Errors in Medicine: A Perioperative Perspective

Sanjay  Sharma

Errors in Medicine: A Perioperative PerspectiveCHAPTER 1

Sanjay Sharma

INTRODUCTION

There is increasing emphasis on minimizing medical errors, which have been described as “an act of omission or commission in planning or execution that contributes or could contribute to an unintended result”.¹ Realistically, this would include both the implementation of an inappropriate plan, or a good plan not executed as intended. These errors are usually unintentional and not malicious or deliberate.

The errors of omission or commission, in both planning and execution of various processes, are included irrespective of whether the adverse outcome actually occurred or was likely. It thus provides a useful template for research into faulty processes that contribute to majority of errors that could fly under the radar, as they do not actually cause harm. Equally, it takes focus away from trivial “slip ups” that do not have the potential to actually result in an adverse outcome.

The healthcare industry is inspired by, and follows the model of the airline industry by investigating every near miss and error. This initiative, to analyze each event irrespective of whether it actually eventuates in a bad outcome, would improve reliability and safety. The healthcare industry aspires to achieving this level of investigation in the absence of a culture of blame.

As opposed to unplanned errors, the term violation applies to planned and deliberate deviation from accepted protocols and standard operating procedure.² Violations may sometimes involve extenuating circumstances with pressures of time or staffing, and also include deliberate flouting of rules in some instances. Omission of an appropriate preoperative assessment, waiving the “time out” process, and omitting to check the anesthetic machine prior to commencement of procedure all constitute violations.

Moyen et al.³ clearly defined these errors, but then also further defined medication errors, especially those that were preventable. Other definitions, with errors subdivided into slips and lapses have also been alluded to, and these will be discussed further in the chapter.2

INCIDENCE

There is increasing recognition and attention to medical errors irrespective of the actual severity of outcome. “The real problem is not how to stop bad doctors from harming, even killing, their patients. It is how to prevent good doctors from doing so”.⁴ The Institute of Medicine report,⁵ aptly titled “To Err is Human”, estimated that between 44,000 and 98,000 hospitalized patients die annually in the USA as a result of medical errors. Australian Healthcare Quality study,⁶ found that adverse events (unintended injury or complication caused by healthcare) occurred in 16.6% of hospital admissions, with 51% of these events judged to be “highly preventable”. UK report⁷ found that medical errors caused harm (death and injury) to in excess of 850,000 patients admitted to National Health Service Hospitals annually. Other reports, published worldwide, show widespread acceptance of the impact of medical errors on patients admitted to hospitals.^8–11

CLASSIFICATION OF ERRORS BASED ON CAUSATION—ACTIVE OR LATENT

Errors can broadly be classified into active errors as those occurring around an incident, and latent or systemic errors that may not be immediately evident or visible.¹²

Active errors are usually attributable to personnel directly caring for patients, such as nursing and medical staff. An example of an active error is inadvertent administration of a wrong medication, operation performed on wrong site, or even wrong patient. These errors may sometimes be one-off, due to carelessness or negligence, but sometimes a reflection of latent errors—an accident waiting to happen.

Latent errors are often systemic, resulting from poor planning or execution. In the scenario of a wrong medication being administered, the latent error potentially is that of two distinctly different medications packaged in similar looking ampoules, and placed close together on the trolley—an absolute recipe for disaster. This error would not be identifiable until an active error was made and attributed to this problem on one or more occasions.

Active Errors

Active errors, directly attributable to personnel, have further been classified into simple omissions such as slips and lapses, and a third category of fixation errors.^12,13 Slips and lapses are exactly occurring frequently when one is preoccupied or distracted and hence cannot focus appropriately on the job they are meant to do.¹² Slips and lapses can involve errors attributable to subconscious and conscious cognition.¹³3

Slips

Explanation of the etymology of slip suggests an unintended action or word, such as slip of the tongue or slip up. Rotating the wrong knob on an anesthetic machine, thus delivering nitrous oxide instead of air, is a classic example of anesthetic slip. Though slips seem fairly innocuous, they can sometimes result in adverse outcomes. Clarity on slips in anesthesia was provided by Norman¹⁴ who categorized slips into sequence errors, description errors, and mode errors.

