2025 年 19 巻 1 号 論文ID: oa.2024-0082
Objective: As a solution to the shortage of and overwork among physicians, task shifting and task sharing have been proposed for health-care professionals. This study aimed to investigate the role of nurse practitioners (NPs) in neurovascular interventions and evaluate the validity of task shifting in our institute.
Methods: Medical records from 684 neurovascular intervention cases from 2020 to 2023 were retrospectively reviewed, and the tasks performed by NPs were investigated. Additionally, the procedure times between cases in which NPs acted as the first assistant alongside a physician (NP + physician group) and those in which 2 physicians performed the procedure (physician + physician group) were compared.
Results: The main tasks performed by NPs included preoperative checks, assistance during the procedure, postoperative care, the initial handling of complications, and inputting orders. No significant differences in procedure times were found between the NP + physician and physician + physician groups.
Conclusion: NPs showed potential for task shifting in perioperative neurovascular interventions, particularly in assisting, providing care, inputting orders, and initially handling complications. However, further discussions and improvements are needed regarding task shifting in emergency cases and work arrangements for NPs.
As part of the ongoing reform of work practices among physicians, task shifting from physicians to nurses has been proposed. In June 2014, following an amendment to the Public Health Nurses, Midwives, and Nurses Act, the “Nurse Training System for Specified Medical Interventions” was established. This system enabled nurses who had undergone training at designated institutions to perform specific acts following procedural guidelines. Here, 38 procedures are defined as specific acts by an ordinance of the Ministry of Health, Labour and Welfare of Japan.1) Nurses who complete this training are referred to as “nurses trained in specific acts.” The curriculum varies from e-learning to graduate school education, and the number of specific acts that can be acquired differs. Individuals who undergo training for specific acts in graduate school and pass the nurse practitioner (NP) qualification examination administered by the Japan NP Education Graduate School Council are called NPs. While nurses trained in specific acts are authorized to practice the specific acts they have acquired, NPs are also permitted to perform medical acts other than specific acts under the direct supervision of physicians.2) The scope of medical acts is left to the discretion of the facility or medical department. As of March 2023, there were 6875 nurses trained in specific acts nationwide, among whom there were 759 NPs as of April 2023. In our neurosurgery department, there are 2 assigned NPs, and their scope of practice extends across outpatient clinics, wards, operating rooms, interventional radiology rooms, and intensive care units, involving patient care in all areas. While task shifting by NPs has been extensively reported in surgical departments, including emergency and neurosurgery units, to our knowledge, few studies have examined their involvement in neurovascular interventions.3–8) Given this background, the present study aimed to investigate the duties of NPs in neurovascular interventions in our neurosurgery department and evaluate the validity of task shifting.
Among 684 cases of neurovascular interventions at Fujita Health University Bantane Hospital performed as scheduled surgeries from March 1, 2020, to December 31, 2023, this study targeted cases of coil embolization (Coil), carotid artery stenting (CAS), percutaneous transluminal angioplasty (PTA), and flow diverter treatment (FD). Emergency cases were excluded. The medical records of the targeted cases were retrospectively reviewed to extract the tasks performed and the number of postoperative abnormal events handled by NPs. Postoperative abnormal events were defined as conditions requiring patient examination that were brought to the attention of the physician or NP through a telephone consultation with a ward nurse. Data were extracted for the period during which the NPs were assigned, from April 1, 2021, to December 31, 2023. Additionally, the procedure times between cases in which NPs acted as the first assistant alongside a physician (NP + physician group) and those in which 2 physicians performed the procedure (physician + physician group) were compared. This comparison of procedure times was conducted for cases performed between April 1, 2020, and December 31, 2023. Procedure time was defined as “the time from puncture to hemostasis initiation.” The Mann–Whitney U-test was used to compare procedure times between the 2 groups after confirming the normality of the data. The Kruskal–Wallis test was used to compare procedure times among different procedures after confirming the normality of the data, followed by post hoc tests using the Bonferroni method. All statistical analyses were conducted using SPSS version 29.0 (IBM Japan, Tokyo, Japan), with the significance level set at 5%. This study was approved by our local ethics review board (NM23-352).
Of the 2 NPs, 1 had worked as an operating room nurse for 9 years prior to becoming an NP and was assigned to the neurosurgery department in her third year as an NP. During the study period, she was in her fourth to sixth year as an NP. Since being assigned to the department, she has primarily worked in the operating room. The other NP worked on various wards and in intensive care units for 10 years before becoming an NP and was assigned to the neurosurgery department in her third year as an NP. During the study period, she was also in her fourth to sixth year as an NP. Since being assigned to the department, she has mainly worked in the interventional radiology room.
During the study period, there were 684 neurovascular intervention cases (231 Coil, 211 CAS, 106 PTA, 67 FD, 35 other, and 34 emergency). To examine the work content of endovascular treatment alone, emergency cases that may have required additional treatment, such as craniotomy, were excluded. The number of cases analyzed was 615. Since April 2021, when the NPs were assigned, there have been 594 eligible cases; statistics on the NPs’ duties were provided for these 594 cases.
