GB2216009A - Suprapublic flushing water drain - Google Patents

Description

I 1 2216009 -V SUPRAPUBIC FLUSHING WATER DRAIN The invention relates to a

suprapubic flushing water drain of the type including a shaft for the discharge from the bladder of flushing water supplied by a transurethrally positioned resection instrument.

When performing a transurethral resection, the endoscopic resection instrument is introduced into the bladder region through the urethra (urine duct) in order to perform the operation, generally by means of an electrically actuated cutting blade, typically a high frequency heated wire loop. The operation can be necessary at the bladder wall or, in the majority of cases, in the region of the prostate gland.

In order to provide a free field of view in front of the instrument even in the event of relatively severe bleeding, flushing water is supplied to the field of view through a supply channel provided in the instrument. In earlier methods the flushing water was intermittently discharged again through the same channel but in the continuous flushing method which is generally used nowadays it is discharged through a separate channel so that continuous flushing is possible.

In the method of Iglesias the channel and the discharge passage are provided in the transurethrally positioned instrument. In the method which is increasingly used nowadays, a special drain passage is provided in a suprapubic flushing water drain shaft.

For this purpose the bladder is firstly pierced from the exterior above the os pubis (pubic bone) with the aid of a trochar and the drain shaf t then placed into the pierced passage created. The drain shaft 2 constitutes essentially a tube open at both ends which acts as the flushing water outlet. Provided at its outer proximal end is a discharge hose.

As in all the flushing methods mentioned above, the flushing water pressure in the bladder must be monitored with great care in the suprapubic method also. If this pressure is too high water enters the blood circulation system through the blood vessels opened in the operation and leads to the known TUR (transurethral resection) syndrome with consequences which under certain circumstances can be serious for the patient. The pressure in the bladder must thus be maintained below a maximum permitted value of a f ew decimetres water but on the other hand a good flushing action with a water flow of about one litre per minute is important. Blockages in the drain passage if the supply pressure remains constant can rapidly cause an excessive increase in the bladder pressure.

A suprapubic f lushing water drain of the type referred to above is known from the German Publication "Uroldge W' ("Urology B") 1986 Volume 26, pages 189 to 192 (Fig. 3).

In addition to a central water drain passage this known drain affords in the shaft a second pressure measuring passage which connects the distal tip region with a proximal connection and to which a manometer may be proximally connected for pressure monitoring purposes. The pressure monitoring is thus facilitated but constant monitoring and flow adjustment is required in order to maintain the pressure below the critical value. There is alsothe disadvantage with this drain that due to the provision of two passages in the shaft the actual drain passage is relatively narrow and can b 3 easily become blocked. A further disadvantage is that if the suction at the outlet is too strong the bladder can be sucked dry. The bladder then collapses which generally takes the operator unawares and makes orientation in the bladder of the resection instrument more difficult. Undesired contact of the cutting blade with the bladder wall can also occur. When monitoring the bladder pressure care must thus be taken to not exceeding a maximum pressure and also to maintaining a minimum pressure which ensures that the bladder remains uncollapsed.

It is thus an objection of the present invention to provide a suprapubic flushing drain which simplifies the maintenance of the desired flushing pressure.

In accordance with the present invention there is provided a suprapubic flushing water drain for the discharge from a bladder of flushing water supplied to it from a transurethrally positioned resection instrument, the drain including a shaft defining a passage which communicates with atmosphere at or near the proximal end through an air opening, the passage further communicating with an overflow opening disposed between the air opening and the distal end of the shaft for connection to an outlet hose.

The shaft of the drain in accordance with the present invention merely has one passage and may thus be in the form of a simple tube. The single passage can thus have a large cross-section which is not prone to blockage. In use. the shaft will be substantially vertical and in the vicinity of its upper proximal end, e.g. either at the proximal end of the shaft or in the outlet hose in the immediate vicinity thereof, there is an overflow opening through which the flushing water 4 rising through the passage runs away. An air opening open to the atmosphere is provided above it. A water surface acted on by the atmosphere thus forms at the level of the overflow opening so long as water is supplied to the bladder through the supply passage. The water surface is always at the same height independent of the flow rate of the supply. Care must therefore merely be taken to ensure that the size of the overflow opening and of the outlet hose is sufficient to accommodate the maximum possible flushing water flow rate. The height of the water level above the bladder determines the pressure in it and the bladder pressure is thus always maintained constant. The magnitude of the supply flow rate does not influence the height of the water level. The supply flow rate can thus be regulated entirely in accordance with the requirements of the operator, which are principally to maintain a free field of view and to wash away waste from the operation. The drain thus automatically maintains the bladder pressure constant without the necessity of monitoring or controlling it. A fully automatic pressure control is thus provided with an extremely simple construction in which the bladder pressure is always maintained constant at the desired level independently of the flushing water supply rate without there being any possibility of an excessively high bladder pressure which strains the patient being reached or the bladder collapsing due to the bladder pressure becoming too low, which would impede the operator.

