Pulse oximeter device, method of self-calibration of a pulse oximeter device and non-transitory computer-readable storage medium

Abstract

The present invention refers to a pulse oximeter device (10, 20, 30, 40, 50), comprising: an external body (100); at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B); a photo emitter (300A); a photodetector (300B); wherein the photo emitter (300A) and the photodetector (300B) are positioned in the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) opposed to each other, and wherein the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) is configured to be inflated and deflated. The invention also refers to a method (1000) of self-calibration of a pulse oximeter device (10, 20, 30, 40, 50), comprising the following steps: i) emitting (1001) light by a photo emitter (300A) through at least one blood vessel of a user; ii) detecting (1002) by a photodetector (300B) wavelength-related data transmitted through or reflected by the at least one blood vessel; and iii.i) self-calibrating (1003) the pulse oximeter device (10, 20, 30, 40, 50) based on the wavelength-related data, in accordance with a self-calibration algorithm accounting for one or more among the differences of skin thickness, color variations, hemoglobin dissociation curve, motion of the user, and tissue perfusion.

Description

[0001] PULSE OXIMETER DEVICE, METHOD OF SELF-CALIBRATION OF A PULSE OXIMETER DEVICE AND NON-TRANSITORY COMPUTER-READABLE STORAGE MEDIUM FIELD OF THE INVENTION

[0002] The present invention relates generally to a devices and method used in the field of cardiovascular medicine for clinically assessing of a patient's health condition.

[0003] More specifically, the present invention relates to a pulse oximeter device for obtaining pulse rate and / or blood oxygen saturation data of a user, particularly but not restricted to children in emergency medical situations; a scenario in which quick and accurate diagnostics of pulse rate and / or blood oxygen saturation is paramount but may be hindered difficult or inaccurate in children with use of the prior art oximetry devices. In this regard, the pulse oximeter device comprises features that ease its fixation and adaptation to the child’s anatomy regardless of the child’s age or size, enhancing the accuracy of the vital readings.

[0004] The present invention also relates to a method of self-calibration of a pulse oximeter device based on wavelength-related data, in accordance with a selfcalibration algorithm considering the differences of skin thickness, color variations, hemoglobin dissociation curve and other anatomical and physiological factors.

[0005] BACKGROUND OF THE INVENTION

[0006] As is generally known, the circulatory system in human beings is responsible for transporting oxygen and other nutrients to the cells of the human body. The concentration of oxygen in hemoglobin molecules circulating through the body, as measured in the peripheral blood, is named “oxygen saturation”, and constitutes important information when determining the causes of several acute symptoms in the emergency setting, therefore allowing for proper treatment (Nitzan, M., Romem, A. K. Pulse oximetry: fundamentals and technology update. Med Devices Evid Res 2014:231-9); (Sheikh M, Ahmad H, Ibrahim R, Nisar I, Jehan F. Pulse oximetry: why oxygen saturation is still not a part of standard pediatric guidelines in low-and-middle income countries (LMICs). Pneumonia 2023;15(3):1-7. Doi: 10.1186 / s41479-023 00108-6).

[0007] One very simple and practical way of assessing blood oxygenation is the measuring of “pulse oximetry”, by using a portable, non-invasive, light emitting device that is able to determine hemoglobin concentrations in small blood vessels of the fingers using infrared beams (Ross PA, Newth CJL, Khemani RG. Accuracy of Pulse Oximetry in Children. Pediatrics 2014; 1(333):22-9. Doi: 10.1542 / peds.2013-1760).

[0008] The assessment of blood oxygen levels based on the spectral attributes of hemoglobin and oxyhemoglobin is a well-explored domain. Wood's innovation (U.S. patent number 2,706,927) introduced a method utilizing dual light wavelengths. Shaw's enhancement (U.S. patent number 3,638,640) expanded this approach by incorporating a broader range of light wavelengths. A significant practical breakthrough emerged when Aoyagi pioneered pulse-induced modulation in 1972. Further refinements were documented by Nielsen (U.S. patent number 4, 167,331 ) and Flower (U.S. patent number 4,863.265). These prior art inventions hinge on the quotient derived from the relative variable intensity of red light versus its infrared counterpart. This ratio unveils the absorbance ratio due to hemoglobin chromaticity, which correlates with oxygen bonding or saturation. Nonetheless, this technique is vulnerable to disturbances from motion effects and presents inherent inconsistencies across individual response patterns.

[0009] This drawback was resolved when self-calibrating devices were proposed which were able to provide a data-stream corresponding to the actual wavelength of light emitted, thereby allowing calibration of the sensor signal processing equipment and resulting in accurate measurements over a wider variation in emitter wavelength (Dietiker, U.S. patent number 7,124,048).

[0010] Recent technological advancements have led to significant reductions in the size and cost of pulse oximetry devices (Murthy RT, Sharadhi S, Varshini R, Rashmi S, Ambika \ / . A Review on Design and Development of loT Based Pulse Oximeter. J Res Proceedings 2021;1:1-10); (Floyd J, Wu L, Burgess DH, Izadnegahdar R, Mukanga D, Ghani AC. Evaluating the impact of pulse oximetry on resource-poor settings. Nature 2015; 3; 528 (7580): 53-9. Doi: 10.1038 / nature16043). Consequently, oximeter usage is now the standard of care in outpatient settings, emergency situations, and hospitalization, particularly in high-income countries.

[0011] These devices, nevertheless, are designed for a complying adult, and built in order to fit an adult's finger, as well as require a certain amount of time residing at adequate pressure in a resting finger in order to be able to properly acquire the oxygen readings (Pavone M, Verrillo E, Ullmann N, Caggiano S, Negro V, Cutrera R. Age and seasons influence on at-home pulse oximetry results in children evaluated for suspected obstructive sleep apnea. Italian Journal of Pediatrics 2017;1(43):1-7. Doi: 10. 1186 / sl 3052-017-0428-y.).

