Assessing harm associated with retained surgical item: a 12-year experience in Hong Kong

Introduction

In Hong Kong, a sentinel event due to “retained instruments/material” [also known as retained surgical items (RSIs) and so-called in this paper henceforth] is any material object related to an operative or invasive procedure that is unintentionally left inside a patient (1). They can be associated with serious harm to patients including: readmission; second surgery to remove the item; sepsis or infection; fistula or small bowel obstruction; and visceral perforation (2). RSI have been designated as a Sentinel Event in a number of countries, including the US and Australia, due to their potential to cause harm to patients and because they are preventable (3). The list of ‘Sentinel Events’ (SE) in Hong Kong closely resembles the original Sentinel Events list from the Australian State of Victoria (4), and while the characteristics of SE are not defined in Hong Kong, in Victoria they are described as “infrequent serious adverse events that result in harm to patients and typically occur as a result of system or process issue” (4) (Table 1).

In Hong Kong, RSI are the most commonly reported SE (5). There has been no research on the harm associated with RSI in Hong Kong despite being a priority as a SE. SE may not result in patient harm but the frequency or extent to which patient harm occurs for RSI have never been quantified. This is important because all SE in Hong Kong require a Root Cause Analysis (RCA) investigation (6-8) which can be resource-intensive to undertake. If a significant proportion of RSI do not result in patient harm, the time and resources taken to perform these in-depth investigations could instead be redirected to higher impact improvement activities.

Policy background

The Hong Kong Hospital Authority (HA) introduced the ‘Sentinel Event Policy’ in 2007 (renamed the ‘Hospital Authority Sentinel & Serious Untoward Event Policy’ in 2010) (the Policy). RSI after surgery or interventional procedure was designated as Category 2 SE (6-8). The definition of this category has, however, changed since its introduction. Initially, Category 2 SE was defined as “retained instruments or other materials after surgery/interventional procedure requiring re-operation or further surgical procedure” (6). The need to re-operate or to perform further surgical procedure was removed for classification purposes during the policy revision in 2010 (7), and in 2015 the definition was further supplemented with “the potential for harm from the retained foreign object, or whether the object is removed after discovery is irrelevant to its designation as a Sentinel Event” (8) (Table 2). Therefore, over time the threshold for reporting retained surgical instruments has reduced.

Patient harm is documented in terms of the severity index (SI) (Table 3), which is a reporter-rated measurement of patient consequence applied to all incidents that is confirmed by local hospital Quality and Safety Departments. SI uses multiple metrics and may be ambiguous and easily influenced by the reporter’s perception of the incidents. Taking SI levels 2 and SI 3 as an example, incidents of SI 2 required minor treatment while those of SI 3 required simple treatment. Yet, the definitions of “minor” and “simple” treatment are not specified; for the same treatment, different reporters could interpret the level of treatment differently.

This study has three aims: firstly, to investigate the level of harm associated with RSI; secondly, to assess the utility of the current measure of harm, and thirdly, to determine the impact of two changes (in three periods) of broadening the measure’s definition over 12 years. We present this article in accordance with the STROBE reporting checklist (available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-106/rc).

Methods

Data source

As required by the Policy, the reporting of Category 2 SE, and the submission of RCA investigation reports are mandatory (6-8), and are conducted at the hospital level. In this retrospective cross-sectional study, executive summaries of all RCA reports arising from Category 2 SE—RSIs in Hong Kong since the implementation of the first SE policy were retrieved. The timeframe covered was 1 October 2007 to 30 September 2019.

Harm definition

The authors developed the RI-OST (Retained Instrument-Objective Scale of Treatment/level of care) that patients underwent as a result of the RSI. RI-OST was developed by the authors (A.P.M. and J.Y.M.C.) reviewing 175 Category 2 SEs for objective outcomes. Treatment actions were assessed as the most amenable to objective assessment based on the type of information in the RCA reports. The RI-OST was developed by the two authors reading the RCA reports together assessing treatment outcomes and iteratively agreeing on broad categories. Four categories resulted: (I) conservative management, whereby no further action was required, including removal of the surgical item (a typical example being a tiny metal fragment left inside the body following orthopaedic surgery); (II) removal of RSI without the need for an operation (e.g., removal of a central venous line guidewire that did not migrate, or a gauze pack left within the vaginal vault after delivery); (III) removal of RSI under local anaesthesia (LA) (e.g., removal of a gauze or drain left inside a deep wound); and (IV) removal of RSI under general anaesthesia (GA) (e.g., removal of retractors from the abdominal cavity). Systemic complications would necessitate surgical removal of the foreign body, and thus would automatically fall into RI-OST categories 3 or 4. Conservative treatment and non-operative removal were designated as “minor/insignificant consequence” and re-operation under LA and GA corresponding to “major/moderate consequence”.

