Patent Application
20210322279
The present invention relates to improving respiratory monitory procedures and placement of orogastric/nasogastric or feeding tubes, and more broadly to a buteric acid detection based method and an apparatus for aspiration detection in respiratory assist device patients and for intubation verification of endotracheal tubes or other airway devices (e.g. laryngeal mask airways) and placement verification of orogastric or nasogastric tubes.
Respiratory Devices
Aspiration is generally defined as the entry of foreign material into the lungs. This can be due to inhalation of food or liquids during swallowing or due to regurgitation of stomach contents. Aspiration is schematically shown in Prior Art
Patient aspiration can lead to a number of patient complications including aspiration pneumonia and aspiration pneumonitis.
Studies have put incidence rates of aspiration pneumonia at around 5 to 15% of Community Acquired Pneumonia. See, for reference, Dibardina D M, Wunderrink R G (February 2015) “Aspiration Pneumonia: A Review of Modern Trends.” Journal of Critical Care. 30 (1): 40-48; See also Marik P E. “Aspiration pneumonitis and aspiration pneumonia” N Engl J Med 2001; 344:665-71. The rate of aspirational pneumonia can be as high as 20% in nursing home acquired pneumonia, see for reference Oh E, Weintraub N, Dhanani S. “Can we prevent aspiration pneumonia in the nursing home?” J Am Med Dir Assoc 2005; 6 (3 Suppl):S76-80, and Fein A M, “Pneumonia in the elderly. Special diagnostic and therapeutic considerations” Med Clin North Am 1994, 78:1015-33.
Additionally, it has been estimated that aspiration pneumonia occurs in 1 in every 2-3000 patients undergoing surgery, and this rate can be 3× higher in patients undergoing thoracic surgery. It occurs frequently in patients admitted with drug overdose and exhibits higher mortality rates. See Lanspa M, Peyrani P, Wiemkwn T, Wilson E, Ramirez J, Dean N (2015), “Characteristics associated with clinician diagnosis of aspiration pneumonia; a descriptive study of afflicted patients and their outcomes”. J Hosp Med. 10 (2): 90-6. It is the most common cause of death in patients suffering from dysphagia due to neurologic disorders, see van der Maarel-Wierink C D, Vanobbergen J N, Bronkhorst E M, Schols J M, de Baat C. “Meta-analysis of dysphagia and aspiration pneumonia in frail elders” J Dent Res 2011; 90:1398-404.
As alluded to above, aspiration is more common or becomes more likely with a number of conditions. For example, aspiration is more likely in the following conditions, including: difficulty swallowing (certain neurological conditions, stroke, etc.); vomiting, GERD, Placement and use of an NG tube, alcoholism, impaired consciousness, impaired cognition, seizures, use of a ventilator. See also a recent, at the time of this filing, paper by IlyaKagan, Moran Hellerman-ltzhaki, Ido Neuman, Yehuda D. Glass, Pierre Singer titled “Reflux events detected by multichannel bioimpedance smart feeding tube during high flow nasal cannula oxygen therapy and enteral feeding: First case report” Journal of Critical Care Volume 60, December 2020, Pages 226-229.
A separate complication of aspiration is aspiration pneumonitis, wherein the inhaled substances during aspiration are directly toxic to the lungs, causing chemical pneumonitis, also called Mendelson syndrome. Gastric acid, with a low pH (1.5-3.0), can cause corrosive damage to the lungs. Pneumonitis can resolve within a few days, or progress to Acute Respiratory Distress Syndrome (ARDS). There can also be a superimposed (aka secondary) bacterial infection in the tissue damaged by chemical pneumonitis. Aspiration pneumonitis is distinctly different from aspiration pneumonia. Aspiration pneumonitis (Mendelson's syndrome) is a chemical injury caused by the inhalation of sterile gastric contents, whereas aspiration pneumonia is an infectious process caused by the inhalation of oropharyngeal secretions that are colonized by pathogenic bacteria. Aspiration pneumonia presents with many of the same symptoms and signs as pneumonitis, but takes longer to develop. Fever caused by aspiration pneumonia is generally of a higher grade than in pneumonitis.
