With a simple and easily-implementable quality improvement initiative, we have increase IVT rate from 14.4% to 20% and reduced median DNT by 23 minutes to 40 minutes. Our results are better than recently reported benchmarks of 14.3% IVT rate and 52 minute DNT at the 134 CSCs in the U.S.14
Despite significant improvement, our results are still suboptimal compared with the benchmarks from centralized Hospital Systems in other developed countries.4-9 For example, the hospital district of Helsinki and Uusimaa has a population of 1.6 million and a centralized regional emergency medical service (EMS).4,15 All patients deemed as candidates for stroke therapies are transported with high priority and pre-notification to the Helsinki University Hospital, which is the only 24/7 neurology service to provide care for AIS. As a high volume and centralized Stroke center, the Helsinki University Hospital was very efficient due to thorough training for all EMS and ED staff, and long-standing experience.4,15
In contrast, our CSC, the only academic medical center in Orange County, California, is one of the 9 stroke receiving centers serving a population of 3.19 million.16 In such decentralized healthcare system, it is very challenging for all of the 9 stroke receiving centers to implement comprehensive protocols to achieve the fastest DNT for IVT.4-11,14
Our quality improvement initiative is easily-implementable, effective and safe. Uncontrolled hypertension is one of the most frequently reported factors causing delayed DNT.5,8,17 In a single center study, uncontrolled hypertension was associated with more than 30 mins delay in DNT.16 Per AHA/ASA guidelines, IVT should be held until BP is less than 185/110 mmHg.1 In the pre-intervention group, severe hypertension was managed by the ER physicians. During post-intervention period, stroke team was managing hypertension in the CT suite and ED without any delay as soon as patient was deemed to be eligible for IVT. This simple change effectively minimized hypertension-related delay for IVT.
Waiting for blood testing results is another common reason for delay up to 60 minutes in some eligible patients.5,18 Previous studies reported extremely low rates of unidentified coagulopathies and thrombocytopenia that would have been a contraindication for IVT.18-20 Therefore, we implemented the initiative for IVT administration without waiting for blood test results unless patients were taking anticoagulants or had history of severe thrombocytopenia. There was no significant difference in the rate of sICH between pre-intervention and post-intervention groups. No patient suffered sICH from IVT due to undiagnosed coagulopathy. In addition, the rates of sICH in our cohort were much lower than reported in clinical trials,2 confirming the safety of our simple initiative.
Another change we made in practice in January 2015 was to give IVT in the CT suite. As CT imaging is an indispensable diagnostic tool for decision-making for IVT, shortening the CT imaging-to-needle time may significantly improve DNT.4,5,21,22 Our data confirmed that giving IVT in the CT suite minimizes the delay from CT to needle time without significant risk of complications.
Of note, the initial NIHSS scores in the post-intervention group was significantly lower than that in the pre-intervention group. There were numerous possibilities to explain why more patients with non-disabling stroke (NIHSS £ 4) during the post-intervention group. Previous studies showed longer DNT in patients with minor stroke, possibly due to higher chance of atypical symptoms, delayed neurology notification and diagnosis.23,24 The early diagnosis and decision making from better implementation of the Stroke: Target strategies in the post-intervention group would naturally increase IVT for patients with minor strokes. In addition, better stroke aware, risk management and stroke prevention in recent years may have also decreased the ratio of patients with more severe stroke.
The strength of our study is the use of 3 easily-implementable changes to reduce DNT without additional infrastructure cost or undue burden on the stroke team and ED staff. This simple initiative is effective, safe and easily replicable at other CSCs and PSCs in the U.S. and other countries.
This study has some limitations. First, it is a single center study. We used pre-intervention period as historic control. Our post-intervention data could be affected by unmeasurable confounding factors and gradual improvement in stroke care due to better training and experience. Second, although we had a one-year transition period for full implementation of the 3 changes, there might be incomplete adherence during the post-intervention period. Since incomplete adherence to the changes would likely lead to prolonged DNT, it is possible that the simple changes could work better if the initiative was applied all the time effectively. Third, we have not addressed other hurdles in delaying DNT, such as point of care coagulation testing for patients taking anticoagulants, moving directly from the EMS stretcher to CT scanner.4,7,15 Additional easily-implementable changes at decentralized healthcare system may significantly reduce DNT at CSCs and PSCs in the U.S..