Femoral compression device

Abstract: The present invention relates to a femoral compression device (1) comprising an operating means (5) for compressive bearing on the femoral artery of a patient subjected to, for example, heart catheterisation and for applying a pressure on the same. The operating means (5) is pressure tight arranged in a base plate (2) being fastened at the patient by a belt (3), which is locked by a locking device (4), whereby the operating means (5) bears on the puncture site. The compressive force against the compression site in set by inflating the operating means (5) via a connection (6) in the base plate (2). To perform hemostatis of the femoral artery of a patient the operating means (5) is laid against the puncture site and fastened towards this in that a belt (3) enclosing the body of the patient is pulled tight and secured by a locking device (4), in that the balloon is inflated to a pressure being at a determined value between the diastolic and syslotic pressure level, in that the blood flow down to the leg and foot is registrated by measuring the pulse downstream of the puncture site. Any bleeding can be observed through the transparent operating means (5) and the base plate (2).

Description: The present invention relates to a femoral compression device comprising a pressurizing means to bear on the femoral artery. To be able to visualize arteries with contrast medium during, for example, heart catheterisation, one oftens enters via the femoralis artery in the groin. Today an investigation like that is performed in that a small incision is made in the femoral artery using a small diameter cannula. A guide is inserted into the canulla and into the artery and thereafter a catheter is threaded over the guide into the artery. Thereafter the guide is removed and contrast medium is injected through the catheter into the artery. After completed investigation the catheter is drawn out and the bleeding from the incision site in the femoral artery is stopped. This can be done manually, ie the physician presses the finger against a compressive bandage laid on the wound for about 20 minutes. Obviously this is not a satisfactory method since it is inconvenient for both patients and physicians and also require valuble physician time. Furthermore, it is difficult for the physician to maintain a constant pressure force. Several devices have also been proposed by which a pressure is applied onto the wound in the femoral artery. US A 4 509 528 describes an hemostat with blood flow sensor. The sensor 21 measures the blood flow and can be of, for example, Doppler type. The signal from the sensor is processed by a signal processor 24 producing a second signal, preferably a sound, varying in volume in response to changes in the blood flow through the blood vessel. This arrangement is well known and desribed earlier. When the sound, and thus also the blood flow, varies the latter is to be reset manually by a number of adjustments. Thus there exist no feed back from the sensor to the operating means. US 4 770 175 describes a device for occluding blood flow into a digit and not to regulate the same. The device is provided with a pressurizing means 20 and a sensor sensing the pressure excerted by the means 20 against the digit. The signal from the sensor is digitally processed and thereafter a signal goes to the pressurizing means in such a way that a constant, occluding pressure always acts on the digit. Thus the device does not comprise a sensor measuring blood flow. The shown Doppler device 64 is only used to obtain standard curves to establish occluding pressure levels for different cuff and digit dimensions. In US 3 625 219 there is shown a device for hemostasis in which an inflatable balloon is used as pressurizing means. However this device involves a complex and instable construction and does not allow patient movement. Like the above devices, this one does not comprise a feed back from the sensor to the pressurizing means. The principle of these devices is the same, ie that a pressure is applied on the incision site in the femoral artery for about 20 minutes following completed catheterisation. The pressure is to be set as high as possible to stop bleeding but not as high that the blood flow down to the leg and foot is cut off. Following ballon dilatation of the femoral artery in the leg it is especially important not to apply too high pressure on the incision site as there is a risk that the dilated stenosis in the artery will contract if the blood pressure is too low. To avoid blood clots the patients are given anti coagulating agents, such as heparin, prior to the treatment. This of course extends the time required to stop the bleeding after having completed the method. For patients already taking heparin of medical reasons, the time will be as long as up to 1,5 hours. Hematoma is the most common side effect due to insufficient compression of the femoral artery. Therefore the object of the present invention was to provide a femoral compression device which