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31.
Background: Morbidly obese patients, during anesthesia and paralysis, experience more severe impairment of respiratory mechanics and gas exchange than normal subjects. The authors hypothesized that positive end-expiratory pressure (PEEP) induces different responses in normal subjects (n = 9; body mass index < 25 kg/m2) versus obese patients (n = 9; body mass index > 40 kg/m2).

Methods: The authors measured lung volumes (helium technique), the elastances of the respiratory system, lung, and chest wall, the pressure-volume curves (occlusion technique and esophageal balloon), and the intraabdominal pressure (intrabladder catheter) at PEEP 0 and 10 cm H2O in paralyzed, anesthetized postoperative patients in the intensive care unit or operating room after abdominal surgery.

Results: At PEEP 0 cm H2O, obese patients had lower lung volume (0.59 +/- 0.17 vs. 2.15 +/- 0.58 l [mean +/- SD], P < 0.01); higher elastances of the respiratory system (26.8 +/- 4.2 vs. 16.4 +/- 3.6 cm H2O/l, P < 0.01), lung (17.4 +/- 4.5 vs. 10.3 +/- 3.2 cm H2O/l, P < 0.01), and chest wall (9.4 +/- 3.0 vs. 6.1 +/- 1.4 cm H2O/l, P < 0.01); and higher intraabdominal pressure (18.8 +/- 7.8 vs. 9.0 +/- 2.4 cm H2O, P < 0.01) than normal subjects. The arterial oxygen tension was significantly lower (110 +/- 30 vs. 218 +/- 47 mmHg, P < 0.01; inspired oxygen fraction = 50%), and the arterial carbon dioxide tension significantly higher (37.8 +/- 6.8 vs. 28.4 +/- 3.1, P < 0.01) in obese patients compared with normal subjects. Increasing PEEP to 10 cm H2O significantly reduced elastances of the respiratory system, lung, and chest wall in obese patients but not in normal subjects. The pressure-volume curves were shifted upward and to the left in obese patients but were unchanged in normal subjects. The oxygenation increased with PEEP in obese patients (from 110 +/- 30 to 130 +/- 28 mmHg, P < 0.01) but was unchanged in normal subjects. The oxygenation changes were significantly correlated with alveolar recruitment (r = 0.81, P < 0.01).  相似文献   

