Suction devices

Abstract: A suction device (10) is disclosed comprising a moulded plastics handle (12) having a suction bore (14) therethrough and the spiggot (16) for connection between the hospital suction source. The device further comprises a probe (18) having a suction passage (20) therethrough and terminating in a suction tip (22). At its proximal end the probe (18) is formed with a male thread (48) which threadedly engages in internal threads (34) provided at an enlarged entrance portion (30) of the handle (12). The proximal end of the probe (18) terminates in an end member (52) which fits within a reception bore (26) located between the front bore and the suction bore (14) of the handle (12). The dimensions of the end member (52) are such that there is an annular space (54) between the reception bore (26) and the end member (52) and this space (54) connects through an opening (58) through the suction bore (14). The handle (12) has a controllable suction port (38) whereby the suction at the tip (22) can be controlled. This port (38) opens into the annular space (54) upstream of the connection between the opening (58) and the suction bore (14). Various modifications including modifications for use with flexible catheters are also described.

Description: This invention relates to suction devices and in particular such devices for medical, surgical or dental use. BACKGROUND TO THE INVENTION. Suction devices are used for medical, surgical or dental use to remove foreign matter, fluid, blood, pus, mucous, polyps, bone particles, necrotic and cancerous matter and the like (all of which are hereinafter referred to as "waste matter"). Such suction devices are normally provided in two types viz a suction nozzle comprising a rigid nozzle or a suction catheter comprising an elongated flexible catheter which can be inserted into the body as desired. The nozzle or catheter is normally connected to a suction source via an intermediate member which is connected by connection means to a flexible tube that is connected to the suction source, the connection means being normally in the form of a hollow spigot. In the suction nozzle the intermediate member may comprise a handle that may be integral with the probe. In order that the suction can be controlled, a suction port may be provided in the intermediate member leading to the suction passage therethrough and the medical personnel operating the suction device, by obturating the suction port to a greater or lesser extent, can vary the suction at the tip of the probe. US-A-3 828 780 discloses a combined electro-coagulator-suction instrument useful for coagulation bleeding capillaries and veins within a surgical field for sucking out blood and other liquids from the field. It discloses a body formed as a monolithic complex moulding with an obturatable port leading to a suction body. This makes for difficult and comparatively expensive moulding and would additionally probably necessitate a branch line of relatively large cross section being formed. According to one aspect of the invention there is provided a suction device comprising a suction member having an internal suction passage terminating at a suction tip at the distal end thereof; and an intermediate member having a connection part for connection to a source of suction, a suction bore that is connectable to the suction passage of the suction member, to form a suction line through the device, and a finger controllable suction port; there being a conduit which is parallel to the suction line and its cross-sectional dimension that is perpendicular to its axis is narrow in size and which connects the suction port to the suction line characterised in that the member is separate from the intermediate member and has an end part entering the suction bore of the intermediate member and defining therewith the conduit. The conduit may have its other dimensions being quite large so that its flow area is adequate to permit sufficient air flow therethrough when the suction port is open so that there will be no or very little suction at the tip of the suction member. The conduit preferably connects to the suction passage downstream of its connection to the suction port i.e. when the suction port is open, there will be air movement in the conduit in the same direction as the movement in the suction passage through the intermediate member. The end part is preferably a tubular end member that is received in coaxial spaced relationship in the suction bore so as to form an annular conduit between the end part and the bore. The suction member is preferably separate from the intermediate member and preferably has a hollow spigot that fits within a reception bore in the intermediate member in such a way that the conduit is formed between the spigot and the bore, the conduit preferably being of