[0012] In this regard, respiratory diseases represent a significant global burden, contributing to both mortality and morbidity, with young people and babies being especially vulnerable. The spectrum of conditions ranges from immediate infections to chronic non-communicable diseases. The five most prevalent respiratory conditions are acute infections, chronic obstructive pulmonary disease (COPD), asthma, tuberculosis (TB), and lung cancer. Among these, pneumonia stands out as the primary cause of infant mortality, causing approximately 1.3 million avoidable deaths annually (ZarHJ, Ferkol TW. The global burden of respiratory disease-impact on child health. Pediatr Pulmonol 2014;49(5):430-4. Doi: 10.1002 / ppul.23030).

[0013] Infants and young children are particularly at risk of respiratory illnesses. While information from low and middle-income countries (LMICs) is limited, the available evidence suggests that over 90% of infant deaths related to respiratory issues occur within these geographical areas (United Nations Children’s Fund. Committing to Child Survival: A Promise Renewed Progress. www.apromiserenewed.or. 08 / 07 / 2023); (Nair H, Simd EAF, Rudan I, Gessner BD, Azziz-baumgartner E, Zhang JSF, et al. Global and regional burden of hospital admissions for severe acute lower respiratory infections in young children in 2010: a systematic analysis. Lancet 2013;381(9875):4-6. Doi: 10.1016 / S0140- 6736(12)61901-1).

[0014] Pulse oximetry plays a crucial role in evaluating respiratory issues in children. It is a non-invasive and reliable method for monitoring arterial blood oxygen saturation (SaC ), reflecting the adequacy of respiratory function (Nitzan, M., Romem, A. K. Pulse oximetry: fundamentals and technology update. Med Devices Evid Res 2014:231-9); (Gillor A, Schickendantz S, Heiner K MU. Noninvasive determination of oxygen saturation using pulse oximetry in pediatric cardiology. Monatsschr Kinderheilkd 1988;136:71-5).

[0015] By measuring photoplethysmographic pulses at two wavelengths, pulse oximeters can precisely determine SaO2 levels, enabling timely detection of hypoxia. This allows healthcare professionals to promptly intervene with appropriate treatment approaches such as supplemental oxygen, antibiotics, or early referral (Nitzan, M., Romem, A. K. Pulse oximetry: fundamentals and technology update. Med Devices Evid Res 2014:231-9). In developed nations, the widespread use of pulse oximetry for cardiorespiratory monitoring in children has yielded positive outcomes for severe respiratory illnesses (Sheikh M, Ahmad H, Ibrahim R, Nisarl, Jehan F. Pulse oximetry: why oxygen saturation is still not a part of standard pediatric guidelines in low-and- middle income countries (LMICs). Pneumonia 2023; 15(3): 1-7. Doi: 10.1186 / s41479- 023 00108-6).

[0016] Recognizing the substantial burden of hypoxemia in children with pneumonia and its potential impact on child survival, the World Health Organization (WHO) recommended the implementation of pulse oximetry in pediatric outpatient services, especially within the context of Integrated Management of Childhood Illness (IMCI) services, since 2014 (Rahman AE, Hossain AT, Nair H, Chisti MJ, Dockrell D, Arifeen S El, et al. Articles Prevalence of hypoxaemia in children with pneumonia in low-income and middle-income countries: a systematic review and meta-analysis. Lancet Glob Heal 2022;10(3):e348-59. Doi: 10.1016 / S2214-109X(21)00586-6); (World Health Organization. Pocket book of hospital care for children: guidelines for the management of common childhood illnesses: World Health Organization. 2013); (Integrated Management of Childhood Illness - World Health Organization. Chart Booklet. 2014).

[0017] However, several factors affect the accuracy of pulse oximetry, particularly in terms of obtaining successful readings and the time required for it (Enoch AJ, English M, Mcgivern G, Shepperd S. Variability in the use of pulse oximeters with children in Kenyan hospitals: A mixed-methods analysis. PLoS Med 2019;31(16):e1002987. Doi: 10.1371 / journal.pmed.1002987); (Trivedi NS, Ghouri AF, Shah NK, Lai E, Barker SJ. Effects of Motion, Ambient Light, and Hypoperfusion on Pulse Oximeter Function. J Clin Anesth 1997;9(3):179-83); (Yamaya Y, Bogaard HJ, Wagner PD, Niizeki K, Hopkins SR, Bogaard H J, et al. Validity of pulse oximetry during maximal exercise in normoxia, hypoxia, and hyperoxia. J Appt Physiol 2023,92(1): 162- 8); (Sola A, Rogido LCM. Oximetria de pulso en la asistencia neonatal en 2005. Revision de los conocimientos actuales. An Pediatric (Bare) 2015;62(3):266-81); (Boyd N, King C, Walker I A, Zadutsa B, Bernstein M, Ahmed S, et al. Usability Testing of a Reusable Pulse Oximeter Probe Developed for Health-Care Workers Caring for Children < 5 Years Old in Low-Resource Settings. Am J Trop Med Hyg 2018;99(4):1096-104. Doi: 10.4269 / ajtmh. 18-0016); (Baquero H, Alviz R, Castillo A, Neira F, Sola A. Avoiding hyperoxemia during neonatal resuscitation: time to response of different SpO2 monitors. Acta Pediatric 2011;100(4):515-8. Doi: 10.1111 / J.1651- 2227.2010.02097.x). These factors can be broadly categorized into three groups: device- related factors, patient-related factors, and factors influenced by healthcare professionals. Unfortunately, most existing evidence on this subject comes from resource-rich environments and high-income countries, predominantly in qualitative investigations (Ewer AK, Middleton LJ, Furmston AT, Bhoyar A, Daniels JP, Thangaratinam S, et al. Pulse oximetry screening for congenital heart defects in newborn infants (PulseOx): a test accuracy study. Lancet 2011 ;378(9793):785-94. Doi: 10.1016 / S0140-6736(11)60753-8); (Anderson CG, Benitz WE. Original Article Retinopathy of Prematurity and Pulse Oximetry: A National Survey of Recent Practices. J Peri natol 2004; 24(3): 164-8. Doi: 10.1038 / sj.jp.7211067); (Brouillette RT, Morielli A, Leimanis A, Waters KA, Ducharme PM, Brouillette RT, etal. Nocturnal pulse oximetry as an abbreviated testing modality for pediatric obstructive sleep apnea. Pediatrics 2000;105(2):405-12. Doi: 10.1542 / peds.105.2.405); (King C, Boyd N, Walker I, Zadutsa B, Baqui AH, Ahmed S, et al. Opportunities and barriers in pediatric pulse oximetry for pneumonia in low-resource clinical settings: a qualitative evaluation from Malawi and Bangladesh. BMJ Open 2018;8:e019177. Doi: 10.1136 / bmjopen- 2017-019177); (Mallory MD, Shay DK, Garrett J, Bordley WO, Objective A. Bronchiolitis Management Preferences and the Influence of Pulse Oximetry and Respiratory Rate on the Decision to Admit Pediatrics 2003; 111(1 ):e45-51).

