Updated estimates for the burden of chronic limb-threatening ischemia in the Medicare population.

OBJECTIVE: Estimates of chronic limb-threatening ischemia (CLTI) based on diagnosis codes of the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) suggest a prevalence of 0.23%-0.32% and incidence of 0.20%-0.26% among Medicare patients. ICD-10-CM includes 144 CLTI diagnosis codes, allowing improved specificity in identifying affected patients. We sought to use ICD-10-CM diagnosis codes to determine the prevalence of CLTI among Medicare patients and describe the patient cohort affected by this condition. METHODS: Using two years of data from Centers for Medicare and Medicaid Services, we identified all patients that had at least one CLTI diagnosis code to determine prevalence and incidence rates. Sensitivity analyses were performed to compare our methodology to prior publications and quantify the extent of missed diagnoses. The number and type of vascular procedures that occurred after diagnosis were tabulated. A cohort of patients with two or more CLTI diagnosis codes were then identified for further descriptive analysis. Associations between patient demographics and survival were analyzed using Cox proportional hazards models. RESULTS: Over 65 million patients were enrolled in Medicare in 2017 to 2018. Of these, 480,227 had diagnosis of CLTI, with a corresponding to a 1-year incidence of 0.33% and a 2-year prevalence of 0.74%. Patients underwent an average of 43.6 vascular procedures per 100 person-years. Sensitivity analyses identified 89,805 additional patients that had a diagnosis code of peripheral arterial disease who underwent revascularization or amputation. Patients with CLTI were predominantly male (56.2%), white (76.4%), and qualified for Medicare due to age (64.0%). Thirty-seven percent were dual-eligible. One-year survival was 77.7%, significantly lower than estimated actuarial survival adjusted for age, sex, and race (95.1%; P < .001). Cox proportional hazards models demonstrate significantly increased mortality for men vs women (hazard ratio, 1.07; 95% confidence interval, 1.04-1.10; P < .001), but no association between race and overall survival (hazard ratio, 0.99; 95% confidence interval, 0.98-1.01; P = .83). CONCLUSIONS: Using ICD-10-CM diagnosis codes, we demonstrated slightly higher incidence and prevalence of CLTI than in published literature, reflecting our more complete methodology. Sensitivity analyses suggest that increased complexity of the highly specific ICD-10-CM coding may diminish capture of CLTI. Inclusion of patients with non-CLTI peripheral arterial disease diagnoses produces moderate increases in incidence and prevalence at the cost of decreased specificity in identifying patients with CLTI. Medicare patients with CLTI are older, and more commonly male, black, and dual eligible compared with the general Medicare population. Observed mid-term survival for patients with CLTI is significantly lower than actuarial estimates, confirming the importance of focused efforts on identifying and aligning goals of care in this complex patient population.

Poor utilization of palliative care among Medicare patients with chronic limb-threatening ischemia.

OBJECTIVE: Patients with chronic limb-threatening ischemia (CLTI) experience high annual mortality and would benefit from timely palliative care intervention. We sought to better characterize use of palliative care among patients with CLTI in the Medicare population. METHODS: Using Medicare data from 2017 to 2018, we identified patients with CLTI, defined as two or more encounters with a CLTI diagnosis code. Palliative care evaluations were identified using ICD-10-CM Z51.5 "Encounter for palliative care." Time intervals between CLTI diagnosis, palliative consultation, and death or end of follow-up were calculated. Associations between patient demographics, comorbidities, and palliative care consultation were assessed. RESULTS: A total of 12,133 Medicare enrollees with complete data were categorized as having CLTI. Of these, 7.4% (894) underwent a palliative care evaluation at a median of 170 days (interquartile range, 45-352 days) from their CLTI diagnosis. Compared with those who did not undergo evaluation, palliative patients were more likely to be dual eligible for Medicaid (45.2% vs 38.1%; P < .001) and had more comorbid conditions (P < .001). After controlling for gender and race, age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.02-1.04), dual eligibility (OR, 1.40; 95% CI, 1.22-1.62), solid organ malignancy (OR, 2.82; 95% CI, 1.92-4.14), hematologic malignancy (OR, 2.24; 95% CI, 1.27-3.98), congestive heart failure (OR, 1.44; 95% CI, 1.15-1.88), complicated diabetes (OR, 1.35; 95% CI, 1.11-1.65), dementia (OR, 1.32; 95% CI, 1.04-1.66), and severe renal failure (OR, 1.56; 85% CI. 1.24-1.98) were independently associated with palliative care evaluation. During mean follow up of 410 ± 220 days, 16.9% (2044) of patients died at a mean of 268 (±189) days after their CLTI diagnosis. Among living patients, only 3.2% (325) underwent palliative evaluation. Comparatively, 27.8% (569) of patients who died received palliative care at a median of 196 days (interquartile range, 55-362 days) after their diagnosis and 15 days (interquartile range, 5-63 days) prior to death. CONCLUSIONS: Despite high mortality, palliative care services were rarely provided to Medicare patients with CLTI. Age, medical complexity, and income status may play a role in the decision to consult palliative care. When obtained, evaluations occurred closer to time of death than to time of CLTI diagnosis, suggesting misuse of palliative care as end-of-life care.