Sequence errors: Elements of a task are all performed, but in an incorrect order or sequence. A typical example would be injection of muscle relaxant before actually giving induction agent.
Description errors: Correct action performed, but on the wrong agent or object. This is exemplified by an appropriate action such as turning off the knob, but wrongly the knob of nitrous oxide rather than oxygen.
Mode errors: Performance of correct action but the setting of equipment is in the incorrect or wrong mode. Once the circuit switch is set to ventilator mode, attempts to squeeze a breathing bag to ventilate the patient highlights a mode error.

Lapse

When an intended action is missed, often due to distraction or time pressure, it qualifies as a lapse. Leaving one's car unlocked and rushing into a shopping center is a typical example of a lapse. In clinical work, a lapse occurs when a medication is not given though it was intended to.

Fixation Error

This is a third variety of active error, seen more commonly in a crisis or stressful situation. Allnutt¹⁴ describes extreme concentration on one action at the cost of other more useful actions as “coning of attention”. He describes this tendency to focus on a particular task or source of information without “taking a step back” to review others options. Some emergency situations call for a change in plan or diagnosis but the persistent failure to recognize this and stick to the original unsuccessful action is a classic example of fixation error.¹⁵ An example would be the ongoing attempt to “fight” with a piece of jammed essential lifesaving equipment rather than picking an alternative which may be easily available.

Few common types of fixation errors are:

“This and only this”: In this scenario, the caregiver is fixated on a diagnosis and will not consider alternative plans despite investigations suggesting otherwise.4
“Everything but this”: Another variety where the caregiver does not acknowledge a major problem and hence this is left unattended, while minor issues are attended to.
“Everything's okay”: Similar to the above, where evidence is ignored to the detriment of the condition.

A classic example of fixation error was evidenced in a 1972 plane crash, where the crew gave all their attention to a defective indicator light. So fixated were they on this light that they ignored a major looming disaster with autopilot disengaging until the plane actually crashed.

Simulation exercises for anesthetic emergencies often display fixation errors, irrespective of the seniority and experience of the anesthesiologist.^16,17 A positive approach to this error and reflection on methods to avoid this in real life serves a purpose of simulation exercise.

Latent Errors

Why do errors occur repeatedly? Bogner's theory of error scripts—“all the men and women are merely players”.¹⁸ He suggests that the script may incorporate faults, which induce or provoke errors, and this sets the stage for adverse outcomes. The individuals held responsible are actually merely “actors” and should not be the focus of punitive action, since they are mostly “following a script”.

Anesthesia is unique in that one practitioner singlehandedly decides the medication to be administered, prepares, and administers it and then monitors the patient to ensure that no complication ensues. This is complex at the best of times, and provides a template for mishaps and errors especially in times of stress or crisis.

Recently, there have been news items relating to adverse outcome when tranexamic acid was injected intrathecally as the ampoule was similar to bupivacaine, and easily mistaken. Both had orange-colored lettering, and were placed side-by-side on a trolley. Another such potential disaster related to similarity between ondansetron and vasopressin causing accidental injection of the wrong agent. Errors relating to accidental intrathecal injection of chemotherapeutic agents meant for intravenous administration have been reported on many occasions both in UK and Australia.¹⁹ Despite extensive publicity, litigation and large payouts, beside a manslaughter conviction, these errors have recurred. It emphasizes the lesson from Bogner's theory that the script is error-prone. Two medications, one intended for intravenous administration and the other for intrathecal injection, are packaged similarly, in similar volumes, and presented to the doctor (“actor”) for administration. The error recurs despite changing doctors, because the script is unchanged.

Whilst medical errors resulting in adverse outcomes are often the subject of scrutiny, root cause analysis, and litigation, it is moot to remember that adverse outcomes actually follow only in a small proportion.5

Fig. 1: James Reason's “Swiss cheese” model of causation of errors.²¹ Typically, defense is formed by multiple layers, and when the holes align in the form of medical errors, a poor outcome ensues.

