INTRODUCTION

In recent years, health services have been increasingly concerned with medical errors. A number of initiatives related to patient safety have emerged, including the landmark 1999 report entitled “To err is human”: building a safer health system” by the Institute of Medicine (IOM) of the United States. According to the IOM, errors associated with health care cause between 44,000 and 98,000 deaths a year in American hospitals¹. This report revealed the number of errors and adverse events (AE) that occur in health services, harming patients, lengthening hospital stays, increasing social costs and even causing premature death².

According to the World Health Organization (WHO), safety means “reduction, to an accepTable limit, in the risk of unnecessary harm associated with health care”³. Safe drug use aims at reducing medication errors, which is divided into several stages with high risk of failure.

Medication error is defined as an avoidable event that leads or may potentially lead to the inadequate use of medication. Errors may be related to professional practice, the products used, procedures, communication problems, including prescription, labels, packaging, names, preparation and dispensation (the focus of the present study), distribution, administration, education, follow-up and medication use⁴. Despite the potential seriousness of these events, it is believed that many are under-reported⁵.

Antineoplastic drugs are considered potentially dangerous and errors derived from their use may cause permanent injury or even death⁷. Added to this is the fact that these drugs exhibit a low therapeutic index, that is, the toxic dose is very near the effective dose, representing a high risk of adverse events. Chemotherapy involves the simultaneous use of several adjuvant drugs aimed at producing a synergistic therapeutic effect with the least toxicity possible⁷.

Studies demonstrate that errors related to antineoplastic drugs occur at a rate of 1 to 4 in every 1000 drug prescriptions, affecting from 1 to 3% of oncological patients, both children and adults, at all stages of the drug dispensation process⁸.

The literature highlights many errors in the prescription and administration ^{9 10 11}, but there is little emphasis on this phase. The Institute for Safe Medication Practices (ISMP) recommends applying the risk management tool Failure Mode and Effects Analysis (FMEA) in order to minimize failures in the entire medication process¹².

This tool is used by the industry to proactively assess potential failures in a certain process^{13 14}. It has undergone several updates and is widely applied in different sectors such as the aerospace and automobile industries, among others. Healthcare Failure Mode and Effects Analysis (HFMEA) is a simplified form of Failure Mode and Effect Analysis FMEA) that has been adapted to health services. This makes it possible to proactively identify the vulnerabilities of health care systems. It is based on the concept that risk is not only related to the probability that failure will occur, but also the severity of its consequences^{13 14}. After identification and analysis of failure modes, their effects and causes, intervention priorities and recommendations are established in order to identify the changes needed to eliminate or reduce the risks of possible failures. The process is analyzed from start to finish by a group of specialists in the area assessed. There are currently few studies on FMEA or HFMEA in Brazil, particularly the analysis and prevention of risks associated with chemotherapy drugs, demonstrating a clear need to apply FMEA as prospective assessment of failure modes and their effects in the dispensation and preparation of chemotherapy drugs, corroborating towards better patient quality and safety.

Thus, the present study aimed at conducting a multimode analysis of failures and effects to prospectively identify the risks related to the preparation and dispensation of chemotherapy drugs in an outpatient unit of an oncology reference center.

MATERIALS AND METHODS

This is a descriptive study that applied failure mode and effect analysis (FMEA), conducted in an outpatient unit of a philanthropic oncology reference center, in Natal, Rio Grande do Norte state, Brazil. FMEA consists of eight stages: 1- identifying dangerous situations and assembling a team; 2- defining the process to be analyzed and describing it graphically; 3- applying a host of ideas in order to identify failure modes; 4- prioritizing failure modes and conducting risk analysis; 5- identifying potential causes of failure modes; 6- redesigning the process; 7- analyzing and testing the new process; and 8- devising interventions and indicators ¹⁵. In the present study, we report only on stages 1 to 6, which were feasible to analyze at the facility in question.

Stage 2: defining the process to be analyzed and describing it graphically

The medication process starts with a medical assessment of the patient, as well as the results of laboratory examinations to then evaluate the possible prescription or not of chemotherapy drugs. Next, the doctor enters a digital prescription into the computer and attaches a copy to the patient's medical chart. Patients are then referred to the chemotherapy administration sector, where they are registered, their dose noted and a drug label printed. Within this process, the subprocess medication “preparation and dispensation” was selected.

The flowchart of the medication preparation subprocess was created at the first meeting based on the knowledge of the team involved. This knowledge was essential, since it made it easy to identify the failure modes in each of the preparation and dispensation stages, involving pharmacy and nursing professionals (Figure 1).

Source: the authors

Figure 1. Description of the medication preparation and dispensation process 

Chemotherapy preparation and dispensation subprocess, Pharmacy assistant checks the nurse's digitized dose, Digitized dose separated and taken to the nursing department, Nurse checks the dose received against the digitized dose, Nurse prepares the saline solution, labels it and sends it to the pharmacist, Pharmacist separates the medication according to the laminar flow hood indicated for preparation, Pharmacist prepares/handles the medication, Nurse dispenses the prepared dose.

Stage 4: prioritizing failure modes and analyzing risks

The failure modes were grouped into a Table and the Risk Assessment Matrix was applied to determine the risk severity versus probability of occurrence.

The Risk Assessment Matrix result is obtained by multiplying the probability of failure (frequent, occasional, uncommon, remote) by the severity of its consequences (catastrophic, important, moderate, minor). Failure modes with values of eight or higher are failures with risk of occurrence where the potential causes should be identified. In order to decrease the subjectivity of each criterion in terms of the severity of the effect and probability of occurrence, the classification proposed by the Veteran Affairs National Center for Patient Safety (VA) was used (Table 1)¹⁶_.