Optimal Definition of Pancreaticoduodenectomy in the International Classification of Diseases, 10th Revision, Procedure Coding System.

BACKGROUND: The implementation of the International Classification of Diseases, 10th Revision, Procedure Coding System (ICD-10-PCS) has created difficulty in identifying certain procedures, including pancreaticoduodenectomy. We sought to evaluate which combinations of ICD-10-PCS codes best identify pancreaticoduodenectomy. STUDY DESIGN: We used 2017-2018 Medicare data to identify acute care hospitalization claims of beneficiaries with both ICD-10-PCS and Current Procedural Terminology (CPT) codes available. We developed 12 candidate ICD-10-PCS definitions of pancreaticoduodenectomy and evaluated their test characteristics in identifying hospitalizations involving CPT codes 48150, 48152, 48153, 48154, or 48155 as the criterion standard. We selected one candidate definition with the best balance of test characteristics, then performed decision tree analysis and evaluated the conditional marginal sensitivity and positive predictive value of each individual code to understand which were most informative. RESULTS: Among 964,613 hospitalization claims from 4648 hospitals, 385 claims from 217 hospitals involved a CPT code for pancreaticoduodenectomy. The ICD-10-PCS definition with the best balance had a sensitivity of 92.2% (95% CI: 89.2%-94.4%), specificity of 99.9977% (95% CI: 99.9961%-99.9984%), positive predictive value of 93.7% (95% CI: 90.3%-95.9%), and negative predictive value of 99.9969% (95% CI: 99.9955%-99.9978%). The most informative procedure codes involved open nondiagnostic excision or resection of the duodenum (0DB90ZZ and 0DT90ZZ) and pancreas (0FBG0ZZ and 0FTG0ZZ). CONCLUSION: An ICD-10-PCS definition of pancreaticoduodenectomy using codes for (1) open or percutaneous endoscopic excision or resection of the pancreas and (2) similar codes for the duodenum, consistent with coding guidelines, has satisfactory test characteristics. We suggest researchers consider such characteristics in defining pancreaticoduodenectomy using ICD-10-PCS.

Outcomes and risk factors for delayed-onset postoperative respiratory failure: a multi-center case-control study by the University of California Critical Care Research Collaborative (UC3RC).

BACKGROUND: Few interventions are known to reduce the incidence of respiratory failure that occurs following elective surgery (postoperative respiratory failure; PRF). We previously reported risk factors associated with PRF that occurs within the first 5 days after elective surgery (early PRF; E-PRF); however, PRF that occurs six or more days after elective surgery (late PRF; L-PRF) likely represents a different entity. We hypothesized that L-PRF would be associated with worse outcomes and different risk factors than E-PRF. METHODS: This was a retrospective matched case-control study of 59,073 consecutive adult patients admitted for elective non-cardiac and non-pulmonary surgical procedures at one of five University of California academic medical centers between October 2012 and September 2015. We identified patients with L-PRF, confirmed by surgeon and intensivist subject matter expert review, and matched them 1:1 to patients who did not develop PRF (No-PRF) based on hospital, age, and surgical procedure. We then analyzed risk factors and outcomes associated with L-PRF compared to E-PRF and No-PRF. RESULTS: Among 95 patients with L-PRF, 50.5% were female, 71.6% white, 27.4% Hispanic, and 53.7% Medicare recipients; the median age was 63 years (IQR 56, 70). Compared to 95 matched patients with No-PRF and 319 patients who developed E-PRF, L-PRF was associated with higher morbidity and mortality, longer hospital and intensive care unit length of stay, and increased costs. Compared to No-PRF, factors associated with L-PRF included: preexisiting neurologic disease (OR 4.36, 95% CI 1.81-10.46), anesthesia duration per hour (OR 1.22, 95% CI 1.04-1.44), and maximum intraoperative peak inspiratory pressure per cm H20 (OR 1.14, 95% CI 1.06-1.22). CONCLUSIONS: We identified that pre-existing neurologic disease, longer duration of anesthesia, and greater maximum intraoperative peak inspiratory pressures were associated with respiratory failure that developed six or more days after elective surgery in adult patients (L-PRF). Interventions targeting these factors may be worthy of future evaluation.

