TECOTHERM NEO Instructions for Use Revision April 2014

Contents and abbreviations page 1. 1.1 1.2 1.3 2. 3. 4. 5. 6. 6.1 6.2 6.2.1 6.2.2 7. 7.1 7.1.1 7.1.2 7.1.3 7.2 7.3 7.4 7.5 7.6 7.7. 7.8 7.9 7.10 8. 8.1 8.2 8.3 8.4 8.5 8.6 8.7 9. 9.1 9.2 9.3 10. 10.1 10.2 10.3 10.4

Preface ... Intended Use ... Contraindications for Use ... Operators Profile ... Informations for Customers, Service & Technical support ... Short Description of the Equipment ... Symbols, Indications ... Warnings, precaution guidelines ... TECOTHERM NEO operating functions ... The physiologic closed-loop circuit (PCLC) ... Fallback mode ... Plausibility limitations in rectal temperature measurement ... Operations during fallback mode ... TECOTHERM NEO Hypothermia System ... TECOTHERM NEO operating modes ... Complete Treatment Mode (Servo controlled), Treatment profiles . Servo Control Mode (constant rectal temperature) ... Constant Mattress Temperature Mode ... TECOTHERM NEO Hypothermia System Informations ... Indicators and Operation Key elements, Display screen ... External Temperature Probes ... Hoses, Hydraulic lines ... Fill- up set for Filling / Refilling TECOmed thermalizing fluid ... TECOmed thermalizing fluid ... Mattresses, Cool Wraps, parts and protective layers ... MENU and the User Interface ... Display and export of treatment data ... TECOTHERM NEO Hypothermia System Putting into operation ... Initial Set up / Initial Operation ... Pre- operation Check up ... Initial Operation by the customer ... Stop operation / Turn off device ... TECOTHERM NEO System: Filling / Refilling Procedures ... Draining a used mattress ... Application of mattresses to patients ... Hygienic Requirements ... Cleaning and Disinfecting TECOTHERM NEO ... Mattresses, thermally insulated hoses, tubing ... Temperature Probes ... Storage and Transport ... Storage of the TECOTHERM NEO device ... Storage of Mattresses ... Storage of TECOmed ... Transport ...

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11. 11.1 11.2 11.3 11.4 11.5 11.6 12. 13. 13.1 13.2 13.3 13.4 13.5 13.6 14. 15. 16. 17.

Alarm system, malfunctions, incident management ... System Alarm, System failure ... Temperature Alarm ... Flow rate alarm ... Alarm Fluid level low ... Alarm No Mains Power ... Fluid escapes from the TECOTHERM NEO System ... Training & Qualification of personnel ... Service, preventive maintenance, Software Update ... Service & Maintenance ... Cleaning the ventilation hole structure (device bottom) ... Substitution of TECOmed fluid in the device ... Substitution of TECOmed fluid in mattresses and cool wraps ... Check / calibration of temperature probes ... Software Update ... Technical Data, TECOTHERM NEO Specification ... Declaration of Conformity ... Disposal ... EMC guidance for TECOTHERM NEO ...

65 68 70 73 76 79 80 81 81 81 81 82 82 82 83 84 85 85 86

Abbreviations IfU BCT

Instruction for Use Body Core Temperature, as measured via the Rectum using appropriate rectal temperature probes, see 7.4

SF

System Failure

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1.

Preface

1.1

Intended Use

This Instructions for Use (IfU) presents a detailed introduction into the operation modes of TECOTHERM NEO from TEC COM GmbH. The Hypothermia System TECOTHERM NEO is designed for controlled comfortable cold & heat treatment procedures. By means of mattresses or cool wraps cold and heat is applied to the total body, body parts or areas of neonate depending on the therapy objective. One main application is induced hypothermia treatment of neonate affected with Hypoxic Ischemic Encephalopathy. The IfU contains a Technical Desription and technical data. TECOTHERM NEO of TEC COM exhibits SERVO CONTROL operation as a modern excellence feature using MENU assistance. TECOTHERM NEO of TEC COM has been equipped with two micro computers and with numerous monitoring and alarm features which guarantee a high standard of treatment and operation safety. We highly recommend that the operator is familiar with the operation modes and capabilities of the TECOTHERM NEO. Prior to putting into operation carefully read these IfU! This IfU is associated with a software version 062/02.16 or higher. The installed version number is displayed at the lower left part of operator’s MENU display screen after switching on the device. Note: The Manufacturer carries responsibility for basic safety, reliability and capability of the TECOTHERM NEO system only when  local electrical installation fully meets the requirements of the IfU.  initial operation is performed according prescribed Instruction procedure by authorized personnel.  TECOTHERM NEO is operated according to the instructions and statements of said IfU.