The drain preferably includes means which permit the vertical spacing of the overflow opening from the bladder to be adjusted. This feature permits the vertical spacing of the water level above the bladder to be adjusted and thus the bladder pressure to be matched to changing requirements.

The overflow opening in the shaft is preferably provided at an adjustable height, for instance by providing the shaft in telescopic, longitudinally adjustable form. More preferably a simple shaft is used which is connected to a mounting member, e.g. a mounting disc of the type which is commonly used, which, in use, engages the belly skin of the patient and which is movable and fixable longitudinally with respect to the shaft. In this manner the height of the water level above the bladder can be adjusted within the desired range by several centimetres.

It is preferred that the interior of the shaft communicates with a vessel disposed at or near the proximal end of the shaft whose cross-sectional area is greater than that of the shaft and which affords both the air opening and the overflow opening. The crosssection of the liquid passage is thus substantially enlarged in the vicinity of the overflow opening. This means that large variations in the flushing water flow rate or variations in the discharge flow rate in the outlet hose can only result in slight variations in the level of the water surface.

The vessel preferably comprises transparent material since this facilitates continuous visual observation of its contents. The magnitude of the proportion of blood in the water may thus be estimated in a simple manner and the flushing out of the pieces of tissue produced in'the operation may be observed.

Finally. the drain may include a photometer device associated with the vessel and arranged to respond to 6 the colour of the flushing water within the vessel. I This enables the flushing water in the vessel to be continuously photometrically checked, for instance examined colorimetrically with regard to the proportion of blood. The proportion of blood in the water may thus be indicated automatically. This provides valuable information to the operator regarding blood loss by the patient and permits the anaesthetist to i supply blood to the patient at the correct time.

One embodiment of the invention is illustrated schematically by way of example in the single accompanying drawing which is a sectional view through the bladder of a patient with a resection instrument and a flushing water drain in position.

The drawing is a longitudinal sectional view of a portion of the body of the patient in a lying position and shows the bladder with bladder wall 1, prostate 2, pubic bone 3 and belly skin 4.

An endoscopic resection instrument with a resection shaft S. from whose distal end a resection loop 6 projects, is introduced through the urethra (urine duct), which is not shown. At the proximal end of the resection shaft 5 there is an eyepiece 7 and a valve connection 8 to which a supply hose 9 is connected through which flushing water is supplied from a storage vessel 10 suspended at a high level. Water flows out of the storage vessel 10 through the hose 9 and a supply passage, which is not shown, in the resection shaft 5 into the bladder in which it flows approximately in the pattern indicated by the arrows. Work can be carried out with the resection instrument with a field of view that is constantly flushed clear in the region of the bladder, e.g. in the case of a

7 bladder wall carcinoma or particularly, in the region of the prostate 2,, e.g.in the case of a prostate resection.

The flushing water is discharged from the bladder through the shaft 11 of the suprapubic flushing water drain in accordance with the invention.

As a preparatory step, the shaft 11 is positioned in the illustrated position in the bladder in the usual manner with the aid of a trochar. It is thus situated in the pierced passage created by the trochar which leads from the exterior of the body above the pubic bone 3 through the belly skin 4 and intervening tissue and the bladder wall 1 into the interior of the bladder. The shaft 11 is essentially constructed as a hollow tube and is open towards the bladder at its distal, that is to say inner, end. In the illustrated embodiment the distal end is open to the bladder through a plurality of holes in the manner of a sieve. It could, however, alternatively have only a single hole.

The shaft 11 passes through a clamping ring 12 which carries a fixing screw 13 and is secured to a mounting disc 14 of larger diameter. The disc 14 rests on the belly skin 4 and thus maintains the shaft 11 in the illustrated, substantially perpendicular position and prevents it from tilting. After vertical adjustment of the shaft 11 with respect to the disc 14 into any desired vertical position it can be secured by means of the fixing screw 13.

At the upper proximal end of the shaft 11 and communicating with the passage within it there is a vessel 15 of larger diameter, whose wall is shown in section and, in this preferred embodiment, is 8 constructed of transparent material,, such as glass, acrylic or the like.

