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Schroeder, Darrell

0000-0001-8591-5936

Mayo Clinic

Division of Biostatistics, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA.

Citations 171

Antiproteinase 3 Antineutrophil Cytoplasmic Antibodies and Disease Activity in Wegener Granulomatosis

Annals of Internal Medicine | April 12, 2013 | Volume: 147 | Issue: 9 | Pages: 611-619

10.7326/0003-4819-147-9-200711060-00005 | PMID 17975183

Polymyositis–Dermatomyositis-associated Interstitial Lung Disease

American Journal of Respiratory and Critical Care Medicine | April 4, 2013 | Volume: 164 | Issue: 7 | Pages: 1182-1185

10.1164/ajrccm.164.7.2103110 | PMID 11673206

Abstract We report findings in 70 patients with both diffuse interstitial lung disease and either polymyositis (PM) or dermatomyositis (DM). Initial presentations were most commonly either musculoskeletal (arthralgias, myalgias, and weakness) or pulmonary (cough, dyspnea, and fever) symptoms alone; in only 15 patients (21.4%) did both occur simultaneously. Pulmonary disease usually took the form of acute to subacute antibiotic-resistant community-acquired pneumonia. Chest radiographs and computed tomography most commonly demonstrated bilateral irregular linear opacities involving the lung bases; occasionally consolidation was present. Jo-1 antibody was present in 19 (38%) of 50 patients tested. Synchronous associated malignancy was present in 4 of 70 patients (5.7%). Surgical lung biopsies disclosed nonspecific interstitial pneumonia (NSIP) in 18 of 22 patients (81.8%), organizing diffuse alveolar damage (DAD) in 2, bronchiolitis obliterans organizing pneumonia (BOOP) in 1, and usual interstitial pneumonia (UIP) in 1. Treatment usually included prednisone in 40–60 mg/d dosages for initial control, followed by lower dose prednisone plus an immunosuppressive agent such as azathioprine or methotrexate for disease suppression. Survival was significantly better than that observed for historical control subjects with idiopathic UIP, and was more consistent with survival previously reported in idiopathic NSIP. There was no difference in survival between Jo-1 positive and Jo-1 negative groups.
Idiopathic Pulmonary Fibrosis: Impact of Oxygen and Colchicine, Prednisone, or No Therapy on Survival

American Journal of Respiratory and Critical Care Medicine | April 4, 2013 | Volume: 161 | Issue: 4 | Pages: 1172-1178

10.1164/ajrccm.161.4.9907002 | PMID 10764308

Abstract The clinical records of 487 patients seen at Mayo Clinic Rochester (MCR) during 1994 through 1996 who were diagnosed as having idiopathic pulmonary fibrosis of the usual interstitial pneumonia type (IPF/UIP) were reviewed. Computed tomography (CT) had been done in 94.7% of patients and surgical open lung biopsy (OLB) in 20.3%. Median survival was 3.2 yr. We compared survival as a function of treatment program, based on intent to treat at the time of the initial contact within the study window. Treatment advised included colchicine alone in 167, no therapy in 157, prednisone at maintenance dosages alone in 54, colchicine plus prednisone in 71, and other programs in 38. Oxygen therapy was advised in 133 patients. By univariate analysis, worse survival was associated with prednisone therapy compared with no therapy, and with oxygen therapy compared with no oxygen therapy. However, on multivariate analysis, worse survival was associated with older age, male gender, lower diffusing capacity for carbon monoxide (DlCO), lower alveolar volume (Va), and a history of worsening pulmonary function. When adjustment was made for these factors, there was no significant difference in survival between those patients treated with colchicine or prednisone and those on no therapy, and no difference between those on oxygen therapy and those without oxygen.
Prognostic Significance of Histopathologic Subsets in Idiopathic Pulmonary Fibrosis

American Journal of Respiratory and Critical Care Medicine | April 4, 2013 | Volume: 157 | Issue: 1 | Pages: 199-203