All RCA reports arising from Category 2 SE from 1 October 2007 to 30 September 2019 were identified and their executive summaries reviewed. RSI events were subsequently allocated to the four categories of the RI-OST described above. The specialty departments involved, and the time taken to complete the RCA, which were fields in the report template, was identified and analysed during the review.

Study design

Aims 1 and 2

The authors extracted the level of patient harm as measured by the SI from each RCA report. The authors then rated each report on the RI-OST. The specialty department involved, as well as the number of man-hours required for the development of each RCA report, which covered the time spent on the entire investigation by the whole RCA panel, including preparation work, interviews, RCA panel’s discussion and report writing were noted.

Aim 3

To investigate the effect of the change in definitions on the harm of Category 2 SE reported, the RI-OST were analysed within three periods. The three periods correlate to the timing of the Policy definition changes and were: Period 1—1 October 2007 and 31 December 2009; Period 2—1 January 2010 and 30 June 2015; and Period 3—1 July 2015 and 30 September 2019 (Table 4).

Statistical analysis

The statistical analyses were all descriptive. For Aims 1 and 2, the ratings of the RCAs using the SI and RI-OST were descriptively compared against each other. For Aim 3, numbers and percentages of totals of incidents by the RI-OST by period were analysed and standardised to a 12-month period. All analyses were cross-tabulated in tables.

The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by Clinical Research Ethics Committee, Kowloon Central Cluster, which is the governing committee in research ethics of the HA Head Office (approval number: KC/KE-20-0235/ER-1). The committee approved a waiver of consent given the nature of the study, as it would not be feasible to obtain consent from all individual participants.

Results

There were 175 Category 2 SE reported between 1 October 2007 and 30 September 2019, and all reported events occurred in acute public hospitals, involving 14 different specialties. The specialty department with the highest number of Category 2 SE was Orthopaedics (n=58; 33%), followed by Surgery (n=34; 19%), Obstetrics and Gynaecology (O&G) (n=30; 17%) and Medicine (n=17; 10%). The other specialties all had less than 10 cases over the past 12 years and thus not discussed in detail (Figure 1).

Figure 1 Number of RSI sentinel events according to specialty departments. RSI, retained surgical item.

When SI was used to rate the level of harm, there were 8 cases with ‘X’ which represents an ‘indeterminate’ SI, which were excluded from the analysis.

Aims 1 and 2: SI against RI-OST as measurement of harm

There were significant discrepancies between measuring harms using SI and the RI-OST. Of the 167 RCA reports, there were differences in 38 (23%) (Table 5). There were 85 cases with minor/insignificant treatment levels measured by the RI-OST; of these 6% (n=5) were reported to have major/moderate consequences (i.e., levels 3 or 4) using SI. As for the 82 cases with Patient RI-OST major/moderate treatment levels, 40% (n=33) were reported to have minor/insignificant consequences (i.e., levels 1 or 2) using SI.

Among the 167 Category 2 SE studied, 60% (n=101) had complete documentation of the number of RCA panel members and the no. of hours spent on conducting the RCA. The average total hour per RCA was 25.8 hours.

With each change in definition of Category 2 SE in the Policy, the annual number of RSI SEs increased from 11 to 14 to 15 while the relative proportion of RSI in all SEs rose from 28% to 38% to 42% (Figure 2).

Figure 2 Annualized change in incidence of RSI over three periods. RSI, retained surgical item.

Aim 3: Effects of the change in Category 2 SE definitions on the harm of Category 2 SEs reported

In Period 1, contradictory to the definition in the Policy which re-operation to remove the RSI was necessary, 41% of the cases (n=11) had minor or insignificant harm. With each change in definition of Category 2 SE in the Policy, there was an increase in the percentage of Category 2 SE with minor or insignificant harm, from 43% in Period 2 (n=34) to 64% in Period 3 (n=40) (Figure 3).

Figure 3 Harm of RSI SEs for each period. RSI, retained surgical item; SE, sentinel event.