The larger proportion of errors or “near misses” may not be associated with adverse outcomes either due to good fortune, or to being noted and dealt with in a timely manner.^5,20

The Swiss cheese model of error causation proposed by James Reason has been extrapolated to healthcare.²¹ The principle of Swiss cheese theory suggests that several layers of defense are in place in most hospitals to protect against adverse outcomes relating to medical errors. These layers are represented by several slices of Swiss cheese, each with holes in them. These holes are representative of flaws in the system, predisposing to error. When a situation arises in which the holes in different layers align, or flaws “match up”, injury and adverse outcomes are likely as illustrated in Figure 1.²¹

IS THE TERM “ERROR” THE MOST APPROPRIATE AND SUITABLE?

Near miss,¹ incident, and accident^23,24 are other terms that have been used in some safety critical industries. However, the term error carries a connotation of stigma, and is often associated with negative psychological impact on the clinician. An antagonistic term that strongly promotes the blame game, an error can also be used as the basis for a malpractice claim.^25–27 This fear adds to feelings of anger, inadequacy, guilt, anxiety, and depression.^5,20,28 A negative approach such as this carries the potential to decrease efficiency of the “accused” clinician, sometimes even resulting in them giving up an otherwise good career in medicine.²⁰ It has been suggested that the term error be restricted to processes for redesigning of systems and improvement of patient safety. Identifying error and providing feedback and education have been acknowledged as good resources to improve patient safety.^5,20,29,30

6As per the Swiss cheese theory, multiple complex factors contribute to causation of errors.^12,22 The human factor needs to be factored into the understanding of error occurrence, which is often lacking given intolerance by public and the law. Prevention of errors is more likely to be resolved by education, as well as addressing underlying systemic causes, and not by punitive action against clinicians. Ultimately errors can be reduced or mitigated once health systems are safer, not by apportioning blame and punishing individuals.^5,20,22,31 Errors need to be recognized and acknowledged to then create educational opportunities and improvements in safety of healthcare.²⁶

ROLE OF HUMAN FACTORS IN GENESIS OF ERROR

Human factors involve the complex interaction between humans and environment or technology.²² In medical field, the subset most frequently studied was anesthesia and intensive care, which have similarities to previously studied fields such as engineering, design, management, and ergonomics.³² Not only is the field of anesthesia most studied for human factors in accident causation, but is also identified as significantly invested in strategies for patient safety.^33,34 With inspiration from aviation industry especially in relation to checklists, drills and simulation, this specialty has made rapid advances in use of technology for patient monitoring and implementation of safety guidelines. Analysis of human factor in causation of errors suggests 64–83% of anesthetic accidents can be linked to human error.¹³

The causes of human error in aviation mishaps were identified but not limited to long working hours causing fatigue with flawed cognition and decision making processes. Team issues relating to teamwork, leadership, and interpersonal communication all potentially contribute to human error.³⁵ Following this analysis, attempts were made to decrease errors through crew resource management (CRM), which has become increasingly sophisticated and had increasing uptake and approval.³⁶ Initial resistance was overcome with improved training and evidence of human factors in causation of accidents.

The specialty of anesthesia has followed the strategies implemented in the aviation industry toward safer practice. Besides technical skills and knowledge, anesthesiologists’ nontechnical skills (ANTS) including task management, teamwork, situation awareness, and decision-making are taught and assessed in the anesthesia training program.³⁷

“HIGHLY COMPLEX, TIGHTLY COUPLED”

Another similarity of anesthesia to aviation industry is that both are highly complex, dynamic, and tightly coupled. Not only are complex interactions 7involved in ensuring a good outcome, but also the unpredictable characteristics and responses of the human undergoing anesthesia make this more difficult and need personalized planning.^38,39

The term “tightly coupled” reflects the critical importance of time in the processes, which cannot wait or stand by.⁴⁰ Induction of anesthesia is a tight time dependent process, where medication is administered followed by paralysis and intubation. These need to be performed in quick succession. The anesthesiologist cannot afford to be distracted, or undertake some other task leaving patient unattended, without dire consequences. These highly complex time coupled systems set the stage for increased likelihood of accidents.¹² Perrow suggests that these accidents, very likely to occur in complex time coupled activities, should be viewed as inherent characteristics of such a system, so named “normal accidents”.⁴⁰