annular cross-section. The reception bore may form part of the suction passage through the intermediate member. However the reception bore is conveniently of larger diameter than the suction passage, there being connection opening means between the conduit and the suction passage which opening means also has one dimension that is very small. The suction member may comprise a flexible catheter connected to the intermediate member in which case a union is preferably provided on the catheter connecting it to the intermediate member. The suction member and the intermediate member are preferably capable of being separated from one another and conveniently the intermediate member has a forward opening provided with internal screw threads and the suction member has a part formed with external screw threads engage the internal screw threads. Preferably engaging means are provided on the suction and intermediate members which limit the relative members to rotation thereof. In modifications of the invention, the free end of the cylindrical end member may be cut off at an incline to the axis thereof. Alternatively the end part may comprise a shield that butts against the suction bore to define therewith the conduit. In a further alternative arrangement, the end of the suction member closer to the intermediate member may have a thickened wall and the controllable suction port is formed in such wall. The conduit in this arrangement may includes a plenum chamber also formed in said thickened wall. The nozzle and the handle preferably comprise different materials. Embodiments of the invention will now be described by way of example with reference to the accompanying drawings. In the drawings: Figure 1 is a plan of a controllable suction nozzle of the invention, Figure 2 is a section on line 2 - 2 of Figure 1, Figure 3 is an enlarged detail of Figure 2, Figure 4 is a view similar to Figure 3 showing the parts in the exploded condition, Figures 5, 6, 7 and 8 are respectively views similar to Figure 3 of modified suction nozzles of the invention, Figure 9 is a section on line 9 - 9 of Figure 8, and Figure 10 is a view similar to Figure 3 of a suction catheter of the invention. DESCRIPTION OF THE CURRENTLY PREFERRED EMBODIMENT OF THE INVENTION Referring now to Figures 1 to 4, there is shown a controllable suction nozzle 10 of the invention. The nozzle 10 comprises a hollow handle 12 having a suction bore 14 running along its length. At its rear end, the handle 12 has an integral spigot 16 formed thereon through which the suction bore 14 passes. This spigot 16 is generally frusto-conical in shape so as to be able to be received within a flexible suction tube (indicated in chain lines at 17) connected to a hospital's suction apparatus. At its front end, the handle 12 is connected to a hollow elongated rigid probe 18 having a suction passage 20 therethrough. At its forward or distal end, the probe 18 ends in a tip 22 with suitable suction openings 24 leading into the passage 20. The handle 12 comprises an injection moulded ABS (acrilonitrile-butadiene-styrene) member containing colouring matter to make it opaque. The probe 18 is an injection moulded, substantially transparent acrylic member. The precise materials to be used will be apparant to any moulder skilled in the art. I have found that these parts engage and disengage easily and smoothly. The front end of the handle 12 has an enlarged reception bore 26 (best shown in Figures 4 and 5) that is coaxial with the suction bore 14 and has a base 28 lying in a plane radial to the axis 26 a of the reception bore. The diameter of the bore 26 is 10mm. The bore 26 leads to an enlarged entrance section 30 to which it is connected by a frusto-conical part 32. The entrance section 30 has internal square section threads 34 formed therein. Above the bore 26 there is a shallow finger depression 36 formed in the outer surface of the handle. A four millimetre diameter port 38 at the end of a radial passage 39 is provided at the lowest portion of the finger depression. Finger grip depressions 40 are provided on either side of depression 36. The proximal or rear end of the probe 18 is provided with a spigot 42, there being a radial shoulder 44 between the probe 18 and the spigot. The spigot 42 has a short externally threaded cylindrical portion 46 which has a square section thread 48 formed thereon to fit threadedly into the threads 34 in the reception bore 26. The thread 48 extends through 540° (five hundred and forty degrees). The spigot 42 has a frusto-conical section 50 beyond the threaded portion 48 which is complementary to the portion 32 of the bore 26 and lies flush thereagainst to limit the inward movement of the spigot 42 into the bore 26 and also to seal thereagainst. The end of the section 50 is stepped down to a cylindrical end portion 52 of reduced