Patents on the soles of your shoes...: Oh, patents! Cordless stethoscopes for safe auscultation (1)

Prior to the COVID 19 pandemic, electronic stethoscopes (e.g.; Eko Core, Thinklabs One or Littman 3200) were primarily known and touted for their superior sound quality, sound filtering possibilities (ie.; ambient noise reduction), the benefits of recorded digital data that can be streamed, shared, compared, annotated, forwarded and stored in medical records, and the general portability of the devices with no bulky tubing or earpieces, including their stylish design.

Within the context of the COVID 19 pandemic, Bluetooth-enabled, wireless digital stethoscopes became vital instruments of safety that enabled medical personnel to retain the full protection of their hazmat equipment, while auscultating patients that were infected, or potentially infected.

Interestingly, the following patent US7182733B2, filed Aug. 20, 2003, granted Feb. 27, 2007, titled Cordless stethoscope for hazardous material environments anticipated such threats as contagious diseases spreading through international air travel, coupled with threats of biological and chemical terrorism. Responding to the specific problematic situations of contagious or more generally hazardous environments that require working in hazmat suits, the invention offers safe auscultation, using a cordless stethoscope, equipped with magnetic induction coils for the transmission of auscultatory sounds, and in a later abandoned patent application US20070049838A1 also using radio frequencies. Thus, the inventive auscultation device, whether using magnetic induction or a combination of magnetic induction and radio frequencies, might be used wearing hazmat suits, without breaking any of the protection afforded by the suits, in highly contagious situations. The inventor, Keith Sauerland, specifically states:

It has come to my attention during preparedness training for dealing with these threats that it is impossible for medical personnel to use a standard stethoscope when wearing a HAZMAT suit without compromising the integrity of the suit. Breaking the protective barrier of the HAZMAT suit defeats the purpose of wearing the suit and places medical personnel at risk.

As illustrated in the patent Figure 3 below, the invention stethoscope hardly looks like a conventional stethoscope. However, it is specifically designed for medical personnel wearing hazmat suits (as illustrated to the right with staff using the Spanish eKuore stethoscope). Specifically, the invention stethoscope is equipped with means for sending and transmitting sounds from an auscultation head to receivers within earpieces, or to a receiver clipped inside the hazmat suit. The preferred mode of transmission and reception is magnetic induction. The housing of the auscultation head is of a shape that compensates for any loss of fine motor skills associated with the use of heavy hazmat suit gloves, and it is fluid-tight so that it can be easily decontaminated. The cordless stethoscope is used outside of the hazmat suit to sense and transmit sounds, from the patient’s body, to a receiving device inside the hazmat suit, which converts the sounds into audible sounds that the user of the cordless stethoscope can interpret. Optionally, the cordless stethoscope may also include a microphone designed to capture voiced communication from the patient, which might otherwise not be heard through a hazmat suit.

Below the abstract of this invention, together with the patent Figure 3, showing a cross-sectional view of the sound sensing device 20. In particular the patent Figure 3 illustrates the stethoscope head 30, the fluid-tight casing 70, a power source 80, preferably a dry-cell battery located within the sound sensing device, a transmitter 120, an activation switch 100, inside an activator switch opening 170, with indicator light 210 and indicator light opening 200. The housing 70 has an opening 160 for receiving the stethoscope head 30, comprising a diaphragm 220, and an auscultation bell 230, a low-frequency response microphone 260 for sensing auscultatory sounds produced by the patient, a first fluid-tight cover 240 and fluid-tight members 250 connecting the stethoscope head 30 and opening 160 to maintain the fluid integrity of the housing 70, while also acting to as shock absorbers for the stethoscope head 30. The stethoscope head 30 is connected via circuits to the switch 100 and the transmitter 120. When the switch 100 is pressed, the microphone 260 is activated. The outside of the housing provides a nonslip grip. A small ring 150 enables to attach the device via a wrist or neck strap (not illustrated in the patent figure) to prevent accidental drop damage.

A cordless stethoscope for use in hazardous material environments comprising a fluid tight hand held sound sensing device having a stethoscope head for sensing auscultatory sounds, a transmitter for transmitting sounds sensed by the device, a receiver for receiving transmissions from the transmitter and an ear piece for converting the received transmissions into audible sound. The housing is sized and shaped for being grasped by a gloved hand and is fluid tight for decontamination purposes. The sound sensing device may further comprise a microphone for sensing otherwise inaudible voice communications from a patient. The transmitter and receiver preferably uses magnetic induction transmissions to transmit sounds through barriers such as hazardous material suits that may be worn by clinicians during treatment of patients in possible hazardous material situations. [Abstract US7182733B2]