Consensus Guidelines for the Management of
Insulin-Dependent (Type 1) Diabetes — Chapter 5

5.0 SPECIAL MANAGEMENT PROBLEMS

5.1 Pregnancy in women with diabetes
5.2 Management of diabetes during surgery
5.3 Diabetic ketoacidosis

IDDM CONSENSUS GUIDELINES Chapter 5 SPECIAL PROBLEMS: Pregnancy

5.1 Pregnancy in women with diabetes

Without appropriate care during pregnancy:
perinatal mortality may be more than 10 %, and
the rate of major congenital malformations 2-5 times higher
than in non-diabetic pregnancies;
With proper care from before conception
outcome can be comparable to non-diabetic women.

• Diabetic pregnancy is a high-risk state for both the woman and her fetus.
• Complications related to diabetes include:
  • development and progression of diabetes complications;
  • miscarriage, stillbirth, intrauterine death, and macrosomia;
  • congenital malformation, increased perinatal mortality rate and neonatal morbidity.

5.1.1 Management recommendations

5.1.1.1 Pre-pregnancy management

Before conception:

• optimize metabolic control
• educate about diabetic pregnancy
• normalize blood pressure
• treat sight-threatening retinopathy

5.1.1.2 Care of established diabetic pregnancies

Joint obstetric care is often best given in designated centres. The team consists of a diabetologist, an obstetrician, an ophthalmologist, a neonatologist, and a diabetes teaching nurse.

• Aim for normal blood glucose levels at conception and throughout the pregnancy by appropriate educational support, regular self-monitoring of blood glucose and frequent (weekly or biweekly) review.
• Target blood glucose values should be as close to normal as possible, while avoiding hypoglycaemia:
  • Fasting blood glucose <5.6 mmol/l (<100 mg/dl);
  • Post-prandial blood glucose <8.0 mmol/l (<145 mg/dl);
  • Glycated haemoglobin close to the upper limit of normal.
• A multiple insulin injection regimen may suit the motivated pregnant woman, and may aid those not achieving acceptable blood glucose control.
• Food intake should be adequate to maintain maternal and fetal nutrition; frequent small meals may facilitate improved blood glucose control.
• Regular fundal examination is needed (pre-pregnancy, at diagnosis, at the end of the first trimester, and in weeks 20-24 and 30-34. Early laser photocoagulation should be given if necessary.
• Avoid destroying the normal experience of pregnancy through over zealous application of medical technology.

5.1.1.3 Obstetric care

• Antenatal care should be every 2 weeks until week 34, then weekly.
• Ultrasound examination should be performed at least three times during pregnancy.
• Fetal monitoring should include cardiotocography weekly from week 34 and continuously during labour.

5.1.1.4 Care during labour and after delivery

• Pregnant diabetic patients should normally be delivered at term.
• Diabetes is not an indication for caesarean section.
• During labour, diabetes can be well controlled with intravenous infusion of glucose and insulin with frequent blood glucose measurement.
• A neonatal intensive care unit should be available close to the delivery room.
• It is important to watch for a rapid reduction in insulin requirement at delivery.

5.1.2 Special problems of diabetic women of childbearing age

Contraindications to pregnancy may include:

• severe nephropathy with decreased renal function
• advanced ischaemic heart disease
• unresponsive proliferative retinopathy
• older women
• teenage girls
• very poor glycated haemoglobin (HbA1 >12.0 % or HbA1c >10.0 %) ketoacidosis in early pregnancy

For contraception:

• The diabetic woman may use mechanical barrier methods, or oral contraceptives ((tri)sequential low-dose oestrogen/progesterone, or low dose progesterone, with medical supervision).
• If pregnancy is desired, contraception should not be withdrawn until after at least 2 months of adequate metabolic control.
• It may be desirable for the diabetic woman to have her children early in life (before diabetes complications can develop) and to settle for less children.

IDDM CONSENSUS GUIDELINES Chapter 5 SPECIAL PROBLEMS: Pregnancy

IDDM CONSENSUS GUIDELINES Chapter 5 SPECIAL PROBLEMS: Surgery

5.2 Management of Diabetes during Surgery

The aims of peri-operative management are:

• to avoid hypoglycaemia particularly during anaesthesia;
• to avoid excess metabolic decompensation and thus impaired phagocyte function, delayed wound healing, and increased thrombo-embolic risk.

To achieve this aim implies a local care protocol, and professionals familiar with its implementation.

