PATENT ABSTRACT
An apparatus to provide a regulated pressurized gas for introduction into the body of a patient during a medical procedure comprises an internal flow path through which to convey the pressurized gas, a regulator in the flow path to regulate the pressurized gas, and a biosensor to detect a body substance entering or in proximity to the flow path.

PATENT DESCRIPTION
FIELD OF THE INVENTION  
       [0001]     At least one embodiment of the present invention pertains to equipment used for endoscopic medical procedures, and more particularly, to an advanced insulator for endoscopy.  
       BACKGROUND  
       [0002]     Endoscopy in the medical fields allows internal structures of a patient&#39;s body to be viewed without the use of traditional, fully-invasive surgery. Endoscopy is widely used to perform many types minimally-invasive medical procedures, such as arthroscopy, laparoscopy, gastroscopy, colonoscopy, etc. A basic tool of endoscopy is the endoscope (“scope”), which contains a set of optics through which internal features of a patient&#39;s body can be viewed (typically, with the aid of a special-purpose video camera attached to the endoscope and an appropriate video monitor), when the endoscope is partially inserted into the patient&#39;s body.  
         [0003]     A supporting device commonly used in certain forms of endoscopy is an insulator. An insufflator is an electromechanical device which pumps sterile gas, typically carbon dioxide, into the body of the patient in the region where the scope is inserted. The purpose is to create more space within the body cavity for the surgeon to see anatomical features and manipulate his instruments. An insulator is commonly used in laparoscopy, for example.  
         [0004]     The primary components(s) in a conventional insufflator is/are one or more pressure regulators (connected in series if there is more than one) to regulate the pressure level of the gas. In general, a regulator includes a valve and electrical/electronic circuitry to control opening and closing of the valve. For example, the circuitry may be implemented in the form of a “stepper motor” to actuate the valve. The insufflator receives pressurized gas from an external gas canister though an external flexible gas conduit and outputs the regulated, pressurized gas through another (second) external flexible gas conduit. The regulated, pressurized gas is introduced into the body of the patient through a trocar.  
         [0005]     During endoscopic surgery, the pressure within the body occasionally and momentarily may be greater than at the output of the insulator at a particular instant in time. When this happens, gas and/or or biocontamination (e.g., body fluid) can travel back through the external gas conduit toward the insulator (“backflow”). If biocontamination reaches the insufflator, contamination of the insulator can occur, which necessitates a delay in the procedure, possibly putting the patient at greater risk and, at the very least, complicating cleaning and sterilization of the equipment. With conventional insufflators, there is no easy way to determine whether backflow contains biocontamination or merely sterile gas, other than by visual inspection. Visual inspection, however, can be difficult and inaccurate. Some systems use a humidity detector to detect indirectly the possible presence of backflow; however, that is not a very accurate detection method, at least because it cannot directly detect the presence of biocontamination. Among other reasons, a humidity detector cannot reliably detect the presence of biological particulate matter independently of body fluid. There may be other reasons why it may be undesirable to base the detection of biocontamination or backflow on humidity.  
         [0006]     In addition, biocontamination can be present in the gas supply that is input to the insulator. Known conventional insufflators, however, have no way of detecting this mode of biocontamination.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention includes an apparatus to provide a regulated pressurized gas for introduction into the body of a patient during a medical procedure. The apparatus comprises an internal flow path through which to convey the pressurized gas, a regulator in the flow path to regulate the pressurized gas, and a biosensor to detect biocontamination in proximity to the flow path.  
         [0008]     Other aspects of the invention will be apparent from the accompanying figures and from the detailed description which follows.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     One or more embodiments of the present invention are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which:  
         [0010]      FIG. 1  illustrates an example of some of the external features of an insulator, according to certain embodiments of the invention; and  
         [0011]      FIG. 2  is a block diagram showing internal components of an insufflator according to certain embodiments of the invention.  