is more reliable than and avoids the disadvantages of prior art. Another object was to provide a device which is more comfortable and gives greater freedom of movement for the patients. These objects are achieved by a femoral compression device according to claim 1. The invention will now be described with further detail below with reference to the accompanying drawings, in which Fig. 1 is a schematic view of a femoral compression device not according to the invention; Fig. 2 shows a preferred embodiment of the femoral compression device according to the invention; Fig. 3 is a section view of the femoral compression device according to Fig. 2 applied on a patient; Fig. 4 is a schematic view of femoral compression device comprising an electronic control unit; and Fig. 5 is a schematic view of femoral compression device comprising an electronic control unit and a sensor. Fig. 1 shows a femoral compression device 1 comprising a pressurizing means 5 for compressive bearing at the puncture site, preferably located at the femoral artery of a patient subjected to, for example, heart catheterisation, and for applying a pressure on the same, and a base plate 2 for supporting said pressurizing means. The device 1 comprises a belt 3 adapted to be fixed around the patient's body. The base plate 2 has a top portion and a bottom portion and is adapted to be fixed to the belt 3. The pressurizing means 5 is provided at the bottom portion of the base plate 2 so as to excert a compressive force against the patient's body at the puncture site. The base plate 2 can be integrated with the belt 3 as shown in Fig. 1. The base plate 2 is made of hard plastic or metal and is intended to be secured over the femoral puncture site of the treated patient by the flexible belt 3 enclosing the body of the patient at the hip area. The belt 3 is locked by a locking device 4; in the shown embodiment this is of Velcro® tape. On the lower side of the base plate 2 the pressurizing means 5 is pressure tight arranged being in the form of a semi spherical balloon. The balloon 5 is preferably made of a soft plastic, elastomere or mixture thereof and is optionally reinforced, eg with fabric. The material of the balloon should have maximum flexibility and minimum creep. The plastic can be of PVC being easily resilient with a constant inner overpressure, or of Mylar® film being only slightly resilient with a constant inner overpressure. In the shown embodiment the base plate is circular but it can of course also take other forms, eg square, rectangular or oval. In the top portion of the base plate 2 a connection 6 is arranged for inflating the balloon 5. To enable visual observation of bleeding, the balloon and a part of or the whole base plate 2 are made of transparent material. The base plate 2 can be integrated in the belt 3 or form a separate unit. Fig. 2 shows a preferred embodiment of the present invention. The features that differ this embodiment from the above described is that the top portion of the base plate 2 comprises extension means 2a, 2b extending in opposite directions and being provided with locking means 4 in the ends thereof for insertion of a respective end of the belt 3. The extension 2a is shorter than the extension 2b, the extensions preferably being arc shaped and disposed at an elevated position in relation the base plate 2. A balloon 5 is fastened in the bottom side of the base plate 2 in the same manner as in Fig. 1. A belt 3 is fastened in the outer ends of the extensions 2a, 2b by a self locking device 4 having a greater width than the extensions 2a, 2b. The width of the locking means generally corresponds to the width of belt 3 being broad to compensate for imbalance of the device. Imbalance is also compensated for by the extended shape of the base plate 2 in that it gives the balloon 5 a stable base. This embodiment is especially comfortable for the patient as it allows some movement of the patient without changing the balloon position. Furthermore the device can be left on the patient after completed hemostasis instead of a conventional compressive bandage. In this figure there is also shown a tubing 6a connecting the connection 6 to a pump 7 having a pressure gauge 8. The cross section according to Fig. 3 shows the device according to Fig. 2 mounted on a patient. As appears the arc shaped extensions 2a, 2b provide clearance beneath the device, and this design makes the device more comfortable for fat patients. The short extension 2a is to be put on the artery side of the patient and the longer extension 2b on the other side of the patient. Alternatively the base plate 2 is telescopically designed enabling it to be adjusted to different body widths. The pressurizing means 5 can also be designed as a truncated cone to decrease the pressure surface against the body. To obtain an even more selective pressure on a small surface the pressure surface is provided as a stiff portion, for example ten times thicker than the rest of the pressurizing means 5. This latter embodiment will function as