Do the 2018 Leapfrog Group Minimal Hospital and Surgeon Volume Thresholds for Esophagectomy Favor Specific Patient Demographics?

OBJECTIVE: We examine how esophagectomy volume thresholds reflect outcomes relative to patient characteristics. SUMMARY BACKGROUND DATA: Esophagectomy outcomes are associated with surgeon and hospital operative volumes, leading the Leapfrog Group to recommend minimum annual volume thresholds of 7 and 20 respectively. METHODS: Patients undergoing esophagectomy for cancer were identified from the 2007-2013 New York and Florida Healthcare Cost and Utilization Project's State Inpatient Databases. Logit models adjusted for patient characteristics evaluated in-hospital mortality, complications, and prolonged length of stay (PLOS). Median surgeon and hospital volumes were compared between young-healthy (age 18-57, Elixhauser Comorbidity Index [ECI] <2) and older-sick patients (age ≥71, ECI >4). RESULTS: Of 4330 esophagectomy patients, 3515 (81%) were male, median age was 64 (interquartile range 58-71), and mortality was 4.0%. Patients treated by both low-volume surgeons and hospitals had the greatest mortality risk (5.0%), except in the case of older-sick patients mortality was highest at high-volume hospitals with high-volume surgeons (12%). For mortality <1%, annual hospital and surgeon volumes needed were 23 and 8, respectively; mortality rose to 4.2% when volumes dropped to the Leapfrog thresholds of 20 and 7, respectively. Complication rose from 53% to 63% when hospital and surgeon volumes decreased from 28 and 10 to 19 and 7, respectively. PLOS rose from 19% to 27% when annual hospital and surgeon volumes decreased from 27 and 8 to 20 and 7, respectively. CONCLUSIONS: Current Leapfrog Group esophagectomy volume guidelines may not predict optimal outcomes for all patients, especially at extremes of age and comorbidities.

Injuries Sustained During Incarceration Among Prisoners.

BACKGROUND: The U.S. prison population has increased substantially in recent years, and violent injury is common among prisoners. We sought to describe injury patterns and other characteristics of prisoners who presented to a trauma center after injury. Because penetrating trauma from an improvised weapon (e.g., shank) is frequent, we also sought to compare characteristics and outcomes of prisoners and non-prisoners who sustained an anterior abdominal stab or shank wound (AASW). METHODS: We analyzed injured adult prisoners who presented to a Level 1 trauma center between February, 2011, and April, 2017. We described characteristics of the injured prisoners and their hospitalizations. We compared prisoners who sustained an AASW to a random sample of non-prisoners with the same mechanism of injury using the chi-square test, Student's t-test, and logistic and Poisson regression. RESULTS: Of 14,461 hospitalized injured adults, 299 (2.0%) were injured while incarcerated. 185 (62%) encounters involved interpersonal violence and 36 prisoners (12%) presented with self-inflicted injuries. 98 (33%) had a psychiatric disorder. Among 33 prisoners and 66 non-prisoners who sustained an AASW, prisoners were less likely to have undergone a laparotomy [14/33 (42%) vs 44/66 (67%); RR 0.64 (95% CI 0.41-0.98)] or sustained an injury requiring operative intervention [2/33 (6%) vs 23/66 (35%); RR 0.17 (95% CI 0.04-0.69)]. CONCLUSIONS: Many injured prisoners have psychiatric illness, are involved in interpersonal violence, or harm themselves. Among hospitalized patients, abdominal stab/shank wounds sustained in prison are less likely to result in significant injuries or operative intervention than similar wounds in non-prisoners.

Risk Factors Associated With Early Postoperative Respiratory Failure: A Matched Case-Control Study.

BACKGROUND: Postoperative respiratory failure is the most common serious postoperative pulmonary complication, yet little is known about factors that can reduce its incidence. We sought to elucidate modifiable factors associated with respiratory failure that developed within the first 5 d after an elective operation. MATERIALS AND METHODS: Matched case-control study of adults who had an operation at five academic medical centers between October 1, 2012 and September 30, 2015. Cases were identified using administrative data and confirmed via chart review by critical care clinicians. Controls were matched 1:1 to cases based on hospital, age, and surgical procedure. RESULTS: Our total sample (n = 638) was 56.4% female, 71.3% white, and had a median age of 62 y (interquartile range 51, 70). Factors associated with early postoperative respiratory failure included male gender (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.12-2.63), American Society of Anesthesiologists class III or greater (OR 2.85, 95% CI 1.74-4.66), greater number of preexisting comorbidities (OR 1.14, 95% CI 1.004-1.30), increased operative duration (OR 1.14, 95% CI 1.06-1.22), increased intraoperative positive end-expiratory pressure (OR 1.23, 95% CI 1.13-1.35) and tidal volume (OR 1.13, 95% CI 1.004-1.27), and greater net fluid balance at 24 h (OR 1.17, 95% CI 1.07-1.28). CONCLUSIONS: We found greater intraoperative ventilator volume and pressure and 24-h fluid balance to be potentially modifiable factors associated with developing early postoperative respiratory failure. Further studies are warranted to independently verify these risk factors, explore their role in development of early postoperative respiratory failure, and potentially evaluate targeted interventions.