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1.2

Contraindications for Use

No general contraindications are known. For possible adverse effects study the relevant treatment and therapy protocols. Avoid direct contact of mattress or cool wrap with patient’s skin! Avoid direct contact of mattress or cool wrap with fresh or non- closed wounds, infectious areas, areas with ulceration and abcesses, rash and burns.

1.3

Operators Profile

TECOTHERM NEO is intended for use by healthcare professionals only. Operating a TECOTHERM NEO requires  Education as Healthcare Professional  Experience in using life support and life sustaining equipment  Experience in using medical electrical equipment  Personnel must be trained in the use of the TECOTHERM NEO before operating the device. We strongly recommend operators to get familiar with the working principles of the TECOTHERM NEO, to develop an understanding of mechanism and procedure of a hypothermia treatment, and to carefully read this Instruction for Use. Note

Operator is requested to carefully check all accepted default or personally set parameters for correctness and adequacy before starting the hypothermia treatment.

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2.

Informations for Customers Service & Technical support

For Technical Support in German please contact: TEC COM GmbH Phone Fax E mail

+49 - 345 - 120 52 04 +49 - 345 – 120 52 11 [email protected]

For Technical Support in English please contact: Inspiration Healthcare Ltd Phone +44 - 1455 840555 Fax +44 - 1455 841464 E mail [email protected]

The manufacturer TEC COM or authorized representives will instruct and introduce the operation personnel prior putting the equipment into operation Additional information, technical support, additional manuals may be requested from the manufacturer and any authorized distribution partner. Manufacturer

TEC COM GmbH Gesellschaft für Technik, Technologie und Vermarktung Am Krümmling 1 D-06184 Kabelsketal Germany

Type label

TECOTHERM NEO Serial Number 2014 / 15 / 01 100-130V / 200-240V 50-60Hz max. 350W Class I / Schutzklasse I IP20 Made in Germany Fuses / Sicherungen: 5x20mm 250VAC 100-130V: S4AH / T4AH 200-240V: S2,5AH / T2,5AH

Manufacturer / Hersteller: TEC COM GmbH Am Krümmling 1 D-06184 Kabelsketal 0494

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3.

Short Description of the Equipment

The Hypothermia System TECOTHERM NEO is designed for controlled cold & heat treatment procedures and application of specific cold and heat doses to neonate and babies. The system applies cold and heat to total body, body parts and areas depending on therapy target by means of mattresses and / or cool wraps NEO PAD. One main application is hypothermia treatment of neonate affected with Hypoxic Ischemic Encephalopathy. Another application designed for controlled hypothermia treatment is Total Body Treatment of Children up to body mass of 50 kg.

TECOTHERM NEO consists of a unique cold & heat generating device, applied parts like mattresses and wrap, interconnecting hoses (tubing set), accessories. Applied parts are connected to the device via hoses by self- sealing quick- disconnect couplings. The patient is provided with cold and heat according therapy target in a fully controlled way by a circulating fluid. This physiologic safe water- based fluid is cooled or warmed in the device and flows through the mattress or wrap continuously supplying the patient with therapeutically prescribed doses.

Patient temperatures are measured with approved calibrated probes connected to the TECOTHERM NEO device. Temperature data is permanently communicated to the device Operational System. Circulation of thermalizing fluid to provide cold and heat, accurately reaching set points and operating at set point temperatures accurately with max. deviation of +/-0,3°C, monitoring the treatment, and alarming when exceeding or falling below temperature limits are performances of TECOTHERM NEO. TECOTHERM NEO is a system with built-in physiologic closed loop circuit PCLC.

TECOTHERM NEO is electronically divided into an Operational System and a Controlling System. Both sub systems are micro computer (µC) based. Both µC communicate permanently to ensure safe and proper operation according to therapy needs. A comfortable user MENU will guide the operator to the treatment modes, advise how to proceed the treatment and how to manage treatment details. Menu language may be preselected using Sub – Menu “Language”: English, Deutsch, Espanol …. .

