Abstract: The present invention relates to an improved apparatus and method for measuring blood pressure. Both include a first sensor for detecting an instantaneous pulse rate, an inflatable cuff, and a second sensor to monitoring the pressure within the cuff. The cuff sensor adapted to detect oscillometric complexes associated with a patient's pulse. Both the apparatus and the method provide for detecting arrhythmia from the patient's instantaneous pulse rate. A characteristic of the oscillometric complexes is measured, and match determination means provided for determining whether at least two adjacent oscillometric complexes are equivalent. A first set matching criteria are used under normal conditions. A second set of matching criteria are used when arrhythmia are detected. A controller is provided for controlling the pressure within the cuff. At the outset of a blood pressure measurement the cuff is inflated to a pressure greater than the patient's systolic pressure.

Abstract: An automated sphygmomanometer which utilizes quality algorithms to stop any further analysis at various points during a blood pressure determination because of corrupted data. If the data is so corrupted that giving blood pressure numbers is inappropriate, this is recognized and the determination stopped. The quality algorithms make a decision to get more data with the hope of improving the blood pressure estimation. The request for data occurs both before and/or after a curve fitting process, if such a process is utilized. Some information is also provided to the cuff pressure control function about which pressure levels would be best for gathering the additional data. The quality algorithms are also used to make a decision as to whether it is appropriate to publish the blood pressure values obtained. Control parameters (weights) may be set within the blood pressure algorithm to help with other aspects of the NIBP algorithm and improve the quality of the final published numbers.

Abstract: A conical blood pressure cuff having an integrated inflatable bladder is provided. The cuff is formed of a flexible compliant laminate having at least first and second layers which are impermeable to air. The cuff is formed having first and second arcuate edges, the second edge having a smaller radius than the first edge. Radial edges extend between the first and second arcuate edges. An air-tight rectangular pocket forms the inflatable bladder between the first and second layers. A tube is provided communicating with the interior of the pocket formed between the laminated layers. Air may be pumped the through the tube to inflate the bladder. Similarly, the bladder may be deflated by removing air from the pocket through the tube.

Abstract: A signal enhancing and artifact reducing blood pressure cuff for use during the non-invasive measurement of blood pressure. The non-invasive blood pressure cuff has an inflatable bladder and a semi-rigid insert disposed over an outer side of the inflatable bladder for enhancing a blood pressure signal by reducing blood pressure signal attenuation. The semi-rigid insert also acts to reduce the effects of external artifact on the inflatable bladder of the blood pressure cuff. The blood pressure cuff has the insert disposed over the outer side of the inflatable bladder to substantially cover the inflatable bladder when the cuff is wrapped around the limb of the subject. An optional damping device made of an impact absorbing material may be disposed over the outer side of the insert to further reduce the effects of external artifacts. A pocket may be formed over the outer side of the cuff to hold the insert.

Abstract: A reconfigurable user interface for a modular patient monitor which selectively populates menus for operator selection based on the parameters which are available at any given time. Due to event processing, when a parameter module is added or removed from the system, the reconfigurable user interface is updated immediately to reflect the addition or subtraction of the associated parameter. A flash box in each menu provides shortcuts to the most likely menu option in response to asynchronous events such as alarms and the like. The flash box also assists the operator with the particular steps that must be followed to properly setup or operate a particular feature of the system. Since the menus are not modal, an operator may navigate the menus without making any selections or changing the state of the device.

Abstract: An automated sphygmomanometer which triggers a blood pressure determination upon detection of a significant change in the patient's heart rate variability (HRV). The HRV can be measured directly from the NIBP signal or, when a multiparameter monitor is used, the HRV can be measured from the ECG signal or the NIBP signal. HRV is continuously monitored and the baseline HRV is correlated with baseline blood pressure values. Changes in HRV are displayed continuously on a display so that the clinician can determine whether to initiate an NIBP measurement or, on the other hand, the NIBP measurement can be triggered automatically in response to a change in HRV without any intervention by the clinician. Alternatively, the patient monitor can "learn" the correlation between HRV and blood pressure changes and only alert the clinician when a significant change in HRV has taken place.

Abstract: An automated non-invasive blood pressure (NIBP) monitor having a stat mode of operation wherein several cycles of blood pressure measurement are undertaken in rapid succession by inflating a cuff on an appendage of the patient in order to quickly provide a clinician with readings of blood pressure and pulse rate. The NIBP monitor adaptively determines a minimum wait time between stat mode blood pressure measurement cycles by recognizing that the minimum wait time is proportional to the area under the pressure-time curve of the previous inflation/deflation measurement cycle. The calculated area is divided by a clinical constant derived from sampled patient data to determine the minimum wait time. The minimum wait time between blood measurement cycles so determined allows for venous return of blood that has accumulated in a patient's extremity and minimizes the discomfort experienced by the patient while maximizing the amount of collected data.

Abstract: A sling for use with a noninvasive blood pressure monitor which is designed to minimize contact by external objects with an inflatable cuff which surrounds a patient's limb during blood pressure measurements. The sling comprises an arm rest having supporting straps for supporting the patient's limb at at least two locations so as to define an unsupported space therebetween adapted to accept the inflatable cuff such that the inflatable cuff does not touch the straps or external objects. Preferably, the sling comprises two braces having bottom surfaces to serve as a base for the sling, linking members having ends which are attached to the braces so that the linking members extend between the braces, and two supporting straps, attached to and extending between two linking members, for supporting the patient's arm.