Use of Statewide Administrative Data to Assess Clinical Outcomes: A Retrospective Cohort Study of Therapeutic Anticoagulation for Isolated Calf Vein Thrombosis.

BACKGROUND: Single-center comparative effectiveness studies evaluating outcomes that can occur posthospitalization may become biased if outcomes diagnosed at other facilities are not ascertained. Administrative datasets that link patients' records across facilities may improve outcome ascertainment. OBJECTIVE: To determine whether use of linked administrative data significantly augments thromboembolic outcome ascertainment. RESEARCH DESIGN: Retrospective cohort study. SUBJECTS: Patients with an acute isolated calf deep vein thrombosis (DVT) diagnosed at 1 Californian center during 2010-2013. MEASURES: Proximal DVT or pulmonary embolism (PE) within 180 days. We ascertained outcomes from linked California hospitalization, emergency department, and ambulatory surgery data and compared this information to outcomes previously identified from review of the center's medical records. RESULTS: Among 384 patients with an isolated calf DVT, 333 could be linked to longitudinal administrative data records. Ten patients had a possible proximal DVT or PE (4 more clearly so) from administrative data; all were unknown from medical record review. Eleven patients with known outcomes from medical record review had no outcome from administrative data. The adjusted odds ratio of proximal DVT or PE with therapeutic anticoagulation attenuated from 0.33 [95% confidence interval (CI), 0.12-0.87] using only medical record review to 0.64 (95% CI, 0.29-1.40) using both medical record review and possible outcomes from administrative data. Restricting the outcome to diagnoses clearly involving proximal DVT or PE, the adjusted odds ratio was 0.46 (95% CI, 0.19-1.10). CONCLUSIONS: Use of linked hospital administrative data augmented detection of outcomes but imperfect linkage, nonspecific diagnoses, and documentation/coding errors introduced uncertainty regarding the accuracy of outcome ascertainment.

Older Adults With Isolated Rib Fractures Do Not Require Routine Intensive Care Unit Admission.

BACKGROUND: Older adults with isolated rib fractures are often admitted to an intensive care unit (ICU) because of presumedly increased morbidity and mortality. However, evidence-based guidelines are limited. We sought to identify characteristics of these patients that predict the need for ICU care. MATERIALS AND METHODS: We analyzed patients ≥50 y old at our center during 2013-2017 whose only indication for ICU admission, if any, was isolated rib fractures. The primary outcome was any critical care intervention (e.g., intubation) or adverse event (e.g., hypoxemia) (CCIE) based on accepted critical care guidelines. We used stepwise logistic regression to identify characteristics that predict CCIEs. RESULTS: Among 401 patients, 251 (63%) were admitted to an ICU. Eighty-three patients (33%) admitted to an ICU and 7 (5%) admitted to the ward experienced a CCIE. The most common CCIEs were hypotension (10%), frequent respiratory therapy (9%), and oxygen desaturation (8%). Predictors of CCIEs included incentive spirometry <1 L (OR 4.72, 95% CI 2.14-10.45); use of a walker (OR 2.86, 95% CI 1.29-6.34); increased chest Abbreviated Injury Scale score (AIS 3 OR 5.83, 95% CI 2.34-14.50); age ≥72 y (OR 2.68, 95% CI 1.48-4.86); and active smoking (OR 2.11, 95% CI 1.06-4.20). CONCLUSIONS: Routine ICU admission is not necessary for most older adults with isolated rib fractures. The predictors we identified warrant prospective evaluation for development of a clinical decision rule to preclude unnecessary ICU admissions.

Lack of persistent microchimerism in contemporary transfused trauma patients.

