Consentimiento Para Donar Órganos

En el número de junio de este año de la Revista Chilena de Cirugía se publica un artículo realizado por mi que realiza un análisis de dos formas de captar donantes para trasplante de órganos, se trata de los modelos de consentimiento presunto y de respuesta requerida. El link da acceso al texto en pdf.

http://www.cirujanosdechile.cl/Revista/PDF%20Cirujanos%202007_03/Cir.3_2007.(13).pdf

Lumbociatica: Cirugía vs Tratamiento Conservador

Surgery versus Prolonged Conservative Treatment for Sciatica
Wilco C. Peul, et al. for the Leiden–The Hague Spine Intervention Prognostic Study Group
N Engl J Med 2007;356(22):2245-56

Background Lumbar-disk surgery often is performed in patients who have sciatica that does not resolve within 6 weeks, but the optimal timing of surgery is not known.

Methods We randomly assigned 283 patients who had had severe sciatica for 6 to 12 weeks to early surgery or to prolonged conservative treatment with surgery if needed. The primary outcomes were the score on the Roland Disability Questionnaire, the score on the visual-analogue scale for leg pain, and the patient's report of perceived recovery during the first year after randomization. Repeated-measures analysis according to the intention-to-treat principle was used to estimate the outcome curves for both groups.

Results Of 141 patients assigned to undergo early surgery, 125 (89%) underwent microdiskectomy after a mean of 2.2 weeks. Of 142 patients designated for conservative treatment, 55 (39%) were treated surgically after a mean of 18.7 weeks. There was no significant overall difference in disability scores during the first year (P=0.13). Relief of leg pain was faster for patients assigned to early surgery (P<0.001). Patients assigned to early surgery also reported a faster rate of perceived recovery (hazard ratio, 1.97; 95% confidence interval, 1.72 to 2.22; P<0.001). In both groups, however, the probability of perceived recovery after 1 year of follow-up was 95%.

Conclusions The 1-year outcomes were similar for patients assigned to early surgery and those assigned to conservative treatment with eventual surgery if needed, but the rates of pain relief and of perceived recovery were faster for those assigned to early surgery.

UN AÑO DE "EL BISTURÍ"

Hoy se cumple un año desde que inicié este proyecto/hobby. Es complicado a veces lograr revisar y publicar artículos bien hechos sobre temas relevantes, sin embargo, el esfuerzo se ha visto retribuido por los comentarios recibidos. Reitero la invitación: si tienen algun artículo o datos médicos interesantes para el resto de nuestros colegas hagamelos llegar, así como sus comentarios para ir mejorando este blog.

Muchas gracias y un saludo
Dr. Hugo Álvarez M.

Cáncer de Vesícula: Rol de la Laparoscopía

Gallbladder Cancer: The Role of Laparoscopy and Radical Resection.
Annals of Surgery 2007; 45(6):893-901.
Shih, Samuel P; Schulick, Richard D; Cameron, John L;et al.

Objectives: We assess how laparoscopy has altered the presentation of patients with gallbladder cancer and determine whether radical resection in patients with gallbladder cancer is beneficial.

Summary Background Data: The widespread adoption of laparoscopic cholecystectomy has led to an increased frequency of incidentally discovered gallbladder carcinoma. Little data exist to guide surgeons in the optimum management of patients with gallbladder cancer, particularly with respect to the potential advantages of radical resection.

Methods: Records of 107 patients with gallbladder cancer admitted to a tertiary academic medical center between 1995 and 2004 were reviewed. Gallbladder cancer was found incidentally in 53 patients (50%). Fifty-two of these patients underwent a routine laparoscopic cholecystectomy and were found to have gallbladder cancer intraoperatively or following the operation by subsequent pathologic evaluation of the specimen. Gallbladder cancer had been diagnosed preoperatively by radiology in the other 54 patients (50%). These patients did not undergo laparoscopic cholecystectomy and were explored electively.

Results: The median age at presentation was 67 years and 66% were female. Patients who were found to have gallbladder carcinoma incidentally at laparoscopic cholecystectomy had a significant increase in survival when compared with those who were admitted electively with a known diagnosis (P < 0.001). All patients who presented with a known diagnosis had stage II or greater disease, and 36% of these were stage IV carcinomas. However, 82% of those patients who were found incidentally were stage I or II. The overall 5-year survival for all patients was 15%; those discovered incidentally at laparoscopic cholecystectomy had a 5-year survival of 33%. This difference was significant among patients with stage II carcinomas. In the laparoscopic group, there was no difference in survival between the patients who were immediately converted to an open resection when identified to have gallbladder cancer intraoperatively (n = 6) and those who had a completed laparoscopic cholecystectomy and were re-explored at a later point when found to have gallbladder cancer by subsequent pathology (n = 33). There was a significant improvement in survival in 50 patients (47%) who underwent some form of radical resection (P < 0.001). Stage for stage comparison showed that this was significant in stage II disease. Patients who underwent hepatic resection along with lymphadenectomy and extra hepatic biliary resection had similar survival compared with those who had hepatic resection and lymphadenectomy alone.

Conclusions: Laparoscopic cholecystectomy appears to have resulted in the earlier discovery of gallbladder cancer in some patients, resulting in increased probability of survival. Patients discovered with gallbladder carcinoma during a laparoscopic cholecystectomy do not have to be converted immediately to an open resection and should be referred to a tertiary care center for further exploration. Adjunctive radical surgical resection, either at the time of cholecystectomy or subsequently, increases survival significantly in early stage disease.