CHANGING APPROACH TO ERROR

The traditional approach to error has been to emphasize education and training, along with punitive measures and blame apportionment as a means of reducing errors and mitigating their effects.⁴¹ This was based on the premise that encouraging people to be more careful and motivated would improve safety by reducing errors. Whilst this seems obvious and straightforward, just focusing on individuals and pushing them to perform better has not really reduced accidents in industry analysis. The reason that person-focused approach has not worked is because accidents are often the result of interplay of systemic, organizational, and circumstantial factors rather than just one unsafe worker.³²

Whilst encouraging and motivating people to do better, the culture of “naming, blaming, and shaming” the person deemed responsible deflects from the bigger picture to actually analyze the cause of error.⁴² The premise that blaming an individual for carelessness, negligence, and poor motivation will somehow eliminate errors, is flawed.

One of the major “side effects” of this blame culture is inculcating fear, so errors are covered up rather than admitted to. Multiple factors contribute to this inability to acknowledge an error. The training of medical students and doctors has been to aim for zero errors, by being extra careful and trying hard. It follows that doctors then see themselves and their practice as infallible, which is really a setup for trouble. When an adverse event occurs, which is inevitable in some situations, doctors see this as a professional and personal failure, and fear the shame that will follow when colleagues see them as incompetent. The feelings of guilt, shame, and isolation are often major enough for the doctor to become the “second victim”.⁴³ It has been said that, “‥… medicine is often driven by the idea that perfection is possible and that mistakes are a personal and professional failure. This perfection mind-set … is laudable, admirable, and unworkable”.⁴⁴8

Recognition that errors are often based on complex interactions of human behavior with equipment and procedures forms the modern approach to understanding and addressing error. In contrast to the traditional approach, where human cognitive limitations have been targeted, the current approach is to accept these as the last link in events leading to adverse outcomes. It is accepted that fatigue and long hours of work, stress, preoccupation or distraction as well as forgetfulness can contribute to accidents, but this is certainly not the only major or leading cause of an adverse event.³² Acceptance of inevitability of errors in some situations and acceptance of human fallibility, besides designing and promoting safe systems is possibly the best way to improve safety.

CAUSATION OF ERRORS ALSO MIRED IN MYTHS

Reason⁴⁵ has listed some myths around error causation. These include:

Errors are made by bad people, casting a moral shadow of karma:⁴² Simply put, it suggests that people bring these bad events upon themselves, due to performing bad actions. This is clearly a myth, given that most errors occur to the best people performing the most difficult tasks or a good person having a bad day.
Errors are unpredictable and unpreventable: Another myth propagated around error causation relates to a perception of errors being random events, occurring without reason or warning. The reality is that errors do occur throughout a profession.
Highly trained individuals do not make errors: This is another myth, negated by the fact that errors are usual and common, though most are not associated with serious outcomes. Analysis from the aviation industry shows only about 100 major events a year on background of 100 million errors made by flight crew.⁴⁶
Highly trained individuals make huge errors: It is commonly believed that highly-trained professional makes huge errors invariably causing bad outcomes. However, similar to the previous myth, statistics show errors may be common, but serious adverse events are rare due good preventative systems in place (e.g. alarms on anesthetic machine). Also, individuals who are highly competent are also well trained to detect and recover from errors before they actually cause a bad outcome.

Errors are not uniformly viewed, and like everything else, are subject to bias. They are largely classified into outcome bias and hindsight bias.

Outcome bias depends on adverse outcome. The worse the outcome, the more seriously an error is viewed.⁴⁷ An interesting study where 112 anesthesiologists were asked their opinion about quality of care in 21 cases showed inverse relationship between worsening outcome and judgment of appropriate care.⁴⁸ Put simply, the same set of circumstances 9(in this case standard of care) was judged more critically (as being worse) when informed that it was associated with bad outcome.
The benefit of hindsight or retrospective analysis, once the outcome is known, definitely alters analysis of errors and adverse outcomes. Psychologists have studied and confirmed the phenomenon of this bias, when those reviewing a sequence of events after the outcome can clearly see disaster looming. On the other hand, an experienced person actually involved in real-time management of the events may not be able to see events unfolding in a linear fashion.¹²

