CA1086525A - Method of detecting infiltration of infused liquid by comparing altered skin temperature with skin temperature in area of infiltrated liquid - Google Patents
Method of detecting infiltration of infused liquid by comparing altered skin temperature with skin temperature in area of infiltrated liquidInfo
- Publication number
- CA1086525A CA1086525A CA266,919A CA266919A CA1086525A CA 1086525 A CA1086525 A CA 1086525A CA 266919 A CA266919 A CA 266919A CA 1086525 A CA1086525 A CA 1086525A
- Authority
- CA
- Canada
- Prior art keywords
- temperature
- skin
- liquid
- patient
- infusion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Abstract
METHOD OF DETECTING INFILTRATION OF INFUSED
LIQUID BY COMPARING ALTERED SKIN TEMPERATURE
WITH SKIN TEMPERATURE IN AREA OF INFILTRATED LIQUID
Abstract of the Disclosure Perivascular infiltration of liquid being administered to a patient is detected by the method of altering the temper-ature of a region of the patient's skin adjacent the site of a transcutaneous puncture and providing an output indicative of the difference between the altered skin temperature and the temperature of the infiltrated liquid.
LIQUID BY COMPARING ALTERED SKIN TEMPERATURE
WITH SKIN TEMPERATURE IN AREA OF INFILTRATED LIQUID
Abstract of the Disclosure Perivascular infiltration of liquid being administered to a patient is detected by the method of altering the temper-ature of a region of the patient's skin adjacent the site of a transcutaneous puncture and providing an output indicative of the difference between the altered skin temperature and the temperature of the infiltrated liquid.
Description
Back~round of the_Inventlon Intravenous administration of substantial quantities of liquids including water, electrolytes~ sugar, blood, pharma-ceuticals, and various nutritional materials are commonly administered to hospitalized patients from a glass or plastic container using a plastic tubing conduit which terminates in a needle that is inserted into a superficial vein or artery. A
patient's movements, however, may cause the tip of the needle to pierce the vascular wall and cause the liquid being adminis~
tered to fl-ow in the perivascular tissues. The liquid may accumulate and cause discoloration, discomfort and possible ~-~
destruction of tissues~ while precluding absorption into the metabolic pool of the materials being administered at the selected rate.
Prior liquid infusion infiltration detection apparatus and method (see, for example, U. S. Patent 3,618,602) permitted the early detection of liquid infiltrations so that corrective actions could be promptly instituted. In such prior apparatus and method, the skin temperature in the region overlying the 27 tip of the intravascular needle was continuously monitored.
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Since liquids adminis~ered to a patient are at room tempera-ture or refrigerated, they are typically at a lower temperature than normal skin temperature~ Thus~ any undesirable perivascular accumulation of administered liquid produces a decrement in skin temperature in the region overlying the accumulation. Since the temperatures of hospital rooms are typically about 20C.~25C.
and normal skin temperature is typically about 33C.~ a signifi-cant temperature difference commonly exists between infusion liquid and skin temperature to produce the change in skin temper-ature that signals the occurrence of an infiltration. However,it has been found in patients who are in a state of shock or who are undergoing, or have recently undergone, substantial surgery or anesthesia and in some small nurnber of other patients, blood flow to the skin may be sufficiently reduced that the patient's skin temperature tends to approximate the ambient temperature.
Under these conditions, a substantial difference between skin temperature and the temperature of the liquid being infused is not available to produce a substantial change in the temperature of the skin in a region thereof where perivascular infiltration of the infused liquid occurs. Also, in some circumstances (especially in tropical climates), hospital room temperatures may be elevated to levels approximating normal skin temperatures.
Under these circumstances 7 a substantial temperature difference between skin temperature and the temperature of the liquid being infused is again not available to produce a substantial change in the temperature of the skin in a region thereof where peri-vascular infiltration of the infused liquid occurs.
