| Literature DB >> 31399897 |
Ernesto Iadanza1, Valentina Gonnelli2, Francesca Satta3, Monica Gherardelli2.
Abstract
Maintenance is a crucial subject in medical equipment life cycle management. Evidence-based maintenance consists of the continuous performance monitoring of equipment, starting from the evidence-the current state in terms of failure history-and improvement of its effectiveness by making the required changes. This process is very important for optimizing the use and allocation of the available resources by clinical engineering departments. Medical equipment maintenance is composed of two basic activities: scheduled maintenance and corrective maintenance. Both are needed for the management of the entire set of medical equipment in a hospital. Because the classification of maintenance service work orders reveals specific issues related to frequent problems and failures, specific codes have been applied to classify the corrective and scheduled maintenance work orders at Careggi University Hospital (Florence, Italy). In this study, a novel set of key performance indicators is also proposed for evaluating medical equipment maintenance performance. The purpose of this research is to combine these two evidence-based methods to assess every aspect of the maintenance process and provide an objective and standardized approach that will support and enhance clinical engineering activities. Starting from the evidence (i.e. failures), the results show that the combination of these two methods can provide a periodical cross-analysis of maintenance performance that indicates the most appropriate procedures. Graphical abstract The left side shows a block diagram of the process needed to calculate the proposed set of KPIs, starting from technological, organizational and financial data. On the upper right it is shown an example of scheduled maintenance analysis for a specific class of equipment (legend in the article body). The bottom right part shows how the KPIs can be implemented in a business intelligence dashboard.Entities:
Keywords: Clinical engineering; Evidence-based maintenance; Health technology management; Key performance indicators; Medical equipment
Mesh:
Year: 2019 PMID: 31399897 PMCID: PMC6791913 DOI: 10.1007/s11517-019-02021-x
Source DB: PubMed Journal: Med Biol Eng Comput ISSN: 0140-0118 Impact factor: 2.602
Analysed data
| Departments | Rooms | Beds | Wards | |||
| Operating rooms | 40 | 9 | ||||
| Interventional | 5 | 5 | ||||
| Intensive care | 165 | 10 | ||||
| Device type | TOT Units (U&oU) | TOT CM WO | TOT | OR&IC | OR&IC | OR&IC SM WO |
| SM WO | Units | CM WO | ||||
| Anaesthesia Machine | 162 | 802 | 491 | 109 | 593 | 444 |
| Aspirator | 377 | 160 | 287 | 43 | 20 | 42 |
| Ceiling mounted unit | 319 | 284 | 522 | 214 | 165 | 386 |
| Central monitoring | 63 | 212 | 147 | 33 | 114 | 87 |
| Defibrillator | 410 | 1463 | 2036 | 128 | 438 | 709 |
| Electrocardiograph | 356 | 1384 | 947 | 57 | 155 | 148 |
| Electrosurgical | 205 | 287 | 408 | 148 | 181 | 342 |
| Monitor | 900 | 1294 | 3337 | 487 | 547 | 1794 |
| Oximeter | 613 | 557 | 1120 | 154 | 110 | 297 |
