Therapeutic Hypothermia for infants > 35 wks with moderate or severe Hypoxic Ischaemic Encephalopathy (HIE) Clinical Guideline Reference Number:

Transcription

1 This is an official Northern Trust policy and should not be edited in any way Therapeutic Hypothermia for infants > 35 wks with moderate or severe Hypoxic Ischaemic Encephalopathy (HIE) Clinical Guideline Reference Number: NHSCT/10/285 Target audience: Sources of advice in relation to this document: Dr Hugo Lambrechts, Associate Specialist, Neonatal Unit Dr Sanjeev Bali, Consultant Neonatologist Mrs Sandra Rankin, Ward Manager, Neonatal Unit Replaces (if appropriate): N/A Type of Document: Directorate Specific Approved by: Policy, Standards and Guidelines Committee Date Approved: 27 January 2010 Date Issued by Policy Unit: 5 May 2010 NHSCT Mission Statement To provide for all the quality of services we would expect for our families and ourselves 1

2 Therapeutic Hypothermia for infants > 35 wks with moderate or severe Hypoxic Ischaemic Encephalopathy (HIE) Clinical Guideline January

3 Therapeutic Hypothermia for infants > 35 wks with moderate or severe Hypoxic Ischaemic Encephalopathy (HIE) Clinical Guideline Background The recently updated Cochrane Library systematic review Cooling for newborns with hypoxic ischaemic encephalopathy (HIE) 1 included eight randomised controlled trials, comprising 638 term infants with moderate or severe encephalopathy and evidence of intrapartum asphyxia. Therapeutic hypothermia (cooling) resulted in statistically significant reductions in: 1. Mortality NNT Neurodevelopmental disability in survivors NNT 8 This gave a relative risk reduction of 24%, absolute risk reduction of 15% and Number Needed to Treat (NNT) of 7. Adverse effects of hypothermia included sinus bradycardia, a borderline increase in the need for inotrope support and a significant increase in the incidence of thrombocytopaenia (platelet count below 150 x 10 9 /L). There was no significant increase in major adverse effects from cooling in trials included in this systematic review or in the interim analyses of infants recruited to the Infant Cooling Evaluation (ICE) trial, an international multicentre study based in Australia (this trial was stopped because interim analysis showed a significant benefit of cooling, thereby clinical equipoise was lost) Conclusion: Therapeutic hypothermia is beneficial to term newborns with HIE. Cooling reduces mortality without increasing major disability in survivors. The benefits of cooling on survival and neurodevelopment outweigh the short-term adverse effects. Objective To treat near-term infants with moderate or severe HIE with whole body therapeutic hypothermia using a composite protocol drawn from the TOBY study and ICE trial. Criteria for starting Therapeutic Hypothermia - Consider 1 to 4 below 1. Gestational age > 35 weeks 2. Less than 6 hours of age 3. Moderate or severe HIE - Several clinical criteria in either category (Sarnat and Sarnat staging): Moderate HIE Severe HIE Consciousness Lethargic Comatose/ obtund Activity Decreased Absent Posture Distal flexion Decerebrate (complete extension) Tone Hypotonic Flaccid Primitive reflexes Weak suck, gag & Moro Absent suck, gag & Moro Pupils Constricted Deviated, dilated, non-reactive Heart rate Bradycardia Variable Respiration Periodic Apnoeic 4. Evidence of peripartum hypoxia/ ischaemia - at least 2 of: o Apgar score of 5 or less at 10 minutes o Mechanical ventilation (bag/ neopuff with mask or ETT) or need for resuscitation at 10 minutes o Cord ph < 7.0 or, blood gas ph < 7.0 or base deficit > 12 within 1 hour of birth 3