[0018] Factors such as skin color and child age have shown high rates of reading variability and low sensitivity to hypoxic states (Ross PA, Newth CJL, Khemani RG. Accuracy of Pulse Oximetry in Children. Pediatrics 2014;1(333):22-9. Doi: 10.1542 / peds.2013-1760); (Pavone M, Verrillo E, Ullmann N, Caggiano S, Negro V, Cutrera R. Age and seasons influence on at-home pulse oximetry results in children evaluated for suspected obstructive sleep apnea. Italian Journal of Pediatrics 2017;1(43):1-7. Doi: 10.1186 / s13052-017-0428-y); (Gray KD, Subramaniam HL, Huang ES. Effects of Racial Bias in Pulse Oximetry on Children and How to Address Algorithmic Bias in Clinical Medicine. JAMA Pediatric 2023;177(5):459-60. Doi: 10.1002 / pds.2343).

[0019] In the study by Rahman et al., the time required for obtaining a suitable reading in hospitalized children ranged up to 50 seconds, depending on the underlying respiratory condition (Rahman AE, Hossain AT, Majid T, Azim AFM, Alam MS, Saberin A, et al. Success and time implications of SpO2 measurement through pulse oximetry among hospitalized children in rural Bangladesh: Variability by various device, provider and patient-related factors. J Glob Heal 2022; 23: 12:04036. Doi:

[0020] 10.7189 / jogh. 12.04036).

[0021] In pediatric emergency scenarios, rapid pulse oximetry assessments are crucial for promptly evaluating children's respiratory status and guiding immediate interventions (Ross PA, Newth CJL, Khemani RG. Accuracy of Pulse Oximetry in Children. Pediatrics 2014;1(333):22-9. Doi: 10.1542 / peds.2013-1760); (Duke T, Subhi R, Peel D, Frey B. Pulse oximetry: technology to reduce child mortality in developing countries. Ann Trop Paediatr. 2009;3(29):165-75. Doi: 10. 1179 / 027249309X12467994190011).

[0022] In the setting of a pediatric emergency room, in which the patient is not only far less compliant, but also much smaller, the prior art devices have proven less reliable, as well as less efficient in terms of time required for readings to be performed. This leads to incorrect assessments, with possible overuse of commodities such as supplementary oxygen, as well as delay in diagnosis and institution of treatment (Nitzan, M., Romem, A. K. Pulse oximetry: fundamentals and technology update. Med Devices Evid Res 2014:231-9); (Sheikh M, Ahmad H, Ibrahim R, Nisar I, Jehan F. Pulse oximetry: why oxygen saturation is still not a part of standard pediatric guidelines in low-and-middle income countries (LMICs). Pneumonia 2023;15(3):1-7. Doi: 10.1186 / S41479-023 00108-6); (Rahman AE, Hossain AT, Majid T, Azim AFM, Alam MS, Saberin A, et al. Success and time implications of SpO2 measurement through pulse oximetry among hospitalized children in rural Bangladesh: Variability by various device provider and patient-related factors. J Glob Heal 2022,23:12:04036. Doi: 10.7189 / jogh. 12.04036).

[0023] There are several patented wearable devices for monitoring of children’s health parameters, such as the one disclosed in Chinese patent number 204995455 II and in WO application number 2014035836 A1 having several counterpart applications in different countries. Nevertheless, these are designed for long-term monitoring and require proper adjustment and fitting.

[0024] In view of the above, it is clear that the prior art lacks technological innovations for a pulse oximeter device for obtaining pulse rate and / or blood oxygen saturation data of a user, particularly but not restricted to children in emergency medical situations, especially in which the pulse oximeter device comprises features that ease its fixation and adaptation to a child’s anatomy regardless of the child’s age or size, with proper pressure, enhancing the accuracy of the vital readings. It is also evident that the prior art lacks technological innovations for a method of self-calibration of a pulse oximeter device based on wavelength-related data, in accordance with a self-calibration algorithm considering the differences of skin thickness, color variations, hemoglobin dissociation curve and other anatomical and physiological factors.

[0025] PURPOSES AND DESCRIPTION OF THE INVENTION

[0026] Thus, a first general objective of the present invention is to provide a pulse oximeter device which is capable of eliminating or at least reducing the limitations of the currently known techniques.

