Clinical Guidelines (Nursing)

Temperature Management

  • Note: This guideline is currently under review. 

    Introduction

    Aim

    Definition of Terms

    Assessment

    Management

    Companion Documents

    Links

    References

    Evidence Table

     

    Introduction

    Temperature management is a significant area of clinical practice particularly within paediatric nursing. Maintaining a constant body temperature is important and especially so in the neonatal population. Hypothermia and hyperthermia should be avoided as they can have severe adverse outcomes, increasing morbidity and mortality. Maintaining correct body temperature maximizes metabolic efficiency, decreases oxygen use, protects enzyme function and to decrease caloric expenditure.

     

    Aim

    To provide health care staff with information that enables them to manage temperature management in patients at the Royal Children’s Hospital.

    Definition of Terms

    Thermoregulation: The ability to balance heat production and heat loss in order to maintain body temperature within a certain “normal” range.

    Neutral thermal environment (NTE): narrow range of environmental temperature in which a person is able to maintain a neutral thermal temperature. A neutral thermal temperature is the body temperature at which an individual’s oxygen and energy consumption is minimised.

    Fever:

    • pertaining to or marked by a fever
    • is caused by a change in the body’s temperature set point, usually caused by infection

    Temperature 37.2 – 38.0°C -
    Temperature > 38.0° C-
    Hypothermia: Body’s core temperature drops below that required for normal metabolism and body functions Neonate- a temperature <36.5 ºC
    Infant/child- a temperature <36 ºC
    Link to Onc – febrile neutropaenia CPG

    Hyperthermia: Is an elevated body temperature due to failed thermoregulation that occurs when the body produces or absorbs more heat than it can dissipate. Hyperthermia differs from fever in the mechanism that causes the elevated body temperature.
    Mild hyperthermia -a temperature>37.5 ºC
    Extreme hyperthermia – a temperature > 38.8 ºC
    Link to fever in the Peadiatric patient CPG

     
    Heat Stroke: thermoregulation is overwhelmed by a combination of excessive metabolic production of heat (exertion), excessive environmental heat and insufficient or impaired heat loss. This results in an abnormally high body temperature

     
    Neonate: an infant that is up to 28 days corrected post term (e.g. an infant born at 34 weeks gestation and is 8 weeks old is 14 days corrected post term).

     
    Non shivering thermogenesis: The primary source of heat production in the neonate. It is the production of heat by metabolism of brown fat Brown fat (deposited after 28 weeks gestation principally around the scapulae, kidneys, adrenals, neck and axilla) is a thermogenic organ unique neonates

    Methods of heat loss:

    1. Conduction: Transfer of heat from one solid object to another solid object in direct contact with it
    2. Convection:Transfer of heat from the body surface to the surrounding air via air current
    3. Radiation:Transfer of heat to cooler solid objects not in direct contact with the body
    4. Evaporation: Heat loss occurring during conversion of liquid to vapour

     

    Radiant warmer:

    Radiant warming cots are designed to provide thermal stability to infants while allowing direct observation. These cots can be operated in servo control mode (the heating elements turn on and off according to measured changes in the infant’s skin temperature) or manual control (the heater is set to a constant power level).

    Isolette: The trademark name for an autonomous incubator unit that provides a controlled heat, humidity and oxygen microenvironment for the isolation and care of premature and low birth weight neonates, and infants. The device is made of a clear plastic material and has a large door and smaller portholes for easy access to the infant with a minimum of heat and oxygen loss. A servo control mechanism can be used to constantly monitor the infant’s temperature and control the heat within the unit.

    Assessment

    At risk groups:

    • Neonates, especially if premature or small for gestational age
    • Burns patients
    • Trauma patients
    • Theatre patients

    Physical Assessment:

    Temperature should be measured on admission and as per care plan (3-4 hourly for neonates) unless the temperature falls outside the normal limits- then it should be measured hourly till back within normal limits (link to Febrile Child CPG)

    Method of taking temperature:

    • Neonate -to 3 months age- rectal or axilla temperature using digital thermometer
    • > 3 months age- tympanic temperature

     (Refer to manufacturer’s instructions for correct use of thermometers)


    Temperature may also be monitored in specialty areas e.g theatre, PICU, by the following methods

    • Oesphageal
    • Skin
    • nasopharyngeal

    Management

    If using a radiant warmer, ensure the following:

    • Radiant warmer should not be used in manual mode for ongoing clinical care
    • Radiant warmer is set to servo control to prevent over-heating
    • Over-heating of the neonate is a risk if the skin probe is not appropriately sited, or the radiant warmer is left in manual mode
    • Skin probe must be placed on the neonate’s abdomen, and sited away from bony prominences and areas of brown fat
    • Do not put the skin probe under the neonate due to risk of pressure injury and risk of measurement of a false high temperature
    • Set skin probe to 36.5 - 36.8

    If using an incubator, refer to Thermoregulation in the Preterm Infant guideline or Isolette use in Paediatric Wards RCH procedure.