BACKGROUND: Following transfusion, donor white blood cells (WBCs) can persist long-term in the recipient, a phenomenon termed transfusion-associated microchimerism (TA-MC). Prior studies suggest TA-MC is limited to transfusion following traumatic injury, and is not prevented by leukoreduction. STUDY DESIGN AND METHODS: We conducted a prospective cohort study at a major trauma center to evaluate TA-MC following injury. Index samples were collected upon arrival, prior to transfusion. Follow-up samples were collected at intervals up to one year, and beyond for those testing positive for TA-MC. TA-MC was detected by real-time quantitative allele-specific polymerase chain reaction assays at the HLA-DR locus and several polymorphic insertion deletion sites screening for non-recipient alleles. RESULTS: A total of 378 trauma patients were enrolled (324 transfused cases and 54 non-transfused controls). Mean age was 42 ± 18 years, 74% were male, and 80% were injured by blunt mechanism. Mean Injury Severity Score was 20 ± 12. Among transfused patients, the median (interquartile range) number of red cell units transfused was 6 (3,12), and median time to first transfusion was 9 (0.8,45) hours. Only one case of long-term TA-MC was confirmed in our cohort. We detected short-term TA-MC in 6.5% of transfused subjects and 5.6% on non-transfused controls. CONCLUSIONS: In contrast to earlier studies, persistent TA-MC was not observed in our cohort of trauma subjects. Short-term TA-MC was detected, but at a lower frequency than previously observed, and rates were not significantly different than what was observed in non-transfused controls. The reduction in TA-MC occurrence may be attributable to changes in leukoreduction or other blood processing methods.

NSTI Organisms and Regions: A Multicenter Study From the American Association for the Surgery of Trauma.

BACKGROUND: Conflicting data on the microbiology and epidemiology of necrotizing soft tissue infections (NSTIs) appear to stem from the heterogeneity in microbiology observed in regions across the United States. Our goal was to determine current differences in organism prevalence and outcomes for NSTI and non-necrotizing severe soft tissue infections across the United States. We hypothesized that there were geographical differences in organism prevalence that would lead to differences in outcomes. MATERIALS AND METHODS: This study was a retrospective multi-institutional trial from centers across the United States and Canada. Demographic, clinical, and outcomes data were collected. Bivariate and multivariable analyses were performed to determine the effects of region and microbiology on outcomes. RESULTS: A total of 622 patients were included in this study. Polymicrobial infections (45%) were the most prevalent infections in all regions. On bivariate analysis, Clostridium and polymicrobial infections had higher mean Laboratory Risk Indicator for Necrotizing Fasciitis scores and American Association for the Surgery of Trauma grades (P < 0.001 for both) than other organisms. Patients in the South were more likely to be uninsured and had worse unadjusted outcomes. In a risk-adjusted model, increasing American Association for the Surgery of Trauma grade was predictive of mortality (OR, 2.3; 95% CI, 1.6-3.1; P < 0.001), as was age ≥ 55 y (OR 2.7, 95% CI 1.3-5.3, P = 0.006), but region and organism type were not associated with mortality. CONCLUSIONS: We found important regional differences with respect to organism type and demographics. However, on risk-adjusted models, neither region nor organism type predicted mortality.

Effect of Abdominal Ultrasound on Clinical Care, Outcomes, and Resource Use Among Children With Blunt Torso Trauma: A Randomized Clinical Trial.

Importance: The utility of the focused assessment with sonography for trauma (FAST) examination in children is unknown. Objective: To determine if the FAST examination during initial evaluation of injured children improves clinical care. Design, Setting, and Participants: A randomized clinical trial (April 2012-May 2015) that involved 975 hemodynamically stable children and adolescents younger than 18 years treated for blunt torso trauma at the University of California, Davis Medical Center, a level I trauma center. Interventions: Patients were randomly assigned to a standard trauma evaluation with the FAST examination by the treating ED physician or a standard trauma evaluation alone. Main Outcomes and Measures: Coprimary outcomes were rate of abdominal computed tomographic (CT) scans in the ED, missed intra-abdominal injuries, ED length of stay, and hospital charges. Results: Among the 925 patients who were randomized (mean [SD] age, 9.7 [5.3] years; 575 males [62%]), all completed the study. A total of 50 patients (5.4%, 95% CI, 4.0% to 7.1%) were diagnosed with intra-abdominal injuries, including 40 (80%; 95% CI, 66% to 90%) who had intraperitoneal fluid found on an abdominal CT scan, and 9 patients (0.97%; 95% CI, 0.44% to 1.8%) underwent laparotomy. The proportion of patients with abdominal CT scans was 241 of 460 (52.4%) in the FAST group and 254 of 465 (54.6%) in the standard care-only group (difference, -2.2%; 95% CI, -8.7% to 4.2%). One case of missed intra-abdominal injury occurred in a patient in the FAST group and none in the control group (difference, 0.2%; 95% CI, -0.6% to 1.2%). The mean ED length of stay was 6.03 hours in the FAST group and 6.07 hours in the standard care-only group (difference, -0.04 hours; 95% CI, -0.47 to 0.40 hours). Median hospital charges were $46 415 in the FAST group and $47 759 in the standard care-only group (difference, -$1180; 95% CI, -$6651 to $4291). Conclusions and Relevance: Among hemodynamically stable children treated in an ED following blunt torso trauma, the use of FAST compared with standard care only did not improve clinical care, including use of resources; ED length of stay; missed intra-abdominal injuries; or hospital charges. These findings do not support the routine use of FAST in this setting. Trial Registration: clinicaltrials.gov Identifier: NCT01540318.

