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61.
62.
Ninh T. Nguyen Kevin M. Reavis Marcelo W. Hinojosa Brian R. Smith Samuel E. Wilson 《Journal of gastrointestinal surgery》2009,13(6):1125-1128
Introduction We present a novel surgical technique for cholecystectomy utilizing three laparoscopic ports placed through the umbilicus.
This new method is natural orifice transumbilical surgery (NOTUS) and describes a laparoscopic operation that can be performed
with all incisions placed within the umbilicus obviating visible abdominal scars.
Objectives To develop a novel laparoscopic surgical technique for cholecystectomy utilizing only transumbilical incisions.
Summary Background Data Natural orifice translumenal endoscopic surgery (NOTES) has become an exciting area of surgical development. Significant limitations
to this surgical concept, however, are lack of surgical expertise and appropriate flexible instrumentation. An alternative
and competing technology to NOTES is NOTUS.
Methods We describe a patient in whom a laparoscopic surgical technique for cholecystectomy utilized incisions all placed entirely
within the umbilicus. This new technique is called NOTUS and describes a laparoscopic operation that can be performed without
visible abdominal scar.
Results The operative time was 70 min. There were no intraoperative complications. The patient did well postoperatively and was discharged
on the same operative day. There were no postoperative complications at 2 months follow-up.
Conclusion Cholecystectomy performed through laparoscopic incisions placed within the umbilicus was technically feasible and safe in
our patient. Development of advanced flexible instrumentation and visualization platforms may facilitate this new operative
approach. Further advantages of NOTUS cholecystectomy compared to conventional laparoscopic cholecystectomy will ultimately
require a randomized clinical trial. 相似文献
63.
Ana Flávia Marçal Pessoa PhD Juliana Costa Florim MSc Hosana Gomes Rodrigues PhD Vinicius Andrade‐Oliveira PhD Simone A. Teixeira PhD Kaio Fernando Vitzel PhD Rui Curi PhD Niels Olsen Saraiva Câmara PhD Marcelo N. Muscará PhD Marcelo Lazzaron Lamers PhD Marinilce Fagundes Santos PhD 《Wound repair and regeneration》2016,24(6):981-993
Oxidative stress aggravates several long‐term complications in diabetes mellitus. We evaluated the effectiveness of the oral administration of antioxidants (vitamins E and C, 40 and 100 mg/kg b.w., respectively) on skin wound healing acceleration in alloxan‐induced diabetic mice. Mice were wounded 30 days after the induction of diabetes. Antioxidants were effective in preventing oxidative stress, as assessed by TBARS. The enzymes catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase were increased in diabetics on the 3rd day post‐wounding; catalase and glutathione peroxidase remained still augmented in diabetics after 14th day postwounding, and the treatment with vitamins restored their activities to control. After 3 days, diabetic mice showed lower infiltration of inflammatory cells (including CD11b+ and Ly6G+ cells) and reduced levels of KC, TNF‐α, IL‐1β, and IL‐12 p40 when compared with control mice. The treatment restored cytokine levels. After 14 days, diabetic mice showed late wound closure, persistent inflammation and delayed reepithelialization, accompanied by an increase in MIG+/CD206? macrophages whereas CD206+/MIG? macrophages were decreased. Cytokines IL‐12p40, TNF‐α, IL‐1β, and KC were increased and normal levels were restored after treatment with antioxidants. These results suggest that oxidative stress plays a major role in diabetic wound healing impairment and the oral administration of antioxidants improves healing by modulating inflammation and the antioxidant system with no effect on glycemia. 相似文献
64.
Marcelo S. M. Faria José E. de Aguilar-Nascimento Osvânio S. Pimenta Luis C. AlvarengaJr Diana B. Dock-Nascimento Natasha Slhessarenko 《World journal of surgery》2009,33(6):1158-1164
Background Studies showing the improvement of insulin sensitivity by reducing the term of preoperative fasting are mostly done in patients
undergoing major operations. More information about the role of shortened preoperative fasting in perioperative metabolism
is needed for such elective minor/moderate abdominal procedures as laparoscopic cholecystectomy. We investigated the influence
of a carbohydrate-rich drink given 2 h before laparoscopic cholecystectomy on insulin resistance and the metabolic response
to trauma.
Methods A group of 21 female candidates (18–65 years old) for elective laparoscopic cholecystectomy were randomized to either an 8 h
fasting group (control group: n = 10) or to a group receiving 200 ml of a carbohydrate beverage containing 12.5% (25 g, 50 kcal per 100 ml and approximately
285 mOsm) of maltodextrine 2 h before operation (CHO group: n = 11). Blood samples for various biochemical assays were collected both at induction of anesthesia and after the 10th postoperative
hour. Insulin resistance was assessed by the HOMA-IR equation (Insulin (μU/ml) × blood glucose (mg/dl)/405).
