Incidence and prognosis of abdominal complications after cardiopulmonary bypass.

The incidence of abdominal complications after cardiopulmonary bypass is low but associated with a high mortality. From January 1991 to October 1996, 4288 patients, of a mean age of 62.5 years, underwent open-heart surgery. Fifty-nine (1 of 4) of these patients developed early abdominal complications. These included 36% with a paralytic ileus, 21% with erosive gastritis, 18% with upper gastrointestinal haemorrhage, 12% with intestinal ischaemia, 5% with pseudo-obstruction of the colon, 6% with acute cholecystitis and 2% with acute pancreatitis. After coronary artery bypass grafting mean cardiopulmonary bypass time was 94.4 min. There were abdominal complications in 1.0% and one hospital death. After valve surgery and combined surgery the mean cardiopulmonary bypass time was 129 min. There were abdominal complications in 2.4% (alpha = 0.01) and seven deaths. Fourteen patients (24%) underwent abdominal operations: three had caecostomies for pseudo-obstruction of the colon, seven had a hemicolectomy, two had a cholecystectomy and two had resection of the ventricle. The hospital mortality rate was 13.5%. Abdominal complications were significantly more frequent after valve or combined operations of the coronaries and valves in comparison with isolated coronary artery bypass grafting. Cardiac operations with extended cardiovascular bypass time were more likely to produce abdominal complications.     

Functional connectivity and information flow of the respiratory neural network in chronic obstructive pulmonary disease

Breathing involves a complex interplay between the brainstem automatic network and cortical voluntary command. How these brain regions communicate at rest or during inspiratory loading is unknown. This issue is crucial for several reasons: (i) increased respiratory loading is a major feature of several respiratory diseases, (ii) failure of the voluntary motor and cortical sensory processing drives is among the mechanisms that precede acute respiratory failure, (iii) several cerebral structures involved in responding to inspiratory loading participate in the perception of dyspnea, a distressing symptom in many disease. We studied functional connectivity and Granger causality of the respiratory network in controls and patients with chronic obstructive pulmonary disease (COPD), at rest and during inspiratory loading. Compared with those of controls, the motor cortex area of patients exhibited decreased connectivity with their contralateral counterparts and no connectivity with the brainstem. In the patients, the information flow was reversed at rest with the source of the network shifted from the medulla towards the motor cortex. During inspiratory loading, the system was overwhelmed and the motor cortex became the sink of the network. This major finding may help to understand why some patients with COPD are prone to acute respiratory failure. Network connectivity and causality were related to lung function and illness severity. We validated our connectivity and causality results with a mathematical model of neural network. Our findings suggest a new therapeutic strategy involving the modulation of brain activity to increase motor cortex functional connectivity and improve respiratory muscles performance in patients. Hum Brain Mapp 37:2736–2754, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.     

Risk factors of early complications after thoracic and lumbar spinal deformity surgery: a systematic review and meta-analysis

European Spine Journal - To determine risk factors increasing susceptibility to early complications (intraoperative and postoperative within 6 weeks) associated with surgery to correct...     

High-calcium intake abolishes hyperoxaluria and reduces urinary crystallization during a 20-fold normal oxalate load in humans

Background: The aim of the study was to test whether increasing dietary calcium intake lowers intestinal oxalate absorption and thereby prevents hyperoxaluria and urinary crystallization during a 20-fold normal oxalate load in healthy subjects. Methods: Fourteen healthy male volunteers (age 23-44 years, BMI 21.5-27.7 kg/m²) collected 24-h urines while on free choice diet as well as on two standardized diets. The latter contained 2545 kcal, 2500 ml of mineral water, 102 g of protein, 13.6 g of sodium chloride and 2220 mg of oxalate ( 20-fold content of an average diet). Subjects were studied twice while on the standardized diet, once while eating a normal amount of calcium (1211 mg/day, oxalate-rich, diet), and once while eating 3858 mg of calcium /day (calcium and oxalate-rich diet). Results: Compared with the free-choice diet (322±36 &mgr;mol/d), UOx X V increased to 780±722 &mgr;mol/d on the oxalate-rich diet (P=0.001) and fell again to 326±31 &mgr;mol/d on calcium and oxalate-rich diet (P=0.001 vs oxalate-rich diet). Urinary glycolate (a metabolic precursor of Ox) always remained below the upper limit of the normal range and did not change between different diets, indicating that changes in UOx x V reflect respective variations in intestinal absorption of Ox. UCa x V was 4.60±0.45 mmol/d on the free choice diet and 3.20±0.32 mmol/d on the oxalate-rich diet (P=0.011 vs free-choice diet); it increased to 7.28±0.74 mmol/d on the calcium- and oxalate-rich diet (P=0.001 vs free-choice and oxalate-rich diets). As indicated by the AP (CaOx) index (Tiselius), urinary supersaturation did not vary significantly between the three diets. In freshly voided morning urines (studied in 8/14 subjects) on the oxalate-rich diet, CaOx crystals or crystal aggregates of up to 80 &mgr;m diameter were found in 5/8 urines, whereas this never occurred on the free-choice diet and only once on the calcium- and oxalate-rich diet. Conclusion: Increasing calcium intake while eating Ox-rich food prevents dietary hyperoxaluria and reduces CaOx crystallization in healthy subjects. This further illustrates that dietary counseling to idiopathic calcium-stone formers should ensure sufficient calcium intake, especially during oxalate-rich meals.     