     
    
     DETAILED DESCRIPTION  
       [0012]     An improved insulator for endoscopy is described. References in this specification to “an embodiment”, “one embodiment”, or the like, mean that the particular feature, structure or characteristic being described is included in at least one embodiment of the present invention. Occurrences of such phrases in this specification do not necessarily all refer to the same embodiment.  
         [0013]     Refer now to  FIG. 1 , which shows an example of some of the external features of an insulator, according to certain embodiments of the invention. The insufflator  1  has a housing  2 , within which are contained one or more pressure regulators and flow rate regulators and other components (not shown in  FIG. 1 ). The housing  1  has a gas input interface  3  at which a flexible gas conduit  4  is connected to receive the gas from an external gas canister (not shown) and a gas output port  5  at which another flexible gas conduit  6  can be connected to provide gas to the patient. Conduit  6  terminates in a trocar  9  or other similar device, which can be considered part of the conduit  6 . Visible on the exterior of the insufflator  1  is the display area  7  of a display unit, which may be, for example, a touchscreen liquid crystal display (LCD) device. Most if not all of the features and functions of the insufflator  1  can be controlled through a graphical user interface (GUI) presented on the display unit. Nonetheless, various other manual controls and/or indicators  8  may also be provided on the exterior of the insufflator  1 , as a secondary way of controlling certain features and functions or as a way to control other features and functions.  
         [0014]      FIG. 2  is a block diagram showing internal components of an insufflator according to certain embodiments of the invention, which can be an insufflator such as shown in  FIG. 1 . The insufflator  20  in  FIG. 2  includes a gas input port  21 , a gas output port  22 , and a gas flow path  23  coupled between the gas input port  21  and the gas output port  22 . In operation, the gas canister that provides the gas supply (not shown) is connected to the gas input port  21 , either directly or indirectly through a gas conduit (e.g., a hose). The insulator  20  further includes a flow controller  24 , pressure controller  25  and a humidifier  26 , coupled in series with each other in the gas flow path  23 . The pressure controller  25  is coupled to the output of the flow controller  24 . The humidifier  26  is coupled to the output of the pressure controller  25 .  
         [0015]     Also connected to the gas flow path  23  between the gas input port  21  and the flow controller  24  are a venting valve  27 , a pressure relief valve  28 , and a check valve  29 ; a heating element  30  to maintain the gas at a predetermined temperature, and an input pressure sensor  31 . Further connected to the gas flow path  23  between the gas output of the pressure controller  25  and the input of the humidifier  26  are an output pressure sensor  32  and an output flow sensor  33 . In addition, coupled to the gas flow path  23  between the gas output of the humidifier  26  and the gas output port  22  are a humidity sensor  34  and a temperature sensor  35 .  
         [0016]     It is desirable to be able to accurately and promptly detect the presence of biocontamination (e.g., from the patient&#39;s body and/or the gas supply) before it can enter the insufflator  20 . Therefore, a first biosensor  44  is provided in the insulator  20  to detect biocontamination in the gas supply that is input to the insufflator  20 , while a second biosensor  45  is also provided in the insufflator  20  to detect biocontamination from the patient (e.g., due to backflow). A “biosensor” in this context is any sensor that can directly detect the presence of biocontamination, such as a body fluid or other body substance or a biological agent (e.g., a microbe). Sensors of this type are available from companies such as Agilent Technologies, Inc. of Palo Alto, Calif.  
         [0017]     Biosensor  44  is positioned to detect biocontamination entering or about to enter the insulator  20  from the gas supply side at the gas input port  21 . As such, biosensor  44  can be located at or just inside the gas input port  21  of the insufflator, as shown, or it can be located outside the insufflator  20  at a convenient location in the external gas supply conduit  4  connected between the gas input port  21  and the gas supply. Biosensor  45  is positioned to detect biocontamination entering or about to enter the insufflator  20  from the gas output side at the gas output port  22 . As such, biosensor  45  can be located at or just inside the gas output port  22  of the insufflator, as shown, or it can be located outside the insulator  20  at a convenient location in the external gas conduit  6  connected between the gas output port  22  and the patient (e.g., in the trocar  9 ).  
         [0018]     When biocontamination is detected by biosensor  44 , biosensor  44  asserts a signal  46  to the control unit  37 , which causes the insufflator  20  to take an appropriate action, which may include any one or more of: outputting an alarm to the user, shutting down the insulator and/or activating some other protection procedure. An alarm in this context may be, for example, an audible and/or visual indication in the GUI and/or a tactile indication to the user. Similarly, when biocontamination is detected by biosensor  45 , biosensor  45  asserts a signal  36  to the control unit  37 , which causes the insulator  20  to take an appropriate action such as mentioned above.  
         [0019]     In embodiments in which biosensor  44  and/or biosensor  45  is external to the insufflator  20 , the biosensor signal input may be received by the insulator  20  via one or more physical signal lines (e.g., through the gas input port  21  and/or gas output port  22  and/or a separate signal interface) or via wireless communication links.  
         [0020]     The humidifier  26  humidifies the gas to help reduce dehydration of the patient that would be caused by introducing an otherwise dry gas into the body cavity. A user can control the humidifier  26  to control the humidity level, through the GUI.  
         [0021]     The insulator  20  further includes a control unit  37  to control the overall operation of the insufflator  20 , including operation of flow controller  24 , pressure controller  25 , heating element  30  and humidifier  26 . The control unit  37  may be or may include, for example, one or more programmable microprocessors or microcontrollers, application-specific integrated circuits (ASICs), programmable logic devices (PLDs), or a combination of such devices or similar types of devices commonly used to control electronic and electromechanical devices. The input pressure sensor  31 , output pressure sensor  32 , output flow sensor  33 , humidity sensor  34  and temperature sensor  35  provide their respective output signals to the control unit  37 , which are used as feedback to control the gas pressure, flow rate, humidity and temperature, respectively.  
         [0022]     The insulator  20  further includes a display unit  38  and various manual input controls  39 , for use as mentioned above, as well as a sound unit  40 , a network unit  41 , memory  42 , and an auxiliary unit  43 . The sound unit  40  provides audible outputs to the user (e.g., feedback sounds to acknowledge user inputs and/or machine-generated spoken prompts). In certain embodiments, the insufflator  20  may include speech recognition capabilities so as to be capable of responding to spoken commands from a user. In that case, the insulator  20  further includes a sound input device such as a microphone (not shown).  
         [0023]     The memory  42  is used to store software and/or data. For example, memory  42  may store software and/or firmware for execution by the control unit  37  to control essentially any function of the insulator  20 . In addition, memory  42  may store various user profiles and settings, parameter profiles, etc. Memory  42  may be, for example, essentially any form of random access memory (RAM), read-only memory (ROM) (which may be programmable), flash memory, or other type of memory, or a combination thereof.  
         [0024]     The network unit  41 , under the control of the appropriately-configured control unit  37 , enables the insufflator  20  to communicate with a remote device or person over a network. The network (not shown) may be, for example, a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a global area network (GAN) such as the Internet, or any combination thereof. The network unit  41  may be, for example, a conventional dial-up modem, a cable or Digital Subscriber Line (DSL) modem, an Ethernet adapter, etc.  
         [0025]     Thus, an improved insufflator for endoscopy has been described.  
         [0026]     Software to implement the techniques introduced here may be stored on a machine-readable medium, such as memory. A “machine-accessible medium”, as the term is used herein, includes any mechanism that provides (i.e., stores and/or transmits) information in a form accessible by a machine (e.g., a computer, network device, personal digital assistant (PDA), manufacturing tool, any device with a set of one or more processors, etc.). For example, a machine-accessible medium includes recordable/non-recordable media (e.g., read-only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; etc.), etc.  
         [0027]     The term “logic”, as used herein, can include, for example, hardwired circuitry, programmable circuitry, software, or any combination thereof.  
         [0028]     Although the present invention has been described with reference to specific exemplary embodiments, it will be recognized that the invention is not limited to the embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative sense rather than a restrictive sense.