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TECOTHERM NEO offers three separate treatment modes to induce hypothermia and to re- warm the patients. TECOTHERM NEO uses 2 independent temperature probes:  

rectal probe for measuring Body Core Temperature (BCT), mandatory required for SERVO mode. skin probe for measuring skin abdominal or forehead temperature etc, optional.

The three treatment modes are I

SERVO CONTROL Programmable Complete Treatment Mode

II SERVO CONTROL Constant Rectal Temperature Mode III Constant Mattress Temperature Mode

The Operator selects the treatment mode I, II or III and treatment parameters for inducing hypothermia, normothermia or hyperthermia following the MENU instructions. Attention: Temperature probes must be properly placed before treatment procedure can start. Attention Treatment and selection of treatment procedure is fully within the responsibility of the therapist, physician or trained qualified medical personnel. Attention For neonate and other patient hypersensitivity or restricted compatibility to hypothermia and / or hyperthermia is in general not known. Neonate receiving such treatment must be under careful observation.

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4.

Symbols, Indications

Important Information

Attention, Caution, Warning

Electrical Hazard !

Do not touch contacts!

Applied Part Type BF

Consult Instruction for Use

Rectal Temperature Sensor socket

R

Skin Temperature Sensor socket

S

Key “Turn On”

System failure

SF

Temperature Alarm

Alarm No or restricted Flow

Alarm Low fluid level

Symbol AUDIO paused

No Mains Power (separate LED indicator)

Internal System Failure (separate LED indicator)

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5.

Warnings, Precaution guidelines

Warnings 

Modification of the TECOTHERM NEO not authorized by the manufacturer is not allowed.



Do not open the device! Risk of electrical shock. Opening the device is restricted to service and other authorized personnel.



Do not remove cover part. Risk of electrical shock when touching inner parts and components.



The TECOTHERM NEO device must be plugged to the mains only to shockproof sockets. Mains voltage must be 100-130V or 200-240V with 50-60 Hz. Use only cord supplied with the device or a medical grade approved equivalent cord not longer than 2,5 m.



Caution During operation and treatment: The operator must not simultaneously touch the patient and metallic device parts (plug / connector sockets, grounded connected parts at the device rear, contacts of fuse compartment).



Both temperature probe sockets on the front of device and the USB socket on the rear are marked with ESD warning symbols. They are sensitive against discharge of static electricity, their electrical contacts should not be touched with the fingers or tooling. When connecting probes or USB stick to their sockets the following precautionary procedure is required: Before plugging, touch the fan protective grid at the rear with your other hand. It is recommended that all staff involved in using TECOTHERM NEO receive an explanation of the ESD warning symbol and training in ESD precautionary procedures. That training should include, in addition to the precautionary procedure prescribed above, general information on the origin, the possible impact and the prevention of electrostatic charging.



Repair and maintenance are restricted to authorised personnel only!



For a reliable and safe operation use only original components, applied parts and spare parts supplied or recommended by the manufacturer.



Substitution of original parts or components of the TECOTHERM NEO system by parts or components which are not licensed by the manufacturer is likely to put the system and the patient at risk!



Only TECOmed (or approved substitute ) should be used as circulating fluid. Otherwise it would be likely to put the system and the patient at risk!

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

Use only temperature probes in accordance with IfU and with the technical specification of the manufacturer. Applying different probes may lead to incorrect and wrong temperature data. This is likely to put patients at significant risk!



Ensure that probes are properly connected to the TECOTHERM NEO socket marked "R" (Rectal for Body Core Temperature) and “S” (Skin for Surface Temperature).



Ensure that Rectal and Skin Temperature Probes are correctly placed in / on the patient and that probes are properly secured.



Do not use TECOTHERM NEO with or in presence of flammable agents.

Safety, Reliability Caution For a reliable and safe operation of the TECOTHERM NEO use only original components, parts and spare parts and accessories supplied or licensed by the manufacturer. Use only such components, parts and accessories for hypothermia treatment with a TECOTHERM NEO system! Warning

Substitution of original parts or components of the TECOTHERM NEO system by parts or components which are not licensed by the manufacturer is likely to put the system and the patient at risk!

Precautions Consider within Intended Use Note: Therapeutic Induced Total Body Hypothermia is a systemic treatment method. Select target temperatures cautiously. Re- warming: Select low re- warming rates to smoothly reach normal BCT of 37°C. Patient body mass may severely influence re- warming. The larger the mass the slower the re- warming.

Futher notes When TECOTHERM NEO is run in the Constant Mattress Temperature Mode to lower body core temperature an independent temperature measurement is required to monitor hypothermia.

