Ketogenic diet for the inpatient setting
Dietary therapy for epilepsy
The ketogenic diet is an established and effective therapy for children with intractable childhood epilepsy and the treatment of choice in children with GLUT-1 deficiency or pyruvate dehydrogenase deficiency. It is a medically supervised, high fat, low carbohydrate and restricted protein diet that maintains a chronic state of ketosis whilst providing adequate calories and protein to maintain normal growth. The ketogenic diet (KD) mimics the fasting state in the body, shifting the main source of energy for the body from carbohydrates to fats. In this state, the brain can derive energy from the ketone bodies produced.
Medications and Dietary Therapy for Epilepsy (DTE)
If you need to give medication other than the child’s routine medications please check the carbohydrate content prior to administration. Tablets are generally preferred. Children on the ketogenic diet should not be given liquid formulation of any medications due to the high carbohydrate concentration they contain. This includes antibiotics, analgesics, antihistamines and antiepileptic medications.
See Appendix for further details.
In general:
Do not use IV medications, elixirs, syrups, chew-tabs or enteric coated tablets unless checked by a pharmacist for formulation with lowest carbohydrate content. Please note not all tablet formulations of medications necessarily have the lowest amount of carbohydrate
Discuss all new medications with clinicians or pharmacist
If the total carbohydrate in the medication is greater than 0.5g/day, adjust the carbohydrate composition of the diet with your Dietitian as required
Inform dietician as soon as possible of changes to any medications
Management of Acute Illness and Complications
When the child is unwell, the DTE should take second place to the necessary treatment needed. However it should be recognised that abrupt loss of ketosis can significantly exacerbate seizure control. Wherever possible sugar/CHO-free medications and IV treatments should be used and avoidance of loss of ketosis should be the goal.
Measurements should be done at any time of fasting e.g., on waking in the morning or if meals are missed or are not completed due to poor appetite. Hyperketosis or hypoglycaemia should be treated quickly.
Hyperketosis can occur when fasting. Check ketones 6 hourly until ketosis is stable. Ideal ketosis for seizure control is at levels of 2.4-5.0 mmol/L on blood testing.
If blood ketone levels are greater than 5.0 mmol/L, the child may be symptomatic:
Facial flushing, nausea +/- vomiting, lethargy/tiredness, rapid, shallow breathing
If symptomatic give the 30 mL of juice or 15 mL of 24% sucrose solution, or 3 mL of Hypofit Gel (3 grams of CHO) and repeat the blood ketone reading after 30 minutes. If more than 2 rescue treatments required, perform blood gas analysis for degree of acidosis and notify consultant. If NBM can give 2 mL/kg 10% glucose (200 mg/kg glucose) IV to treat symptomatic hyperketosis.
Blood glucose levels should also be monitored whilst the patient is unwell. If not tolerating diet, hypoglycaemia can be a concern. Check glucose levels 6 hourly until patient stable. Ideal levels for blood glucose 2.5-5 mmol/L on blood testing.
If blood glucose levels are less than 3 mmol/L, the child may be symptomatic:
Sweating, dizziness, becoming cold and clammy, jittery, confused if blood glucose levels are <2.5 mmol/L, or <3mmol/L and symptomatic, give 30 mL Twist Juice, or 15 mL of 24% sucrose solution, or 3 mL of Hypofit Gel (3 grams of CHO). Repeat levels 20 mins post treatment. You can repeat treatment a 2nd time if glucose levels remain low. If blood glucose level remains low post 2nd treatment, call for a review.
If NBM can give 2 mL/kg of 10% glucose (200 mg/kg glucose) give 60 mL of 5% glucose IV to treat symptomatic hypoglycaemia, and consider infusion if ongoing hypoglycaemia as per Starship Clinical Guidelines.
a) Vomiting & Diarrhoea
The DTE should be stopped and clear fluids that are low in carbohydrate (water, sugar-free cordial and flat sugar-free lemonade) should be offered to ensure adequate hydration. If enterally fed, use 50% diluted feed at a continuous rate to meet fluid requirements. If intravenous fluids are required, saline at an appropriate strength to the child’s age and requirements should be used. It may however become necessary to add dextrose to the solution if there are concerns regarding hypoglycaemia or intravenous fluids are required for a prolonged length of time. Regular ketone and blood glucose testing should be conducted throughout the day to pre-empt the development of hyperketosis.