Aspirina para Prevenir Cancer de Colon

Aspirin and the Risk of Colorectal Cancer in Relation to the Expression of COX-2
Andrew T. Chan, M.D., M.P.H., Shuji Ogino, M.D., Ph.D., and Charles S. Fuchs, M.D., M.P.H.
N Engl J Med 2007;356(21):2131-42

Background Regular use of aspirin reduces the risk of a colorectal neoplasm, but the mechanism by which aspirin affects carcinogenesis in the colon is not well understood.

Methods We estimated cyclooxygenase-2 (COX-2) expression by immunohistochemical assay of sections from paraffin-embedded colorectal-cancer specimens from two large cohorts of participants who provided data on aspirin use from a questionnaire every 2 years. We applied Cox regression to a competing-risks analysis to compare the effects of aspirin use on the relative risk of colorectal cancer in relation to the expression of COX-2 in the tumor.

Results During 2,446,431 person-years of follow-up of 82,911 women and 47,363 men, we found 636 incident colorectal cancers that were accessible for determination of COX-2 expression. Of the tumors, 423 (67%) had moderate or strong COX-2 expression. The effect of aspirin use differed significantly in relation to COX-2 expression (P for heterogeneity=0.02). Regular aspirin use conferred a significant reduction in the risk of colorectal cancers that overexpressed COX-2 (multivariate relative risk, 0.64; 95% confidence interval [CI], 0.52 to 0.78), whereas regular aspirin use had no influence on tumors with weak or absent expression of COX-2 (multivariate relative risk, 0.96; 95% CI, 0.73 to 1.26). The age-standardized incidence rate for cancers that overexpressed COX-2 was 37 per 100,000 person-years among regular aspirin users, as compared with 56 per 100,000 person-years among those who did not use aspirin regularly; in contrast, the rate for cancers with weak or absent COX-2 expression was 27 per 100,000 person-years among regular aspirin users, as compared with 28 per 100,000 person-years among nonregular aspirin users.

Conclusions Regular use of aspirin appears to reduce the risk of colorectal cancers that overexpress COX-2 but not the risk of colorectal cancers with weak or absent expression of COX-2.

Comparación entre Técnicas para Tratamiento de Incontinencia Urinaria de Estres

Burch Colposuspension versus Fascial Sling to Reduce Urinary Stress Incontinence
Michael E. Albo, et al., for the Urinary Incontinence Treatment Network
N Engl J Med 2007;356(21):2143-55

Background Many surgical procedures are available for women with urinary stress incontinence, yet few randomized clinical trials have been conducted to provide a basis for treatment recommendations.

Methods We performed a multicenter, randomized clinical trial comparing two procedures — the pubovaginal sling, using autologous rectus fascia, and the Burch colposuspension — among women with stress incontinence. Women were eligible for the study if they had predominant symptoms associated with the condition, a positive stress test, and urethral hypermobility. The primary outcomes were success in terms of overall urinary-incontinence measures, which required a negative pad test, no urinary incontinence (as recorded in a 3-day diary), a negative cough and Valsalva stress test, no self-reported symptoms, and no retreatment for the condition, and success in terms of measures of stress incontinence specifically, which required only the latter three criteria. We also assessed postoperative urge incontinence, voiding dysfunction, and adverse events.

Results A total of 655 women were randomly assigned to study groups: 326 to undergo the sling procedure and 329 to undergo the Burch procedure; 520 women (79%) completed the outcome assessment. At 24 months, success rates were higher for women who underwent the sling procedure than for those who underwent the Burch procedure, for both the overall category of success (47% vs. 38%, P=0.01) and the category specific to stress incontinence (66% vs. 49%, P<0.001). However, more women who underwent the sling procedure had urinary tract infections, difficulty voiding, and postoperative urge incontinence.

Conclusions The autologous fascial sling results in a higher rate of successful treatment of stress incontinence but also greater morbidity than the Burch colposuspension.

Quimioprofilaxis para Viajeros contra la Malaria

Controversies and Misconceptions in Malaria Chemoprophylaxis for Travelers
Lin H. Chen, MD; Mary E. Wilson, MD; Patricia Schlagenhauf, PhD
JAMA. 2007;297:2251-63.

Context Controversies in malaria prevention arise from the absence of data, conflicting data between different studies, conflicting recommendations, deviation of local practice from scientific data, and varying risk thresholds. Misconceptions about the seriousness of malaria, the tolerability of chemoprophylaxis drugs, and the efficacy and safety of repellents contribute to the controversies.

Objectives To compare several national guidelines on malaria chemoprophylaxis to identify variations in recommendations. We reviewed studies on tolerability of mefloquine with particular focus on its neuropsychiatric adverse effects and influence on performance. We also describe why most recommended chemoprophylactic regimens fail to prevent relapses of Plasmodium vivax malaria and review available options.

Evidence Acquisition We searched scientific publications in MEDLINE via PubMED for relevant articles with a cutoff date of December 2006 using the search terms malaria, chemoprophylaxis, travel, mefloquine, neuropsychiatric adverse events, tolerability, vivax malaria, and primaquine. Additional references were obtained from bibliographies of the selected articles. There were no language restrictions.

