4.2. Anaesthetic problems 

• Uncontrolled hypertension. 
• Imminent convulsions. 
• Hypovolaemia (shift of fluid). 
• Electrolyte imbalance: sodium may be low because of diet and diuretics. The potassium level may be low because of the use of diuretics. 
• The magnesium level in the blood may be high if oliguria is present. Magnesium is excreted through the kidneys, so if an oliguric patient has been treated with magnesium sulphate, look for signs of magnesium toxicity. Prolonged neuromuscular block is common, potentiating non-depolarising drugs. Note however that magnesium improves renal blood flow and hence urine output. 
• The foetus is premature, placental function is impaired and foetal hypoxia is likely. 
• The foetus is often depressed because of decreased placental blood flow or as a result of the drugs used in treating of the eclampsia. 
• Inadequate pain relief may cause the blood pressure to increase further and result in convulsions. 
• Pulmonary oedema causing hypoxia. 
• Detoxification and excretion of drugs are interfered with because of impaired liver and renal function in severe cases.