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Note that in this mode applied treatment temperature and duration do not allow a realistic estimation of the actual degree of lowering of patient’s BCT.  Medical electrical equipment needs special precautions regarding Electromagnetic Compatibility and needs to be installed and put into service according to the Electromagnetic Compatibility information provided below in 17. EMC guidance.  Portable and mobile RF communication equipment can affect medical electrical equipment. Observe the recommended separation distances listed below in 17. EMC guidance.  The TECOTHERM NEO device should be subject to regular maintenance and service, see section 13.  Refill TECOmed fluid regularly every 3 months, see section 8.5.  Note Circulation may stop, fluid flow stops. In such cases mattresses may cool neonate or patient slowly down. Especially during treatment re-warming phase neonate may suffer from extraction of body heat back into the mattress. Change such condition soon!  Replace TECOmed fluid regularly every 3 months, see section 8.5. / 13.3.  Only TECOmed (or approved substitute ) should be used.  The operator or the user should not apply other cleaning, disinfecting and decontamination procedures than those recommended by the manufacturer. If in doubt contact your local representative.

Precaution Notes for placement Location  The TECOTHERM NEO device should not be used adjacent to or stacked with other equipment. If adjacent or stacked use is necessary, the TECOTHERM NEO should be observed to verify normal operation in the configuration in which it will be used.  The unit must be placed in such a way that it could be easily disconnected from mains power. Removing the mains plug must be always possible.  The unit must be placed horizontally onto a plane support  The system is fan cooled. Sufficient space must be allocated so that a free flow of air from all sides can reach the bottom of the device when it is in operation.  Device should be located so that there is a distance of at least 15cm between rear side and a wall or another limiting surface to ensure free outflow of the cooling air.  Do not place the device into small cabinet compartment or onto small scale boards. Do not cover the device!  The unit should be placed avoiding air to be blown towards the patient.  The unit should be placed so that optical blink alarms are clearly seen and acoustic alarms are clearly audible. IfU TECOTHERM NEO TN300 EN-15.docx

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 Do not place mattresses and hoses onto hot or warm supports during operation  Do not place the device during operation near intensive heat sources.

Attention Ensure and leave enough space around the TECOTHERM NEO not to obstruct passage of acting personnel. Ensure that hoses, cable cord, temperature probes etc. do not form obstacles.  Ensure that placement of TECOTHERM NEO is not forming trapping zones for hands and fingers to avoid contusions and other injuries.  Check type of mattress and interlayer. Use thin disposable interlayer which must at least fully cover the mattress with some border. Such interlayer must be coated at lower side with plastic coating to prevent penetration of blood, liquids or liquid media onto the upper surface of the mattress and to protect the patient.  Note: Place mattress/ cool wrap onto a  10 - 20 mm thick foam material that has good thermal insulation during operation.

Using an incubator When using an incubator to perform hypothermia treatment:  Pay attention that there is enough space to properly place mattress or cool wrap. Otherwise kinking of hose set and / or tubing near mattress and mattress folding may cause restricted fluid flow, bad circulation or even flow blocking  Place the hoses set in a way that the hoses are in a straight line. Fasten the hoses in such a way to avoid kinking of the tubing near the mattress  Note: Place mattress onto a  10 - 20 mm thick foam material that has good thermal insulation during operation.

Note: Do not put mattress directly onto compact silicon inlays used in incubators.

Attention Ensure that incubator heaters are shut off! Ensure that there is no forced air circulation. It may cool down the neonate in a re- warming phase of the treatment.

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Indications for hazardous substances TECOTHERM NEO does not contain parts or substances stemming from derivatives of blood or human / animal tissues. TECOTHERM NEO does not contain parts made of Latex or its derivatives. TECOTHERM NEO Applied Parts do not contain parts made of PVC with DEHP softener / plasticizer Thermalizing Fluid TECOmed is made of 70 % water, 30% pure Ethyl alcohol. Very small quantity < 0,3 % denaturing agent Methyl- Ethyl- Ketone MEK is added. Details see Safety Data Sheet.  Caution

Do not swallow or ingest fluid.

 Skin contact with TECOmed fluid is harmless.  Note

After use close TECOmed containers tightly.

Ambient Conditions To ensure a proper operation in normal use pay attention to the following conditions  Protection The device should be protected from dampness and wetness (e.g. splash water.) 

