Thermogard XP Physicians Manual Rev 3

Physician Manual Rev. 3 Copyright © 2011 ZOLL Circulation, Inc. All rights reserved. Printed in U.S.A.

Trademarks Alsius, CoolGard, CoolGard 3000, Thermogard XP, IVTM, Cool Line, Solex, Quattro, and Icy are registered trademarks of ZOLL Circulation, Inc. Mallinckrodt is a registered trademark of Mallinckrodt Inc. Windows is a registered trademark of Microsoft Corporation. Other products and names listed in this document may be trademarked by their owners and no representation is made by ZOLL Circulation, Inc. as to rights thereto.

ZOLL Circulation, Inc 650 Almanor Avenue Sunnyvale, California U.S.A. Telephone: Facsimile:

+1-408-541-2140 +1-408-541-1030

ZOLL IVTM™ System

Physicians' Manual

Contents Introduction 5 Scope 5 Cool Line Catheter - Indications for Use 6 Warning – Fever Reduction 6 Icy, Quattro and SolexCatheters - Indications for Use 6

Thermoregulation 7 Normal Control of Body Temperature 7 Central Set-Point 7 Peripheral Responses 8 Summation of Peripheral and Central Sensory Signals 8 Increased Body Temperature 8 Thermal Regulation and Disease States 8 Pyrogens 8 Cerebral Injury 9

This Product in its Environment 10 Introduction 10 Treatment Algorithms 10 Max Power (MAX) 10 Controlled Rate 10 FEVER (FVR) 11 Warming (Warm) 11 The Patient Environment 11

Cool Line Catheter 13 Fever Management – The Standard of Care 13 Standard Methods of Fever Reduction 13 Fever Reduction Clinical Study 14 Clinical Study Summary 14 Objective: 14 Materials and Methods: 14 Results: 14 Clinical Study Results in Detail 15 Significant Reduction in Fever Burden 15

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Complications 17 Specific Use Effects 19 Obvious Fever 19 Masked Fever vs. Steady State 19 In Summary 20

Icy, Quattro & Solex Catheters 21 Cardiac Surgery 21 Afterdrop 21 Fast-Track Recovery After Cardiac Surgery 21 Rewarming Post-Cardiac Surgery 22 Neurosurgery 22 Operative Hypothermia 22 Rewarming 23 Catheter Selection 23 Specific Use Effects 25 Cardiac Function 25 Bradycardia 25 Arrhythmia 25 Lung Function 26 Sepsis 26 Infection 26

General Risks of Central Line Usage 27 Caveats to CVC Placement (CVC-WG) 27 Infection 28

Specific Operational Issues 30 Stop the Pump 30 Air Bubble Detector 30 Fluid Loss Detector 31 To check the integrity of the catheter: 31 To check the integrity of the tubing set: 31 Cool Line Catheter – Two Functions 32 Seven Days – Cool Line Catheter Only 32 “Dead Head” Pressure 32 Water and Propylene Glycol 32 Dual Temperature Probes 33 Single Use/Service Life 33

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Check the Pinwheel 33

References 34

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Introduction Scope This manual applies to the ZOLL Intravascular Temperature Management (IVTM™) System which consists of both the CoolGard 3000® and the Thermogard XP® Consoles and IVTM Catheters. It is intended to provide pertinent clinical information to physicians as they use the IVTM System. This manual should be read in conjunction with the Operation Manual for the IVTM System. It is not intended to provide sufficient information to the untrained user to understand the safe operation of the IVTM System. Please consult the Operation Manual for the IVTM System and the Instructions For Use for the IVTM Catheters prior to use.

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Cool Line Catheter - Indications for Use ®

The IVTM System and Cool Line Catheter is indicated for use in fever reduction, as an adjunct to other antipyretic therapy, in patients with cerebral infarction and intracerebral hemorrhage who require access to the central venous circulation and who are intubated and sedated.