10.1164/ajrccm.157.1.9704130 | PMID 9445300

Abstract Idiopathic pulmonary fibrosis (IPF) is a generally fatal disorder with a reported median survival of 3 to 6 yr. This has been based on relatively few studies with diagnoses inconsistently confirmed by adequate lung biopsy. Retrospective analysis of 104 patients with IPF who had open lung biopsy (OLB) at Mayo Medical Center from 1976 to 1985 was performed to establish the overall survival rate, the spectrum of histopathological subgroups and their associated prognostic significance. The study group consisted of 54 men and 50 women with a median age of 63 yr. Median survival was 3.8 yr after diagnosis by OLB with an estimated 10 yr survival of 27%. Current histopathologic review showed a heterogeneous group including usual interstitial pneumonia (UIP), desquamative interstitial pneumonia (DIP), nonspecific interstitial pneumonia/fibrosis (NSIP), acute interstitial pneumonia (AIP), bronchiolitis, bronchiolitis obliterans organizing pneumonia (BOOP), and others. Median survival of the UIP group was 2.8 yr which is significantly worse (p < 0.001) than for other subgroups of chronic interstitial pneumonias. IPF includes several histopathologic subgroups with significantly different survival rates. Patients with UIP have worse survival than patients with other types of idiopathic chronic interstitial pneumonias including NSIP. Accurate histopathologic classification is essential for prognostication in patients with IPF.
S -Adenosyl- l -Methionine (SAMe) for Smoking Abstinence: A Randomized Clinical Trial

The Journal of Alternative and Complementary Medicine | August 17, 2012 | Volume: 18 | Issue: 9 | Pages: 854-859

10.1089/acm.2011.0462 | PMID 22901308

Effect of General Anesthesia in Patients With Cerebral Palsy at the Turn of the New Millennium

Journal of Child Neurology | December 21, 2011 | Volume: 27 | Issue: 7 | Pages: 859-866

10.1177/0883073811428378 | PMID 22190505

The severity of preoperative cerebral palsy appears to correlate directly with postoperative complications. The primary aim of this study was to characterize the frequency of perioperative morbidity and mortality in cerebral palsy patients undergoing anesthesia. This was accomplished by undertaking a systematic review of the Mayo Database. The risk for perioperative adverse events was 63.1% (95% confidence interval 59.8%-66.5%). However, it deserves clarification that hypothermia and clinically significant yet non–life-threatening hypotension represented the majority (80%) of these complications. When these 2 events are excluded, the rate of adverse perioperative events was 13.1% (95% confidence interval 10.8%-15.5%). Risk factors associated with increased risk included American Society of Anesthesiologists physical status score exceeding 2, history of seizures, upper airway hypotonia, general surgery procedures, and adults. Our findings are useful to counsel patients with cerebral palsy, their caregivers, and their guardians regarding the risk of general anesthesia.
Perioperative Nerve Injury after Total Hip Arthroplasty

Anesthesiology | October 4, 2011 | Volume: 115 | Issue: 6 | Pages: 1172-1178

10.1097/aln.0b013e3182326c20 | PMID 21934486

Background Perioperative nerve injury (PNI) is a recognized complication of total hip arthroplasty (THA). Regional anesthesia (RA) techniques may increase the risk of neurologic injury. Using a retrospective cohort study, the authors tested the hypothesis that use of RA increases the risk for PNI after elective THA. Methods All adult patients who underwent elective THA at Mayo Clinic during a 20-yr period were included. The primary outcome was the presence of a new PNI within 3 months of surgery. Multivariable logistic regression was used to evaluate patient, surgical, and anesthetic risk factors for PNI. Results Of 12,998 patients undergoing THA, 93 experienced PNI (incidence = 0.72%; 95% CI 0.58-0.88%). PNI was not associated with type of anesthesia (OR = 0.72 for neuraxial-combined vs. general; 95% CI 0.46-1.14) or peripheral nerve blockade (OR = 0.65; 95% CI 0.34-1.21). The risk for PNI was associated with younger age (OR = 0.79 per 10-yr increase; 95% CI 0.69-0.90), female gender (OR = 1.72; 95% CI 1.12-2.64), longer operations (OR = 1.10 per 30-min increase; 95% CI 1.03-1.18) or posterior surgical approach (OR = 1.91 vs. anterior approach; 95% CI 1.22-2.99). Neurologic recovery was not influenced by the use of RA techniques in patients with PNI. Conclusions The risk for PNI after THA was not increased with the use of neuraxial anesthesia or peripheral nerve blockade. Neurologic recovery in patients who experienced PNI was not affected by the use of RA. These results support the use of RA techniques in patients undergoing elective THA given their known functional and clinical benefits.
Cognitive and Behavioral Outcomes After Early Exposure to Anesthesia and Surgery

