Abstract: An infant care apparatus having a canopy movable vertically with respect to an infant platform. The canopy has a lower edge mating with upper peripheral edges of a plurality of vertical walls forming an infant compartment. At least one of the vertical walls is a door pivotally affixed to the infant platform and rotates between open and closed positions. A seal is located on the lower edge of the canopy to seal against the upper peripheral edge of the vertical walls. An elongated flange of the seal is affixed to the canopy by hardware and a cover flap extends downwardly from the upper edge of the flange to cover the hardware. A sealing flap extends downwardly and inwardly toward the infant compartment from the lower edge of the flange. A flexible material is co-extruded with the seal for the sealing flap and a hinge between the flange and the cover flap.

Abstract: The present invention provides a reduced wire count voltage-drop sense system and method wherein the voltage drop across a load device is determinable using only one sense lead regardless of the number of load devices. In one embodiment, the voltage drop across any one of four LEDs (220A-D) in a photoplethysmographic probe when a drive current is applied therethrough via one of four input drive leads (230A-D) connected to separate LED terminals (222A-D) is determinable from a first voltage drop and a second voltage drop, for example, by subtracting the second voltage drop, or a portion thereof, from the first voltage drop. The first voltage drop is measurable across a terminal (232A-D) of the input drive lead (230A-D) connected to the LED (220A-D) across which the voltage drop is to be determined and a terminal (252) of a sense lead (250) connected to a common LED terminal (224).

Abstract: A photoplethysmographic system and method is provided to identify compatible sensors to monitors and/or for determining sensor attributes. The improved system includes a signal generation means for providing an interrogation signal, an identifying means coupled between a first and second sensor terminal operable to produce multiple outputs upon application of the interrogation signal in two modes of operation, and a processor to interpret the outputs. When the interrogation signal is applied to a sensor terminal in a first mode, a first output is obtained. Upon applying the same interrogation signal to the sensor terminal in a second mode, a second output is obtained. The first and second outputs may then be utilized by the processor comprising, for example, a photoplethysmographic monitor to yield enhanced sensor information. The disclosed method may be carried out utilizing the inventive photoplethysmographic system.

Abstract: Processing of plethysmographic signals via the cepstral domain is provided. In one embodiment, a cepstral domain plethysmographic signal processing method (200) includes the steps of obtaining (210) time domain plethysmographic signals, smoothing (220) the time domain plethysmographic signals, performing (230) a first-stage Fourier transformation of the time domain plethysmographic signals to frequency domain plethysmographic signals, computing (240) power spectrums from the frequency domain plethysmographic signals, scaling (250) the power spectrums with a logarithmic function, performing (260) a second-stage Fourier transformation on log-scaled spectrums to transform the power spectrums into cepstrums, and examining (270) the cepstrums to obtain information therefrom relating to a physiological condition of the patient such as the patient's pulse rate or SPO2 level.

Abstract: A vacuum system for applying vacuum to the body cavity of a patient where a flow switch is provided that is located upstream of a vacuum regulator that can be adjusted to establish the level of vacuum desired to be applied to the patient. The flow switch provides an easy device for the caregiver to activate to fully and positively occlude the vacuum line to the patient. In one embodiment, the flow switch is constructed integral with a regulator having an rotatable actuator having a knob that is rotated to adjust the level of vacuum to the patient such the a caregiver can simply push the actuator knob inwardly to occlude the flow in the patient line and thereafter rotate the actuator knob to establish the desired level of vacuum to the patient.

Abstract: A moisture sump integrated into a carbon dioxide absorber canister provides a collection reservoir for condensate from a patient ventilator system when the carbon dioxide absorber canister is attached to the ventilator system. The volume of the moisture sump is appropriately sized so that the time interval required to collect a maximum amount of condensate interval is not more than the life expectancy of the carbon dioxide absorbing material contained within the canister. The moisture sump allows condensate management of difficult to drain areas such as the inlet to the expiratory check valve of a ventilator system. The removal of the carbon dioxide absorber canister by a patient attendee to replace the carbon dioxide absorbing material ensures that the condensate collected by the integral moisture sump is eliminated from the patient ventilator system.