Summary of the Invention ~ -In accordance with one aspect of this invention there is provided infusion infiltration responsive apparatus for use ~6525 with liquid infusion equipment including a liquid-delivery conduit means terminating in an intravascular portion having a tip, said portion bein~ disposed to be inserted into a blood vessel of a patient, the apparatus comprising:
temperature-regulating means for altering the skin surface temperature o~ a patient in a selected region of skin overlying the intravascular tip of the liquid-delivery conduit means;
first sensor means disposed in thermal contact with ~ ;
the skin of the patient within said selected region overlying the intravascular tip of the liquid conduit means for providing an output indication representative of the temperature o-f the skin in thermal contact therewith; and circuit means responsive to the output indication from said first sensor means for providing an output indicative of the temperature sensed by said first sensor means. ;
In accordance with another aspect of this invention ;
there is provided the method of detecting liquid-infusion infiltration into the skin of a patient which is at a temperature not sufficiently different from the temperature of the liquid being infused, the method comprising the steps of~
placing a liquid-delivery conduit into a blood vessel of a patient for delivering an infusion liquid into a blood vessel of the patient;
. altering the patient's skin surface temperature relative to the temperature of the liquid in a region of the skin overlying the tip of the intravascular portion of the liquid conduit means; ~ ;~
and ,, .
; sensing the difference between the skin surface temperature due to the accumulation of the infused liquid in the perivascular region and the altered skin temperature for providing an output indicative of the difference between the two temperaturesO
- 2a -.,., j . . . , : : .
Description of the Drawinq Figure 1 is a pictorial diagram of the appliance used to regulate the patient's skin surface temperature and to detect changes in skin temperature; and Figure 2 is a schematic diagram of the illustrated embodiment of the present invention.
Description of the Preferred Embodiment Referring now to Figure 1, there is shown a flexible backing material 9 such as rubber-impregnated nylon, or the like, having a plurality of wires 11 attached thereto to form a heater that may be positioned on, or in close proximity to, a patient's skin~ as shown in ~igure 20 A heat-sensitive element 13 such as a thermistor is positioned in close thermal relationship to the heater 11 to provide an output indication on line 15 of the operating temperature thereof~ In addition, two sensing thermistors, or other heat-sensitive elements, 17 and 19~ are positioned within regions surrounded by the heater 11 to be positioned on, or in close proximity to, the patient's -skin for detecting the surface temperature thereof in two separated locations. Thermal conduction between the heater 11 and the sensors 17 and 19 via the backing material should be negligible.
, ,. ,: :, :
5;25 The appliance shown in ~igure 1 including heater 11 and sensors 13~ 17 and 19 may be positioned on a patient's skin~ as shown in Figure 2, in the region of the transcutaneous puncture :
by needle 21 with the thermal sensor 19 positioned on the skin overlying the region of the point of needle 21. In operation, the infusion set 23 may administer a liquid~ either by gravity flow or by positive displacement means~ via the flow control 25~
liquid conduit 27 and the needle 21 which is shown inserted into a blood vessel of a patient 20. The temperature of the liquid being infused is typically at or below room temperature (which~ ;
for most hospital rooms, is about 20 C.-25C., or cooler).
Normal skin temperature is generally at or about 33C.~ which is substantially different from the temperature of the liquid being infused. However, when patients are in a state of shock ;-or are undergoing~or have recently undergone~surgery or anesthesia or may be subjected to other conditions which substantially diminish skin blood flow~ the temperature of the skin drops to approximately the ambient temperature, which is generally cooler~
as noted above. In accordance with the present invention, when-ever such conditions tend to occur~ the local region of the patient's skin sur~ace adjacent the needle 21 is heated to elevate the skin temperature (say, to normal or somewhat above) ~
to assure adequate thermal difference between such local skin -~ -temperature and the temperature of the infused liquid. This heating is accomplished by applying electrical signal to the heater 11 from the heater controller 31. A heater driver 33 supplies signal to the heater 11 in response to the error signal that is derived ~rom the combination of signals from the reference .