external diameter which is two millimetres smaller than the diameter of the bore 26. The end portion 52 lies in spaced co-axial relationship within the reception bore 26 so that there is an annular space or conduit 54 between the end 50 and the bore 26. The end face 56 of the spigot 42 is located about one millimetre short of the shoulder 28 between the reception bore 26 and the suction bore 14 and closer to the rear end of the bore 14. Thus there is a cylindrical opening 58 between the annular space 54 and the bore 14 and the port 38 is in pneumatic contact with the suction bore 14 through the annular space 54 and the opening 58. It will be noted that this latter opening 58 is downstream of the join of the radial bore 39 and the annular space 54. It will further be noted that the cross-sectional area of the annular space 54 is quite substantial but that the narrowest dimension of the space, i.e. its radial width is small. In this embodiment the cross-sectional area of the annular space 54 is 28,28mm² and the radial width is one millimetre. Similarly the cross-sectional area of the opening 58 (which is cylindrical in shape) is also substantial (29,13mm²) while the narrowest dimension, i.e. the axial length of the opening (1mm), is small. The axis of the port 38 joins the annular space 54 five millimetres behind the end face 56 of the spigot 42. The probe 18 is inserted into the handle 12 by placing the spigot 42 into the bore 26 with the probe 18 located at a position 180° from its normal working position. The threads 48 engage in the female threads 34 and the probe 18 is rotated through 540° (i.e. one and a half turns) until it reaches its desired operating position. Further movement of the spigot is prevented by engagement of the frusto-conical surfaces 50 and 32 and by the shoulder 44 of the probe 18 butting against the front end 12 a of the handle. When suction is applied to the suction nozzle, air is drawn into suction passage 14 both from the nozzle tip and the suction port 38. When the suction port 38 is open there will be little or no suction at the nozzle tip. As the suction port 38 is obturated to a greater degree by the anaesthetist's finger, the suction at the tip will be increased and of course when the suction port 38 is wholly obturated, the full suction will be applied at the nozzle tip. The controllable suction nozzle 10 can be manipulated in conventional manner by an anaesthetist into the mouth or pharynx of a patient so that the suction can be applied to matter to be removed therefrom. It can also be used to suck body fluids from the abdomen or other body cavity of a patient who is being operated upon. Because the suction can be controlled by the anaesthetist as described above, the chance of damage to tissue underlying the waste material being caused by the suction can be minimised or totally avoided. It will be noted that the direction of air movement changes at right angles from the suction port 38 to along the conduit 54, then at right angles through the opening 58 and then again at right angles into the suction bore 14. I have found that the suction nozzle 10 operates effectively and well. Furthermore because the connection between the annular conduit 54 to the passage 14 is upstream of opening 56, waste material will not migrate to the port 38. I believe that because of the enlargement of the flow passage at the opening 58, increased suction will be caused - through the conduit 54. This will provide inter alia improved clearing of conduit 54 when the nozzle is connected to suction and the suction port 38 is at least partially open. I believe that the annular conduit 54 also serves as a plenum chamber which also serves to prevent movement of the waste material to the suction port 38. Indeed the air flow through the conduit 58 will move such matter away from the suction port 38 which will normally if not always remain clean in use. Thus the medical personnel's finger will not be contaminated by such waste matter. I have also found that when the nozzle 10 is hung up as some times occurs in the theatre or recovery room, waste matter in the nozzle which will tend to move down the suction bore 14 will not pass through the gap 58 but will instead take the path of least resistance and pass down the passage 20. The possibility of the waste matter entering the annular conduit 54 which is extremely small or minimal is reduced still further in the Figure 5 embodiment to be described below. Furthermore, because the suction nozzle 10 is formed in two parts, the mould in which the parts are made can be of significantly less size, as can be the mould insert(s), and consequently is less costly than the moulds for conventional suction nozzles. These nozzles 10 thus can be disposable. In addition, the probes can be of varying shapes and sizes and tip configurations