WO1997005591A1

WO1997005591A1 - Manikin for simulating cardiac pathologies

Info

Publication number: WO1997005591A1
Application number: PCT/EP1996/003131
Authority: WO
Inventors: Alberto Rovetta; Massimo Pagani; Livio Dei Cas; Marco Pedevilla; Stefano Martinini
Original assignee: Pharmacia and Upjohn SpA
Current assignee: Pfizer Italia SRL
Priority date: 1995-07-26
Filing date: 1996-07-17
Publication date: 1997-02-13
Anticipated expiration: 1998-01-26
Also published as: ITMI951630A0; ITMI951630A1; AU6700296A; IT1277357B1

Abstract

The manikin comprises a profile shell (1) covered by an elastic membrane (2) and housing at least one electromechanical transducer (M, L) arranged to transmit pulsations of variable frequency and variable amplitude to a defined area of said membrane (2), the transducer being of the type comprising a fixed permanent magnet (4, 5) and a movable coil (6) positioned and movable between the pole pieces of the magnet and traversed by current fed by a computerized system.

Description

MANIKIN FOR SIMULATING CARDIAC PATHOLOGIES

The invention relates to a manikin able to simulate cardiac pathologies and usable for the training of cardiologists.

In training students and cardiologists, the ideal would be to have available persons with the most varied cardiac pathologies to be able to observe the different specific symptoms for each pathology. In practice this possibility does not exist, with the result that training is necessarily superficial or incomplete and in any event unsatisfactory.

To overcome these problems, manikins have been constructed incorporating some resemblance to the trunk, the arms and the head of an actual person. These manikins house sensors and transducers (ie devices which transform an electrical signal into mechanical movement) which, for the principal points of the manikin, enable sounds and movements characteristic of the most diverse and typical pathologies for these points to be generated. The sounds can be detected by a stethoscope, the movements being detected either by direct observation or by palpitation.

Manikins of this type are described in the patents US-A-3,662,076, US-A-3,888,020, US-A-3,947,974, US-A-4,601 ,665, US-A-4,828,501 , US-A-4,932,879, GB-A-2,193,029 and EP-A-0,561 ,658.

In addition to describing devices arranged to emit sounds detectable by a stethoscope and electromechanical transducers arranged to impart movements to well defined zones of the manikin's surface, these patents illustrate the most varied systems (controlled by recorders or computerized systems) for obtaining the desired sound emission or the required sequence of movements at the various points of each manikin, on the basis of the pathology to be simulated.

Limiting our attention to the system for transmitting movement to those zones of the manikin which are of interest, it will be noted that US-A-3,662,076 describes a series of cams driven continuously always in the same direction by a variable speed electric motor, these cams comprising pumps which transmit an oscillatory movement to pistons positioned below and in contact with an elastic membrane simulating the manikin's skin; US-A-4,601 ,665 describes a system in which the pistons positioned below and in contact with the manikin's "skin" consist of the rods of electromechanical transducers in wich the same rods form part of a permanent magnet or a ferromagnetic material able to traverse telescopically within the cavity of a solenoid through which an electric current fed by the control system for this device flows; and GB-A-2,193,029 describes a manikin construction in which different constituent parts of the chest of the manikin are mounted on pins on which they can be made to rock between two positions by electromagnetic attraction.

All the stated manikins can be easily controlled to transmit oscillations of fixed or variable frequency to the manikin's

"skin", but none of them enables the amplitude of the mechanical oscillation of the manikin's "skin" to be varied when required, and in a very simple manner, in correspondence with the zone in which the relative electromechanical transducer is positioned.

The main object of the present invention is to provide a manikin for cardiac pathology simulation, which is able to transmit to selected zones of the manikin's "skin" mechanical oscillations of frequency and especially amplitude variable between a minimum and a maximum compatible with the pathology to be simulated.

A further object is to provide a manikin of the aforesaid type which is of simple and economical construction and of reliable operation.

