The purpose of this guideline is to provide guidance about blood glucose monitoring at Great Ormond Street Hospital (GOSH).
- Receiving intravenous or subcutaneous insulin (Rationale 6).
- Receiving medication that can alter blood glucose levels, e.g. octreotide, diazoxide
- Receiving intravenous glucose solutions, this includes parenteral nutrition
- Nil by mouth for 4 hours without intravenous fluids
- Nil by mouth and receiving only intravenous fluids for more than 12 hours
- Commencing parenteral nutrition and during 'wind down' of cyclical parenteral nutrition until stable (Rationale 7)
- With some endocrine and metabolic conditions, e.g. congenital hyperinsulinism and glycogen storage disease
- With blood glucose levels outside of normal parameters 4-7mmol/L or parameters as specified by local policy and medical instruction specific to child‘s condition (Rationale 8)
- Post-operatively as per local guidelines, i.e. procedure specific
- Presenting with seizures and/or unexplained loss of consciousness
- Commencing steroid therapy
- Following a ketogenic diet
- intrauterine growth retardation
- infants of insulin-dependent diabetic mothers
- hypoxic ischaemic encephalopathy
- haemolytic disease of the newborn
- other syndromes e.g. Beckwith-Weidermann
- metabolic metabolism disorders, e.g. galactosaemia, glycogen storage disease
Inform child and family
- that the monitoring of blood glucose is necessary
- the reason for monitoring
- the implication of the result
- what it entails
- the proposed duration of the procedure
- for neonates, follow the capillary blood sampling clinical guideline
- under one year - side of heel (Naughton 2005).
- over one year - side of fingertip or toe; avoid thumb and index finger (Rationale 15)
- meter is dropped.
- unexplained blood glucose levels versus clinical appearance of child
- Trust approved meter such as Accu-chek® Inform II or Accu-chek® Performa meter
- The correct strips for the meter to be used, that are in date and with the lid closed (Rationale 26)
- non-sterile gloves and an apron
- non-sterile gauze - avoid use of cotton wool (Rationale 27)
- sharps bin (Rationale 28)
- blood glucose chart or appropriate alternative electronic record
- a retractable puncture device as supplied by the Trust (Rationale 28 and 29)
Obtaining a measurement
- Wash and ensure site is clean, dry and free from glucose contamination (Rationale 30).
- Perform hand hygiene (Rationale 31).
- Put on non-sterile gloves and apron (Rationale 31).
- Prepare meter immediately before sampling: Follow touch screen directions on the Accu-Chek® Inform II once logged in. Inserting strip into Accu-Chek® Performa meter turns it on automatically ready for use (Rationale 32).
- Puncture the skin using retractable lancet device, or take the sample from an arterial line (see guideline for arterial line sampling) (Rationale 33).
- You may wipe away first drop of blood, however if the sample site has been observed to be washed and dried, then the first drop will suffice (Hortensius et al 2011) (Rationale 34).
- Gently squeeze or massage area to create tear drop size of blood (Rationale 35).
- Place the edge of strip to the drop of blood.
- Test area will draw in the blood sample.
- Ensure window on strip is completely filled with blood (Rationale 36).
- Apply non-sterile gauze to the puncture site and apply pressure (Rationale 37 and 38).
- Ensure bleeding has stopped and child is comfortable (Rationale 39).
- Wait for result to be displayed on meter.
- Read off result (displayed in mmol/L). The Accu-Chek® Inform II and Performa meter’s result range is 0.6 and 33.3mmol/L.
- If the monitor reads 'LO' it indicates a blood glucose of <0.6 mmol/L. If the monitor reads 'HI' it indicates a blood glucose of >33.3 mmol/L.
- Record the result on the blood glucose chart or electronic charting (Rationale 40).
- Dispose of used equipment according to the Waste Policy (Rationale 41).
- Perform hand hygiene (Rationale 42).
- At handover, check the most recent blood glucose level is within acceptable limits in accordance with the clinical management plan (Rationale 8).
- Regularly placing the Accu-Chek® Inform II meter in the docking units enables charging of the meter and uploading of results to the Chemical Pathology Lab.
Contraindications associated with extra-laboratory blood glucose measurement
- If peripheral circulation is impaired, collection of capillary blood from the approved sample sites is not advised as the results might not be a true reflection of the physiological blood glucose level. This may apply in the following circumstances: severe dehydration as a result of diabetic ketoacidosis or due to hyperglycaemic hyperosmolar non-ketotic syndrome, hypotension, shock, decompensated heart failure NYHA Class IV, or peripheral arterial occlusive disease.
- Blood concentrations of Galactose>0.83 mmol/L will cause overestimation of blood glucose results (normally galactoseis <0.28 mmol/L). Therefore glucometers must not be used in patients with a known or suspected diagnosis of galactosaemia. Such patients must be monitored using laboratory glucose results only.
- Haematocrit values should be between 10-65%.
- Intravenous (IV) infusion of ascorbic acid will cause overestimation of results.
- Lipaemic samples (triglycerides) in excess of 20.3 mmol/L may produce elevated results.
