Over the past two decades, the Accreditation Council for Graduate Medical Education (ACGME) has been steadily limiting trainees' work hours, specifying the frequency of overnight calls, consecutive hours a trainee can work and necessary time off. Individual providers' ability to perform in clinical situations, and patient outcomes, have been shown to be negatively impacted by sleep deprivation. The ACGME reform has transformed medical education in a way that has restricted opportunities to learn and achieve competence in the clinical field. The new generation of physicians exhibit essential scientific knowledge, but have limited exposure to critical clinical situations.
Simulation has long been used and proven effective in the aviation and nuclear power industries, and has been used more recently in medicine. The simulation method of teaching has become an integral part of educational curricula in medical fields to improve technical proficiencies and decrease medical errors. Southgate W M and Annibale D J, Adv Neonatal Care. 2010; 10(5):261-268; Cates L A, Wilson D, Adv Neonatal Care. 2011; 11(5):321-327. However, existing training models and methods lack many essential elements, and thus make it impossible to adequately train medical professionals to successfully conduct medical procedures on a subject. For example, existing training modes are not capable of stimulating the removal of gas and fluid from a subject and do not contain anatomically correct and operable simulated organs or structures. See Gupta A O, Ramasethu J. Pediatrics. 2014, 134 (3) e798-e805.
The neonatal population, both term and preterm, presents challenges with the need for technical precision due to the patients' unpredictability and small size. Gozzo Y, Mercurio M R, NeoReviews. 2009; 10(2):e82-e88. Thoracostomy tube insertion is a procedure that is widely used in critical care areas. Kesieme E B, et al. Pulmonary Medicine. 2012. Thoracostomy is a procedure for draining air and/or fluid from the chest of a subject. Pneumothorax occurs most commonly in the newborn period and is often an emergent and life saving intervention. Although there is a higher incidence of pneumothoraces in preterm infants than term, many sick term infants can present with conditions such as meconium aspiration syndrome, hydrops fetalis, chylothorax, lung hypoplasia, and pneumonia that put them at a higher risk for requiring the need for chest tube placements as well. Aly H, et al., The Journal of Maternal-Fetal & Neonatal Medicine. 2014; 27(4):402-406.
Aside from pneumothoraces, other conditions that require the placement of chest tubes include pleural effusions and chylothoraces. Chylothorax is the most common effusion in the newborn period. Depending on the etiology, it is a condition often requiring repetitive drainage with multiple chest tubes. Complications include: malposition, lung impalement/perforation, infection, scarring, bronchopulmonary fistula, hemorrhage, nerve damage, cardiac perforation, and death. Kesieme E B, et al. Pulmonary Medicine. 2012; 2012:256878.
There are more than 1000 Neonatal Intensive Care Unit's (NICU) in United States with approximately 5200 practicing NNP's, and 4200 Neonatologist. There are also Hospitalist, Pediatricians or Physician extenders, all of who provide newborn care at different levels of nurseries and NICU's. Thus, it is important that these providers receive training to recognize and perform the procedure. Adequate training, however, has not been available. Hence, there is a pressing need for adequate training in neonatology. Specifically, chest tube placement in infants, although lifesaving, can have serious complications, including death. Necessary invasive skills can be simulated with task trainers to train health care providers. However, although a spectrum of technology and computerized training can simulate real life situations, there is no task trainer currently available that can provide simulation for neonatal patients for the procedures of thoracotomies with chest tube placement for pneumothorax or pleural effusions.
Hence, there is a need for an anatomically correct and operable training model that can be used to emulate naturally occurring pathophysiological conditions and to train clinicians to effectively treat such conditions. For example, existing training devices do not include a pericardial sac surrounding a heart or lungs that can be filled with fluid and or air which are surrounded by anatomically correct structures such as a plurality of ribs. Hence, existing devices cannot adequately emulate the human (e.g., infant) body to enable a care-giver to adequately train for an invasive procedure.
Embodiments of the present disclosure provide devices and methods that address the above clinical needs.
