INFUSION PRESSURE CONTROL SYSTEM

Abstract

An infusion pressure control system for ophthalmic surgery includes intraocular pressure detection means, arterial pressure detection means and a control unit operatively connected to the intraocular pressure detection means and the arterial pressure detection means and configured for calculating the mean ocular perfusion pressure value based on intraocular pressure and arterial pressure values provided by the intraocular pressure detection means and by the arterial pressure detection means, and for comparing the calculated mean ocular perfusion pressure value and at least one predetermined threshold value.

Claims

1. An infusion pressure control system for ophthalmic surgery, the system including: intraocular pressure detection means; arterial pressure detection means; and a control unit operatively connected to said intraocular pressure detection means and said arterial pressure detection means and configured for calculating a mean ocular perfusion pressure value based on intraocular pressure and arterial pressure values provided by said intraocular pressure detection means and by said arterial pressure detection means, and for comparing said calculated mean ocular perfusion pressure value and at least one predetermined threshold value.

2.0 The system of claim 1, wherein the control unit is configured to generate an alarm signal if the calculated mean ocular perfusion pressure value is below the predetermined threshold value.

3. The system claim 1, further comprising an electromedical apparatus adapted to be connected to a patient at least by an infusion line suitable for dispensing an infusion fluid at an infusion pressure, said electromedical apparatus being adapted to allow adjustment of an infusion pressure.

4. The system of claim 1, wherein said intraocular pressure detection means comprise an intraocular pressure sensor.

5. The system of claim 1, wherein said intraocular pressure detection means are suitable for calculating the intraocular pressure value based on a pressure value and, optionally, an infusion flow of an infusion fluid.

6. The system of claim 3, wherein the electromedical apparatus is a phacoemulsifier or a phacovitrectomer.

7. The system of claim 3, wherein the infusion line comprises a gravitational or forced infusion system by pressurizing a vessel containing the infusion fluid.

8. The system of claim 1, wherein arterial pressure detection means include a pressure gauge suitable to be connected to a patient.

9. The system of claim 1, wherein the arterial pressure detection means are connected to the control unit via a wireless communication system.

10. The system of claim 3, wherein the control unit is configured to command the infusion line to reduce the infusion pressure if the value of the calculated mean ocular perfusion pressure is below the predetermined threshold value.

11. The system of claim 3, wherein the electromedical apparatus is provided with an operator interface suitable to allow a manual infusion pressure adjustment.

12. The system of claim 1, wherein the mean ocular perfusion pressure value is calculated continuously or at predetermined time intervals.

13. The system of claim 1, wherein the mean ocular perfusion pressure (MOPP) value is calculated using the formula:
MOPP=115/130 MAPIOP, or using the formula:
MOPP=MAPIOP, wherein MAP indicates mean arterial pressure calculated according to the formula MAP= SBP+ DBP, and IOP indicates the intraocular pressure.

14. The system of claim 1, wherein the control unit comprises a timer operatively linked to an alarm, the timer being incrementable and decrementable based on comparing the calculated mean ocular perfusion pressure value and at least one predetermined threshold value, the alarm being activated when the timer exceeds a predetermined timer threshold value.

15. The system of claim 1, wherein the control unit comprises or is operatively linked to a graphic interface suitable for displaying an alarm message or an indicator capable of generating an audible signal if an average pressure value of the calculated mean ocular perfusion pressure is lower than the predetermined threshold value.

16. The system of claim 1, wherein the control unit comprises or is operatively connected to a user interface suitable for receiving a consent command from an operator, said consent command being suitable to enable an infusion pressure adjustment.

17. system of claim 3, wherein the infusion pressure is adjustable by varying a height of a reservoir containing the infusion fluid.

18. The system of claim 3, wherein the infusion pressure is adjustable by varying a controlled overpressure in use upstream of the infusion fluid.

Description

[0063] The features and the advantages of the infusion pressure control system and method according to the invention shall be made readily apparent from the following description of preferred embodiments thereof, provided purely by way of a non-limiting example, with reference to the accompanying figures, in which:

[0064] FIG. 1 is a graph showing some MOPP curves as a function of the IOP relative to subjects with different blood pressure values;

[0065] FIG. 2 is a graph showing the trend of some characteristic pressures during an ophthalmic surgery;

[0066] FIG. 3 is a schematic representation of the infusion pressure control system according to the invention;

[0067] FIG. 4 is a flowchart of an example of infusion pressure regulation logic according to the present invention; and

[0068] FIG. 5 is an example of a graphical user interface for the representation and regulation of the infusion pressure.

[0069] With reference to FIG. 3, reference numeral 1 diagrammatically shows a patient to whom a blood pressure meter 4 is connected.

[0070] The blood pressure data is sent to an electromedical apparatus 7.

[0071] An intra-ocular pressure meter 5 allows direct detection of the intraocular pressure (IOP). The intraocular pressure data is transmitted to the electromedical apparatus 7.

[0072] If the conditions foreseen by the regulation logic are met, the control unit of the electromedical apparatus 7, for example after receiving the authorization by the surgeon, commands pressure control means 6. These pressure control means 6 intervene on the infusion line 3, varying the pressure of the infusion fluid contained in the reservoir 2, until the value of the MOPP is brought back within the safety limits.

[0073] FIG. 4 describes the flow chart of the infusion pressure regulation method.

[0074] Initially, the intraocular pressure (IOP) is measured (step 10). This can be determined once the position of the reservoir 2 with the irrigation fluid is known or can be measured with a pressure sensor connected to the patient's eye.

[0075] Subsequently, blood pressure (BP) is measured (step 12).

[0076] By combining the IOP and BP pressure values, the system calculates the MOPP and provides it to the surgeon via the user interface (step 14). The MOPP is then compared to a threshold value (step 16).

[0077] If the MOPP is greater than the threshold value, the infusion pressure is not reduced (step 18).

[0078] The status of the alarm is then checked (step 20). If the system alarm is not active, the cycle returns to the beginning.

[0079] If the system is in alarm, the alarm is stopped (step 22). The cycle starts again after decreasing the alarm timer, if this was greater than zero (step 24).

[0080] If the MOPP is lower than the threshold value, the system goes into an alert state (step 26) and the alarm timer is increased (step 28).

[0081] The alarm timer is then compared to a timer threshold value (step 30).

[0082] If the alarm timer is greater than the threshold value, the system triggers an alarm (step 32), otherwise it returns to the beginning of the cycle.

[0083] If the alarm is active, the consequent adjustment of the infusion pressure (step 36) may be subject to the authorization of the surgeon which is carried out through the user interface of the electromedical apparatus (step 34).

[0084] FIG. 5 shows an example of a user interface suitable for showing the infusion pressure to the surgeon for maintaining the ideal ocular pressure for a correct Mean Ocular Perfusion Pressure (MOPP) and allowing pressure regulation.

[0085] The button for setting the infusion pressure is indicated with reference numeral 40; the indicator of the current infusion pressure value is indicated with reference numeral 41. Zone 42, for example colored green, around indicator 41 indicates the range of infusion pressures that cause an optimal MOPP; zone 44, for example colored red, indicates the zone of infusion pressure which generates a definitely insufficient MOPP; zone 46, for example colored yellow, indicates an alarm zone but not of immediate danger.

[0086] A man skilled in the art may make several changes, adjustments, adaptations and replacements of elements with other functionally equivalent ones to the embodiments of the infusion pressure control system and method according to the invention in order to meet incidental needs, without departing from the scope of the following claims. Each of the features described as belonging to a possible embodiment can be obtained independently of the other embodiments described.