The applicant has been developing tools to minimize aspiration that can lead to the above complications. The applicant has developed a method of aspiration detection in respiratory assist device patients comprising the steps of: coupling an HCL sensor to one of a respiratory assist device of a patient; detecting the presence of HCL particles indicative of aspiration of the patient via a processer coupled to the HCL sensor; and displaying results for aspiration of the patient on the audio visual display. This earlier HCL sensor platform did have proposed applications in a variety of respiratory assist devices including in the nasal cannula and masks of ventilation systems and also in CPAP devices, Bipap devices and endotracheal tubes. The present invention represents continuation of this work, and can be considered an Butyric acid detection based platform in this same family.
An endotracheal tube is a specific type of tracheal tube that is nearly always inserted through the mouth (orotracheal) or nose (nasotracheal), and is a catheter that is inserted into the trachea for the primary purpose of establishing and maintaining a patent airway and to ensure the adequate exchange of oxygen and carbon dioxide. Tracheal intubation, usually simply referred to as intubaton, is the placement of a flexible catheter, e.g. plastic tube, into the trachea (windpipe) to maintain an open airway (or sometimes to serve as a conduit through which to administer certain drugs). It is frequently performed in critically injured, ill, or anesthetized patients to facilitate ventilation of the lungs, including mechanical ventilation, and to prevent the possibility of asphyxiation or airway obstruction.
Endotracheal tubes used for intubation can often be inserted incorrectly, particularly in traumatic scenarios. See Katz, S H; Falk, J L (2001). “Misplaced endotracheal tubes by paramedics in an urban emergency medical services system” (PDF). Ann Emerg Med. 37 (1): 32-7. See also Jones, J H; Murphy, M P; Dickson, R L; Somerville G G; Brizendine, E J (2004) “Emergency Physician Verified Out-of-Hospital Intubation: Miss Rates by Paramedics” Academic Emergency Medicine, 11(6): 707-9. In the prehospital setting, the incidence of unrecognized esophageal intubation has been reported to be as high as 1.8-2.0%, see Shea S R, MacDonald J R, Gruzinski G: “Prehospital endotracheal tube airway or esophageal gastric tube airway: A critical comparison” Ann Emerg Med 1985; 14:102-112.
There is a significant need for validation of proper endotracheal intubation. The position of the American College of Emergency Physicians, revised in 2016, states that confirmation of proper endotracheal tube placement should be completed in all patients at the time of initial intubation both in the hospital and out-of-hospital settings. Physical examination methods such as auscultation of chest and epigastrium, visualization of thoracic movement, and fogging in the tube are deemed not sufficiently reliable to confirm endotracheal tube placement. Similarly, pulse oximetry and chest radiography are not reliable as sole techniques to determine endotracheal tube location.
During intubation, direct visualization of the endotracheal tube passing through the vocal cords into the trachea, especially with the use of a video-laryngoscope, has been deemed to constitute firm evidence of correct tube placement, but additional techniques should be used as objective findings to confirm proper endotracheal tube position. The use of an end-tidal carbon dioxide detector (i.e., continuous waveform capnography, colorimetric and non-waveform capnography) has been proposed to evaluate and confirm endotracheal tube position in patients who have adequate tissue perfusion. However existing esophageal detector devices are deemed not as reliable as the various forms of capnography for the verification of endotracheal tube placement. Further, for patients in cardiac arrest and for those with markedly decreased perfusion, both continuous and non-waveform capnography may be less accurate. In these situations, if capnography is inconclusive, other methods of confirmation are desirable.