Do not operate device in rooms where flammable mixtures of anaesthesia gases with oxygen, laughing gas N2O or air may evolve.

 To have full cooling power ambient temperature should not exceed 27°C. Otherwise the TECOTHERM NEO system may not achieve the lowest possible set temperature if using a large mattress.  Relative Humidity during treatment within a range of 30 % - 80 %  Ensure that during treatment / operation no installations, systems, devices and the like are operating or are intended to operate next to TECOTHERM NEO and producing ultraviolet radiation intense infrared radiation strong electromagnetic radiation mechanical shocks, vibrations.

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6.

TECOTHERM NEO operating functions

Operators should familiarise themselves with the operating instructions. It is of crucial importance that they are fully familiar with the actions to be taken in the case of alarms and initial operating errors occurring during use. Operators should furthermore develop an understanding of the TECOTHERM NEO as a system, comprising of a physiologic closed-loop circuit (PCLC).

6.1

The physiologic closed-loop circuit (PCLC)

In accordance with specified applications (see 1.1) TECOTHERM NEO is used to regulate rectal measured body core temperature of patients, which is a physiologic variable, in a specific way or to maintain it at a constant level. Following an as rapid as possible cooling down to 33.5°C this temperature is subsequently to be maintained over a 72 hour period, followed by a gradual steady re-warming up to 37°C within a period of 7 hours or longer. This is achieved by placing the patient into effective thermal contact with a coolant fluid perfusion mattress (see 8.7). The temperature of the fluid determines the changes which will take place in the patient’s core body temperature: if it is lower than that of the patient, the patient’s temperature will fall – if it is higher the patient’s temperature will rise. The greater the difference in temperature between patient and the fluid the faster the change in the patient’s core body temperature, whereby a change of 0.5°C / hour should already be considered being rather “rapid”. The mattress temperature (i.e. the average temperature of the fluid) must obviously be maintained within certain limits in order to prevent possible damage to tissue (frostbite, burns). These limits are set at 12°C and 39°C respectively, whereby temperatures around 12°C are needed only during the initial treatment phase to allow for an as rapid as possible cooling down process; subsequently these temperature levels will no longer be required. In order to achieve the intended progression in the patient’s core body temperature the mattress must be kept at the correct temperature level, at all times. The right temperature will depend on a number of factors: what is the current stage of treatment; what are the (changing) ambient conditions, environmental factors; how effective is the thermal contact between mattress and the patient; how intensive or reduced is the patient’s own level of thermal output. First of all, sufficient information concerning the patient’s current core body temperature must be available in order to determine the correct mattress temperature required. However, the impact of external factors is often rather complex and difficult to assess, so that manual setting of the mattress temperature by the operator will often result in more or less wide fluctuations of the core temperature around the target level, especially as the actual results of a temperature adjustment do rarely become apparent within less than a half-hour period. This also does lead to increased nursing requirements, since repeated adjustments in temperature will become necessary.

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The operator is spared these complex considerations and corresponding decisionmaking process by the automatic temperature control system performing these tasks in the two automatic operating modes. The operator now merely needs to schedule the overall intended progression of change in the patient’s core body temperature in advance, using a limited number of parameters, which can be intuitively understood. The temperature control system using the rectal temperature measurements subsequently calculates the exact mattress temperature required, on a continuous basis, in order to stay within the set schedule. The TECOTHERM NEO temperature control module ensures that the mattress delivers the temperature required based on these calculations, as fast as possible. Like any other temperature control system TECOTHERM NEO comprises a closed-loop control circuit. Any deviation from target settings is counteracted immediately. Assuming that the rectal temperature measurement is 0.1° higher than it should be, at any given point in time, the control system would lower the mattress temperature by 1° if the internally programmed amplification factor had a value of 10. With a certain delay this lowering of mattress temperature will result in a corresponding decrease in rectal temperature and the subsequent gradual convergence back towards the target value. As a result the decrease in mattress temperature will in turn be reduced. Thus the cycle is closed and since the regulated rectal temperature is a physiologic variable of measurement this represents a physiologic closed-loop circuit (PCLC). During the initial stages of treatment, i.e. rapid cooling down of the patient, an inevitable overshoot will occur – actual values will in fact fall somewhat short of the target value of 33.5°C. Standard parameters have been chosen to reduce such overshoot to below 0.5°. A stable status is subsequently reached within a settling time of approx. 1 hour; there are no remaining deviations from set parameters. During this constant phase, which usually lasts about 72 hours, potential fluctuations will be less than 0.3°. Following commencement of the re-warming phase there will initially be a rise in mattress temperature. Only after a response period of approx. 30 minutes will there be any noticeable change in rectal temperature. This will subsequently increase only gradually as well and therefore initially lag marginally behind the intended progression. This tracking error is gradually reduced and will in any event always remain below 0.5°. This physiologic closed-loop circuit can obviously operate properly only if all elements of this functional chain do perform their designated tasks as intended. Assuming normal operations of the TECOTHERM NEO unit a number of additional requirements need to be met:  The temperature regulating fluid must circulate at a flow rate sufficiently high to ensure an efficient thermal transfer to or away from the patient. This process is monitored by the unit and, if required, the operator will be alerted to initiate appropriate corrective measures.  There must be sufficient thermal contact between the coolant fluid perfusion mattress and the patient, as any change in mattress temperature may otherwise have no or only limited effect on rectal temperature. It is of crucial importance for the operator to position the mattress correctly and in accordance with the operating instructions (see