[0027] A particular objective of the present invention is to provide the pulse oximeter device having pneumatic features that ease its fixation and adaptation to a child’s anatomy regardless of the child’s age or size, with proper pressure, enhancing the accuracy of the vital readings as current devices fail to adequately conform to children's anatomy and often lack suitable programming for their clinical range of oximetry.

[0028] A second general objective of the present invention is to provide a method of self-calibration of a pulse oximeter device which is capable of eliminating or at least reducing the limitations of the currently known techniques.

[0029] A particular objective of the present invention is to provide the method of self-calibration of a pulse oximeter device considering specific factors related to a child’s anatomy or physiology in order to reduce the rate of vitals reading variability and errors.

[0030] One or more purposes of the present invention, mentioned above, among others, is(are) reached by means of a pulse oximeter device, comprising, at least:

[0031] - an external body;

[0032] - at least one internal body;

[0033] - a photo emitter;

[0034] - a photodetector; wherein the photo emitter and the photodetector are positioned in the at least one internal body opposed to each other, and wherein the at least one internal body is configured to be inflated and deflated.

[0035] One or more purposes of the present invention, mentioned above, among others, is(are) reached by means of a method of self-calibration of a pulse oximeter device, comprising at least the following steps: i) emitting light by a photo emitter through at least one blood vessel of a user; ii) detecting by a photodetector wavelength-related data transmitted through or reflected by the at least one blood vessel; iii.i) self-calibrating the pulse oximeter device based on the wavelength- related data, in accordance with a self-calibration algorithm accounting for the differences of skin thickness, color variations, hemoglobin dissociation curve, motion of the user, and tissue perfusion.

[0036] One or more purposes of the present invention, mentioned above, among others, is(are) reached by means of a non-transitory computer-readable storage medium comprising a set of instructions stored therein that when executed by a computer processor, cause the processor to perform at least the step iii.i) of the method of self-calibration of a pulse oximeter device.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] To elucidate the means by which the aforementioned benefits and attributes of this invention may be acquired, a more detailed portrayal of the invention, as briefly outlined earlier, shall be described by referring to distinct embodiments thereof, as portrayed in the appended illustrations. It is imperative to emphasize that the illustrations are not proportionally rendered, and that components sharing akin structure or purpose are generally indicated by analogous reference numerals for the sake of elucidation throughout the illustrations.

[0039] All of the various embodiments, aspects and options disclosed herein may be combined in all variations, regardless of whether such features or elements are expressly combined in a specific embodiment description herein. This presently claimed invention is intended to be read holistically, so that any separable features or elements of the disclosed invention, in any of its various aspects and embodiments, are viewed as intended to be combinable, unless the context clearly dictates otherwise.

[0040] All method steps of the present invention described herein may be performed in any suitable order, unless otherwise indicated in this specification or otherwise clearly contradicted by the context.

[0041] Acknowledging that these depictions solely portray possible embodiments of the invention and are, hence, not to be construed as limiting of its scope, shape or features, the device and method are better detailed and elucidated with supplementary precision and thoroughness through the accompanying illustrations, as follows:

[0042] - Figure 1A illustrates a front view of the pulse oximeter device 10 in a resting condition, according to a first embodiment of the present invention;

[0043] - Figure 1 B illustrates a top perspective view of the pulse oximeter device 10 in the resting condition, according to the first embodiment of the present invention;

[0044] - Figure 1 C illustrates a hidden-line top perspective view of the pulse oximeter device 10 in the resting condition, according to the first embodiment of the present invention;

[0045] - Figure 2A illustrates a front view of the pulse oximeter device 10 in an active condition, according to the first embodiment of the present invention;

[0046] - Figure 2B illustrates a top perspective view of the pulse oximeter device 10 in the active condition, according to the first embodiment of the present invention;

[0047] - Figure 2C illustrates a hidden-line top perspective view of the pulse oximeter device 10 in the active condition, according to the first embodiment of the present invention;

[0048] - Figure 2D illustrates a front view of the pulse oximeter device 10 in the resting condition, depicting a distance D1 between a photo emitter 300A and a photoreceptor 300B according to the first embodiment of the present invention;

[0049] - Figure 2E illustrates a front view of the pulse oximeter device 10 in the active condition, depicting a distance D2 between the photo emitter 300A and the photoreceptor 300B according to the first embodiment of the present invention;

[0050] - Figure 3A illustrates a top perspective view of the pulse oximeter device 10 in the resting condition in a possible proposed functioning setting for the pulse oximeter device 10 as attached to a child's wrist 600;

[0051] - Figure 3B illustrates a top perspective view of the pulse oximeter device 10 in the resting condition in a possible proposed functioning setting for the pulse oximeter device 10 as attached to a child's ankle 700;

[0052] - Figure 4A illustrates a front view of the pulse oximeter device 20 in a resting condition, according to a second embodiment of the present invention;

[0053] - Figure 4B illustrates a top perspective view of the pulse oximeter device 20 in the resting condition, according to the second embodiment of the present invention;

[0054] - Figure 5A illustrates a front view of the pulse oximeter device 30 in a resting condition, according to a third embodiment of the present invention; - Figure 5B illustrates a top perspective view of the pulse oximeter device 30 in the resting condition, according to the third embodiment of the present invention;

[0055] - Figure 6A illustrates a front view of the pulse oximeter device 40 in an active condition, according to a fourth embodiment of the present invention;

[0056] - Figure 6B illustrates a top perspective view of the pulse oximeter device 40 in the active condition, according to the fourth embodiment of the present invention;

[0057] - Figure 7A illustrates a front view of the pulse oximeter device 50 in a resting condition, according to a fifth embodiment of the present invention;

[0058] - Figure 7B illustrates a top perspective view of the pulse oximeter device 50 in the resting condition, according to the fifth embodiment of the present invention;