Warning – Fever Reduction The safety of this device has not been demonstrated for fever reduction in patients presenting with subarachnoid hemorrhage or primary traumatic brain injury. The safety and effectiveness of this device was examined in a randomized controlled trial of 296 patients. The mortality results reported in this trial, for the four patient cohorts enrolled, are presented in the table below (CI – cerebral infarction, ICH – intracerebral hemorrhage, PTBI – primary traumatic brain injury, SAH – subarachnoid hemorrhage). Mortality by Diagnosis (ITT) Cool Line

Control

n

N

%

n

N

%

p-value*

CI

3

16

18.8

3

14

21.4

0.74

ICH

8

33

24.2

7

27

25.9

1.00

PTBI

10

44

22.7

4

38

10.5

0.24

SAH

13

61

21.3

7

63

11.1

0.15

*Fischer’s exact test For more details on the results of this study please refer below to the section on Clinical Experience.

Icy , Quattro & Solex Catheters - Indications for Use ®

®

®

The IVTM System, using either the Icy , Quattro or Solex Catheters, is indicated for use:

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in cardiac surgery patients to achieve and or maintain normothermia during surgery and recovery/intensive care, and,

•

to induce maintain and reverse mild hypothermia in neuro surgery patients in surgery and recovery/intensive care.

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Thermoregulation Human beings are mammals: as such their physiology operates to set and maintain o o body temperature within a narrow band about a set-point, nominally 37 ± 1 C.

Normal Control of Body Temperature1 The body temperature is a reflection of the equilibrium state between the body and its o o environment. Within an environmental range of approximately 13 C to 54 C, a normal o unclothed human can maintain a core body temperature somewhere between 36 C o and 37.9 C [1]. Heat is generated within the body via chemical and physical processes of the body. The physical processes include both bodily activity and cellular respiration. Heat is a byproduct of cellular respiration–most of this heat is generated in skeletal muscle and, to a lesser extent, in brown fat and in the liver. Seventy five percent or more of total energy input is released back to the environment directly as heat (depending upon the level of physical activity). Shivering is a specific example of muscular activity to produce heat. Heat loss is via conduction to materials in direct contact with the body, via convection to the air, and via infrared emissions. We use clothing to help minimize this heat loss. Respiration and sweating are specific evaporative/ convective mechanisms (heat is conducted to the surface layer of water where it then drives a phase change–the movement of unsaturated air accelerates the process); the latter being specifically variable in response to body temperature. Typical sources of human heat loss in a room at normal temperatures are shown in the table below [1]. Table 1. Human Heat Loss by Source. Source

Percent Radiation

60%

Evaporation

22%

Conduction to objects

3%

Convection/conduction to air

15%

In general, humans have a central control mechanism that seeks to maintain body temperature in reference to a set-point. This set-point can be varied by both internal and external mechanisms. For a given set-point, the body will act to maintain a temperature (see following). For example, with a fever, attempts to withdraw heat will be resisted until the set-point for that febrile body temperature is reset.

Central Set-Point Temperature regulation is centered in the hypothalamus. The preoptic area of the hypothalamus seems to serve as the thermostatic center for the body.

1 Unless otherwise stated, the general references used in this chapter are Guyton and Hall, 2001 [1] and Schonbaum and Lomax, 1991 [2].

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Peripheral Responses The skin carries sensory receptors to both cold and heat; although, the cold sensors are ten times more numerous. These cutaneous temperature sensors serve as a strong stimulus to shivering and serve to increase or decrease both sweating and vasodilatation. The response of the sensors is dominated by their response to cold.

Summation of Peripheral and Central Sensory Signals The posterior hypothalamus receives signals from both the peripheral temperature sensors and from the preoptic area of the hypothalamus. The signals are integrated and central control signals are sent to the skin to modify sweating, vasodilatation, and piloerection. The dorsomedial portion of the posterior hypothalamus is normally inhibited by the preoptic portion and excited by cutaneous cold sensors. Excitation of this area due to cold leads to stimulation of muscle cells via the lateral columns. This action increases the resting tone of the muscle, which triggers the stretch reflex. The resulting contraction pattern is an oscillation between opposing muscle groups with no purposeful movement.

Increased Body Temperature The body’s temperature increases either from increased heat generation (cellular respiration or shivering), or reductions in skin losses. Increased cellular respiration at rest is possible by two mechanisms: chemical thermogenesis and thyroxine-mediated increases in the metabolic rate. Chemical thermogenesis in adult humans (who lack brown fat) is limited to no more than 10–15% of the basal metabolic energy output. It is the result of the uncoupling of oxidative phosphorylation in response to circulating norepinephrine and epinephrine. In a cold environment, significant increases in thyroxine level and therefore metabolic drive, do occur. However this is a long-term adaptation and is of little consequence in discussing the short-term regulation of body temperature. For the intubated and sedated patient: •

Shivering is pharmacologically damped or lost.

