Uses of Error

Back when I was a research fellow and doing an obstetrics and gynaecology locum in another hospital, the phone rang at 04·00 h—an 18-yearold primigravida at 36 weeks’ gestation was being rushed to hospital in an ambulance. She had had a convulsion at home and the paramedics reported that she was fi tting again. When I saw her in the delivery suite, making a diagnosis of eclampsia was easy: her blood pressure was 170/110 mm Hg and there was 4+ proteinuria. The patient was resuscitated, a loading dose of 4 g of magnesium sulfate was given, followed by an infusion of magnesium sulfate started at 1 g per h, to be infused for 24 h. We took the patient to theatre for defi nitive treatment of her condition— delivery of the baby. The patient was transferred to the operating table. Suddenly her feet and hands were blue and oxygen saturations of 50% were recorded. “Respiratory arrest”, shouted the anaesthetist. I recalled that cardiopulmonary resuscitation is universally unsuccessful in the third trimester, unless the uterus is emptied. The baby was delivered immediately by caesarean section and was fi ne. I started to suture the uterus. The anaesthetist informed me that the patient was still not breathing 3 min after respiratory arrest. We came to the conclusion that she had had a massive intracranial bleed. I then glanced at the magnesium sulfate infusion—it was empty! What had transpired was that, before delivery, as the patient was being transferred from her maternity-bed to the theatre-bed, the drip was also transferred from the delivery-suite drip-counter to the theatre-suite dripcounter. The drip had not been blocked off during the transfer and the patient had received an immediate dose of 25 g of magnesium sulfate. This overdose resulted in her respiratory arrest. After frantic phone calls and 72 h in intensive care, the patient returned to the postnatal ward. Departments now do not own their drip-counters. It is the property of the patient until the clinical need ceases; in all settings, drips are not transferred to a diff erent drip-counter once an infusion has started. That’s our drip counter!