[0059] - Figures 8A and 8B illustrate top perspective views of possible proposed presentations for the device 10, 20, 30, 40, 50 finishings;

[0060] - Figure 8C illustrates a possible proposed design for an external body 100 shape variation of the pulse oximeter device 10, 20, 30, 40, 50 for a children- friendly appearance, such as, but not limited to, a puffer-fish shape;

[0061] - Figure 8D illustrates a possible proposed design for surface patterns applied to an external body 100 of the pulse oximeter device 10, 20, 30, 40, 50 for a children-friendly appearance, such as, but not limited to, puffer-fish surface patterns;

[0062] - Figure 9 illustrates a manual pneumatic pump 800 to be attached to a pneumatic port 120A of the pulse oximeter device 10, 20, 30, 50, according to some embodiments of the present invention; and

[0063] - Figure 10 illustrates a flowchart comprising steps 1001 to 1006 of the method 1000 of self-calibration of a pulse oximeter device, according to an embodiment of the present invention.

[0064] DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

[0065] Initially, it must be highlighted that the device 10, 20, 30, 40, 50, and method 1000 of the present invention, namely, a pulse oximeter device 10, 20, 30, 40, 50, and a method 1000 of self-calibration of a pulse oximeter device will be described in accordance with particular, but non-limiting embodiments, since the embodiments thereof can be carried out in different manners and variations according to the desired application.

[0066] In all of the embodiments that will be disclosed herein, the present invention discloses a pulse oximeter device 10, 20, 30, 40, 50, comprising an external body 100 and at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B. The at least one internal body 110, 210, 310, 410A, 41 OB, 51 OA, 51 OB is configured to be pneumatically inflated (in an active condition) and deflated (in a resting condition), which is accomplished by the action of manual or electronic pneumatic pumps 800, 440 and pneumatic valves 820 or any other suitable mechanical or electronic means. For that purpose, the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B may be made of any suitable elastic material that allows for the pneumatic insufflation thereof, such as, but not limited to, rubber, latex and the like.

[0067] In all of the embodiments that will be disclosed herein, the external body 100 serves as the pulse oximeter device 10, 20, 30, 40, 50 support frame, limiting the expansion of the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B, and preventing external damage to the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B and its components. For those purposes, the inner face of the external body 100 is lined with the material of the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B, and the external body 100 may be made of a sturdy material, such as suitable polymers (such as illustrated in figure 8A), metals (such as illustrated in figure 8B) and the like.

[0068] Furthermore, In all of the embodiments that will be disclosed herein, a photo emitter 300A, particularly but not limited to an infrared and red light wavelength emitter, is affixed to one portion of the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B, be it the upper face, lower face, one of the lateral sides or diagonal sides. Likewise, a photoreceptor 300B is affixed to a portion of the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B be it the upper face, lower face, one of the lateral sides or diagonal sides, preferably, but not limited to, a portion that exactly opposes the portion to which the photo emitter 300A is affixed to.

[0069] When the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B is in the deflated resting condition, a distance D1 between the photo emitter 300A and the photodetector 300B is greater than a distance D2 between the photo emitter 300A and the photodetector 300B when the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B is in the inflated active condition, as illustrated in figures 1A and 2A.

[0070] In all of the embodiments that will be disclosed herein, the external body 100 and the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B form a closed-loop shape or a semi-closed loop shape that, when in the resting condition allows a user’s body part, preferably, but not limited to, a child’s hand, wrist 600, finger, foot, ankle 700, or toe to be confined by the shape, such as exemplified in figures 3A and 3B. It is important to note that the illustrated device is not up to scale and in case the body part is a finger, the pulse oximeter device 10, 20, 30, 40, 50 may be smaller for that purpose.

[0071] Once the child’s body part is confined by the closed-loop shape or a semiclosed loop shape, the at least one internal body 110, 210, 310, 410A, 410B, 510A, 510B is pneumatically inflated to the active condition, expanding around the child’s body part, thereby reducing the distance D1 to D2 and causing the photo emitter 300A and the photoreceptor 300B to come into a precise and tight contact with the child’s body part skin, allowing for a precise reading of the child’s pulse rate and blood oxygen saturation, regardless of the child’s age or size. The photo emitter 300A emits an infrared and a red light wavelength beam, both of which traverse the capillary vessels in the assessed body part. The O2-bound hemoglobin molecules in these vessels partially absorb the infrared beam. The red light beam functions as a stable light source, negating the need for preliminary device calibration. The photoreceptor 300B then receives both beams, accurately detecting blood volume and the amount of absorbed infrared light. Consequently, the device estimates blood oxygenation and / or pulse rate, enabling a swift diagnosis, timely intervention and personalized healthcare management.

[0072] In all of the embodiments that will be disclosed herein, the pulse oximeter device 10, 20, 30, 40, 50 is mainly designed for optimization of the fixation and adaptation to any child’s body part regardless of the child’s age or size. For this reason, the pulse oximeter device 10, 20, 30, 40, 50 also presents a solution for oximetry and / or pulse rate readings in any clinical setting such as, but not restricted to, quick screening readings as well as long-term monitoring of the blood oxygen saturation and / or pulse rate, in any clinical setting of a hospital or health institution. Settings for device application may include, although is not limited to: a) emergency pediatric care, b) pediatric clinical observation wings, c) long-term monitoring in in-hospital settings, d) long-term monitoring in intensive care settings, e) long-term monitoring in surgical care settings, f) fast diagnosis in a home setting and g) long-term monitoring in home care setting.

[0073] In all of the embodiments that will be disclosed herein, in order to make the pulse oximeter device 10, 20, 30, 40, 50 more child-friendly, which ultimately also helps in obtaining a precise reading of blood oxygen saturation and / or pulse rate as the child tends to be less energetic and more prone to being subjected to the device, the external body 100 may comprise one or more design variants 900, varying in shape and material, such as, but not limited to, animal shapes, toy shapes, and other amicable designs and configurations as exemplified in figure 8C, the external body 100 may also comprise ornamental pattens of animal, toys or the like, such as, but not limited to, a puffer fish as exemplified in figure 8D. The external body 100 may be removable and washable.