•

Central control, driven by the summation of peripheral and central sensory input, is reduced or lost.

•

Disturbed hypothalamic function can directly reset the temperature setpoint.

Thermal Regulation and Disease States Fever is a response to either endogenous or exogenous pyrogens, or direct effects upon the hypothalamic temperature control centers.

Pyrogens Endogenous pyrogens are families of polypeptides (e.g., interleukin 1) that are produced by macrophages, monocytes, and other white cells. They are mediators of inflammation. They act centrally upon the hypothalamus to modify thermoregulation. The typical fever response shows an initial abrupt rise in core temperature to a peak (acute phase response) with a more gradual decay to normothermia. Endogenous pyrogens do not appear to have other than central effects upon thermoregulation.

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Exogenous pyrogens are polypeptides of origin external to endogenous pyrogens but of similar action.

Cerebral Injury Sustained changes in the thermoregulatory set-point are observed with irritation or compression (tumor) of the hypothalamus. In addition, intra-cerebral release of endogenous pyrogens (cerebral inflammation) can have the same effect. The hypothalamus is exposed to cerebrospinal fluid as well as to blood, so it can be subject to the action of CSF-borne pyrogens [2].

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This Product in its Environment Introduction The first law of thermodynamics can only be applied after defining the system. For our purposes the system consists of three elements: 1. The patient: • Is intubated and sedated. • Is warmer than the environment and therefore will lose heat to the environment. • Will lose more heat to the environment if wet than if dry. 2. The environment. This is typically controlled by air conditioning that is far more powerful than the patient (i.e., it will react to overcome any heat the patient adds to the environment). Within this discussion, outside of the performance of the IVTM System , the single most significant effect upon the patient is the rate of heat loss to the environment. NOTE: When comparing catheter performance, only results obtained from controlled in-vitro methods should be used. Heat exchange to the environment within the clinical setting can be significant and variable depending upon environmental conditions and the degree to which the patient is able to maintain his/her body temperature. 3. There are two heat transfers that occur in the IVTM System: •

Between the fluid in the cold well of the IVTM System and the saline in the coil of the Start-Up Kit.

•

Between the saline in the catheter balloons and the blood of the patient.

The IVTM System responds to both the difference between the patient’s temperature and the set-point and to the rate of change of the patient’s temperature. The system will add or remove heat to maintain the patient at the set-point.

Treatment Algorithms There are four treatment algorithms in RUN: “Max Power”, “Controlled Rate”, "Warming", and “FEVER”.

Max Power (MAX) In this treatment option, the IVTM System seeks to make the patient’s temperature the same as the selected target temperature. It will keep the saline pump operating unless the patient’s temperature “inverts”. This occurs whenever: A. Bath Temperature > Patient Temperature > Target Temperature, OR B. Bath Temperature < Patient Temperature < Target Temperature.

Controlled Rate In this treatment option, the IVTM System will attempt to move the patient’s temperature to the target temperature at the programmed rate of heat exchange (°C

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/hr). When the patient reaches the target temperature, the IVTM System will revert to the MAX treatment option i.e. it will attempt to make the patient’s temperature the same as the selected target temperature.



NOTE: Controlled Rate Controlled rate operates in both warming and cooling modes.

FEVER (FVR) In this treatment option, the IVTM System will starting cooling the patient once the patient temperature is above the target temperature. It does this by keeping the bath at its coldest permissible temperature and then operating the saline pump whenever the patient’s temperature moves above the target temperature. Maximum cooling power is always applied as with Max Power.

WARNING! “Lo” patient temperature alarm limit with “FEVER” The IVTM System will NOT heat the patient when the “FEVER” treatment option has been selected. The “Lo” patient temperature alarm limit ensures that an alarm occurs should the patient stop regulating his/her own body temperature. Such patients will cool to room temperature. This can occur when the patient dies or becomes comatose. INVESTIGATE ALL PATIENT TEMPERATURE ALARMS.