Evidence Synthesis Gaps and conflicts exist among current guidelines. Health authorities vary in the chemoprophylaxis drugs they recommend, the indications for continuous prophylaxis vs no prophylaxis, and the use of standby emergency treatment. Despite widespread reports on the adverse effects of mefloquine, controlled studies found that serious neuropsychiatric adverse events occur at rates comparable with or lower than other chemoprophylaxis drugs. Moreover, mefloquine does not appear to impair performance while driving, flying, or diving. Vivax malaria causes significant illness in travelers, but current first-line chemoprophylaxis agents do not prevent relapses of vivax malaria. Although not licensed in most countries as primary prophylaxis, primaquine effectively prevents relapses of vivax malaria.

Conclusions Prevention of malaria in travelers requires detailed knowledge of malaria epidemiology and host-vector-parasite interactions. Decisions are complicated by a lack of standardized recommendations, controversies, and misconceptions. Improved international consensus is indicated to minimize conflicting guidelines, clarify controversies, and promote adherence to preventive measures.

Efectos Cardiovasculares Adversos con Rosiglitazona

Effect of Rosiglitazone on the Risk of Myocardial Infarction and Death from Cardiovascular Causes
Steven E. Nissen, M.D., and Kathy Wolski, M.P.H.
N Engl J Med 2007

Background
Rosiglitazone is widely used to treat patients with type 2 diabetes mellitus, but its effect on cardiovascular morbidity and mortality has not been determined.

Methods
We conducted searches of the published literature, the Web site of the Food and Drug Administration, and a clinical-trials registry maintained by the drug manufacturer (GlaxoSmithKline). Criteria for inclusion in our meta-analysis included a study duration of more than 24 weeks, the use of a randomized control group not receiving rosiglitazone, and the availability of outcome data for myocardial infarction and death from cardiovascular causes. Of 116 potentially relevant studies, 42 trials met the inclusion criteria. We tabulated all occurrences of myocardial infarction and death from cardiovascular causes.

Results
Data were combined by means of a fixed-effects model. In the 42 trials, the mean age of the subjects was approximately 56 years, and the mean baseline glycated hemoglobin level was approximately 8.2%. In the rosiglitazone group, as compared with the control group, the odds ratio for myocardial infarction was 1.43 (95% confidence interval [CI], 1.03 to 1.98; P=0.03), and the odds ratio for death from cardiovascular causes was 1.64 (95% CI, 0.98 to 2.74; P=0.06).

Conclusions
Rosiglitazone was associated with a significant increase in the risk of myocardial infarction and with an increase in the risk of death from cardiovascular causes that had borderline significance. Our study was limited by a lack of access to original source data, which would have enabled time-to-event analysis. Despite these limitations, patients and providers should consider the potential for serious adverse cardiovascular effects of treatment with rosiglitazone for type 2 diabetes.

Manejo y Diagnostico de Perforaciones Duodenales y Biliares tras ERCP

Pancreaticobiliary and Duodenal Perforations After Periampullary Endoscopic Procedures Diagnosis and Management
Javairiah Fatima; Todd Baron; Mark Topazian; Scott Houghton; Corey Iqbal; Beverly Ott; David Farley; Michael Farnell; Michael Sarr.
Arch Surg. 2007;142:448-455.

Objective To review our experience with management of pancreaticobiliary and duodenal (PB/D) perforations after periampullary endoscopic interventions. Although pancreaticobiliary and duodenal perforations after periampullary endoscopic procedures are rare, their management has not been well described.

Patients Individuals who experienced pancreaticobiliary and duodenal perforations.

Main Outcome Measures Comorbidities, interventions performed, mechanism/site of perforation, management, and hospital morbidity/mortality.

Results Seventy-five perforations (0.6%) occurred in 12 427 procedures; 20 perforations (27%) occurred during biliary stricture dilatation, 18 (24%) during diagnostic endoscopic retrograde cholangiopancreatography, and 15 (20%) during management of choledocholithiasis. Perforations were caused by guidewire insertion in 24 patients (32%), sphincterotomy in 11 (15%), passage of the endoscope in 8 (11%), or stent migration in 7 (9%) and were identified during the index procedure in 45 patients (60%). Delayed presentations included pain in 33 patients (44%), leukocytosis in 26 (35%), and/or fever in 13 (17%) and were diagnosed using computed tomography in 19 patients (25%) and abdominal radiography in 10 (13%); 9 cases (12%) were diagnosed more than 24 hours after the procedure. Indications for operative treatment were gaping duodenal perforations and perforations in patients with surgically altered anatomy. Indications for nonoperative management included contained bile duct perforations and focal duodenal perforations. Management was nonoperative in 53 patients (71%) and operative in 22 (29%). Patients with duodenal perforations, higher American Society of Anesthesia status (P<.01 each), and older age (mean ± SEM, 65 ± 4 vs 55 ± 2 years; P = .02) were more likely to require operative management. Hospital stay (mean ± SEM, 16 ± 4 vs 4 ± 1 days; P<.05) and mortality (13% vs 4%; P<.05) were greater in operative patients (P<.05 each).

Conclusions Most (70%) pancreaticobiliary and duodenal perforations secondary to periampullary endoscopic interventions can be managed nonoperatively. Most biliary perforations can be managed nonoperatively; a requirement for operative treatment increases the mortality rate.

Utilidad de Pet-Scan con 18-F-Fluordeoxyglucosa en la Evaluación de Lesiones Quísticas del Pancreas

The Utility of F-18 Fluorodeoxyglucose Whole Body PET Imaging for Determining Malignancy in Cystic Lesions of the Pancreas
Journal of Gastrointestinal Surgery 2006;10(10):1354-60

John C. Mansour, Lawrence Schwartz, Neeta Pandit-Taskar, Michael D'Angelica, Yuman Fong, Steven M. Larson, Murray F. Brennan and Peter J. Allen.