. . .:
supply 35 and the sensor 13. The reference supply 35 may thus :~
be adjusted to set the heater current (and7 hence~ its temperature) . ' , ., at a selected value. ~lternatively~ the heater driver 33 may simply supply a ~electable current to heater 11 without the aid or bene~it o~ the servocontrol mechanism previously described.
In operation, the two heat sensors 17 and 19 are located within the heated region of the patient's skin surface and normally produce substantial equal output signals. However~
in the event the liquid being infused undesirably accumulates about the needle 21 in a perivascular region ràther than being properly administered into a blood vessel~ the liquid accumulation will alter the skin temperature in the region of sensor 19 The output signal due to this change in temperature may be compared in amplifier 36 with the output signal of sensor 17 or with the output of reference supply 37 of the sensing circuit 39. The reference signal from supply 37 or the output signal from sensor 17 will thus be representative of the elevated skin temperature (i.eO, about 35C.-3~C.)~ independent of the patient's condition.
If the ampli~ied difference signal on line 41 exceeds a selected value as determined by threshold detector 43, an output signal is produced on line 45 which may actuate an alarm 47 or actuate the flow controller 25 to terminate further liquid infusion, or both~ as described in said U. S. Patent 3~618~602 cited above.
Alternatively~ where the room or ambient temperature and the infusion liquid stored under such conditions may be elevated to approximate typical skin temperature~ as in tropical regions, or the like, the patient's skin surface temperature in the local region may be decreased below normal skin temperature ~;
rather than increased~ as previously described, to assure ade-~ quate thermal difference between such local skin region and the ; temperature of the infused liquid. This may be accomplished using electrically-powered Peltier~effect coolers or by .,~ . - .
. ~ ' ,"
circulating refrigerant or by expanding a compressed gas, or the like, in the local region of the skin surface. In this way7 the difference ~etween the temperature of the infused liquid and the temperature of the surface skin in the local region may be maintained large for rapid detection of perivascular infiltration 6 of the infused liquid.
.
~: . . ' ' ' ' ' '
patient's movements, however, may cause the tip of the needle to pierce the vascular wall and cause the liquid being adminis~
tered to fl-ow in the perivascular tissues. The liquid may accumulate and cause discoloration, discomfort and possible ~-~
destruction of tissues~ while precluding absorption into the metabolic pool of the materials being administered at the selected rate.
Prior liquid infusion infiltration detection apparatus and method (see, for example, U. S. Patent 3,618,602) permitted the early detection of liquid infiltrations so that corrective actions could be promptly instituted. In such prior apparatus and method, the skin temperature in the region overlying the 27 tip of the intravascular needle was continuously monitored.
~. . ' .
~ .:
. . : ., ~ - : . . . . .. .
. ~, - . ~ ,, , :
:: . ' .' ' '. -.~
::, ~: : , : .
: :
. ~ , . . .
;5~S
Since liquids adminis~ered to a patient are at room tempera-ture or refrigerated, they are typically at a lower temperature than normal skin temperature~ Thus~ any undesirable perivascular accumulation of administered liquid produces a decrement in skin temperature in the region overlying the accumulation. Since the temperatures of hospital rooms are typically about 20C.~25C.
and normal skin temperature is typically about 33C.~ a signifi-cant temperature difference commonly exists between infusion liquid and skin temperature to produce the change in skin temper-ature that signals the occurrence of an infiltration. However,it has been found in patients who are in a state of shock or who are undergoing, or have recently undergone, substantial surgery or anesthesia and in some small nurnber of other patients, blood flow to the skin may be sufficiently reduced that the patient's skin temperature tends to approximate the ambient temperature.
Under these conditions, a substantial difference between skin temperature and the temperature of the liquid being infused is not available to produce a substantial change in the temperature of the skin in a region thereof where perivascular infiltration of the infused liquid occurs. Also, in some circumstances (especially in tropical climates), hospital room temperatures may be elevated to levels approximating normal skin temperatures.
