Case narrative: medical misadventure and the case of Chloe

Chloe is a 3-month-old infant who was brought to the emergency department by her parents after developing a fever. Over the past 18 hours, she has become increasingly fussy and refused to nurse. While Chloe was being weighed in the triage room, her parents inquired about her weight in pounds, a number quickly provided by flicking a switch on the scale that changed the reading from metric (5.4 kilograms) to English (12 pounds) units. The nursing team was about to change shift and a nurse who was recording the weight heard Chloe’s weight as 12 pounds and recorded this number on the triage chart. This weight was then entered as the kilogram dose calculation weight in Chloe’s electronic medical record by a medical technician. During her evaluation, Chloe appeared ill, and displayed signs of moderate dehydration. Her laboratory findings were consistent with a urinary tract infection and she was admitted for intravenous antibiotic treatment with ampicillin and gentamicin; these drugs were ordered via the computerized provider order entry system, the doses calculated based on the infant’s recorded weight. During the order entry, several message boxes appeared on the computer screen providing hospital announcements. Additionally, a warning box appeared questioning the doses of both antibiotics as excessive given the age of the patient. The provider in the emergency department, who had been on-duty for 14 hours at that point, was distracted and clicked all the dialogue boxes closed, permitting the order to be signed. The ampicillin was infused while Chloe was in the emergency department; the gentamicin dose arrived at her bedside just before she was transported to her acute care inpatient room. The emergency department nurse connected the gentamicin syringe to Chloe’s IV pump, and the acute care nurse activated the pump upon arrival at Chloe’s room. Over the next 12 hours, Chloe’s urine output did not normalize despite appropriate fluid resuscitation efforts. While evaluating her low urine output, she was weighed again and this new weight was recorded in her nursing notes. During change of nursing shift, Chloe’s nurse reviewed her charting notes and recognized that the weight being used for the medications was over twice the correct weight and realized that the two antibiotics were overdosed. Chloe’s nurse then called the on-call hospitalist to report the two medication errors. Because gentamicin can cause kidney and hearing damage, the level of Chloe’s gentamicin level was checked and was found to be markedly elevated at 25 mcg/ml. Her serum creatinine had increased from 0.8 on admission to 3.5 mg/dl, suggestive of rapidly worsening kidney function.