ITMI20120154A1 - SPINAL ANESTHESIA DEVICE - Google Patents

Description

DESCRIPTION

Of the Patent Application for Industrial Invention entitled:

â € œDevice for spinal anesthesiaâ €

FIELD OF APPLICATION

The present invention relates to a device for performing spinal anesthesia in a human or animal.

TECHNIQUE NOTE

As is known, spinal anesthesia involves inserting a needle through the vertebrae of a human (or animal) until it reaches the subarachnoid space where the anesthetic is injected.

The known technique provides for the use of a device comprising a spinal needle, an introducer needle, a mandrel and a handle. The introducer needle has a larger section than the spinal needle section, is more robust and is used to pierce at least the patient's skin. The introducer needle slides like a sleeve on the spinal needle. In turn, the spinal needle is connected to the handle. Finally, the stylet is configured with a thin thread that is inserted into the lumen of the spinal needle and closes it in order to prevent it from becoming clogged during insertion into the skin, the yellow ligament or the perdural space.

The doctor performing the anesthesia pushes the introducer needle through the skin and yellow ligaments of a patient's back (which are the hardest parts). Then, grasping the handle, he inserts the spinal needle into the epidural space to reach the dura mater. Finally, the doctor removes the stylet.

To be sure he is beyond the dura, the physician must wait for the cerebral fluid to drain through the needle and reach the handle. Conveniently, the handle is transparent and this allows the doctor to notice the arrival of the liquor.

This phase is the most delicate and critical of the procedure because the doctor, by letting the liquor flow through the needle, puts the central nervous system in communication with the outside world.

An error in this phase could have serious consequences for the patient. For example, an incorrect aseptic practice can involve serious risks of bacterial or viral contamination of the cerebral liquor with serious risks for the patient.

Once the doctor sees the liquor in the clear handle, the doctor connects a syringe to infuse the anesthetic.

The technical problem of the present invention is therefore to provide a device for spinal anesthesia which can operate in conditions of maximum safety for the patient and in particular which avoids putting the patient's central nervous system in communication with an external environment.

SUMMARY OF THE INVENTION

According to one aspect, the invention provides a spinal anesthetic device comprising a spinal needle, and a handle comprising a conduit in communication with said spinal needle and terminating at a hole configured to receive an anesthetic, in which said handle also includes: a one-way valve which, in its closed configuration, prevents a patient's fluid from escaping from the hole, and a fluid locking member configured to let the air contained in the spinal needle and duct escape and to block the escape of fluid through it, so that said fluid can fill the duct of the handle without escaping from it.

The handle can comprise a first portion connected to said spinal needle; a second distal portion with respect to said spinal needle; and a third central portion between the first portion and the second portion.

Preferably, the fluid locking member comprises a filter. The filter could be a hydrophobic filter.

In embodiments, the filter is disposed in the third portion of the handle.

In embodiments, a plug is coupled to the hydrophobic filter.

In embodiments, the filter also comprises a hydrophilic filter. The hydrophilic filter is coupled to said hydrophobic filter.

In embodiments the filter may comprise a hydrophilic filter.

The hydrophilic filter is preferably arranged in the second portion of the handle.

In embodiments, the filter is a substantially cylindrical member and is arranged around said one-way valve so as to put the duct in air communication with the outside.

The filter comprises a material that blocks the passage of air when in contact with a fluid. Preferably, the filter comprises a material such as porex or a similar material.

In embodiments, the device comprises an adapter with a truncated needle suitable for opening said one-way valve and with a neck suitable for receiving a portion of a syringe.

With the device for spinal anesthesia of the invention, the spinal anesthesia intervention is carried out in maximum safety, avoiding the contact of the CSF with the outside. Advantageously, in some embodiments of the invention, the intervention procedure of the known art is completely preserved. In other embodiments, the known intervention procedure is however largely maintained.

The invention will be described in detail in the remainder of the present description. Some embodiments will be illustrated, given only by way of non-limiting example, with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figs. 1a and 1b show a first embodiment of a spinal anesthesia device according to the present invention;

Figs. 2a and 2c show a second embodiment of a spinal anesthesia device according to the present invention;

Figs. 3a and 3b show a third embodiment of a spinal anesthesia device according to the present invention; And

Figs. 4a, 4b, 4c and 5 show a fourth embodiment of a spinal anesthesia device according to the present invention.

