The present study assessed the current status and management of OPAT at a single hospital in the Republic of Korea, for the first time. In Korea, post-acute care patients refer to long term care facility to maintain parenteral antibiotics. But there are no fees or reimbursement for OPAT management and few institutions implement OPAT management team. This study may show the current status of OPAT in Korea. During the 6-month study period, significant number (577 episodes) of OPAT prescriptions were made through outpatient or referral models, and we investigated the administration model, follow-up outpatient visit rates after prescription, and monitoring test rates.
We found that prescriptions from the top 5 departments that prescribe OPAT often accounted for approximately 70% of all prescriptions. This suggests that pre- and post-prescription management can be introduced preferentially to departments with high rates of prescription. Ertapenem, ceftriaxone, and kanamycin were often prescribed at our hospital, but studies of OPAT at other hospitals reported that ceftriaxone and teicoplanin were frequently prescribed.(12–14) The use of teicoplanin was low at our hospital as we use vancomycin as first line treatment for antibiotic-resistant gram-positive bacterial infection, such as methicillin-resistant Staphylococcus aureus. This difference is thought to be caused by each hospitals' had different patient groups and antibiotic prescribing behaviors. Thus, it is important that each hospital should develop its own strategy for antimicrobial stewardship based on the analysis of antibiotic use of the institution.
Common indications for parenteral antibiotics in this study included urinary tract infection, respiratory infection, intra-abdominal infection, and bone and joint infection, consistent with other OPAT studies reporting that bone and joint infections are major indications for OPAT.(13–17) This finding might be due to the clinical characteristics of bone and joint infections requiring relatively long uses of parenteral antibiotics. In contrast, other studies have also reported that skin and soft tissue infections are major indications for OPAT.(12, 14, 16, 17)
In the referral model, 46.6 % of episodes had clear documentation of the facility selected to administer the antibiotics, and this indirectly suggests that management of administration of OPAT is inadequate. In the referral model in which the administration of OPAT is handed over to another facility, the transition can be made through hospitalization or outpatient visits to general hospitals, nursing hospital, clinics, and other various types of facilities. In Korea, there is no fee claims available for these referrals, and sharing of treatment information is also not systematic. As different facilities may be capable of different levels of tests and monitoring, it is important to confirm the facility to which the patient is being referred in advance to confirm whether the facility is capable of maintaining and managing OPAT. Moreover, systematic changes should be made to support continued treatment and management through exchange of information between facilities.
More patients in the outpatient model had follow-up outpatient visits after the administration of OPAT than those in the referral model. This may be because patients who continued their care at another facility may have been followed up at that facility, thus not presenting to our hospital for follow-up. In addition, patients who received acute treatment at our hospital may have continued their treatment at a medical facility close to their home. In terms of the implementation of tests necessary for monitoring of parenteral antibiotics, the rate was higher in the outpatient model than in the referral model with a non-significant difference between the two models. Based on these findings, when follow-up at the same hospital is not carried out, the list of necessary tests for management of parenteral antibiotics and possible side effects should be offered at the time of referral. Subsequently, continued management should be offered through phone calls with patients.
For management of OPAT, not only OPAT team but antimicrobial stewardship intervention can be helpful. When we evaluated the possibility of changes in the route of administration prior to antibiotics administration, conversion to oral antibiotics was considered to have been possible in 3.7% of prescriptions. Our hospital manages restricted antibiotics by regular ID consultations, and there is an electronic alert with automated consultations for positive blood culture test, so it seems to be well managed(18). And Pharmacists in the antimicrobial stewardship team continue to offer the intervention (parenteral-to-oral conversion) to inpatients at our hospital.(19, 20) And antimicrobial stewardship team can suggest appropriate duration of antimicrobial therapy. In the future, prescription of parenteral antibiotics for patients planned for discharge should be reviewed in advance to reduce inappropriate antibiotic use.
In the present study, adverse drug reactions were confirmed in 3.6% of prescriptions of parenteral antibiotics in outpatient and referral models, and less than 1% of prescriptions led to emergency room visits or hospitalizations associated with adverse drug reactions. However, a previous study reported that adverse reactions were seen in 18% of cases within 2 weeks of discharge,(12) and another study reported that re-hospitalization was seen in up to 27% of patients.(21) Referring to the other studies, since only medical records were analyzed retrospectively, mild side effects might not be recorded by physicians and it cannot be recognized in our study. Moreover, although we did not confirm any catheter-associated bloodstream infections in this study, these infections were frequently reported in studies conducted in other countries.(13, 22) In Korea, self-administration of intravenous agents by patients is not allowed, and patients are often discharged without central venous catheters. These differences in practice may have led to the differences seen in the results.
A few limitations should be considered when interpreting the results of this study. First, because of retrospective nature of this study, we could not assess the treatment outcome, adverse reaction of antibiotics, whether antibiotics had changed or added etc. in patients without follow-up visit. Second, when no follow-up visits were done, more adverse reactions than those documented could have happened. However, as these were not documented, the number of adverse reactions could have been underestimated given the retrospective design of the present study. Last, since this study was conducted at a single hospital, the results may be different from other hospitals in South Korea.
This study investigated the departments that frequently prescribe parenteral antibiotics for outpatients and referred patients, as well as frequently prescribed antibiotics and the indications for them. The study also found that appropriate candidates for monitoring should be selected prior to administration of parenteral antibiotics and that monitoring should be implemented. This study is significant in that it was able to confirm the participants who require monitoring of parenteral antibiotics, the scope of monitoring, and the necessity of a monitoring system through its findings.