can be mounted on a handle of one shape, thus reducing still further the costs of manufacture while permitting the anaesthetist considerable scope in the choice of probe to be used. I have further found surprisingly that the suction noise of the nozzle 10 is much lower than that of conventional suction nozzles. This noise can barely be heard against the noises in the operating theatre and does not cause irritation and distraction in the operating theatre. It is thought that the end member 50 on the spigot 42 serves as a baffle which reduces noise as aforesaid. DESCRIPTION OF SOME MODIFIED SUCTION NOZZLES OF THE INVENTION The modified nozzle shown in Figure 5 is generally similar to the embodiment of Figures 1 to 4 (and wherein the reference numbers for identical parts are the same with the addition of 100 to the numbers) save that the end 156 of the spigot 142 is provided with castellations 160 which engage the base 128 of the reception bore 126. Thus the opening 158 is formed by a plurality of ports 162 between the castellations 160. Reference is now made to Figure 6. The nozzle 170 therein shown is substantially identical to the nozzle 10 save that the end member 172 has its front face 176 cut on an incline. The passage 178 from the suction port 180 enters the reception bore 182 upstream of the end of the longest portion of the end member which is located directly below the suction port 180 i.e. it enters into a narrow conduit 184 prior to being connected to the reception bore. In the embodiment of Figure 7, the nozzle 186 has a reception bore 188 is of the same diameter as, and is a continuation of, the suction passage. Thus the annular conduit 190 surrounding the end part 192 of the spigot enters into the suction passage through an annular opening without a further change of direction of the air passing therethrough. The suction nozzle 110 b illustrated in Figures 8 and 9 is generally similar to the suction nozzle 10 save that the spigot does not have an annular end 50. Instead the spigot 142 b is provided with a chordal shield 151 b that seals against the walls of the reception bore 126 b (as best shown in Figure 9) to leave an elongated passage 154 b whose radial dimension is small. This passage 154 b connects with the suction port 114 b through a narrow opening 158 b that is located downstream of the suction port 138 b . The suction nozzle 110 b operates in the same manner as the embodiments described above. The provision of the small conduit 154 b prevents waste matter migrating to the suction port 138 b and contaminating the aneasthetist's finger. DESCRIPTION OF A MODIFIED SUCTION CATHETER OF THE INVENTION Referring now to Figure 10, there is shown a detail of a suction catheter device 210 of the invention. The device 210 comprises a flexible catheter 212 that extends any desired length and terminates in a suction tip (not shown) at its distal end. A connector or union 214 is attached to the proximal end of the catheter. The union 214 includes a front spigot 216, a flange 218 leading to a cylindrical body 220 having a frustoconical section 222 that terminates in a smaller end spigot 224. Male threads 226 are provided on the body 220. A suction passage 228 connected to the bore 230 of the catheter 212 extends through the union 214. The union 212 fits into the front end of an intermediate member 232 which has an entrance bore 234 provided with internal threads 235 and leading via a frusto-conical part 236 to a reception bore 238. The reception bore 238 has a flat base 240 into which opens a suction passage 242 of smaller dimensions. The intermediate member 232 terminates in a spigot 244 which fits into the theatre suction pipe 246. A radial boss 248 extends from the central portion of the intermediate member 232 and has at its upper end a finger rest 250. A suction port 252 is provided in the finger rest leading to a short bore 254 that extends radially of and into the reception bore 238. As mentioned above, the union 214 fits the front end of the intermediate member. The body 220 fits the entrance bore 234 with the male threads 226 engaging the internal threads 235. The frusto-conical section 222 butts and seals against the frusto-conical part 236 of the bore and the end spigot 224 is co-axially received within the reception bore 238 in such a way that there is an annular conduit 256 therebetween. The end face 258 of the end spigot 224 is spaced slightly from the base 240 of the reception bore 238. Thus there is a cylindrical opening 260 between the conduit 256 and the suction passage 242. The bore 254 enters the conduit 256 upstream of the opening 260. GENERAL All the embodiments described are inexpensive and can be disposable. No moving parts are required for the operation and control of the suction device. Because of the controlled amount of rotation of the probe