Abstract: An apparatus and method of non-invasive measurement of a chosen region (4) within a body (2), using the transmission of an ultrasonic pulse and the measurement of back scattered optical radiation which has been modulated by the ultrasonic pulse at the region of interest. There may be two or more ultrasonic transmitters (10, 14) to allow control of the vibration of the ultrasonic pulses at the region (4) of interest.

Abstract: A failsafe supervisor system for a processing module of a modular multi-parameter patient monitor which detects a module error or malfunction, places such module in a safe state, and alerts the operator to improper operation of the patient monitor module processor hardware or software. Upon detection of a hardware or software error, an inconsistent system/module time-base check, or other malfunctions during module operation, the impaired parameter module and its associated parameter data gathering apparatuses are powered down and the patient monitor system electrically isolates the impaired module in a failsafe manner to a safe state while permitting other parameter modules to continue with their normal operation. The failsafe supervisor system preferably includes a watchdog timer and discrete logic incorporated with the parameter module's microprocessor control system.

Abstract: An apparatus for non-invasive measurement within a human or animal body with an emitter for emitting electromagnetic radiation into the human or animal body and a detector for detecting the scattered and attenuated radiation. The detector comprises a first principal detector and at least one second reference detector. The second detector is disposed a distance from the emitter which is less than the distance of the first principal detector from the emitter. The second detector is disposed on a line of radius from the emitter which forms an angle with the line of the radius from the emitter on which the first principal detector lies.

Abstract: An automated sphygmomanometer which automatically determines when a blood pressure determination needs to be made. During a "guard mode" determination, a cuff on an appendage of the patient is frequently inflated to a check pressure, which is preferably below the patient's mean arterial pressure ("MAP"), and the signature (shape, amplitude, pulse period, etc.) of the measured oscillometric signal is compared to a stored signature of a portion of an oscillometric signal at a corresponding portion of the oscillometric envelope determined during a previous blood pressure determination. If these signals differ by some predetermined amount, it is determined that the patient's blood pressure has changed significantly and that a new blood pressure determination needs to be conducted immediately. These guard mode determinations are made in addition to the normal blood pressure determinations made at predetermined intervals typically selected by the user.

Abstract: A series of blood pressure cuffs is provided having two indications of size thereon. The first indication of size is preferably a sequential system of numbers numbering the size of the cuffs from smallest to largest. The second system of size indication is a caricature depiction of animals of increasing size on each of the respective increasing cuff sizes. For example, five cuffs may be sized from smallest to largest having depicted thereon a goldfish, a rabbit, a duck, a dog and a dinosaur.

Abstract: A catheter needle having surface indication thereon and process for forming such catheter by laser marking of the needle with a visual surface indicator of the terminus of the catheter tube.

Abstract: A method and apparatus are described for determining characteristics of peripheral arterial volume and compliance. A blood pressure cuff is inflated and deflated around a limb of the body and pressure measurements are taken. The volume of air removed from the cuff is determined in a quantifiable manner, such as by expelling air through an orifice of known characteristics or using a volume of known characteristics. The detected pressures and volume of air removed are used to compute oscillation volume, which in turn is used to display arterial capacity and compliance as a function of transmural pressure and time. Arterial capacity may be displayed in terms of arterial radius, arterial cross-sectional area, or arterial volume. A display of these characteristics as a function of pre and post anesthetic administration is particularly useful to the anesthesiologist and surgeon.

Abstract: A process and product and apparatus are disclosed wherein a laser is used to form a conical tapered tip on a catheter product. The catheter is placed on an insertion needle prior to the formation process, thus eliminating the problems associated with wearing out forming tooling. The process and product further call for the use of the laser to create a surface effect on the cannula to indicate the terminus of the catheter.

Abstract: A new catheter stick protector is described having a metal flap clip which snaps down into place to prevent return of the needle through the protector device once withdrawn. The device is small and received over the needle to provide an interface between the needle hub and the hub of a catheter like product. A sleeve of hydrophobic or fluid impermeable material is provided and attached at one end to the needle hub and at a second end to the tip protector. The length of the material is selected to hold the tip protector in a position just extending beyond the tip of the needle of a catheter inserter.

Abstract: A method and apparatus are described for determining characteristics of peripheral arterial volume and compliance. A blood pressure cuff is inflated and deflated around a limb of the body and pressure measurements are taken. The volume of air removed from the cuff is determined in a quantifiable manner, such as by expelling air through an orifice of known characteristics or by means of a volume of know characteristics. The detected pressures and volume of air removed are used to compute oscillation volume, which in turn is used to display arterial capacity and compliance as a function of transmural pressure and time. Arterial capacity may be displayed in terms of arterial radius, arterial cross-sectional area, or arterial volume. Also, systolic and pulse pressures are determined using only these determined values.

Abstract: A process is provided wherein a laser is used to shape and/or trim a polymer tubular catheter material while in situ on a metal insertion needle or cannula. The laser process seals the interface between the polymer catheter material and the metal cannula to prevent the flow of blood between the tubular catheter and the introducing cannula during insertion into a patient. The interface is of sufficient strength to resist such blood flow, but still sufficiently weak to prevent the removal of the cannula needle after insertion into a patient.