The main tasks performed by NPs included preoperative checks, assisting during the procedure, handling postoperative abnormal events, postoperative care, and inputting orders. NPs conducted preoperative checks in 433 cases (72.9%), while the remaining 27.1% were performed by the attending physician. The preoperative checks included reviewing medical history, assessing antiplatelet medication status, confirming preoperative test results, checking for allergies and contraindications to contrast agents, and inputting premedication as necessary. Although the NPs conducted the preoperative checks, no treatment delays due to inadequate preoperative preparation were found.
Among the cases involving postoperative abnormal events, NPs responded to 36 cases and physicians to 47 cases. First calls to NPs were made for issues such as puncture site bleeding, changes in vital signs, and the onset of paralysis (Fig. 1). The decision on whether to call the physician or NP first was left to the discretion of the nursing staff. NPs responded to 26 cases during working hours and 10 outside working hours, while physicians responded to 17 cases during working hours and 30 cases outside working hours (Fig. 2).
Postoperative care provided by NPs primarily included 323 cases involving a compression bandage, followed by 41 cases of suture removal and 14 cases of arterial line insertion. Suture removal and arterial line insertion were performed as needed based on the patient’s condition and were not mandatory for all cases.
The inputting of orders primarily consisted of imaging studies and injection orders (Fig. 3).
There were 396 cases (66.6%) in which NPs assisted during the procedure. NPs were responsible for tasks such as preparing the sterile field, preparing the infusion giving set, preparing the contrast injector, operating the angiography equipment at each stage, setting up the roadmap, preparing and connecting the guiding catheter to the infusion giving set, preparing the balloon catheter, preparing and connecting the microcatheter to the infusion giving set, and preparing and connecting the microguidewire to the reflux circuit. Among the cases where NPs assisted, 264 (44.4%) involved NPs acting as the first assistant alongside a physician in a 2-person team (NP + physician group). A comparison of procedure times between the NP + physician and physician + physician groups for all cases is shown in Table 1. No significant differences were observed between the NP + physician and physician + physician groups. However, the doctor’s total treatment time was significantly shorter in the NP + physician group compared to the physician + physician group (190.64 ± 101.62 vs. 72.70 ± 38.04 min, p <0.001).
| Physician + physician (n = 190) |
NP + physician (n = 264) |
p value | |||||
|---|---|---|---|---|---|---|---|
| Mean | SD | Median | Mean | SD | Median | ||
| Treatment time (min) | 69.55 | 45.63 | 63.00 | 72.70 | 38.04 | 66.00 | 0.091 |
| Physician + physician (n = 190) |
NP + physician (n = 264) |
p value | |||||
|---|---|---|---|---|---|---|---|
| Mean | SD | Median | Mean | SD | Median | ||
| Treatment time (min) | 190.64 | 101.62 | 175.00 | 72.70 | 38.04 | 66.00 | <0.001 |
Statistical intergroup comparisons were made using the Mann–Whitney U-test. Cases with blanks in the medical record were excluded.
n, number of procedures; NP, nurse practitioner; NP + physician group, NPs acted as the first assistant alongside a physician; physician + physician group, 2 physicians performed the procedure; SD, standard deviation
During the procedures, complications occurred in 8 cases (2 cases of ruptured cerebral aneurysms, 1 case requiring vascular surgery consultation due to puncture site bleeding, 1 case of seizure, 2 cases of device trouble, 1 case of deteriorating respiratory condition, and 1 case of decreased cerebral blood flow). Of these, 4 cases (1 case requiring vascular surgery consultation due to puncture site bleeding, 1 case of device trouble, 1 case of deteriorating respiratory condition, and 1 case of decreased cerebral blood flow) occurred in the NP + physician group. The remaining 4 (2 cerebral aneurysm ruptures, 1 attack, and 1 device problem) occurred in the physician + physician group. When complications occurred, NPs temporarily suspended their assistance role and performed tasks such as medication administration, monitoring, assisting in airway management, and inputting orders for additional tests such as blood sampling.
In this study, we investigated the duties of NPs during the perioperative period of neurovascular interventions and compared the procedure times between cases where NPs acted as the first assistant and cases performed by 2 physicians. NPs at our hospital consistently intervened from preoperative preparation to postoperative care. Studies investigating task shifting by NPs in Japan have shown that NPs primarily assist with order inputting and procedures, resulting in a reduction in physicians’ workloads.4–7) Similar results have been reported in studies targeting surgical departments (e.g., cardiovascular surgery, gastrointestinal surgery, and neurosurgery), indicating that NP assistance with order inputting and procedures is a significant aspect of task shifting in surgical departments.8) In our study focused on neurovascular interventions conducted in the neurosurgery department at our hospital, we also observed frequent instances of NPs performing tasks such as releasing pressure and inputting orders, consistent with previous research findings. One characteristic of neurovascular interventions at our hospital is that a preoperative check is conducted in all cases. Because all neurovascular interventions at our hospital during the research period were performed under local anesthesia, there were no preoperative outpatient visits to the anesthesia department. Therefore, personnel were required to conduct the preoperative checks. No issues were found regarding preoperative checks during the intraoperative and postoperative periods, suggesting that task shifting in neurovascular interventions in the neurosurgery department may be considered feasible in the future. NPs assigned to medical departments have the advantage of easy information sharing with physicians. In this study, no issues with information sharing for preoperative checks were observed.