4 Reasons for not starting Therapeutic Hypothermia Inability to commence Therapeutic Hypothermia within 6 hours of birth Birth weight < 2 kg Major congenital abnormalities Severe clinical coagulopathy Death appears inevitable When to initiate Therapeutic Hypothermia Inborn infants - Antrim Hospital Cooling should be initiated for infants meeting the Therapeutic Hypothermia criteria as outlined. Passive cooling should commence as soon as a decision is made for Cooling until the equipment is set up. If no bed is available in Antrim, contact the Regional Neonatal Unit RJMH, Belfast for urgent transfer for Therapeutic Hypothermia. If accepted, allow infant to cool passively (switch off radiant heater) and monitor temperature (every hour) and BP every 15 minutes. Transfer urgently (within 6 hours). Outborn Infants referred from other hospitals 1. Request referring hospital to contact Regional Neonatal Unit RJMH (Belfast) for urgent transfer for Therapeutic Hypothermia and advise to cool passively and monitor as above. 2. If no cot available in RJMH and all of the following criteria are met: o Level 1 cot available in Antrim NICU. o NICU has <15 infants. o Cooling equipment available for this patient. o The infant s transfer to Antrim Hospital Neonatal Unit will be completed by 5 hours of age to allow establishment of the operational procedure. The referring hospital should be advised to passively cool the infant if possible. Operational procedure Equipment 1. CritiCool Cooling Therapy System 2. Disposable rectal temperature probe, Ref EU/

5 3. Disposable skin temperature sensor, Ref / Core sensor adaptor Grey (colour coded for connection to CritiCool), Ref Not Disposable 5. Surface sensor adapter Green (colour coded for connection to CritiCool), Ref Not Disposable 7. Cooling wrap Infant Thermo Wraps Disposable a. Choose appropriate size b. No 3118, Infants 2.5 to 4.0 kg c. No 3121, Infants 4.0 to 7.0 kg d. This end baby s head 5

6 8. Connecting Tubes (Part No ) Not disposable Wrap Connection CritiCool Connection 9. Lubricant and Tape for inserting and securing rectal probe. 10. Male connector for draining water tank (Part No ) Not disposable. Procedure for cooling NB: Complete cot side cooling documents (Appendix B) and maintain cot side seizure chart (Appendix A) Establish immediate dialogue with parents/family regarding the infant s needs and hypothermia as a new standard of care. Issue parent information leaflet, adapted from TOBY study parent information leaflet. Nurse infant on radiant warmer bed (ventilated or not) as usual procedure, but servo temperature control will not be used (temperature is regulated via the CritiCool equipment). Nurse infant naked: No nappy or wraps. No hat Do not nurse on a sheepskin, or on a water bag. Do not use glad wrap. If ventilated, maintain humidifier at usual temperature Continuous invasive blood pressure monitoring by indwelling arterial line (preferably umbilical) for the 72 hours duration of cooling and 12 hours rewarming. Insert multi-lumen umbilical venous line for ease of IV access during cooling and re-warming phase. All arterial blood gases analyses at 37 o C (i.e. do not adjust for baby s actual temperature). Fill CritiCool water tank with tap water until water level between the 2 red lines at the top of the water tank. 6

7 Switch on the CritiCool machine (switch at the back of machine) the default operation mode is Cooling Therapy and this is the only mode of operation used at any time. A detailed instruction manual is kept with the CritiCool. Connect the ports of the connecting tubes to both the ThermoWrap and the CritiCool machine and release the clamps. The ThermoWrap will now fill with water this need to happen before the baby is attached to the ThermoWrap cooling blanket. Insert Rectal Probe into the rectum at least 5cm: tape at approximately10cm to the upper inner thigh. It is very important that the probe is in at least this far to accurately measure the baby s core temperature the probe is designed for this purpose and will not cause mucosal trauma. Leave the probe in for 84 hours (72 hours cooling and 12 hours rewarming) The probe does not need to be removed for cleaning Connect core (rectal) and surface (skin) probes to CritiCool monitor These are colour coded and marked. Set CritiCool core temperature at 33.5 o Celsius during the 72 hour cooling period. The temperature is adjusted using the up and down arrows. Documentation (nursing): Documentation (medical): Maintain a separate Seizure chart (Appendix A ). Record rectal and skin temperature hourly, in addition to NICU routine. All other documentation as per routine intensive care documentation. Rectal temperature to be maintained at 33.5 o C for 72 hours Duration of cooling (72 hours) and rewarming (12 hours) as follows: Cooling started Date : : Time : Rewarming to start Date : : Time : 7