Memorial Sloan-Kettering Cancer Center.

Previous studies have suggested that whole body positron-emission tomography (PET) can distinguish between benign and malignant cysts of the pancreas. Patients were identified (n = 68) who had undergone whole body PET imaging for a cystic lesion of the pancreas between Jan. 1997 and May 2005. Cross-sectional imaging studies were reviewed by a single blinded radiologist, and positive PET studies were reviewed by a blinded nuclear medicine physician.

Operative resection was performed in 21 patients (31%), and 47 patients were managed with radiographic follow-up. F-18 Fluorodeoxyglucose (FDG)-avid lesions were identified in eight of the 68 patients (12%). Within the resected group of patients (n = 21), four of the seven patients (57%) with either in situ or invasive malignancy (adenocarcinoma: 3 of 5, papillary mucinous carcinoma: 1 of 2) had positive PET imaging (mean SUV, 5.9; range 2.5–8.0), and 2 of the 14 patients (14%) with benign lesions had positive PET imaging (serous cystadenoma, n = 1, SUV = 3.3; pseudocyst n = 1, SUV = 2.7). All lesions proven to be malignant with increased FDG uptake had highly suspicious findings on cross-sectional imaging. Within the group of resected patients, the sensitivity of PET for identifying malignant pathology was 57%, and the specificity was 85%.

The sensitivity and specificity of PET for malignancy in this study was lower than previously reported, and PET findings did not identify otherwise occult malignant cysts. We do not believe whole body FDG-PET to be essential in the evaluation of cystic lesions of the pancreas.

Revisión sobre Pancreatectomía Distal con Conservación Esplénica

Distal pancreatectomy with splenic preservation revisited.
Surgery 2007; 141(5):619-625
J. Rubén Rodríguez, Michael G. Madanat, Brian C. Healy, Sarah P. Thayer, Andrew L. Warshaw Carlos Fernández-del Castillo

Background
Splenic preservation (SP) during distal pancreatectomy can be accomplished by ligating the main splenic artery and vein relying on blood supply from the short gastric vessels. The purpose of this study was to examine the short-term implications of this operation, comparing it to the outcomes following distal pancreatectomy with splenectomy.

Methods
The records of 259 patients who underwent distal pancreatectomy with and without SP at Massachusetts General Hospital from 1994 to 2004 were reviewed.

Results
A total of 29% of patients underwent SP with this technique. These patients were more likely to be women (74% vs 56%, P = .008) and to have benign disease (93% vs 54%, P < .0001). Their operative times were shorter (2.5 vs 3.1 h, P < .0001), they had less blood loss (300 vs 500 ml, P < .0001) and a shorter duration of stay (6 days [interquartile range, 5 to 7] vs 7 days [interquartile range, 5 to 8], P = .001). SP was not a significant predictor of complications in either univariate (P = .445) or adjusted analysis (P = .543). One patient (1.4%) in the SP group was reoperated for splenic infarction and two patients (1.1%) in the splenectomy group for abscess and hemorrhage. There were 2 (0.8%) postoperative deaths, both in the splenectomy group.

Conclusions
Splenic preservation relying on blood supply from the short gastric vessels is reliable and safe and does not have a higher incidence of postoperative complications when compared to traditional distal pancreatectomy with splenectomy. The current series validates this approach and provides further evidence of its feasibility and safety

Reconstrucción Esofágica con Coloplastía Derecha tras Ingesta de Caústicos

Esophageal reconstruction after caustic injury: is there still a place for right coloplasty?

The American Journal of Surgery 2007;193(6):660-664

Hervé Bothereau M, Nicolas Munoz-Bongrand, Benoît Lambert, Sébastino Montemagno, Pierre Cattan and Emile Sarfati
Department of Digestive and Endocrine Surgery, Saint-Louis Hospital,Paris, France

Background

Through a systematic policy of using the right colon as an esophageal substitute, the authors analyze the reliability of this transplant for reconstruction after digestive caustic injury.

Methods

From 1995 to 2005, a right coloplasty was attempted in 81 patients after total esophagogastrectomy (n = 57) or for esophageal stricture (n = 24).

Results

The use of the right colon was not possible in 10 patients (12%) because of insufficient blood supply. In addition, postoperative right colic graft necrosis occurred in 5 patients. Cervical fistula occurred in 25 patients (31%). Opening of the thoracic inlet was associated with a lower rate of this complication (P = .04). At the end of the follow-up, 71 patients (88%) recovered oral feeding.

Conclusion

Attempt to use the right colon as an esophageal substitute failed in 18% of the patients. Despite high rates of cervical complications, in part linked to the peculiar setting of caustic injury, functional results remains satisfactory.

Hernioplastia con Malla: Comparación de Resultados en Cirugía Electiva vs Urgencia

Are the outcomes of emergency Lichtenstein hernioplasty similar to the outcomes of elective Lichtenstein hernioplasty?
Marcelo A. Beltrán and Karina S. Cruces. Department of Surgery, Emergency Unit, Hospital de Ovalle, Chile.
International Journal of Surgery 2007; 5 (3): 198-204

Background
The safe use of polypropylene prosthesis for the repair of complicated inguinal hernias has been established even when small bowel resection was required. Few reports have completely addressed this subject; none have compared the outcomes of emergency and elective Lichtenstein hernioplasty.