Warming (Warm) In this treatment option, the IVTM System will start warming the patient once the patient temperature is below the target temperature. It does this by keeping the bath at its warmest permissible temperature and then operating the saline pump whenever the patient’s temperature moves below the target temperature. Maximum warming power is always applied as with Max Power.

WARNING! “Hi” patient temperature alarm limit with “Warming” The IVTM System will NOT cool the patient when the “Warming” treatment option has been selected. The “Hi” patient temperature alarm limit ensures that an alarm occurs should the patient become febrile. INVESTIGATE ALL PATIENT TEMPERATURE ALARMS.

The Patient Environment The patient is in equilibrium with his/her environment. The average human generates between 75 and 100 watts of energy. Much of this is spent in simply keeping the body hotter than the environment–heat is lost through convection/conduction to the air and materials that touch the body (sweat facilitates this loss), heat is lost through respiration, and heat is lost via infrared radiation. The rate of heat loss, under normal conditions, is primarily affected by the ratio of the surface area of the patient’s body to his/her weight. Think of the body as a stack of cubes: some on the surface that can lose heat to the environment and others inside that have no direct contact. Only the outside surfaces of the cubes that are the

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surface of the body can lose heat to the environment, yet all the cubes generate heat. The larger the patient, the less surface area there is per unit of volume by which to lose heat. Smaller people heat more quickly for a given energy expenditure and lose heat to a colder environment more quickly than a larger person starting from the same body temperature. When the IVTM System is active, heat is removed from the patient. In a febrile patient, the amount of excess heat is the product of the temperature increase and the thermal mass of the patient, unless the patient has as yet untapped reserves for heat generation. The higher the temperature the patient is allowed to reach prior to starting therapy, the longer it will take to return the patient to a normal temperature. For a given patient, the stronger the endogenous drive to heat production, the longer it will take to cool that patient. Larger patients will take longer to cool than smaller patients because they have more thermal mass. In some cases, the IVTM System may not have sufficient power to reduce the patient’s temperature to normal levels. The use of the IVTM System does not preclude the use of other antipyretic measures. For example, pharmacological agents that can reduce the endogenous drive to increased temperature or any mechanisms for increasing heat loss from the skin will still be of benefit. 1. It is important to use the IVTM System in conjunction with conventional antipyretic measures. 2. Whenever possible, for antipyretic therapy, it is best to precool the IVTM System prior to connection to the patient to optimize performance. This can be done, for example, at the time that the patient is being prepared for insertion of the central line.

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Cool Line Catheter Fever Management – The Standard of Care Fever management has become a standard of care in the neuro-ICU. According to American Heart Association guidelines established for the management of patients with acute ischemic stroke and spontaneous intracerebral hemorrhage, body temperature should be maintained at a normal level [3][4].

Standard Methods of Fever Reduction Standard fever management in the majority of major medical centers in the U.S. consists of antipyretic drug therapy using acetaminophen or ibuprofen, and external/physical cooling. Physical cooling includes surface cooling with water or airfilled cooling blankets, ice packs, nasogastric or rectal lavage, or alcohol baths. Pharmacological agents such as acetaminophen, aspirin, other nonsteroidal antiinflammatory agents, and corticosteroids appear to inhibit the febrile response by inhibiting prostaglandin synthesis, thus interfering with prostaglandin-mediated action on the hypothalamus. In most clinical practices, antipyretic drugs are often prescribed to combat temperatures greater than 38.5°C. External cooling by different methods, such as using rotary fans and sponging the body surface with water, are also used.

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Fever Reduction Clinical Study ®

The CoolGard (Model 2060) was a predecessor to the CoolGard 3000 (Model CoolGard 3000). The CoolGard 3000 has been cleared based upon the data gathered with the CoolGard heat exchange system. The performance of the CoolGard/Cool Line catheter system was studied as part of a clinical investigation, entitled: A Prospective, Randomized, Controlled Multicenter Clinical Study to Evaluate the Safety and Effectiveness of the CoolGard System with Cool Line Catheter in Reducing Fever in Neurointensive Care Unit Patients.

Clinical Study Summary Objective: To study the effectiveness of catheter based heat exchange systems in the reduction of elevated temperatures in critically ill neurological and neurosurgical patients.

