Abstract
Background
Recent studies have shed light on the continued prescription of inpatient medications upon hospital discharge, despite the original intent of short-term inpatient therapy. Amiodarone, an antiarrhythmic associated with significant adverse effects with long-term use, is commonly used for new-onset atrial fibrillation in critical illness (NAFCI). Although it is often preferred in this setting of hemodynamic instability, a prescription for long-term use should be carefully considered, preferably by a cardiologist. This study was conducted to evaluate the incidence of patients discharged on amiodarone without a cardiology consult or referral after being initiated on amiodarone for NAFCI.
Methods
We conducted a retrospective review of all patients newly prescribed amiodarone for NAFCI over a 2-year period. The primary outcome was the percentage of patients who were continued on amiodarone upon hospital discharge without review by or outpatient referral to a cardiologist.
Results
Of the 100 patients who met inclusion criteria, 59 patients were prescribed amiodarone upon hospital discharge. Of these, 48 patients (81.4%) had converted to normal sinus rhythm with the resolution of critical illness. Of 100 patients, 23 received prescriptions for amiodarone upon discharge without a cardiology consult or referral.
Conclusion
Amiodarone was frequently continued upon discharge without referral to a cardiologist in patients initiated on this therapy for NAFCI. This may contribute to unnecessary long-term therapy, thereby increasing the risk for significant side effects, drug interactions, and increased healthcare costs. This study suggests that careful medication reconciliation through all transitions of care, including discharge, is essential.
Keywords
Clinical Significance
- •Amiodarone was frequently continued upon discharge without referral to a cardiologist for patients with new-onset atrial fibrillation of critical illness (81.4%), despite conversion to normal sinus rhythm.
- •Unnecessary prescriptions of amiodarone may contribute to increased risk of side effects, drug interactions, and healthcare costs.
- •Careful medication reconciliation through all transitions of care, including discharge, is essential.
Atrial fibrillation (AF) is a common cardiac arrhythmia in the United States, frequently seen in the setting of critical illness due to severe physiologic stress. This new-onset atrial fibrillation in critical illness (NAFCI) in patients with no prior history of AF can be triggered by hypo- or hypervolemia, hypoxemia, sympathomimetic medications, adrenergic states such as traumatic injury, and pain or systemic inflammation as seen in septic shock.
1
The incidence of NAFCI ranges from 5% to 46% of patients admitted to the intensive care unit (ICU).2
, 3
Importantly, NAFCI may be associated with increased length of ICU stay and mortality.3
Amiodarone is frequently prescribed for rate and rhythm control for these patients, owing to its favorable safety profile in patients who have hemodynamic instability and for those with compromised left ventricular function.4
However, the long-term use of amiodarone must be closely monitored because this therapy can cause serious adverse effects, including toxicities affecting the lungs, liver, eyes, and thyroid.5
As the severity of critical illness improves, patients commonly convert back into normal sinus rhythm, and long-term amiodarone therapy is likely not necessary. However, with the transition of care to new prescribers not directly involved in the initial decision to start amiodarone, it is possible that patients initiated on this therapy in the ICU may unnecessarily be continued upon discharge. By identifying the magnitude of this issue, appropriate strategies to deprescribe amiodarone appropriately can be implemented.
The objective of this study was to evaluate the incidence of patients prescribed amiodarone for NAFCI who were discharged on long-term therapy without an assessment by or referral to a cardiologist.
Methods
This study was conducted at a tertiary care center in Tucson, Arizona and approved by an institutional review board. A retrospective review of electronic medical records was performed of adult patients with NAFCI initiated on intravenous amiodarone followed by oral amiodarone who were admitted to the Surgical Trauma ICU, Medical ICU, and Cardiac ICU between November 1, 2013 and September 17, 2015. Patients were excluded if they had been prescribed amiodarone before admission, had a history of AF, received only intravenous or oral amiodarone, underwent coronary artery bypass graft, or died during the hospital admission.
The primary outcome was the incidence of patients initiated on amiodarone in the ICU who were prescribed an unlimited prescription upon discharge without documentation of an evaluation by or outpatient referral to a cardiologist.
Patient demographics were recorded on the day of hospital admission. Patients' hospitalization data included admitting ICU diagnosis, length of stay, disposition location, and duration of amiodarone use during hospitalization.
Results
A total of 277 patients were evaluated. Among these patients, 177 did not meet inclusion criteria, leaving 100 patients eligible for statistical analysis. Patient demographic data and length of hospital stay are listed in Table. Of those 100 patients, 59 were continued on amiodarone upon hospital discharge. Forty-eight patients discharged on amiodarone (81.4%) had converted to normal sinus rhythm with resolution of the critical illness. Twenty-three of 100 patients were prescribed amiodarone without an assessment by or referral to a cardiologist.
