In this study, different time intervals from initial hemorrhage to admission and followed by endovascular treatment were reported. Prompt treatment (the same day of admission) after admission to our hospital was observed in over 90% aSAH patients. Unfortunately, the major delay to endovascular treatment was pre-hospital delay including delayed admission and delayed transfer rather than in-hospital delay. Multivariate analysis showed that younger age and good Fisher score were independent risk factors for admission delay.
Over 90% patients were treated at the day of admission, namely, the interval between admission to endovascular treated was less than 24 h in most patients. The interval between admission to endovascular treatment was considerably shorter in our hospital than any other previous studies . Sarmiento et al. reported the time intervals between admission and treatment of 38,827 aSAH patients, with 9.3% patients not treated within 2 days after admission . Potential explanations for treatment delay in aSAH patients are the lack of aneurysm team available for 24/7, lack of management experience due to low volume of aneurysm cases, lack of routine provision of clipping or coiling at weekends and nighttime, etc. In our hospital, four cerebrovascular teams (with over 90% of cerebrovascular disease and 40~60% of intracranial aneurysms) were established, with at least one team on duty for 24/7. The annual number of patients with intracranial aneurysms admitted to our hospital was also increased, with annual over 700 aneurysms since 2016. With nine interventionalists that could handle intracranial aneurysms, we have the ability to treat the intracranial aneurysms 24/7 and initialize endovascular treatment as soon as possible, even in nighttime. In addition, CT, DSA and CTA were all available for 24/7, making it possible to provide full-time and prompt treatment for aSAH patients.
The clinical outcome of the patients in this study was comparable in comparison to large aSAH studies [14, 15]. An explanation for this might be ultra-early treatment for admitted patients. The following policy was applied to treat aSAH patients as soon as possible: (1) the concept of “time is brain” was extrapolated to patients with aSAH. The 24/7 h policy of thrombolysis and thrombectomy for patients with acute ischemic stroke was also extrapolated to aSAH patients. (2) Physicians and interventionalists were prepared when the patients were still in transport. (3) Patients with aSAH were immediately delivered to the operation room to receive endovascular treatment after admission. In addition, the application of pre-hospital and in-hospital logistics for ultra-early treatment of acute ischemic stroke would significantly reduce the delay of admission and treatment [16,17,18]. CT-unit in the ambulance has been used for patients with acute ischemic stroke in China, which shortens the time to diagnosis and treatment . It might also be used for patients with aSAH.
The treatment of intracranial aneurysms is more concentrated in high-volume hospitals in China. The impact of case volume of hospitals on the management of aSAH patients have been reported in previous studies [20, 21]. High-volume hospitals were related with lower mortality rate and better clinical outcome. Thereafter, aSAH patients were recommended to be transferred to high-volume hospitals if possible. Low-volume hospitals were also recommended to establish cerebrovascular team, with cerebrovascular surgeons and endovascular specialists that could provide multidisciplinary and systematic neuro-intensive care. Since quantitative patients were admitted, a high-volume hospital could provide 24/7 prompt and experienced treatment for aSAH patients. Our experience indicated that cerebrovascular team could significantly improve the medical service for aSAH patients, including ultra-early treatment and better clinical outcome.
Although the intervals between admission to endovascular treatment were short, there is still room for improvement to optimize ultra-early aneurysm treatment. Pre-hospital logistics could be optimized by immediate and direct transfer from primary hospitals to treatment centers or high-volume hospitals. Similar with acute ischemic stroke, “time is brain” principle should be obeyed when transferring aSAH patients.
Restrictions should be highlighted of this study. Firstly, all data were retrieved from medical record system in our hospital. Thus, treatment delay caused by transfer to primary medical centers would be impended. Secondly, this study was a retrospective single-center study and thus could not provide extrapolation of currently overall treatment status of aSAH, since time intervals were different among countries, regions, and even hospitals [22, 23]. Thirdly, the influence of admission delay time discussed in our paper was more focused on patient themselves; the factors of hospital and doctors were less discussed, which may need more attentions in further studies. Lastly, the time points were retrieved from the medical records system of our hospital and precise time could not be retrieved in all patients. Thus, the measurement unit of time intervals would be day rather than hours or minutes, which we considered proper and rational in our hospital. Lastly, emergency treatment policy for aSAH was quite different among hospitals. In our hospital, aSAH was considered to be disastrous which needed to be treated immediately if possible. However, this policy is rarely seen in most hospitals in China and rarely reported in previous studies. Further multi-center survey was warranted to investigate the treatment status of aSAH.