No significant difference in procedure times was found between the NP + physician and physician + physician groups for all cases. The fact that the presence of an NP as the first assistant did not affect procedure time suggests the potential for task shifting. Doctor’s total treatment time was significantly shorter in the NP + physician group compared to the physician + physician group. This difference indicates that task shifting reduced physician work hours.
The incidence of complications during the procedure also did not differ significantly. However, additional studies on perioperative complications are required to assess the safety of task shifting by NPs.
During any procedural complication, NPs responded according to the situation, including assisting with tasks outside the immediate procedure and inputting orders for additional tests. Typically, neurovascular interventions at our hospital are performed by 1 operating physician, 1 surgical scrub assistant, 1 circulating nurse, and 1 radiology technologist. The complications encountered in this report often prioritized stabilizing the patient’s overall condition over catheter manipulation, leading NPs to collaborate frequently with circulating nurses. In cases involving a deteriorating respiratory condition, requests for assistance from other physicians were made. In emergency situations where multiple tasks need to be addressed simultaneously, having only 1 physician may pose a risk of delayed response. The ability of NPs to function effectively as the first assistant was likely significantly influenced by having a senior surgeon as the operating physician. It was perceived that working with less experienced physicians or those less skilled in troubleshooting might pose higher safety risks compared to working with a senior surgeon.
The response to postoperative abnormal events was handled by NPs in 43.3% of cases. The items addressed were similar between physicians and NPs. NPs provided initial responses but reported to physicians and sought instructions for subsequent tests or treatments. Additionally, in situations deemed urgent by NPs, physicians joined them to address the complications. This setup prevented any issues caused by NPs acting independently. The advantage of NPs providing initial responses lies in not interrupting physicians’ ongoing consultations or tasks. While timely responses from physicians during outpatient, surgical, or interventional radiology hours may be challenging, the initial actions of the NPs likely contributed to reducing the workloads of the physicians. However, looking at response times, NPs predominantly responded during clinic hours, while physicians responded more frequently after hours. This is due to the daytime-only work schedule for NPs at our facility. Harsh working conditions for physicians include being on call or on standby. Moreover, compared with other specialties, neurosurgery has been shown to have the highest amount of overtime and holiday work hours.9) While efforts are made to regulate consecutive shifts after being on call, regular shifts following on-call duty remain unregulated. In a study involving 35 cardiac surgeons, more than half of the respondents reported a decrease in performance to less than 80% of normal levels after being on call.10) Given that decreased physician performance significantly affects patient safety, there is a need to implement task shifting outside regular working hours in the future.
The working style and affiliations of NPs vary depending on the facility. NPs affiliated with clinical departments, like ours, typically spend more time with physicians, allowing them to intervene in patient care while understanding treatment plans. On the other hand, NPs affiliated with nursing departments are confined to their assigned wards and have a limited scope of action but spend more time with patients, nurses, and other health-care professionals, enabling them to notice changes quickly. While the results of this study suggest that NPs contribute to task shifting for physicians, there are reports indicating that NPs affiliated with clinical departments have significantly longer working hours compared with those affiliated with nursing departments.11) The 10 instances where NPs responded outside clinic hours to postoperative complications were typically when they were on site before their starting time, working overtime for other reasons, or when brain vascular interventions extended beyond clinic hours and they were still on duty. Additionally, near the end of the workday, ward nurses may assume that NPs are still on site, leading to phone calls for assistance. Such circumstances indicate the existence of after-hour responses. Control over overtime work is essential not only for physicians but also for NPs; considerations such as increasing staff or implementing shift systems are necessary. Another problem is that when NPs assist patients during procedures, they are unable to respond in a timely manner to issues that arise on the ward. In the future, facilities that introduce NPs will need to employ them in a manner that allows them to realize the working style desired by both physicians and nurses.
From the above, it is evident that NPs contribute to task shifting for physicians by conducting physical assessments, performing necessary procedures based on specific acts, and entering orders on behalf of physicians. However, it is important to recognize that NPs are not physicians. Rather than behaving like physicians, it is crucial for NPs to understand their own limitations and adopt an attitude of collaboration with their surroundings while advancing patient care. On the other hand, physicians need to assess the capabilities of NPs and adopt a supportive attitude. Therefore, it is essential for NPs and physicians to establish appropriate communication and build trust. With such collaboration in place, the entire health-care system could be expected to function more efficiently.
The present findings suggest that in the perioperative period of neurovascular interventions, NPs are capable of task shifting as assistants, performing procedures, entering orders, and managing complications. It is crucial for NPs to understand their limitations and seek support from their colleagues when necessary, as this attitude is essential for maintaining safety. Further consideration of task shifting in emergency cases and the working conditions of NPs is needed.
The authors declare that they have no conflicts of interest.