Ultrasound imaging may be used to reliably confirm endotracheal tube placement. However, this must be performed by someone who is experienced in this technique, and is not a practical real time solution in most applications. For background see Birmingham P K, Cheney F W, Ward R J: Esophageal intubation: A review of detection techniques. Anesth Analg 1986; 65:886-91; and Standards for Basic Anesthetic Monitoring, American Society of Anesthesiologists (last amended October 23), Directory of Members, 1996; 1998:438-9
There remains a need for a simple effective, efficient method and an apparatus for aspiration detection in respiratory assist device patients and for intubation verification of endotracheal tubes and other airway devices which can yield a reduction of morbidity and mortality of patients.
Gastric Tube
A conventional gastric tube 100 in a patient 10 is shown in
It has been estimated that around 1.2 million nasogastric tubes are inserted every year in the US. Similarly it has been estimated that 10 million nasogastric tubes are used yearly in Europe, with UK alone contributing to 1 million of those numbers. Some studies have suggested studies expect a 6.4% growth in usage by 2024. Other studies have noted that 24% of hospitalized pediatric patients in the US required temporary use of a NG/OG tube 100.
Currently, placement of gastric tubes 100 is accomplished, for a nasogastric tube 100 implementation, by using the nostril with the largest opening to insert the nasogastric tube 100 down the back of the nostril to the nasopharynx. The medical professional will generally ask the patient 10 to swallow once the tube 100 enters the nasopharynx. If the patient 10 is not able to mimic the swallowing action, the caregiver will often ask the patient 10 to sip water. For oro-gastric tubes 100 the technique is similar although placement starts in the oral cavity.
Complications that result from improper OG/NG tube 100 placement including pneumothorax, pulmonary hemorrhage, pleural effusion, empyema, trauma injuries, abscess formation, nose bleeds, asphyxia, secondary infections, pneumonitis, and development of tracheal-esophageal fistula. Other complications that can occur from improper tube 100 placement include tube migration, perforation of the tube 100, and the tube obstruction.
The ability to safely assess gastric tube 100 placement is a key skill that most medical professionals are required to learn. It is essential that the medical professional apply a systematic approach to such assessments as incorrect gastric tube 100 placement can result in life threatening complications. Historically, nurses or other qualified healthcare professionals can verify the placement of the OG/NG tube 100 by performing two of the following methods: asking the patient to hum or talk (wherein coughing or choking means the tube 100 is properly placed); use an irrigation syringe to aspire gastric contents; chest xray, lower the open end or proximal of the OG/NG tube 100 into a cup of water (bubbles indicate that the tube 100 is in place); or place a stethoscope over the patient's epigastrium while a 30 cc/m/bolus using an irrigation syringe (the air enters the stomach 14 when a whooshing sound is heard).
Methods that are most commonly used for confirming or verifying gastric tube 100 placement include: measuring the pH of aspirate using pH indicator strips or radiography (e.g. chest x-ray). Although other methods are discussed, currently these are the two modalities that are the most readily accepted. In the PH testing verification methodology, after a gastric tube 100 has been inserted, it is common practice to attempt to obtain an aspirate which then can have its pH checked. The idea is that gastric contents normally have a low pH (1.5-3.5) and therefore any aspirate that has a pH this low is likely to be located in the stomach 14 and unlikely to be located elsewhere (e.g. the respiratory tract). Aspiration and PH checking can therefore potentially be used as a method of confirming safe nasogastric placement without the additional need of chest X Ray if the pH is within a safe range (0-5.5). Local guidelines, however, can differ in terms of the acceptable pH range for confirming gastric tube 100 placement and some hospitals may require chest X-Rays for all patients 10, regardless of pH aspirate. Further hindering the PH testing method is that stomach pH can be altered by medications (e.g. proton pump inhibitors) and by the frequency of feeds.
There remains a need for an accurate, efficient and cost-effective method for proper placement confirmation or verification of gastric tubes 100.
