JP7212805B2 - Methods and devices for monitoring blood - Google Patents

Description

[0001] The present disclosure relates generally to blood monitoring equipment used, for example, during cardiac surgery.

[0002] During surgery, a patient's venous system is sometimes connected to an extracorporeal circuit that temporarily replaces the function of the heart and lungs. An extracorporeal blood circuit (ECC) may include, among other features, a pump to replace heart function and an oxygen delivery device to replace lung function.

The present disclosure relates to blood monitoring apparatus, methods and devices that may be used as part of an extracorporeal blood circuit.

[0003] In Example 1, an apparatus includes a cuvette including a cuvette body forming a substantially flat outer surface and having a sensor window defined within the substantially flat outer surface. The cuvette further includes a probe retaining structure extending from the cuvette body. The device includes a probe having a probe body and a protrusion removably coupled to the probe retaining structure.

[0004] In Example 2, the apparatus of Example 1, wherein the projection is coupled to a spring-loaded assembly positioned at least partially within the probe body.
[0005] In Example 3, the apparatus of any of Examples 1-2, wherein the cuvette further comprises at least one pin extending from the cuvette body, the at least one pin mechanically coupled to the probe. be done.

[0006]In Example 4, the apparatus of any of Examples 1-3, wherein the probe further includes a sensor positioned in alignment with the sensor window.
[0007] In Example 5, the apparatus of Example 4, wherein the sensor comprises an optical sensor.

[0008] In Example 6, the apparatus of any of Examples 1-5, wherein the probe retaining structure forms a recess and at least a portion of the protrusion extends therein.
[0009] In Example 7, the apparatus of any of Examples 1-6, wherein the probe retaining structure forms a hole and at least a portion of the protrusion extends therein.

[0010] In Example 8, in the apparatus of Example 1, the protrusion is integrally formed with the probe body.
[0011]In Example 9, in the apparatus of any of Examples 1-8, the probe holding structure is flexible.

[0012] In Example 10, in the apparatus of any of Examples 1-9, the protrusion is deformable.
[0013] In Example 11, the cuvette includes a cuvette body including a sensor window frame, a sensor window positioned in the sensor window frame, and a window retainer that mechanically couples the sensor window to the cuvette body.

[0014] In Example 12, the cuvette of Example 11, wherein the cuvette body forms at least two teeth that are mechanically coupled to the window retainer.
[0015] In Example 13, the cuvette of any of Examples 11-12 further comprises an o-ring positioned between the sensor window and the sensor window frame.

[0016] In Example 14, the cuvette of any of Examples 11-13, wherein the sensor window includes a fluorescent coating.
[0017] In Example 15, the cuvette of any of Examples 11-14, wherein the sensor window comprises polyvinylidene fluoride.

[0018] In Example 16, the cuvette of any of Examples 11-15, wherein the sensor window has a biocompatible film coating on the surface facing the central bore formed by the cuvette body.

[0019] In Example 17, the cuvette of any of Examples 1-16, wherein the cuvette body includes a substantially planar outer surface and the single sensor window frame is defined in the substantially planar surface ing.

[0020] In Example 18, the cuvette of any of Examples 1-17, wherein the probe retaining structure is positioned near the end of the cuvette body.
[0021] In Example 19, the cuvette of Example 18, wherein the probe holding structure comprises a hole.

[0022] In Example 20, an apparatus includes a cuvette including a cuvette body having a first cuvette end and a second cuvette end. The cuvette further includes a window frame positioned between the first and second cuvette ends, a window positioned within the window frame, a first probe retaining structure positioned near the first cuvette end, and A second probe retaining structure extends from the cuvette body and is positioned near the second cuvette end. The device further includes a probe having a probe body, a first probe end, and a second probe end. The probe further includes a first cuvette engaging structure near the first probe end capable of engaging the first probe retaining structure and a second probe near the second probe end. A second cuvette engaging structure is removably engageable with the retaining structure.

[0023] In Example 21, the apparatus of Example 20 includes a first probe-retaining structure comprising at least one pin, a second probe-retaining structure comprising at least one hole, and a first probe-retaining structure comprising at least one bearing surface. and a second cuvette engaging structure comprising at least one protrusion.

[0024] While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.

