US20050101969A1 - Vacuum extraction monitoring - Google Patents

Abstract

The invention provides technical advantages as a system, device and method that enables a fetal extraction monitor that is used to monitor fetal heart rates to also monitor a vacuum pressure in a vacuum device.

Description

RELATED APPLICATIONS
• The present invention is a divisional of and claims priority from to co-pending U.S. patent application Ser. No. 09/727,124, entitled Vacuum Extraction Monitor with Attachment For Hand Pump also by Dr. Victor Vines, filed on Nov. 30, 2000.
TECHNICAL FIELD
• The invention relates to business methods, and more specifically, the invention relates to business methods that reduce liability exposure for physicians that perform vacuum extraction deliveries.
STATEMENT OF A PROBLEM ADDRESSED BY THE INVENTION
• When operative vaginal deliveries are necessary, there are presently two options—forceps extraction, or vacuum extraction. Vacuum extraction in labor/delivery suites has become a well-accepted and commonly performed form of vaginal delivery because it may be less hazardous to the mother and fetus than forceps extraction. However, there is the potential for harm to the fetus from prolonged suction application to the fetal head. In addition, there are guidelines governing the amount of vacuum pressure that should be applied to the fetal head, as well as guidelines regarding the duration of time that the vacuum pressure is applied to the fetal head during vacuum extraction (these guidelines are printed by the manufacturers of vacuum devices, and are also available in medical literature).
• Exemplary effects of vacuum extraction on an infant during delivery include: fetal hypoxia, retinal hemorrhage, chignon, scalp marking and abrasion, cephalhematoma and subcutaneous hematoma, neonatal jaundice, intra-cranial hemorrhage, shoulder dystocia, and subgaleal hemorrhage. Subgaleal hematoma is a particularly dangerous condition. Subgaleal hematoma is formed when bleeding occurs into the potential space beneath the aponeurosis of an infant's scalp. It may be a life threatening condition for a newborn baby, and is often considered the most serious complication associated with the vacuum extraction. One danger associated with subgaleal hematoma arises because the subaponeurotic space stretches over the whole part of the cranial vault of the infant, and a large proportion of the baby's blood volume can accumulate in this space (typically, from damage to the emissary veins). Although subgaleal hematoma may occur after forceps and natural deliveries, incidents of subgaleal hematoma are increased considerably in vacuum extractions since the introduction of the vacuum device pulls the aponeurosis from the cranium and may injure the underlying veins. Furthermore, because hemorrhaging into the subgaleal space may occur slowly, and for several hours following delivery, bleeding into the subgaleal space may be difficult to initially detect.
• Accordingly, there are occasions when a fetus does poorly during or after vacuum extraction. Whether or not proper guidelines were followed during the delivery process, sometimes a legal claim is made against a doctor, hospital, nurses, and others associated with the delivery, alleging that the guidelines regarding the use of the vacuum device were not followed. The present invention provides a solution for reducing the value of a claim against those associated with a fetal delivery, and also reduces the likelihood of an erroneous claim being filed against these persons.
SELECTED OVERVIEW OF SELECTED EMBODIMENTS
• The invention provides technical advantages as a system, device and method that enables a fetal extraction monitor that is used to monitor fetal heart rates to also monitor a vacuum pressure in a vacuum device. One embodiment of the invention is a vacuum extraction monitoring system for aiding a person who is assisting with fetal extraction. The system includes a suction device that is enabled for vacuum attachment to a fetus, a pump that is capable of producing a vacuum pressure, a tubing that fluidly couples the suction device to the pump, a means for detecting a vacuum pressure coupled to the suction device, and a fetal monitor for automatically displaying a vacuum pressure, the fetal monitor being coupled to the means for detecting a vacuum pressure. In another embodiment, the invention is a method of aiding a person who is assisting with fetal extraction. The method includes attaching a suction device to a fetus by placing the vacuum device on the fetus and then inducing a vacuum pressure in the suction device, detecting the vacuum pressure, and automatically displaying the vacuum pressure on a fetal monitor.
• Of course, other features and embodiments of the invention will be apparent to those of ordinary skill in the art. After reading the specification, and the detailed description of the exemplary embodiment, these persons will recognize that similar results can be achieved in not dissimilar ways. Accordingly, the detailed description is provided as an example of the best mode of the invention, and it should be understood that the invention is not limited by the detailed description. Accordingly, the invention should be read as being limited only by the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• Various aspects of the invention, as well as an embodiment, are better understood by reference to the following EXEMPLARY EMBODIMENT OF A BEST MODE. To better understand the invention, the EXEMPLARY EMBODIMENT OF A BEST MODE should be read in conjunction with the drawings in which:
• FIG. 1 provides a block diagram of a vacuum device, illustrating systems incorporated by the invention;
• FIG. 2 provides a more detailed block schematic of a vacuum device;
• FIG. 3 provides a flowchart of a recording algorithm which illustrates one embodiment of the invention;
• FIG. 4 illustrates a block flow diagram of a vacuum device algorithm that implements one embodiment of the invention;