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8.7). The equipment can detect any fault in this respect only after lapse of the response period of approx. 30 minutes, at the earliest, if despite constant adjustment of mattress temperature the expected reaction in rectal temperature does not occur and the rectal temperature eventually moves outside the permissible range of +/- 0.5° around the target value. Only at that point in time will a temperature alarm be activated.  Rectal temperature, as the measurement ultimately to be regulated, must be

recorded accurately. Incorrect measurements taken over an extended period of time, regardless of cause, would immediately result in an unwanted change in the patient’s actual core body temperature. Example: An incorrectly placed rectal probe (e.g. slipped out) will record a temperature lower than the actual core body temperature, since the rectal probe will now measure the air temperature in proximity of the rectum. The current temperature measurement is shown on the display. This temperature will in fact be lower than the rectal target temperature of 33.5°C. Consequently there is now a deviation in temperature (cause). This will immediately result in an increase in mattress temperature (effect), since the unit’s control system will work to again increase the core body temperature, which is now perceived being too low. Upon activation of the alarm, at least, the operator can conclude from the low rectal temperature recording shown on the display that the rectal probe may have slipped out and will need to check this immediately.

6.2

Fallback mode

Amongst various possible causes which may lead to a malfunctioning of the physiologic closed-loop circuit the systematically false recording of rectal temperature would be the most disadvantageous, especially if it went unnoticed for an extended period of time. Only this kind of false measurement would lead directly to the wrong core body temperature for the patient. Such false readings can have a number of different causes: 

incorrect placement of the rectal probe, e.g. slipped out



excessively high levels of electromagnetic interference from the environment



deficiencies in contact(s) at plug connections



defective rectal probe.

Unfortunately it is not possible to permanently monitor the rectal probe with the aid of a second control probe, as the insertion of 2 rectal probes would be impossible in the case of an infant. The otherwise recommended control by means of an additional skin probe is not sufficiently accurate and too exposed to potential external impact for such readings to be used in arriving at an informed decision. For these reasons measuring results taken from the rectal probe are checked as to plausibility, whereby it will depend upon the relevant stage of treatment as to what range of values for rectal temperature recordings will be classified as being plausible and therefore acceptable. In the case of measurements occurring systematically outside this specified range of acceptance

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TECOTHERM NEO will stop operating as a physiologic closed-loop circuit and instead switch into fallback mode. The operator will be alerted and informed about the current status and subsequently needs to decide upon an appropriate course of action. Depending upon the stage of treatment a choice of suitable options will be given for the unit to immediately resume operations. The operator can now follow these prompts or make changes according to his own assessment of what actions may be required. The key characteristic of the fallback mode is, that the required mattress temperature will no be longer calculated by the temperature control system, but that it now needs to be specified by the operator. In order to be able to take an informed decision under these circumstances the operator immediately needs to arrange for alternative methods of continuing a reliable recording of the patient’s rectal temperature, completely independent from the TECOTHERM NEO system. Although it will generally be possible to continue the current treatment process up to the end entirely in fallback mode, one should always try to identify and eliminate the actual cause of any false measurement. If no obvious reasons can be detected a replacement of the rectal probe is recommended. As soon as acceptable measurements are available again the unit will switch back automatically into the physiologic closed-loop circuit operating mode and the operator will be advised accordingly. Only in rare cases is it possible, that measurements may again be correct but still marginally remain outside the valid range of acceptance. If the operator can see that the measurements are indeed correct and there is still no automatic reversal, then this reversal can be prompted through use of the “Servo” button.

