Impact of sepsis on risk of postoperative arterial and venous thromboses: large prospective cohort study

OBJECTIVES To evaluate the impact of preoperative sepsis on risk of postoperative arterial and venous thromboses. DESIGN Prospective cohort study using the National Surgical Quality Improvement Program database of the American College of Surgeons (ACS-NSQIP). SETTING Inpatient and outpatient procedures in 374 hospitals of all types across the United States, 2005-12. PARTICIPANTS 2,305,380 adults who underwent surgical procedures. MAIN OUTCOME MEASURES Arterial thrombosis (myocardial infarction or stroke) and venous thrombosis (deep venous thrombosis or pulmonary embolism) in the 30 days after surgery. RESULTS Among all surgical procedures, patients with preoperative systemic inflammatory response syndrome or any sepsis had three times the odds of having an arterial or venous postoperative thrombosis (odds ratio 3.1, 95% confidence interval 3.0 to 3.1). The adjusted odds ratios were 2.7 (2.5 to 2.8) for arterial thrombosis and 3.3 (3.2 to 3.4) for venous thrombosis. The adjusted odds ratios for thrombosis were 2.5 (2.4 to 2.6) in patients with systemic inflammatory response syndrome, 3.3 (3.1 to 3.4) in patients with sepsis, and 5.7 (5.4 to 6.1) in patients with severe sepsis, compared with patients without any systemic inflammation. In patients with preoperative sepsis, both emergency and elective surgical procedures had a twofold increased odds of thrombosis. CONCLUSIONS Preoperative sepsis represents an important independent risk factor for both arterial and venous thromboses. The risk of thrombosis increases with the severity of the inflammatory response and is higher in both emergent and elective surgical procedures. Suspicion of thrombosis should be higher in patients with sepsis who undergo surgery.

Effects of regional versus general anesthesia on outcomes after total hip arthroplasty: a retrospective propensity-matched cohort study

BACKGROUND Many orthopaedic surgical procedures can be performed with either regional or general anesthesia. We hypothesized that total hip arthroplasty with regional anesthesia is associated with less postoperative morbidity and mortality than total hip arthroplasty with general anesthesia. METHODS This retrospective propensity-matched cohort study utilizing the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database included patients who had undergone total hip arthroplasty from 2007 through 2011. After matching, logistic regression was used to determine the association between the type of anesthesia and deep surgical site infections, hospital length of stay, thirty-day mortality, and cardiovascular and pulmonary complications. RESULTS Of 12,929 surgical procedures, 5103 (39.5%) were performed with regional anesthesia. The adjusted odds for deep surgical site infections were significantly lower in the regional anesthesia group than in the general anesthesia group (odds ratio [OR] = 0.38; 95% confidence interval [CI] = 0.20 to 0.72; p < 0.01). The hospital length of stay (geometric mean) was decreased by 5% (95% CI = 3% to 7%; p < 0.001) with regional anesthesia, which translates to 0.17 day for each total hip arthroplasty. Regional anesthesia was also associated with a 27% decrease in the odds of prolonged hospitalization (OR = 0.73; 95% CI = 0.68 to 0.89; p < 0.001). The mortality rate was not significantly lower with regional anesthesia (OR = 0.78; 95% CI = 0.43 to 1.42; p > 0.05). The adjusted odds for cardiovascular complications (OR = 0.61; 95% CI = 0.44 to 0.85) and respiratory complications (OR = 0.51; 95% CI = 0.33 to 0.81) were all lower in the regional anesthesia group. CONCLUSIONS Compared with general anesthesia, regional anesthesia for total hip arthroplasty was associated with a reduction in deep surgical site infection rates, hospital length of stay, and rates of postoperative cardiovascular and pulmonary complications. These findings could have an important medical and economic impact on health-care practice.

The association between mental health and cigarette smoking in active duty military members

Previous research has shown an association between mental health status and cigarette smoking. This study examined four specific mental health predictors and the outcome variable any smoking, defined as smoking one or more cigarettes in the past 30 days. The population included active duty military members serving in the United States Army, Air Force, Navy and Marine Corps. The data was collected during the 2005 Department of Defense Survey of Health Related Behaviors Among Active Duty Military Personnel, a component of the Defense Lifestyle Assessment Program. The sample size included 13,603 subjects. This cross sectional prevalence study consisted of descriptive statistics, univariate analysis, and multivariate logistic regression analysis of the four mental health predictors and the any smoking outcome variable. Multivariate adjustment showed an association between the four mental health predictors and any smoking. This association is consistent with previous literature and can help guide public health officials in the development of smoking prevention and cessation programs.^

Risk factors for surgical site infections among patients undergoing major colon surgery in the United States 2007-2009