Materials and Methods: This study was a prospective randomized, non-blinded trial in which conventional treatment of fever with acetaminophen and water cooling blankets (conventional group) (standardized across centers) was compared to conventional treatment plus a catheter based heat exchange system (ZOLL Circulation, Inc., Sunnyvale, CA) (catheter group). Four patient populations were included in the trial: subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), ischemic infarction (CI) and traumatic brain injury (TBI). To be eligible the patient’s temperature had to exceed o 38 C on 2 occasions or for >4 hours and they had to require central venous access. Temperature was recorded hourly for a minimum of 3 and up to 7 days following randomization. The temperatures were graphed and the area under the fever curve o which exceeded 38.0 C was used as an index of fever burden. The efficacy of the catheter based system was determined by its ability to reduce fever burden in an intention to treat analysis. The safety of the catheter system was also examined.

Results: A total of 296 patients were enrolled over 20 months half of which were randomized to receive conventional fever management and half conventional management and the catheter based heat exchange system. Of the patients 41% had SAH, 24% TBI, 23% ICH and 13% ischemic stroke. The two fever control groups were matched in terms of age, body mass index, gender and overall GCS distribution. Fever burden for the first 72 hours was 7.92 degree hours in the conventional group and 2.87 degree hours in the catheter group demonstrating a 64% reduction in fever burden with the catheter system. There was no increase in infections or the use of sedatives, narcotics or antibiotics in the catheter group.

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The safety of this device has not been demonstrated for fever reduction in patients presenting with subarachnoid hemorrhage or primary traumatic brain injury. The safety and effectiveness of this device was examined in a randomized controlled trial of 296 patients. The mortality results reported in this trial, for the four patient cohorts enrolled, are presented in the table below (CI – cerebral infarction, ICH – intracerebral hemorrhage, PTBI – primary traumatic brain injury, SAH – subarachnoid hemorrhage). Table 2. Mortality by Diagnosis (ITT) Cool Line

Control

n

N

%

n

N

%

p-value*

CI

3

16

18.8

3

14

21.4

0.74

ICH

8

33

24.2

7

27

25.9

1.00

PTBI

10

44

22.7

4

38

10.5

0.24

SAH

13

61

21.3

7

63

11.1

0.15

*Fischer’s exact test

Clinical Study Results in Detail Significant Reduction in Fever Burden The table below, Reduction in Fever Burden, provides the results of the study in terms of its primary end-point for all patients using an intention to treat analysis. There was an highly significant reduction in the fever burden when comparing the use of the IVTM System with the standard methods of fever management. Table 3. Fever Burden – ITT Data Set Log Scale

Natural Scale

Cool Line

Control

Cool Line

Control

N

154

142

154

142

Mean

1.42

2.23

2.87

7.92

95% CI

1.19 – 1.52

2.06 – 2.41

2.27 – 3.58

6.82 – 10.09

p-value

% Reduction

64%

<0.0001 This result was obtained with a significant reduction in the use of topical cooling devices and antipyretic medication use. These results in the following two tables. The two graphs below present the mean temperatures, left justified over the study period, for all patients within the Cool Line and Control cohorts.

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Cool Line Patients (Mean Temperature ± SD) 39 38.5 38 37.5 37 36.5 36 0

20

40

60

Hours

Control Patients (Mean Temperature ± SD) 39 38.5 38 37.5 37 36.5 36 0

20

40

60

Hours

The reduction in fever burden was accompanied by a reduction in the use of adjunctive cooling means as presented in the tables below. Table 4. Use of Topical Cooling Devices Cool Line

Control

% Reduction

p*

One or more topical cooling device (n/N, %)

26 / 154

16.9

67 / 142

47.2

64%

<0.0001

Cooling Blanket use (n/N, %)

25 / 154

16.2

59 / 142

41.6

61%

<0.0001

Other device use (n/N, %)

7 / 154

4.6

19 / 142

13.4

66%

0.008

* Fisher’s exact test

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Physicians' Manual Table 5. Antipyretic Use during Treatment Period Cool Line

Any antipyretic medication use

Control

p*

n/N

%

n/N

%

94 / 154

61.0

127 / 142

89.4

<0.0001

•

Acetaminophen

87 / 154

56.5

124 / 142

87.3

<0.0001

•

Ibuprofen

16 / 154

10.4

29 / 142

20.4

0.02

•

Aspirin

18 / 154

11.7

12 / 142

8.5

0.44

* Fisher’s exact test

Complications The following table lists the number of complications reported, by body system, for all Cool Line and Control cohort patients within the first 30 days. The numbers presented are the total number of reported adverse events by category and then total overall. A patient may have had none, one or many adverse events reported in the course of the study. Table 6. Complications Cool Line