[0025] Fig. 2 is a schematic illustration of a blood monitor according to certain embodiments of the present disclosure; [0026] Fig. 3 is an exploded perspective view of a cuvette according to certain embodiments of the present disclosure; [0027] Fig. 3 is a cross-sectional perspective view of a cuvette according to certain embodiments of the present disclosure; [0028] Fig. 3 is a perspective view of a cuvette according to certain embodiments of the present disclosure; [0029] Fig. 4 is a cross-sectional perspective view of a cuvette according to certain embodiments of the present disclosure; [0030] Fig. 3 is a perspective view of a cuvette and probe according to certain embodiments of the present disclosure; [0031] Fig. 4 is a partial cross-sectional view of a cuvette and probe assembly according to certain embodiments of the present disclosure; [0032] Fig. 4 is a partial cross-sectional view of a cuvette and probe assembly according to certain embodiments of the present disclosure;

[0033] While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail below. The intention, however, is not to limit the invention to particular described embodiments. Rather, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.

[0034] Figure 1 is a schematic diagram of a blood monitor 100 incorporated into an extracorporeal blood circuit (ECC). During surgery, the patient's blood can be directed through the ECC, which receives the blood and returns the blood and other fluids to the patient, among other equipment, such as a heart-lung machine, an oxygenator, a heart-lung machine, an oxygenator, and a reservoir (not shown in FIG. 1). The ECC may also include blood monitoring equipment for measuring one or more parameters or properties of blood at one or more locations within the ECC. A blood monitoring instrument may include a cuvette (ie, container) 102 through which blood flows, a probe 104 coupled to the cuvette, and a monitor 106 in communication with the probe. A first cuvette/probe assembly can be positioned in the arterial blood line (e.g., to measure oxygenated blood parameters before being returned to the patient) and a second cuvette/probe assembly (e.g., It can be positioned in the venous blood line) to measure venous blood parameters prior to treatment with ECC. Cuvette 102 is a single-use cuvette and is discarded after being used once. As will be described in more detail below, the probe 104 for providing blood parameter signals may be reusable (e.g., attachable to and detachable from the cuvette 102 so that the probe can be reused). may be used).

[0035] Blood monitoring devices may include various sensing elements for measuring characteristics of venous and/or arterial blood. In some embodiments, it may be desirable for the blood monitoring device to measure hematocrit, oxygen saturation, and temperature, among other parameters of venous blood. Such measurements can be made using a variety of sensor types, electronic, chemical, optical, and the like. For example, hematocrit measurements can be performed by utilizing LEDs that emit a range or set of wavelengths of light into the blood. Blood scatters the emitted light and the scattering characteristics are sensed by an optical sensor and can be used to provide a signal from which the hematocrit level of the blood can be determined. Oxygen saturation can also be measured using an optical sensor. Blood temperature can be measured using an infrared sensor, which can measure temperature without contacting the blood. In some embodiments, it may be desirable to measure oxygen tension and temperature, among other parameters of arterial blood. Measurement of oxygen partial pressure can be performed using fluorescence or oxygen quenching, as described in more detail below. As with venous blood, the temperature of arterial blood can be measured using an infrared sensor. It should be understood that sensors providing a wide variety of both signal type (eg, electronic, optical) and construction may be used in embodiments of the present disclosure.

[0036] Referring again to FIG. 1, the probe 104 may communicate with and direct measurements to a monitor 106, which may be integrated into a heart-lung machine (HLM) 108; Or it may be integrated into a standalone device that can be coupled to a machine such as a heart-lung machine. The HLM 108 is shown schematically between the patient and the cuvette 102 and probe 104, but as described in more detail herein, the probe and cuvette include positions between the HLM 108 and the patient. , may be placed at various locations along the blood circuit. For example, one cuvette 102 and probe 104 may be placed in the venous blood line to measure properties of venous blood, and a second cuvette and probe placed in the arterial line to measure properties of arterial blood. may be taken.

[0037] In one embodiment, monitor 106 can display measurements obtained from various sensors associated with one or more cuvette/probe assemblies. Monitor 106 may also display measurements from other monitoring devices. For example, monitor 106 may display patient, surgical, and blood measurements and calculated parameters such as temperature, hematocrit, hemoglobin, oxygen delivery, carbon dioxide production, body surface area, and ventilation, among others.

[0038] FIG. 2A shows an exploded view of a cuvette 200 having a cuvette body 202, a sensor window 204, a window retainer 206, and an O-ring 208. FIG. The cuvette body 202 has a hollow inner portion with a first end 210 and a second end 212 to allow blood to flow through the central bore of the cuvette. The outer surface of the cuvette body 202 is generally cylindrical, but includes flat or substantially flat surfaces on portions of the body to which probes may be coupled. Cuvette body 202 defines at least one sensor window, such as a single sensor window frame 214 in the form of a hole in a portion of the cuvette body. When assembled, the sensor window 204 is positioned within a single window frame 214 to prevent blood from leaking or flowing through the holes while providing visual and/or visual protection for blood within the central bore of the cuvette. Or allow access by sensors.