When vomiting has subsided the DTE should be reintroduced gradually with half the usual meal quantities for the first 24-48 hours or as per tolerance. If the child is unable to complete the meals, the meal ingredients should be mixed together e.g., scrambled egg recipe/custard recipe so that each mouthful will contain the adequate proportions of fat and carbohydrate. If fat tolerance is a problem, the amount of fat in the diet may be reduced temporarily (24-48 hours) and increased gradually as tolerated. For the patient who is tube-fed, half strength feeds or full feeds at a slower rate may be given for 24-48 hours and gradually built up to usual maintenance as tolerated over a few days.
b) Other illness
Infection may cause a drop in ketones but once the child has recovered from the offending illness, ketosis should gradually return. For colds and influenza, the diet should be continued if possible and cold medications should be avoided as very few are CHO free however Pharmac funded crushed paracetamol tablets may be used if required.
Each child will be given an individualised sick day plan by the dietitian at discharge.
Other precautions
The Ketogenic diet is an effective treatment in children with refractory epilepsy. However it can be associated with side effects including kidney stones. If the child presents with unexplained pain, then urinalysis for haematuria should be also be performed. If unsure of ketone levels a finger prick can be performed and acceptable level is 2.4-5mmol/L.
Admission for procedures including general anaesthetic
Inform ketogenic dietitian of planned admission in advance
Regular ketones and glucose monitoring every 6 hours
If NBM, use standard protocol (6 hours food, 2 hours clear fluid)
If IV fluids required use 0.9% saline or similar without glucose unless blood glucose levels are low
If anaesthetic is longer than 3 hours, monitor blood glucose, ketones, pH and HCO3 2 hourly and consider IV bicarbonate if increasing acidosis
Continue IV 0.9% saline until low CHO oral fluids tolerated
Re-introduce the diet as soon as possible. Contact the child’s dietitian for advice if required.
Useful contacts for any inquiries
Dietary therapy for Epilepsy dietitian, Nicole Hill – 021917930 or email nicolehill@adhb.govt.nz
Starship Ketogenic Nurse Specialist, Christina Lampey – 021351072 or email CLampey@adhb.govt.nz
Starship Neurology Nurse Specialist, Catherine Campbell – 021894939 or email RLloyd@adhb.govt.nz
Starship Neurology Nurse Specialist, Erin Skidmore - 021923750 or email SSNeuroNrs@adhb.govt.nz
Primary Neurologist involved with this patient – or contact the Paediatric Neurologist on call.
Appendix 1:
Minimising carbohydrate content of medications on the ketogenic diet
(adapted from http://www.gosh.nhs.uk/health-professionals/clinical-guidelines/ketogenic-diet)
An unrecognised source of carbohydrates in the ketogenic diet is prescription and over the counter medications. If the carbohydrate content of medications is not considered, ketosis can be affected and thus seizure control may be compromised.
Consider if addition of the new medication is absolutely necessary
Where possible minimise the sugar and carbohydrate contained in drugs and IV solutions
If in doubt, substances ending in “ose” or “ol” are usually converted to glucose in the body (cellulose is an exception and is suitable)
In most cases the use of syrups, elixirs, and chewable tablets should be avoided as these generally contain more carbohydrates than other dosage forms
Many liquid preparations may be labelled sugar free but often contain sorbitol. This is not suitable for use in the ketogenic diet and should be minimised wherever possible
Medications using saccharin as the sweetener are suitable
Medications in suppository form are suitable for use on the ketogenic diet
If you are unsure of the carbohydrate content of medications, you should contact your Ward pharmacist, the ketogenic team or the manufacturing company directly.
Once the carbohydrate content of the new medication has been established, contact the dietitian to see if the diet needs to be altered to accommodate the new medication. Increased frequency of ketone testing will help to determine the impact the addition of the medication has had on the diet.
Check with the pharmacist if products high in carbohydrates can be substituted for low carbohydrate alternatives, and if certain medications can be crushed or dissolved without affecting the integrity of the medication. The pharmacist will also check that the child will get an equivalent dose of medication if the formulation is changed.
When the child is discharged from hospital, inform their GP and local paediatrician that the child is on the diet so any additional medications prescribed are as low in carbohydrate as possible.
Carbohydrate containing excipients (ingredients)
Ingredients which are sources of carbohydrate:
Sugars: dextrose, fructose, glucose, lactose, sucrose, sugar
Starches: cornstarch, pregelatinized starch, sodium starch glycolate, sodium starch glycolate
Sorbitol
Mannitol
Xylitol
Maltitol
Isomalt
Erythritol
Alcohol
Glycerin
Hydrogenated Starch Hydrolysates (HSH)
Ascorbic acid
Ingredients which are not sources of carbohydrate:
Cellulose
Carboxymethylcellulose
Hydroxymethylcellulose
Microcrystalline cellulose
Polyethylene glycol
Magnesium stearate
Aspartame
Saccharine
Asulfamine potassium (K)