Results There were no postoperative complications. Seventy percent (7/10) of the controls and 27.3% (3/11) of the CHO group experienced
at least one episode of vomiting (RR = 2.42, 95% Confidence Interval [CI] = 0.88–6.68; P = 0.08). Biochemical analysis showed that serum glucose (P < 0.01), insulin (P < 0.01), lactate/pyruvate ratio (P = 0.03), and triglycerides (P < 0.01) for the control group were higher than for the CHO group. The value of HOMA-IR was significantly greater (P = 0.03) in the conventionally fasted patients than in the CHO group.
Conclusions Abbreviation of the period of preoperative fasting and administration of a carbohydrate beverage diminishes insulin resistance
and the organic response to trauma. 相似文献
65.
Marcelo W. Hinojosa Brian A. Mailey Brian R. Smith Kevin M. Reavis Ninh T. Nguyen 《Surgical endoscopy》2009,23(12):2656-2656
Introduction
Gastric cardia cancer with involvement of the esophagus may require an esophagogastrectomy to obtain negative tumor margins. Multiple studies have shown that minimally invasive esophagectomy is a safe approach for the treatment of esophageal cancer [1–3]. We describe the technique of a minimally invasive Ivor–Lewis esophagectomy in a 55-year-old patient with a gastric cardia tumor. 相似文献66.
Marcelo F. Di Carli Farbod Asgarzadie Heinrich R. Schelbert Richard C. Brunken Sepehr Rokhsar Jamshid Maddahi 《Journal of nuclear cardiology》1998,5(6):558-566
Background. Stress perfusion imaging can assess effectively the amount of jeopardized myocardium, but its use for identifying underperfused but viable myocardium has yielded variable results. We evaluated the relation between measurements of myocardial perfusion at rest and during pharmacologic stress and the patterns of tissue viability as determined by positron emission tomographic (PET) imaging.Methods and Results. We studied 33 patients with coronary artery disease and left ventricular (LV) dysfunction (LV ejection fraction, 30% ± 8%). PET imaging was used to evaluate regional myocardial perfusion at rest and during pharmacologic stress with [13N]-ammonia as a flow tracer, and to delineate patterns of tissue viability (ie, perfusion-metabolism mismatch or match) using [18F]-deoxyglucose (FDG). We analyzed 429 myocardial regions, of which 229 were dysfunctional at rest. Of these, 30 had normal perfusion and 199 were hypoperfused. A severe resting defect (deficit>40% below normal) predicted lack of significant tissue viability; 31 of 35 regions (89%) had a PET match pattern denoting transmural fibrosis. Although regions with mild or moderate resting defects (deficit <40% below normal) showed evidence of metabolic activity, perfusion measurements alone failed to identify regions with PET mismatch (reflecting hibernating myocardium). Reversible stress defects were observed with slightly higher frequency in regions with a PET mismatch (10 of 37) than in those with a PET match (36 of 162) pattern of viability. A reversible stress defect was a specific (78%) marker, but was a relatively insensitive marker (27%) of viable myocardium as defined by the PET mismatch pattern.Conclusions. In patients with LV dysfunction, the severity of regional contractile abnormalities correlates with the severity of flow deficit at rest. Severe reductions in resting blood flow in these dysfunctional regions identify predominantly nonviable myocardium that is unlikely to have improved function after revascularization. Although dysfunctional myocardium with mild to moderate flow reductions contains variable amounts of viable tissue (as assessed by FDG uptake), flow measurements alone do not distinguish between regions with PET mismatch (potentially reversible dysfunction) and PET match (irreversible dysfunction). The presence of an irreversible defect on stress imaging is a relatively specific (78%) marker of PET match, whereas a reversible stress defect is a rather insensitive (27%) marker of viability, as defined by the PET mismatch pattern. 相似文献
67.
BACKGROUND: Cyclosporine (CsA) 2-h post-dose level (C2) correlates better than trough levels (C0) with the area under the curve. We evaluated the clinical impact of C2 and mycophenolate mofetil (MMF) dose in adult heart transplant patients receiving anti-thymocyte globulin (ATG) induction. METHODS: Two immunosuppressive strategies were sequentially evaluated. In Group 1 (13 patients), simultaneous C0/C2 (ng/mL) were analyzed. CsA dose monitoring was initially based on C0 : <3 months: 200-300, 4-6 months: 150-250, 6-9 months: 100-200, and on C2 thereafter (as in Group 2). In Group 2 (nine patients), C2 monitoring was implemented: <3 months: 600-800, 4-6 months: 500-700, >6 months: 400-600. All patients received ATG induction, corticosteroids, and MMF (1.0 g b.i.d. in Group 1 and 1.5 g b.i.d. in Group 2). RESULTS: Patients in Group 2 received higher MMF doses during the first trimester. C2 at 1, 3, 6, 12, 24, and 36 months was, respectively, 1199 +/- 476, 1202 +/- 587, 999 +/- 467, 664 +/- 203, 593 +/- 208, and 561 +/- 147 in Group 1, and 809 +/- 160 (p = 0.02), 644 +/- 178 (p = 0.003), 664 +/- 169 (p = 0.02), 616 +/- 221, 464 +/- 234, and 451 +/- 165 in Group 2. The incidence of acute rejection (grade > or =3A) at 6, 12, 24, and 36 months was, respectively, 38.5, 38.5, 46, and 54% in Group 1, and 11, 44, 56, and 56% in Group 2 (p = NS). At 3 months, the creatinine clearance was 25% lower in Group 1. Thereafter, renal function remained stable in both groups. CONCLUSION: Our results suggest that heart transplant patients receiving ATG induction may experience similar outcomes with either a higher C2 and a lower MMF dose or a lower C2 and a higher MMF dose. These results could be considered to design prospective studies to optimize C2 monitoring, to reduce the incidence of acute rejection without increasing the risk of renal dysfunction. 相似文献
68.