Methods
From January 2001 to December 2003, 343 patients were electively operated for inguinal hernia and 62 for complicated inguinal hernia. A follow-up period of 17–57 months using the Quantitative and Qualitative Measurement Instrument for evaluation of Lichtenstein hernioplasty outcomes (QQMI) was completed for 48 emergency patients and 326 elective patients.

Results
The mean QQMI score showed that most patients felt that the outcomes of their surgery were very good or excellent. Mean QQMI score for elective surgery was 10.1 and 9.5 for emergency surgery.

Conclusions
The outcomes of emergency Lichtenstein hernioplasty were inferior to the outcomes of elective Lichtenstein hernioplasty.

Complicaciones Abdominales Según Técnica Utilizada para Reparar Hernia Diafragmatica Congénita

Abdominal Complications Related to Type of Repair for Congenital Diaphragmatic Hernia
Journal of Surgical Research 2007; 140(2): 234-236
Shawn D. St. Peter, Patricia A. Valusek, KuoJen Tsao, George W. Holcomb III, Daniel J. Ostlie and Charles L. Snyder

Background
Literature on congenital diaphragmatic hernia (CDH) over the past few decades has focused on prognostic factors and management of pulmonary hypertension/hypoplasia. Larger diaphragmatic defects may require patch closure, reported by some authors to be associated with poorer outcomes. In this study, we evaluate the impact synthetic material has on the need for subsequent abdominal operations, particularly recurrence and small bowel obstruction (SBO).

Methods
After obtaining IRB approval, all patients undergoing repair of congenital diaphragmatic from January, 1994 to December, 2004 were investigated. Records from primary and subsequent admissions were reviewed to identify those patients who underwent major procedures after repair of the diaphragmatic defect. Subsequent abdominal operations in these series were recurrent CDH repair, exploration for SBO and fundoplication. Patients who died prior to hospital discharge were excluded. Statistical comparisons were made using Fisher’s exact test: significance was defined as P < 0.05.

Results
During the study period, there were 81 survivors from CDH repair, 24 with a synthetic patch, and 57 without. Those with a patch repair had a significantly increased risk of recurrence, small bowel obstruction, and subsequent operation. Eleven patients had nonabsorbable mesh patches, and 13 were repaired with absorbable (Surgisis-Gold; Cook Technology Inc., West Lafayette, IN). While there were no differences in recurrence between these two groups, four patients (31%) with Surgisis developed SBO compared with one patient (9%) repaired with a nonabsorbable synthetic.

Conclusions
Incidence of SBO and recurrent CDH in patients with a patch was higher than those who underwent primary repair. There may also be a difference in the rate of subsequent SBO depending on the type of mesh used. A prospective trial is under way at our institution to help define this issue.

Displasia en Esofago de Barrett

Al hacer click en el título de este entry tendran acceso a la primera parte de esta revisión respecto a la displasia de alto grado en el Esofago de Barrett publicado en la Revista Chilena de Cirugía.
Español. PDF

Tomografia Computada en Manejo Conservador del Trauma Esplénico

The Utility of Serial Computed Tomography Imaging of Blunt Splenic Injury: Still Worth a Second Look?
Journal of Trauma-Injury Infection & Critical Care. 62(5):1143-1148, May 2007.
Weinberg, Jordan A; Magnotti, Louis J; Croce, Martin A; Edwards, Norma M; Fabian, Timothy

Background: Serial computed tomography (CT) imaging of blunt splenic injury (BSI) can identify the latent formation of splenic artery pseudoaneurysms (PSAs), contributing to improved success in splenic salvage. The practice of serial CT imaging, however, has not been embraced. The purpose of this study was to reevaluate the clinical practice of serial CT imaging within the context of an institutional protocol for the nonoperative management (NOM) of BSI.

Method: Consecutive patients with BSI selected for NOM were identified from our trauma registry. Patients were managed according to protocol, whereby hemodynamically stable patients with PSA on initial or follow-up CT imaging were referred for angiography. Follow-up CT was performed 24 to 48 hours after the initial CT. Data were abstracted from hospital, clinic, and radiology records, and included age, Injury Severity Score, splenic injury grade (SIG), and CT findings. The incidence and timing of PSA identification with respect to subsequent management and outcome were reviewed.

Results: Of 426 BSI admissions during a 2.5-year period, 341 (80%) were selected for NOM. Mean follow-up was 39 days, with 76% followed for >=7 days. Serial CT imaging resulted in the angiographic detection of 14 (4%) early PSAs and 11 (3%) latent PSAs. PSAs were associated with increasing SIG (p < 0.001); however, 24% of PSAs were observed in SIG 1 and 2. Embolization was successful in 13 of 14 (93%) patients with early PSAs and 10 of 11 (91%) with latent PSAs. The splenic salvage rate for all patients selected for NOM during the study period was 329 of 341 (97%).

Conclusions: Adherence to a NOM protocol guided by serial CT imaging has resulted in one of the highest splenic salvage rates reported to date. Identification and embolization of latent PSA likely contributes to NOM success, given the unfavorable natural history of these lesions. Although PSA formation is correlated with increasing SIG, PSAs are not exclusive to higher-grade injury, warranting serial CT surveillance regardless of SIG

Información de Seguridad Referente a Bevacizumab

Avastin (bevacizumab)

Genentech and FDA notified healthcare professionals of important new safety information regarding tracheoesophageal (TE) fistula formation in a recent clinical study in patients with limited-stage small cell lung cancer (SCLC).

