Ottokar Stundner

Perioperative Comparative Effectiveness of Anesthetic Technique in Orthopedic Patients

Background:The impact of anesthetic technique on perioperative outcomes remains controversial. We studied a large national sample of primary joint arthroplasty recipients and hypothesized that neuraxial anesthesia favorably influences perioperative outcomes. Methods:Data from approximately 400 hospitals between 2006 and 2010 were accessed. Patients who underwent primary hip or knee arthroplasty were identified and subgrouped by anesthesia technique: general, neuraxial, and combined neuraxial–general. Demographics, postoperative complications, 30-day mortality, length of stay, and patient cost were analyzed and compared. Multivariable analyses were conducted to identify the independent impact of choice of anesthetic on outcomes. Results:Of 528,495 entries of patients undergoing primary hip or knee arthroplasty, information on anesthesia type was available for 382,236 (71.4%) records. Eleven percent were performed under neuraxial, 14.2% under combined neuraxial–general, and 74.8% under general anesthesia. Average age and comorbidity burden differed modestly between groups. When neuraxial anesthesia was used, 30-day mortality was significantly lower (0.10, 0.10, and 0.18%; P < 0.001), as was the incidence of prolonged (>75th percentile) length of stay, increased cost, and in-hospital complications. In the multivariable regression, neuraxial anesthesia was associated with the most favorable complication risk profile. Thirty-day mortality remained significantly higher in the general compared with the neuraxial or neuraxial–general group for total knee arthroplasty (adjusted odds ratio [OR] of 1.83, 95% CI 1.08–3.1, P = 0.02; OR of 1.70, 95% CI 1.06–2.74, P = 0.02, respectively). Conclusions:The utilization of neuraxial versus general anesthesia for primary joint arthroplasty is associated with superior perioperative outcomes. More research is needed to study potential mechanisms for these findings.

Inpatient falls after total knee arthroplasty: the role of anesthesia type and peripheral nerve blocks.

Background:Much controversy remains on the role of anesthesia technique and peripheral nerve blocks (PNBs) in inpatient falls (IFs) after orthopedic procedures. The aim of the study is to characterize cases of IFs, identify risk factors, and study the role of PNB and anesthesia technique in IF risk in total knee arthroplasty patients. Methods:The authors selected total knee arthroplasty patients from the national Premier Perspective database (Premier Inc., Charlotte, NC; 2006–2010; n = 191,570, >400 acute care hospitals). The primary outcome was IF. Patient- and healthcare system–related characteristics, anesthesia technique, and presence of PNB were determined for IF and non-IF patients. Independent risk factors for IFs were determined by using conventional and multilevel logistic regression. Results:Overall, IF incidence was 1.6% (n = 3,042). Distribution of anesthesia technique was 10.9% neuraxial, 12.9% combined neuraxial/general, and 76.2% general anesthesia. PNB was used in 12.1%. Patients suffering IFs were older (average age, 68.9 vs. 66.3 yr), had higher comorbidity burden (average Deyo index, 0.77 vs. 0.66), and had more major complications, including 30-day mortality (0.8 vs. 0.1%; all P < 0.001). Use of neuraxial anesthesia (IF incidence, 1.3%; n = 280) had lower adjusted odds of IF compared with adjusted odds of IF with the use of general anesthesia alone (IF incidence, 1.6%; n = 2,393): odds ratio, 0.70 (95% CI, 0.56–0.87). PNB was not significantly associated with IF (odds ratio, 0.85 [CI, 0.71–1.03]). Conclusions:This study identifies several risk factors for IF in total knee arthroplasty patients. Contrary to common concerns, no association was found between PNB and IF. Further studies should determine the role of anesthesia practices in the context of fall-prevention programs.

The impact of sleep apnea on postoperative utilization of resources and adverse outcomes.