[0074] In all of the embodiments that will be disclosed herein, the pulse oximeter device 10, 20, 30, 40, 50 also comprises one or more processors, one or more power sources 440, analog or digital interface 420 and a data storage unit, such as a non- transitory computer-readable storage medium storing a self-calibration algorithm, and an electronic system for data processing and sharing which enables systems communication for the measurement data retrieving into personal devices such as, but not limited to, smartphones, portable computers and tables for remote follow up of the measurement data.

[0075] EMBODIMENTS OF THE DEVICE

[0076] According to a first preferred embodiment, as illustrated in figures 1A to 3B, the external body 100 of the pulse oximeter device 10 has a closed-loop shape, such as an oval shape. However, the pulse oximeter device 10 may be of any other closed-loop shape such as, but not limited to, round, square, trapezoid, elliptical or any other closed-loop polygonal shape. In this embodiment, the at least one internal body 110 has a continuous shape, following the entire inner face of the external body 100.

[0077] In this embodiment, as illustrated by figures 2D and 2E, due to its continuous shape, beyond reducing the distance D1 between the photo emitter 300A and the photoreceptor 300B, the at least one internal body 110 when inflated, reduces a distance between a geometric centerline C of the pulse oximeter device 10 and the internal body 110 in all directions from the centerline C, which ensures a tighter grip in the child’s body part, preventing reading errors in case the photo emitter 300A and the photoreceptor 300B loose contact with the skin of the child’s body part.

[0078] In this embodiment, as illustrated by figures 1 A to 3B, the pulse oximeter device 10 comprises a pneumatic port 120A pneumatically associated with at least one pneumatic line, as illustrated by figure 1 C the at least one internal body 110 and the manual pneumatic pump 800 as illustrated in figure 9.

[0079] In this embodiment, the pneumatic line is the interior of the at least one internal body 110, which receives air coming from the pneumatic hose 830 of the regular manual pneumatic pump 800, by pumping the insufflation bulb 810. In order to bring the at least one internal body 110 back to the resting condition, the pneumatic valve 820 must be opened.

[0080] According to a second embodiment, as illustrated in figures 4A and 4B, the external body 100 of the pulse oximeter device 20 has a semi-closed loop shape, such as a cuff shape with an open end 220 which allows a snap-fit to the child’s body part. In this embodiment, the at least one internal body 210 has a continuous shape, following the entire inner face of the external body 100.

[0081] In this embodiment, such as illustrated by figures 2D and 2E, due to its continuous shape, beyond reducing the distance D1 between the photo emitter 300A and the photoreceptor 300B, the at least one internal body 210 when inflated, reduces a distance between a geometric centerline C of the pulse oximeter device 20 and the internal body 210 in all directions from the centerline C, which ensures a tighter grip in the child’s body part, preventing reading errors in case the photo emitter 300A and the photoreceptor 300B loose contact with the skin of the child’s body part.

[0082] In this embodiment, as illustrated by figures 4A and 4B, the pulse oximeter device 20 comprises a pneumatic port 120A pneumatically associated with at least one pneumatic line, the at least one internal body 110 and the manual pneumatic pump 800 as illustrated in figure 9.

[0083] In this embodiment, the pneumatic line is the interior of the at least one internal body 210, which receives air coming from the pneumatic hose 830 of the regular manual pneumatic pump 800, by pumping the insufflation bulb 810. In order to bring the at least one internal body 210 back to the resting condition, the pneumatic valve 820 must be opened.

[0084] According to a third embodiment, as illustrated in figures 5A and 5B, the external body 100 of the pulse oximeter device 30 has a semi-closed loop shape, such as a cuff shape with a closable end which allows an adjustable fit to the child’s body part. The closable end is closable by a strap 320, which may comprise one of hook- and-loop fastener or magnetic fastener.

[0085] In this embodiment, the at least one internal body 310 has a continuous shape, following the entire inner face of the external body 100. Such as illustrated by figures 2D and 2E, due to its continuous shape, beyond reducing the distance D1 between the photo emitter 300A and the photoreceptor 300B, the at least one internal body 310 when inflated, reduces a distance between a geometric centerline C of the pulse oximeter device 30 and the internal body 310 in all directions from the centerline C, which ensures a tighter grip in the child’s body part, preventing reading errors in case the photo emitter 300A and the photoreceptor 300B loose contact with the skin of the child’s body part.

[0086] In this embodiment, as illustrated by figures 5A and 5B, the pulse oximeter device 30 comprises a pneumatic port 120A pneumatically associated with at least one pneumatic line, the at least one internal body 310 and the manual pneumatic pump 800 as illustrated in figure 9.

[0087] In this embodiment, the pneumatic line is the interior of the at least one internal body 310, which receives air coming from the pneumatic hose 830 of the regular manual pneumatic pump 800, by pumping the insufflation bulb 810. In order to bring the at least one internal body 310 back to the resting condition, the pneumatic valve 820 must be opened.

[0088] According to a fourth embodiment, as illustrated in figures 6A and 6B, the external body 100 of the pulse oximeter device 40 has a closed loop shape, such as an oval shape. However, the pulse oximeter device 40 may be of any other closed- loop shape such as, but not limited to, round, square, trapezoid, elliptical or any other closed-loop polygonal shape. In this embodiment, the at least one internal body 410A, 410B has a non-continuous shape, such as a first 410A and a second 410B dome.