Background: Surgical site infections (SSIs) after abdominal surgeries account for approximately 26% of all reported SSIs. The Center for Disease Control and Prevention (CDC) defines 3 types of SSIs: superficial incisional, deep incisional, and organ/space. Preventing SSIs has become a national focus. This dissertation assesses several associations with the individual types of SSI in patients that have undergone colon surgery. ^ Methods: Data for this dissertation was obtained from the American College of Surgeons' National Surgical Quality Improvement Program (NSQIP); major colon surgeries were identified in the database that occurred between the time period of 2007 and 2009. NSQIP data includes more than 50 preoperative and 30 intraoperative factors; 40 collected postoperative occurrences are based on a follow-up period of 30 days from surgery. Initially, four individual logistic regressions were modeled to compare the associations between risk factors and each of the SSI groups: superficial, deep, organ/space and a composite of any single SSI. A second analysis used polytomous regression to assess simultaneously the associations between risk factors and the different types of SSIs, as well as, formally test the different effect estimates of 13 common risk factors for SSIs. The final analysis explored the association between venous thromboembolism (VTEs) and the different types of SSIs and risk factors. ^ Results: A total of 59,365 colon surgeries were included in the study. Overall, 13% of colon cases developed a single type of SSI; 8% of these were superficial SSIs, 1.4% was deep SSIs, and 3.8% were organ/space SSIs. The first article identifies the unique set of risk factors associated with each of the 4 SSI models. Distinct risk factors for superficial SSIs included factors, such as alcohol, chronic obstructive pulmonary disease, dyspnea and diabetes. Organ/space SSIs were uniquely associated with disseminated cancer, preoperative dialysis, preoperative radiation treatment, bleeding disorder and prior surgery. Risk factors that were significant in all models had different effect estimates. The second article assesses 13 common SSI risk factors simultaneously across the 3 different types of SSIs using polytomous regression. Then each risk factor was formally tested for the effect heterogeneity exhibited. If the test was significant the final model would allow for the effect estimations for that risk factor to vary across each type of SSI; if the test was not significant, the effect estimate would remain constant across the types of SSIs using the aggregate SSI value. The third article explored the relationship of venous thromboembolism (VTE) and the individual types of SSIs and risk factors. The overall incidence of VTEs after the 59,365 colon cases was 2.4%. All 3 types of SSIs and several risk factors were independently associated with the development of VTEs. ^ Conclusions: Risk factors associated with each type of SSI were different in patients that have undergone colon surgery. Each model had a unique cluster of risk factors. Several risk factors, including increased BMI, duration of surgery, wound class, and laparoscopic approach, were significant across all 4 models but no statistical inferences can be made about their different effect estimates. These results suggest that aggregating SSIs may misattribute and hide true associations with risk factors. Using polytomous regression to assess multiple risk factors with the multiple types of SSI, this study was able to identify several risk factors that had significant effect heterogeneity across the 3 types of SSI challenging the use of aggregate SSI outcomes. The third article recognizes the strong association between VTEs and the 3 types of SSIs. Clinicians understand the difference between superficial, deep and organ/space SSIs. Our results indicate that they should be considered individually in future studies.^

Silicoflagellates and ebridians from the New Jersey Transect DSDP Leg 93

Well-preserved and diverse silicoflagellate and ebridian populations are found in the lower and middle Eocene sediments of DSDP Site 605 and the upper Miocene sediments of DSDP Site 604. The ebridians outnumber the silicoflagellates in the siliceous interval of Site 605, but are less numerous at Site 604. The abundances of the various taxa are tabulated.

Cenozoic radiolaria in the western North Atlantic

Eight Cenozoic radiolarian zones were recognized in samples from two holes at Site 603, drilled on the lower continental rise off North America during Leg 93 of the Deep Sea Drilling Project. Paleocene to early Eocene radiolarian zones (Bekoma bidartensis, Buryella clinata, and Phormocyrtis striata striata zones) and early to late Miocene radiolarian zones (Calocycletta costata, Dorcadospyris alata, Diartus petterssoni, and Didymocyrtis antepenultima zones) were recognized in sediments from Holes 603 and 603B. In addition, a new Paleocene Bekoma campechensis radiolarian Zone is defined by the interval between the first morphotypic appearance of B. campechensis and the B. campechensis-B. bidartensis evolutionary transition. This zone is immediately below the B. bidartensis Zone of Foreman (1973), and has previously been discussed as a Paleocene "unnamed zone" by other investigators. A hiatus between Neogene and Paleogene sequences was also recognized in the radiolarian faunas.

