https://orcid.org/0000-0002-8617-1120
Figures
Abstract
Background
To prevent recurrence of medical accidents, the Medical Accident Investigating System was implemented in October 2015 by the Japan Medical Safety Research Organization (Medsafe Japan) to target deaths from medical care that were unforeseen by the administrator. Medsafe Japan analyzed the 10 cases of central venous catheterization-related deaths reported in the system and published recommendations in March 2017. However, the particular emphasis for the prevention of central venous catheterization-related deaths is unclear.
Methods
This study aimed to identify the recommendation points that should be emphasized to prevent recurrence of central venous catheterization-related deaths. We assessed central venous catheterization in 8530 closed-claim cases between January 2002 and December 2016 covered by the medical insurer Sompo-Japan. Moreover, we compared central venous catheterization-related death in closed-claim cases with death in reported cases.
Results
The background, error type, anatomic insertion site, and fatal complication data were evaluated for 37 closed-claim cases, of which 12 (32.4%) were death cases. Of the 12 closed-claim cases and 10 reported cases, 9 (75.0%) closed-claim cases and 9 (90.0%) reported cases were related to vascular access. Among these, 5 closed-claim cases (41.7%) and 7 reported cases (77.8%) were related to internal jugular vein catheterization (p = 0.28). Coagulopathy was observed in 3 (60.0%) of 5 closed-claim cases and 6 (85.7%) of 7 reported cases.
Citation: Otaki Y, Fujishiro N, Oyama Y, Hata N, Kato D, Kawachi S (2022) The risk of fatal bleeding complications in jugular catheterization in patients with coagulopathy: A retrospective analysis of death cases in closed claims and the Medical Accident Investigating System in Japan. PLoS ONE 17(1): e0261636. https://doi.org/10.1371/journal.pone.0261636
Editor: Rudolf Kirchmair, Medical University Innsbruck, AUSTRIA
Received: August 25, 2021; Accepted: December 6, 2021; Published: January 13, 2022
Copyright: © 2022 Otaki et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the paper. The original text data (Japanese) are saved in the insurance company (Sompo Japan). Researchers need to contact the author, Yasuhiro Otaki (y-otaki@med.teikyo-u.ac.jp) or non-author, Tatsuji Katsuki (tkatsuki2@sompo-japan.co.jp), the person in charge of Sompo-Japan regarding Data Availability statement in the article, in order to access the data. Prior to that, the researchers need to gain approval from the ethics committee of their institutions.
Funding: YO received the funding for this work from the Japan Society for the Promotion of Science (JSPS) KAKENHI (grant number 18KT0099 and 19K10542, available from https://nrid.nii.ac.jp/ja/nrid/1000060464004/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: Yasuaki Oyama is an employee of Sompo-Japan Insurance Incorporated, which provided the claim files for the analysis in the present study. Yasuhiro Otaki serves independently as a medical and legal consultant for Sompo Japan Insurance Incorporated on an as-needed basis receiving appropriate fees. Other authors have declared that no competing interests exist. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
Introduction
The Medical Accident Investigation System was implemented by the Japan Medical Safety Research Organization (Medsafe Japan) in Japan in October 2015 [1]. This system targets unforeseen death caused by medical care that was reported as a medical accident, defined as “Death or stillbirth which are caused or suspected to have been caused by the care provided by employees of the medical institutions, and which are unforeseen by the administrator” [2]. This system aims to ensure medical safety by preventing the recurrence of similar medical accidents. In this system, each medical institution prepares and submits an In-Hospital Investigation Report to the Medical Accident Investigation and Support Center (ISC) of Medsafe Japan. The ISC then compiles and analyzes these reports to develop recommendations for preventing the recurrence of similar medical accidents. In March 2017, Medsafe Japan and the ISC released the recommendations with the “Analysis of deaths related to the complications of ‘Central Venous Catheterization’: First report” published as the first set of recommendations due to the repeated occurrence of unforeseen deaths associated with central venous catheterization (CVC)-related complications [3]. In this publication, 10 in-hospital investigation reports of the deaths were carefully analyzed in detail, and the results of the analysis were combined with the conventional findings. The recommendations include 9 items for preventing accidents, of which 6 were related to the indications for and practice of CVC, such as anatomic insertion site focusing on the internal jugular vein, puncture procedure using the ultrasound-guided method, and recommendations for avoiding fatal complications. In October 2017, 6 months after the publication, the CVC recommendations were used in manual reviews and training materials in many hospitals in a questionnaire-based survey, which was conducted by Medsafe Japan [4]. Although the recommendations are important to prevent the recurrence of similar CVC-related medical accidents, which specific recommendations to emphasize for prevention is unclear because the 10 deaths have not been compared with other CVC-related medical cases.
