binding moiety, e.g., a chemical group or moiety containing 1) an alkyl group having 6 to 36 carbon units, 2) a nitrilotriacetic acid group, 3) an imidodiacetic acid group, or 4) a moiety of formula (ZyHisw)p, wherein Z is any amino acid residue other than histidine, His is histidine, y is an integer from 0-6; w is an integer from 1-6; and p is an integer from 1-6; wherein if A has alkyl group with 6 to 36 carbon units x is greater than 0; and Cm is a cleavable moiety consisting of glycine or alanine or lysine or arginine or N-Arginine or N-lysine, wherein x is an integer between 0-6 and N may be any amino acid or none. The peptide analogs are complexed with polymeric carrier to provide enhanced half-life.

The present invention relies on a controller-transmitter device to deliver ultrasound energy into cardiac tissue in order to directly improve cardiac function and / or to energize one or more implanted receiver-stimulator devices that transduce the ultrasound energy to electrical energy to perform excitatory and / or non-excitatory treatments for heart failure. The acoustic energy can be applied as a single burst or as multiple bursts.

Methods and devices provide for temporary partial aortic occlusion to achieve diversion of blood flow to the brain in patients suffering from cerebral ischemia. The device includes an expandable frame and membrane that is inserted into the aorta to partially occlude blood flow.

The present invention provides a portable device for enhancing circulation in a limb comprising at least one strap for encircling the limb, a motor and a mechanism driven by said motor for intermittently actuating a first transition from a relaxed state to a strained state of the strap and a second transition from the strained state to the relaxed state. The mechanism includes at least one energy storing element operatively disposed between the motor and the strap and at least one energy releasing mechanism coupling between the energy storing element and the strap. The energy releasing mechanism enables fast release of energy stored in said storing element and the use of the energy so released to effectuate at least one abrupt transition between said relaxed and strained states.

A method for improving the cardiac output of a patient who is suffering from pulseless electrical activity or shock and yet still displays some myocardial wall motion including sensing myocardial activity to determine the presence of residual left ventricular pump function having a contraction or ejection phase and a filling or relaxation phase. In such cases, a compressive force is repeatedly applied to the chest based on the sensed myocardial activity such that the compressive force is applied during at least some of the ejection phases and is ceased during at least some of the relaxation phases to permit residual cardiac filling, thereby enhancing cardiac output and organ perfusion. Also incorporated may be a logic circuit capable of utilizing multiple sensing modalities and optimizing the synchronization pattern between multiple phasic therapeutic modalities and myocardial residual mechanical function.

An apparatus and methodological framework are provided, named perfusion angiography, for the quantitative analysis and visualization of blood flow parameters from DSA images. The parameters, including cerebral blood flow (CBF) and cerebral blood volume (CBV), mean transit time (MTT), time-to-peak (TTP), and Tmax, are computed using a bolus tracking method based on the deconvolution of time-density curves on a pixel-by-pixel basis. Individual contrast concentration curves of overlapping vessels can be delineated with multivariate Gamma fitting. The extracted parameters are each transformed into parametric maps of the target that can be color coded with different colors to represent parameter values within a particular set range. Side by side parametric maps with corresponding DSA images allow expert evaluation and condition diagnosis.

Apparatus, systems, and methods in which a catheter-based pump is used are disclosed. The catheter-based pump is placed within the inferior vena cava of a patient. The catheter-based pump has a variable obstructor, such as a balloon or some other artificial obstruction, which is sized and dimensioned to compartmentalize the inferior vena cava into an upstream region and a downstream region of the inferior vena cava. The catheter-based pump is configured to pump blood from the upstream region to a fluid line that discharges blood to a discharge location in the downstream region. Thus, a suitable pressure gradient across the organ is provided, which can benefit organ function.

In one embodiment, the invention provides a device for decreasing intracranial or intraocular pressures. The device comprises a housing having an inlet opening and an outlet opening that is adapted to be interfaced with a person's airway. The device further includes a valve system that is operable to regulate respiratory gas flows through the housing and into the person's lungs during spontaneous or artificial inspiration. The valve system assists in lowering intrathoracic pressures during each inspiration to repetitively lower pressures in the venous blood vessels that transport blood out of the head to thereby reduce intracranial or intraocular pressures.

In one embodiment, the invention provides a medical method for treating a person and comprises repeatedly compressing the person's chest. While repeatedly compressing the person's chest, the method further includes repeatedly delivering a positive pressure breath to the person and extracting respiratory gases from the person's airway using a vacuum following the positive pressure breath to create an intrathoracic vacuum to lower pressures in the thorax and to enhance blood flow back to the heart.