This multicenter, non-randomized, single-arm phase II clinical trial study combined chemotherapy and radiation plus Avastin.

There have been two confirmed serious adverse events of TE fistula (one fatal) reported in the first 29 patients enrolled in this study. A third, fatal event (upper aerodigestive tract hemorrhage and death of unknown cause), was also reported, in which TE fistula was suspected but not confirmed. All three events occurred during the Avastin maintenance phase of the study in the context of persistent esophagitis.

Additionally, six other cases of TE fistula have also been reported in other lung and esophageal cancer studies using Avastin and chemotherapy alone or with concurrent radiation treatment.

Avastin is not approved for the treatment of SCLC.

The current prescribing information includes a description of gastrointestinal tract fistula formation in patients with colorectal cancer and other types of cancer treated with Avastin.

Genentech intends to revise the Avastin package insert to include more detailed information regarding the incidence of all cases of fistula in patients treated with Avastin.

Efecto de Alimentación Precoz Sobre Ileo Post Operatorio: Un Estudio Randomizado

Randomized clinical trial of the impact of early enteral feeding on postoperative ileus and recovery
British Journal of Surgery 2007; 94(5):555-61
I. J. M. Han-Geurts, W. C. J. Hop, N. F. M. Kok, A. Lim, K. J. Brouwer, J. Jeekel

Abstract
Postoperative convalescence is mainly determined by the extent and duration of postoperative ileus. This randomized clinical trial evaluated the effects of early oral feeding on functional gastrointestinal recovery and quality of life.

One hundred and twenty-eight patients undergoing elective open colorectal or abdominal vascular surgery participated in the trial. Of these, 67 were randomized to a conventional return to diet, and 61 to a regimen allowing resumption of an oral diet as soon as tolerated (free diet group).

Reinsertion of a nasogastric tube was necessary in 20 per cent of the free diet group and 10 per cent of the conventional group (P = 0·213). The complication rate was similar for both groups, as was return of gastrointestinal function. A normal diet was tolerated after a median of 2 days in the free diet group compared with 5 days in the conventional group (P <>

Early resumption of oral intake does not diminish the duration of postoperative ileus or lead to a significantly increased rate of nasogastric tube reinsertion. Tolerance of oral diet is not influenced by gastrointestinal functional recovery.

As there is no reason to withhold oral intake following open colorectal or abdominal vascular surgery, postoperative management should include early resumption of diet

Relación entre Virus Papiloma Humano y Cáncer Orofaringeo

Case–Control Study of Human Papillomavirus and Oropharyngeal Cancer
N Engl J Med 2007; 356(19) :1944-1956
Gypsyamber D'Souza, Ph.D., Aimee R. Kreimer, Ph.D., Raphael Viscidi, M.D., Michael Pawlita, M.D., Carole Fakhry, M.D., M.P.H., Wayne M. Koch, M.D., William H. Westra, M.D., and Maura L. Gillison, M.D., Ph.D.

Background Substantial molecular evidence suggests a role for human papillomavirus (HPV) in the pathogenesis of oropharyngeal squamous-cell carcinoma, but epidemiologic data have been inconsistent.

Methods We performed a hospital-based, case–control study of 100 patients with newly diagnosed oropharyngeal cancer and 200 control patients without cancer to evaluate associations between HPV infection and oropharyngeal cancer. Multivariate logistic-regression models were used for case–control comparisons.

Results A high lifetime number of vaginal-sex partners (26 or more) was associated with oropharyngeal cancer (odds ratio, 3.1; 95% confidence interval [CI], 1.5 to 6.5), as was a high lifetime number of oral-sex partners (6 or more) (odds ratio, 3.4; 95% CI, 1.3 to 8.8). The degree of association increased with the number of vaginal-sex and oral-sex partners (P values for trend, 0.002 and 0.009, respectively). Oropharyngeal cancer was significantly associated with oral HPV type 16 (HPV-16) infection (odds ratio, 14.6; 95% CI, 6.3 to 36.6), oral infection with any of 37 types of HPV (odds ratio, 12.3; 95% CI, 5.4 to 26.4), and seropositivity for the HPV-16 L1 capsid protein (odds ratio, 32.2; 95% CI, 14.6 to 71.3). HPV-16 DNA was detected in 72% (95% CI, 62 to 81) of 100 paraffin-embedded tumor specimens, and 64% of patients with cancer were seropositive for the HPV-16 oncoprotein E6, E7, or both. HPV-16 L1 seropositivity was highly associated with oropharyngeal cancer among subjects with a history of heavy tobacco and alcohol use (odds ratio, 19.4; 95% CI, 3.3 to 113.9) and among those without such a history (odds ratio, 33.6; 95% CI, 13.3 to 84.8). The association was similarly increased among subjects with oral HPV-16 infection, regardless of their tobacco and alcohol use. By contrast, tobacco and alcohol use increased the association with oropharyngeal cancer primarily among subjects without exposure to HPV-16.

Conclusions Oral HPV infection is strongly associated with oropharyngeal cancer among subjects with or without the established risk factors of tobacco and alcohol use.

Dosis de Aspirina para Prevención de Eventos Cardiovasculares

Aspirin Dose for the Prevention of Cardiovascular Disease
A Systematic Review
Charles L. Campbell, MD; Susan Smyth, MD, PhD; Gilles Montalescot, MD, PhD; Steven R. Steinhubl, MD
JAMA. 2007;297:2018-2024.