DETAILED DESCRIPTION

A device 1 for spinal anesthesia according to the invention comprises a spinal needle 2 and a handle 10, associated with the spinal needle 2. The spinal needle 2 is substantially in the shape of a hollow cylinder and is therefore configured to allow a passage of fluid from a patient to the handle 10 and / or in the opposite direction. The handle is in a distal position to the patient and is opposite the pointed end of the needle. The handle includes a conduit that prolongs the passage of fluid in the needle. According to the invention, the device 1 comprises a filter 11, 21, 31, 41 which lets the air contained in the main needle 2 escape without letting the liquor flow out. Advantageously, the liquor is blocked in the handle 10. In this way a closed system is created which prevents communication between the central nervous system and the external environment.

In the various figures, for greater clarity, the introducer needle is not shown.

With reference to the figures, the device 1 for spinal anesthesia according to the invention comprises a spinal needle 2, a handle 10, associated with the spinal needle 2, and a mandrel 18 (shown only in Fig.4a).

The handle 10 comprises a first portion 13 proximal to the spinal needle 2. This first portion 13 is configured to support the spinal needle exiting the handle 10.

The handle 10 further comprises a second portion 14 distal to the spinal needle 2. This second portion has an axial hole 141 for receiving an anesthetic fluid from a syringe 20 or the like.

The handle 10 also comprises a third central portion 15 interposed between the first portion 13 and the second portion 14. This third central portion 15 is preferably of a reduced diameter so that the doctor can easily grasp the handle 10 between two fingers of one hand.

The handle 10 has a central duct 16 which runs along its longitudinal axis. Figures 1a, 2a, 3a, 4a show, with a solid line arrow, a first flow direction 161 from the tip of the spinal needle towards the handle 10. It is also shown, with a discontinuous line arrow, a second flow direction 162 from the handle 10 to the tip of the needle. The liquor flows in the first direction 161 while the anesthetic (possibly mixed with liquor) flows in the second direction 162. Preferably, the handle 10 is substantially at least partially transparent to allow the visibility of the fluid flowing in the central duct 16.

According to the invention, the handle 10 also comprises a one-way valve 17, 47 to prevent a passage of fluid from the inside of the handle 10 towards the external environment, in the first direction 161. Preferably, the valve unidirectional 17, 47 is arranged in the central duct 16, near the hole 141.

The mandrel 18 (shown only in figure 4a, but present in all the embodiments of the invention) comprises a thin thread 181 which is inserted into the lumen of the spinal needle 2 and closes it in order to prevent it from becoming blocked during insertion into the skin, yellow ligament or perdural space.

The one-way valve 17, 47 is a non-return valve. In particular in the absence of the thread 181, when the mandrel 18 is withdrawn, the one-way valve 17, 47 avoids the backflow of fluid towards the outside of the device 1 in the first direction 161.

Preferably, the one-way valve 17, 47 has the shape of a duck bill.

The one-way valve 17, 47 comprises a first portion 171, 471 of substantially cylindrical shape positioned at the end of the handle 10 which is coupled with the mandrel 18.

The one-way valve 17, 47 comprises a second portion 172, 472 of substantially frusto-conical shape which acts as a guide towards the inside of the handle 10 in the second direction 162.

The spinal anesthesia device 1 will now be described according to different embodiments comprising the characteristics already described and further additional peculiar characteristics.

First embodiment of the invention With reference to Figures 1a and 1b, the device 1 for spinal anesthesia comprises a first filter 11 configured to let the air contained in the spinal needle 2 and in the duct 16 escape. According to the invention, the device 1 also comprises a plug 12, coupled to the first filter 11 configured to block the escape of fluid through it. By means of the first filter 11 and the cap 12, the fluid can fill the duct 16 of the handle 10 without escaping from the filter itself.

According to the invention, the first filter 11 comprises a hydrophobic filter.

Preferably, the filter 11 is arranged in the third portion 15 of the handle 10.