• FIG. 5 provides a block diagram of an adapter assembly which provides existing vacuum devices the features of the invention, and is accordingly another embodiment of the invention;
• FIG. 6 illustrates a pump attachable device capable of attachment to an electrical pump;
• FIG. 7 as a tube attachable device; and
• FIG. 8 illustrates a pump attachable device configured to attach to a hand pump, such as a KIWI hand pump.
AN EXEMPLARY EMBODIMENT OF A BEST MODE
• The invention allows physicians to measure and record the amount of pressure and the duration of pressure applied to a fetus' head during vacuum extraction, it enables improved communication between the nurse and delivering physician thus improving the safety of the vacuum assisted delivery, and the invention lowers litigation costs because a permanent record of vacuum pressures applied during delivery is created. Accordingly, the invention provides systems, devices, and methods for aiding a person who is assisting with fetal extraction. The invention is attachable to a vacuum device, and may incorporate a vacuum device. Furthermore, the pressure inside the vacuum device is monitored and recorded by a recording device.
• Preferably, the invention provides at least the features of monitoring and recording pressures in a suction device used for vacuum-based fetal extraction. Accordingly,FIG. 1 provides a block diagram of avacuum device100, illustrating systems incorporated by the invention. Apump110 which could be a manually activated hand pump, an electric pump, or any other type of air pump, is fluidly coupled to asuction device120. Thesuction device120 is attachable to a fetus, being preferably attachable to fetal head. Thesuction device120 is preferably a cup, such as a SILC, a SILASPIC, a SOFT-CUP, or a MALMSTROM-type cup, for example. Fluid coupling between thesuction device120 and thepump110 may be accomplished by atube112, and is preferably a plastic tube.
• Arecording device130, which may be a monitor, an enhanced monitor, or a custom-developed device for example, provides a user the ability to monitor air pressures and record air pressures. Accordingly, air pressures may be measured in themonitor130, or in thetube112, or in thepump110. Furthermore, inFIG. 1, acable116 couples thetube112 to themonitor130. Accordingly, in this embodiment, an air pressure is detected in thetube112 and converted into information by a device such as a transducer. Next, the detected pressure is passed as information along thecable116 to themonitor130.
• With an initial understanding of thevacuum device100, one may gain a better understanding of the invention by referring to a more detailed block schematic. Accordingly,FIG. 2 provides a more detailed block schematic of avacuum device200. Thevacuum device200 has apump110 in fluid communication with thesuction device120 through atubing112. Thetubing112, although not illustrated, may contain therein a wire for coupling thepump110 to the suction device120 (to provide a device which may support traction tension between thepump110 and the suction device120). Acoupling114 is shown dividing thetubing112. However, it should be understood that thecoupling114 need not be intrusive of thetubing112, and could be embodied as a cap/tap, for example. In any event, the coupling is enabled to detect the pressure in the tubing (whether the pressure is actually detected in thetubing112, thesuction device120, or the pump110). Preferably, thecoupling114 is a plastic tube with a transducer therein. Although not shown inFIG. 2, a transducer in the coupling detects a pressure, and then produces a mechanical or electrical signal based on the pressure detected, or other transportable signal based on the detected pressure (such as a wireless radio frequency communication).
• Thecable116 provides a commutative connection between thecoupling114 and apressure gauge132 located in therecording device130. Of course, although thepressure gauge132 is illustrated as being located in therecording device130, thepressure gauge132 could in fact be located in thecoupling114, or along thecable116. Thus, thepressure gauge132 functions as a mechanical or electrical signal receiver, which translates a mechanical signal, or electrical signal, or a wireless signal into data that is associated with a pressure.
• Aprocessor140 was coupled to thepressure gauge132, and provides a means for processing data from thepressure gauge132 and associating that data with various tables, algorithms, and other information. Furthermore,processor140 may drive other systems such as adisplay136, aprinting device138,warning system144, or asafety system142, or send information to arecording device134. Preferably, the processor is a digital signal processor (DSP), a Pentium processor, or a Strong Arm processor, for example. Theprocessor140 retrieves various tables, algorithms, and other information from therecording device134, that preferably stores an electronic record. Preferably, therecording device134 is embodied as memory, such as RAM, ROM, or removable memory such as Flash RAM, a Memory Stick, or a CD ROM.
• Thedisplay136 provides real time information, such as pressures over time, dangerous conditions detected (or other information) to persons assisting with the extraction of the fetus. Preferably, thedisplay136 is a cathode ray video screen, or a plasma screen.
• Theprinting device138 provides the ability to print numbers or graphs indicating a pressure over time, progressive pressures detected over time. Preferably, theprinting device138 generates these prints on paper. Furthermore, although illustrated as being integrated into therecording device130, it should be understood that theprinting device138 may be located externally from therecording device130.
• Thesafety system142 causes the implementation of a safety pressure release valve preferably located on thepump110. When triggered, thesafety system142 may release some of the pressure, or all of the pressure thus returning the pressure inside thetubing112 to the local atmospheric pressure (or room pressure). Thesafety system142 may be embodied as software algorithm for execution in memory, or as mechanical device.