8 Rewarming to stop Date : : Time : Medical and nursing care are as usual (eg, fluid management, anticonvulsants, blood gases and glucoses) Investigations /assessment to be made in cooled infant (suggested): Admission Day 1 Day 2 Day 3 ABG FBC Coagulation screen ± Glucose LFT s U&E, Ca, Creat. Sarnat staging (criteria) Cranial U/S MRI - requested for days age Cooling requirements may decrease with treatments that reduce metabolic rate Anticonvulsants Sedatives Muscle relaxants Analgesia / sedation Consider morphine and/or midazolam (if ventilated) or paracetamol (rectally when nil orally, even with rectal probe in-situ and even if not all retained in rectum). Irritability is common and often related to HIE Shivering like tremors are common in infants with milder encephalopathy Stop cooling following discussion with Consultant if there is: Worsening or severe PPHN Severe coagulopathy Arrhythmia requiring medical treatment (not sinus bradycardia) Decision made to withdraw life-support as determined by and at the discretion of the attending Consultant with the family. Rewarming After 72 hours cooling Increase the core temperature on the CritiCool machine by 0.5 o C every 2 hours until core temperature is 36.5 o C Rewarming will take 12 hours aiming for core temperature of 36.5 degrees Celsius. Remove rectal probe and discard Take infant out of the ThermoWrap cooling blanket once rewarming is complete Apply normal temperature skin probe and radiant warmer as per usual practice in NICU. Empty CritiCool water tank Clamp the connection tubes of the ThermoWrap cooling blanket Disconnect the ThermoWrap ends of the connecting tube and attach the male connector (for drainage of the tank) to one of the tubes (over the sink as drainage will start immediately) see earlier pictures. 8

9 Disconnect the connecting tubes from the CritiCool machine, switch off and return to storage following usual cleaning procedures after patient use. Follow-up All surviving infants treated with Therapeutic Hypothermia should be referred to the Neonatal outpatient clinic and Neonatal Neurodevelopmental clinic References 1. Jacobs S, Hunt R, Tarnow-Mordi W, Inder T, Davis P. Cooling for newborns with hypoxic ischaemic encephalopathy. Cochrane Database Syst Rev 2007; (4): CD TOBY trial reference 3. Azzopardi D et al, Moderate hypothermia to treat perinatal asphyxial encephalopathy, NEJM 361; 14, 1 October 2009 Dr Hugo Lambrechts Associate Specialist Dr Sanjeev Bali Consultant Neonatologist January

10 APPENDIX A 10

11 (Affix Patient ID Label) Antrim Hospital Neonatal Unit Seizure Chart for Therapeutic Hypothermia Date Time Description of Seizure Duration Action Taken 11

12 APPENDIX B 12

13 (Affix Patient Label) Documentation: Therapeutic Hypothermia This documentation is supplementary to the full Therapeutic Hypothermia guideline for the Neonatal Unit, and should be used in conjunction with the full guideline. Its purpose is to facilitate documentation at the cot side and enable audit. Please ensure that any adverse events or side-effects are documented on the last page. Should cooling be discontinued, please document clearly the reasons for this and ensure that the rewarming protocol is still followed. Admission Date: : : Time of Admission: : Referral Source o Delivery Suite o Causeway Hospital o Other Specify:.. If born outside NHSCT, was bed availability in RJMH checked? YES/ NO If outborn, age of infant on arrival to Antrim NNU:... Consultant:. 13