BACKGROUND:Despite the concern that sleep apnea (SA) is associated with increased risk for postoperative complications, a paucity of information is available regarding the effect of this disorder on postoperative complications and resource utilization in the orthopedic population. With an increasing number of surgical patients suffering from SA, this information is important to physicians, patients, policymakers, and administrators alike. METHODS:We analyzed hospital discharge data of patients who underwent total hip or knee arthroplasty in approximately 400 U.S. Hospitals between 2006 and 2010. Patient, procedure, and health care system-related demographics and outcomes such as mortality, complications, and resource utilization were compared among groups. Multivariable logistic regression models were fit to assess the association between SA and various outcomes. RESULTS:We identified 530,089 entries for patients undergoing total hip and knee arthroplasty. Of those, 8.4% had a diagnosis code for SA. In the multivariate analysis, the diagnosis of SA emerged as an independent risk factor for major postoperative complications (OR 1.47; 95% confidence interval [CI], 1.39–1.55). Pulmonary complications were 1.86 (95% CI, 1.65–2.09) times more likely and cardiac complications 1.59 (95% CI, 1.48–1.71) times more likely to occur in patients with SA. In addition, SA patients were more likely to receive ventilatory support, use more intensive care, stepdown and telemetry services, consume more economic resources, and have longer lengths of hospitalization. CONCLUSIONS:The presence of SA is a major clinical and economic challenge in the postoperative period. More research is needed to identify SA patients at risk for complications and develop evidence-based practices to aid in the allocation of clinical and economic resources.

Sleep apnea and total joint arthroplasty under various types of anesthesia: a population-based study of perioperative outcomes.

Background and Objectives The presence of sleep apnea (SA) among surgical patients has been associated with significantly increased risk of perioperative complications. Although regional anesthesia has been suggested as a means to reduce complication rates among SA patients undergoing surgery, no data are available to support this association. We studied the association of the type of anesthesia and perioperative outcomes in patients with SA undergoing joint arthroplasty. Methods Drawing on a large administrative database (Premier Inc), we analyzed data from approximately 400 hospitals in the United States. Patients with a diagnosis of SA who underwent primary hip or knee arthroplasty between 2006 and 2010 were identified. Perioperative outcomes were compared between patients receiving general, neuraxial, or combined neuraxial-general anesthesia. Results We identified 40,316 entries for unique patients with a diagnosis for SA undergoing primary hip or knee arthroplasty. Of those, 30,024 (74%) had anesthesia-type information available. Approximately 11% of cases were performed under neuraxial, 15% under combined neuraxial and general, and 74% under general anesthesia. Patients undergoing their procedure under neuraxial anesthesia had significantly lower rates of major complications than did patients who received combined neuraxial and general or general anesthesia (16.0%, 17.2%, and 18.1%, respectively; P = 0.0177). Adjusted risk of major complications for those undergoing surgery under neuraxial or combined neuraxial-general anesthesia compared with general anesthesia was also lower (odds ratio, 0.83 [95% confidence interval, 0.74–0.93; P = 0.001] vs odds ratio, 0.90 [95% confidence interval, 0.82–0.99; P = 0.03]). Conclusions Barring contraindications, neuraxial anesthesia may convey benefits in the perioperative outcome of SA patients undergoing joint arthroplasty. Further research is needed to enhance an understanding of the mechanisms by which neuraxial anesthesia may exert comparatively beneficial effects.

Comparative perioperative outcomes associated with neuraxial versus general anesthesia for simultaneous bilateral total knee arthroplasty.

