DEVICE FOR EVACUATING AND/OR MONITORING GAS LEAKING FROM A PATIENT DURING SURGERY OR ANESTHETIZATION

Abstract

A system is described herein for evacuating gas as it is leaking from a patient's airway. The system comprises a gas evacuation flowpath configured for collecting a gas flow escaping from the patient when inserted into the patient's airway. A vacuum source is connected to the gas evacuation flowpath. Devices that may be employed as part of the system and a method for evacuating gas from a patient are also described.

Claims

1.-30. (canceled)

31. A method for evacuating gas as it is leaking from a patient's airway, the method comprising: collecting a gas that has leaked past a seal of closed circuit gas administration equipment and into the patient's throat or mouth; and removing the collected gas from the patient using a vacuum system.

32. The method of claim 31, wherein the seal is a primary seal, the method further comprising providing a secondary seal in the patient's airway that is separate from the primary seal, the collecting of the gas occurring between the primary seal and the secondary seal.

33. The method of claim 32, further comprising administering a gas to a patient using the airway tube, the patient airway tube including the primary seal.

34. The method of claim 33, wherein the gas comprises anesthesia.

35. The method of claim 33, further comprising determining one of oxygen concentration, anesthesia concentration or CO.sub.2 gas concentration in the collected gas.

36. The method of claim 31, further comprising determining one of oxygen concentration, anesthesia concentration or CO.sub.2 gas concentration in the collected gas.

37. The method of claim 36, further comprising determining the effectiveness of the primary seal using the determined concentration of the collected gas.

38. The method of claim 36, further comprising providing determined oxygen concentration data to a user.

39. The method of claim 31, further comprising determining if there is acid reflux in the patient's airway.

40. The method of claim 31, wherein the closed circuit gas administration equipment comprises an intubation device comprising an airway tube and the seal positioned on an outer perimeter of the airway tube, the airway tube comprising a first flowpath configured to administer a gas to the patient, the seal positioned in the patient's airway to block a space between the airway tube and tissue lining the patient's airway.

41. The method of claim 40, wherein the closed circuit gas administration equipment further comprises a gas evacuation flowpath comprising one or more vents positioned in the patient's airway for collecting the gas that has leaked past the seal, the gas evacuation flowpath being separate from the first flowpath.

42. The method of claim 41, wherein the seal is a primary seal, and further comprising providing a secondary seal in the patient's airway that is separate from the primary seal, the one or more vents being positioned between the primary seal and the secondary seal.

43. A method for evacuating gas as it is leaking from a patient's airway, the method comprising: inserting an intubation device comprising an airway tube and a primary seal positioned on an outer perimeter of the airway tube, the airway tube comprising a first flowpath configured to administer a gas to the patient, the primary seal positioned in the patient's airway to block a space between the airway tube and tissue lining the patient's airway; inserting a gas evacuation flowpath comprising one or more vents into the patient, and providing a secondary seal in the patient's airway that is separate from the primary seal, the gas evacuation flowpath being separate from the first flowpath and being inserted so that the one or more vents are positioned in the patient's airway between the primary seal and the secondary seal for collecting a gas flow that leaks past the primary seal; collecting a gas that has leaked past the primary seal and into the patient's throat or mouth; and removing the collected gas from the patient using a vacuum system.

44. The method of claim 43, wherein the intubation device is an endotracheal tube.

45. The method of claim 43, wherein the intubation device is a laryngeal mask airway.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present teachings and together with the description, serve to explain the principles of the present teachings.

[0047] FIG. 1 is a perspective view of a cuffed patient airway tube fitted with a foam evacuation plug inserted into a patient's throat, according to an embodiment of the present disclosure.

[0048] FIG. 2 is an exploded view showing a patient airway tube with a cuff that is commonly used in operating rooms today; and a gas evacuation plug configured to attach to the airway tube, with a vacuum tube affixed thereto, according to an embodiment of the present disclosure.

[0049] FIG. 3 is a schematic view depicting one potential circuit layout of the device of FIG. 1, in conjunction with oxygen sensors and a gas monitoring device for use in an operating room environment, according to an embodiment of the present disclosure.