For physicians, a reduction in CVC complications is always a priority. Although CVC is an invasive medical procedure that is widely performed in children and adults, in numerous cases, incorrect indications or insertions using premature techniques can compromise patient safety with disastrous consequences. To properly perform CVC and achieve its original objectives, several clinical guidelines have been established [5–7], including the CVC guidelines of the Japan Society of Anesthesiologist [8]. Furthermore, to reduce the incidence of CVC complications, studies have focused on specific complications [9–11], including the study by Parienti et al. on the incidence of catheter infections and occlusions [12]. In addition, Ares et al. reported the indications, devices, and risks of CVCs in children [13], and Norris et al. [14] and Jaffray et al. [15] reported the complications of CVCs in children. Domino et al. analyzed the closed claims of CVC-related complications and identified various potentially fatal complications [16]. Closed claims held by insurers are currently used among different medical fields, including anesthesiology, to improve medical safety by preventing medical accidents [17–19]. We have also analyzed closed claims provided by Sompo-Japan (SJ), a leading insurer that covers >70% of all medical facilities in Japan, including various types of hospitals and clinics. These data report the characteristics of medical accidents in rheumatoid arthritis and suppurative arthritis to improve patient safety [20, 21].
Although closed claims are thought to represent only a portion of medical accidents and have a bias toward medical accidents that resulted in serious injuries, closed claims contain data on different types of medical accidents ranging from non-serious injuries to deaths as well as rare fatal medical accidents [22]. Therefore, these data may elucidate the recommendation points that should be emphasized to specifically prevent the recurrence of similar CVC-related deaths, including unforeseen death, by comparing CVC-related closed-claim cases (CCs) with CVC-related reported cases (RCs) documented as unforeseen deaths in the Medical Accident Investigation System. In this study, we aimed to compare and analyze CCs and RCs to identify points in the recommendations published by Medsafe Japan and ISC that should be emphasized specifically to prevent the recurrence of similar CVC-related deaths.
Materials and methods
Study design
This retrospective comparative study was conducted to review CVC-related closed malpractice claim cases treated at the Tokyo headquarters of SJ, defined as the closed-claim cases (CCs), and CVC-related death cases reported in the Medical Accident Investigation System, defined as the reported cases (RCs). This study complied with the Japanese epidemiologic study guidelines and was approved by the ethics committee of our university; Teikyo University Ethical Review Board for Medical and Health Research Involving Human Subjects (authorized number: Teirin19-059). To preserve anonymity in the present study, all claim files underwent a contextual de-identification process by SJ staffers before being provided to the reviewers. Therefore, the ethics committee waived the requirement for informed consent in this retrospective study.
Closed-claim cases from Sompo-Japan
The present study evaluated CCs related to CVC-related medical practices that were processed by professional staff at SJ over 15 years, between January 2002 and December 2016. The CCs analyzed in this study included data on various medical accidents, ranging from non-serious injuries to deaths. The coverage by SJ extends to >70% of all medical facilities in Japan, including various types of hospitals and clinics. This study was conducted at the Tokyo headquarters of SJ, which handles the highest number of claims within the company as a centralized library of claims for all of Japan. A claim was defined as a written statement demanding compensation for injuries caused by medical practice. [23] Claims were classified as closed if they were dropped, dismissed, or settled by monetary compensation after reconciliation or a judicial decision [24]. Claim files provided by the insurer contained various types of relevant information, including the initial reports from the insured party when the allegations arose; legal reports, such as judgment documents; expert opinions; and relevant medical records obtained from medical facilities [21]. A total of 8530 closed claims were processed at the Tokyo headquarters during the 15-year study period. Of these 8530 claims, 37 CVC-related claims (0.4%) were retrieved for this study. All the cases treated at the Tokyo headquarters of SJ during the period were included in the analysis, regardless of the judgment results. There was no overlap between CCs from SJ and the RCs from the Medical Accident Investigation System.
CVC-related death cases from the Medical Accident Investigation System
In October 2015, Medsafe Japan initiated the Medical Accident Investigation System to prevent the recurrence of similar medical accidents in Japan. In this system, unforeseen deaths caused by medical care were reported as medical accidents. In this system, medical accident is defined as “Death or stillbirth which are caused or suspected to have been caused by the care provided by employees of the medical institutions, and which are unforeseen by the administrator” [2]. If the case is judged to be a medical accident, the administrator explains the judgment to the bereaved family and reports it to the ISC. From October 2015 to December 2016, 226 cases were reported to the ISC as unforeseen death. Of these 226 cases, 10 (0.4%) were CVC-related death cases. Subsequently, in March 2017, Medsafe Japan and the ISC published “Analysis of deaths related to the complications of ‘Central Venous Catheterization’: First report” as the first set of recommendations for the prevention of recurrence of similar medical accidents. These recommendations include nine items to prevent CVC-related accidents (Table 1). In this study, we analyzed the characteristics of the reported death cases described in the recommendations.