Under these circumstances 7 a substantial temperature difference between skin temperature and the temperature of the liquid being infused is again not available to produce a substantial change in the temperature of the skin in a region thereof where peri-vascular infiltration of the infused liquid occurs.
Summary of the Invention ~ -In accordance with one aspect of this invention there is provided infusion infiltration responsive apparatus for use ~6525 with liquid infusion equipment including a liquid-delivery conduit means terminating in an intravascular portion having a tip, said portion bein~ disposed to be inserted into a blood vessel of a patient, the apparatus comprising:
temperature-regulating means for altering the skin surface temperature o~ a patient in a selected region of skin overlying the intravascular tip of the liquid-delivery conduit means;
first sensor means disposed in thermal contact with ~ ;
the skin of the patient within said selected region overlying the intravascular tip of the liquid conduit means for providing an output indication representative of the temperature o-f the skin in thermal contact therewith; and circuit means responsive to the output indication from said first sensor means for providing an output indicative of the temperature sensed by said first sensor means. ;
In accordance with another aspect of this invention ;
there is provided the method of detecting liquid-infusion infiltration into the skin of a patient which is at a temperature not sufficiently different from the temperature of the liquid being infused, the method comprising the steps of~
placing a liquid-delivery conduit into a blood vessel of a patient for delivering an infusion liquid into a blood vessel of the patient;
. altering the patient's skin surface temperature relative to the temperature of the liquid in a region of the skin overlying the tip of the intravascular portion of the liquid conduit means; ~ ;~
and ,, .
; sensing the difference between the skin surface temperature due to the accumulation of the infused liquid in the perivascular region and the altered skin temperature for providing an output indicative of the difference between the two temperaturesO
- 2a -.,., j . . . , : : .
Description of the Drawinq Figure 1 is a pictorial diagram of the appliance used to regulate the patient's skin surface temperature and to detect changes in skin temperature; and Figure 2 is a schematic diagram of the illustrated embodiment of the present invention.
Description of the Preferred Embodiment Referring now to Figure 1, there is shown a flexible backing material 9 such as rubber-impregnated nylon, or the like, having a plurality of wires 11 attached thereto to form a heater that may be positioned on, or in close proximity to, a patient's skin~ as shown in ~igure 20 A heat-sensitive element 13 such as a thermistor is positioned in close thermal relationship to the heater 11 to provide an output indication on line 15 of the operating temperature thereof~ In addition, two sensing thermistors, or other heat-sensitive elements, 17 and 19~ are positioned within regions surrounded by the heater 11 to be positioned on, or in close proximity to, the patient's -skin for detecting the surface temperature thereof in two separated locations. Thermal conduction between the heater 11 and the sensors 17 and 19 via the backing material should be negligible.
, ,. ,: :, :
5;25 The appliance shown in ~igure 1 including heater 11 and sensors 13~ 17 and 19 may be positioned on a patient's skin~ as shown in Figure 2, in the region of the transcutaneous puncture :
by needle 21 with the thermal sensor 19 positioned on the skin overlying the region of the point of needle 21. In operation, the infusion set 23 may administer a liquid~ either by gravity flow or by positive displacement means~ via the flow control 25~
liquid conduit 27 and the needle 21 which is shown inserted into a blood vessel of a patient 20. The temperature of the liquid being infused is typically at or below room temperature (which~ ;
for most hospital rooms, is about 20 C.-25C., or cooler).
Normal skin temperature is generally at or about 33C.~ which is substantially different from the temperature of the liquid being infused. However, when patients are in a state of shock ;-or are undergoing~or have recently undergone~surgery or anesthesia or may be subjected to other conditions which substantially diminish skin blood flow~ the temperature of the skin drops to approximately the ambient temperature, which is generally cooler~
as noted above. In accordance with the present invention, when-ever such conditions tend to occur~ the local region of the patient's skin sur~ace adjacent the needle 21 is heated to elevate the skin temperature (say, to normal or somewhat above) ~
to assure adequate thermal difference between such local skin -~ -temperature and the temperature of the infused liquid. This heating is accomplished by applying electrical signal to the heater 11 from the heater controller 31. A heater driver 33 supplies signal to the heater 11 in response to the error signal that is derived ~rom the combination of signals from the reference .