The vessel 15 is open to the atmosphere at its top by way of an air opening 16. which in the illustrated embodiment corresponds to the diameter of the vessel, and in its lateral wall has an overflow opening 17 to which an outlet hose 18 is connected. The hose leads, for instance, to a bucket placed under the operating table. The air opening 16 can be substantially smaller than that shown and thus, for instance, the top of the vessel 15 can be closed with a lid in which there is only a small air hole.

As mentioned above, flushing water is supplied to the bladder from the storage vessel 10 and then flows in the direction of the arrows shown in the bladder through the distal openings into the shaft 11. The water rises up the shaft 11 and runs finally through the overflow opening 17 and downwardly in the outlet hose 18. As shown in the drawing, a water surface 19 thus forms in the vessel 15 at the height of. the overflow opening 17. This surface remains stably at the illustrated height, that is to say the height of the overflow opening 17, under all circumstances. if the flushing water flow rate increasesi more water overflows and if it decreases less water overflows. The height of the water surface 19 above the bladder does not change since the air space above the bladder is in communication with the atmosphere through the air opening 16.

This construction also results in the water level 19 remaining at its desired height even if excessive suction should be applied to the outlet hose 18. Such excessive suction might otherwise tend to result in the h 9 bladder being largely or wholly emptied of water, which, if it occurred unexpectedly, could lead to undesired contact between, for instance. the resection loop and the bladder wall 1.

As mentioned above, the water level 19 thus remains under all circumstances at a constant height. Its vertical spacing from the bladder predetermines in an extremely simple manner the water pressure in the bladder which is thus always maintained constant automatically without the operator having to pay any attention to it. With an appropriate length of the shaft 11 the water pressure can thus be set very simply in the desired range of, for instance, 5 to 30cm water. If the water pressure is to be varied the fixing screw 13 is loosened and the shaft 11 slid upwardly or downwardly with respect to the mounting disc 14.

As mentioned above, the vessel 15 comprises a transparent material which permits its contents to be easily observed. In particular, it can be very easily and clearly determined visually how much blood there is in the outflowing flushing water. This information is of value to the operator and particularly to the anaesthetist who must supply blood to the patient if necessary. The monitoring of the colour of the flushing water can, if desired, be automated. For this purpose, a photometer 20,20 can be provided which transmits a light beam 21 through the vessel 15 and its contents and automatically determines the proportion of blood in a colorimetric manner and then provides an indication of it.

It will be appreciated that numerous modifications may be effected to the drain in accordance with the invention. Thus,, for instance, the overflow opening can be provided directly in the shaft without providing the vessel 15. The vertical adjustment of the overflow opening with respect to the bladder can be effected in a variety of ways, for instance by means of a telescopic longitudinally adjustable shaft. Finally, the air opening 16 and overflow opening 17 need not be provided directly at the distal end of the shaft 11. They can, for instance, be positioned in an arrangement adjacent the distal end of the shaft, e.g. beside it, or alternatively a portion of the shaft can be provided at a remote point in the outlet hose 18.

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Claims (7)

1. A suprapubic flushing water drain for the discharge from a bladder of flushing water supplied to it from a transurethrally positioned resection i.nstrument, the drain including a shaft defining a passage which communicates with atmosphere at or near the proximal end through an air opening, the passage further communicating with an overflow opening disposed between the air opening and the distal end of the shaft for connection to an outlet hose.

2. A drain as claimed in claim 1 including means which permit the vertical spacing of the overflow opening from the bladder to be adjusted.

3. A drain as claimed in claim 2 in which the shaf t is connected to a mounting member which, in use, engages the belly skin of the patient and which is movable and fixable longitudinally with respect to the shaft.

4. A drain as claimed in any one of the preceding claims in which the interior of the shaft communicates with a vessel disposed at or near the proximal end of the shaft whose cross-sectional area is greater than that of the shaf t and which af f ords both the air opening and the overflow opening.

5. A drain as claimed in claim 4 in which the vessel comprises transparent material.

12

6. - A drain as claimed in claim 4 or claim 5 including a photometer device associated with the vessel and arranged to respond to the colour of the flushing water within the vessel.

7. A suprapubic flushing water drain substantially as specifically 'herein described with reference to the accompanying drawing.

Published 1989 atThe PatentOMoe, State House, 88171 High Holborn, London WCIR 4TP. Further copies maybe obtained from The ?&tent Oftice. Wes Branch, St Max7 Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques Itd, St Mary Cray, Kent Con. 1/87