Context More than 50 million US adults take aspirin regularly for long-term prevention of cardiovascular disease, typically either 81 mg/d or 325 mg/d. Controversy remains regarding the most appropriate long-term daily dose.

Objective To review the mechanism of action of aspirin and the clinical literature for relationships among aspirin dosage, efficacy, and safety.

Evidence Acquisition A systematic review of the English-language literature was undertaken using MEDLINE and EMBASE (searched through February 2007) and the search term aspirin or acetylsalicylic acid and dose. The search was limited to clinical trials and was extended by a review of bibliographies of pertinent reports of original data and review articles. Published prospective studies using different aspirin dosages in the setting of cardiovascular disease were included.

Evidence Synthesis Although pharmacodynamic data demonstrate that long-term aspirin dosages as low as 30 mg/d are adequate to fully inhibit platelet thromboxane production, dosages as high as 1300 mg/d are approved for use. In the United States, 81 mg/d of aspirin is prescribed most commonly (60%), followed by 325 mg/d (35%). The available evidence, predominantly from secondary-prevention observational studies, supports that dosages greater than 75 to 81 mg/d do not enhance efficacy, whereas larger dosages are associated with an increased incidence of bleeding events, primarily related to gastrointestinal tract toxicity.

Conclusions Currently available clinical data do not support the routine, long-term use of aspirin dosages greater than 75 to 81 mg/d in the setting of cardiovascular disease prevention. Higher dosages, which may be commonly prescribed, do not better prevent events but are associated with increased risks of gastrointestinal bleeding.

Preparación de Colon

Preparar el colon para la cirugía. ¿Necesidad real o nada más (y nada menos) que el peso de la tradición?
José V Roiga Juan García-Armengola Rafael Alósb Amparo Solanab Rodolfo Rodríguez-Carrilloc Pablo Galindod M Isabel Fabrad Alberto López-Delgadod José García-Romerod
Rev Cir Esp 2007; 81(5):240-6

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Resumen
La preparación mecánica del colon es un componente tradicional del preoperatorio de los pacientes sometidos a cirugía colorrectal dirigido a reducir sus complicaciones infecciosas, ya que clásicamente la presencia de heces en el colon se ha asociado a contaminación intraoperatoria y dehiscencias anastomóticas. Sin embargo, en la actualidad, estudios tanto experimentales como de observaciones clínicas, trabajos prospectivos y revisiones sistemáticas de la literatura cuestionan su utilidad.
Se efectúa una revisión de conjunto sobre el tema, y se concluye que, con la evidencia disponible, no está claro el beneficio de la preparación mecánica del colon y hay trabajos que muestran incluso una mayor incidencia de complicaciones en la tasa de dehiscencia anastomótica y la morbilidad con su uso sistemático, por lo que puede ser omitida en cirugía electiva y es adecuado restringirla a indicaciones concretas, como pequeños tumores, para facilitar su localización durante un abordaje laparoscópico o cuando se precise hacer una endoscopia intraoperatoria. El papel de la preparación mecánica en la cirugía rectal no está aclarado en la actualidad y se precisa de series más amplias para establecerlo.

Estreptokinasa Intracoronaria Post Angioplastia Coronaria Primaria

Intracoronary Streptokinase after Primary Percutaneous Coronary Intervention
N Engl J Med 2007; 356(18):1823-34
Murat Sezer, M.D., Hüseyin Oflaz, M.D., Taner Gören, M.D., rem Okçular, M.D., Berrin Umman, M.D., Yilmaz Nianci, M.D., Ahmet Kaya Bilge, M.D., Yasemin anli, M.D., Mehmet Meriç, M.D., and Sabahattin Umman, M.D.

Background Microvascular perfusion is often impaired after primary percutaneous coronary intervention (PCI). We proposed that in situ thrombosis might contribute to poor myocardial perfusion in this setting. To test this hypothesis, we evaluated the effect of low-dose intracoronary streptokinase administered immediately after primary PCI.

Methods Forty-one patients undergoing primary PCI were randomly assigned to receive intracoronary streptokinase (250 kU) or no additional therapy. Two days later, cardiac catheterization was repeated, and coronary hemodynamic end points were measured with the use of a guidewire tipped with pressure and temperature sensors. In patients with anterior myocardial infarction, the deceleration time of coronary diastolic flow was measured with transthoracic echocardiography. At 6 months, angiography, echocardiography, and technetium-99m single-photon-emission computed tomography were performed.

Results Two days after PCI, all measures of microvascular function (means ±SD) were significantly better in the streptokinase group than in the control group, including coronary flow reserve (2.01±0.57 vs. 1.39±0.31), the index of microvascular resistance (16.29±5.06 U vs. 32.49±11.04 U), the collateral-flow index (0.08±0.05 vs. 0.17±0.07), mean coronary wedge pressure (10.81±5.46 mm Hg vs. 17.20±7.93 mm Hg), systolic coronary wedge pressure (18.24±6.07 mm Hg vs. 33.80±11.00 mm Hg), and diastolic deceleration time (828±258 msec vs. 360±292 msec). The administration of intracoronary streptokinase was also associated with a significantly lower corrected Thrombolysis in Myocardial Infarction frame count (the number of cine frames required for dye to travel from the ostium of a coronary artery to a standardized distal coronary landmark) at 2 days. At 6 months, however, there was no evidence of a difference between the two study groups in left ventricular size or function.