. . .:
supply 35 and the sensor 13. The reference supply 35 may thus :~
be adjusted to set the heater current (and7 hence~ its temperature) . ' , ., at a selected value. ~lternatively~ the heater driver 33 may simply supply a ~electable current to heater 11 without the aid or bene~it o~ the servocontrol mechanism previously described.
In operation, the two heat sensors 17 and 19 are located within the heated region of the patient's skin surface and normally produce substantial equal output signals. However~
in the event the liquid being infused undesirably accumulates about the needle 21 in a perivascular region ràther than being properly administered into a blood vessel~ the liquid accumulation will alter the skin temperature in the region of sensor 19 The output signal due to this change in temperature may be compared in amplifier 36 with the output signal of sensor 17 or with the output of reference supply 37 of the sensing circuit 39. The reference signal from supply 37 or the output signal from sensor 17 will thus be representative of the elevated skin temperature (i.eO, about 35C.-3~C.)~ independent of the patient's condition.
If the ampli~ied difference signal on line 41 exceeds a selected value as determined by threshold detector 43, an output signal is produced on line 45 which may actuate an alarm 47 or actuate the flow controller 25 to terminate further liquid infusion, or both~ as described in said U. S. Patent 3~618~602 cited above.
Alternatively~ where the room or ambient temperature and the infusion liquid stored under such conditions may be elevated to approximate typical skin temperature~ as in tropical regions, or the like, the patient's skin surface temperature in the local region may be decreased below normal skin temperature ~;
rather than increased~ as previously described, to assure ade-~ quate thermal difference between such local skin region and the ; temperature of the infused liquid. This may be accomplished using electrically-powered Peltier~effect coolers or by .,~ . - .
. ~ ' ,"
circulating refrigerant or by expanding a compressed gas, or the like, in the local region of the skin surface. In this way7 the difference ~etween the temperature of the infused liquid and the temperature of the surface skin in the local region may be maintained large for rapid detection of perivascular infiltration 6 of the infused liquid.
.
~: . . ' ' ' ' ' '
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Infusion infiltration responsive apparatus for use with liquid infusion equipment including a liquid-delivery conduit means terminating in an intravascular portion having a tip, said portion being disposed to be inserted into a blood vessel of a patient, the apparatus comprising.
temperature-regulating means for altering the skin surface temperature of a patient in a selected region of skin overlying the intravascular tip of the liquid-delivery conduit means;
first sensor means disposed in thermal contact with the skin of the patient within said selected region overlying the intravascular tip of the liquid conduit means for providing an output indication representative of the temperature of the skin in thermal contact therewith; and circuit means responsive to the output indication from said first sensor means for providing an output indicative of the temperature sensed by said first sensor means.
temperature-regulating means for altering the skin surface temperature of a patient in a selected region of skin overlying the intravascular tip of the liquid-delivery conduit means;
first sensor means disposed in thermal contact with the skin of the patient within said selected region overlying the intravascular tip of the liquid conduit means for providing an output indication representative of the temperature of the skin in thermal contact therewith; and circuit means responsive to the output indication from said first sensor means for providing an output indicative of the temperature sensed by said first sensor means.
2. Infusion infiltration responsive apparatus as in claim 1 comprising:
second sensor means disposed in thermal contact with the skin of the patient within said selected region but remote from the tip of said intravascular portion for producing an output indication of the temperature of the skin in thermal contact therewith; and said circuit means is coupled to receive the output indications from said first and second sensor means for pro-viding said output indicative of the deviation in the skin temperatures sensed by said first and second sensor means.
second sensor means disposed in thermal contact with the skin of the patient within said selected region but remote from the tip of said intravascular portion for producing an output indication of the temperature of the skin in thermal contact therewith; and said circuit means is coupled to receive the output indications from said first and second sensor means for pro-viding said output indicative of the deviation in the skin temperatures sensed by said first and second sensor means.