as described above (viz one and a half turns) and the disposition of the threads, the precise and repeatable angular positioning of the probe relative to the handle in the suction nozzles above described can be effected. The invention is not limited to the precise constructional details hereinbefore described and illustrated. For example, the handle may be of any desired shape and size and the probe can be of any desired shape and size. The tip of the probe can be shaped or configured as desired. The connection between the probe and the handle can be varied as desired and indeed the probe can be permanently secured to the handle. Some or all of the finger depressions may be differently shaped or could be omitted. The probe and or the handle may comprise different materials with the probe being preferably transparent. Although the materials are preferably plastics materials, one or both of the parts can comprise metal. The arrangement with a catheter need not incorporate the boss and finger plate, the suction port being formed directly in the intermediate member. The nozzle may of course be used by medical personnel not only in the operating theatre but also in the recovery room or wheresoever medical draining or suction is required. The various dimensions given apply to the currently apparatus of the invention. However these dimensions may vary as required save that the narrow dimension of the conduit (54 etc) should be sufficient for the waste member to form a miniscus thereacross i.e. normally up to about 3 mm and preferably about 1 mm. The suctions devices can be put to other uses with or without such suitable modification for such purposes. Thus they may be used for sucking, removing or transfering matter in a controlled manner in industrial or laboratory conditions without the operator having his finger contaminated thereby.

Claims: A suction device comprising a suction member (18) having an internal suction passage (20) terminating at a suction tip (24) at the distal end thereof; and an intermediate member (12) having a connection part (16) for connection to a source of suction, a suction bore (14) that is connectable to the suction passage (20) of the suction member, to form a suction line (20, 14) through the device, and a finger controllable suction port (38); there being a conduit (54) which is parallel to the suction line (20, 14) and its cross-sectional dimension that is perpendicular to its axis is narrow in size and which connects the suction port (38) to the suction line (20, 14), characterised in that the suction member (18) is separate from the intermediate member and has an end part (50) adapted to enter the suction bore (14) of the intermediate member (12) and defining therewith the conduit (54, 58). A device as claimed in claim 1 characterised in that the end part (50) is a cylindrical part that is received in coaxial spaced relationship in the suction bore (14) forming an annular conduit (54) between the end part (50) and the suction bore (14). A device as claimed in claim 1 or claim 2 characterised in that the suction bore (14) has an enlargement (26) at its distal end forming a reception bore in which the end part (50) is received. A device as claimed in claim 3 in which there is a surface (28) at the junction between the reception bore (26) and the remainder of the suction bore (14) characterised in that the proximal end (56) of the said member (50) terminates short of this surface (28) and in that an opening (58) is formed between the surface (28) and the end (56) of the end member (50) through which the conduit communicates with the suction bore. A device as claimed in any one of the preceding claims characterised in that the intermediate member (12, 232) has a forward opening (30, 323) provided with internal screw threads (34, 235) and the suction member (18, 212) has a part (42, 214) formed with external screw threads (48, 226) that engage the internal screw threads. A device as claimed in any one of the preceding claims characterised in that the suction port (38) is connected to the conduit (54) upstream of its connection with the suction bore (14). A suction device as claimed in any one of the preceding claims characterised in that the suction member comprises a flexible catheter (212) having a connector (214) at one end to constitute the said end part. A device as claimed in any one of the preceding claims characterised in that the narrow dimension of the conduit is one millimetre. A device as claimed in any one of the preceding claims characterised in by a finger rest (250) raised from said intermediate member (232), the suction bore (254) extending through the finger rest.

Inventors: NATES COLIN DR, NATES, COLIN, DR.
Applicants: NATES COLIN DR, NATES, COLIN, DR.
Application year: 1991
Main classification: A61M1
IPC codes: A61C17, A61M1