[0039] In one embodiment, window 204 may be made from an optically transparent polymer such as polyvinylidene fluoride (PVDF) and may be coated with a fluorescent coating or paint. The fluorescent coating can be of the type that is sensitive to the partial pressure of oxygen in the blood, such that the paint changes color or shade as the partial pressure of oxygen changes. In some embodiments, the entire window may be made from an optically transparent, biocompatible polymer and may not require additional coatings for biocompatibility. Although the window 204 and window frame 214 of FIG. 2A have a circular shape, it will be appreciated that other shapes may readily be employed. In one embodiment, the cuvette 200 of FIGS. 2A and 2B may be used as an arterial line cuvette.

[0040] The window 204 is secured to the cuvette body 202 by a retainer 206, as shown in FIG. 2B, which is a cross-sectional view of the assembled cuvette of FIG. Window 204 is shown as having a thickness that extends into the aperture of window frame 214 . In some embodiments, a sealing element such as O-ring 208 is positioned on a surface of window frame 214 that extends radially from the central portion of the window. O-ring 208 seals window frame 214 to prevent blood from leaking through the frame.

[0041] The window retainer 206 shown in Figure 2A is U-shaped and defines various holes. A circular hole 216 formed in a surface 218 of window retainer 206 is configured to align with window 204 to allow light and/or sensor access to the blood in the cuvette. Holes 216 are shown as circular in shape, but other shapes are contemplated by applicant. Legs 220 extend generally perpendicular to surface 218 and form holes 222 , 224 that assist in coupling retainer 206 to cuvette body 202 .

[0042] Figure 2B shows a set of teeth 226-232 that, when assembled, are configured to engage window retainer holes 222, 224 to join window retainer 206 and cuvette body 202. It is shown. First teeth 226 , 228 are positioned on opposite sides of cuvette body 202 . These tines extend directly from the cuvette body 202 and are shown as triangular shaped protruding from the body, although it will be appreciated that other shapes may readily be employed. Also extending from the body are one or more L-shaped or U-shaped components 234 , 235 that project toward the cuvette body 202 and are also triangular in shape. teeth 230, 232, other shapes may be used. As shown in FIG. 2B, window retainer 206 is configured such that teeth extend into retainer holes 222, 224 to secure retainer 206 (and window 204 and O-ring 208) to cuvette body 202. , it slides on teeth 226-232. Retainer 206 may be formed from a variety of suitable materials such as metal or plastic.

[0043] Referring again to FIG. 2A, a first probe retaining structure, such as a pin 236, shown extending from the cuvette body 202, on each side of the body near the inlet 210, holds the probe. may be provided to help mechanically couple the to the cuvette. A second probe retaining structure, such as a flange 238 , also extends from the body and can also assist in mechanically coupling the probe to the cuvette 200 . A flange 238 extends radially from the tubular portion of the cuvette body near outlet 212 . A first probe retaining structure (e.g., pin 236) is described as being positioned near inlet 210, and a second probe retaining structure (e.g., flange 238) is positioned near outlet 212. Although described as one, the position of the probe holding structure can be reversed or changed. In the embodiment of FIG. 2A, the second probe retaining structure includes a hole 240 or similar feature into which a portion of the probe extends to mechanically couple the probe to the cuvette 200. may assist the As will be described in more detail below, the first and second probe retaining structures 236 and 238 prevent air from developing between the cuvette and the probe when the probe is coupled to the cuvette 200 and They are positioned relative to each other so as not to interfere with blood parameter measurements.

[0044] FIG. 3A shows a perspective view of cuvette 300, and FIG. 3B shows a cross-sectional perspective view of cuvette 300. FIG. The cuvette 300 shown in Figures 3A and 3B may be suitable for use as an intravenous cuvette. Cuvette 300 has a cuvette body 302 with a hollow inner portion having a first end 304 and a second end 306 to allow blood to flow through the central bore of the cuvette. The outer surface of the cuvette body 308 is primarily cylindrical, but includes a flat or substantially flat surface 310 on the portion of the body on which the probe can be placed. As shown in FIG. 3B, the inner portion includes a plane 312 substantially parallel to plane 310 . Since cuvettes in the venous blood circuit may not need to measure partial pressure of oxygen, in some embodiments cuvette 300 includes windows and window frames as featured in FIGS. 2A and 2B. Not characterized. Cuvette 300 includes first probe retaining structure, such as retaining pins 314 extending from cuvette body 302 on opposite sides. Pins 314 help mechanically couple the probe to the cuvette. Also extending from the body is a second probe retaining structure, such as a flange 316 extending from a portion of the cuvette body 302 . Flange 316 defines a hole 318 or similar feature into which a portion of the probe may extend to help mechanically couple the venous probe to cuvette 300, for example.