One aspect of this invention is directed to A butyric acid detection based platform for verifying placement of a patient airway device or a gastric tube comprising at least one of i) a colorimetric based butyric acid detection platform, ii) a bioelectronic sensors based butyric acid detection platform using olfactory receptors, and iii) an IR based butyric acid detection platform, wherein each platform comprises a housing configured to be coupled to the patient airway device or a gastric tube whereby flow from the coupled patient airway device or a gastric tube can flow through an internal passage of the housing; and wherein each platform comprises sensors within the housing and configured to come into contact with the flow from the coupled patient airway device or a gastric tube, the sensors including at least one of a chemical sensor array including at least one of i) colorimetric based butyric acid sensor, ii) a bioelectronic butyric acid detection sensor using olfactory receptors, and iii) an IR based butyric acid sensor.
The term integrated within the meaning of the present invention defines that the system is found in a single unit, namely mounted within a single housing.
The term “multimodal” within the meaning of the specification referencing sensors indicates that the sensor, as a whole, is directed to measuring or detecting distinct parameters.
The phrase “multimodal colorimetric based” within the meaning of the specification references a plurality of distinct color changing based sensors, wherein the distinct sensors are directed to measuring or detecting distinct parameters.
One aspect of this invention is directed to an integrated multimodal colorimetric based aspiration detection system for a respiratory device including a housing configured to be coupled to the respiratory device whereby patient exhalation can flow through an internal passage of the housing; and colorimetric based sensors within the housing and configured to come into contact with the patient exhalation, where the colorimetric based sensors are visible from the exterior of the housing, and wherein the colorimetric sensors includes at least two of i) a CO2 sensor, ii) a sensor for a first gastric acid, iii) a sensor for a second gastric acid different from the first gastric acid, and iv) a PH sensor.
One aspect of this invention is directed to a colorimetric based aspiration detection system for a respiratory device comprising a housing configured to be coupled to the respiratory device whereby patient exhalation can flow through an internal passage of the housing, and at least one colorimetric based sensors within the housing and configured to come into contact with the patient exhalation, where each of the colorimetric based sensors are visible from the exterior of the housing, and wherein the colorimetric sensors includes at least a colorimetric sensor which senses butyric acid.
One aspect of the present invention provides a method of aspiration detection and intubation placement verification for an endotracheal tube comprising the steps of: Attempting to intubate the patient with an endotracheal tube; Providing an integrated multimodal colorimetric based aspiration detection and intubation placement verification system for an endotracheal tube having a housing and colorimetric based sensors within the housing, wherein the colorimetric sensors includes a CO2 sensor and at least one of i) a sensor for a first gastric acid, ii) a sensor for a second gastric acid different from the first gastric acid, and iii) a PH sensor; Coupling the housing to the endotracheal tube whereby patient exhalation can flow through an internal passage of the housing, wherein the colorimetric based sensors within the housing come into contact with the patient exhalation; and Visualizing the colorimetric based sensors from the exterior of the housing after they have come into contact with patient exhalation to detect aspiration and to verify intubation placement.
One aspect of the invention provides a method of aspiration detection and intubation placement verification for an endotracheal tube comprises: Attempting to intubate the patient with an endotracheal tube; Providing a multimodal aspiration detection and intubation placement verification system for an endotracheal tube having a housing and sensors within the housing, wherein the sensors include at least i) a sensor for a first gastric acid, and ii) a sensor for a second gastric acid different from the first gastric acid; Coupling the housing to the endotracheal tube whereby patient exhalation can flow through an internal passage of the housing, wherein the sensors within the housing come into contact with the patient exhalation; and Utilizing the sensor output for at least one of Detecting aspiration and to verification of intubation placement. The sensors include an electric chemical sensor array which can detect odor molecules at concentrations of less than 10 parts per billion in the gas phase.
One aspect of the invention provides an integrated multimodal aspiration detection system for a patient airway device comprising: A housing configured to be coupled to the endotracheal tube whereby patient exhalation can flow through an internal passage of the housing; sensors within the housing and configured to come into contact with the patient exhalation, the sensors including a chemical sensor array including at least one of i) a sensor for a first gastric acid, and ii) a sensor for a second gastric acid different from the first gastric acid.