Background and Objectives The influence of the type of anesthesia on perioperative outcomes after bilateral total knee arthroplasty (BTKA) remains unknown. Therefore, we examined a large sample of BTKA recipients, hypothesizing that neuraxial anesthesia would favorably impact on outcomes. Methods We identified patient entries indicating elective BTKA between 2006 and 2010 in a national database; subgrouped them by type of anesthesia: general (G), neuraxial (N), or combined neuraxial-general (NG); and analyzed differences in demographics and perioperative outcomes. Results Of 15,687 identified procedures, 6.8% (n = 1066) were performed under N, 80.1% (n = 12,567) under G, and 13.1% (n = 2054) under NG. Comparing N to G and NG, patients in group N were, on average, younger (63.9, 64.6, and 64.8 years; P = 0.030) but did not differ in overall comorbidity burden. Patients in group N required blood product transfusions significantly less frequently (28.5%, 44.7%, 38.0%; P < 0.0001). In-hospital mortality, 30-day mortality, and complication rates tended to be lower in group N, without reaching statistical significance. After adjusting for covariates, N and NG were associated with 16.0% and 6.0% reduction in major complications compared with G, but only the reduced odds for the requirement of blood transfusions associated with N reached statistical significance (N vs G: odds ratio, 0.52 [95% CI, 0.45–0.61], P < 0.0001; NG vs G: odds ratio, 0.77 [95% CI, 0.69–0.86], P < 0.0001). Conclusions Neuraxial anesthesia for BTKA is associated with significantly lower rates of blood transfusions and, by trend, decreased morbidity. Although by itself the effect may be limited, N might be used within a multimodal approach to reduce complications after BTKA.

Demographics and Perioperative Outcome in Patients with Depression and Anxiety Undergoing Total Joint Arthroplasty: A Population-Based Study

BACKGROUND Depression and anxiety are highly prevalent psychiatric disorders. However, little is known about their impact on outcomes in the perioperative setting. This study is intended to gain insight into epidemiology and effects on perioperative morbidity, mortality, length of hospital stay, discharge and cost. METHODS We obtained the National Inpatient Sample from the Hospital Cost and Utilization Project for each year between 2000 and 2008. Entries indicating the performance of primary total hip and knee arthroplasty were identified and separated into four groups: (1) those with concomitant diagnosis of depression or (2) anxiety, (3) both, and (4) none of these diagnoses. The incidence of major complications, non-routine discharge, length, and cost of hospitalization were assessed. Regression analysis was performed to identify if psychiatric comorbidity was an independent risk factor for each outcome. RESULTS We identified 1,212,493 patients undergoing arthroplasty between 2000 and 2008. The prevalence of depression and anxiety significantly increased over time. Patients with either condition had higher hospital charges, rates of non-routine discharges and comorbidity index. Depression or anxiety were associated with significantly decreased adjusted odds for in-hospital mortality (OR = 0.53, p = 0.0147; OR = 0.58, p = 0.0064). The risk of developing a major complication was slightly lower in patients with depression, anxiety or both (OR=0.95, p = 0.0738; OR = 0.95, p = 0.0259; OR = 0.94, p = 0.7349). CONCLUSIONS Patients suffering from depression, anxiety, or both require more healthcare resources in a perioperative setting. However, lower short-term mortality in spite of higher comorbidity burden and without extensive changes in perioperative complication profile indicates better outcome for this group of patients.

Utilization of Critical Care Services among Patients Undergoing Total Hip and Knee Arthroplasty: Epidemiology and Risk Factors

Background: A paucity of data exist on the use of critical care services (CCS) among hip and knee arthroplasty patients. The authors sought to identify the incidence and risk factors for the use of CCS among these patients and compare the characteristics and outcomes of patients who require CCS to those who do not. Methods: The authors analyzed hospital discharge data of patients who underwent primary hip or knee arthroplasty in approximately 400 United States hospitals between 2006 and 2010. Patient and healthcare system-related demographics for admitted patients requiring CCS were compared with those who did not. Differences in outcomes, including mortality, complications, disposition status, and hospital charges, were analyzed. Regression analysis was performed to identify risk factors for requiring CCS. Results: A total of 528,495 patients underwent primary total hip (n = 172,467, 33%) and knee arthroplasty (n = 356,028, 67%). Of these, 3% required CCS. On average, CCS patients were older and had a higher comorbidity burden than did patients not requiring CCS. CCS patients experienced more complications, had longer hospital stays and higher costs, and were less likely to be discharged home than were non-CCS patients. Risk factors with increased odds for requiring CCS included advanced age, use of general versus neuraxial anesthesia, and the presence of postoperative cardiopulmonary complications. Conclusions: Approximately 1 of 30 patients undergoing total joint arthroplasty requires CCS. Given the large number of these procedures performed annually, anesthesiologists, orthopedic surgeons, critical care physicians, and administrators should be aware of the attendant risks this population represents and allocate resources accordingly.