32.
Abstract Amyotrophic lateral sclerosis (ALS) is the most common form of motor neuron disease. We describe the case of a patient with a rapidly progressive form of ALS characterized by both upper and lower motor neuron impairment, no early bulbar signs and severe pain in all four extremities. The patient had a heterozygous c.271G > A mutation in SOD1, leading to an amino acids substitution of asparagine to aspartate at position 90 of the protein chain (p.D90N). Our report confirms that ALS patients with D90 codon heterozygous mutations may be associated with rapid progression and a prominent pain syndrome.  相似文献   
33.
Atrial fibrillation (AF) is a common arrhythmia among patients scheduled for open heart surgery and is associated with increased morbidity and mortality. According to international guidelines, symptomatic and selected asymptomatic patients should be offered concomitant surgical AF ablation in conjunction with valvular or coronary surgery. The gold standard in AF surgery is the Cox Maze III ("cut-and-sew") procedure, with surgical incisions in both atria according to a specified pattern, in order to prevent AF reentry circuits from developing. Over 90% of patients treated with the Cox Maze III procedure are free of AF after 1 year. Recent developments in ablation technology have introduced several energy sources capable of creating nonconducting atrial wall lesions. In addition, simplified lesion patterns have been suggested, but results with these techniques have been unsatisfactory. There is a clear need for standardization in AF surgery. The Swedish Arrhythmia Surgery Group, represented by surgeons from all Swedish units for cardiothoracic surgery, has therefore reached a consensus on surgical treatment of concomitant AF. This consensus emphasizes adherence to the lesion pattern in the Cox Maze III procedure and the use of biatrial lesions in nonparoxysmal AF.  相似文献   
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One hundred sixteen patients who underwent surgery for early gastric cancer (EGC) at Careggi General Hospital in Florence between 1987 and 1992 were studied with regard to clinicopathologic features, incidence, and recurrence of the disease. The overall 5-year cumulative survival rate was 87.5%, and the disease-specific 5-year survival rate was 88.2%. EGC was limited to the mucosa in 43 patients (37%), while it infiltrated the submucosa in 73 others (63%). At the time of surgery, 9.5% of patients were found to have lymph node metastasis, always concomitant with submucosal invasion. There was 1 postoperative death (0.8%); 16 patients (13.7%) died of tumor recurrence, and 20 (17.2%) died of unrelated causes. Analysis of recurrence showed an intestinal histotype in 13 patients (81.2%), submucosal infiltration in 14 patients (87.5%), a Pen-A growth pattern in 8 patients (50%), and lymph node involvement in 3 patients (18.7%). The Cox proportional hazard model indicated that age and depth of wall invasion were statistically significant. The best predictor of survival appears to be the depth of invasion within the gastric wall. The claim by several investigators that prognosis for EGC is also associated with the presence of lymph node involvement is not supported by the present study. The postoperative 5-year survival rate in node-negative patients was 88.8% compared to 81.8% in node-positive patients (p = 0.296).  相似文献   
37.
Renal replacement therapy in lupus nephritis   总被引:6,自引:0,他引:6  
The indications and the choice of renal replacement therapy for lupus patients are similar to those for other uremic patients. However, lupus patients can pose some particular problems. First, 10-28% of patients needing dialysis can have a partial renal function recovery. Therefore, the clinician has to decide whether to administer a rescue treatment, risking side-effects, or to reduce immunosuppression precluding a potential recovery. Many patients on regular dialysis show subdued biological and clinical activity. Others can show a hectic disease activity, particularly in the 1st year. In these cases, treatment is difficult, as vigorous immunosuppression can expose uremic patients to severe side-effects. The presence of circulating antiphospholipid antibodies (aPL) can favor thrombosis or stenosis of vascular access (VA). Renal transplantation is the best therapy for most lupus patients with end-stage renal failure. Many, but not all, studies have reported similar patient and graft survival rates in lupus and in non-lupus transplant recipients. The results are much better with living donor transplantation. Patients with aPL, black patients and those on long-term dialysis have a higher graft failure risk. Candidates with active lupus and/or those with significant iatrogenic morbidity should be advised to wait 6-12 months before transplantation. The recurrence risk of lupus nephritis ranged between 2% and 30% in different studies. The histological picture does not usually show severe features. Antiplatelet agents or anticoagulation can be advised for aPL patients.  相似文献   
38.
Objective To evaluate the prognostic significance of different clinico-pathological and molecular factors, and to compare survival after standard and extended pancreaticoduodenectomy (PD) in ampulla of Vater adenocarcinoma (AVAC). Summary Background Data There are discordant data on factors affecting prognosis, and hence therapeutic choices, in AVAC. Patients and Methods Clinical-pathological factors were evaluated in 59 patients, subjected to PD for AVAC; in 42 subjects information on chromosome 17p and 18q allelic losses (LOH) and microsatellite instability (MSI) was also available. The association between survival and type of PD was investigated in the 25 patients operated between 1990 and 2001 (16 standard and nine extended). Results The overall 5- and 10-year tumor-related survival rates were 46% and 33%, respectively. Sixteen patients had T-stages 1–2, 14 T-stage 3, and 29 T-stage 4 cancers. Chromosome 17p and 18q LOH were detected in 23 (55%) and 15 cases (36%), respectively, and in 12 cases (29%) coexisted. Five cases were MSI-positive (12%). At univariate analysis, poor survival was associated with cancer ulceration (P = 0.051), poor differentiation (P = 0.008), T-stage 4 (P < 0.001), nodal metastases (P = 0.004), chromosome 17p (P < 0.001) and 18q LOH (P = 0.002), and absence of MSI (P = 0.009). At multivariate analysis, only T-stage (P = 0.002) and 17p LOH (P = 0.001) were independent predictors of survival. All patients with MSI-positive cancers were long-survivors (>12 yrs), whereas only 30% of MSI-negative cancer patients survived at 5 years. Extended pancreaticoduodenectomy was associated with a 3-year disease-related survival higher than standard resection (83% vs 31%; P = 0.018). Conclusion MSI and chromosome 17p status allow to better define prognosis within ampullary cancers at the same stage. Surgery alone resulted curative in MSI-positive cancer patients, whereas it was inadequate in patients showing allelic losses, who might benefit from adjuvant therapy. In this observational study, extended PD was associated with increased survival compared to standard procedures. Presented at the 2006 Annual Meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, March 9–12, 2006  相似文献   
39.
Purpose For many years, the status of the axillary lymph nodes has been determined by an axillary lymphadenectomy. However, a sentinel lymph node biopsy has been shown to effectively replace the need for an axillary lymphadenectomy in order to determine the axillary staging. This study presents the preliminary results regarding the efficacy of fine-needle aspiration cytology (FNAC) to identify metastatic axillary lymph nodes in the pre-operative phase. Methods One hundred lymph nodes from 100 patients with histologically and cytologically confirmed breast cancer (cT1–2 cN0) underwent echo-guided FNAC. The diagnostic accuracy (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV]) for the axillary metastases was evaluated based on the histological findings of either a sentinel lymph node biopsy or an axillary lymphadenectomy as a reference standard. Results It was possible to avoid a sentinel lymph node biopsy in 30% of the cases; the sensitivity was 68%, specificity 100%, PPV 100%, and NPV 65%. Echo-guided FNAC of the axillary lymph nodes should thus be included among the regular diagnostic procedures of presurgical staging. Conclusion This simple, inexpensive, and minimally invasive technique makes it possible to avoid the additional cost of a sentinel lymph node biopsy while also sparing the patient the stress of undergoing a second surgery.  相似文献   
40.
Objective: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. Methods: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable ‘surgery of the thoracic aorta’. All survivors were followed-up for 1–41 months (16 ± 12). Results: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p < 0.05) and 10.3% (p = 0.67) obtained by the EuroSCORE full model and without ‘aortic surgery’, respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24 h. Conclusion: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates.  相似文献   
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