One aspect of the invention provides an integrated multimodal bioelectronics based aspiration detection system for a respiratory device comprising: A housing configured to be coupled to the respiratory device whereby patient exhalation can flow through an internal passage of the housing; Bioelectric based sensors within the housing and configured to come into contact with the patient exhalation, where the bioelectric based sensors include includes an electric chemical sensor array with at least i) a sensor for a first gastric acid, and ii) a sensor for a second gastric acid different from the first gastric acid.
One aspect of the invention provides a method of gastric tube placement verification comprising the steps of: Inserting a gastric tube within the patient; Providing a colorimetric based gastric tube placement verification system for a patient gastric tube including i) a housing configured to be coupled to the gastric tube whereby stomach content aspirate can flow through an internal passage of the housing; and ii) at least one colorimetric based sensor within the housing and configured to come into contact with the patient stomach content aspirate, the least one colorimetric based sensor configures to detect a first gastric acid; Coupling the housing of the colorimetric based gastric tube placement verification system to a proximal end of the gastric tube; Aspirating stomach content of the patient whereby stomach aspirate can flow through an internal passage of the housing; and Visually inspecting at least one colorimetric based sensor within the housing for verification of proper gastric tube placement.
One aspect of the invention provides a colorimetric based gastric tube placement verification system for a patient gastric tube comprising: a housing configured to be coupled to the gastric whereby stomach content aspirate can flow through an internal passage of the housing; and at least one colorimetric based sensor within the housing and configured to come into contact with the patient stomach content aspirate, the least one colorimetric based sensor configures to detect a first gastric acid.
One aspect of the invention provides a colorimetric based gastric tube placement verification system for a patient gastric tube comprising: a housing configured to be coupled to the gastric whereby stomach content aspirate can flow through an internal passage of the housing; and a colorimetric sensor array comprising at least two colorimetric based sensors within the housing and configured to come into contact with the patient stomach content aspirate, including i) a sensor for a first gastric acid, and ii) a sensor for a second gastric acid different from the first gastric acid.
The features that characterize the present invention are pointed out with particularity in the claims which are part of this disclosure. These and other features of the invention, its operating advantages and the specific objects obtained by its use will be more fully understood from the following detailed description in connection with the attached figures.
One aspect of this invention is directed to an integrated butyric and HCL acid colorimetric based detection system or platform 200, 300, which would allow for a quick, effective and safe placement verification system for orogastric, nasogastric and feeding tubes collectively referenced as gastric tubes 100. The integrated butyric and HCL acid colorimetric based detection system or platform 200, 300 may also be implemented with respiratory assist devices such as an endotracheal tube or in the nasal cannula and masks of ventilation systems and also in CPAP devices and Bipap devices. Collectively the endotracheal tubes or the nasal cannula and masks of ventilation systems and also in CPAP devices and Bipap devices can be referenced collectively herein as patient airway device or respiratory tubes.
Each system 200 is used in a method of respiratory or gastric tube 100 placement verification comprising the steps of: Inserting a patient airway device or the gastric tube 100 within the patient 10 in a conventional fashion; Providing a colorimetric based respiratory or gastric tube placement verification system 200 for a patient respiratory or gastric tube 100 including i) a housing 210, 212 configured to be coupled to the patient airway device or the gastric tube 100 whereby the tube aspirate such as stomach 14 content aspirate can flow through an internal passage of the housing 210, 212; and ii) at least one colorimetric based sensor 218, 220, within the housing 210, 212, and configured to come into contact with the tube content aspirate, the least one colorimetric based sensor 218, 220 configures to detect HCL or Butyric Acid, respectively; Coupling the housing of the colorimetric based patient airway device or gastric tube placement verification system 200 to a proximal end of the patient airway device or gastric tube 100; Aspirating tube contents, such as stomach 14 content of the patient 10, whereby the tube aspirate can flow through an internal passage of the housing 210, 212; and Visually inspecting at least one colorimetric based sensor 218, 220 within the housing 210, 212 for verification of proper patient airway device or gastric tube 100 placement.
