Patient Safety and Quality Improvement: Medical Errors and Adverse Events

After completing this article, readers should be able to: This is the first in a series of articles to review the topics of patient safety and quality improvement in pediatrics.Patient safety is a subject that traverses all medical specialties and affects every health-care professional. The attention to medical errors and adverse events as well as the resultant literature has grown exponentially over the past decade. A number of practicing physicians, however, remain unaware of the extent of the problem, the impact on patients, and the burden on the health-care system. Many also are unfamiliar with strategies to reduce the risk of harm.It is important to note that definitions used in patient safety can vary across studies, between organizations, and over time. A medical error, as defined by the Institute of Medicine (IOM), is “the failure to complete a planned action as intended or the use of a wrong plan to achieve an aim.” (1)(2) It is a mistake in action or judgment. A medical error must be distinguished from an adverse event, which is “an injury caused by medical management rather than by the underlying disease or condition of the patient.” An adverse event results in harm to the patient. Not all medical errors lead to adverse events. In fact, most do not. A medication error is the most common type of medical error (3)(4) and can occur at any point in the medication management process. (5) This chain of events includes ordering, transcribing, preparing, delivering, and administering a drug. Medication errors can be classified as errors of commission or omission. (6) An error of commission occurs when an incorrect action is taken, such as prescribing ceftriaxone for a neonate who has hyperbilirubinemia. An error of omission results when a correct action is not taken, such as not premedicating a patient who has a history of red man syndrome with an antihistamine before administering vancomycin.An adverse drug event (ADE) is an injury due to a medication. ADEs are the most common type of adverse events. Fortunately, less than 1% of medication errors result in an ADE. (5) A preventable ADE is an ADE that, based on the medical information known at the time, could have been avoided, such as a patient who has a known allergy to macrolides being prescribed azithromycin and developing urticaria. This occurrence is in contrast to a nonpreventable ADE, which could not have been foreseen based on the medical information known at the time. For example, a patient who has no known allergies is given azithromycin and develops urticaria. An adverse drug reaction is synonymous with a nonpreventable ADE. It is an event defined by the World Health Organization as “noxious and unintended, and which occurs at doses used in man for prophylaxis, diagnosis or therapy.” (7)(8)A potential ADE is a medication error that places a patient at significant risk of injury but does not actually result in harm. (7) Potential ADEs often are referred to as “near misses.” There are two subtypes of potential ADEs: intercepted and nonintercepted. An intercepted ADE is an error that is identified and corrected before it reaches the patient. For example, a patient is prescribed an overdose of ranitidine that is detected by a pharmacist, who does not dispense the drug, but instead refers the prescription back to the prescriber for correction. A nonintercepted ADE is an error that reaches the patient but, by pure happenstance, does not cause harm to the patient. For example, a patient is prescribed and given an overdose of ranitidine without suffering any ill effects. The Figure shows the relationship among medication errors, ADEs, and harm.A sentinel event is “an unexpected occurrence involving death or serious physical or psychological injury, or the risk thereof.” (9) An ADE or a potential ADE may qualify as a sentinel event. Not all sentinel events are the result of a medical error. A never event, as described by the National Quality Forum, is one of 28 events resulting from an error in medical care that is serious, unambiguous, and usually preventable. (10) Never events, which also are referred to as serious adverse events, serious reportable events, and serious reportable adverse events, never should occur within a health-care institution and generally signal a system safety failure.Patient safety has become a national health-care focus over the past 10 years, but medical errors and adverse events have been addressed for a far longer time. The investigators for the Harvard Medical Practice Study reviewed more than 30,000 records from patients discharged in 1984 from 51 hospitals across the state of New York. (11) Adverse events occurred in 3.7% of these hospitalizations, most of which were preventable. (12) If generalized to all hospitals in the United States, this incidence translates to more than 1 million people experiencing an adverse event and approximately 180,000 patients dying from an adverse event every year. (7) Medication-related incidents were