[0050] FIG. 4 illustrates a multi-lumen device, according to an embodiment of the present disclosure.

[0051] FIG. 5 is a perspective view of a separate tube that can be placed in a patient's airway in addition to and/or adjacent to an intubation device for providing surgical gas to a patient, such as an endotracheal tube, a laryngeal mask airway tube, or a nasal device, according to an embodiment of the present disclosure.

[0052] FIGS. 6 and 7 illustrate Guedel airways that can be employed as a gas evacuation device, according to an embodiment of the present disclosure.

[0053] FIG. 8 is a diagram of a standard Guedel Airway.

[0054] FIG. 9 illustrates a nasal trumpet device configured to collect gas from a patient, according to an embodiment of the present disclosure.

[0055] It should be noted that some details of the figure have been simplified and are drawn to facilitate understanding of the embodiments rather than to maintain strict structural accuracy, detail, and scale.

DESCRIPTION OF THE EMBODIMENTS

[0056] Reference will now be made in detail to embodiments of the present teachings, examples of which are illustrated in the accompanying drawings. In the drawings, like reference numerals have been used throughout to designate identical elements. In the following description, reference is made to the accompanying drawing that forms a part thereof, and in which is shown by way of illustration a specific exemplary embodiment in which the present teachings may be practiced. The following description is, therefore, merely exemplary.

[0057] An embodiment of the present disclosure is directed to a system for safely capturing surgical gases that have leaked past a seal that is engineered into a patient airway tube, such as an endotracheal tube, laryngeal airway mask, nasal trumpet or nasal tube, or other similar device; and to remove these gases from the patient without allowing them to disperse into the operating room. Oxygen/gas removal can significantly lower the risk for surgical fire and patient burns (e.g., burns in the lungs, airway/mouth, face, neck or shoulders). As an example, the seal can be formed using an inflated cuff, as is well known in the art.

[0058] In addition, the system can optionally include the ability to measure the amount of gas leakage that is occurring in real time and to show the operating room staff the current status of the tube seal at any given time. For example, the oxygen that is evacuated by the device may be monitored. Because the concentration ratio of oxygen to anesthetic gases in the leaking surgical gas is a known parameter, the system can use the monitored oxygen to calculate the total amount of leaking surgical gases and thereby provide feedback to the anesthesiologist about the relative volume of any leaks. In a similar manner, the exhaled anesthetic gas concentrations could also be measured to provide an indication of the magnitude of gas leakage while the patient is under anesthesia. One of ordinary skill in the art would readily be able to determine the magnitude of gas leakage given the exhaled anesthetic gas concentrations. Based on this data, the appropriate protocols to prioritize the patient's and the operating room staff's safety can be determined.

[0059] FIG. 1 illustrates a vented sleeve 100, according to an embodiment of the present disclosure. Sleeve 100 is configured to slip over an existing intubation device 102, which can be an endotracheal tube or laryngeal airway mask. Sleeve 100 fits above a seal 104 of the existing device in the patient's throat or mouth. One or more vents 106 are configured so that when a slight vacuum is applied to the operator end of the sleeve, evacuation of leaking surgical gas from the patient's throat or mouth through the attached conduit 108 results. FIG. 2 provides an exploded view showing patient airway tube 102 with a cuff, or seal 104, which is commonly used in operating rooms today. A sleeve 100 is shown configured to attach to the patient airway tube. A vacuum tube 108 is affixed thereto, according to an embodiment of the present disclosure.

[0060] In an embodiment, the sleeve 100 can comprise an expandable plug 110. Expandable plug 110 can comprise any suitable material. In one embodiment, the material is foam, such as an open cell foam, which is capable of expanding to fill the patient's mouth cavity to provide a secondary seal. Alternatively, plug 110 can comprise any other suitable material that can provide the desired secondary seal. In an embodiment, a flow path for evacuating the surgical gases can extend through the plug 110. Conduit 108 can attach to and/or extend through plug 110 as part of the flowpath. Conduit 108 can comprise any suitable material and can be, for example, vacuum tubing.