| Surgical lamp | 354 | 411 | 1222 | 225 | 239 | 987 |
| Surgical table | 93 | 520 | 382 | 70 | 349 | 211 |
| Telemetry | 104 | 99 | 142 | 27 | 59 | 51 |
| Ventilator | 203 | 796 | 831 | 155 | 611 | 748 |
| Total analysed data | 4159 | 8269 | 11,872 | 1850 | 3581 | 6246 |
Fig. 1The left side shows a block diagram of the process needed to calculate the proposed set of KPIs, starting from technological, organizational and financial data. On the upper right, an example of scheduled maintenance analysis for a specific class of equipment is shown (legend in the article body). The bottom right part shows how the KPIs can be implemented in a business intelligence dashboard
Failure codes
| Code | Description | CM/SM |
|---|---|---|
| NPF | No problem found | Both |
| BATT | Battery failure | Both |
| ACC | Accessory failure (including supplies) | Both |
| NET | Failure related to network | CM |
| USE | Failure induced by use (i.e. abuse, accident, environment conditions) | CM |
| UPF | Unpreventable failure caused by normal wear and tear | CM |
| PPF | Predictable and preventable failure | CM |
| SIF | Induced by service (i.e. caused by a technical intervention not properly completed or premature failures of a part just replaced) | CM |
| EF | Evident failure (i.e. evident to user but not reported) | SM |
| PF | Potential failure (i.e. in process of occurring) | SM |
| HF | Hidden failure (i.e. not detectable by the user unless special test or measurement equipment) | SM |
Key performance indicators
| Index | KPI type | Definition | Rationale | Involved activity | |||
|---|---|---|---|---|---|---|---|
| Corrective Maintenance CM | Scheduled Maintenance SM | Internal Maintenance IM | External Maintenance EM | ||||
KPI 1 Downtime (%) (non-availability time) |
|
with: | Operational efficiency, actual equipment availability compared with requirements. | X | X | ||
KPI 2 Uptime (%) (availability time) |
|
with: | Operational efficiency, actual equipment availability compared with requirements. | X | |||
KPI 3 MTTR (mean time to restoration) |
|
| Parameter of reliability, availability. | X | |||
KPI 4 MTBF (mean time between failures) |
|
| Parameter of reliability, availability. | X | |||
KPI 5 Class failure ratio (fails per class) |
|
| Failure rate of each class of equipment | X | |||
KPI 6 Global failure rate (defectiveness) |
|
| Fault occurrences related to the number of devices | X | |||
KPI 7 AFR: age failure rate |
|
Age classes: 0–2 years, 3–5 years, 6–9 years, ≥10 years | Device obsolescence | X | |||
KPI 8 “Negligent” actions (%) |
| Operational performance of maintenance process | X | ||||
KPI 9 “1 day” actions |
|
| Operational performance of maintenance process | X | |||
KPI 10 SM with failure (%) |
|
| Scheduled maintenance intervention with fault occurred | X | |||
KPI 11 SM coverage rate (scheduled maintenance) |
|
SM coverage rate | Scheduled Maintenance conformity to the requirements | X | |||
KPI 12 No problem found (fake faults) (%) |
|
| No fault found during the corrective maintenance work order | X | |||
KPI 13 No. devices per technician (internal) |
|
| Maintenance workload | X | X | ||