• Thewarning system144 is for producing a warning when a predetermined pressure or pressures are detected. Typically, the predetermined pressure will be a vacuum pressure, which is lower than a predetermined vacuum pressure, such as 0.2 kgms/cm²-0.8 kgms/cm², depending on the stage of delivery. The warning may be embodied as a light, a sound, or a voice, for example. A light may flash at different rates, or present different colors, or present different intensities as pressure changes in the tube. Similarly, a sound may change in tone as different pressures are detected, or a voice may verbally indicate a pressure or a warning condition. Furthermore, the warning system may be used to trigger and provide information to thesafety system142.
• A better understanding of the invention may be achieved by examining the operation of the invention.FIG. 3 provides a flowchart of arecording algorithm300. First, in arecord pressure act310, therecording algorithm300 records a pressure, which exists in a vacuum device. Then, in a store recordedpressure act320, therecording algorithm300 creates a permanent record of the pressure which was recorded in therecord pressure act310.
• An even better understanding of the invention may be realized by examining the processes flow of a vacuum device embodied according to the invention. Accordingly,FIG. 4 illustrates a block flow diagram of avacuum device algorithm400 that implements one embodiment of the invention. Thevacuum device algorithm400 comprises apump algorithm402 for illustrating acts performed with a vacuum device pump, and amonitor algorithm405 illustrating acts associated with a recording device. Thevacuum device algorithm400 begins in apump algorithm402.
• Thepump algorithm402 is initiated in an engagemonitor act410. The engage monitor act may include attaching a cable between a vacuum pump and a recording device, and then turning on the recording device. After the engagemonitor act410, thepump algorithm402 proceeds to an applysuction device act415 in which a suction device is attached to a fetus, and preferably a fetal head. It should be noted that in the applysuction device act415, if a disposable MITYVAC is being used in the procedure, adapters should be attached to suction tubing of the vacuum device and the disposable MITYVAC assembly. Prior to applying the suction device to the fetus, the applysuction device act415 calibrates, or zeros, the monitor so that the pressure detected prior to applying a vacuum to the fetus is recognized as being the local atmospheric pressure. Likewise, prior to the application of a vacuum to a fetus, the monitor is initialized, or “zeroed,” to local atmospheric conditions.
• Following the applysuction device act415, thepump algorithm402 proceeds to an initiatevacuum act420. In the initiate vacuum act420 a vacuum pressure is created in the vacuum device by manually actuating a manual pump, or by engaging the vacuum switch or trigger in an electric pump. The next act in thepump algorithm402 changes the vacuum pressure. This is accomplished in an altervacuum pressure act425, and is typically employed as a result of a response received from themonitor algorithm405. Of course, altering the vacuum pressure may not be necessary during a vacuum extraction procedure, and thus the altervacuum pressure act425 should especially be viewed as an optional act for the present embodiment (although the only needed acts are explicitly articulated in the claims).
• Next, adisengage vacuum act430 is performed when the pressure in the vacuum device is returned to at least local atmospheric pressure. Furthermore, the pressure may be raised to a pressure greater than local atmospheric pressure to encourage the suction device to separate from the fetus. Then, thevacuum device algorithm400 andpump algorithm402 end together in a removesuction device act435, in which the suction device is removed from the fetus. Furthermore, in the removesuction device act435 the recording device may be disengaged, and the record of the pressures detected during thevacuum device algorithm400 may be stored in a permanent medical record, which may be a physical paper record and/or an electronic record.
• Themonitor algorithm405 initiates in a detectpressure act450, which begins in response to the initialization of the recording device in the engagemonitor act410. In the detect pressure act450 a pressure in the vacuum device is detected, which will typically be between a room (or atmospheric) pressure and vacuum pressure (meaning a pressure lower than the local atmospheric pressures). Next, thevacuum device algorithm400 continues to arecord pressure act455. In therecord pressure act455 the pressure detected in the detectpressure act450 is automatically recorded (or stored), preferably by an electronic means (such as a memory) or by a paper means. Furthermore, therecord pressure act455 may include the displaying of the recorded pressure on a monitor or other display.
• The recorded pressures are monitored and processed in a process recordedpressure act460. The process recordedpressure act460 evaluates the detected pressure in a warning system, and may direct the displaying or printing of additional information in response to the warning system. [The process-recordedpressure460 may include a sub-act of displaying the processed information on the display device, such as a monitor.] Likewise, if the process is recorded at460 determines if the detected pressure exceeds a predetermined pressure, the process recordedpressure act460 may direct a pressure change, such as a lower pressure, or an immediate return to local atmospheric pressure, in a directpressure change act465. The directpressure change act465 produces the electrical or mechanical signals needed to implement the alter-vacuum pressure act425.