Splenectomy and the risk of sepsis: a population-based cohort study.

OBJECTIVE: We sought to estimate the long-term risk of sepsis in patients who underwent splenectomy before, during, and after implementation of vaccination. BACKGROUND: Because patients who have undergone splenectomy are considered at increased risk of bacterial sepsis, they typically receive vaccination, education, and occasionally antibiotic prophylaxis. However, the extent to which these interventions have actually reduced the risk of sepsis remains unclear. METHODS: Retrospective cohort study encompassing all patients in the Swedish national inpatient register, who underwent splenectomy in 1970-2009. Patients were followed for hospitalization for or death from sepsis, as identified using national inpatient and cause of death registers. Relative risks, comparing patients to the background population were expressed as standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs). RESULTS: Altogether, 20,132 splenectomized patients were included. The overall SIR for hospitalization for sepsis was 5.7 [95% confidence interval (CI), 5.6-6.0]. However, risks depended on the indication for splenectomy, with SIRs varying from 3.4 (95% CI, 3.0-3.8) for trauma patients to 18 (95% CI, 16-19) for patients with hematologic malignancies. SMRs ranged from 3.1 (95% CI, 2.1-4.3) for trauma to 8.7 (95% CI, 6.8-11) for hematologic disease. In regression analyses adjusting for age at splenectomy, follow-up time, sex, and calendar year of splenectomy, there were no significant risk decreases after implementation of routine vaccination, except for in patients with malignant and non-malignant hematologic disease. CONCLUSIONS: The risk of hospitalization or death from sepsis is high in patients who previously underwent splenectomy and depends on the indication for splenectomy. The effectiveness of current vaccination practices warrants further evaluation.

Saline versus Plasma-Lyte A in initial resuscitation of trauma patients: a randomized trial.

OBJECTIVE: We sought to compare resuscitation with 0.9% NaCl versus Plasma-Lyte A, a calcium-free balanced crystalloid solution, hypothesizing that Plasma-Lyte A would better correct the base deficit 24 hours after injury. BACKGROUND: Sodium chloride (0.9%) (0.9% NaCl), though often used for resuscitation of trauma patients, may exacerbate the metabolic acidosis that occurs with injury, and this acidosis may have detrimental clinical effects. METHODS: We conducted a randomized, double-blind, parallel-group trial (NCT01270854) of adult trauma patients requiring blood transfusion, intubation, or operation within 60 minutes of arrival at the University of California Davis Medical Center. Based on a computer-generated, blocked sequence, subjects received either 0.9% NaCl or Plasma-Lyte A for resuscitation during the first 24 hours after injury. The primary outcome was mean change in base excess from 0 to 24 hours. Secondary outcomes included 24-hour arterial pH, serum electrolytes, fluid balance, resource utilization, and in-hospital mortality. RESULTS: Of 46 evaluable subjects (among 65 randomized), 43% had penetrating injuries, injury severity score was 23 ± 16, 20% had admission systolic blood pressure less than 90 mm Hg, and 78% required an operation within 60 minutes of arrival. The baseline pH was 7.27 ± 0.11 and base excess -5.9 ± 5.0 mmol/L. The mean improvement in base excess from 0 to 24 hours was significantly greater with Plasma-Lyte A than with 0.9% NaCl {7.5 ± 4.7 vs 4.4 ± 3.9 mmol/L; difference: 3.1 [95% confidence interval (CI): 0.5-5.6]}. At 24 hours, arterial pH was greater [7.41 ± 0.06 vs 7.37 ± 0.07; difference: 0.05 (95% CI: 0.01-0.09)] and serum chloride was lower [104 ± 4 vs 111 ± 8 mEq/L; difference: -7 (95% CI: -10 to -3)] with Plasma-Lyte A than with 0.9% NaCl. Volumes of study fluid administered, 24-hour urine output, measures of resource utilization, and mortality did not significantly differ between the 2 arms. CONCLUSIONS: Compared with 0.9% NaCl, resuscitation of trauma patients with Plasma-Lyte A resulted in improved acid-base status and less hyperchloremia at 24 hours postinjury. Further studies are warranted to evaluate whether resuscitation with Plasma-Lyte A improves clinical outcomes.

Leukoreduction and ultraviolet treatment reduce both the magnitude and the duration of the HLA antibody response.