14 (Affix Patient Label) Criteria for starting Therapeutic Hypothermia satisfied? - Consider 1 to 4 below () 1. Gestational age > 35 weeks 2. Less than 6 hours of age 3. Moderate or severe HIE - Several clinical criteria in either category (Sarnat and Sarnat staging): Grading of HIE (admission) Moderate Severe Moderate HIE Severe HIE Consciousness Lethargic Comatose/ obtund Activity Decreased Absent Posture Distal flexion Decerebrate (complete extension) Tone Hypotonic Flaccid Primitive reflexes Weak suck, gag & Moro Absent suck, gag & Moro Pupils Constricted Deviated, dilated, non-reactive Heart rate Bradycardia Variable Respiration Periodic Apnoeic 4. Evidence of peripartum hypoxia/ ischaemia - at least 2 of: o Apgar score of 5 or less at 10 minutes Score:. o Mechanical ventilation (ETT/ bag/ neopuff) or need for resuscitation at 10 minutes o Cord ph < 7.0 or, blood gas ph < 7.0 or base deficit > 12 within 1 hour of birth Actual ph (Cord): Base excess:.... Actual ph (first blood gas): Base excess:. 14

15 (Affix patient label) Reasons for not starting Therapeutic Hypothermia Check that none of the contra-indications below are applicable Inability to commence Therapeutic Hypothermia within 6 hours of birth Birth weight < 2 kg Major congenital abnormalities Severe clinical coagulopathy Death appears inevitable Documentation: Rectal (Core) temperature to be maintained at 33.5 o C for 72 hours Duration of cooling (72 hours) and rewarming (12 hours) as follows: Cooling started: Date : : Time : Rewarming to start: Date : : Time : Rewarming to stop: Date : : Time : Medical and nursing care are as usual (e.g., fluid management, anticonvulsants, blood gases and glucoses) 15

16 (Affix patient label) Admission Test () Time Result Sarnat Staging () Time: Moderate ABG ph pco2 po2 Bicarb BE FBC Hb Severe WCC Plt Coagulation PT APTT Fibrinogen U+E/ Ca/ Glucose LFT s Na K Urea Creat Ca Glucose Total Bili Direct Bili ALP AST GGT T Protein Albumin 16

17 (Affix patient label) Day One Date: : : Test () Time Result Sarnat Staging () Time: Mild ABG ph pco2 po2 Bicarb BE FBC Hb Moderate WCC Plt Coagulation U+E/ Ca/ Glucose LFT s PT APTT Fibrinogen Na K Urea Creat Ca Glucose Total Bili Direct Bili ALP AST GGT T Protein Albumin Severe Ultrasound Brain: 17

18 (Affix patient label) Day Two Date: : : Test () Time Result Sarnat Staging () Time: Mild ABG ph pco2 po2 Bicarb BE FBC Hb Moderate WCC Plt Coagulation U+E/ Ca/ Glucose LFT s PT APTT Fibrinogen Na K Urea Creat Ca Glucose Total Bili Direct Bili ALP AST GGT T Protein Albumin Severe 18

19 (Affix patient label) Day Three Date: : : Test () Time Result Sarnat Staging () Time: Mild ABG ph pco2 po2 Bicarb BE FBC Hb Moderate WCC Plt Coagulation (Only if still clinically indicated on Day 3) U+E/ Ca/ Glucose LFT s PT APTT Fibrinogen Na K Urea Creat Ca Glucose Total Bili Direct Bili ALP AST GGT T Protein Albumin Severe MRI Booked (10 to 14 days)? 19

20 (Affix Patient Label) Rewarming Rewarming started (Increase to 34 C): Date : : Time : After 2 hours, Increase to 34.5 C: Time : After 2 hours, Increase to 35 C: Time : After 2 hours, Increase to 35.5 C: Time : After 2 hours, Increase to 35.5 C: Time : After 2 hours, Increase to 36 C: Time : After 2 hours, Increase to 36.5 C: Time : Time target core temperature of 36.5 C achieved: : Remove Cooling equipment and reconnect incubator surface temperature probe and servo temperature control. Lowest temperature recorded on CritiCool since start of Cooling:... C Water Tank emptied? 20

21 (Affix patient label) If Cooling discontinued, state reasons: State any adverse events/ side-effects (Other than seizures on seizure chart): Event Action Taken 21