a pneumatic air cylinder. Furthermore, the pressurizing means can be provided with accordion foldings in the upper portion closest to the base plate 2 to increase the effective stroke length thereof. This also eliminates the risk that the partially inflated balloon will be folded at the pressure surface against the skin, which at continued expansion of the balloon results in friction and therefore possible discomfort for the patient. Following completed catheterisation via the femoral artery, the balloon 5 is laid against the puncture site and tightened against this by tightening the belt 3 and securing it by the locking device 4. The balloon 5 is inflated by the pump 7 via the connection 6 and tubing 6a to a pressure being at a determined value between the diastolic and systolic pressure level read on the pressure gauge 8. A tissue pressure is excerted about the artery being slightly lower than the systolic pressure which results in maintaining the correct blood flow. The inflation of the balloon 5 can be done manually like in Fig. 2 or automatically as decribed below. The blood flow down to the leg and foot can be registrated by measuring the pulse downstream of the puncture site. If the pressure is too low blood will flow out of the puncture site which can be observed through the transparent balloon 5 and base plate 2. Fig. 4 shows the femoral compression device in assocation with an electronic control unit 10 comprising a driving means, such as a pump. Optionally the electronic control unit can be provided with a pressure gauge. This embodiment is constructed as an automatic regulating device in which selected pressure values and times etc. can be programmed into the electronic control unit 10 for sequentially applying different pressures on the artery. After about 20 minutes, for example, the initial hemostasis pressure must be decreased and the automatic regulating device gives extra security in case the nursing personell are absent at that time. The automatic regulating device also compensates for any creep relaxations in the plastic of the balloon 5 and any leakage in the system. The degree of inflation of the balloon 5 is controlled pnuematically or hydraulically via the driving means. Filling and emptying of the balloon 5 results in that the balloon is pressed against and from the puncture site, respectively. A method for hemostasis of the femoral artery of a patient following, for example, heart catheterisation, comprises the steps of: applying a reference pressure over the puncture site; applying an additional pressure over said puncture site; monitoring the sum of said reference pressure and said additional pressure; gradually reducing said additional pressure over a prolonged period of time; and releasing said reference pressure when said hemostasis is fully completed. In an alternative embodiment one also registrates the pulsations of the pressure medium in the balloon 5 being created by the pulse of the patient. The pulsations occur only between the systolic and diastolic pressure values. If no pulse can be registrated, indicating that the blood flow through the artery is too high or too low, the electronic control unit 10 triggers an alarm calling for the attention of the nursing personell. This embodiment guarantees that the balloon always is correctly positioned. In a modification of the above embodiment the pulsations in the pressure medium of said pressurizing means 5 caused by the pulse of the patient are registrated and processed by said electronic control unit 10. The driving means is responsive to signals from said electronic control unit 10 in such a way that the selected pressure value is constantly maintained or updated dependent on the registrated pulsation value. Thus, this embodiment provides a feed back from the pressurizing means to the electronic control unit. In the method according to this embodiment, the monitoring step further comprises registration of pulsation values caused by the patients pulse at said puncture site and comparing said pulsation values with selected values and controlling said additional pressure dependent on said registrated pulsation values. In the embodiment shown in Fig. 5 an external sensor 9 disposed at or downstream of the compression site detects actual blood pressure in the artery and reports the detected actual blood pressure values to the electronic control unit 10 for comparison with a selected pressure value. The driving means is responsive to signals from the electronic control unit 10 in such a way that the selected pressure value is constantly maintained or updated dependent on the detected actual blood pressure value. In the method according to this embodiment, the monitoring step further comprises registration of actual blood pressure values at or downstream of said puncture site and comparing said actual blood pressure values with selected values and controlling said additional pressure dependent on said registrated actual blood pressure values. The position of the sensor 9 is not critical but should