[0089] In this embodiment, the pulse oximeter device 40 comprises a pneumatic port pneumatically associated with at least one pneumatic line, the at least one internal body 410A, 410B and at least one electronic pneumatic pump 440 as illustrated in figure 6A.

[0090] In this embodiment, the pneumatic line connects both first 410A and second 410B domes, which receives air coming insufflated by the at least one electronic pneumatic pump 440. In order to bring the first 410A and second 410B domes back to the resting condition, a pneumatic valve must be opened.

[0091] In this embodiment, the pulse oximeter device 40 has a built-in interface 420, such as a display for displaying the measured pulse rate and / or blood oxygen saturation. Both the at least one electronic pneumatic pump 440 and the built-in display 420 are powered by a battery 430.

[0092] According to a fifth embodiment, as illustrated in figures 7A and 7B, the external body 100 of the pulse oximeter device 50 has a closed loop shape, such as an oval shape. However, the pulse oximeter device 50 may be of any other closed- loop shape such as, but not limited to, round, square, trapezoid, elliptical or any other closed-loop polygonal shape. In this embodiment, the at least one internal body 510A, 51 OB has a non-continuous shape, such as a first 510A and a second 51 OB bellow.

[0093] In this embodiment, the pulse oximeter device 50 comprises a pneumatic port pneumatically associated with at least one pneumatic line 520, the at least one internal body 510A, 510B and at least one manual pneumatic pump 800 as illustrated in figure 9.

[0094] In this embodiment, the pneumatic line connects both first 510A and second 510B bellows, which receives air coming from the pneumatic hose 830 of the regular manual pneumatic pump 800, by pumping the insufflation bulb 810. In order to bring the at least one internal body 310 back to the resting condition, the pneumatic valve 820 must be opened.

[0095] In this embodiment, the pulse oximeter device 40 has a built-in display 420 powered by a battery, for displaying the measured pulse rate and / or blood oxygen saturation.

[0096] EMBODIMENTS OF THE METHOD

[0097] According to another embodiment of the present invention, as illustrated by the flowchart of figure 10, it is disclosed a method 1000 of self-calibration of a pulse oximeter device 10, 20, 30, 40, 50.

[0098] Self-calibration is the process in which the pulse oximeter device 10, 20, 30, 40, 50 adjusts its readings to ensure that it provides accurate measurements regardless of individual user variations or conditions of use. This process is based on principles of spectrophotometry and photoplethysmography, which measure the absorption of light at different wavelengths to determine oxygen saturation SpO2. Red light (substantially in the wavelength range of 660 nm) and infrared light (substantially in the wavelength range of 940 nm) are used to distinguish oxygenated hemoglobin HbO2from deoxygenated hemoglobin Hb, while algorithms compensate for factors that may interfere with the accuracy of measurements.

[0099] For pediatric users, calibration needs to address specific anatomical and physiological characteristics, such as reduced skin thickness, higher proportion of fetal hemoglobin HbF, higher heart rate, and greater susceptibility to involuntary movements. The self-calibration algorithm collects and processes user data to automatically adjust saturation calculations by adjusting the photo emitter 300A intensity, photodetector 300B sensitivity, and mathematical models that interpret light absorption (red and infrared light) and integrating data captured by the photodetector 300B with physiological models specific to pediatrics, by using databases that map variations such as skin tones and hemoglobin dissociation curves. It considers anatomical factors (such as skin thickness and capillary density), physiological factors (such as hemoglobin dissociation curve and heart rate), and other external parameters (such as skin pigmentation and the motion of the user). Machine learning algorithms are applied to interpret red and infrared light signals, isolating the pulsatile arterial pulse and correcting for interference. The following specific pediatric factors are accounted for by the self-calibration algorithm.

[0100] Skin Thickness:

[0101] Thinner skin in children reduces fixed light attenuation, but can increase noise due to the relative transparency of the tissues.

[0102] The self-calibration algorithm adjusts the intensity of the photo emitter 300A and calibrates the photodetector 300B gain to optimize the signal-to-noise ratio.

[0103] Skin Color:

[0104] Different pigmentations alter light absorption. The self-calibration algorithm uses specific absorption coefficients for different skin tones, adjusting saturation calculations to compensate for interference from melanin.

[0105] Hemoglobin Dissociation Curve:

[0106] In newborns and infants, the presence of fetal hemoglobin HbF requires adjustments in the saturation modeling which is done by the self-calibration algorithm. HbF has a higher affinity for oxygen, altering the relationship between absorbed light and actual saturation.

[0107] Elevated Heart Rate:

[0108] Children have a higher heart rate than adults. The self-calibration algorithm uses a specific model to isolate the arterial pulse and filter noise from breathing and rapid movements.

[0109] Motion of the user:

[0110] Involuntary movements or shaking are common in children. The selfcalibration algorithm incorporates adaptive filtering features to minimize errors caused by these movements. Tissue Perfusion:

[0111] Perfusion in children may be less stable due to factors such as cold or hypovolemia. The self-calibration algorithm adjusts calculations based on pulsatile intensity measurements to ensure accuracy.

[0112] The method comprises the following steps: i) emitting 1001 light by the photo emitter 300A through at least one blood vessel of a user; ii) detecting 1002 by the photodetector 300B wavelength-related data transmitted through or reflected by the at least one blood vessel; iii.i) self-calibrating 1003 the pulse oximeter device 10, 20, 30, 40, 50 based on the wavelength-related data, in accordance with the self-calibration algorithm accounting for one or more among the differences of skin thickness, skin color variations, hemoglobin dissociation curve, motion of the user, and tissue perfusion.