KPI 14
|
| Working hours spent on corrective maintenance vs working hours spent on scheduled maintenance | Maintenance-workload comparison between corrective and scheduled maintenance | X | X | ||
KPI 15 COSR (cost of service ratio |
|
| Maintenance service: financial performance (cost-effectiveness). | X | X | X | X |
KPI 16 External maintenance Cost (% with respect to total maintenance cost) |
|
where external maintenance cost = scheduled and corrective external maintenance costs | Impact of external maintenance on the total cost of the maintenance service | X | |||
KPI 17 Internal maintenance cost (% with respect to total maintenance cost) |
|
where internal maintenance cost = scheduled and corrective internal maintenance costs | Impact of internal maintenance on the total cost of the maintenance service | X | |||
KPI 18 Corrective maintenance cost (CM) (% with respect to total maintenance cost) |
|
where corrective maintenance cost = internal CM cost + external CM cost | Maintenance type: impact of corrective maintenance on the total cost of the maintenance service. | X | |||
KPI 19 Scheduled maintenance cost (SM) (% with respect to total maintenance cost) |
| Maintenance type: impact of scheduled maintenance on the total cost of the maintenance service. | X | ||||
KPI 20 Cost of spare parts (+ consumables) (% with respect to total maintenance cost) |
|
| Maintenance: Spare Parts and consumables. | X | X | X | X |
Fig. 2CM and SM failure distributions related to surgical tables, telemetry equipment, electro-surgery units and defibrillators in different years of the considered period
Technical KPIs
| Equipment class | Technical KPIs | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| KPI 1 | KPI 2 | KPI 3 | KPI 4 | KPI 5 | KPI 6 | KPI 7 | ||||
| Mean 5Y ± SD | Mean 5Y ± SD | (days) | (months) | Mean 5Y ± SD | Mean 5Y ± SD | 0–2 years | 2–5 years | 5–10 years | > 10 years | |
| CMO | 0.62% ± 0.36% | 99.38% ± 0.36% | 2.68 | 14.10 | 3.13 ± 0.89 | 0.87 ± 0.26 | 0.5 ± 0.5 | 0.7 ± 0.2 | 1.3 ± 0.4 | 0.1 ± 0.2 |
| TOP | 2.74% ± 0.69% | 97.26% ± 0.69% | 4.70 | 1.91 | 9.59 ± 2.52 | 1.35 ± 0.36 | 1.0 ± 0.4 | 1.9 ± 1.3 | 3.2 ± 1.0 | 1.3 ± 0.3 |
| UTC | 0.52% ± 0.27% | 99.48% ± 0.27% | 3.05 | 15.26 | 1.67 ± 0.48 | 0.64 ± 0.12 | 0.0 ± 0.0 | 0.6 ± 0.6 | 0.3 ± 0.4 | 0.0 ± 0.0 |
| ANS | 2.14% ± 0.61% | 97.86% ± 0.61% | 3.02 | 1.74 | 16.59 ± 1.92 | 1.45 ± 0.18 | 1.2 ± 0.7 | 1.9 ± 0.7 | 1.9 ± 0.5 | 1.1 ± 0.2 |
| ELB | 0.49% ± 0.30% | 99.51% ± 0.30% | 2.59 | 6.22 | 5.14 ± 1.49 | 0.41 ± 0.07 | 0.2 ± 0.1 | 0.4 ± 0.1 | 0.6 ± 0.2 | 0.8 ± 0.5 |
| VPO | 0.98% ± 0.4% | 99.02% ± 0.40% | 3.09 | 9.04 | 17.10 ± 1.83 | 1.07 ± 0.12 | 0.6 ± 0.4 | 1.4 ± 0.8 | 1.8 ± 0.5 | 1.1 ± 0.1 |
| ACH | 0.13% ± 0.16% | 99.87% ± 0.16% | 2.30 | 20.38 | 0.58 ± 0.42 | 0.12 ± 0.06 | 0.2 ± 0.2 | 0.2 ± 0.3 | 0.0 ± 0.1 | 0.2 ± 0.2 |
| ECG | 0.54% ± 0.33% | 99.46% ± 0.33% | 2.85 | 11.74 | 4.37 ± 1.54 | 0.53 ± 0.16 | 0.9 ± 0.5 | 0.9 ± 0.9 | 0.5 ± 0.3 | 0.5 ± 0.1 |
| LSC | 0.64% ± 0.44% | 99.36% ± 0.44% | 4.24 | 8.81 | 6.63 ± 2.54 | 0.30 ± 0.13 | 0.0 ± 0.1 | 0.5 ± 0.4 | 0.3 ± 0.1 | 0.5 ± 0.1 |