Abstract: An infant warming apparatus that functions both as an infant incubator as well as an infant warmer. The apparatus has a heater that moves vertically with respect to an infant support during the change in function between an infant incubator and an infant warmer. The heater also has a door or doors that are open when the heater is at or nearing the upper position so that the heater can direct energy toward the infant to warm the infant when acting as an infant warmer and close at or shortly after the heater commences movement to the lower position. When closed, the doors isolate the heater to prevent the inadvertent touching of the heater by the infant or attending personnel and prevents the further radiating of infrared energy toward the infant.

Abstract: A system for facilitating the delivery of a liquid anesthetic agent from an anesthetic bottle to an anesthetic vaporizer. The system includes a bottle adapter, an anesthetic bottle and a filler arrangement positioned on the anesthetic vaporizer. The bottle adapter and filler arrangement each include a keyed configuration such that only the correct type of anesthetic agent can be emptied into the anesthetic vaporizer. The bottle adapter includes an adapter valve assembly that engages a filler valve assembly contained within the filler. The dimensions and arrangement of the adapter valve assembly and the filler valve assembly insure anesthetic agent is delivered to the anesthetic vaporizer only when the anesthetic agent can safely flow from the anesthetic bottle to the anesthetic vaporizer.

Abstract: A nitric oxide delivery system is disclosed that delivers a pulsed volume of NO containing therapeutic gas to a patient upon each inhalation of the patient. The NO delivery system includes certain functions to provide protection against the inadvertent inclusion of NO2 in the therapeutic gas administered to the patient. One of the functions is to provide a purge upon start up of the delivery system apparatus that clears the regulator and conduits of any NO2 that may have formed during the prior idle period of the system. A detector determines the start-up and may automatically carry out the purge cycle or may cause a prompt that is visual or audible to remind the user to carry out the purge cycle manually.

Abstract: An anesthesia system wherein the respiratory system is fitted with interchangeable patient circuit modules that allows a generic fitting in the machine to have affixed, hereto, a module that has ports suitable for connection to various patient breathing circuits. As such, the anesthesia machine can have the patient circuit modules easily changed and thus be adaptable for use with patient breathing circuits such as the circle system, the open/nonrebreathing circuit and the Bain or Mapleson D circuits. A detector system is provided that identifies that particular patient module installed in the anesthesia machine to alert the main CPU and to thus provide the correct flow sensing schemes and flows to the patient breathing circuit then being used.

Abstract: An infant apparatus having a base, a vertically movable hood and a plurality of walls that form an infant compartment. The apparatus has lateral side walls and a front end door that can be individually opened. There is an interlocking engagement between the upper periphery of the lateral walls and hood by a plurality of pins on the hood that engage brackets located at the top of the front and rear end walls. A latching arrangement allows all three doors to be opened. The side lateral doors are latched by a movable latch member that enters an opening in brackets affixed to the front and rear end walls. The front end wall can be moved vertically upwardly to disengage its latching arrangement to enable it to pivot downwardly. An alignment mechanism is also provided to insure that the movable latch members correctly align with the openings in the brackets.

Abstract: A photoplethysmographic measurement system includes an electrical lockout to effectively prevent users, such as patients and medical personnel, from being exposed to high levels of light energy illuminating from light emitters (18) housed within a main instrument (10) when a probe (12) becomes detached from the system during use. The probe (12) is provided with a resistor having a range of resistor values. In use, the electrical lockout frequently or continuously interrogates the probe connection and determines whether the detected value of the resistor falls within predetermined allowable levels. If the probe (12) inadvertently becomes disconnected from the main instrument, the value of the resistor will fall outside of the predetermined allowable levels indicative of an incompatible probe, an improper coupling of the probe, or a complete detachment of the probe. In this case, lockout switch (44) is employed to inhibit activation of the light emitters (18).

Abstract: The present invention is directed to a method and system for use in assessing collateral blood flow to a tissue region of interest (ROI). The method includes the steps of obtaining a first pulsatility measurement and a second pulsatility measurement, wherein one of the pulsatility measurements is obtained with a plurality of arteries supplying blood to the tissue ROI and the other pulsatility measurement is obtained with at least a selected one of such arteries substantially occluded. The method further provides for use of the first and second pulsatility measurements to generate a collateral flow value useful to medical personnel as an objective measure in assessing collateral blood flow to a tissue ROI. The method may further include the step of obtaining a check pulsatility measurement after obtaining a first pulsatility measurement and prior to obtaining a second pulsatility measurement, wherein all of the plurality of the arteries are substantially occluded.