The present disclosure is directed to an anatomically correct model capable of simulating bodily structures, the feel of such structures and the environment surrounding the structures. The anatomical model of the present disclosure overcomes the deficiencies of existing training models, in part through the inclusion of certain physiologically relevant elements that are necessary to simulate the chest cavity of a human, such as an infant. In fact, the use of the disclosed anatomically correct model resulted in over 90% of the users being able to completely and accurately perform a simulated medical procedure.
As such, in one aspect of the present disclosure an anatomically correct model is provided. In certain embodiments, the anatomical model includes a plurality of simulated of bodily structures. In some embodiments, the plurality of simulated bodily structures includes a thorax. In specific embodiments, the thorax can include an internal cavity and a plurality of ribs. In some embodiments, the internal cavity can also include a heart that is operably connected to the model. In certain embodiments, the heart includes a pericardial sac that substantially surrounds the heart. In a specific embodiment, the anatomically correct model of the present disclosure includes a pericardial sac that can be filled with a fluid or other material.
In other embodiments, the plurality of simulated bodily structures includes at least one membranous layer. The membranous layer includes at least one elastomeric layer that covering at least a portion of an anterior aspect of the thorax and a posterior aspect of the thorax. In specific embodiments, the at least one simulated membrane layer includes a skin layer. In some embodiments, the skin layer can be removed and replaced by, for example, affixing or removing the skin layer to a means for connecting the skin layer to an outer surface of the model. In yet another embodiment, the at least one membranous layer includes a skin layer and at least one other layer, such as a muscle layer or a subcutaneous (adipose or tissue) layer. In certain embodiments, the at least one membranous layer includes a skin layer, a subcutaneous layer and a muscle layer.
In some embodiments, the plurality of bodily structures of an anatomical model of the present disclosure includes at least one chamber such as a lung. In some embodiments, the plurality of simulated bodily structures includes two lungs. In another embodiment, the model includes at least one lung that can be illuminated and expanded (inflated or deflated) by a user. In specific embodiments, the at least one lung is located within an internal cavity of the thorax of such model. For example, in some embodiments, the lung includes at least one bronchus that is operably connected to a lung and the lung is also connected to the trachea within the internal cavity of the model, such that the trachea operably connects to at least one bronchus. In other embodiments, the plurality of simulated bodily structures includes at least one chamber, which can be filled with fluid or air to emulate the space surrounding a lung in the internal cavity (e.g., pleural cavity). In other embodiments, the plurality of simulated bodily structures includes at two chambers, each of which are located in the internal cavity of the thorax. In one embodiment, at least one chamber is filled with air to emulate a pneumothorax. In other embodiments, at least one chamber is filled liquid to emulate a pleural effusion.
In another aspect of the present disclosure, a method for using the disclosed anatomical model is provided. In certain embodiments, the anatomically correct model of the present disclosure can be used to simulate chest tube placement in a subject, such as a human. In some embodiments, the methods of the present disclosure include simulations of the timing, preparation, technique and incisions included in the placement of a chest tube. In specific embodiments, the methods of the present disclosure include one or more of the following techniques, making a subcutaneous tract in a subject, perforating a pleural cavity, placement (insertion) of a chest tube in a subject, draining air or fluid from the thorax of a subject, suturing a tube in a subject and providing sterile dressing to affected sites of the subject.
In some embodiments, the anatomically correct model of the present disclosure is used to emulate a subject in need of thoracostomy tube insertion. In one embodiment, an anatomical model of the present disclosure can be used to simulate a subject having a cardiac tamponade. In specific embodiments, the anatomical model can be used to simulate pericardiocentisis in cardiac tamponade from a pericardial effusion or pneumopericardium of a subject. In other embodiments, the anatomical model can be used to simulate pneumothorax in a subject, such as an infant. In certain embodiments, the model can be used to emulate conditions found in a human infant diagnosed with respiratory distress syndrome, meconium aspiration syndrome, hydrops fetalis, chylothorax, lung hypoplasia, and pneumonia.
The present disclosure will be better understood by reference to the following drawings, which are provided as illustrative of certain embodiments of the subject application, and not meant to limit the scope of the present disclosure.
In the discussion and claims herein, the terra “about” indicates that the value listed may be somewhat altered, as long as the alteration does not result in nonconformance of the process or device. For example, for some elements the term “about” can refer to a variation of +0.1%, for other elements, the term “about” can refer to a variation of ±1% or ±10%, or any point therein.