[0061] FIG. 3 illustrates a system 120 for monitoring gases in an operating room environment, according to an embodiment of the present disclosure. The system 120 comprises a patient airway tube 102 having a seal 104. A sleeve 100 is attached to tube 102. In an embodiment, the tube 102 and sleeve 100 can be those described above in connection with FIGS. 1 and 2.

[0062] One or more sensors 122 are fluidly connected to the sleeve 100. The one or more sensors are capable of real time, continuous monitoring of a gas that is drawn from a patient using the sleeve 100. In an embodiment, the gas being sensed can be chosen from oxygen gas, CO.sub.2 or anesthesia. Gas sensors 122 can also be used to determine pH of the gas evacuated from the patient.

[0063] The sensed gas levels coming from the patient can be compared to, for example, ambient levels of gases, such as CO.sub.2 or oxygen, in the operating room. For example, sensors 122 can be kept in a container that is separate from the ambient operating room atmosphere. Gas that is drawn from the patient can be compared to the ambient levels of oxygen in the operating room. If sensors 122 indicate higher oxygen concentrations in the gas drawn from the patient relative to the ambient levels, this would be indicative to the operator that a leak of surgical gases is occurring. Alternatively, in an embodiment employing a sensor that measures anesthetic gases directly, the sensor can provide a direct indication of any gas leakage without the need for comparison with ambient oxygen levels.

[0064] A gas monitoring device 124 can be in communication with the one or more sensors 122. Gas monitoring device 124 can include a component chosen from, for example, a data logger, alarm system or monitoring screen.

[0065] A vacuum pressure valve 126 is employed to provide a steady and suitably low level of vacuum pressure to the gas evacuation plug while it is placed inside the patient's throat or oral cavity. Vacuum pressure valve 126 can be connected to the operating rooms vacuum evacuation facility at, for example, point A.

[0066] As discussed above, the ability to provide a slight vacuum sufficient to evacuate a leaking surgical gas above a primary seal can allow the system to flow the leaking gas past an oxygen sensor, such as, for example, a sensor that is placed along the evacuation line itself. Because surgical gases comprise at least some oxygen, the system can be used to determine when the surgical gases are being leaked from the patient. For example, by measuring the concentration of oxygen in the gas and correlating it to the level of oxygen that is being used for that patient, the operator can monitor the relative amount of gas that is leaking from the patient at any given time. In an embodiment, this data can be provided to the operator in the form of a screen charting the trend line of the oxygen concentration of the gas that is being evacuated relative to the oxygen concentration in the operating room itself. In a similar manner, monitoring the concentrations of leaked anesthetic gases can also be used to determine the magnitude of the gas leak.

[0067] Charting this trend line can aid in several different aspects of the operating room's case management. Large volumes of enriched oxygen leaking into the operating room can be hazardous with regard to creating a fire hazard or an environment where flash fires can occur. This is both dangerous for patients and for operating room personnel. Being informed of leaking oxygen can serve to allow the anesthesiologist to limit the amount of gas escaping into the operating room and/or to take steps to prevent the buildup of such gases to dangerous levels.

[0068] As part of this process, the identification of a leak around the cuff of an endotracheal tube or other such device allows the operator to slightly increase the pressure on the inflatable cuff such that the minimum amount of inflation can be used to create an effective seal. This is an improvement over current practice, in that too much cuff inflation can cause harm to the patient's vocal cords and airway tissue, and discomfort to the patient. By determining the amount of pressure that can be employed to maintain an effective seal, an operator using this system would be able to accurately and continuously monitor the amount of pressure that is being used to inflate the cuff to insure the minimal level of patient discomfort or harm.