the most common type of adverse event, at a rate of 0.7 ADEs per 100 admissions. (5)(12) A study of nearly 15,000 discharges across 28 hospitals in Utah and Colorado in 1992 identified 459 adverse events. (13) Fifty-eight percent of these adverse events were found to be preventable. In a study of more than 4,000 admissions at two large Boston hospitals over a 6-month period in 1993, investigators identified 247 ADEs. (14) This translates to 6.5 ADEs per 100 admissions, a rate greater than nine times that found in the Harvard study. Twenty-eight percent of the ADEs were considered preventable. These investigators also identified 194 potential ADEs, of which 43% were intercepted before they reached the patient.The IOM released its landmark report To Err is Human at the end of 1999, heralding a new age for the field of patient safety. (1) Extrapolating the results of the Utah-Colorado study and the Harvard study over the 33.6 million admissions to United States hospitals in 1997, the report estimated that 44,000 to 98,000 patients die from medical errors annually. The IOM issued recommendations in four strategic areas to improve patient safety: leadership and knowledge, identifying and learning from errors, setting performance standards and expectations for safety, and implementing safety systems in health-care organizations.The financial impact of medical errors and adverse events is enormous. Based on the IOM report, the estimated cost of medical errors in the United States is $37.6 billion annually. Preventable adverse events comprise an estimated $17 to $29 billion, more than 50% of which represent direct costs to the health-care system. (1)(2) An ADE extends the length of hospital stay by 1.74 to 2.2 days and increases costs by $2,000 to $3,200. A preventable ADE extends the hospital stay by 4.6 days and increases costs by $5,800. (14)(15)(16) These figures represent dollar values from the 1990s; current estimates are likely even higher.The financial burden of adverse events is shifting toward health-care institutions. Medicare no longer reimburses the cost of treatment for some events occurring during a hospital admission, and many state Medicaid agencies are considering similar financial disincentives. Private third-party payers may begin pursuing similar practices.The prevalence of medical errors and adverse events in children is becoming clearer. Investigators analyzed a subset of data from the Utah-Colorado study representing more than 3,700 pediatric hospitalizations, including birth admissions. (17) They found that adverse events occurred in 1% of these hospitalizations, 60% of which were deemed preventable. Extrapolated to the entire United States population, approximately 70,000 hospitalized children experience an adverse event each year, of which 42,000 could be avoided. Children have been recognized as a high-risk population for medication errors and ADEs. The risk for an ADE is estimated to be three times higher in hospitalized children than in adults. (4)(18) In a prospective study of medication orders in a children's hospital, 23.7% contained errors. (19) In a study of more than 10,000 medication orders representing 1,120 patients across two children's hospitals, the investigators found 5.7% of the orders contained errors, with 1.1% representing potential ADEs. (18) They identified 2.3 ADEs per 100 admissions, 19% of which were preventable. In a more recent study across 12 children's hospitals, investigators reported a rate of 11.1 ADEs per 100 patients, 15.7 ADEs per 1,000 patient-days, and 1.23 ADEs per 1,000 medication doses. (20) Rising ADE rates actually may reflect an improved ability to detect such events over time rather than a true increase in incidence.For many reasons, children are more vulnerable to medication errors and ADEs. Unlike adults, for whom dosing tends to be a single or limited number of options, dosing for children usually is tailored to the patient based on his or her weight. Proper dosing requires that the prescriber have an accurate weight for the child as well as the proficiency to perform weight-based calculations. Many settings in which children are treated are predominantly adult-oriented, with pediatric patients comprising only a small fraction of admissions. In such venues, staff may not always be trained in safe pediatric medication practices, and if they are, their skills may wane due to the infrequency of providing care to these young patients. Most drugs are packaged commercially for adult use. Such preparations require compounding for pediatric usage, a task that requires a specific skill set. The need for this additional step in the medication delivery process introduces risk of error and, therefore, risk of harm. (4)Children who experience extended lengths of stay, complex medication regimens, and higher severity of illness are at increased risk of ADEs. (21) Neonates and young infants are at even greater risk due to their immature hepatic, renal, and immune systems. (4)(22) In settings such as the neonatal intensive care unit, where lengths