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71.

Introduction

This investigation aimed to evaluate thrombotic risk factors in children, with special reference to autoantibodies against prothrombin and protein S.

Materials and methods

We studied 57 consecutive Swedish children and adolescents referred with a radiologically confirmed acute thrombotic event. Clinical data were collected and a thrombophilia investigation was performed, including analysis of autoantibodies against protein S (anti-PS) and prothrombin (anti-PT). The anti-PS and anti-PT autoantibodies were also investigated in sera from 47 healthy controls. Detection of autoantibodies was performed by quantitative enzyme-linked immunosorbent assays.

Results

Results for anti-PT antibodies were positive in 21% (12/57) of the patients and 2.1% (1/47) of the controls (OR 12.0, 95% CI 1.7-534; = 0.005). Seven percent (4/57) of the patients and 2.1% (1/47) of the controls were positive for anti-PS antibodies (OR 3.4, 95% CI 0.3-174; > 0.30). The FV G1691A mutation was found in 25% (14/57), and 44% (25/57) had 2 or more prothrombotic risk factors. Sixty percent (34/57) of the thrombosis patients were female. Peaks in frequency of thromboembolic events were found in the neonatal and the adolescent periods. Fifty-three percent (30/57) had thrombosis in the lower venous system. Associated clinical conditions occurred in 91% (52/57): systemic illness in 31% (18/57), infections in 26% (15/57), and oral contraceptive use in 25% (14/57). Four percent (2/57) had no apparent clinical or prothrombotic risk factors.

Conclusions

This study suggests that anti-PT autoantibodies may be common risk factors for thrombosis in children, and it confirms the multifactorial nature of pediatric thrombosis.  相似文献   
72.
To map in vivo cortical circuitry at the mesoscale, we applied a novel approach to map interareal functional connectivity. Electrical intracortical microstimulation (ICMS) in conjunction with optical imaging of intrinsic signals (OIS) was used map functional connections in somatosensory cortical areas in anesthetized squirrel monkeys. ICMS produced activations that were focal and that displayed responses which were stimulation intensity dependent. ICMS in supragranular layers of Brodmann Areas 3b, 1, 2, 3a, and M1 evoked interareal activation patterns that were topographically appropriate and appeared consistent with known anatomical connectivity. Specifically, ICMS revealed Area 3b connections with Area 1; Area 1 connections with Areas 2 and 3a; Area 2 connections with Areas 1, 3a, and M1; Area 3a connections with Areas M1, 1, and 2; and M1 connections with Areas 3a, 1, and 2. These somatosensory connectivity patterns were reminiscent of feedforward patterns observed anatomically, although feedback contributions are also likely present. Further consistent with anatomical connectivity, intra-areal and intra-areal patterns of activation were patchy with patch sizes of 200–300 μm. In summary, ICMS with OIS is a novel approach for mapping interareal and intra-areal connections in vivo. Comparisons with feedforward and feedback anatomical connectivity are discussed.  相似文献   
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76.

Background

Children with congenital heart disease (CHD) often require noncardiac surgery. We compared outcomes following open and laparoscopic intraabdominal surgery among children with and without CHD.

Methods

We performed a retrospective cohort study using the 2013–2015 National Surgical Quality Improvement Project-Pediatrics. We matched 45,012 children < 18 years old who underwent laparoscopic surgery to 45,012 children who underwent open surgery. We determined the associations between laparoscopic (versus open) surgery and 30-day mortality, in-hospital mortality, 30-day morbidity, and postoperative length-of-stay.

Results

Among children with minor CHD, laparoscopic surgery was associated with lower 30-day mortality (Odds Ratio [OR] 0.34 [95% Confidence Interval 0.15–0.79]), inhospital mortality (OR 0.42 [0.22–0.81]) and 30-day morbidity (OR 0.61 [0.50–0.73]). As CHD severity increased, this benefit of laparoscopic surgery decreased for 30-day morbidity (ptrend = 0.01) and in-hospital mortality (ptrend = 0.05), but not for 30-day mortality (ptrend = 0.27). Length-of-stay was shorter for laparoscopic approaches for children at cost of higher readmissions. On subgroup analysis, laparoscopy was associated with lower odds of postoperative blood transfusion in all children.

Conclusions

Intraabdominal laparoscopic surgery compared to open surgery is associated with decreased morbidity in patients with no CHD and lower morbidity and mortality in patients with minor CHD, but not in those with more severe CHD.

Level-of-evidence

Level III: Treatment Study.  相似文献   
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78.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
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80.

Objective

The preferred arterial cannulation site for elective proximal aortic procedures requiring circulatory arrest varies, and different sites have been tried. We evaluated the relationships between arterial cannulation site and adverse outcomes, including stroke, in patients undergoing elective aortic arch surgery.

Methods

We reviewed the records of 938 patients who underwent elective hemiarch or total arch surgery with circulatory arrest between 2006 and 2016. Five cannulation sites were used: the right axillary (n = 515; 54.9%), innominate (n = 376; 40.1%), and right common carotid arteries (n = 15; 1.6%), each with a side graft; the ascending aorta (n = 19; 2.0%); and the femoral artery (n = 13; 1.4%). Multivariable logistic regression analysis was used to model the effects of cannulation site on adverse outcomes for the entire cohort and for a subcohort of 891 patients who underwent innominate or axillary artery cannulation. Propensity-matching yielded 564 patients (282 pairs) from the right axillary and innominate artery groups.

Results

For the entire cohort, mortality, stroke, and composite adverse outcome (operative death or persistent stroke or renal failure at hospital discharge) rates were 7.0%, 4.1%, and 9.8%. In the multivariable analysis of the axillary/innominate subcohort, cannulation site did not independently predict operative mortality, persistent stroke, or composite adverse event. These results were confirmed with the propensity-matched analysis, where both axillary and innominate artery cannulation provided equivalent composite adverse event rates, operative death rates, and overall stroke rates.

Conclusions

During elective arch surgery, right axillary artery cannulation and innominate artery cannulation (both via a side graft) produce excellent results and can be used interchangeably.  相似文献   
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