[0113] The method 1000 further comprising the following sub steps: iii.ii) when accounting for the differences of skin thickness, adjusting the intensity of the photo emitter 300A and calibrating the photodetector 300B gain to optimize a signal-to-noise ratio; iii.iii) when accounting for the skin color variations, using specific absorption coefficients for different skin tones to adjust saturation calculations compensating for interference from melanin; iii.iv) when accounting for the hemoglobin dissociation curve, adjusting a saturation modeling accounting for the presence of fetal hemoglobin HbF; iii.v) when accounting for the motion of the user, applying adaptive filtering features to compensate for reading errors resulting from the motion. iii.vi) when accounting for the tissue perfusion, adjusting calculations based on pulsatile intensity measurements to ensure accuracy.

[0114] The method 1000 further comprising the following steps: iv) sending 1004 the calibrated wavelength-related data to a data processing unit in order to obtain pulse rate and / or blood oxygen saturation data; v.i) displaying 1005 the pulse rate and blood oxygen saturation data in a built-in interface 420; and / or v.ii) sending 1006 the pulse rate and blood oxygen saturation data to be displayed in a remote device.

[0115] The method 1000 steps 1001 to 1006 are stored in a non-transitory computer-readable storage medium, as a set of instructions that when executed by the computer processor, cause the processor to perform at least the step iii.i) 1003 of the method 1000. The processor may also perform the remaining method steps and substeps. The present invention may be embodied in other specific forms without departing from its essential characteristics. The described embodiments are to be considered in all respect only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

[0116] TABLE 1 : LIST OF REFERENCE SIGNS

Claims

SET OF CLAIMS1. PULSE OXIMETER DEVICE (10, 20, 30, 40, 50), characterized by comprising:- an external body (100);- at least one internal body (110, 210, 310, 410A, 410B, 51 OA, 51 OB);- a photo emitter (300A);- a photodetector (300B); wherein the photo emitter (300A) and the photodetector (300B) are positioned in the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) opposed to each other, and wherein the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) is configured to be inflated and deflated.

2. PULSE OXIMETER DEVICE (10, 20, 30, 40, 50), according to claim 1 , characterized in that when the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) is deflated, a distance (D1 ) between the photo emitter (300A) and the photodetector (300B) is increased and when the at least one internal body (110, 210, 310, 410A, 410B, 510A, 51 OB) is inflated, a distance (D2) between the photo emitter (300A) and the photodetector (300B) is decreased.

3. PULSE OXIMETER DEVICE (10, 20, 30, 40, 50), according to any one of claims 1 to 2, characterized by the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B) being inflated by means of a manual pneumatic pump (800) or at least one electronic pneumatic pump (440).

4. PULSE OXIMETER DEVICE (10, 40), according to any one of claims 1 to 3, characterized by the external body (100) having a closed loop shape.

5. PULSE OXIMETER DEVICE (20), according to any one of claims 1 to 3, characterized by the external body (100) having a cuff shape with an open end (220).

6. PULSE OXIMETER DEVICE (30), according to any one of claims 1 to 3, characterized by the external body (100) having a cuff shape with a closable end.

7. PULSE OXIMETER DEVICE (30), according to claim 6, characterized by the closable end being closed by a strap (320).

8. PULSE OXIMETER DEVICE (30), according to any one of claims 6 to 7, characterized by the strap (320) closing the closable end by means of a hook-and- loop fastener or magnetic fastener.

9. PULSE OXIMETER DEVICE (10, 20, 30), according to claim 1 ,characterized by the at least one internal body (110, 210, 310) when inflated, reduces a distance between a geometric centerline (C) of the pulse oximeter device (10, 20, 30) and said internal body (110, 210, 310) in all directions from the centerline (C).

10. PULSE OXIMETER DEVICE (40), according to claim 1 , characterized by the at least one internal body (410A, 410B) having a dome shape.11 . PULSE OXIMETER DEVICE (50), according to claim 1 , characterized by the at least one internal body (510A, 510B) having a bellow shape.

12. PULSE OXIMETER DEVICE (10, 20, 30, 40, 50), according to claim 3, characterized by comprising at least one pneumatic port (120A) pneumatically associated with at least one among:- at least one pneumatic line (520);- the at least one internal body (110, 210, 310, 410A, 410B, 510A, 510B).- the at least one electronic pneumatic pump (440) or the manual pneumatic pump (800).

13. METHOD (1000) OF SELF-CALIBRATION OF A PULSE OXIMETER DEVICE (10, 20, 30, 40, 50), the method being characterized by comprising the following steps: i) emitting (1001 ) light by a photo emitter (300A) through at least one blood vessel of a user; ii) detecting (1002) by a photodetector (300B) wavelength-related data transmitted through or reflected by the at least one blood vessel; iii.i) self-calibrating (1003) the pulse oximeter device (10, 20, 30, 40, 50) based on the wavelength-related data, in accordance with a self-calibration algorithm accounting for one or more among the differences of skin thickness, skin color variations, hemoglobin dissociation curve motion of the user, and tissue perfusion.

14. METHOD (1000), according to claim 13, characterized by further comprising the following sub steps: iii.ii) when accounting for the differences of skin thickness, adjusting the intensity of the photo emitter 300A and calibrating the photodetector 300B gain to optimize a signal-to-noise ratio; iii.iii) when accounting for the skin color variations, using specific absorption coefficients for different skin tones to adjust saturation calculations compensating for interference from melanin; iii.iv) when accounting for the hemoglobin dissociation curve, adjusting asaturation modeling accounting for the presence of fetal hemoglobin HbF; iii.v) when accounting for the motion of the user, applying adaptive filtering features to compensate for reading errors resulting from the motion. iii.vi) when accounting for the tissue perfusion, adjusting calculations based on pulsatile intensity measurements to ensure accuracy.

15. NON-TRANSITORY COMPUTER-READABLE STORAGE MEDIUM, characterized by comprising a set of instructions stored therein that when executed by a computer processor, cause the processor to perform at least the step iii.i) (1003) of the method (1000) as defined in any one of claims 13 to 14.

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