An analysis of the safety of epidural and spinal neuraxial anesthesia in more than 100,000 consecutive major lower extremity joint replacements.

Background and Objectives A feared complication of spinal or epidural anesthesia is the development of epidural or spinal hematoma with subsequent neural element compression. Most available data are derived from the obstetric literature. Little is known about the frequency of hematoma occurrence among patients undergoing orthopedic joint arthroplasty, who are usually elderly and experience significant comorbidities. We sought to study the incidence of clinically significant lesions after spinal and epidural anesthesia and further describe their nature. Methods We retrospectively analyzed a database of all patients who underwent total hip or total knee arthroplasty under neuraxial anesthesia at our institution between January 2000 and October 2010. Patients with radiographically confirmed epidural lesions were identified and further analyzed. Results A total of 100,027 total knee and hip replacements under neuraxial anesthesia were performed at our institution. Ninety-seven patients underwent imaging studies to evaluate perioperative neurologic deficits (0.96/1000; 95% confidence interval, 0.77–1.16/1000). Eight patients were identified with findings of an epidural blood or gas collection (0.07/1000; 95% confidence interval, 0.02–0.13/1000). No patients receiving only spinal anesthesia were affected. All patients diagnosed with hematoma took at least 1 drug that potentially impaired coagulation (5 nonsteroidal anti-inflammatory agents, 1 a tricyclic antidepressant, and 1 an antiplatelet drug). No patient incurred persistent nerve damage. Conclusions The incidence of epidural/spinal complications found in this consecutive case series is relatively low but higher than previously reported in the nonobstetric population. Further research using large data sets could quantify the significance of some of the potentially contributing factors observed in this study.

Rheumatoid Arthritis vs Osteoarthritis in Patients Receiving Total Knee Arthroplasty: Perioperative Outcomes

There is a paucity of data available on perioperative outcomes of patients undergoing total knee arthroplasty (TKA) for rheumatoid arthritis (RA). We determined differences in demographics and risk for perioperative adverse events between patients suffering from osteoarthritis (OA) versus RA using a population-based approach. Of 351,103 entries for patients who underwent TKA, 3.4% had a diagnosis of RA. RA patients were on average younger [RA: 64.3 years vs OA: 66.6 years; P<0.001] and more likely female [RA: 79.2% vs OA: 63.2%; P<0. 001]. The unadjusted rates of mortality and most major perioperative adverse events were similar in both groups, with the exception of infection [RA: 4.5% vs. OA: 3.8%; P<0.001]. RA was not associated with increased adjusted odds for combined adverse events.

Perioperative outcomes and type of anesthesia in hip surgical patients: An evidence based review.

Over the last decades the demand for hip surgery, be it elective or in a traumatic setting, has greatly increased and is projected to expand even further. Concurrent with demographic changes the affected population is burdened by an increase in average comorbidity and serious complications. It has been suggested that the choice of anesthesia not only affects the surgery setting but also the perioperative outcome as a whole. Therefore different approaches and anesthetic techniques have been developed to offer individual anesthetic and analgesic care to hip surgery patients. Recent studies on comparative effectiveness utilizing population based data have given us a novel insight on anesthetic practice and outcome, showing favorable results in the usage of regional vs general anesthesia. In this review we aim to give an overview of anesthetic techniques in use for hip surgery and their impact on perioperative outcome. While there still remains a scarcity of data investigating perioperative outcomes and anesthesia, most studies concur on a positive outcome in overall mortality, thromboembolic events, blood loss and transfusion requirements when comparing regional to general anesthesia. Much of the currently available evidence suggests that a comprehensive medical approach with emphasis on regional anesthesia can prove beneficial to patients and the health care system.