Neogene and Paleocene-Maestrichtian calcareous nannofossils in sediments of the upper continental rise off New Jersey

Maestrichtian to Holocene calcareous nannofossils from two closely spaced sites on the upper continental rise some 100 miles (161 km) southeast of Atlantic City, New Jersey, were zoned in order to help date a major canyon-cutting event in the late Miocene and to delineate and correlate other hiatuses with seismic stratigraphy. Mid-middle Eocene through middle Miocene sediments (Zones CP14 to CN6) were not recovered in these holes, but nearly all other zones are accounted for. The Eocene section is described in a companion chapter (Applegate and Wise, 1987, doi:10.2973/dsdp.proc.93.118.1987). Nannofossils are generally sparse and moderately preserved in the clastic sediments of Site 604. Sedimentation rates are extremely high for the upper Pleistocene (201 m/m.y. minimum) above a hiatus calculated to span 0.44 to 1.1 Ma. The associated disconformity is correlated with local seismic reflection Horizon Pr . Sedimentation rates continue to be high (93 m/m.y.) down to a second hiatus in the upper Pliocene dated from about 2.4 to 2.9 (or possibly 3.3) Ma. The disconformity associated with this hiatus is correlated with local seismic reflection Horizon P2 and regional Reflector Blue, which can be interpreted to mark either the onset of Northern Hemisphere continental glaciation or circulation changes associated with the closure of the Central American Seaway. Sedimentation rates in the pre-glacial lower Pliocene are only about a third those in the glacial upper Pliocene. A prominent disconformity in the upper Miocene marks a major lithologic boundary that separates Messinian(?) glauconitic claystones above from lower Tortonian conglomeratic debris flows and turbidites below. The debris flows recovered are assigned to nannofossil Zones CN8a and CN7, but drilling difficulties prevented penetration of the bottom of this sequence some 100 m below the terminal depth of the hole. Correlation of the lower bounding seismic reflector (M2/Merlin?) to a drift sequence drilled on the lower rise at DSDP Site 603, however, predicts that the debris flows began close to the beginning of the late Miocene (upper Zone CN6 time) at about 10.5 Ma. The debris flows represent a major canyon-cutting event that we correlate with the beginning of the particularly severe late Miocene glaciations believed to be associated with the formation of the West Antarctic Ice Sheet. The existence of these spectacular debris flows strongly suggest that the late Miocene glacio-eustatic low stand occurred during Vail Cycle TM3.1 (lower Tortonian) rather than during Vail Cycle TM3.2 (Messinian) as originally published. Beneath a set of coalesced regional disconformities centered upon seismic reflection Horizon Au, coccoliths are abundant and in general are moderately preserved at Site 605 in a 619-m carbonate section extending from the middle Eocene Zone CP13b to the upper Maestrichtian Lithraphidites quadratus Zone. Sedimentation rates are 37 m/m.y. in the Eocene down to a condensed interval near the base (Zone CP9). A disconformity is suspected near the Eocene/Paleocene boundary. Sedimentation rates for the upper Paleocene Zone CP8 are similar to those of the Eocene, but Zones CP7 and CP6 lie within another condensed interval. The highest Paleocene rates are 67 m/m.y. down through Zones CP5 and CP4 to a major disconformity that separates the upper Paleocene from the Danian. This hiatus spans about 2.6 m.y. (upper Zone CP3 to lower Zone CP2) and corresponds to the major sea-level drop at the base of Vail Cycle TE2.1. As the most prominent break in this Paleogene section, it may correspond to seismic reflection Horizon A* of the North American Basin. Sedimentation rates from this point to the Cretaceous/Tertiary boundary drop to 11 m/m.y., still high for a Paleocene DSDP section. No major break in deposition could be detected at the Cretaceous/Tertiary boundary.

Ice and snow characteristics in Prydz Bay in 2006

Under the Chinese National Antarctic Research Expedition program in 2006, the annual thermal mass balance of landfast ice in the vicinity of Zhongshan Station, Prydz Bay, east Antarctica, was investigated. Sea ice formed from mid-February onward, and maximum ice thickness occurred in late November. Snow cover remained thin, and blowing snow caused frequent redistribution of the snow. The vertical ice salinity showed a 'question-mark-shaped' profile for most of the ice growth season, which only turned into an 'I-shaped' profile after the onset of ice melt. The oceanic heat flux as estimated from a flux balance at ice-ocean interface using internal ice temperatures decreased from 11.8 (±3.5) W/m**2 in April to an annual minimum of 1.9 (±2.4) W/m**2 in September. It remained low through late November, in mid-December it increased sharply to about 20.0 W/m**2. Simulations applying the modified versions of Stefan's law, taking account the oceanic heat flux and ice-atmosphere coupling, compare well with observed ice growth. There was no obvious seasonal cycle for the thermal conductivity of snow cover, which was also derived from internal ice temperatures. Its annual mean was 0.20 (±0.04) W/m/°C.