Nurses vigilance at the bedside is essential to their ability to ensure patient safety. It is logical; therefore, that assigning increasing numbers of patients eventually compromises nurses' ability to provide safe care. Several seminal studies have demonstrated the link between nurse staffing ratios and patient safety, documenting an increased risk of patient safety events, morbidity, and even mortality as the number of patients per nurse increases. The strength of these data has led several states, beginning with California in 2004, to establish legislatively mandated minimum nurse-to-patient ratios; in California, acute medical–surgical inpatient units may assign no more than five patients to each registered nurse.