Outcome measures
The background for CCs and RCs were compared. First, the descriptive statistical analysis considered the demographic data, such as disease for CVC, reason for CVC, and insertion site, for both CCs and RCs. The ratio of ultrasound guidance in CVC and the involvement of anesthesiologists in CCs were also analyzed. Second, the error type was analyzed for both CCs and RCs. The errors were divided into vascular access errors and use/maintenance errors, and the ratio of death cases in each error type was analyzed. Third, the anatomic insertion site and fatal complication types in the death cases were analyzed for both CCs and RCs. For the analyses of the anatomic insertion site and complication type, the insertion sites were classified as jugular, subclavian, and femoral, and the relationship between these sites and the fatal complication types was assessed. The judgments of each outcome were determined independently by the two co-authors of this study to control for potential bias from the reviewers’ personal interpretations.
Statistical analyses
Descriptive statistics were used to evaluate the data. Statistical significance, defined as a p value of <0.05, was determined using the Fisher exact test. Statistical analyses were conducted using R version 4.0.3 (R Core Team [2020], R: A language and environment for statistical computing, R Foundation for Statistical Computing, Vienna, Austria, http://www.R-project.org/).
Results
Background of the closed-claim cases and reported cases
In this study, we analyzed 37 CCs and 10 RCs. Summaries of RCs from the recommendations are presented in Table 2. The baseline data of CCs and RCs are presented in Table 3.
Of the 37 CCs, 12 were death cases (32.4%), whereas all 10 RCs were death cases. Of the 12 death cases in the CCs, cancer was the most common disease indicated for CVC in 6 cases (50%), and nutrition was the most common reason for insertion in 11 cases (91.6%). Of the 10 RCs, renal failure was the most common disease indicated for CVC in 3 cases (30.0%), and nutrition was the most common reason for insertion in 4 cases (40.0%). Comparison of CCs and RCs demonstrated no significant difference in the disease indicated for CVC (p = 0.26); however, a significant difference was observed in the reason for CVC (p = 0.03). Among the anatomic sites for CVC, the internal jugular vein was the most common insertion site in 5 CCs (41.7%) and 7 RCs (77.8%), with no significant differences between the CCs and RCs (p = 0.28). In the non-death CCs, the subclavian vein was the most common anatomic site, which was reported in 15 cases (65.2%). In the CCs, the catheter was inserted based on the landmark in all 37 cases, regardless of the anatomic site. In the RCs, the catheter was inserted under ultrasound guidance in 6 of the 10 cases, and the anatomic site was the internal jugular vein in all 6 cases. In the RCs in which the internal jugular vein was selected as the CVC site, catheterization was performed based on the landmark in only 1 case. In non-death CCs, 9 cases (50.0%) involved physicians with <5 years of experience after obtaining a physician license versus their involvement in 2 death CCs (28.6%). In addition, restriction of the physicians with <2 years of experience revealed 2 non-death CCs (11.1%) and 2 death CCs (28.6%). None of the CCs involved an anesthesiologist.
Vascular access and use/maintenance related to CVC according to error type
The error type of CVC-related accidents included vascular access in 35 cases (74.5%) and use/maintenance in 12 cases (25.5%) in CCs and RCs (Fig 1).
In CCs, no significant difference was observed between the proportion of deaths due to errors in obtaining vascular access and that due to use/maintenance (p = 1.00). CC, closed-claim case; RC, reported case.
Of the 35 cases related to vascular access, 18 were deaths (51.4%), including 9 CCs and 9 RCs. Of the 12 cases related to use/maintenance, 4 were deaths (33.3%), including 3 CCs and 1 RC. Among the CVC-related accident cases, most were related to vascular access than to use/maintenance, and the ratio of death cases was also higher.
Relationship between the anatomic insertion site and complication type in death cases
The anatomic insertion site and fatal complication types are presented in Table 4.
The internal jugular vein was the most common anatomic insertion site that resulted in fatal complications, with 5 (55.6%) of 9 cases in CCs and 7 (77.7%) of 9 cases in RCs. No differences were observed between the fatal complication types in CCs versus RCs. In the death cases related to internal jugular vein insertion, the complications of vascular injury occurred in 3 of 5 CCs (60.0%) and 3 of 7 RCs (42.9%). In the death cases due to internal jugular vein insertion, coagulopathy was observed in 3 of 5 CCs (60.0%) and 6 of 7 RCs (85.7%). In the vascular injury cases, coagulopathy was observed in all CC cases and 2 of 3 RCs (66.7%).