Pediatrics | October 4, 2011 | Volume: 128 | Issue: 5 | Pages: e1053-e1061

10.1542/peds.2011-0351 | PMID 21969289

BACKGROUND:Annually, millions of children are exposed to anesthetic agents that cause apoptotic neurodegeneration in immature animals. To explore the possible significance of these findings in children, we investigated the association between exposure to anesthesia and subsequent (1) learning disabilities (LDs), (2) receipt of an individualized education program for an emotional/behavior disorder (IEP-EBD), and (3) scores of group-administered achievement tests.METHODS:This was a matched cohort study in which children (N = 8548) born between January 1, 1976, and December 31, 1982, in Rochester, Minnesota, were the source of cases and controls. Those exposed to anesthesia (n = 350) before the age of 2 were matched to unexposed controls (n = 700) on the basis of known risk factors for LDs. Multivariable analysis adjusted for the burden of illness, and outcomes including LDs, receipt of an IEP-EBD, and the results of group-administered tests of cognition and achievement were outcomes.RESULTS:Exposure to multiple, but not single, anesthetic/surgery significantly increased the risk of developing LDs (hazard ratio: 2.12 [95% confidence interval: 1.26–3.54]), even when accounting for health status. A similar pattern was observed for decrements in group-administered tests of achievement and cognition. However, exposure did not affect the rate of children receiving an individualized education program.CONCLUSIONS:Repeated exposure to anesthesia and surgery before the age of 2 was a significant independent risk factor for the later development of LDs but not the need for educational interventions related to emotion/behavior. We cannot exclude the possibility that multiple exposures to anesthesia/surgery at an early age may adversely affect human neurodevelopment with lasting consequence.
Clinician-delivered Intervention to Facilitate Tobacco Quitline Use by Surgical Patients

Anesthesiology | February 11, 2011 | Volume: 114 | Issue: 4 | Pages: 847-855

10.1097/aln.0b013e31820d868d | PMID 21317630

Background Telephone quitlines that provide counseling support are efficacious in helping cigarette smokers quit and have been widely disseminated; currently, they are underused. Surgery represents a teachable moment for smoking cessation, which can benefit surgical outcomes; however, few surgical patients receive smoking cessation interventions. This study developed and tested a clinician-delivered intervention to facilitate quitline use by adult patients scheduled for elective surgery. Methods After formative work involving patients and clinicians, a brief intervention was designed to facilitate telephone quitline use. It was then evaluated in a randomized trial of 300 adults scheduled for elective surgery. A control standard brief stop-smoking intervention served as a comparator, with both interventions delivered by clinicians. The primary outcome was the use rate of a quitline accessed through a dedicated toll-free telephone number, with use defined as completing at least one full counseling session. Secondary outcomes included self-reported abstinence from cigarettes at 30 and 90 days postoperatively. Results Subject characteristics were similar between the two groups. Records from the designated quitline documented that 29 of 149 subjects (19.5%) in the quitline intervention group and 0 of 151 subjects in the control group completed the first full counseling session (P < 0.0001). There were no significant differences in the self-reported point-prevalent and continuous abstinence rates between groups at either 30 or 90 days postoperatively, although rates tended to be higher in the quitline intervention group. Conclusions Clinicians can effectively facilitate quitline use by surgical patients. Further work is necessary to evaluate the efficacy of this approach in terms of long-term abstinence from cigarette smoking.
Perioperative Nerve Injury after Total Knee Arthroplasty

Anesthesiology | January 15, 2011 | Volume: 114 | Issue: 2 | Pages: 311-317

10.1097/aln.0b013e3182039f5d | PMID 21239974

Background Perioperative nerve injury (PNI) is one of the most debilitating complications after total knee arthroplasty (TKA). Although regional anesthesia (RA) techniques reduce pain and improve functional outcomes after TKA, they may also contribute to PNI. The objective of this study was to test the hypothesis that PNI risk differs among patients according to RA use during TKA. Methods All patients aged at least 18 yr who underwent elective TKA from January 1988 to July 2007 were retrospectively identified. The primary outcome variable was the presence of a new PNI documented within 3 months of the procedural date. Age, sex, body mass index, type of procedure, tourniquet time, type of anesthesia, and use of peripheral nerve blockade were evaluated as potential risk factors for PNI using multivariable logistic regression. Results Ninety-seven cases of PNI were identified among 12,329 patients. Overall incidence of PNI was 0.79% (95% CI, 0.64-0.96%). PNI was not associated with peripheral nerve blockade (odds ratio [OR], 0.97) or type of anesthesia (OR, 1.10 [neuraxial vs. general]; OR, 1.82 [combined vs. general]). Risk for PNI decreased with age (OR, 0.68 [per decade]; P < 0.001) but increased with tourniquet time (OR, 1.28 [per 30-min increase]; P = 0.003) and bilateral procedures (OR, 2.51; P < 0.001). Patients with PNI who underwent peripheral nerve blockade were less likely to have complete neurologic recovery (OR, 0.37; P = 0.03). Conclusions Risk for PNI after TKA was unchanged by the use of RA techniques. This finding supports the notion that the known benefits of RA for patients undergoing TKA can be achieved without increasing risk of neurologic injury. However, in rare situations when PNI occurs, complete recovery may be less likely if it develops after peripheral nerve blockade.