HCl, Hydrochloric acid or muriatic acid, is a primary acid found in the stomach and in stomach aspirate. Hydrochloric acid or muriatic acid is a colorless inorganic chemical system with the formula HCl. Hydrochloric acid has a distinctive pungent smell. It is classified as a strongly acidic acid and can attack the skin over a wide composition range, since hydrogen chloride completely disassociates in aqueous solution. Hydrochloric acid is the simplest chlorine-based acid system. It is the solution of hydrogen chloride and water in a variety of other chemical species including hydronium and chloride ions. It is a naturally occurring component of the gastric acid produced in the digestive system of most animal species, including humans.
Butyric acid, also known under the systematic name butanoic acid is a carboxylic acid with the structural formula CH3CH2CH2CO2H. Classified as a carboxylic acid, it is oily, colorless liquid that is soluble in water, ethanol, and ether. Isobutyric acid is an isomer. Butyric acid is a carboxylic acid found in rancid butter, parmesan cheese, and vomit, and has an unpleasant odor and acrid taste, with a sweetish aftertaste (similar to ether). Butyric acid is a fatty acid occurring in the form of esters in animal fats and plant oils.
As noted above,
The upper housing 210 includes sensor supports 216 in the form or slots receiving two colorimetric sensors 218 and 220 therein detecting HCL and Butyric Acid, respectively. In the embodiments of
For the purpose of the present invention the colorimetric sensors 218 and 220 will exhibit a color change generally in less than 2 seconds when exposed to the parameter of interest. For example, the colorimetric paper from Johnson Test paper forming the HCL sensor 218 changes color from blue to pink in the presence of HCl, with the sensitivity of the paper specified to be 0.5 ppm. The test or filter paper forming the Butyric Acid sensor 220 changes color in the presence of Butyric Acid, with the sensitivity of the paper specified to be 0.5 ppm. The sensor 220 should has a base color and a triggered color different from the sensor 218.
As noted above,
The upper housing includes sensor supports 216 which here are in the form of posts, again, receiving two colorimetric sensors 218 and 220 therein detecting HCL and Butyric Acid, respectively. The sensors 218 and 220 in
In summary, the system 200 of
Similarly, the system 200 of
The HCL sensor 218 and the butyric acid sensor 220 in the embodiments of
It is possible to add a third colorimetric sensor in the form of a PH colorimetric sensor which will effectively respond to the low PH of gastric acids. Adding a third sensor requires placement in a location that is visible through the housing 210 and 212. The normal pH range for stomach acid is between 1.5 and 3.5. The trigger point of the PH sensor may be selected within a range of intra-gastric PH ranges for humans. See pH dependence of acid secretion and gastrin release in normal and ulcer subjects. Walsh Richardson C T, Fordtran J S J Clin Invest. 1975 March; 55(3).462-8, One class of PH colorimetric sensor 20 is a graphene oxide based sensor that exhibits distinctive color response. See “Efficient Colorimetric pH Sensor Based on Responsive Polymer-Quantum Dot Integrated Graphene Oxide”, Kwanyeol Paek, Hyunseung Yang, Junhyuk Lee, Junwoo Park, and Bumjoon J. Kim ACS Nano 2014 8 (3), 2848-2856 DOI: 10.1021/nn406657b. As noted above the PH of the stomach 14 of the patient 10 can change such that the PH sensor should only supplement the remaining colorimetric sensor. Further the color of the PH sensor, if present, should differ from that of the sensors 218 ad 220.
The system 300 of
As noted above Butyric acid/HCl detection in system 200 or 300 can be achieved through direct contact of sensors 218, 220, 318, 320 with aspirate after connection to the proximal end of the OG/NG gastric tube 100. Attaching the detection device or system 200 or 300 to the proximal end of the OG/NG gastric tube 100 and then either attaching the opposite end to a suction device and/or a aspirating syringe, the aspirate will come in contact with the colorimetric paper sensor 218, 220, 318, 320 giving a positive color reaction when in the presence of butyric acid and or HCl.