Discussion

The number of SE involving RSI in Hong Kong’s public healthcare system has attracted significant media attention in recent years (9,10). While the number of RSI SE might seem alarming, the actual harm on patients with these SE should be of greater focus. This study investigated the level of harm indicated by treatment level of 167 RSI SE across a 12-year period, since the implementation of the Hospital Authority Sentinel Event Policy in 2007. The definition of Category 2 SE when the SE Policy was first introduced in 2007 specified the need of re-operation or further surgical procedure. This requirement, however, was removed from the definition starting from the 2010 version of the Policy. There was an increase in proportion of RSI incidents with insignificant/minor harm after every policy review which broadened the definition of this SE category. Our findings on Category 2 SE captured between 2010 and 2019 after the first change in definition showed that more than half resulted in minimal harm.

The proportion of RSI incidents with insignificant or minor harm increased by 20% after the 2015 Policy review which added the supplementary note that the size and the harm that potentially arises are unrelated to the classification of Category 2 SE. The annual average number of RSI SEs in Period 3 was higher than Period 1, however the relative proportion of major-moderate harm SEs decreased from 56% and 57% in Periods 1 and 2, to 36% in Period 3. This resulted in resource-intensive RCA investigations being undertaken for a larger proportion of incidents with minor harm to patients, when these investigations largely should only be undertaken for more serious incidents.

Comparing the definition of SE involving RSI in Hong Kong with those of other countries, Hong Kong has a considerably broader definition. The Joint Commission’s SE definition in the US includes the phrase “death, permanent harm or severe temporary harm” as an inclusion criteria (11). The Australian Commission on Safety and Quality in Health Care’s SE definition includes the criteria “serious harm to, or the death of, a patient” (12). To align with international practices and to allocate more resources on investigating Category 2 SE with significant or extreme consequences, a component of significant harm could be re-introduced to the definition of Category 2 SE in HK.

This study examined the accuracy of using HA’s SI as an indication of patient harm. There was a discrepancy in the classification of nearly one-quarter of the RSI SE captured in the 12-year period compared to a classification based on treatment level-based measurement of harm. This could be due to ambiguity of definitions in the SI classifications, or oversight by the reporting staff and subsequently hospital Quality and Safety Departments. Among these cases, patient harm was more commonly underestimated than overestimated. Our finding that over 40% of SEs involving RSI between 2007 and 2009 did not require re-operation for removal despite the fact that re-operation was the criteria for classification of SE of this category, further supported that SI was not an accurate representation of the harm done on patients. The implications of discrepancies of SI compared to a treatment level-based measurement of harm also go beyond use of resources in incident investigations, creating measurement and benchmarking challenges, and could mislead health service managers in understanding and determining where and how to focus improvement efforts.

Adopting a treatment level-based measurement of harm such as the RI-OST rather than using SI may result in a more accurate measure of patient harm, as treatment level is a more objective measurement of patient harm when compared with SI definitions. Not only will the reported harm be more accurate due to reduced ambiguity, the reporting of the incident will also be easier as the measurement considers single instead of multiple parameters.

Implications

Findings of this study identified potential areas of improvements on incident classification and reporting in the organization. Firstly, the study identifies the misalignment in the local SE Policy definitions compared to international definitions where harm is considered, in particular for Category 2, which addresses RSI. Second, the study also identified that the allocation of resources for incident investigation may not been aligned to severity of outcome. It has also been identified that the governance of SE classification may have gaps, leading to data inaccuracies that can contribute to an unintended focus on low consequence risks. Findings from this study can enhance our understanding on the current situation of RSI in Hong Kong. This knowledge can assist healthcare managers with formulating policies to better manage incidents involving RSI and to better allocate resources on investigating such incidents.

The authors suggest a number of recommendations. Firstly, to align the definitions of SE with current international definitions where harm is considered. Secondly to review the methodology for incident classification and reporting in the organization, including to consider after further validation, adopting a treatment level-based measurement of harm rather than using SI for RSI. Thirdly, to reallocate resources on performing incident investigations using the resource intensive RCA only for incidents with patient harm of major/moderate consequence. Fourthly, to monitor pattern and trends for more minor incidents and carry out aggregated analysis (13). Finally, staff should be further trained on SE definitions, the conducting of RCA investigations, including report writing, and to review the mechanism to ensure patient safety data is accurately documented.