• The invention provides the ability to accurately measure, record, and trace pressure events that transpire in a vacuum device during vacuum extraction. Accordingly, the invention assist physicians, hospitals, and other delivery personnel in the defense of accusation that proper guidelines were not followed during the vacuum extraction. Furthermore, those who suffer from improper vacuum extraction also have access to a permanent medical record, which should facilitate mediated settlements, and avoid the costs of lengthy discovery and emotionally scaring litigation. Also, because data will be collected with each vacuum extraction, the guidelines for the conduct of a vacuum extraction may be changed and improved to more accurately be able to predict safe guidelines for a vacuum extraction delivery.
• It will sometimes be advantageous to provide existing vacuum devices the ability to access the advantages provided by the invention.FIG. 5 provides a block diagram of anadapter assembly500, which provides existing vacuum devices access to advantages of the invention, and is accordingly another embodiment of the invention. Theadapter assembly500 comprises apump510 fluidly coupled to asuction device520 by atubing525. Adisplay device530 is connected to thepump510. Preferably, thedisplay device530 is coupled to thepump510 via an adapter to thepump510. Better understanding of theadapter assembly500 may be achieved by examining specific embodiment.
• FIG. 6 illustrates a pumpattachable device600 capable of attachment to anelectrical pump655. The pumpattachable device600 has anadapter610, such as the threaded fittings illustrated inFIG. 6. Furthermore, the pumpattachable device600 has apressure transducer620, which detects a pressure and converts the detected pressure to a mechanical or electrical signal capable of being transferred to a monitor (not shown) via acable630. Thecable630 includes aplug635 capable of attachment to a monitor or other recording device.
• Also, illustrated inFIG. 6 is apump system650 having a pump attachable device attached thereto. Thepump system650 includes anelectric pump655 such as a MITYVAC, or disposable MTFYVAC, for example. Theelectric pump655 has afront end665, which has a cavity for supporting other devices and for transporting the pressures, including the vacuum pressure, created by theelectric pump655.
• Thefront end665 has thereon apressure gauge receiver660. Typically, thepressure gauge receiver660 accepts a pressure gauge that mechanically detects a pressure, which is then displayed for those performing the vacuum procedures. In operation of one embodiment of the invention, the pressure gauge is removed from the electric pump, typically by unscrewing the pressure gauge, and the pumpattachable device600 is then inserted into thepressure gauge receiver660. Also provided by thefront end665 is apressure release valve670. Thepressure release valve670 allows the inflow of air into the front end, and particularly into the cavity of the front end, in order to increase the pressure in the vacuum device.
• Another embodiment of the invention is illustrated inFIG. 7 as a tubeattachable device700. The tubeattachable device700 includes afirst end705, and asecond end707. Thefirst end705 is preferably configured to either attach to a plastic tube section, or a suction device. Thesecond end707 is preferably configured to attach to a tube, or a front end such as thefront end765 that is adapted to receive thesecond end707. The tubeattachable device700 includestubing740, which is preferably plastic tubing.
• Thetubing740 includes apressure gauge receiver760. Accordingly, a transducer/pressure gauge720 is inserted into thetubing740 and secured in the tubing by anadapter710. Furthermore, pressures detected by thepressure transducer720 are converted into a data signal that is sent to a recording device along acable730. Thecable730 also includes aplug735, which is connectable to therecording device monitor780, or to asecond plug737. Theplug737 couples anextension cord738 to asecond plug739. Thesecond plug739 is also attachable to therecording device780 at aplug socket788.
• The vacuum device illustrated inFIG. 7 includes apump755, which provides a disposable MITYVAC, and apressure gauge760, which is fitted into thefront end765. Thus, the vacuum device provides a physician the advantage of having a mechanical visual display provided by the gauge760 (thus requiring little change by those who are accustom to viewing the mechanical gate760), as well as providing mechanical and electric displays and printouts of the recorded pressures while therecording device780.
• Therecording device780 may produce a printed-paper record782, as well as avisual display784. Of course, the printed-paper record782 or thevisual display784 may print or display numbers, graphical representation or other indicia of the pressures being detected in the vacuum device. Furthermore, therecording device780 provides awarning device786 which could produce a light, sound, or a vocalized recording of a warning to those assisting with the fetal extraction.
• FIG. 8 illustrates a pumpattachable device800 configured to attach to ahand pump855, such as a KIWI hand pump. The pumpattachable device800 includes anadapter810, such as threading, gaskets, or other attachments capable of forming a fluid-tight seal, a pressure-recording device820, such as a transducer, and acable830 for communicating a detected pressure to a recording device via aplug835. Thehand pump855 includes ahandle857, which maintains avacuum cavity865 therein. Thevacuum cavity865 is fluidly connected to ahose870 and asuction device872. Thehandle857 also includes apressure gauge receiver860. In an unmodified hand pump, the pressure gauge receive860 accepts a mechanical pressure gauge that mechanically indicate a detected pressure in thevacuum cavity865. In the vacuum device according to the present embodiment of the invention, the pumpattachable device800 is secured into thehandle857 of thehand pump855 via thepressure gauge860.
• Thus, though the invention has been described with respect to a specific preferred embodiment, many variations and modifications will become apparent to those skilled in the art upon reading the present application. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the prior art to include all such variations and modifications.