6.2.1 Plausibility limitations in rectal temperature measurement In accordance with the designated applications for the TECOTHERM NEO system (see 1.1) it would be possible in the extreme case for the rectal temperature of a “patient” (not necessarily an infant!) to vary between 30°C and 38°C, at the beginning of the treatment cycle. Initial temperature recordings between 29°C and 39°C are consequently categorised as plausible readings. In the case of measurements outside this range the control system cannot be started and activation will be denied, with corresponding notification. This comparatively broad range of tolerances, however, does not entail any untenable elements of risk. On the one hand it can be assumed, that intensive care and monitoring of the process is safeguarded during the initial stages of treatment, when the rapid achievement of stable conditions is the primary objective. The range of acceptable tolerances on the other hand is rapidly reduced following the initial stages of treatment until a status of stable condition has been reached. From that point forward the acceptable range of tolerances will be merely 1° above or below the corresponding set target value. In the event of adjustments being made to the relevant target values the

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corresponding threshold values will change accordingly, e.g. they will rise during the rewarming phase at the same speed as the rectal temperature target value. Besides the monitoring of compliance with these absolute tolerance thresholds rectal temperature measurements are also checked as to their speed of change. The threshold value in this respect is 0.3°/minute. Any changes faster than this, as in the case of the probe having slipped-out, will be read and evaluated as non-plausible and will trigger the switch to fallback mode.

6.2.2 Operations during fallback mode As soon as the fallback mode has been activated, due to an infringement of tolerance thresholds, the operator must intervene and determine how the mattress temperature is to react from that point on forward. In this context it very much depends on the current stage of treatment in deciding on how best to proceed in an expedient manner. Correspondingly parameters are set for immediate activation of the fallback mode which will, at least initially, not result in any additional exposure to risks. The operator will need to adjust these parameters to prevailing conditions. With the aid of the graphic display the operator can obtain a good indication from the diagram of the progression of mattress temperature up to that point. Only once these steps have been taken is it advisable to commence with any trouble-shooting efforts or even a replacement of the rectal probe, in order to restore automatic operations as quickly as possible. Depending on the current stage of treatment two essentially different types of parameters and optional settings are available for operations in fallback mode. If the rectal temperature is to be either kept constant or to be adjusted to a specific value as quickly as possible, then the mattress temperature will be used as an immediate control parameter which can be reset, if required, at any time. During the initial phase of rapid cooling down to e.g. 33.5°C the pre-defined setting for fallback mode will be a mattress temperature of 20°C. This will initially ensure that the cooling down process, once initiated, will be continued. Depending on how far the cooling down process has progressed up to this point, the temperature level of 20°C may still be too high or otherwise already too low. This needs to be assessed by the operator on the basis of an independent measurement of the patient’s actual rectal temperature and the temperature will subsequently need to be adjusted accordingly. As soon as the (independently measured) rectal temperature does approach the target value of 33.5 °C additional adjustments to mattress temperature will become necessary, in order to stabilise the temperature at 33.5°C and to prevent any further cooling down of the patient. In phases during which the rectal temperature is to be kept constant, e.g. at 33.5°C or finally at 37°C, the pre-setting for the mattress temperature will be the same as that for the rectal temperature to be maintained at a constant level. Depending on ambient

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conditions as well as the patient this may be marginally too high or somewhat too low. The progression of mattress temperature up to that point, as shown in the diagram, will provide useful guidance in this respect for corrective measures to be taken. If the fallback mode continues to hold any longer, the operator will again have to assess, on the basis of independently taken readings of the patient’s rectal temperature, whether the choice of mattress temperature has been correct. Different criteria do apply during treatment phases when the rectal temperature is to be gradually adjusted at a pre-determined speed. It is known that in this case the mattress temperature will gradually change, at the same speed, albeit with a certain delay with regard to the pre-determined rectal temperature. A correspondingly accurate automatic re-warming can schematically be illustrated as follows: 40

35

30

Rectal set temperature Rectal measured temperature Mattress temperature

time

25

In practice, however, the mattress temperature will not always need to be exactly 1° above the rectal temperature and depending on the patient it may be even higher, as well as lower, than the rectal temperature. Certain fluctuations may also be due to interference, as indicated in the left segment of the diagram.

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