[0069] The system can also include the ability to notify the operating room personnel about anesthesia gas leakage by detecting the presence of increased concentration of CO.sub.2 from the gas that leaks. Ambient levels of CO.sub.2 gas are approximately 0.03% while CO.sub.2 in exhaled breath is approximately 4%. Due to the higher relative concentration of CO.sub.2 in exhaled breath, monitoring of the CO.sub.2 gas concentration in the evacuated gas stream coming from the patient can inform the anesthesiologist if exhaled breath is leaking from around the seal on the patient airway tube. The monitoring of CO.sub.2 can indicate a leak even when enriched oxygen is not being used during the surgery.

[0070] In addition to monitoring gas concentrations, the devices of the present disclosure can optionally include the ability to measure the pH level and/or to determine if acid is refluxing from the stomach into the airway region. The pH level or change thereof can be used to warn the surgical team of potential danger to the patient's airway. Sensing the pH can be performed in any desired manner. In an embodiment, gases collected from the patient can be analyzed to determine pH or changes in pH, which may be used to indicate reflux in the patient's airway. Devices for sensing pH levels of a gas flow are well known in the art. In another embodiment, the devices of the present disclosure can include a small probe (not shown) that sits near the airway. Any suitable pH probe can be employed. Suitable pH probes are well known and one of ordinary skill would readily be able to employ such probes, such as by positioning a pH probe on any of the airway devices of the present disclosure. If fluid comprising acidic contents from the patient's stomach comes into the region near the airway, the probe can identify a drop in pH. Regardless of the technique used to detect pH, the change in pH can be communicated to the operating team to make them aware of a potentially dangerous environment for the patient's airway. If these conditions are identified, an anesthesiologist can act appropriately, such as by removing the potentially harmful fluid from near the airway and/or by modifying the anesthesia technique appropriately to protect the patient.

[0071] FIG. 4 illustrates an intubation device comprising a fully integrated flowpath for evacuating leaking gases, according to an embodiment of the present disclosure. For example, the intubation device can be in the form of an endotracheal tube comprising a multi-lumen conduit. As illustrated in FIG. 4, an endotracheal tube can include a large lumen 140 that serves to deliver anesthetic gases into and out of the lungs of the patients, while one or more smaller lumens 142 are dedicated to providing vacuum pressure to evacuate any gasses that have leaked above the tube seal 104. Vents 144 provide fluid communication between the patient's airway above the seal 104 and the small lumen 142, thereby allowing leaking gas to flow into the small lumen 142 and out of the patient. Vacuum pressure can be provided by any suitable means, such as through conduit 108 attached to a port 146 in the multi-lumen conduit. The multi-lumen conduit can be made of any suitable material, such as, for example, PVC. The smaller lumen 142 can be in the form of a concentric annulus or any other suitable conduit configuration.

[0072] In an alternative embodiment, it may be possible to evacuate leaking gases without a secondary seal device. For example, in the embodiment of FIG. 4, sleeve 100 may be eliminated. Leaking gases can be collected by simply providing a sufficient vacuum through the one or more vents 144.

[0073] FIG. 5 illustrates a tubular device 150 that can be placed either through the patient's mouth or nares separately or together with an existing device 102 for providing surgical gases to a patient, according to an embodiment of the present disclosure. The tubular device 150 can include a cap or spacer positioned at or near the end of a tube. For example, the end of the tube can be fitted with a foam evacuation plug 152. The foam plug 152 can reduce the likelihood of developing an area of higher pressure suction that might damage the mucosal tissue. The tubular device can be placed in the patient's airway in addition to and/or adjacent to, for example, an endotracheal tube, a laryngeal mask airway tube, or a nasal airway tube.

[0074] The tubular device 150 allows for evacuating and/or monitoring surgical gases, such as oxygen and anesthetic gases that have leaked past a seal on an endotracheal tube, laryngeal mask airway tube, nasal device or other device for delivering oxygen and other gases to patients. A means can be employed for applying a vacuum to the tubular device 150 such that any oxygen or accompanying anesthetic gases that leak from around the seal are drawn from the patient and evacuated from the operating room, similarly as described for sleeve 100 and the system of FIG. 3. In an embodiment, tubular device 150 can replace sleeve 100 in the system of FIG. 3.