Discussion
This study aimed to compare and analyze CVC-related CCs and CVC-related RCs to identify points in the Medsafe Japan and ISC recommendations that should be emphasized specifically to prevent the recurrence of similar CVC-related death. In comparing the deaths of CCs and RCs, incidents in vascular access in jugular catheterization were observed as common characteristics. In the analysis of complication types, fatal bleeding complications caused by jugular catheterization were also observed as a common characteristic. In the death cases due to internal jugular vein puncture, coagulopathy was observed in 9 of the 12 death cases (75.0%). In the analyses of CCs, there were no death cases in which anesthesiologist performed CVC. When the practice of CVC to the internal jugular vein was compared between the death CCs and RCs, the ultrasound-guided method was used in 6 of 7 RCs (85.7%), whereas the landmark method was used in all 37 CCs.
Ultrasound guidance is safer than the landmark technique because physicians use ultrasound to guide the catheter placement [5, 25–27]. In recent years, the internal jugular vein has often been recommended as the first-line option in the selection of an anatomic site for catheter insertion. One of the reasons for this selection is that it is easier to access the jugular vein during CVC because the ultrasound-guided method enables direct observation. In addition, jugular catheterization can be performed to minimize the risk of pneumothorax compared with subclavian catheterization. It can also avoid infectious diseases more than femoral catheterization [6–8, 26]. Therefore, recommendations published by Medsafe Japan and ISC describe in detail the appropriate puncture technique under ultrasound guidance at the jugular vein, which can be expected to reduce CVC-related deaths by incorporating this into clinical practice. Some deaths in CCs may have been avoided using the ultrasound-guided method. However, bleeding complications in CVC cannot be completely avoided, even if catheterization is performed with appropriate use of the ultrasound-guided method. In the death cases due to internal jugular vein puncture, concomitant coagulopathy is conspicuous, and fatal complications due to bleeding may occur regardless of the use of ultrasound guidance. The risk of bleeding complications at CVC in patients with coagulopathy is well recognized among physicians. However, data indicate that vascular injury that occurs in patients with coagulopathy due to internal jugular vein puncture results in fatal complications. In unforeseen death cases, physicians may have been overconfident in ultrasound guidance and may not have seen the risk of bleeding seriously. Therefore, concomitant coagulopathy seems to be a critical risk of CVC-related death. CVC with appropriate ultrasound-guided method is important in avoiding CVC-related death but may be insufficient.
In Japan, anesthesiologists are mainly responsible for CVC in some specialized hospitals, whereas in many general hospitals, general physicians, including surgeons, are responsible for CVC [28]. Given that the guidelines for CVC have been published by anesthesiology societies in various countries, that anesthesiologists are highly experienced in performing CVC, and that none of the death CCs involved anesthesiologists in this study, anesthesiologists generally seem to have a deep knowledge of the safe performance of a CVC, including ensuring a safe puncture environment. Therefore, CCs and RCs may present a risk that is likely to be overlooked by non-anesthesiologists responsible for CVC. The results of this study suggest that physicians, especially non-anesthesiologists, may overlook the fatal bleeding risk, although they may have an abstract understanding that patients with coagulopathy have a risk of bleeding that can lead to death. Therefore, all physicians involved in CVC should accurately observe the risk of internal jugular insertion in patients with coagulopathy. The risks of CVC performed in the internal jugular vein in patients with coagulopathy should be reconsidered.
To establish the Medsafe Japan and ISC recommendations more effectively, this study emphasizes the following points. First, the indications for CVC in the internal jugular vein for patients with coagulopathy should be carefully reconsidered. In this context, item 1 of the recommendations that addresses the risk of a patient with coagulopathy should be greatly emphasized. Second, because vascular injury, hemopneumothorax, and hematoma can occur as unforeseen fatal complications, CVC in the internal jugular vein for patients with coagulopathy under ultrasound guidance should be performed in environments capable of addressing such complications. If this secure environment cannot be established, then CVC in the internal jugular vein for patients with coagulopathy should be temporarily postponed.
This study has several limitations. First, the recommendations were first published soon after the initiation of the Medical Accident Investigation System. This system is continuously evolving and accumulating more cases, and many more cases are currently available. Therefore, new findings may be obtained in the reanalysis of CVC-related RCs. Second, this study was a retrospective review of CCs provided by one department of SJ and did not represent all CVC-related medical claims. Therefore, the results may only be applicable to a single aspect of malpractice claims. Despite these limitations, this study was the first to evaluate the Medsafe Japan and ISC recommendations based on unforeseen deaths related to CVC in the Medical Accident Investigation System in Japan. The clinical management of diseases is expected to increase based on specialization and complexity, and it will be necessary to ensure patient safety in the future. We hope that the findings of the present study will help physicians responsible for CVC to better understand the need for preventing CVC-related fatal complications.
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