Operation of the device 1 in the first embodiment The physician performing the anesthesia pushes the introducer needle through the skin and yellow ligaments of a patient's back. Then, grasping the handle 10, he inserts the spinal needle 2 into the epidural space to reach the dura mater. Finally, when the doctor realizes that he has reached the dura, the doctor removes the mandrel 18 to free the lumen of the needle.

To be sure that he has reached the dura mater, the doctor waits for the cerebral fluid to drain through needle 2 in the first direction 161 and arrive at handle 10.

The air present in the duct 16, pushed by the liquor in the first direction 161, moves back up to the handle 10 to escape from the first filter 11. Since the filter is hydrophobic, the air comes out, but the liquor remains in the Inside of the handle 10 thus ensuring that there is no contact between the central nervous system and the external one.

Having emptied the air duct 16, the doctor attaches the syringe 20 to the handle 10 to infuse the anesthetic into the patient. The attachment of the syringe 20 causes a passage of air from the handle 10 towards the outside in the first direction 161. Consequently, a depression is generated in the handle 10 which could draw air from the outside towards the inside in the second direction 162, through the first filter 11. To avoid any kind of contamination of the liquor inside the handle 10 with air, in this situation the doctor closes the cap 12 after inserting the syringe 20.

In this way it is guaranteed that there is no suction of air towards the inside of the handle in the second direction 162. The doctor then proceeds with the infusion of the anesthetic in the first direction 161, via syringe 20.

Second embodiment of the invention With reference to figures 2a and 2b, the device 1 for spinal anesthesia comprises a second filter 21 configured to let the air contained in the spinal needle 2 and in the duct 16 escape and to block the fluid leaking through it; with this second filter 21 the fluid can fill the duct 16 of the handle 10 without escaping from the filter itself.

According to the invention, the second filter 21 comprises a hydrophobic filter 21a.

According to the invention, the device 1 also comprises a hydrophilic filter 21b coupled to the hydrophobic filter 21a.

In other words, the second filter 21 comprises a double membrane composed of a first hydrophobic layer 21a, which does not allow the passage of the liquor towards the outside, and a second hydrophilic layer 21b which does not allow the passage of air from the outside. towards the inside of the handle 10. In other words, the hydrophilic filter 21b performs the function of the cap 12 of the first embodiment, but does not require an actuation by the physician during the intervention.

Preferably, the filter 21 is arranged in the third portion 15 of the handle.

Operation of the device 1 in the second embodiment The physician performing the anesthesia pushes the introducer needle through the skin and yellow ligaments of a patient's back. Then, grasping the handle 10, he inserts the spinal needle 2 into the epidural space to reach the dura mater. Finally, the doctor removes the mandrel 18.

To be sure he is beyond the dura mater, the doctor waits for the cerebral fluid to drain through needle 2 in the first direction 161 and arrive at handle 10.

The air present in the duct 16, pushed by the liquor in the first direction 161, withdraws to the handle 10 to escape from the second filter 21. Since the filter is hydrophobic, the air comes out, but the liquor remains in the Inside of the handle 10 thus ensuring that there is no contact between the central nervous system and the external one.

The membrane is configured to allow the fluid to push the air outwards starting from the hydrophobic layer 21a (in contact with the inside) to transit towards the hydrophilic layer 21b (in contact with the outside ) and exit; when the membrane gets wet, that is, once the membrane is soaked with liquor, air is prevented from entering through the second filter 21.

When the doctor inserts the syringe 20, the air that could flow from the outside of the hydrophilic filter 21b in the second direction 162 does not have the strength to empty the soaked membrane and, therefore, cannot enter the handle 10.

In other words, the membrane reaches the bubble point, ie the condition in which the necessary force required to empty the second filter 21 is such as to prevent air from entering the filter itself.

Third embodiment of the invention With reference to Figures 3a and 3b, the device 1 for spinal anesthesia comprises the third filter 31 configured to let the air contained in the spinal needle 2 and in the duct 16 escape and to block the fluid leaking through it; with this third filter 31 the fluid can fill the duct 16 of the handle 10 without escaping from the filter itself.

The third filter 31 comprises a hydrophobic filter.

Filter 31 comprises a hydrophilic filter.