[0045] FIG. 4 shows cuvette 400 and probe 402 with probe body 404 partially coupled. Cuvette 400 includes a first probe retaining structure with pins 406 that mechanically couple cuvette 400 to first cuvette engaging structure 416 of probe 402 . First cuvette-engaging structure 416 may include a bearing surface 414 that allows probe 402 to pivotally contact a first probe-retaining structure (eg, pin 406 ) on cuvette 400 . can be provided with a portion of the U-shaped channel shown in FIG. Cuvette 400 also includes a second retaining structure including a flange 408 extending from cuvette 400 . Flange 408 may include holes, recesses, etc. for receiving a second cuvette engaging structure such as bosses or protrusions 410 extending from probe 402 . First and second probe retaining structures 406 and 408 help mechanically couple cuvette 400 to corresponding first and second cuvette engaging structures 416 and 410 on probe 402 .

[0046] Probe 402 may include the various sensors, components, and associated circuitry described above for monitoring blood. For example, probe 402 may include one or more of LEDs, optical sensors, and infrared sensors. In some embodiments, the probe includes an optical sensor that detects the color change of a window coupled to the cuvette 400 and covered with a fluorescent coating or paint, the fluorescent coating or paint reacting to blood oxygen partial pressure. It is sensitive and can change color or shade in response to changes in oxygen partial pressure. Probe 402 includes communication port 412 that allows communicative coupling (eg, electrically or by wireless connection) between probe 402 and, for example, a monitor and/or processing equipment.

[0047] Figure 5 shows a partial cross-sectional view of a cuvette 500 and a probe 502 coupled together. The cuvette 500 is part of a first probe-retaining structure, which can include a set of pins 506 extending from the cuvette 500, and a second cuvette-engaging structure (e.g., bosses or protrusions 510) of the probe. and a second probe retaining structure (eg, flange 504) that includes a hole 508 extending therein. Although protrusion 510 is shown as a spherical shape partially positioned within probe 502, it will be appreciated that other shapes may be used. Protrusion 510 is coupled to a spring assembly 512 positioned within probe 502 and spring assembly 512 protrudes to engage a second retention structure on cuvette 500 (eg, hole 508 in flange 504). It is configured to provide a spring force against the protrusion 510 to bias the portion.

[0048] The first cuvette engaging structure 518 includes a bearing surface 514 that allows the probe to engage a first probe retaining structure (eg, pin 506) on the cuvette 500. As shown in FIG. As probe 502 pivots on bearing surface 514 about pin 506 , protrusion 510 contacts portion 516 of second probe retaining structure 504 such that protrusion 510 is at least partially retracted within probe 502 . causes the spring assembly 512 to compress. Once protrusion 510 is aligned with hole 508 , spring assembly 512 is uncompressed, urging protrusion 510 into hole 508 to couple cuvette 500 and probe 502 . In other embodiments, the second probe retaining structure (e.g., flange 504) on cuvette 500 is not a hole to facilitate engagement with the second cuvette engaging structure on probe 502. Other features such as dimples may be provided. Spring assembly 512 provides sufficient spring force to maintain the coupling between probe 502 and cuvette 500 when engaged, but also allows probe 502 to disengage if desired. . The probe 502 and its features, the first probe-retaining structure (e.g., pin 506) and its features, and the second probe-retaining structure (e.g., flange 504) are aligned when the probe 502 is coupled to the cuvette 500. , are positioned with respect to each other such that air, which could render the blood parameter measurements inaccurate, does not interfere with the blood parameter measurements.