be at or downstream of the actual press site; naturally it need not be disposed within the pressurizing means 5 but can also be arranged separetely. Data from the sensor 9 can be read on a monitor 11 which is also provided with speakers (not shown) alarming if the flow is too high because the pressurizing means 5 has been moved out of position. The flow can also be adjusted manually in emergency cases by an adjusting wheel 12 on the monitor 11. The sensor 9 can be a microphone detecting the Korotkoff-sound, ie the sound created by turbulence in arteries when the applied pressure is between the systolic and diastolic pressure levels of the patient, or an ultrasonic Doppler detecting the blood flow. However, we have found that sensors for measuring blood flow, such as the Doppler devices existing today, cannot be used to satisfactorily perform hemostasis of the femoral artery because of its deep position and the low blood flows therein. When setting the pressurizing means 5 against the compression site, ie the groin skin and underlaying femoral artery, it is pushed downwardly until the sensor 9 detects the systolic pressure level, ie the Korotkoff-sound. Thereafter the electronics regulates the applied pressure to a determined value under the systolic pressure in a certain number of percent units. This pressure level is updated or maintained constantly and the method according to the invention regulates independently of the absolute pressure values of the patient. Optionally there is also arranged an optic sensor (not shown) which senses if bleeding starts and sends signals to the electronic control unit 10. The reflectance from the skin is detected by a light source and a detector. The optic sensor operates at two wave lengths, one that detects blood on the skin, and another that detects if the patient becomes blue as a result of a bleedning beneath the skin. Any colour changes of the skin results in an alarm sound in the speakers being controlled by the electronic control unit 10.

Claims: Femoral compression device (1) comprising a pressurizing means (5) for compressive bearing at a puncture site at a femoral artery of a patient, and for applying a pressure on said puncture site, a belt (3) adapted to be fixed around the patient's body, a base plate (2) for supporting said pressurizing means, characterized in that said base plate (2) has i) a top portion having a plurality of extensions, including first and second extensions (2a, 2b) extending in opposite directions, disposed at an elevated position in relation to the top portion of the base plate, and provided with locking means (4) in the ends therof for insertion of an end of the belt (3); and ii) a bottom portion connected to the pressurizing means (5); and in that the pressurizing means (5) and the base plate (2) at least partially are made of a transparent material, to permit viewing of the puncture site therethrough. Femoral compression device according to claim 1, characterized in that said base plate (2) is integrated with said belt (3). Femoral compression device according to claim 2, characterized in that said first extension (2a) is shorter than said second extension (2b), the extensions being arc shaped. Femoral compression device according to any of claims 2-3, characterized in that said extensions (2a, 2b) of said base plate (2) are telescopically adjustable. Femoral compression device according to claims any of 3-4, characterized in that the width of the locking means (4) generally corresponds to the width of said belt (3). Femoral compression device according to claims any of 1-5, characterized in that the top portion of said base plate (2) is provided with a connection (6) for connecting a tube (6a) to a driving means for generating a controlled pressure with said pressurizing means (5). Femoral compression device according to any of claims 1-6, characterized in that said pressurizing means (5) is shaped like a semi spherical balloon. Femoral compression device according to any of claims 1-6, characterized in that said pressurizing means (5) is shaped like a truncated cone. Femoral compression device according to claim 8, characterized in that the pressure surface of said truncated cone is stiffer than the rest of said pressurizing means (5). Femoral compression device according to one or more of the preceding claims, characterized in that said pressurizing means (5) and a part of or the whole of said base plate (2) is made of a transparent material, such as plastic, elastomere or mixture thereof, optionally being reinforced. Femoral compression device according to one or more of the preceding claims, characterized in that said pressurizing means (5) is provided with accordion foldings in the upper portion closest to said base plate (2) to increase the effective stroke length of said pressurizing means.

Inventors: AKERFELDT DAN, SIGWART ULRICH, AKERFELDT, DAN, SIGWART, ULRICH
Applicants: RADI MEDICAL SYSTEMS, RADI MEDICAL SYSTEMS AB
Application year: 1991
Main classification: A61B17
IPC codes: A61B17, A61M25