Doctors are perceived—by patients and clinicians—as being the captain of the health care team, with good reason. But, physicians may spend only 30 to 45 minutes a day with even a critically ill hospitalized patient, whereas nurses are a constant presence at the bedside and regularly interact with physicians, pharmacists, families, and all other members of the health care team. Of all the members of the health care team, nurses therefore play a critically important role in ensuring patient safety by monitoring patients for clinical deterioration, detecting errors and near misses, understanding care processes and weaknesses inherent in some systems, and performing countless other tasks to ensure patients receive high-quality care.
Nurse staffing and patient safety
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.
The nurse-to-patient ratio is only one aspect of the relationship between nursing workload and patient safety. Overall nursing workload is likely linked to patient outcomes as well. A sophisticated 2011 study showed that increased patient turnover was also associated with increased mortality risk, even when overall nurse staffing was considered adequate. Determining adequate nurse staffing is a very complex process that changes on a shift-by-shift basis, and requires close coordination between management and nursing based on patient acuity and turnover, availability of support staff and skill mix, and many other factors. The process of establishing nurse staffing on a unit-by-unit and shift-by-shift basis is discussed in detail in an AHRQ WebM&M commentary.
Nursing skill mix and training may also be linked to patient outcomes. One classic study showed lower inpatient mortality rates for a variety of surgical patients in hospitals with more highly educated nurses. This finding has resulted in calls for all nurses to have at least a baccalaureate education. Irrespective of educational level, the quality of nurses' on-the-job training may also play a role in patient outcomes. As discussed in an AHRQ WebM&M commentary, nurses do not currently have a standardized transition to independent practice training requirement (analogous to medical residency training). Less experienced nurses may therefore lack mentorship and training in dealing with systems issues and complex clinical scenarios.
Nurses' working conditions and patient safety
The causal relationship between nurse-to-patient ratios and patient outcomes likely is accounted for by both increased workload and increased stress and risk of burnout for nurses. Missed nursing care—a type of error of omission in which required care elements are not completed—is relatively common on inpatient wards. In one British study, missed nursing care episodes were strongly associated with a higher numbers of patients per nurse. Burnout among clinicians (both nurses and physicians) has consistently been linked to patient safety risks, and some studies show that higher numbers of patients per nurse is correlated with increased risk of burnout among nurses.
The high-intensity nature of nurses' work means that nurses themselves are at risk of committing errors while providing routine care. Human factors engineering principles hold that when an individual is attempting a complex task, such as administering medications to a hospitalized patient, the work environment should be as conducive as possible for carrying out the task. However, operational failures such as interruptions or equipment failures may interfere with nurses' ability to perform such tasks; several studies have shown that interruptions are virtually a routine part of nurses' jobs. These interruptions have been tied to an increased risk of errors, particularly medication administration errors. While some interruptions are likely important for patient care, the link between interruptions and errors is one example of how deficiencies in the day-to-day work environment for nurses is directly linked to patient safety.
Longer shifts and working overtime have also been linked to increased risk of error, including in one high-profile case where an error committed by a nurse working a double shift resulted in the nurse being criminally prosecuted. Nurses who commit errors are at risk of becoming second victims of the error, a well-documented phenomenon that is associated with an increased risk of self-reported error and leaving the nursing profession. In their daily work, nurses are also frequently exposed to disruptive or unprofessional behavior by physicians and other health care personnel, and such exposure has been demonstrated to be a key factor in nursing burnout and in nurses leaving their job or the profession entirely.
All of these factors—the high-risk nature of the work, increased stress caused by workload and interruptions, and the risk of burnout due to involvement in errors or exposure to disruptive behavior—likely combine with unsafe conditions precipitated by low nurse-to-patient ratios to increase the risk of adverse events. Using a systems analysis perspective, active errors made by individual nurses likely combine with these aligned holes in the "Swiss Cheese Model of Medical Errors" to result in preventable harm.
The National Quality Forum endorsed voluntary consensus standards for nursing-sensitive care in 2004. These included patient-centered outcomes considered to be markers of nursing care quality (such as falls and pressure ulcers) and system-related measures including nursing skill mix, nursing care hours, measures of the quality of the nursing practice environment (which includes staffing ratios), and nursing turnover. These measures are intended to illustrate both the quality of nursing care and the degree to which the working environment at an institution supports nurses in their patient safety efforts.
The Magnet Hospital Recognition Program, administered by the American Nurses Credentialing Center (a subsidiary of the American Nurses Association), seeks to recognize hospitals that deliver superior patient care and, partly on this basis, attract and retain high-quality nurses. The program has its genesis in a 1983 study that sought to identify hospitals that retained nurses for longer than average periods of time. The study identified institutional characteristics correlated with high retention rates, an important finding in light of a major nursing shortage at the time. These findings led 10 years later to the formal Magnet Program.
As of March 2011, 15 states and the District of Columbia have enacted legislation or adopted regulations around nurse staffing ratios. Mandatory overtime for nurses is also restricted in 16 states.