The system 200 and 300 show several attachment sites for the colorimetric paper sensors 218, 220, 318, 320. The colorimetric paper sensors 218, 220, 318, 320 could be attached to the sides of the housing 210, 310 that will be exposed to the stomach aspirate as it is suctioned or drawn through the system 200 or 300. These housing could have colorimetric paper sensor receiving slots within the housing with perforations or small holes which allows for liquid contact with the colorimetric paper sensors. These access sites could have small access holes or vertical openings within the internal casing. Using the butyric acid/HCl colorimetric based detection system 200 or 300 for the confirmation of proper placement of gastric tubes 100, it allows for a far greater level of certainty rather than the current methods for detection of proper placement. The apparatus 200 or 300 can detect butyric acid and HCL in quantities of parts per millions with high specificity and selectivity. The apparatus 200 or 300 is configured to adapt to current orogastric/nasogastric and feeding tubes 100.
Presented herein are a few versions of butyric acid, HCl (and or pH) colorimetric sensor 218, 220, 318 and 320 designs and described operations. Note that the above descriptions are not exhaustive, and do not restrict the applicability of the approach presented here and are meant to serve as illustrations. Further embodiments of the apparatuses 200, 300 will become obvious after study of the apparatuses 200 and 300 presented herein by persons with experience in the art or area
Regarding specifically respiratory tubes, as discussed above, a critical step in the intubation of a patient is a determination that the breathing tube or intubation tube or endotracheal tube is placed in the trachea and not in the esophagus. The hydrochloric acid (HCL) sensor 218 is for measuring HCL concentrations of select samples of the patient exhalation. HCl is the primary acid found in the stomach. Assuming the endotracheal tube has been properly placed, the HCL sensor 218 activation (or trigger) is used for detecting aspiration of the patient. When the endotracheal tube is not properly placed the HCL sensor 20 will be triggered giving an active visual indication of improper placement. A key aspect of the present invention is the provision of a butyric acid sensor 220. Butyric acid is also known under the systematic name butanoic acid and is responsible for the stench of vomit. Thus, assuming the endotracheal tube has been properly placed, the butyric acid sensor 220 is also used for detecting aspiration of the patient. When the endotracheal tube is not properly placed the butyric acid sensor 220 will be triggered giving an active visual indication of improper placement. The HCL sensor 218 and the butyric acid sensor 220 operate on different parameters to achieve the same purpose.
Returning to the embodiment of
The integrated multi-modal colorimetric sensor platform 200 of the invention includes sensors 218 and 220 formed of colorimetric HCl paper and colorimetric butyric acid paper. The system 10 is to be attached to the bag-mask apparatus so that exhaled air comes in contact with it. After proper placement of the respiratory tube, should acidic vapors be present in exhaled air from regurgitation, the colorimetric HCl papers and the colorimetric butyric acid paper will change color, alerting the doctors and nurses to possible aspiration. This system pr platform 200 may be connected to the AMBU bag while ventilating patients and allows instant confirmation of correct placement of the endotracheal tube while also checking if aspiration has occurred by checking gaseous content of exhaled air. The system 200 is particularly useful in trauma patients.
The bioelectronic based sensors 420 in the housing shown in
The sensor 420 is multimodal for the system 400 of
The system 400 of
The integrated multimodal bioelectric based aspiration detection and placement verification system 400 of
Early detection and/or prevention of aspiration of emesis or other chemical/organic compounds via bioelectronic analysis of volatile organic compounds (VOCs) including butyric acid can decrease mortality and morbidity. Detecting exhaled or passively released VOCs (including butyric acid and/or other compounds readily found in emesis) facilitates timely early interventions, such as establishing airway protection (intubation), suctioning, pharmacological intervention (opiate and/or benzodiazepine reversal), elevating the head of the bed, and/or improving the level of consciousness, etc.