Table 1: Criteria to classify the severity of failures analyzed with FMEA 

Source: DeRosier J, et al. ¹⁶ and adapted by the authors.

For failure modes with scores ≥ 8, the decision tree was applied for HFMEA (Figure 2), which considers two additional criteria: criticality (if the failure is essential to the process) and possibility of detection (if its emergence is obvious and can be changed in time)¹⁶. After the decision tree was applied, it was possible to determine which failure modes should proceed to the next stage. Based on the results obtained, a proposal of measures to improve risk prevention was sent to the technician in charge of the pharmacy.

Source: DeRosier J, et al. ¹⁶ and adapted by the authors

Figure 2. Decision tree for FMEA 

RESULTS

A total of 17 failure modes were identified in the medication preparation and dispensation phase (Table 2).

Table 2: Failure modes according to the prioritization matrix 

Source: the authors

Of the 17 failure modes, three obtained a value > 8 and were therefore analyzed with the decision tree for HFMEA: changing the output window of prepared medication, wrong calculation of intrathecal drug dose and wrong volume of aspirated medication. The failure mode “wrong drug volume aspirated during preparation” was interrupted by the decision tree, since it can be detected as it occurs. Thus, there are two potential failure modes that proceeded to the next FMEA stage, in order to propose improved measures and practices.

Stage 5: identifying the potential causes of failure modes

Several potential causes were identified by the team, showing possible failure hitherto not perceived, as described in Table 3.

Table 3: Potential causes of failure modes 

Source: the authors

With respect to the potential causes of failure modes related to “changing the output window of prepared medication” the possible causes are lack of attention, window labeling and knowledge of processes on the part of professionals. This failure could cause new drug administration in a prepared saline solution and an overdose, putting patients at risk, depending on the drug in question.

The failure mode “wrong calculation of intrathecal drug dose” could seriously harm the patient, and sometimes be fatal ¹⁸. The potential causes of this failure are a defective calculator, a change in drug presentation or work overload.

DISCUSSION

Applying the FMEA tool at the pharmacy unit made it possible to identify possible failure modes that were hitherto undetected, demonstrating potential vulnerabilities in the chemotherapy drug preparation and dispensation process.

According to the comprehensive review, the main risk factors identified for the occurrence of errors related to drug preparation are associated with psychological factors, such as work overload, factors related to the work environment and outdated health education¹⁹.

The excess workload o

f health professionals is one of the risk factors most cited as a trigger of stress and lack of attention, facilitating errors^{20 21}. Other studies also report overwork as a cause of failures ^{22 23}. Given the high number of drugs handled and the fact that many professionals work double shifts, it is recommended that the pharmacist be limited in the number of drugs handled at one time.

With respect to workplace-related failures, Brazilian guidelines stipulate that the medication preparation area must be well lit and ventilated, and that access be restricted to professionals directly involved in the process to minimize distractions²⁴. The physical infrastructure of the pharmacy where the study was held is adequate, well lit and equipped with physical barriers between the sectors, but there is a lack of labeling regarding the processes that are performed in each area.

Continuing education aims to share knowledge of the existing protocols in the sector with a maximum number of individuals involved in the chemotherapy medication process, thereby ensuring the quality of professional training at the institution. Health education is one of the tools that seeks to incorporate the team in a participative and dynamic way through classes, conversations or knowledge sharing. Among the limitations identified is the difficulty in gathering the entire team for all the scheduled meetings, due to their limited available time. The number of meetings may have restricted the possibility of conducting an in-depth investigation of other non-identified failure modes. Another difficulty is the consensus of the participants about the seriousness of the failures identified, where opinions varied considerably from one individual to another. This may be due to the length of experience of the workers or the circumstances of different occupations.

One of the FMEA limitations is the tendency to over or underestimate the seriousness of the failure, given it is a prospective possibility²⁵. This tendency was observed in our application of FMEA, where the failure modes scored far below the “expected” value when decided by consensus.

Another study limitation is the fact that it was conducted in a single pharmacy, specialized in chemotherapy, with specific local characteristics. As such, the results obtained may not be common to other pharmacies specialized in chemotherapy. The present study proposed to apply FMEA to identify prospective failure modes and suggest interventions. A future study will make it possible to assess the effectiveness of measures taken in relation to stages 7 and 8.

During this study, prospective analysis of the process allowed ample assessment of possible failure modes. The study demonstrated the need for risk management in institutions that prioritize quality care, a concern that is only now emerging in our context.

Thus, with the increasing search for quality and patient safety, FMEA should be considered a valid method for enhancing risk management, since it allows a prospective analysis of the chemotherapy medication process in the preparation and dispensation phase, with a view to identifying potential failures and their associated causes, in addition to devising strategies to correct these vulnerabilities. Moreover, the involvement of employees in the patient safety process encourages a culture of institutional safety and more adequate management of the work process, thereby improving the quality of care provided to the users of health services.

CONCLUSION

The present study aimed at conducting a multimode analysis of failures and effects to prospectively identify the risks related to the preparation and dispensation of chemotherapy drugs in an outpatient unit of an oncology reference center. Within the proposed context, the possible failure modes related to chemotherapy preparation and dispensation were identified, in addition to establishing the potential causes of these risks.

With respect to the local context, this study was important in identifying possible opportunities to improve the identification, preparation and dispensation of chemotherapy medication, via application of the FMEA instrument. These contributions will minimize the current risks to patients, in addition to providing the employees involved in the medication process with knowledge of possible failures and control strategies aimed at containing risks.