| DEF | 0.47% ± 0.36% | 99.53% ± 0.36% | 1.71 | 12.63 | 12.19 ± 2.30 | 0.96 ± 0.25 | 0.2 ± 0.1 | 0.4 ± 0.4 | 1.3 ± 0.3 | 1.2 ± 0.5 |
| PSO | 0.21% ± 0.12% | 99.79% ± 0.12% | 2.41 | 15.43 | 4.55 ± 1.59 | 0.16 ± 0.05 | 0.1 ± 0.1 | 0.3 ± 0.2 | 0.1 ± 0.1 | 0.2 ± 0.0 |
| OOR | 0.13% ± 0.08% | 99.87% ± 0.08% | 1.83 | 34.56 | 3.13 ± 1.18 | 0.20 ± 0.06 | 0.1 ± 0.1 | 0.3 ± 0.1 | 0.2 ± 0.1 | 0.1 ± 0.1 |
| MON | 0.31% ± 0.05% | 99.69% ± 0.05% | 3.73 | 38.04 | 15.33 ± 1.21 | 0.29 ± 0.04 | 0.1 ± 0.1 | 0.7 ± 0.6 | 0.5 ± 0.1 | 0.3 ± 0.1 |
Distribution of the equipment in age classes
| Age classes (mean no. of units for each age class) | ||||
|---|---|---|---|---|
| Equipment class | 0–2 years | 2–5 years | 5–10 years | > 10 years |
| CMO | 28.49% ± 16.48% | 31.28% ± 20.84% | 31.33% ± 13.90% | 8.90% ± 4.22% |
| TOP | 32.77% ± 12.76% | 13.64% ± 14.79% | 11.64% ± 2.86% | 41.94% ± 5.55% |
| UTC | 0.00% ± 0.00% | 38.00% ± 35.64% | 38.74% ± 45.63% | 23.26% ± 13.10% |
| ANS | 26.43% ± 14.49% | 25.33% ± 6.98% | 19.32% ± 3.48% | 28.92% ±6.77% |
| ELB | 24.74% ± 3.72% | 24.51% ± 4.55% | 19.12% ± 5.58% | 31.63% ± 4.11% |
| VPO | 10.78% ± 5.63% | 23.37% ± 18.27% | 23.93% ± 11.09% | 41.92% ± 3.14% |
| ACH | 9.95% ± 6.01% | 5.13% ± 5.40% | 15.17% ± 6.93% | 69.75% ± 6.53% |
| ECG | 9.96% ± 8.23% | 10.05% ± 7.45% | 21.03% ± 3.26% | 58.96% ± 6.66% |
| LSC | 33.97% ± 21.25% | 20.38% ± 20.73% | 12.75% ± 5.17% | 32.90% ± 3.21% |
| DEF | 10.63% ± 4.91% | 13.72% ± 8.91% | 33.67% ± 4.65% | 41.98% ± 6.04% |
| PSO | 42.34% ± 29.29% | 25.64% ± 28.00% | 10.01% ± 2.47% | 22.00% ± 0.90% |
| OOR | 23.38% ± 9.96% | 28.21% ± 12.41% | 27.20% ± 9.96% | 21.21% ± 5.59% |
| MON | 33.02% ± 20.56% | 25.81% ± 17.47% | 22.01% ± 5.57% | 19.16% ± 2.93% |
Organizational KPIs
| Organizational KPI | |||||
|
| |||||
|
|
“Negligent” actions (%) |
“1 day” actions |
SM with failure (%) |
SM coverage rate |
No problem found (%) |
| Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | |
| CMO | 7.51% ± 10.52% | 42.25 ± 17.41 | 1.00% ± 2.24% | 0.67 ± 0.07 | 16.97% ± 5.73% |
| TOP | 10.64% ± 6.63% | 22.35 ± 5.97 | 1.83% ± 3.04% | 0.84 ± 0.30 | 14.05% ± 4.73% |
| UTC | 55.63% ± 12.48% | 9.14 ± 11.72 | 0.00% ± 0.00% | 0.56 ± 0.31 | 4.40% ± 4.02% |
| ANS | 4.39% ± 4.84% | 45.05 ± 9.19 | 1.82% ± 1.31% | 1.09 ± 0.15 | 26.12% ± 4.93% |
| ELB | 5.25% ± 4.21% | 45.83 ± 24.69 | 1.00% ± 2.24% | 0.77 ± 0.15 | 26.51% ± 9.97% |
| VPO | 7.35% ± 3.74% | 49.65 ± 11.27 | 0.87% ± 0.84% | 1.31 ± 0.21 | 20.18% ± 2.92% |
| ACH | 0.00% ± 0.00% | 58.83 ± 25.71 | 0.00% ± 0.00% | 0.30 ± 0.26 | 38.00% ± 41.47% |
| ECG | 2.78% ± 2.89% | 47.23 ± 19.52 | 0.83% ± 1.86% | 0.51 ± 0.25 | 19.85% ± 6.42% |
| LSC | 4.21% ± 1.39% | 51.61 ± 15.00 | 1.54% ± 1.84% | 1.18 ± 0.51 | 13.03% ± 9.50% |
| DEF | 3.81% ± 2.93% | 64.49 ± 21.66 | 4.17% ± 3.85% | 1.56 ± 0.64 | 12.73% ± 2.49% |
| PSO | 5.84% ± 2.32% | 39.44 ± 7.99 | 1.19% ± 2.00% | 0.38 ± 0.38 | 21.27% ± 9.35% |
| OOR | 2.43% ± 3.33% | 46.87 ± 27.29 | 4.32% ± 5.44% | 0.54 ± 0.16 | 5.67% ± 1.92% |
| MON | 12.91% ± 4.29% | 29.08 ± 7.30 | 1.79% ± 1.42% | 0.94 ± 0.28 | 22.53% ± 7.41% |
| b | |||||
|
|
No. of devices per technician |
Time cost of the workforce | |||
|
| (h) | ||||