BACKGROUND: Both leukoreduction and ultraviolet (UV) light treatment of blood products have been shown to reduce the incidence of HLA antibody development in recipients, but the impact of these treatments on the magnitude and persistence of the antibody response is less clear. STUDY DESIGN AND METHODS: Longitudinal samples from 319 subjects taken from four different study cohorts were evaluated for HLA antibodies to determine the effects of leukoreduction and UV treatment on HLA antibody generation and persistence. RESULTS: Subjects receiving leukoreduced or UV-treated blood products were less likely to generate Class I HLA antibodies, and those receiving leukoreduced blood were also less likely to generate Class II HLA antibodies. Among those receiving nonleukoreduced blood, 55% developed Class I HLA antibodies and 51% developed Class II HLA antibodies compared with 28% (Class I) and 15% (Class II) for those receiving leukoreduced blood and 36% (Class I) and 54% (Class II) for those receiving UV-treated blood. Among alloimmunized subjects, leukoreduction resulted in a significant twofold reduction in the magnitude of Class I HLA antibodies, and UV treatment resulted in a significant threefold reduction in the magnitude of Class II HLA antibodies. Both treatments resulted in shorter persistence of Class I HLA antibodies. CONCLUSIONS: These data demonstrate that leukoreduction and UV treatment of blood products results not only in a reduction in the incidence of HLA antibody production, but also in lower and more transient HLA antibody levels among sensitized transfusion recipients.

Validity of the AHRQ patient safety indicator for postoperative physiologic and metabolic derangement based on a national sample of medical records.

OBJECTIVE: The Agency for Healthcare Research and Quality Patient Safety Indicator (PSI) 10, "Postoperative Physiologic and Metabolic Derangement" (PPMD), uses administrative data to detect postoperative acute kidney injury (AKI) requiring dialysis and diabetes-related complications. We sought to evaluate the indicator's criterion validity. RESEARCH DESIGN: We conducted a retrospective cross-sectional study of hospitalization records flagged positive and negative by PSI 10 from a diverse set of 35 hospitals between February 1, 2006 and June 30, 2009. Trained nurse abstractors reviewed medical records. We determined the indicator's sensitivity, specificity, and positive and negative predictive values. RESULTS: Of 94 records flagged by PSI 10 (87 for AKI, 7 for diabetic complications, 1 for both), 69 (73%) involved an accurately coded event; 60 (64%; 95% CI, 46%-79%) represented true PPMD from a clinical perspective. Two of 8 records flagged for diabetic complications were true events. Nineteen false positives involved preoperative renal failure. Three of 230 records flagged negative (enriched with questionably negative records) represented true PPMD. The indicator's sensitivity was 66% (20%-94%), specificity 99.9% (99.5%-100%), and negative predictive value 99.9% (99.4%-100%). Considering dialysis access procedures tantamount to dialysis and excluding records with lower urinary tract obstruction might increase the sensitivity and positive predictive value to 98% (87%-100%) and 72% (50%-87%), respectively. CONCLUSIONS: PSI 10 mostly concerns AKI and currently has moderate criterion validity, which might improve with increased use of "present on admission" coding, abandonment of the diabetes criteria, and adjustments to the indicator specifications regarding dialysis access and urinary tract obstruction.

A Least Absolute Shrinkage and Selection Operator-Derived Predictive Model for Postoperative Respiratory Failure in a Heterogeneous Adult Elective Surgery Patient Population.

BACKGROUND: Postoperative respiratory failure (PRF) is associated with increased hospital charges and worse patient outcomes. Reliable prediction models can help to guide postoperative planning to optimize care, to guide resource allocation, and to foster shared decision-making with patients. RESEARCH QUESTION: Can a predictive model be developed to accurately identify patients at high risk of PRF? STUDY DESIGN AND METHODS: In this single-site proof-of-concept study, we used structured query language to extract, transform, and load electronic health record data from 23,999 consecutive adult patients admitted for elective surgery (2014-2021). Our primary outcome was PRF, defined as mechanical ventilation after surgery of > 48 h. Predictors of interest included demographics, comorbidities, and intraoperative factors. We used logistic regression to build a predictive model and the least absolute shrinkage and selection operator procedure to select variables and to estimate model coefficients. We evaluated model performance using optimism-corrected area under the receiver operating curve and area under the precision-recall curve and calculated sensitivity, specificity, positive and negative predictive values, and Brier scores. RESULTS: Two hundred twenty-five patients (0.94%) demonstrated PRF. The 18-variable predictive model included: operations on the cardiovascular, nervous, digestive, urinary, or musculoskeletal system; surgical specialty orthopedic (nonspine); Medicare or Medicaid (as the primary payer); race unknown; American Society of Anesthesiologists class ≥ III; BMI of 30 to 34.9 kg/m2; anesthesia duration (per hour); net fluid at end of the operation (per liter); median intraoperative FIO2, end title CO2, heart rate, and tidal volume; and intraoperative vasopressor medications. The optimism-corrected area under the receiver operating curve was 0.835 (95% CI,0.808-0.862) and the area under the precision-recall curve was 0.156 (95% CI, 0.105-0.203). INTERPRETATION: This single-center proof-of-concept study demonstrated that a structured query language extract, transform, and load process, based on readily available patient and intraoperative variables, can be used to develop a prediction model for PRF. This PRF prediction model is scalable for multicenter research. Clinical applications include decision support to guide postoperative level of care admission and treatment decisions.