Fractionated external beam radiotherapy of skull base metastases with cranial nerve involvement

Background and purpose

Skull base metastases frequently appear in a late stage of various tumor entities and cause pain and neurological disorders which strongly impair patient quality of life. This study retrospectively analyzed fractionated external beam radiotherapy (EBRT) as a palliative treatment approach with special respect to neurological outcome, feasibility and acute toxicity.

Patients and methods

A total of 30 patients with skull base metastases and cranial nerve disorders underwent EBRT with a mean total dose of 31.6 Gy. Neurological status was assessed before radiotherapy, during radiotherapy and 2 weeks afterwards categorizing orbital, parasellar, middle fossa, jugular foramen and occipital condyle involvement and associated clinical syndromes. Neurological outcome was scored as persistence of symptoms, partial response, good response and complete remission. Treatment-related toxicity and overall survival were assessed.

Results

Before EBRT 37 skull base involvement syndromes were determined with 4 patients showing more than 1 syndrome. Of the patients 81.1?% responded to radiotherapy with 10.8?% in complete remission, 48.6?% with good response and 21.6?% with partial response. Grade 1 toxicity of the skin occurred in two patients and grade 1 hematological toxicity in 1 patient under concurrent chemoradiotherapy. Median overall survival was 3.9 months with a median follow-up of 45 months.

Conclusion

The use of EBRT for skull base metastases with symptomatic involvement of cranial nerves is marked by good therapeutic success in terms of neurological outcome, high feasibility and low toxicity rates. These findings underline EBRT as the standard therapeutic approach in the palliative setting.     

Susceptibility-weighted MR imaging of radiation therapy-induced cerebral microbleeds in patients with glioma: a comparison between 3T and 7T

Introduction

Cerebral microbleeds have been observed in normal-appearing brain tissue of patients with glioma years after receiving radiation therapy. The contrast of these paramagnetic lesions varies with field strength due to differences in the effects of susceptibility. The purpose of this study was to compare 3T and 7T MRI as platforms for detecting cerebral microbleeds in patients treated with radiotherapy using susceptibility-weighted imaging (SWI).

Methods

SWI was performed with both 3T and 7T MR scanners on ten patients with glioma who had received prior radiotherapy. Imaging sequences were optimized to obtain data within a clinically acceptable scan time. Both T2*-weighted magnitude images and SWI data were reconstructed, minimum intensity projection was implemented, and microbleeds were manually identified. The number of microbleeds was counted and compared among datasets.

Results

Significantly more microbleeds were identified on SWI than magnitude images at both 7T (p?=?0.002) and 3T (p?=?0.023). Seven-tesla SWI detected significantly more microbleeds than 3T SWI for seven out of ten patients who had tumors located remote from deep brain regions (p?=?0.016), but when the additional three patients with more inferior tumors were included, the difference was not significant.

Conclusion

SWI is more sensitive for detecting microbleeds than magnitude images at both 3T and 7T. For areas without heightened susceptibility artifacts, 7T SWI is more sensitive to detecting radiation therapy-induced microbleeds than 3T SWI. Tumor location should be considered in conjunction with field strength when selecting the most appropriate strategy for imaging microbleeds.     

Need for closure of secundum atrial septal defect in infancy

OBJECTIVES: Closure of isolated secundum atrial septal defect is generally recommended at the age of 4 to 5 years. However, there are children with isolated secundum atrial septal defect in whom early closure should be performed. We aimed to assess the underlying conditions that led to earlier closure in this special patient group and to analyze the outcome. METHODS AND RESULTS: From January 1990 through August 2002, 24 infants with isolated secundum atrial septal defect underwent surgical closure within the first year of life. All children were symptomatic. Signs of pulmonary hyperperfusion, such as tachydyspnea, failure to thrive, recurrent respiratory infections, or heart failure, were present. Four infants required artificial ventilation. Ten patients had additional problems, such as prematurity with chronic lung disease, hepato-omphalocele and congenital diaphragmatic hernia, which were present in 1 patient each. Eleven patients had defined dysmorphic syndromes. All but 1 infant underwent preoperative invasive hemodynamic evaluation. Thirteen patients had pulmonary hypertension preoperatively. The follow-up time was 46 +/- 33 months (range, 4-125 months). At follow-up, pulmonary artery pressure proved to be normal in 11 of the 13 children who had pulmonary hypertension previously. One patient died of persistent pulmonary hypertension. Clinical performance, growth, and development improved in nearly all patients. All ventilator-dependent children could be weaned shortly after atrial septal defect closure. CONCLUSIONS: If lungs are compromised, even a minor left-to-right shunt might be poorly tolerated in infancy. In these children early surgical closure of an isolated secundum atrial septal defect should be performed to support thrive and growth and to prevent the onset of irreversible changes of the pulmonary vasculature.