As used herein, the term “substantially”, or “substantial”, is equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result. For example, a surface that is “substantially” flat would either completely flat, or so nearly flat that the effect would be the same as if it were completely flat.
As used herein terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration.
As used herein, terms defined in the singular are intended to include those terms defined in the plural and vice versa.
References in the specification to “one embodiment”, “certain embodiments”, some embodiments” or “an embodiment”, indicate that the embodiment(s) described may include a particular feature or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. For purposes of the description hereinafter, the terms “upper”, “lower”, “right”, “left”, “vertical”, “horizontal”, “top”, “bottom”, and derivatives thereof shall relate to the invention, as it is oriented in the drawing figures. The terms “overlying”, “atop”, “positioned on” or “positioned atop” means that a first element, is present on a second element, wherein intervening elements interface between the first element and the second element. The term “direct contact” or “attached to” means that a first element, and a second element, are connected without any intermediary element at the interface of the two elements.
Reference herein to any numerical range expressly includes each numerical value (including fractional numbers and whole numbers) encompassed by that range. To illustrate, reference herein to a range of “at least 50” or “at least about 50” includes whole numbers of 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, etc., and fractional numbers 50.1, 50.2 50.3, 50.4, 50.5, 50.6, 50.7, 50.8, 50.9, etc. In a further illustration, reference herein to a range of “less than 50” or “less than about 50” includes whole numbers 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, etc., and fractional numbers 49.9, 49.8, 49.7, 49.6, 49.5, 49.4, 49.3, 49.2, 49.1, 49.0, etc.
This disclosure is directed to an anatomically correct model that includes a plurality of simulated bodily structures. Each of the plurality of simulated body structures are at least substantially anatomically correct and are each formed of materials that substantially correlate to the natural structure and feel of their corresponding anatomical elements. For example, a skin layer can include a silicon material or mesh or fabric that emulates the feel, structure and consistency of a human dermal layer. In one instance, an adipose layer can be composed of a gelatin having a consistency and thickness that emulates that of a human. Other materials and their corresponding organs or structures, which can be used in the models of the present disclosure, will be known by one of ordinary skill in the art.
The disclosed anatomical model can include several components, including a thorax forming an internal cavity, with a heart, at least one lung and a trachea located within the internal cavity and an at least one membranous layer that substantially covers the exterior surface of the thorax.
As shown in
The anterior portion (4) and the posterior portion (6) of the thorax (2) form an internal cavity (8), which can then be surrounded, in whole or in part, by a plurality of ribs (10). As shown in
For example, the intercostal spaces (12) between each of a plurality of ribs (10) are substantially the same size as those found in an infant human, which has a weight of about 0.5 kg to about 3.5 kg, from about 1 kg to about 3.5 kg. Also, the skeletal structure of the model 1 can be substantially the same as the chest wall diameter and length of the thorax of an infant human which is between the weights of about 0.5 kg and about 3.5 kg. In some embodiments, the size of the human infant that is being emulated by the present model is an infant having a weight of between 0.5 kg to 3.5 kg, 1.0 kg to 3.5 kg, 0.5 kg to 3.0 kg, 1.0 kg to 3.0 kg, 0.5 kg to 2.5 kg, 1.0 kg to 2.5 kg, 0.5 kg to 2.0 kg, 1.0 kg to 2.0 kg, 0.5 kg to 1.5 kg, or 0.5 kg to 1.0 kg. In other embodiments, the size of the human infant that is being emulated by the present model is an infant having a weight of about 0.5 kg, 0.6 kg, 0.7 kg, 0.8 kg, 0.9 kg, 1.0 kg, 1.1 kg, 1.2 kg, 1.3 kg, 1.4 kg, 1.5 kg, 1.6 kg, 1.7 kg, 1.8 kg, 1.9 kg, 2.0 kg, 2.1 kg, 2.2 kg, 2.3 kg, 2.4 kg, 2.5 kg, 2.6 kg, 2.7 kg, 2.8 kg, 2.9 kg, 3.0 kg, 3.1 kg, 3.2 kg, 3.3 kg, 3.4 kg, or 3.5 kg. Thus, the anatomically correct model (1) of the present disclosure can be of a structure that imitates a human infant's skeletal and organ structure can be used for training procedures on human infant medical procedures. For example, and as shown in the exemplary embodiment set forth in