3. Infusion infiltration responsive apparatus as in claim 1 wherein said temperature-regulating means includes apparatus for decreasing the skin surface temperature.
4. Infusion infiltration responsive apparatus as in claim 1 wherein said temperature-regulating means includes an electrical heater positionable on the skin of a patient for elevating the temperature within said selected region in response to electrical signal applied thereto.
5. Infusion infiltration responsive apparatus as in claim 4 comprising heater means coupled to said electrical heater for applying signal thereto to elevate the temperature of the skin within said selected region to a selected value.
6. Infusion infiltration responsive apparatus as in claim 5 comprising:
third sensor means thermally coupled to said electrical heater for providing an output indicative of the temperature of the electrical heater; and said heater means includes means responsive to the output from said third sensor means for controlling the signal applied to said electrical heater to maintain the temperature of skin in said selected region substantially constant at about said selected value.
third sensor means thermally coupled to said electrical heater for providing an output indicative of the temperature of the electrical heater; and said heater means includes means responsive to the output from said third sensor means for controlling the signal applied to said electrical heater to maintain the temperature of skin in said selected region substantially constant at about said selected value.
7. The method of detecting liquid-infusion infiltration into the skin of a patient which is at a temperature not suf-ficiently different from the temperature of the liquid being infused, the method comprising the steps of:
placing a liquid-delivery conduit into a blood vessel of a patient for delivering an infusion liquid into a blood vessel of the patient;
altering the patient's skin surface temperature relative to the temperature of the liquid in a region of the skin overlying the tip of the intravascular portion of the liquid conduit means;
and sensing the difference between the skin surface temperature due to the accumulation of the infused liquid in the perivascular region and the altered skin temperature for providing an output indicative of the difference between the two temperatures.
placing a liquid-delivery conduit into a blood vessel of a patient for delivering an infusion liquid into a blood vessel of the patient;
altering the patient's skin surface temperature relative to the temperature of the liquid in a region of the skin overlying the tip of the intravascular portion of the liquid conduit means;
and sensing the difference between the skin surface temperature due to the accumulation of the infused liquid in the perivascular region and the altered skin temperature for providing an output indicative of the difference between the two temperatures.
8. The method according to claim 1 wherein the step of altering the patient's skin surface temperature is accomplished by heating said region of the patient's skin to a temperature above the temperature of the liquid.
9. The method according to claim 1 wherein the step of altering the patient's skin surface temperature is accomplished by cooling said region of the patient's skin to a temperature below the temperature of the liquid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA266,919A CA1086525A (en) | 1976-11-30 | 1976-11-30 | Method of detecting infiltration of infused liquid by comparing altered skin temperature with skin temperature in area of infiltrated liquid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA266,919A CA1086525A (en) | 1976-11-30 | 1976-11-30 | Method of detecting infiltration of infused liquid by comparing altered skin temperature with skin temperature in area of infiltrated liquid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1086525A true CA1086525A (en) | 1980-09-30 |
Family
ID=4107402
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA266,919A Expired CA1086525A (en) | 1976-11-30 | 1976-11-30 | Method of detecting infiltration of infused liquid by comparing altered skin temperature with skin temperature in area of infiltrated liquid |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1086525A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107589210A (en) * | 2016-07-07 | 2018-01-16 | 株式会社岛津制作所 | Liquid chromatograph column oven and liquid chromatograph |
-
1976
- 1976-11-30 CA CA266,919A patent/CA1086525A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107589210A (en) * | 2016-07-07 | 2018-01-16 | 株式会社岛津制作所 | Liquid chromatograph column oven and liquid chromatograph |
| CN107589210B (en) * | 2016-07-07 | 2020-01-03 | 株式会社岛津制作所 | Column oven for liquid chromatograph and liquid chromatograph |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |