Patent Application
20050226307
This invention relates generally to apparatus for electronically measuring the temperature of a living body, and more particularly, to a thermometer that exhibits enhanced conformity to the anatomy of a human being, especially in and around the mouth.
The basic mercury thermometer has been the standard for measuring body temperature for decades and is known virtually throughout the world. It consists of a hollow glass rod with a bulb of mercury at one end and a temperature scale along the glass rod. Typically, it is inserted into the mouth of a human being and is left in place for three or more minutes. Errors can of course be made in reading the temperature from the scale. Care and a certain amount of patience and expertise are required for proper and accurate use.
From the patient's viewpoint, this form of thermometer is awkward because the thermometer must be held under the tongue and the linear probe is uncomfortable. Anatomically, human beings have a spot under the tongue, often referred to as the hot spot, located on the floor of the mouth, under the tongue, in the rear portion of the mouth. Oral temperature readers target this area of the mouth. The temperature sensing tip of the oral thermometer must be held in the proper position under the tongue. However, the straight thermometer probe is uncomfortable to hold in place at the proper position and is often dislodged by the patient when the patient shifts the probe around inside the mouth in an attempt to ease the discomfort caused by the linear probe. This dislodging of the temperature sensing tip from the correct position increases the time it takes to get an accurate reading.
Electronic thermometers have been introduced which emulate the linear structure of the basic mercury thermometer. A numerical display is usually disposed on electronic thermometers to assist in reading the measured temperature. Electronic thermometers also avoid any potential mercury exposure issues associated with a mercury thermometer. However, these linear electronic thermometers exacerbate the problems of keeping the tip of the thermometer in proper position under the tongue due to the increased weight and mass of the enlarged housing at the opposite end of the thermometer. This problem can be particularly acute in patients unused to, or uncooperative in, having their temperature taken, such as children or the elderly.
Infrared thermometers have been introduced into the market place. Typically, these types of thermometers are designed to measure a person's temperature tympanically, that is, inside the ear canal of a patient. Infrared technology allows a thermometer to take a temperature reading with great speed, often in mere seconds. However, in order to take the temperature reading accurately, the temperature sensing tip of the device must be precisely placed in the correct position within the ear canal. The infrared sensing device and the temperature sensing end of the ear infrared thermometers generally must be positioned at a correct angle (that could be different from person to person) in order to project the infrared beam directly on the tympanic membrane, i.e., the otic hot spot. Since the otic hot spot cannot be seen or felt by the patient or caregiver during the process of taking the temperature, it is difficult to be sure that the temperature is accurately read.
Additionally, ear infrared temperature thermometers are constructed and calibrated such that the temperature sensing end of the probe must be a defined distance away from the ear drum in order for the infrared sensing beams to properly bounce off of the target area in the ear and back to the sensing tip of the probe to ultimately produce an accurate reading. Precise positioning (angle of tip and distance from hot spot) of the thermometer within the ear of a patient may be difficult to achieve. Because these ear thermometers tend to be invasive and difficult to position correctly within the ear, the speed and accuracy of reading the temperature of the patient is often compromised. Moreover, the designs of these tympanic thermometers often are bulky, difficult to use and may produce inaccurate and irregular readings of temperature. In some ear thermometers, the temperature sensing probe is relatively large and thus may be uncomfortable to place inside the ear, especially when the patient is suffering from an ear ailment that renders the inner and/or outer ear painful and sensitive to the touch.
The present invention provides an oral thermometer with improved positioning of the temperature-sensing tip under the tongue of a patient combined with infrared temperature taking technology to provide accuracy and speed to the temperature reading and comfort to the patient. A temperature-sensing tip is disposed to be positioned under the tongue of a patient and in contact with the floor of the mouth and the temperature taking device utilizes infrared technology at the temperature sensing tip.
In one aspect, the present invention features a thermometer that includes a housing constructed to be held by a user; a probe, extending from the housing, having an insertable portion constructed for insertion into the mouth of a patient; an infrared sensor, mounted on the probe, for obtaining data indicative of the patient's temperature; and a spacer, surrounding the insertable portion of the probe, the spacer being configured to preset the distance from the infrared sensor to the oral hot spot of the patient.
Some implementations include one or more of the following features. The thermometer also includes a metal tube extending from a first end adjacent the sensor to a second end between the sensor and an end of the insertable portion. The length of the spacer, measured from the second end of the tube to the end of the insertable portion, is from about 6 to 30 mm. The spacer is formed of a clear plastic, e.g., polycarbonate. The total length of the thermometer inserted into the patient's mouth during use is about 40 to 60 mm, e.g., about 50 mm. The outer diameter of the spacer is from about 4 to 12 mm. The spacer has an angled tip.
In another aspect, the invention features using the thermometers described herein to take the temperature of a patient. For example, the invention features a method of measuring the temperature of a patient, including providing a thermometer including (a) a probe having an insertable portion constructed for insertion into the mouth of the patient, (b) an infrared sensor, mounted on the probe, for obtaining data indicative of the patient's temperature, and (c) a spacer, surrounding the insertable portion of the probe, the spacer being configured to preset the distance from the infrared sensor to the oral hot spot of the patient; and inserting the insertable portion into the mouth of the patient. The thermometer may further include a digital display that displays the data obtained by the sensor, and the method may include reading the display.
Some implementations include one or more of the following advantages. Because the oral hot spot can be seen and felt by the patient or caregiver, the caregiver can easily properly position the infrared sensor in relation to the hot spot. The spacer will preset the distance from the infrared sensor to the oral hot spot, to calibrate the electronics for a highly accurate reading. The tip of the spacer can be placed directly on the hot spot so the patient can be sure that the thermometer probe is correctly positioned, assuring an accurate temperature reading. Because the probe can be readily correctly positioned, generally the caregiver will not need to take several readings to corroborate the temperature data. Because the area of the oral hot spot is relatively large and the angle of the probe is predetermined by the spacer, an accurate temperature reading can be readily obtained. The spacer can be made from clear material, such as polycarbonate, to allow the infrared beam to pass through the spacer material and bounce off the oral hot spot. Due to the oral nature of this thermometer, it is not necessary to touch an ear that may be inflamed or sensitive due to ear infection or other ailment. A temperature reading can be obtained quickly, e.g., within one second or less, and with minimum discomfort to the patient.
The term “patient,” as used herein, refers to any human being or mammal whose temperature is to be taken, in any setting, regardless of whether the patient is sick or well. The temperature may be taken by the patient him or herself, or by a caretaker, e.g., a nurse, physician, or family member.
Other features and advantages of the present invention will be apparent from the description and drawings, and from the claims.
a-4d are sectional views of several alternative configurations of an integral spacer and sensing tip of the infrared oral thermometer probe;
The various drawing figures will now be referred to in detail. Turning first to
As can be seen in
The oral thermometer also includes a spacer 12 within the tip of the sensing probe (best seen in
The outer diameter of the spacer is selected to be large enough for the infrared ray to pass through, but not so large that the spacer is uncomfortable in the patient's mouth. Generally, the outer diameter will be from about 4 to 12 mm, e.g., about 5 to 7 mm.
Preferably, the spacer is made of polycarbonate or other transparent plastic, so that the infrared beam may pass through the spacer and bounce off of the oral hot spot. The material should be hard enough so that it cannot be bitten through by the patient. The inner wall of the spacer should be relatively straight (in the axial direction) so that the infrared ray is not obstructed. The spacer may have any desired cross-sectional shape, e.g., circular, oval or elliptical. Preferably the edges of the probe have a curvature to enhance patient comfort.
a-4d depicts several embodiments of the temperature sensing probe with differing sensing tip shapes that conform to the anatomy of the patient's mouth and fit comfortably on the hot spot in a person's mouth. As shown, the tip may be angled (
Referring to