The hydrophilic filter is arranged in the second portion 14 of the handle. According to the invention, the third filter 31 is included in the second portion 14.

The second portion 14 is also defined with the term â € œluer lockâ €.

Compared to the first filter 11 and second filter 21, the third filter 31 is in a position even further back with respect to the main needle 2 in order to maximize the quantity of air coming out of the handle 10.

In other words, the third filter 31 is mounted in a portion of the device 1 proximal to the non-return valve 17.

For the infusion of the anesthetic in the second direction 162, the syringe 20 is equipped with a conical coupling 200 configured to engage in the second portion 14 up to the proximity of the third filter 31

Operation of the device 1 in the third embodiment The physician performing the anesthesia pushes the introducer needle through the skin and yellow ligaments of a patient's back. Then, grasping the handle 10, he inserts the spinal needle 2 into the epidural space to reach the dura mater. Finally, the doctor removes the mandrel 18.

To be sure he is beyond the dura mater, the doctor waits for the cerebral fluid to drain through needle 2 in the first direction 161 and arrive at handle 10.

The air present in the duct 16, pushed by the liquor in the first direction 161, moves back up to the handle 10 to escape from the first filter 11. Since the filter is hydrophobic, the air comes out, but the liquor remains in the Inside of the handle 10 thus ensuring that there is no contact between the central nervous system and the external one.

Once the air has been emptied from the duct 16, the doctor mounts the tip 200 on the end of the syringe 20 configured for the release of the fluid. Then it acts on the plunger of the syringe for the infusion of the anesthetic in the second direction 162.

Upon insertion of the conical coupling 200 in the handle 10, in particular in the second portion 14, the conical coupling 200 blocks the passage of air through the third filter 31, both inlet and outlet.

In other words, the third hydrophobic filter 31 functions as in the other embodiments described above, allowing the air to escape pushed by the fluid, but making the presence of the plug 12 of the first embodiment or of the filter 21b superfluous. of the second embodiment.

In fact, when the doctor inserts the syringe 20 into the handle 10, the conical coupling 200 occludes the third filter 31 blocking the passage of air. The advantage is, therefore, that in this embodiment, the doctor is not obliged to close the cap to prevent the entry of air from the outside when inserting the syringe.

Furthermore, a pair of hydrophobic / hydrophilic filters is not necessary to achieve the isolation of the central nervous system from the outside.

Fourth embodiment of the invention With reference to figures 4a, 4b, 4c and 5. the device 1 for spinal anesthesia comprises the fourth filter 41 configured to let the air contained in the spinal needle 2 and in the duct 16 escape. and to block the escape of fluid therethrough; with this fourth filter 41 the fluid can fill the duct 16 of the handle 10 without escaping from the filter itself.

The fourth filter 41 is a substantially cylindrical member and is arranged around the one-way valve 47 so as to put the duct 16 in air communication with the outside.

The fourth filter 41 comprises a material which blocks the passage of air when in contact with a fluid.

Preferably, the fourth filter 41 comprises a material such as porex or a similar material.

The device 1 further comprises an adapter with a truncated needle 19 suitable for opening the one-way valve 47 and with a neck suitable for receiving a portion of a syringe 20.

In other words, the truncated needle 19 acts as an adapter between the syringe 20 and the handle 10.

In other words, the device 1 comprises an adapter 19 configured to adapt an outlet of the syringe 20 to the one-way valve 47 to allow a connection of fluid towards the handle 10 in the second direction 162.

The fourth filter 41 is included in the third portion 15. Consequently, the one-way valve 47 is in a position in the handle 10 closer to the spinal needle than shown in the previous embodiments.

In this embodiment, the one-way valve 47 is of an absolute smaller size than the one-way valve 17 of the other embodiments because it is surrounded by the porous filter 41.

Preferably, the fourth filter 41 has a length of about 4mm; the one-way valve 47 is fixed inside.

Operation of Device 1 in the Fourth Embodiment The physician performing the anesthesia pushes the introducer needle through the skin and yellow ligaments of a patient's back. Then, grasping the handle 10, he inserts the spinal needle 2 into the epidural space to reach the dura mater. Finally, the doctor removes the mandrel 18.