    For peri-operative management refer to peri-operative services

    If hypothermic

    Neonate:

    • Notify doctor
    • Assess environment and what clothing baby wearing
    • Correct any environmental factors e.g. remove from draughts
    • Add layer of clothing and extra blanket if needed (within SIDS guidelines)
    • Maximum layers for neonate- singlet, grow suit, hat (if on continuous monitoring), socks/booties, one wrap and one blanket
    • Re-measure neonate’s temperature half to one hour after each intervention
    • If temperature is still <36.5ºC with the above layers, into Isolette (refer to use of Isolette on Ward procedure/policy)
    • For prolonged procedures place neonate on radiant warmer (on low manual heat setting), consider using other warming devices as indicated by condition. Observe for signs of complications (see below)

    Infant/child:

    • Notify doctor
    • Assess environment and what clothing is being worn
    • Add extra layer of clothing or blanket as required
    • Use warming devices as necessary during procedures and post-operatively
    • Observe for signs of complications

    If Hyperthermic

    • Notify Doctor
    • Assess environmental factors and what clothing is being worn. Check and alter NTE if required
    • Correct environmental factors if relevant
    • Ensure patient appropriately dressed for environment, remove layer of clothing or blankets as necessary
    • If temperature remains high despite appropriate environmental temperature, consider other causes i.e. sepsis Link to Sepsis CPG

    If Febrile

    • If temperature 37.5 – 38.0° C- observe patient for signs of infection, notify doctor, take temperature hourly till back within normal range (link to Sepsis CPG)
    • Neonate: If temperature >38ºC - notify doctor, take temperature hourly till back within normal range, prepare for septic workup if ordered by Doctor
    • Infant/Child: report temperatures > 38.5°C in patients > 3 months of age, consider medical review (link to Febrile Child CPG, Oncology- febrile neutropaenia CPG)
    • Refer to each department for management of febrile infants/children specific to that department

    Potential Complications

    Cold stress


    The neonate’s initial response to a cold environment is to constrict superficial blood vessels to minimize transfer of heat from the core to the surface of the body. Superficial vasoconstriction causes the mottled appearance of the skin. If the neonate is not warmed then cold stress can occur.
    Cold stress may result in:

    • Increased metabolic rate, leading to increased oxygen consumption
    • Increased caloric consumption and decreased glycogen stores which can lead to hypoglycaemia
    • Development of acidosis due to pulmonary vasoconstriction
    • Thermal shock and disseminated intravascular coagulation, progressing to death

     

    Hypothermia

    May result in:

    Mild (32-36ºC)

    • Constant shivering
    • Tiredness
    • Low energy
    • Cold or pale skin
    • Tachypnoea
    • Feed intolerance
    Moderate (28-32ºC)
    • Confusion, unable to think or pay attention
    • Loss of judgement/reasoning
    • Loss of coordination
    • Drowsiness
    • Slurred speech
    • Slow, shallow breathing
    Severe (>28ºC)
    • Unconsciousness
    • Shallow breathing/apnoea
    • Weak, irregular pulse
    • Dilated pupils

    Hyperthermia

    May result in:

    • Vasodilatation
    • Increased metabolic rate
    • Increased fluid loss/dehydration
    • Poor feeding
    • Nausea and Vomiting
    • Headaches
    • Decreased Blood Pressure
    • Fainting/dizziness

    Heat Stroke

    May result in:

    • Confusion
    • Hostile behaviour
    • Appearance of being intoxicated
    • Tachycardia
    • Tachypnoea
    • Decreased blood pressure
    • Seizures

     

    Companion Documents

     

    Links

    Product information


    References

    1. Block, J., Lilienthal, M., Cullen, L., White, A. (2012). Evidence-Based Thermoregulation for Adult Trauma Patients. Critical Care Nursing Quarterly, 35 (1): 50-63
    2. Ellis, J. (2005). Neonatal Hypothermia. Journal of Neonatal Nursing, 11: 76-82
    3. Macario, A., Dexter, F. (2002). What are the Most Important risk Factors for a Patient’s Developing Intraoperative Hypothermia? Anesthesia & Analgesia, 94 (1): 215-220
    4. Walter, F.A. (2013). Heat-Related Illness. Emergency Medicine Clinics of North America, 31 (4): 1097-1108
    5. Wing, R., Dor, M.R., McQuilkin, P.A. (2013). Emergency Medicine Clinics of North America, 31 (4): 1073-1096
    6. Clinical Skills. Thermoregulation: Delivery Room Care, Radiant Warmers, and Double Walled Incubators (Neonatal). Retrieved from https://evolve.elsevier.com; Nursing Skills. Date retrieved 3/4/2017.

     

    Evidence Table

    Please click here to view the evidence table.

     

     

     

    Please remember to read the disclaimer

     

    The development of this nursing guideline was coordinated by Trudy Holton, Clinical Nurse Educator, Butterfly Ward, and approved by the Nursing Clinical Effectiveness Committee. Updated September 2014.