Abstract ID: A9
Abstract Title: Infleunce of Epidural Analgesia in Medicare Patients Undergoing Total Knee Replacement
Poster Type: Discussion
ABSTRACT BODY
Introduction:
Use of epidural analgesia (EA) may confer some physiologic advantages which may result in decreased morbidity in patients undergoing orthopedic procedures[1]; however, previous Medicare data analysis on patients undergoing total hip replacement revealed no advantage of the perioperative use of EA in decreasing postoperative morbidity and mortality[2]. We applied a newer, more robust Medicare dataset to examine if there was an association of EA and morbidity/mortality in patients undergoing a similar procedure.
Materials and Methods:
A 5% nationally random sample of Medicare beneficiaries from 1997-2001 was analyzed to identify patients undergoing total knee replacement or revision of a total knee replacement (ICD-9 codes 81.54 and 81.55). Patients were divided into two groups depending on the presence or absence of postoperative EA based on the presence of the CPT code 01996. Emergency surgical cases were excluded. Baseline characteristics (demographic and cormorbidities[3]) were compared. The rate of major morbidity (acute myocardial infarction, angina, cardiac dysrhythmias, heart failure, pneumonia, pulmonary edema, respiratory failure, deep venous thrombosis, pulmonary embolism, sepsis, acute renal failure, somnolence, acute cerebrovascular event, transient organic syndrome, and paralytic ileus) and death at 7 and 30 days following the procedure were compared. Multivariate regression analysis incorporating race, gender, age, comorbidities, hospital size, hospital teaching status, and hospital technology status was performed to determine if the presence of EA had an independent effect on mortality or major morbidity.
Results:
Multivariate regression analysis revealed that there was no difference between the groups with regard to overall major morbidity at 7 days after surgery or mortality at both 7 and 30 days after surgery; however, the presence of EA was associated with a significantly higher odds of cardiac dysryhthmias, pneumonia, and somnolence at 30 days after surgery.
Discussion:
The use of postoperative EA was not associated a lower incidence of mortality or major morbidity in Medicare patients undergoing elective total knee replacement or revision of a total knee replacement. On the contrary, EA was associated with significantly higher odds of cardiac dysryhthmias, pneumonia, and somnolence albeit at 30 days after surgery. This contrasts prior RCT data showing a decrease in pulmonary complications with EA[4,5] and experimental data demonstrating physiologic benefits of EA[6,7]. Similar to that in a prior study of Medicare patients[2], there were no differences in mortality between the groups.
References:
1. Rodgers A et al. BMJ 2000;321:1493-6
2. Wu CL et al. Reg Anesth Pain Med 2003;28:271-8
3. Elixhauser A et al. Med Care 1998;36:8-27
4. Ballantyne JC et al. Anesth Analg 1998;86:598-612
5. Rigg JR et al. Lancet 2000;359:1276-82
6. Wu CL et al. Anesth Analg 2000;91:1232-42
7. Liu S et al. Anesthesiology 1995;82:1474-506
ATTACHED FILES
A9_ASRA-01996-TKR-table.doc
Reg Anesth Pain Med 2004; 29(2):A9