To be sure he is beyond the dura, the doctor waits for the cerebral fluid to drain through needle 2 in the first direction 161 and arrive at handle 10.

The air present in the duct 16, pushed by the liquor in the first direction 161, moves back up to the handle 10 to escape from the fourth filter 41.

The fourth filter 41 is configured to allow air to escape and to expand when it comes into contact with a liquid, closing the passage of the liquid to the outside.

In fact, as soon as this filter comes into contact with the liquid (even without getting soaked) the material expands and the pores close. So the liquid no longer passes.

Given the particular arrangement and conformation of the fourth filter 41, the conventional syringe 20 is unable to open the one-way valve 47 to allow the infusion of the anesthetic.

With reference to figure 4a, the doctor removes the stylet to free the one-way valve 47 so that the liquor returns, in the first direction 161, towards the handle 10 and wets the membrane 41, locking itself in the handle 10.

With reference to figure 4b, the doctor uses a truncated needle 19 to enter the device 1.

With reference to figure 4c, the doctor, after having fitted the truncated needle 19 onto the syringe 20, infuses the anesthetic in the second direction 162, sinking the truncated needle into the valve 47, causing it to open.

Alternatively, the so-called “barbottagge” technique can be used; in other words, the doctor waits for the CSF reflux in the first direction 161, then injects the anesthetic into the handle 10, to mix the CSF with the anesthetic. After mixing, the doctor infuses the anesthetic in the second direction 162 towards the patient's back.

The described invention achieves the following advantages: the spinal anesthesia operation is carried out in maximum safety, avoiding contact of the liquor with the outside.

In some embodiments of the invention, the intervention procedure of the prior art is completely preserved.

In other embodiments, the known intervention procedure is however largely maintained.

Claims (14)

CLAIMS 1. Device (1) for spinal anesthesia comprising: â € ¢ a spinal needle (2), e â € ¢ a handle (10) comprising a duct (16) in communication with said spinal needle (2) and ending at a hole (141) configured to receive an anesthetic, wherein said handle (10) also comprises: â € ¢ a one-way valve (17, 47) which, in its closed configuration, prevents a patient's fluid from escaping from the hole (141), and â € ¢ a fluid blocking organ (11, 21, 31, 41) configured to let the air contained in the spinal needle (2) and the duct (16) escape and to block the escape of fluid through it, in such a way that said fluid can fill the duct (16) of the handle (10) without coming out of it. Device (1) according to claim 1, wherein said handle (10) comprises: â € ¢ a first portion (13) connected to said spinal needle (2); â € ¢ a second portion (14) distal to said spinal needle (2); and â € ¢ a third central portion (15) between the first portion (13) and the second portion (14). Device (1) according to claim 1 or 2, wherein said fluid locking member (11, 21, 31, 41) comprises a filter. Device (1) according to claim 3, wherein said filter (11, 21, 31, 41) comprises a hydrophobic filter. 5. Device (1) according to claim 4, wherein said filter (11, 21, 41) is arranged in said third portion (15) of the handle. Device (1) according to claim 4 or 5, also comprising a plug (12) coupled to said hydrophobic filter. Device (1) according to claim 4, wherein said filter (21) also comprises a hydrophilic filter (21b). Device (1) according to claim 7, wherein said hydrophilic filter (21b) is coupled to said hydrophobic filter (21a). Device (1) according to claim 3, wherein said filter (11, 21, 31, 41) comprises a hydrophilic filter. Device (1) according to claim 8, wherein said hydrophilic filter (21b) is arranged in said second portion (14) of the handle. 11. Device (1) according to any one of claims 1-3, wherein said filter is a substantially cylindrical member and is arranged around said one-way valve (17, 47) so as to put the duct (16) with the outside. Device (1) according to claim 11, wherein said filter comprises a material which blocks the passage of air when in contact with a fluid. Device (1) according to claim 12, wherein said filter comprises a material such as porex or a similar material. Device (1) according to claim 11, 12 or 13, wherein said device comprises an adapter with a truncated needle suitable for opening said one-way valve (17, 47) and with a neck suitable for receiving a portion of a syringe.