of stays often are measured in months, patients can have significant changes in weight over the course of a hospitalization. This change requires vigilance to assure that medication dosing regimens remain within safe and therapeutic ranges.Medication errors and ADEs occur in the community as well, although this venue has been less researched. (6)(23) In a prospective study across six outpatient offices, 14% of pediatric patients experienced an ADE. (24) Twenty-three percent of these events were judged to be preventable. Again, complex medication regimens increased the likelihood of preventable ADEs. Of note, parents whose English proficiency was limited were less likely to report an ADE, which may represent a subpopulation of children at even greater risk of harm.Not all outpatient errors and preventable adverse events are iatrogenic; they also can be caused by well-meaning parents and nonmedical caregivers. Many over-the-counter children's medications are available in a variety of preparations and concentrations, which can contribute to confusion and subsequent dosing errors. Outpatient medication errors and ADEs are not limited to oral drugs. For example, in 2007, a 17-year-old athlete died of salicylate toxicity from excessive use of over-the-counter topical sports ointments. (25) A tragic event such as this underscores the need for pediatricians to take every opportunity to stress to patients and families the importance of using medications only as instructed and the potential hazards of using seemingly benign drugs inappropriately.Difficulty in identifying medical errors and adverse events creates a significant barrier to assessing risk reduction strategies. Although the data presented in this article are staggering, they are likely to represent considerable underestimates. In the absence of an accurate, reliable methodology to measure errors and events, the ability to assess the impact of patient safety initiatives remains challenging. Historically, identification of medical errors and adverse events relied on incident reports, a methodology that has many pitfalls. The reporting of incidents presumes that an individual recognizes a medical error or an adverse event when it occurs. If an error or adverse event is identified, staff may assume, mistakenly, that someone else will report it. Incident report forms generally require a large amount of information, which makes them both time-consuming and cumbersome to complete. Personnel who do take the time to report events often receive no feedback. They may not see their efforts resulting in noticeable improvement, which can act as a disincentive for reporting subsequent events. (26)Staff may have valid apprehensions about reporting errors and adverse events. (27) There is a natural hesitancy to point out one's own mistakes for fear of being labeled incompetent and a reluctance to point out others’ mistakes for fear of being labeled a whistleblower. Although institutions across the country are transitioning to a culture of blameless reporting, staff still may worry about discipline by their institutions or licensing organizations. Fear of litigation also remains a major deterrent.Chart reviews in search of medical errors and adverse events are time- and labor-intensive. The cost often is prohibitive, and generally only a sampling of records can be evaluated. Trigger methodology can streamline the process and help capture occurrences that otherwise might go undetected. A trigger is an action or indicator that might signal the presence of an adverse event. For example, flumazenil usually is prescribed in response to a benzodiazepine-related ADE. An order for flumazenil, therefore, can serve as a trigger. Groups of triggers have been combined into trigger tools to increase the ability to identify actual and potential ADEs. (28) The resultant focused chart reviews save time and resources by improving efficiency. Trigger methodology has been applied in children's hospitals and has been shown to increase detection of ADEs. (20)The general public is becoming increasingly aware of issues of patient safety. A study reviewing newspaper articles over a 10-year period found increasing coverage of pediatric medication safety. (29) The United States had the highest absolute number of articles of the five countries included in the study. Nearly two thirds of the articles covered specific adverse events. The good news is that three quarters of the articles were written in a tone characterized as neutral, a positive step as health care transitions from a culture of individual blame to one of system-based improvement. Patients and families often know when they have experienced an adverse event. They may observe worsening of clinical status, the need to perform additional testing, or adjustments made to treatments. They may perceive a change in the behavior of the physician or other staff. They may overhear conversations between staff members. Patients and families want to be told when an error has occurred. They want to know what happened, why it happened, how