These and further objects are attained by a manikin comprising a profiled shell externally covered by an elastic membrane and internally housing at least one electromechanical transducer acting on a limited zone of said membrane to transmit pulsations thereto consequent on electrical pulses fed to said transducer by a computerized generator, characterised in that said electromechanical transducer is of the type comprising a fixed permanent magnet and a movable coil positioned and movable between the pole pieces of the magnet and traversed by current fed by a computerized control system.

Preferably said electromechanical transducer is a linear motor.

The structure and characteristics of the manikin according to the invention will be more apparent from the description of one embodiment thereof given hereinafter by way of non-limiting example with reference to the accompanying drawing, in which:

Figure 1 is a schematic view from above showing the manikin covered by the elastic membrane simulating a patient's "skin". Figure 2 is a schematic enlarged detail of one of the transducers housed within the manikin.

The manikin shown schematically in the drawings comprises a profiled shell (constructed for example of aluminium, sheet steel or polycarbonate) 1 simulating a human thorax and covered externally by an elastic membrane 2 (for example consisting of a rubber or silicone film) simulating the human skin.

Apertures are provided in the shell in correspondence with zones in which it is desired to observe movements typical of certain cardiac pathologies. For simplicity, one of these apertures is shown on the drawing, positioned in correspondence with the heart point, another examination point being provided in the neck of the manikin, in correspondence with a carotid artery.

Within the thoracic cavity bounded by the shell 1 there is housed a linear electric motor M comprising a movable rod 3 positioned between the pole pieces 4 of a permanent magnet. The movable rod 3, which is in contact with the elastic membrane 2, incorporates one or more electric coils powered by a computerized control system arranged to generate oscillations in said rod the frequency and amplitude of which depend on the electrical signal fed to the coil incorporated in the rod.

The linear electric motor is not described in greater detail because such motors are well known. One form thereof is described for example in US-A-4,998,420.

A linear motor is advantageously used in correspondence with the heart point of the manikin where it enables an ictus to be perfectly simulated.

Linear motors can also be used at further points of the manikin, whereas this is not possible at certain other points because of the limited available space.

For example in the manikin's neck, in correspondence with each carotid artery where it is desirable to detect the pulsation deriving from the heart beat, the electromechanical transducer L (see Figure 2) is totally similar to a common loudspeaker from which the flexible membrane has been partly removed. This transducer comprises a permanent magnet 5, between the pole pieces of which there is positioned a movable coil 6 with which there is rigid a dome 7 in contact with the membrane 2.

The coil 6 is powered by a computerized system (easily conceived by an expert of the art and in fact totally similar to that described in detail in the prior patents cited in the introduction to this description), which causes the coil 6 (and hence the dome 7 and the membrane 2 in contact with it) to move axially with oscillations of adjustable frequency and amplitude so as to exactly reproduce the movements which would occur in correspondence with the carotid artery of an actual patient suffering from the most diverse cardiac pathologies.

The enlarged detail of Figure 2 also shows a membrane portion 8 acting as an elastic spring to retain the coil 6 between the pole pieces of the permanent magnet.

Transducers similar to that indicated by the letter L can also be advantageously used in correspondence with other points on the manikin, for simplicity not shown on the drawing, for example in correspondence with the wrists, the brachial artery and the groin (radial) .

If the manikin comprises more than one electromechanical transducer, each is controlled independently of the others to reproduce the actual characteristics of the movements to be detected in a patient.

Claims

Claims :

1. A manikin for simulating cardiac pathologies, comprising a profiled shell externally covered by an elastic membrane and internally housing at least one electromechanical transducer acting on a limited zone of said membrane to transmit pulsations thereto consequent on electrical pulses fed to said transducer by a computerized generator, characterised in that said electromechanical transducer is of the type comprising a fixed permanent magnet and a movable coil positioned and movable between the pole pieces of the magnet and traversed by current fed by a computerized control system.

2. A manikin as claimed in claim 1, characterised in that said electromechanical transducer is a linear motor.