Further, as shown in
As shown in
In the specific embodiment, exemplified in
In one embodiment, the at least one membranous layer (16) includes at least two layers or at least three layers. In certain embodiments, the at least one membranous layer (16) includes a skin layer (18), which is composed of a silicon material in a manner that mimics the elasticity, structure and density of the human dermis. In other embodiments, the at least one membranous layer (16) includes a subcutaneous layer (20) composed of a gel and/or silicon that emulates the density, elasticity and structure of human fat (adipose) and/or subcutaneous tissue. In certain embodiments, the anatomically correct model (1) of the present disclosure includes a muscle layer (22) that emulates the density, elasticity and structure of human muscle tissue. In specific embodiments, the model of the present disclosure includes an at least one membranous layer (16) having a skin layer (18) and a subcutaneous layer containing one or more of an adipose layer (20) and/or one or more of a subcutaneous tissue layer. In some embodiments, of the present disclosure the anatomically correct model (1) has an at least one membranous layer (16) that includes a skin layer (18) and a subcutaneous layer containing an adipose layer (20) and a muscle layer (22). See, for example,
In some embodiments; the skin layer (18) can be adhered to the topmost surface of the subcutaneous layer (e.g., adipose layer (20)) or a muscle layer (22). In instances where the anatomically correct model (1) has a membranous layer (16) that includes a skin layer (18) and a subcutaneous layer containing an adipose layer (20) and a muscle layer (22), the skin layer (18) is adhered to the topmost surface of the subcutaneous layer (20). For example, the skin layer (18) is adhered to the topmost surface of the adipose layer (20), and the bottommost surface of the adipose layer (20) is adhered to a topmost surface of a muscle layer which is then adhered to the outermost surface of the thorax (2). One example of how the at least one membranous layer (16) of the present disclosure is formed is discussed in Example 1, below.
In other embodiments, such as that shown in
In embodiments of the disclosed model, such as that shown in
The various embodiments of the present disclosure that include subcutaneous layers comprising different material layers, enable a user to practice medical techniques including, but not limited to, those that include traversing the at least one needle layer, with a tube or needle. For example, needle aspiration through membranous layer (16) for pneumothorax relief; needle aspiration through membranous layer (16) for a pleural effusion treatment; chest tube placement through intercostal spaces (12) including simulation of injection of an analgesic (e.g. lidocaine) or anesthetic into the membranous layer (16); incising the membranous layer (16) to create a subcutaneous tract and/or tunnel in the membranous layer (16) into the pleural cavity; maneuvering of the a tube anteriorly or posteriorly in the internal cavity (8); suturing a chest tube to the membranous layer (16); and applying appropriate dressing to the exposed surface of a membranous layer (16).
Although not shown to scale in
In some embodiments, the skin layer (18) is between 0.5 mm and 1.5 mm thick. In yet other embodiments, the skin layer (18) is between 0.75 mm and 1.25 mm, 0.75 and 1.0 mm, or 0.5 and 1.0 mm thick. In certain embodiments, the skin layer (18) is about 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm or about 1.0 mm thick. The foregoing skin layer thicknesses are important to emulate the thickness, density and elasticity of the human dermis.
In some embodiments, the muscle layer (22) is between 0.5 mm and 1.5 mm thick. In yet other embodiments, the muscle layer (22) is between 0.75 mm and 1.25 mm, 0.75 and 1.0 mm, or 0.5 and 1.0 mm thick. In certain embodiments, the muscle layer (22) is about 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm or about 1.0 mm thick. The foregoing muscle layer thickness are important to emulate the thickness, density and elasticity of human muscle tissue, specifically that of an infant.
In certain embodiments, the subcutaneous layer contains an adipose layer (20) that can be can be formed in a manner and location that allows for a simulated subcutaneous tunnel or tract to be formed traversing the layer. This tunnel or tract provides a means for inserting a chest tube through the muscle layer (22) into the internal cavity (8) of the model (1) by an operator.