As shown in
The effective “bioelectronic nose” of the integrated multimodal bioelectric based aspiration detection and placement verification system 400 can detect odor molecules at extremely low concentrations of less than 10 parts per billion in the gas phase and less than 10 parts per million in liquid phase. The apparatus 400 is configured to discriminate the smells of emesis, preemptively avoiding aspiration or detecting aspiration earlier in the process. In short, binding the odorants of interest to the olfactory receptors of the bioelectronic nose electronic chemical array, the odorant products of emesis are timely recognized and an audiovisual alarm may be effectively and timely triggered.
Presented above are a few versions of the bioelectronic analyzer designs and described operations. Note that the preceding descriptions are not exhaustive, and do not restrict the applicability of the approach presented here and are meant to serve as illustrations. Further embodiments of the apparatuses will become obvious after study of the apparatuses presented here by persons with experience in the art or area.
This principle allows the creation of an IR based butyric acid detection platform 700 as generally shown in
The IR based butyric acid detection platform 700 includes a housing for the sensors 720 configured to be coupled to the gastric or endotracheal tube 100, face mask 600 and/or nasal cannula 500 whereby tubal contents such as patient exhalation can flow through an internal passage of the housing, and bioelectronic based sensors (combining to form the sensor 720) within the housing are configured to come in contact with the patient exhalation or other tubal contents.
The IR based butyric acid sensor 720 in the housing shown in
While the invention has been shown in several particular embodiments it should be clear that various modifications may be made to the present invention without departing from the spirit and scope thereof. The scope of the present invention is defined by the appended claims and equivalents thereto.
This application is a continuation in part of U.S. patent application Ser. No. 17/195,591 filed Mar. 8, 2021 titled “Integrated Multimodal Aspiration Detection and Intubation Placement Verification System and Method” which application is incorporated herein in its entirety. U.S. patent application Ser. No. 17/195,591 claims priority to U.S. Patent Application Ser. No. 62/986,630 filed Mar. 7, 2020 titled “Gas and Bioelectronic analysis/detection of compounds of emesis to facilitate early detection and/or prevention of aspiration and confirmation of correct placement of advanced airway equipment” which application is incorporated herein in its entirety. U.S. patent application Ser. No. 17/195,591 is a continuation in part of U.S. patent application Ser. No. 17/088,794 Filed Nov. 4, 2020 titled “Integrated Multimodal Colormetric Based Aspiration Detection and Intubation Placement Verification System and Method” which application is incorporated herein in its entirety. U.S. patent application Ser. No. 17/088,794 claims priority to U.S. Patent Application Ser. No. 62/930,096 filed Nov. 4, 2019 titled “Integrated Multimodal Colormetric Based Aspiration Detection and Intubation Placement Verification System and Method” which application is incorporated herein in its entirety. This application is a continuation in part of International Patent Application Serial Number PCT/US21/22438 filed Mar. 15, 2021 titled “Integrated Multimodal Aspiration Detection and Intubation Placement Verification System and Method” which application is incorporated herein in its entirety. International Patent Application Serial Number PCT/US21/22438 claims priority to U.S. Patent Application Ser. No. 62/988,925 filed Mar. 13, 2020 titled “COLORIMETRIC PAPER BASED CONFIRMANTION OF PROPER PLACEMENT OF OROGASTRIC/NASOGASTRIC AND FEEDING TUBES” which application is incorporated herein in its entirety. This application claims priority to U.S. Patent Application Ser. No. 63/041,998 filed Jun. 21, 2020 titled “BIOELECTRIC/OLFACTORY/DIGITAL OLFACTION CONFIRMATION OF PROPER PLACEMENT OF OROGASTRIC/NASOGASTRIC and FEEDING TUBES” which application is incorporated herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63041998 | Jun 2020 | US | |
| 62986630 | Mar 2020 | US | |
| 62930096 | Nov 2019 | US | |
| 62988925 | Mar 2020 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17195591 | Mar 2021 | US |
| Child | 17353187 | US | |
| Parent | 17088794 | Nov 2020 | US |
| Child | 17195591 | US | |
| Parent | PCT/US21/22438 | Mar 2021 | US |
| Child | 17088794 | US |