Control

Body as a whole

15

9

Cardiovascular

26

21

GI

21

19

Hematologic

19

14

Infectious

93

74

Metabolic/Endocrine

24

18

Neurologic

49

52

Other

10

9

Peripheral vascular

15

13

Pulmonary

66

51

Renal

7

4

Total

330

275

The following table summarizes the SCVIR Guidelines for expected rates of success and complications and the proposed threshold rates at which some form of retraining or other action is indicated. In terms of complications, the use of the Cool Line is generally associated with complication rates within SCVIR guidelines.

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Table 7. Complication Rates Compared to SCVIR Data Specific Major Complications for Image-guided Central Venous Access SCVIR Expected Complication Rate(%)

SCVIR Proposed Threshold Rate(%)

Subclavian and jugular approaches

Observed Complication Rate (%) in Cool Line/ CoolGard Clinical Trial Cool Line

Control

Pneumothorax

1-2

3

0.9

3.3

Hemothorax

1

2

1.9

0

Hematoma

1

2

0

0

Perforation

0.5-1

2

0

0

Air embolism

1

2

0

0

Wound dehiscence

1

2

0

0

Procedure-induced sepsis

1

2

0

0`

Thrombosis

4

8

3.3

7.8

None of the procedure related adverse events are unexpectedly high. There is no indication that the Cool Line has unacceptable performance as a central line. There were 4 patients in whom a CL-2085B could not be inserted. There were 2 patients for whom a CL-2295A could not be inserted but in whom success was achieved with a CL-2085B. The first pass and overall success rates for CL-2085B are presented in the table below for the three insertion sites, Femoral, Jugular and Subclavian. Insertions were considered a failure if the failure was not due to an operator error (e.g. contamination of first catheter prior to insertion and then successfully implanting the second catheter on its first attempt would be counted as a successful insertion even though two catheters were used). Table 8. Cool Line Catheter Insertion Success n pts

1st Pass Success n,%

Femoral

20

14

70%

20

100%

Jugular

22

19

86%

22

100%

Subclavian

111

107

96%

108

96%

Total

153

140

92%

150

98%

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Specific Use Effects Obvious Fever Upon first presentation of a fever in a patient in a neurologic intensive care unit, standard practice should include the taking of appropriate cultures and antibiotic therapy based upon the result. This practice should be continued when using the IVTM System and Cool Line catheter. Patient Temperature

Bath Temperature

FEVER

COLD

If the IVTM System and Cool Line catheter have been in use for some time, the presence of a fever requires investigation. It is possible for a patient to spike a fever and overcome the capacity of the system. Should this occur at any time the physician should: 1. Confirm that the system is functioning properly. •

Make sure that the system is turned on and is connected.

•

Check the display to make sure that an alarm state has not been deactivated.

•

Confirm that the pin-wheel flow indicator is spinning.

•

Confirm that the patient temperature probe is working. (When standard probes fail they usually do so as an open circuit. This failure mode would be automatically detected and brought to your attention.)

2. Begin the standard regimen for the investigation of fever. In very light patients or in the elderly, fever response may be, respectively, either easily overcome by the system or naturally damped. Regardless of patient temperature or weight, the presence of a cold bath (i.e., minimum bath temperature) should be regarded as the equivalent of a fever and the standard regimen for investigating a fever should be started. If in doubt, turn the IVTM System to standby mode for 1-2 hours and monitor the patient’s temperature. Restart the system as clinically indicated.

Masked Fever vs. Steady State These two states can be difficult to distinguish. If in doubt, put the IVTM System into standby mode and observe the patient’s temperature for 1-2 hours. Restart the system as clinically indicated. With the IVTM System, there is a clear indicator of the activity of the system on the right hand edge of the display. The red/blue meter indicates whether the IVTM System is heating (red) or cooling (blue). In fever response mode, the display will indicate MAX COOLING, this should alert the user to the possibility of another episode of sepsis and standard antisepsis regimens should be followed.

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