Variation in academic medical centers' coding practices for postoperative respiratory complications: implications for the AHRQ postoperative respiratory failure Patient Safety Indicator.

BACKGROUND: The Agency for Healthcare Research and Quality Patient Safety Indicator (PSI) 11 uses International Classification of Disease, 9th Clinical Modification diagnosis code 518.81 ("Acute respiratory failure")-but not the closely related alternative, 518.5 ("Pulmonary insufficiency after trauma and surgery")-to detect cases of postoperative respiratory failure. We sought to determine whether hospitals vary in the use of 518.81 versus 518.5 and whether such variation correlates with coder beliefs. STUDY DESIGN: We conducted a cross-sectional analysis of administrative data from July 2009 through June 2010 for UHC (formerly University HealthSystem Consortium)-affiliated centers to assess the use of diagnosis codes 518.81 and 518.5 in PSI 11-eligible cases. We also surveyed coders at these centers to evaluate whether variation in the use of 518.81 versus 518.5 might be linked to coder beliefs. We asked survey respondents which diagnosis they would use for 2 ambiguous cases of postoperative pulmonary complications and how much they agreed with 6 statements about the coding process. RESULTS: UHC-affiliated centers demonstrated wide variation in the use of 518.81 and 518.5, ranging from 0 to 26 cases and 0 to 56 cases/1000 PSI 11-eligible hospitalizations, respectively. Of 56 survey respondents, 64% chose 518.81 and 30% chose 518.5 for a clinical scenario involving postoperative respiratory failure, but these responses were not associated with actual coding of 518.81 or 518.5 at the center level. Sixty-two percent of respondents agreed that they are constrained by the words that physicians use. Their self-reported likelihood of querying physicians to clarify the diagnosis was significantly associated with coding of 518.5 at the center level. CONCLUSIONS: The extent to which diagnosis code 518.81 is used relative to 518.5 varies considerably across centers, based on local coding practice, the specific wording of physician documentation, and coder-physician communication. To standardize the coding of postoperative respiratory failure, the 518.81 and 518.5 codes have recently been revised to make the available options clearer and mutually exclusive, which may improve the capacity of PSI 11 to discriminate true differences in quality of care.

Distinct roles of trauma and transfusion in induction of immune modulation after injury.

BACKGROUND: Trauma and transfusion can both alter immunity, and while transfusions are common among traumatically injured patients, few studies have examined their combined effects on immunity. STUDY DESIGN AND METHODS: We tracked the plasma levels of 41 immunomodulatory proteins in 56 trauma patients from time of injury up to 1 year later. In addition, a murine model was developed to distinguish between the effects of transfusion and underlying injury and blood loss. RESULTS: Thirty-one of the proteins had a significant change over time after traumatic injury, with a mixed early response that was predominantly anti-inflammatory followed by a later increase in proteins involved in wound healing and homeostasis. Results from the murine model revealed similar cytokine responses to humans. In mice, trauma and hemorrhage caused early perturbations in a number of the pro- and anti-inflammatory mediators measured, and transfusion blunted early elevations in interleukin (IL)-6, IL-10, matrix metalloproteinase-9, and interferon-γ. Transfusion caused or exacerbated changes in monocyte chemotactic protein-1, IL-1α, IL-5, IL-15, and soluble E-selectin. Finally, trauma and hemorrhage alone increased CXCL1 and IL-13. CONCLUSIONS: This work provides a detailed characterization of the major shift in the immunologic environment in response to trauma and transfusion and clarifies which immune mediators are affected by trauma and hemorrhage and which by transfusion.

Using the Agency for Healthcare Research and Quality patient safety indicators for targeting nursing quality improvement.

Quantifying the critical impact nurses have on the prevention and early recognition of potential complications and adverse events, such as those identified by the Agency for Healthcare Research and Quality (AHRQ) patient safety indicators (PSI), is becoming increasingly important. In this paper, we describe how the AHRQ PSI may be used to identify nursing-specific opportunities to improve care based on data from the national AHRQ PSI validation pilot project.