On completing the procedure
Blood glucose monitoring sheet
Rationale 1: To achieve an accurate reading. Untrained staff may obtain inaccurate or misleading results that can lead to incorrect management and adversely affect the patient.
Rationale 2: To meet the manufacturer’s recommendations.
Rationale 3: Children with Hyperinsulinism should not have blood glucose of less than 3.5mmol/L without intervention as are unable to produce alternative fuel sources such as ketones and are therefore at high risk of brain damage (Hussain et al 2007). A lower level of 3.0mmol/L (Campbell 2008) may be accepted for children with other conditions before intervention but the named consultant for individual patients must direct this.
Rationale 4: To initiate appropriate intervention and management.
Rationale 5: To promote involvement and enable partnership in care.
Rationale 6: Monitoring is necessary for dose adjustment.
Rationale 7: To avoid blood glucose levels rebounding above and below normal levels as a result of change to rates and subsequently a rapid change to glucose administration.
Rationale 8: To initiate appropriate intervention and management.
Rationale 9: To exclude meter error and incorrect results.
Rationale 10: To obtain informed consent.
Rationale 11: To aid efficiency.
Rationale 12: To promote safety.
Rationale 13: To promote involvement and enable partnership in care.
Rationale 14: To minimise the risk of cross infection.
Rationale 15: To avoid affecting the pincer grip and fine motor skills.
Rationale 16: To prevent damage to underlying structures, e.g. nerve endings (Jain et al, 2001; Naughten, 2005).
Rationale 17: Continued use of the same puncture site can lead to the area becoming sore and the development of calluses (Naughten 2005).
Rationale 18: To prevent pain and tissue damage (Naughten 2005).
Rationale 19: Alcohol toughens the skin when used frequently.
Rationale 20: Alcohol and whit soft paraffin can interfere with strip and meter analysis and may give incorrect results.
Rationale 21: To minimise the child’s distress.
Rationale 22: To promote involvement.
Rationale 23: Untrained staff may obtain inaccurate or misleading results that can lead to incorrect management and adversely affect the patient.
Rationale 24: The Accu-Chek® Inform II Glucose Meter is intended to provide an audit trail; therefore identification of each user is important.
Rationale 25: To aid efficiency.
Rationale 26: Out-of-date strips and exposing test strips to moisture may give incorrect results.
Rationale 27: Cotton wool fibres can interfere with strip and meter analysis and may give incorrect results.
Rationale 28: To promote safety and prevent needle stick injury.
Rationale 29: To achieve optimum depth of penetration.
Rationale 30: To prevent incorrect test results.
Rationale 31: To minimise the risk of cross infection.
Rationale 32: To facilitate analysis.
Rationale 33: To obtain blood sample.
Rationale 34: To reduce risk of contamination and ensure circulating blood is measured.
Rationale 35: To encourage blood flow to the site.
Rationale 36: To obtain accurate and reliable results.
Rationale 37: To prevent further bleeding.
Rationale 38: To prevent haematoma formation.
Rationale 39: To promote safety and comfort.
Rationale 40: To maintain accurate records.
Rationale 41: To adhere to hospital policy.
Rationale 42: To minimise risk of cross infection.
Rationale 43: To initiate appropriate intervention and management.
Rationale 44: To promote involvement and enable partnership in care.
Rationale 45: To avoid damaging the device.
Rationale 46: To adhere to manufacturer’s instructions.
Campbell IW (2008) Hypoglycaemia (low blood sugar) in diabetes. netdoctor (e-pub)
Gilbert C (2009) Investigation and management of congenital hyperinsulinism. British Journal of Nursing 18 (20): 1256-1260.
Hanas R (2015) Type 1 diabetes in children, adolescents and young adults. Class Publishing, London. Edition 6th edition.
Hussain K, Blackenstein O, De Lonlay P and Christessen HT (2007) Hyperinsulinaemic hypoglycaemia: biochemical bias and the importance of maintaining normoglycaemia during management. Archive of Diseases in Childhood 92 (7): 568-570.
National Patient Safety Agency (2010) Prevention of over infusion of intravenous fluid* and medicines in neonates.
Naughten F (2005) The heel prick: how efficient is common practice? RCM Midwives 8 (3): 112-4.
Jain A, Rutter N and Ratnayaka M (2001) Topical amethocaine gel for pain relief on heel prick blood sampling: a randomised double blind controlled trial. Archives of Diseases in Childhood, 84 (1): 56-59.
Hortensius J, Slingerland RJ, Kleefstra N, Logtenberg SJ, Groenier KH, Houweling ST, Bilo HJ (2011) Self-Monitoring of Blood Glucose: The Use of the First or the Second Drop of Blood. Diabetes Care, 34(3): 556-560 Self-Monitoring of Blood Glucose: The Use of the First or the Second Drop of Blood. Available at: https://www.ncbi.nlm.nih.gov/pubmed/21289231
Medicine and Healthcare Products Regulatory Agency (2010) Management and use of IVD point of care test devices DB20