MEDICATION ERRORS IN THE HOSPITAL

Staggering statistics from the United States show that nearly 10% of hospital inpatient costs are attributable to potentially preventable complications, of which medication error is a substantial contributor. Figures from 2006 estimated national healthcare costs at $940 billion, and the 9.4% contribution from errors equates to $88 billion.⁴⁹

One of the major errors encountered in health industry is that of drug administration errors. These are estimated to account for 7,000 deaths in the United States, and a much larger number of people suffering, along with increase health costs.^50–52 Medication errors have been documented as the seventh most common cause of mortality in hospitalized patients, with worst culprits being antibiotics and anesthetic agents.⁵³ Review and analysis of medication errors, and effective methods of prevention is one of the strategies pursued to reduce spiraling healthcare costs as well as adverse events.

Other studies have also substantiated the above figures relating to costs and morbidity from medication errors. Bates et al. have analyzed figures from a medium sized 700-bed hospital, and calculated 1 in 50 in patients have a preventable adverse outcome related to medications. This translates into increased hospital costs of $4,700 per admission or $2.8 million annually, which is considered preventable.⁵⁴

One of the top reasons of medication error during inpatient stay is linked to polypharmacy, given that a third of inpatients are on five or more different medications.⁵⁵ Newer medications may carry specific risks include drug interactions, and certain groups may be more susceptible to the adverse effects. The elderly population, with some age-related physiological changes including reduced ability to metabolize drugs, combined with needing a large number of medications, are at high risk of drug-related adverse outcomes. Research has shown increased incidence of adverse events in those over 65, possibly influenced by age-related decrease in renal function and polypharmacy.⁵⁶10

The other high-risk population is young children, as drug prescriptions need to be tightly linked to body weight. Patients with limited ability to understand and follow instructions would also be at risk of adverse events. A recent study showed that two-thirds of emergency hospital admission occurred due to unintentional overdosage of certain medications. Of these, only four groups, specifically warfarin, insulins, oral hypoglycemics, and antiplatelet agents, accounted for 7 out of 10 emergency hospital admissions.⁵⁷

Medications taken in error, if not prescribed can also result in significant adverse events. Specific groups of medications that have this potential include opioids, sedatives, antibiotics, potassium chloride and hypoglycemic agents, among others. Adverse events could potentially occur due to allergic response, even when medications are correctly administered. This is considered to be more commonly preventable in older population (90%) than in younger population (24%).⁵⁸

CLASSIFICATION OF MEDICAL ERRORS BASED ON IMPACT

A medication error index adopted by the National Coordinating Council for Medication Error Reporting and Prevention (NCC MERP) in 1996 was later revised in 2001. This index classifies errors based on impact to the patient, ranging from whether it actually affected the patient to the degree of harm resulting in temporary or permanent morbidity/mortality as depicted in Figure 2.

MEDICATION ERRORS SPECIFIC TO THE PRACTICE OF ANESTHESIA

Medication errors in anesthesia are a significant contributor to morbidity as well as mortality. Extrapolation from statistics suggests that most anesthesiologists would be involved in at least one major error over an average career, with about 7 errors per year.^51,53 Medication errors, in association with infusion pump problems, are reported to be the leading cause of deaths related to anesthesia in Denmark.⁵⁹ Studies from other regions and continents have shown similar results. A prospective study of 10,000 anesthesia episodes from New Zealand showed 1 error for every 130 anesthetics administered.⁶⁰ This along with some other studies listed in Table 1 highlights incidence of drug errors. In a Canadian survey less than 70% anesthesiologists reported adhering to practice of labeling syringes and reading labels before administration on a regular basis.⁶¹

Anesthesiologists are uniquely placed as the only subset in medical practice to prescribe, draw up, dilute, and administer drugs and then monitor patients for any complications. Given the high usage of medications for induction and maintenance of anesthesia, the urgency and sometimes crisis like situations, it is anticipated this will set the scene for errors associated sometimes with severe adverse outcomes.11

Fig. 2: National Coordinating Council for Medication Error Reporting and Prevention (NCC MERP, 2001).Source: 2014 National Coordinating Council for Medication Error Reporting and Prevention.80

Table 1 Incidence of medication errors in key studies.