Abstract: A system for detecting sensor off conditions in a pulse oximeter is disclosed. In one implementation, a detector off condition is identified based a volatility of a signal quality of a filtered detector signal. The detector signal is first filtered, for example, to reduce the effects of noise or to otherwise reduce or eliminate components extraneous to the signal of interest. The filtered signal is used to perform a volatility measurement. In this regard, a correlation coefficient may be computed relative to two channels of the filtered signal and a correlation coefficient may be monitored over a moving window to calculate variance values for the correlation coefficient. The resulting variance values may be used alone or in combination with other parameter values to identify a sensor off condition.

Abstract: Differential values, for use in blood oxygenation calculations, are determined based on multiple sample values for each channel of an oximetry system, each such value constituting a data point. In one implementation, each of these data points is defined by a sample window (220, 222 and 224), where the window includes, for example, 7-10 data points. That is, the data points within window (220, 222 or 224) are used to establish a differential value nominally associated with the data sample about which the window is centered. The differential value is calculated based on a mathematical model such as a weighted linear regression analysis. In this manner, output may be provided on a sample-by-sample basis while mitigating noise sensitivity.

Abstract: The invention is directed to reusable, clip-type oximetry sensors that comprise opposing top and bottom members. In one aspect, the sensor includes a resilient spring member interposed between the top and bottom members to provide a closing force, wherein the resilient spring member comprises tensile and compressive portions. That is, upon positioning a patient appendage in the sensor different portions of the resilient spring member are in tension and in compression so as to combinatively provide an enhanced closing force utilized to secure the patient appendage between the top and bottom members. The resilient spring member may be of a molded, monolithic construction, comprising an elastomeric material. In another aspect, the inventive sensor includes cushions interconnected to the top and bottom members via snap-fit engagement. The snap-fit engagement may be provided by a plurality of interconnecting member pairs (e.g.

Abstract: A pulse oximeter (100) includes two or more light sources (102) for transmitting optical signals through an appendage (103) of patient. The sources (102) are operated to transmit code division multiplexed (CDM) signals. That is, the sources (102) are driven by drives (104) in response to signals from a digital processing unit (116) such that the sources (102) are modulated using different code sequences. The code sequences are preferably non-periodic and may be orthogonal to one another. The use of such CDM signals provides certain advantages related to noise reduction.

Abstract: The invention relates to the calibration of a pulse oximeter intended for non-invasively determining the amount of at least two light absorbing substances in the blood of a subject. In order to take human variability into account, the calibration is based on an invariant which is a quotient of two pseudo-isobestic signals. Each pseudo-isobestic signal is a weighted sum of two signals, and the weighted sum is theoretically independent of the relative concentrations of said substances in the blood of the subject. By using theoretical values of the invariant on the one hand, and values based on in-vivo measurements on the other hand, the calibration curve of the pulse oximeter is adapted to the characteristics of each individual patient.

Abstract: A incubator door having a double walled construction where two parallel walls, an inner and an outer wall are spaced apart to form a passageway therebetween. The inner wall is easily removable from the door for cleaning of the interior of the walls by means of a hinge affixed to the outer wall that holds both of the walls together and which has sockets formed therein. The inner wall has tabs at its bottom that fit into the sockets to hold the bottom of the inner door pivotally to the hinge. There is a slot formed in each of the sockets of a sufficient size to allow the thickness of the inner wall to pass through the slot to be removed from the hinge. The other transverse dimension of the tab is larger and does not pass through the slot. Thus, by pivoting the inner wall so that it aligns with the slot, the inner wall can be readily removed from the outer wall. The upper portion of the inner wall is also held from pivoting by a resilient latch that holds the inner wall in position to the outer wall.

Abstract: An infant care apparatus is provided that includes an infant support for underlying the infant. A drawer is provided beneath the infant support and which has a center position where it is generally aligned with the infant support and which is movable bidirectionally from that center position so that it can be moved in either direction. Thus, the caregiver can sit at either lateral side of the infant care apparatus and be positioned close to that apparatus and have room for the knees by pushing the drawer out of the way. In addition, the base is configured to have generally C-shaped base members having ends that extent outwardly to provide stability for the apparatus but allow a chair to be positioned next to the infant care apparatus without hitting or being obstructed by the base.