TablePatient Demographics and Amiodarone Use
| Characteristics | Amiodarone Prescribed Upon Discharge (n = 59) | Amiodarone Discontinued Before Discharge (n = 41) | P Value |
|---|---|---|---|
| Age (y) | 68.0 ± 13.5 | 69.0 ± 18.0 | .883 |
| Male sex | 36 (61) | 30 (73.2) | .283 |
| Race/ethnicity: white/non-Hispanic | 41 (69.5) | 29 (70.7) | .763 |
| Comorbidities | |||
| Hypertension | 38 (64.4) | 25 (61.0) | .834 |
| Stroke/TIA | 4 (6.8) | 4 (9.8) | .713 |
| Thromboembolism | 6 (10.2) | 5 (12.2) | .756 |
| Vascular disease | 11 (18.6) | 7 (17.1) | 1.000 |
| Diabetes mellitus | 10 (16.9) | 10 (24.4) | .448 |
| Congestive heart failure | 7 (11.9) | 7 (17.1) | .561 |
| Hypothyroidism | 13 (22.0) | 4 (9.8) | .175 |
| Length of hospitalization (d) | 17.0 ± 20.5 | 22.0 ± 16.0 | .071 |
| Length of ICU stay (d) | 8.0 ± 9.0 | 11.0 ± 15.0 | .034 |
| Primary diagnosis when admitted to ICU | .984 | ||
| Respiratory failure/AMS | 16 (27.1) | 11 (26.8) | |
| Sepsis | 7 (11.9) | 5 (12.2) | |
| Postoperative noncardiac surgery | 12 (20.3) | 11 (26.8) | |
| Postoperative cardiac surgery | 9 (15.3) | 5 (12.2) | |
| Cardiac-related conditions | 13 (22.0) | 8 (19.5) | |
| Others | 2 (3.4) | 1 (2.4) | |
| ICU units | 1.000 | ||
| Cardiac ICU | 26 (44.1) | 18 (43.9) | |
| Noncardiac ICU | 33 (55.9) | 23 (56.1) | |
| Duration of amiodarone use in hospital (d) | 13.0 ± 13.5 | 12.0 ± 12.0 | .176 |
| Amiodarone was continued on medicine floor | 53 (89.8) | 22 (53.7) | <.001 |
Values are number (percentage) or median (interquartile range).
AMS = altered mental status; ICU = intensive care unit; TIA = transient ischemic attack.
Discussion
The results of our study showed that among patients initiated on amiodarone for NAFCI, 23% of patients were continued on amiodarone at hospital discharge, potentially for long-term use, without an assessment by or referral to a cardiologist. This raises significant concern for the development of adverse effects, increased healthcare costs, and the unnecessary prescription. Amiodarone therapy also carries risk of new drug–drug interactions and QTc prolongation.
Currently there are few data available regarding the optimal duration of amiodarone use for NAFCI. Hughes et al
6
recommended limiting amiodarone use in critically ill patients to 48 hours unless absolutely necessary, owing to the potential adverse reactions associated with its prolonged use. In contrast, Gillinov et al7
evaluated rate control versus rhythm control for postoperative AF, for which use of amiodarone for 60 days was recommended. Although the duration of amiodarone use in critically ill patient is uncertain, our study found that the majority of patients had converted back to normal sinus rhythm regardless of duration of amiodarone.The failure to deprescribe medications intended for short-term inpatient use has been described previously. Recent retrospective studies found that patients who were prescribed antipsychotics for the management of ICU delirium were receiving prescriptions for continued therapy upon discharge, despite resolution of delirium.
8
, 9
Another study, by MacMillan et al,10
identified the unnecessary continuation of docusate despite its known ineffectiveness. These studies emphasize the importance of medication reconciliation at all points of transitions of care. Suggested tools to prevent this include electronic prompts in the medical record, clear documentation of the indications for prescribing, thorough discharge summaries, transition of care specialists, multidisciplinary assessment of medications prescribed before discharge, and regular communication with the multidisciplinary team, patients, and families.Our study has some limitations. First, we assumed that adequate follow-up with a cardiologist would be essential to determine the duration of therapy and prevent serious complications from long-term use of amiodarone. Second, this study was a single-center retrospective review with a small number of patients. Some information obtained from the medical record might be missing, such as verbal instructions to limit the duration of the prescription or referral to a specialist.
Conclusion
The prescription of amiodarone, originally initiated for NAFCI, was continued upon discharge without cardiology referral in 23% of patients at this university hospital. This may contribute to the development of adverse effects and increased healthcare costs associated with an unnecessary prescription of a high-risk medication. Strategies must be in place to prevent the continuation of all medications originally intended for short-term inpatient use.
Acknowledgments
We thank Thammasin Ingviya, MD, for assistance with statistical analysis.
References
- Epidemiology, prevention, and treatment of new-onset atrial fibrillation in critically ill: a systematic review.J Intensive Care. 2015; 3: 19
- Incidence and prognostic impact of new-onset atrial fibrillation in patients with septic shock: a prospective observational study.Crit Care. 2010; 14: R108
- Cardiac arrhythmias in critically ill patients: epidemiologic study.Crit Care Med. 1990; 18: 1383-1388
- Clinical review: treatment of new-onset atrial fibrillation in medical intensive care patients–a clinical framework.Crit Care. 2007; 11: 233
- Cordarone [package insert].Wyeth Pharmaceuticals, Philadelphia2004
- Intravenous amiodarone in intensive care. Time for a reappraisal?.Intensive Care Med. 2000; 26: 1730-1739
- Rate control versus rhythm control for atrial fibrillation after cardiac surgery.N Engl J Med. 2016; 374: 1911-1921
- Hospital delirium treatment: continuation of antipsychotic therapy from the intensive care unit to discharge.Am J Health Syst Pharm. 2015; 72: S133-S139
- Evaluation of discontinuation of atypical antipsychotics prescribed for ICU delirium.J Pharm Pract. 2013; 26: 253-256
- Missed opportunity to deprescribe: docusate for constipation in medical inpatients.Am J Med. 2016; 129: 1001.e1-1001.e7
Article info
Publication history
Published online: March 23, 2017
Footnotes
Funding: None.
Conflict of Interest: None.
Authorship: All authors had access to the data and a role in writing the manuscript.
Identification
Copyright
© 2017 Elsevier Inc. All rights reserved.