| Internal maintenance | Service | Internal maintenance | Service | ||
|
| 221 | 137 | 5412.50 | 906.35 | |
|
| 221 | 82 | 2247.70 | 348.90 | |
Financial KPIs
| Equipment class | Financial KPI | |||||
|---|---|---|---|---|---|---|
| KPI 15 COSR (cost of service ratio = global maintenance to acquisition cost) (%) | KPI 16 External maintenance cost (% with respect to total maintenance cost) | KPI 17 Internal maintenance cost (% with respect to total maintenance cost) | KPI 18 Corrective maintenance cost (CM) (% with respect to total maintenance cost) | KPI 19 Scheduled maintenance cost (SM) (% with respect to total maintenance cost) | KPI 20 Cost of spare parts (+ consumables) (% with respect to total maintenance cost) | |
| Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | Mean 5Y ± SD | |
| CMO | 2.31% ± 0.37% | 98.71% ± 0.41% | 1.19% ± 0.51% | 65.02% ± 0.48% | 34.88% ± 0.55% | 0.10% ± 0.13% |
| TOP | 2.32% ± 0.20% | 63.52% ± 14.44% | 2.55% ± 1.04% | 94.61% ± 3.06% | 5.39% ± 3.06% | 33.93% ± 13.72% |
| UTC | 2.99% ± 1.56% | 65.61 ± 41.17% | 34.39% ± 41.17% | 59.15% ± 1.91% | 31.85% ± 1.03% | 9.00% ± 2.94% |
| ANS | 5.30% ± 0.84% | 91.00% ± 2.94% | –* | 73.91% ± 16.13% | 17.44% ± 9.93% | 6.79% ± 8.04% |
| ELB | 1.45% ± 0.81% | 51.90% ± 0.82% | 41.31% ± 15.18% | 58.83% ± 2.87% | 33.02% ± 2.61% | 8.87% ± 4.53% |
| VPO | 8.48% ± 0.35% | 91.02% ± 4.62% | 0.14% ± 0.19% | 63.33% ± 26.73% | 31.96% ± 26.41% | 4.16% ± 7.55% |
| ACH | 2.30% ± 2.04% | 95.30% ± 7.55% | –* | 56.73% ± 9.92% | 29.42% ± 5.11% | 13.77% ± 14.70% |
| ECG | 2.56% ± 0.40% | 85.03% ± 15.91% | 1.20% ± 0.97% | 42.13% ± 16.86% | 28.14% ± 12.46% | 29.73% ± 13.94% |
| LSC | 2.44% ± 0.87% | 4.33% ± 4.53% | 65.94% ± 14.12% | 27.55% ± 6.39% | 10.30% ± 3.18% | 62.46% ± 8.25% |
| DEF | 1.60% ± 0.71% | 37.85% ± 8.25% | –* | 76.96% ± 8.13% | 18.05% ± 9.16% | 4.96% ± 2.58% |
| PSO | 0.68% ± 0.40% | 52.14% ± 8.53% | 42.87% ± 8.54% | 46.76% ± 26.46% | 16.09% ± 7.60% | 34.82% ± 27.02% |
| OOR | 4.33% ± 2.49% | 20.56% ± 33.76% | 43.29% ± 22.53% | 64.78% ± 1.32% | 29.42% ± 4.37% | 1.63% ± 0.96% |
| MON | 3.61% ± 0.81% | 96.36% ± 1.68% | 2.00% ± 0.83% | 65.02% ± 0.48% | 34.88% ± 0.55% | 0.10% ± 0.13% |
*Fully external maintenance
Fig. 3Surgery table: uptime pattern with (red-dashed line) and without (purple line) negligent maintenance service
Fig. 4Surgery table: MTTR pattern with (red-dashed line) and without (purple line) negligent maintenance service
SM coverage rate
| Equipment class | KPI 11–SM coverage rate | ||||
|---|---|---|---|---|---|
| 2012 | 2013 | 2014 | 2015 | 2016 | |
| CMO | 0.71 | 0.59 | 0.67 | 0.63 | 0.77 |
| TOP | 1.10 | 0.43 | 0.69 | 0.87 | 1.14 |
| UTC | 0.50 | 0.95 | 0.40 | 0.16 | 0.79 |
| ANS | 1.01 | 0.99 | 0.95 | 1.30 | 1.18 |
| ELB | 0.87 | 0.80 | 0.93 | 0.57 | 0.68 |
| VPO | 1.14 | 1.35 | 1.30 | 1.11 | 1.63 |
| ACH | 0.05 | 0.23 | 0.38 | 0.14 | 0.71 |
| ECG | 0.53 | 0.61 | 0.58 | 0.40 | 0.45 |
| LSC | 0.48 | 1.05 | 1.32 | 1.17 | 1.89 |
| DEF | 0.97 | 1.56 | 1.48 | 1.17 | 2.63 |
| PSO | 0.30 | 0.25 | 0.32 | 0.37 | 0.68 |
| OOR | 0.44 | 0.73 | 0.32 | 0.56 | 0.65 |
| MON | 0.71 | 0.61 | 0.99 | 1.13 | 1.26 |