Innovation in noninvasive cardiovascular imaging is rapidly advancing our ability to image in great detail the structure and
function of the heart and vasculature, and hybrid PET-CT represents a clear example of this innovation. By providing concurrent
quantitative information about myocardial perfusion and metabolism with coronary and cardiac anatomy, hybrid imaging offers
the opportunity for a comprehensive noninvasive evaluation of the burden of atherosclerosis and its physiologic consequences
in the coronary arteries and myocardium. This integrated platform for assessing anatomy and biology offers great potential
for translating advances in molecularly targeted imaging into humans. Future investigations will refine these technologies,
establish standard protocols for image acquisition and interpretation, address the issue of cost-effectiveness, and validate
a range of clinical applications in large-scale clinical trials. 相似文献
69.
Rapid progression of midventricular obstruction in adults with double-chambered right ventricle 总被引:4,自引:0,他引:4
Oliver JM Garrido A González A Benito F Mateos M Aroca A Sanz E 《The Journal of thoracic and cardiovascular surgery》2003,126(3):711-717
OBJECTIVE: The purpose of this study was to determine the rate of progression of midventricular obstruction in adolescents and adults with double-chambered right ventricle. METHODS: Clinical and echocardiographic findings in 45 patients (mean age 26 +/- 6 years, range 15-44) diagnosed with double-chambered right ventricle were retrospectively analyzed. Twenty patients underwent surgical repair before the age of 15 years. The relationship between Doppler midventricular pressure gradient and patient age was analyzed in 25 patients without previous repair. Sequential change in midventricular obstruction was determined for patients with 2 or more Doppler echocardiographic examinations performed within at least a 2-year interval. RESULTS: Right midventricular pressure gradient in nonrepaired patients was 70 +/- 38 mm Hg (range 25-150). A significant relationship between midventricular obstruction and patient age (r = 0.64, P <.001) was found. Midventricular pressure gradient at initial evaluation was 32 +/- 27 mm Hg in 16 patients < 25 years and 73 +/- 45 mm Hg in 9 patients >/= 25 years (P <.03). After the initial study, 5 patients underwent surgical repair and 13 patients without repair were followed up for a period of 6.1 +/- 2.7 years (range 2-9), in which midventricular pressure gradient increased from 32 +/- 26 mm Hg to 67 +/- 35 mm Hg (P <.001). The slope of the change in midventricular pressure gradient was 6.2 +/- 3 mm Hg per year of follow-up. Seven more patients underwent surgical repair during follow-up due to progression of the obstruction. There was no mortality nor residual midventricular obstruction in surgically repaired patients. CONCLUSIONS: Mild right midventricular obstruction shows a fast rate of progression in adolescents and young adults. Thus, close clinical and echocardiographic follow-up is advised, and surgical repair should be considered if significant progression of obstruction is detected. 相似文献
70.
Facciuto ME Singh MK Rocca JP Rochon C Rodriguez Davalos MI Eshghi M Schwalb DM Choudhury M Sheiner PA 《World journal of surgery》2008,32(11):2403-2407
Background The potential for massive hemorrhage imposes additional challenge in the management of retroperitoneal tumors. This report
details technical considerations for the management of upper retroperitoneal tumors using principles of liver transplantation.
Methods A retrospective chart review of patients who underwent surgery for extensive retroperitoneal tumors using techniques for liver
transplantation from December 2002 to November 2007 was done.
Results Twenty-four patients (14 males and 10 females with a mean age 57 years) underwent major retroperitoneal surgery. Renal cell
carcinoma was the most common tumor seen in 17 patients. Mean tumor dimension was 12.4 cm. Abdominal exposure was achieved
via bilateral subcostal incision with upper midline extension. Right hepatic lobe mobilization and isolation from the inferior
vena cava (IVC) was performed in 23 cases. Fourteen patients had IVC involvement by tumor thrombus, which was infrahepatic
in six, retrohepatic in five, and intra-atrial in three patients. Tumor thrombus was removed by cavotomy in seven cases, resection
and plasty in four cases, IVC graft reconstruction in two cases, and one patient required IVC and atrial graft reconstruction.
Liver resection was needed in seven patients to achieve R0 resection. The Pringle maneuver was used in three patients; total
liver vascular isolation with venovenous bypass was required in two cases, transdiaphragmatic intrapericardial IVC control
in one case, and cardiopulmonary bypass in one patient. There was no intraoperative or postoperative mortality and mean length
of stay was 13 days.
Conclusion Liver transplantation surgical principles help achieve exposure and vascular control of major vascular structures that enable
safe resection of these extensive retroperitoneal tumors. 相似文献