One of the strengths of the study is that we analysed the population of RCA reports in the relevant time period, and not a sample, enabling a comprehensive and representative analysis to be undertaken. At the same time, there were a number of limitations. Firstly, the study relied on the interpretation of others’ coding from the reports, and inter-rater reliability was not performed. However, as outcomes were explicit and well described, this limitation could be mitigated. Secondly, RCA executive summaries were used as the data source rather than full reports, restricting some level of detail, but for the purposes of this study, there was sufficient information in the executive summary to understand the level of harm of each event.

Conclusions

This study investigated the level of harm associated with RSI, assessed the accuracy of the SI as a measure of harm, and measured the change in level of harm associated with a change in definition of SE involving RSI in public hospitals in Hong Kong. Findings show that the majority of RSI incidents captured had insignificant or minor harm, and there was an increase in proportion of RSI incidents with insignificant/minor harm after the latest policy review. The authors suggest a number of recommendations to align with current international definitions of SE, improve allocation of resources for higher consequence risks, and improve patient safety data accuracy.

Acknowledgments

The authors would like to thank all the clinicians and the Quality and Safety teams in all the Hong Kong Hospital Authority hospitals for continuing to support the investigations of Sentinel Events despite the significant workload. Appreciation also goes to the Patient Safety and Risk Management team at the Head Office for the support of this project.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-106/rc

Data Sharing Statement: Available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-106/dss

Peer Review File: Available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-106/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-106/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by Clinical Research Ethics Committee, Kowloon Central Cluster, which is the governing committee in research ethics of the HA Head Office (approval number: KC/KE-20-0235/ER-1). The committee approved a waiver of consent given the nature of the study, as it would not be feasible to obtain consent from all individual participants.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Fencl JL. Guideline Implementation: Prevention of Retained Surgical Items. AORN J 2016;104:37-48. [Crossref] [PubMed]
2. Berger PS, Sanders G. Objects retained during surgery: human diligence meets systems solutions. Patient Saf Qual in Healthcare 2008;5.
3. Hibbert PD, Thomas MJW, Deakin A, et al. A qualitative content analysis of retained surgical items: learning from root cause analysis investigations. Int J Qual Health Care 2020;32:184-9. [Crossref] [PubMed]
4. Safer Care Victoria. Sentinel events annual report 2016-17. Safer Care Victoria, 2018. Available online: https://www.bettersafercare.vic.gov.au/sites/default/files/2018-08/Sentinel%20events%20annual%20report%202016-17%20FINAL.pdf (accessed 6 October 2022).
5. Hong Kong Hospital Authority. Annual Report on Sentinel and Serious Untoward Events (October 2019-September 2020). Hong Kong Hospital Authority, 2021. Available online: https://www.ha.org.hk/haho/ho/psrm/T_SESUE1920.pdf (accessed 6 October 2022).
6. Hong Kong Hospital Authority, HA Sentinel Event Policy. Hong Kong Hospital Authority, 2007.
7. Hong Kong Hospital Authority, Sentinel and Serious Untoward Event Policy. Hong Kong Hospital Authority, 2010.
8. Hong Kong Hospital Authority, Sentinel Event and Serious Untoward Event Policy. Hong Kong Hospital Authority, 2015.
9. Searchlight. Poor governance in Hong Kong led to terrifying medical blunders (in Chinese). Oriental Daily. 19 April 2019. Available online: https://orientaldaily.on.cc/cnt/news/20190419/00176_078.html (accessed 6 October 2022).
10. Searchlight. Ventricular catheter carelessly retained following surgery at public hospital (in Chinese). Oriental Daily. 25 January 2019:. Available online: https://orientaldaily.on.cc/cnt/news/20190125/00176_053.html (accessed 6 October 2022).
11. Joint Commission. Sentinel Events. Available online: https://www.jointcommission.org/-/media/tjc/documents/resources/patient-safety-topics/sentinel-event/cambhc_21_se_all_current.pdf (2021, accessed 6 October 2022).
12. Australian Commission on Safety and Quality in Health Care. Australian sentinel event list (version 2). Available online: https://www.safetyandquality.gov.au/sites/default/files/migrated/Final-Australian-sentinel-events-list-version-2-December-2018.docx (2018, accessed 6 October 2022).
13. Hibbert PD, Healey F, Lamont T, et al. Patient safety's missing link: using clinical expertise to recognize, respond to and reduce risks at a population level. Int J Qual Health Care 2016;28:114-21. [Crossref] [PubMed]