[0049] Figure 6 shows a cuvette 600 and a probe 602 coupled together. Cuvette 600 includes a first probe retaining structure comprising a set of pins 606 and a second probe retaining structure including flange 604 extending from cuvette 600 . The second probe retaining structure 604 includes a hole 608 into which a portion of the second cuvette engaging structure of the probe extends. The second cuvette engaging structure is depicted in FIG. 6 as a boss or protrusion 610, although other structures may be employed. A first cuvette engaging structure 616 including a bearing surface 612 is provided on the probe 602 to pivot to the pin 606 comprising the cuvette first probe retaining structure to assist in coupling the cuvette 600 and the probe 602 together. movably engage. Protrusions 610 shown in FIG. 6 are not coupled to the spring assembly and therefore may not be designed to move in and out of probe 602 . In certain embodiments, probe 602 may be coupled to cuvette 600 by pivoting probe 602 against pin 606 of the cuvette with bearing surface 612 until protrusion 610 engages hole 608 . . In the embodiment of FIG. 6, the second probe retaining structure 604 is such that when the projection 610 contacts a portion 614 of the second probe retaining structure, an applied force is applied to the second probe retaining structure 604 . to allow protrusion 610 to enter hole 608 . As shown in FIG. 6, a portion 614 of the second probe retaining structure 604 provides a camming action against the second cuvette engaging structure (eg, protrusion 610) of the probe to move towards the hole 608. An angled surface is included to assist in sliding protrusion 610 along portion 614 . In some embodiments, the boss or protrusion 610 itself (or at least a portion of the boss or protrusion) is flexible such that the boss or protrusion moves along the retention structure toward the hole 608. It may be temporarily deformed. When deformable boss or protrusion 610 is aligned with hole 608 , protrusion 610 returns to its original shape and extends at least partially into hole 608 to mechanically connect cuvette 600 and probe 602 . can be bound to In some embodiments, the cuvette may include bosses, protrusions, or similar structures that extend into depressions, holes, or similar features formed by the probes. Similar to the embodiments described above, the cuvette's second probe-retaining structure (eg, flange 604) allows the probe's second cuvette-engaging structure (eg, protrusion 610) to slide into a recess or hole into the cuvette. It may have a flexibility that allows the structure to bend when the probes are bonded together. Alternatively, or in addition, a portion of the probe may be flexible to allow the boss or protrusion to slide and then extend into the recess or hole.

[0050] Various modifications and additions may be made to the exemplary embodiments discussed without departing from the scope of the invention. For example, although the above-described embodiments refer to particular features, the scope of the invention does not include embodiments having different combinations of features, and all of the described features. It also includes embodiments that do not. Accordingly, the scope of the invention is intended to embrace all such alternatives, modifications and variations as falling within the scope of the claims along with their equivalents.

Claims (13)

A blood monitoring device comprising a cuvette and a probe,
The cuvette includes a cuvette body having a substantially planar outer surface on a portion of the cuvette body, the cuvette body having a sensor window defined within the substantially planar outer surface. ,
the cuvette includes a first probe retaining structure extending from the cuvette body and a second probe retaining structure extending from the cuvette body;
The probe includes a probe body, wherein the probe body is removably coupled to a first cuvette-engaging structure that engages the first probe-retaining structure and the second probe-retaining structure. and a protrusion that
The first probe retaining structure includes a first pin extending outwardly from a first side of the cuvette body in a first direction and a pin extending outwardly from a second side of the cuvette body in a second direction. a second pin extending, wherein the second side is opposite the first side;
The first cuvette-engaging structure includes a bearing surface configured to engage the first pin and the second pin, and the probe body extends over the first pin on the bearing surface. A blood monitor that pivots about a pin and said second pin . 2. The blood monitor of Claim 1 , wherein the bearing surface comprises a portion of a U-shaped channel extending from the probe body. 3. The blood monitor of Claim 2 , wherein the cuvette body is disposed within the U-shaped channel. 2. The blood of claim 1, wherein the first probe-retaining structure is positioned near the inlet of the cuvette body and the second probe-retaining structure is positioned near the outlet of the cuvette body. surveillance equipment. 2. The blood monitor of claim 1, wherein the projection is coupled to a spring assembly positioned at least partially within the probe body. The projection includes a spherical portion positioned at least partially within the probe body, the spring assembly biasing the spherical portion outwardly relative to the probe body, the spring assembly comprising: 6. The blood monitor of claim 5 , wherein said bulb is compressible to allow it to retract at least partially within said probe body. 3. The blood monitor of Claim 1, wherein the projection is deformable. 2. The blood monitor of claim 1, wherein the second probe retaining structure is a flange extending radially outwardly from the cuvette body. 2. The blood monitor of Claim 1, wherein the second probe retaining structure forms a recess or hole, and at least a portion of the projection extends into the recess or hole. 2. The blood monitor of claim 1, wherein said second probe retaining structure is flexible. 2. The blood monitor of claim 1, wherein said probe includes an optical sensor aligned with said sensor window. 12. The blood monitor of Claim 11 , wherein the sensor window has a biocompatible film coating on the surface facing the central bore formed by the cuvette body. 13. The blood monitor of claim 12 , wherein said biocompatible film coating is a fluorescent coating.

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