Claims (13)

1. A device for recording a pressure produced by a vacuum extraction device, the vacuum extraction device enabled to couple to a fetus via a suction device, comprising:

a cable that is attachable to a monitor, the monitor capable of recording a detected pressure;

a pressure detection device coupled to the cable, the pressure detection device couples to a cavity of a vacuum extraction device for use with fetal extraction such that the pressure detection device may detect a pressure in the cavity;

the pressure detection device further adapted to communicate a detected vacuum pressure to the monitor via the cable;

the vacuum extraction device being adapted to produce a vacuum therein via hand-actuation; and

the vacuum extraction device comprising a suction device being vacuum attachable to a scalp portion of a fetus.

2. The device ofclaim 1 wherein the tubing has a first end and a second end.

3. The device ofclaim 2 wherein the first end and the second end are enabled to couple to tubing.

4. The device ofclaim 2 wherein the first end is enabled to attach to a vacuum pump.

5. The device ofclaim 2 wherein the first end is enabled to attach to a suction device.

6. A vacuum extraction pump-attachable device that monitors a vacuum pressure in a vacuum extraction device, comprising:

an adaptor enabled to attach to a pressure gauge receiver of a hand actuated vacuum extraction device, the vacuum extraction device comprising a suction device adapted to couple to a scalp portion of a fetus;

a vacuum pressure detector secured in the adapter such that the vacuum pressure detector is exposed to an air cavity in the vacuum extraction device; and

a cable coupled to the vacuum pressure detector, the cable enabled to attach to a monitor for recording a detected vacuum pressure.

7. The pump-attachable device ofclaim 6 wherein the air pressure detector is a transducer.

8. The pump-attachable device ofclaim 6 wherein the monitor is coupled to the cable.

9. The pump-attachable device ofclaim 8 wherein the monitor is enabled to display a detected pressure.

10. The pump-attachable device ofclaim 6 wherein the air pressure detector generates a mechanical signal based on the pressure.

11. The pump-attachable device ofclaim 6 wherein the air pressure detector generates an electrical signal based on the pressure.

12. The pump-attachable device ofclaim 8 wherein the monitor is enabled to generate a paper record.

13. The pump-attachable device ofclaim 6 further comprising a pressure release valve coupled to the hand pump.

Images