Systems, methods and devices are provided for the targeted treatment of a variety of medical conditions by directly neuromodulating a target anatomy associated with the condition while minimizing or excluding undesired neuromodulation of other anatomies. Typically, the target anatomy includes one or more dorsal root ganglia, dorsal roots, dorsal root entry zones, or portions thereof. Such target stimulation areas are utilized due in part to their effect on the sympathetic nervous system.

There is provided a pulsatile blood pump (10) for implantation into a patient. The pulsatile blood pump comprises a substantially tubular body (12) a flexible membrane (14) and a port (16). The substantially tubular body is for replacing a resected portion of a blood vessel of the patient. The substantially tubular body has first and second ends with a blood passageway extending therebetween for the passage of blood. The flexible membrane is attached to the tubular body so as to form a fluid chamber between the flexible membrane and an inner surface of the tubular body. The flexible membrane thereby separates the fluid chamber from the blood passageway. The tubular body comprises the port. The port is arranged to allow fluid to flow into and out of the fluid chamber such that the volume of the fluid chamber increases and the volume of the blood passageway decreases when fluid flows into the fluid chamber via the port, and such that the volume of the fluid chamber decreases and the volume of the blood passageway increases when fluid flows out of the fluid chamber via the port. The blood pump is thereby enabled to pump blood along the blood passageway.

There is provided a non-contact, passively suspended blood pump that includes (a) a housing; (b) a pump rotor within the housing, wherein the pump rotor has a first end and a second end, and an axis of rotation; (c) a first axial thrust bearing across a first axial gap, between the first end and the housing, that axially suspends the first end; (d) a second axial thrust bearing across a second axial gap, between the second end and the housing, that axially suspends the second end; (e) a first radial hydrodynamic bearing that radially suspends the first end; and (f) a second radial hydrodynamic bearing that radially suspends the second end. Determining pump differential pressure by monitoring rotor axial position allows automatic physiologic control.

Disclosed are methods, compositions, and cells useful for increasing insulin sensitivity, as well as lack of insulin production in a host in need thereof. One aspect of the invention discloses methods of increasing skeletal muscle perfusion through administration of cells capable of directly and / or indirectly stimulatory of angiogenesis and / or vascular responsiveness. Another aspect provides means of increasing sensitivity to insulin through administration of a cell composition capable of integrating into host insulin responsive tissue and upregulating responsiveness either through mobilization of host cells capable of responding to insulin, mobilization of host cells capable of endowing insulin responsiveness on other host cells, exogenously administered cells taking the role of insulin responsiveness, or exogenously administered cells endowing insulin responsiveness on other host cells. Another aspect comprises modifying said host to allow for concurrent insulin sensitization and upregulated production of insulin.

A multilumen catheter that maximizes the blood flow into and out of the patient's vasculature while also providing for passive and / or active perfusion of tissue downstream of where the catheter resides in the vasculature. The inventive catheter comprises a proximal end, a first distal and a second distal end. Lumens extending from the proximal end to each of these distal ends provide for blood circulation within one or between two blood vessels. At least one aperture in one of the lumens positioned near the proximal end provides for active perfusion of blood to the patient's vasculature downstream of where the aperture resides in the vasculature when the catheter is inserted into the patient for treatment. The inventive catheter may comprise a third lumen positioned entirely within the patient's vasculature, providing passive perfusion of blood to the patient's vasculature downstream of where the third lumen resides in the vasculature when the catheter is inserted into the patient for treatment.

The invention relates to a bioreactor for cultivating cells having a filter bag for separating culture fluid and cells, the filter medium of the filter bag having a degree of swelling of less than 1%. The bioreactor according to the invention is characterized by a high durability of the filter bag thereof.

An aortic occluder catheter with expandable balloons for increasing cerebral blood blow has one or more balloons on a catheter shaft. To assist the balloon in bearing up against arterial blood flow while positioned retrograde in the aorta, the balloon is bonded to the catheter shaft in tension.

A method and apparatus using photostimulation to treat or pretreat a sample site prior to analyte property estimation is presented. More particularly, photonic-stimulation at and / or near at least one sample site is used to enhance perfusion of the sample site leading to reduced errors associated with sampling. This allows an analyte property determination in well perfused regions of the body while sampling at a more convenient less well perfused region of the body.