Referring to
In other embodiments and as shown in
As seen in
For example, as shown in
As shown in
Moving to
In one embodiment, the anatomically correct model (1) of the present disclosure includes a simulated diaphragm (29), as shown in
As set forth above, the model (1) of the present disclosure can be used to practice several medical interventions and procedures on an anatomically correct device that emulates the real life clinical conditions faced by clinicians. More specifically, using the disclosed model, operators will be able to simulate the methodology for, amongst other actions, proper chest tube placement.
As such, in certain aspects of the present disclosure, a method for using the disclosed model for simulations of, for example, preparation, time out, sterile technique, incision, making a subcutaneous tract, perforating into pleural space, placement of a chest tube, draining air or fluid, suturing the chest tube and dressing the site. The disclosed model can also be used to simulate pericardiocentesis in cardiac tamponade or pneumopericardium.
For example, the anatomically correct model of the present disclosure can be used to practice the following procedures: positive pressure ventilation (PPV) with lung (24) inflation (see
The methods and model of the present disclosure will be better understood by reference to the following Examples, which are provided as exemplary of the disclosure and not in any way limiting.
An anatomically correct simulated membranous layer (16) of the present disclosure was fabricated using commercially available products from Smooth-On, Inc.™. The skin layer (18) was made using Ecoflex® 00-30, a platinum catalyzed silicone. The silicone material layer was brushed into a mesh fabric and allowed to cure. See
When creating skin for a larger subject such as a full term neonatal infant (3.5 kg in weight), a second adipose layer (20a) can be formed on the topmost surface of the first adipose layer (20) as described above.
This membranous layers (16, 20, 22) then is of such a structure, density and elasticity so as to simulate at least one naturally occurring physical characteristic that can be sensed by an operator performing a procedure on a human person. For example, the “pop” and tension felt by an operator of the model when inserting a chest tube through the membranous layer (22) simulates the same process conducted in a human subject.
One model of the present disclosure is formed to include anatomically correct skin (18) and subcutaneous tissue (20) affixed to an underlying plurality of ribs (10). Here the model includes an anatomically correct rib cage and intercostals spaces (12), based on actual clinical measurements of both 1.04.5 kilogram (kg) and 3.0-3.5 kg human infant subjects. The ribs (10) and additional elements of the thorax are fabricated with resin by additive manufacturing using 3D printing methods. This creates a precise and anatomically correct model, such as that shown in
The rib cage of the model is then wrapped in a constructed translucent membranous layer (16) including a skin layer (18), which is tightly secured to pegs (not shown). This permits the visualization and palpation of the ribs, which aids in identifying the placement for thoracostomy tubes. See
The model also includes space occupying chambers (31) for air and fluid (e.g., balloon or condom), which are important for training clinician to properly insert a chest tube in a subject. See
Also, a pericardial sac (15) is created surrounding a foam/clay shaped heart located in the internal cavity (8) of the thorax using a latex balloon (e.g., condom) that is capable of being filled with a fluid or gas. See
A model affixed to an angled support (27) was created and tested, as shown in
A model that includes a diaphragm (29) located within the internal cavity (8) of the thorax (2) as formed and tested. See
The described embodiments and examples of the present disclosure are intended to be illustrative rather than restrictive, and are not intended to represent every embodiment or example of the present disclosure. While the fundamental novel features of the disclosure as applied to various specific embodiments thereof have been shown, described and pointed out, it will also be understood that various omissions, substitutions and changes in the form and details of the devices illustrated and in their operation, may be made by those skilled in the art without departing from the spirit of the disclosure. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the disclosure. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the disclosure may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. Further, various modifications and variations can be made without departing from the spirit or scope of the disclosure as set forth in the following claims both literally and in equivalents recognized in law.
The present application claims benefit of United States Provisional Applications 62/410,163 filed on Oct. 19, 2016 and 62/519,610 filed on Jun. 14, 2017, the contents of both of which are incorporated by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2017/057101 | 10/18/2017 | WO | 00 |
Number | Date | Country | |
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62410163 | Oct 2016 | US | |
62519610 | Jun 2017 | US |