5.2.1 Management Guidelines

• Optimize blood glucose control if time permits; targets as above .
• Delay major surgery if possible when fasting glucose >10.0 mmol/l, or post-prandial >13.0 mmol/l (or HbA1 >10.0 %, HbA1c >8.0 %).
• Screen for complications which may complicate surgery (cardiac or renal problems, autonomic or peripheral neuropathy, proliferative retinopathy).
• Manage peri-operatively on an IV glucose-insulin-potassium infusion regimen ( GIK ). Start at 0800 h and continue until the patient is eating normally. Dual (interconnected) insulin/glucose infusion is an alternative that can have advantages where greater flexibility of dosage is required.
• Monitor blood glucose before, during, and after (1-4 hourly) surgery using reagent strips or other rapid devices, used by trained personnel subject to continuing quality assurance.
• Aim to keep the blood glucose safely between 6.0 and 10.0 mmol/l
• Treat hypoglycaemia with glucose and restart GIK at lower insulin dose ¸ never stop intravenous insulin infusions.
• Return to normal timing of insulin injections as soon as practicable.
• Encourage supervised self-management while in hospital.

Use of glucose-insulin-potassium (GIK) regimens

• Use 500 ml 10 % (100 g/l) glucose (dextrose) containing:
  • Unmodified (soluble, regular) insulin 16 U
  • Potassium chloride 10 mmol
  infused at 80 ml/h from a volumetric pump.
• Consider higher dose (20 U) if obese, or initial blood glucose high
• Consider lower dose (12 U) if very thin, usual insulin dose low
• Adjust dose by –4 U if glucose falling and normal or low
• Adjust dose by +4 U if glucose rising or high
• Continue the GIK infusion until 30-60 min after first meal
• Use higher strength glucose solutions if water volume a problem
• Check for dilutional hyponatraemia daily

IDDM CONSENSUS GUIDELINES Chapter 5 SPECIAL PROBLEMS: Surgery

IDDM CONSENSUS GUIDELINES Chapter 5 SPECIAL PROBLEMS: Ketoacidosis

5.2 Management of Diabetic Ketoacidosis

Ketoacidosis can kill - but death is nearly always preventable

Death from ketoacidosis can usually be avoided by:

• early diagnosis
• careful monitoring of plasma K+
• avoidance of rapid swings in osmolality
• attention to coma care.

5.2.1 Management guidelines

• Ensure care protocols are available together with professionals experienced in their use.
• A fast and co-operative emergency laboratory is important.
• Look for infection by urinalysis, chest X-ray, blood cultures. Do not rely on temperature and leucocytosis. Have a low threshold for antibiotic treatment. In the absence of infection consider other contributory disease.
• Fluid replacement is by:
  • 2 l of isotonic saline (0.15 mol/l) given over the first 4 h
  • 2 l over the next 8 h, then
  • 1 l every 8 h.
  • Consider colloid if systolic blood pressure <100 mmHg after 2 h.
  • Use hypotonic solutions only if plasma Na+ >155 mmol/l, and then only as 1 l over 8 h.
  • Monitor central venous pressure if the patient has cardiac disease.
  • Be more cautious in the elderly.
• Insulin:
  • is best infused at 6 U/h.
  • Check lines and double dose if no response in 2 h.
  • If no pump use a paediatric giving set or give insulin IM (20 U followed by 6-10 U/h).
• Potassium:
  • Give 20 mmol/h from the time of initiation of insulin infusion.
  • Discontinue temporarily if laboratory K+ is greater than 6.0 mmol/l.
  • Check every 1.5-2 h.
  • If potassium falls below 4.0 mmol/l, increase accordingly.
  • Continuous ECG monitoring is a helpful guide to acute changes.
• Bicarbonate:
  • Only use if pH is 6.9 or less.
  • If indicated, give 100 mmol with 20 mmol K+ over 30 min.
  • Repeat blood gases 30 min later.
• When blood glucose falls to <13 mmol/l, replace the insulin infusion with a glucose-insulin-potassium regimen, initially 500 ml 10 % (100 g/l) glucose (dextrose) containing 24 U unmodified (soluble, regular) insulin and 20 mmol K+ infused at 80 ml/h. Aim for blood glucose in the range 10.0-13.0 mmol/l, by changing the insulin concentration as required. When able to eat transfer to subcutaneous insulin therapy.
• Insert a nasogastric tube if the patient is comatose;
• Insert a urinary catheter no urine passed within 3 h;
• Heparinize if in coma or very hyperosmolar (>350 mOsm/l).

IDDM CONSENSUS GUIDELINES Chapter 4 LATE COMPLICATIONS: Ketoacidosis