Study	Study period	Number of anesthetics delivered	Incidence of drug error	Percentage of drug error
Webster et al.⁶⁰	Feb 1998– Oct 1999	10,806	81	0.75%
Sakaguchi et al.⁶⁵	1993–2007	64,285	50	0.078%
Llewellyn et al.⁶⁶	Jul 2005– Jan 2006	30,412	111	0.37%
Cooper et al.⁷⁰	Aug 2007– Feb 2008	10,574	52	0.49%
Zhang et al.⁸¹	Mar 2011– Sep 2011	24,380	179	0.73%

12An average anesthetic career would likely involve administration of 1 million anesthetics. A significant proportion of these would be elderly patients, presenting for high-risk surgery, sometimes in urgent and emergency situations. Drug interactions with medications the patients may currently be using, and failure to recognize or reconcile these can lead to disastrous situations. Emergency surgery and anesthesia can sometimes be dynamic and rapidly changing or deteriorating, which demands urgent medication possibly without rechecks.

Other potential confounders are the factors that influence the patient's ability to tolerate any errors, including reduced physiologic reserve due to emergency condition or trauma needing surgery, besides of course extremes of age, and other conditions such as pregnancy.

The numbers for intensive care units appear to be a little higher with 133 medication errors reported per 1,000 patient days.⁶² It has been acknowledged that a widespread pattern of under-reporting in most healthcare systems means that the actual rate of medication errors would actually be much higher.⁶³ Also, given that the actual outcome of an error is influenced by so many factors, studies need to focus and reflect on errors or near misses, irrespective of actual outcome of harm.

As discussed, medication errors are often attributable to failure of pathways, processes, and systems, rather than individual negligence. Lack of protocols for administration of medications, and shortage of staff to assists with checks and other processes are typical systemic latent causes of medication errors. Staff shortage can also result in some practitioners needing to work beyond reasonable hours leading to fatigue or distractions/interruptions from attempting to manage multiple cases. Australia and New Zealand College of Anaesthesia (ANZCA) has published statements on fatigue and distractions, and need for safe working hours. Active causes of failure or medication error include incorrect choice of medication or route of administration, and failure of memory or attention.⁶⁴

Studies have identified the most common medications administered wrongly. They include vasopressors, opioids, and cardio-stimulants.⁶⁵ A study by Llewellyn⁶⁶ from South Africa reported the most frequent cause of error as being due to mislabeling of drugs. Sakaguchi also suggested that most errors were attributable to inexperience of the practitioner involved in drug administration.⁶⁵ This issue was emphasized in many other studies, including one by Phillips, which correlated increased errors and the start of the new medical residents placement/rotation.⁶⁷

The Journal of Patient Safety reported incorrect medication as causing nearly half of medication errors (48%), followed by incorrect or excess dosage (38%), and inappropriate route of administration (8%). Smaller 13contributions of 4 and 2% respectively were attributable to administration of less dosage or missing out entirely.⁶⁸ The analysis further involved breakdown of causes for administration of incorrect medication as syringe swap in 42%, drug ampoule swap in 33%, and wrong choice of medication in 17%. Incorrect and excess dosages were administered frequently due to misunderstanding of dosage, wrong usage of syringe pump (21%), and incorrect use of dilution (5%).⁵³

Detailed breakdown of the actual process during which medication errors are most common revealed some interesting data.⁶⁹ Administration of any medication in intensive care units involves well over a hundred little steps, right from prescription to administration and monitoring. Though administration is usually double-checked between two medical personnel, it was the most common step for error (53%), far more than prescription (17%), preparation (14%), or transcription (11%). The commonly involved medications include heparin, potassium chloride, inotropes, and antibiotics, which are possibly the most commonly used medications in intensive care unit.

Analysis of medication errors in anesthetic practice⁷⁰ reported events as occurring more frequently during the maintenance phase of anesthesia (42%) as opposed to induction (28%) or when surgery is commenced (17%). Errors in administration of anesthetic agents could involve route or order of administration or the actual dosage. The usual medications associated with these errors include induction agents, anticholinergics, opioids and neuromuscular blocking agents, among others. An impressive study by Phillips⁶⁷ also suggested similar causative factors including incorrect dose (40.9%), incorrect medication (16%), and incorrect route (9.5%).

