A comprehensive fuzzy risk-based maintenance framework for prioritization of medical devices

Highlights

• A method to select the best maintenance strategy for critical devices is proposed.

• The method proposes a risk-based framework including experts’ opinions.

• The proposed approach handles both qualitative and quantitative data.

• Existing criteria related to prioritization of medical devices have been revisited.

• New relevant criteria have been defined.

Abstract

Medical equipment such as infant incubator, infusion pump, CT scanner, etc. should be maintained properly to meet adequate standards of reliability in healthcare services. This paper proposes a new comprehensive risk-based prioritization framework for selecting the best maintenance strategy. The framework encompasses three steps. In the first step, a fuzzy failure modes and effects analysis (FFMEA) method is applied by considering several risk assessment factors. In the second step, seven miscellaneous dimensions such as use-related hazards, age, and utilization are applied to consider all aspects of hazards and risks in prioritization of medical devices. Finally, a simple method is introduced in the third step in order to find the most suitable maintenance strategy for each device according to the scores produced by the previous steps. A numerical example illustrates the proposed approach and shows that, through the method introduced in this paper, managers can easily classify medical devices for maintenance activities according to their criticality scores. Implementation of this framework could increase the availability of high risk machines in healthcare industries. Moreover, this framework can be applied in other critical industries such as aviation by modifying some criteria and dimensions.

Introduction

Nowadays, safety of medical device and the hazards associated with utilization of them is one of the critical issues for healthcare organizations across the world [1]. Medical devices are instruments or machines that are used to diagnosis, monitor, treat, or prevent disease or other conditions. Degradation in the performance of critical medical devices and inadequately maintained medical equipment create an unacceptable risk of patient injury. In addition, there are risks of injury to clinical staff from simple, direct hazards, such as accidental contact with electrified parts or from mechanical failures within the device [3], for example defects in ultrasound machines, defective artificial cardiac valves, leakage of insulin pumps [4], and high number of errors in CT scans which leads to patients receiving 10 times the intended dose of radiation in some cases. Thus, the maintenance of medical devices is fundamental and it calls for an effective and efficient framework to prioritize medical devices for maintenance activities based on key criteria and choose the best maintenance policy for each device.

Clinical engineering departments in hospitals have been developing programs such as Medical Equipment Management Program (MEMP) to reduce risks associated to medical devices and to promote the safety of medical devices in support of patient care. Some risk based MEMP methods have been presented for assessment of devices and are currently in use. These models consider risk in terms of maintenance requirements of medical device, function of medical device, and physical harm/risk. However, other important criteria such as the number of patients served, economic loss, mean time to repair (MTTR), and use-related hazards, among others are overlooked. Rice [5] in his paper mentions that, “although these methods do reduce risks, they are not near optimal”. Besides, in most of the proposed models equal risk levels are assigned to similar devices and the operational and environmental conditions and independently of the hospital's mission statement are overlooked. This could lead to misclassifying devices, such as steam sterilizers, as low risk [6].

This paper presents a novel fuzzy multi-criteria decision making (FMCDM) approach to the medical device prioritization problem within a risk-based maintenance (RBM) framework. This comprehensive approach first prioritizes medical devices based on their criticality and then propose a diagram for selecting appropriate maintenance strategy in healthcare organizations. The two objectives of this research are (1) to revisit and reassess the major criteria and sub criteria that can affect medical devices risk scores, and (2) to propose a three steps approach for clinical engineers to prioritize medical devices and select the best maintenance strategy for them. The first step consists in applying FFMEA method to calculate the risk priority index (RPI_D) for each device. In the proposed FFMEA model, three criteria – severity (S), occurrence (O) and detection (D) – and eight sub-criteria have been considered. In the second step, seven miscellaneous dimensions are applied and total intensity (TI) score is calculated based on weighted sum of seven miscellaneous dimensions in order to take into account other aspects of hazards as well as S, O and D. Finally, in the third step, a maintenance planning diagram is proposed according to the scores produced by the previous steps. The proposed approach is illustrated by an academic example including five medical equipment.

The rest of this paper is organized as follows. Section 2 draws a literature review on the existing approaches to the medical device prioritization problem. Section 3 describes the proposed approach, while Section 4 illustrates its application on an academic numerical example. Conclusions and directions for future research are presented in Section 5.