[0075] FIGS. 6 and 7 illustrate a Guedel airway design that can be used to evacuate or scavenge gas as it is leaking from a patient's throat. Geudel airways are generally well known in the art. A conventional Geudel airway is shown in FIG. 8. However, the Guedel airway 200, as shown in FIGS. 6 and 7, has been modified so that it can functionally replace the device of FIG. 1 in the system of FIG. 3. In an embodiment, the Guedel airway designs do not include a sleeve 100.

[0076] Guedel airway 200 includes vents 202 in the airway. Vents 202 are configured to allow gas in the patient's throat to move into the modified Guedel airway. Employing a plurality of vents 202 can provide redundant access to the airway from the patient's throat area in order to decrease the likelihood that tissue can be sucked up against a single vent opening when suction is applied to the airway and thereby clog the airway. If only a single opening 204 exists (as in the conventional airway of FIG. 8) the opening 204 can potentially be suctioned up against soft tissue in a patient's throat area and become occluded.

[0077] A flange 206 is positioned at an end of the Geudel airway. Flange 206 can be designed with notches 208 that can accommodate an endotracheal tube or LMA on either side of the Geudel airway. This can allow Geudel airway 200 to more easily sit directly adjacent to an endotracheal tube or LMA tube when the Geudel airway end opposite flange 206 is inserted into a patient's mouth and throat during surgery. The purpose of Geudel airway 200 is to remove gas that has leaked from, for example, an endotracheal tube or LMA seal that is also positioned in a patient's throat. The Geudel airway 200 can be attached to any suitable vacuum source to provide the desired suction. FIG. 7 illustrates an example of an adapter 210, which fits onto the Guedel airway and allows a user to easily attach an operating room vacuum source to the airway using a standard suction tube, such as conduit 108 in FIG. 1. For example, the adapter end 212 can be designed to be inserted into hole 204 at the flanged end of the Guedel airway to form an air-tight seal. Adaptor end 214 can be attached to the vacuum source. As oxygen and/or anesthetic are administered to the patient through the endotracheal tube or LMA, the vacuum source can suction any leaking gases through the vents 202 and hole 204 and into the Geudel airway 200. In an embodiment, the Guedel airway 200 can be used in place of the vented sleeve 100 in the system of FIG. 1.

[0078] Other embodiments may exist that serve to provide this same functionality and these same concepts may be applied to other devices that are used to assist patients in need of breathing assistance, such as nasal trumpets. For example, FIG. 9 illustrates a nasal trumpet 250 comprising holes 204, 214 for the main air flow, as well as vents 202, similar to the Geudel airway design, according to an embodiment of the present disclosure. If desired, the vents 202 can be placed in multiple positions along the nasal trumpet to increase the amount of captured gases from the patient and/or to reduce the chance of air flow blockage through the device. An adapter, such as adapter 210 of FIG. 7, can be used to provide a connection between the hole 204 of nasal trumpet 250 and the vacuum source. In an embodiment, the nasal trumpet 250 can be used in place of or in addition to the vented sleeve 100 in the system of FIG. 1. The nasal trumpet 250 is placed through the patient's nares, in addition to, or instead of using the traditional mouth area for access. If desired, a pH detection system as desired herein above can be used in combination with any of the airway devices of the present disclosure, including the nasal trumpet 250, Guedel airway 200, sleeve 100, nasal tube 150 or endotracheal tube devices of FIG. 1 or 4.

[0079] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all sub-ranges subsumed therein.

[0080] While the present teachings have been illustrated with respect to one or more implementations, alterations and/or modifications can be made to the illustrated examples without departing from the spirit and scope of the appended claims. In addition, while a particular feature of the present teachings may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular function. Furthermore, to the extent that the terms including, includes, having, has, with, or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term comprising. Further, in the discussion and claims herein, the term about indicates that the value listed may be somewhat altered, as long as the alteration does not result in nonconformance of the process or structure to the illustrated embodiment. Finally, exemplary indicates the description is used as an example, rather than implying that it is an ideal.

[0081] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompasses by the following claims.