Another analysis of over 2,000 medication errors in anesthesia from Australia also showed 61% events occurred during the administration of drugs. Most commonly, it was administration of wrong drug that was implicated, but in about 7% it was a correctly labeled syringe with wrong drug in it. Miscommunication during provider change was identified as the cause of error.⁷¹

An important and not uncommon cause of medication errors is medications that have similar packaging, appearance, or labeling, but very different pharmacological properties, as alluded to earlier. Examples abound of medications packaged similarly with potential for confusion and error, and anesthesia specific drugs are overrepresented in this section. The neuromuscular blocking agents, cisatracurium and rocuronium, have different properties including onset and duration but have similar labeling.

While mortality occurs only in a small proportion of medication errors, the effects in many cases can be far reaching for both patients and healthcare professionals. Increased cost to the healthcare system from morbidity, readmission, prolonged hospital stays, lack of confidence, and 14litigation concerns in caregiver as well as damaged public perception are all consequences of these adverse events.

Table 2 Classification of drug errors.

Drawing up drugs and labeling phase	Similar looking vials
	Unlabeled syringes:
	Not checking the label (including expiry date) prior to administration
	Different concentration in the syringe and incorrect label (incorrect dilutions esp. relevant in pediatric patients)
Drug administration phase	Near misses:
	Incorrect dose (inadequate or in excess) esp. in pediatric patients
	Syringe swap:
	Wrong route of administration
	Incorrect timing of administration
	Omission, repetition, or substitution of drug
Documentation errors	Adverse event not recognized or not documented
	Reluctance among doctors to admit the error
	Failure to report an error during medication

Dhawan et al.⁷² simplified the classification (Table 2) of errors as applied particularly to anesthesia practice.

ERROR REDUCTION AND PREVENTION—HARM MINIMIZATION

While much work remains to be done in prevention of medication errors, attitudes toward this are most important in determining the success of any strategy. To this end, Ashcroft et al. studied safety culture in community pharmacies across United Kingdom. Attitudes toward safety ranged from a total lack of understanding for the need of any risk management strategies to an integration of risk reduction steps in every process.⁷³ They have classified attitudes toward medical errors as levels 1–5, from mast dangerous to most risk averse. Level 1 or “pathological” includes subjects who view risk management and safety issues as a waste of time. Level 2 is more “reactive” and responds to incidents appropriately, but actually waits for them to occur. Level 3 or the “calculative” group tries to plan in advance and anticipate possible scenarios. Level 4 is more “proactive” in that they are always on the alert, understanding the inevitability of errors, if the guard is dropped. Level 5 is “generative”, incorporating risk management strategies into every process, and constantly working toward risk minimization.

Worldwide efforts are underway in an effort to reduce the burden of medication errors. Bar coding of medications, reconciliation of electronic 15medical records, large labels highlighting high-risk drugs, and similar measures have been proposed and adopted in many institutions with an aim of reducing the burden of error. The reduction in errors was modest, and highlighted the need for finding alternative solutions to these complex problems. Some hospitals such as Virginia Mason have drawn on industry concepts such as Six Sigma to decrease variance and significantly improve safety in medication administration.⁷⁴

Another example of extrapolating quality concepts from industry is demonstrable at Froedtert Hospital systems in Milwaukee.⁷⁵ One main project relating to medication errors through the intravenous route elucidated lack of standardization as the most important cause. Six-Sigma approach was applied to identify systems errors and then implement methods to eliminate these errors. The causes highlighted as part of investigation included medication orders not received, defective faxes, lack of oversight, administration of medications on “standard” doses rather than adjusted for weight, and continuing these medications beyond necessary time frame.

Confirmation that errors were more often system issues and not just individual or personal carelessness then produced system solutions. Intravenous pumps were redesigned with up-to-date information on preparing standard medications, based on industry approach using Six Sigma. This will be the way forward in identifying system failures and suggesting safety measures, though cost is usually a limiting factor. With strong emphasis worldwide on harm minimization and risk reduction, some strategies have been implemented. Some potential systems for safer drug administration include but are not limited to the following:

VEINROM: This is a novel design (still in development) for administration of medications intraoperatively, using a predisposition syringe with interlocking mechanism. The acronym stands for vasoconstrictors, emergency drugs, neuromuscular blockers, induction agents, reversal agents, opioids, and miscellaneous drugs. Ports and syringes are color-coded. Bar code facilities allow the medication record to be updated simultaneously with administration.⁷⁶
ValiMed: This validation of medical systems device utilizes photoelectron spectroscopy to confirm the substance being administered when compared with control substance. This tabletop device uses ultraviolet (UV) light for ionization of electrons, and measures the energy of electrons to validate the drug being administered. During an extensive trial by Michigan health system, no drug error was reported during the duration of trial, and also reduced wastage of drugs. Constraints include cost and time required to run the test.⁷⁷16
Robot-assisted medication preparation: With accelerated progress of artificial intelligence and automation, robots are expected to undertake routine tasks of drug preparation and administration. A recent report from Italy (University of Ancona) showed no medication error after 19,000 (95%) chemotherapeutic drugs were prepared using robotic arm aid.⁷⁸
Purchase of prefilled syringes: Some medications are being made available in the form of prefilled syringes, and are anticipated to reduce medication errors significantly. The industry of prefilled syringes is projected to cross 5 billion used.⁷⁹

MANAGEMENT OF ERRONEOUS ADMINISTRATION OF MEDICATION

Medication errors in the anesthetic scenario can be associated with significant morbidity and mortality. Preparation of premed and anesthetic drugs with appropriate labeling prior to commencement of the case is the first step in anesthetic management. It follows that inaccurate labeling or identification of drugs, distraction and inexperience in a stressful operative environment can result in errors which can sometimes be fatal. Because some drug errors cannot be reversed, prevention is the best way to treat and minimize errors. Terminating services of an individual who commits an error has been commonly seen as effective prevention, though evidence really points to identification and management of system errors.¹² Methods for prevention of errors include outsourcing of prefilled syringes, or the cheaper option of preprinted label stickers which can be peeled and stuck onto vials or syringes. Unlabeled vials and syringes should be compulsorily discarded. VEINROM, ValiMed, and robotic preparation/dispensation of medications may gain popularity once they become more affordable.

CONCLUSION

While accepting that most errors are caused by unintentional mistakes, and are not always associated with bad outcomes, doctors need to be extremely vigilant to avoid these errors. With efforts at prevention, it is also important to report any near miss, so safety protocols can be further improved. This is important in the interest of patient safety as well as reduction in spiraling medicolegal costs. It follows that one of the principal stems in error prevention is education of anesthesiologists regarding the unique risks of their position. Being the only person responsible for prescribing, preparing, and administering drugs; the onus of checking and rechecking really falls on their shoulders. Beside this awareness and education, development of safer and error proof systems needs to be considered as a joint venture between 17anesthesiologists and their institutions. It appears that there continues to be underreporting of medical errors, which then mask the extent and effects of the problem. Cultural differences may contribute to difficulty in acceptance of errors. Finally, these measures, both at individual and organizational level, need to be accepted and implemented.

KEY POINTS

Error is defined as an act of omission or commission in planning or execution that contributes or could contribute to an unintended result.
Medical errors can be classified into active errors occurring around an incident, or latent errors that may not be immediately evident or visible.
Multiple complex factors based on interactions of human behavior with equipment and procedures contribute to causation of errors.
The human factors such as fatigue, long hours of work, stress, preoccupation or distraction as well as forgetfulness can contribute to accidents.
Anesthesiology is the most studied field in medicine for human factors in accident causation. It is also identified as significantly invested in strategies for patient safety by using technology for patient monitoring and implementation of safety guidelines.
Errors are not uniformly viewed, and like everything else, are subject to outcome bias or hindsight bias.
Most errors are potentially preventable complications which can be avoided by education, as well as addressing underlying systemic causes.
Medication errors have been documented as the seventh most common cause of mortality in hospitalized patients, with worst culprits being antibiotics and anesthetic agents.
Errors can occur during drawing up drugs and labeling phase, drug administration phase, or documentation phase.
Bar coding of medications, reconciliation of electronic medical records, large labels highlighting high-risk drugs, and similar measures have been proposed and adopted in many institutions with an aim of reducing the burden of error.

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Chapter Notes

Errors in Medicine: A Perioperative PerspectiveCHAPTER 1