it will affect their health, and what is being done to prevent such an error from recurring. (30)Informing patients and families when medical errors cause harm is the right thing to do, but despite physicians’ best intentions, full disclosure of such events is uncommon. Practitioners often fear that such disclosure may result in litigation, loss of trust by the patient and family, or tarnishing of their professional reputation. Health-care professionals must overcome the instinct to ignore, hide, or worst of all, deny when an adverse event occurs. Disclosure relieves the anxiety of not knowing and reaffirms an open, honest physician-patient-family relationship. Such transparency has been demonstrated to decrease litigation as well as the average settlement amount for claims that are filed. (30)(31)(32)Patients and families also want an apology. An apology historically has been viewed as an admission of guilt, and for this reason, practitioners often ignore their instincts to say “I’m sorry.” However, this omission is perceived as cold, heartless, and impersonal by patients and families. They correctly feel angry and distanced, which is toxic to the physician-patient-family relationship and actually may increase the likelihood of litigation. The importance of an apology and the reluctance by physicians to provide one due to fear of litigation has resulted in legislative changes. As of January 2008, 35 states have enacted statutes that prevent an apology from being used against a physician in a law suit. (30) Other states have similar legislation in progress. The impact, effectiveness, and protection afforded by these recent statutes have yet to be established. Policies vary across organizations, and legislation varies among states. Health-care professionals should consult risk management experts or legal counsel for guidance with disclosure of adverse events and saying “I’m sorry.”Although patients are the primary and most visible victims of medical errors and adverse events, it is important to remember the “second victims”: the clinicians. (33) The emotional impact of medical errors on health-care personnel, especially those errors that cause harm to patients, should not be underestimated. In many cases, more than one clinician is involved and may feel responsible. Resultant feelings of guilt, anxiety, or incompetence can be devastating, leading to inappropriate behaviors such as lashing out at patients, families, and colleagues and to unhealthy behaviors such as substance abuse. Health-care professionals must be supportive and nonjudgmental of their colleagues when medical errors occur. can provide a therapeutic venue to not only the medical of the event, but also the emotional issues as they to the safety initiatives can be within a public health of (27) The disease are to is medical errors, and for this medication errors. It is for physicians’ efforts to focus on the step in the medication management process at which errors most occur. The of primary is to reduce the incidence or risk of For example, the of the is to prevent or decrease the likelihood that a patient will become ill from the For medication errors, is no but for errors includes a of strategies. The is a of that can be by in any setting to help prevent errors and adverse drug events primary strategies also can be physician order refers to a of prescribing systems that have been shown to decrease medication errors and ADEs. can that information is included in an order or prescription using and can the of with pediatric can that dosing remains within safe in many systems for allergies and drug of available to drug concentrations, and of order is not a may help some but it can new of error. For example, can incorrect orders in some of requires an in and financial The cost of the remains for many institutions. In a less than of United States hospitals had systems order forms with can provide a for that all information is included in an but they or provide the of an on has been shown to be of primary in including of drug, dosing and help reduce errors and preventable ADEs. the cost in and financial resources this for many to detect and in the course of drugs such as are prescribed identification of to for medication safety is the detection and of errors into the medication management them before they have the opportunity to become preventable ADEs. of medication orders by pediatric has been shown to be an of potential ADEs from the and should be and to orders and the prescriber when an error is should be rather than by these each harm to a patient.The of is to with patients whose has been by a of For patient safety, available such as for and systems in such as response may help reduce the and with adverse events when they do to reduce and that increase risk of For this is public health to and to reduce disease For patient safety, increasing of the problem, an of this systems that the risk of error and them before they have an opportunity to cause and a culture in which safe are the error and event reporting is and improvement is the