Conclusions In our pilot trial, the administration of low-dose intracoronary streptokinase immediately after primary PCI improved myocardial reperfusion but not long-term left ventricular size or function. These findings require clarification in a larger trial.

Efecto de la Malla de Poliglactina sobre la Formación de Adherencias entre Visceras y Malla de Polipropileno: Un Modelo Animal

Interposition of Polyglactin Mesh Does Not Prevent Adhesion Formation Between Viscera and Polypropylene Mesh
Tammo S. de Vries Reilingh, Harry van Goor, Manuel J. Koppe, Maarten E. Bodegom, Thÿs Hendriks and Robert P. Bleichrodt
Journal of Surgical Research 2007; 140(1):27-30

Background
The use of intra-peritoneal polypropylene mesh (PPM) to repair incisional hernia carries the risk of adhesions and damage to the intra-abdominal viscera. Polyglactin 910 mesh (PGM) is advocated to avoid contact between PPM and the intra-abdominal viscera. An experimental study in rats was performed to determine if interposition of a resorbable prosthesis between the PPM and viscera alters biocompatibility, adhesion formation, and herniation.

Materials and methods
A 2- × 3-cm abdominal wall defect was created in 80 rats. Rats were randomly assigned for repair with 2.5- × 3.5-cm PPM (n = 40) or 2.5- × 3.5-cm PPM plus polyglactin 910 mesh (PPM-PGM) (n = 40). The rats were sacrificed at 1, 2, 3, and 6 months (n = 10), and an autopsy was performed to determine herniation and adhesion rates. Mesh-fascia interface was taken for histology.

Results
In the PPM group, 1 rat died before the end of the experiment, and at 6 months one of the 10 rats had a herniation. In the PPM-PGM group, two rats died before the end of the experiment, and two rats had a herniation after 1 month and three rats after 6 months. At 1, 2, and 3 months the adhesion score in the PPM group (median, 3; range, 2–3) did not differ from the score in the PPM-PGM group (median, 3; range, 2–3). Also, at 6 months the adhesion score in the PPM group (median, 2; range, 2–3) did not differ from the score in the PPM-PGM group (median, 3; range, 2–3). At microscopy a capsule was formed around the PP fibers, which matured over months in the PPM group. In the first month after implantation an inflammatory response was seen. Histology was similar in both groups, although in the early PPM-PGM group the inflammatory response was more evident.

Conclusion
Interposition of PGM between PPM and viscera does not alter adhesion formation nor influences herniation rate.

Levosidesmendan vs Dobutamina en Insuficiencia Cardíaca Descompensada: ESTUDIO SURVIVE

Levosimendan vs Dobutamine for Patients With Acute Decompensated Heart Failure
The SURVIVE Randomized Trial
Alexandre Mebazaa, MD, PhD; Markku S. Nieminen, MD, PhD; Milton Packer, MD; Alain Cohen-Solal, MD, PhD; Franz X. Kleber, MD; Stuart J. Pocock, PhD; Roopal Thakkar, MD; Robert J. Padley, MD; Pentti Põder, MD, PhD; Matti Kivikko, MD, PhD; for the SURVIVE Investigators
JAMA. 2007;297:1883-1891.

Context Because acute decompensated heart failure causes substantial morbidity and mortality, there is a need for agents that at least improve hemodynamics and relieve symptoms without adversely affecting survival.

Objective To assess the effect of a short-term intravenous infusion of levosimendan or dobutamine on long-term survival.
Design, Setting, and Patients The Survival of Patients With Acute Heart Failure in Need of Intravenous Inotropic Support (SURVIVE) study was a randomized, double-blind trial comparing the efficacy and safety of intravenous levosimendan or dobutamine in 1327 patients hospitalized with acute decompensated heart failure who required inotropic support. The trial was conducted at 75 centers in 9 countries and patients were randomized between March 2003 and December 2004.

Interventions Intravenous levosimendan (n = 664) or intravenous dobutamine (n = 663).

Main Outcome Measure All-cause mortality at 180 days.

Results All-cause mortality at 180 days occurred in 173 (26%) patients in the levosimendan group and 185 (28%) patients in the dobutamine group (hazard ratio, 0.91; 95% confidence interval, 0.74-1.13; P = .40). The levosimendan group had greater decreases in B-type natriuretic peptide level at 24 hours that persisted through 5 days compared with the dobutamine group (P<.001 for all time points). There were no statistical differences between treatment groups for the other secondary end points (all-cause mortality at 31 days, number of days alive and out of the hospital, patient global assessment, patient assessment of dyspnea at 24 hours, and cardiovascular mortality at 180 days). There was a higher incidence of cardiac failure in the dobutamine group. There were higher incidences of atrial fibrillation, hypokalemia, and headache in the levosimendan group.

Conclusion Despite an initial reduction in plasma B-type natriuretic peptide level in patients in the levosimendan group compared with patients in the dobutamine group, levosimendan did not significantly reduce all-cause mortality at 180 days or affect any secondary clinical outcomes.

MicroRNA ¿Examen a Futuro para Distinguir Entre Adenocarcinoma y Pancreatitis Crónica?

MicroRNA Expression Patterns to Differentiate Pancreatic Adenocarcinoma From Normal Pancreas and Chronic Pancreatitis
Mark Bloomston, MD; Wendy L. Frankel, MD; Fabio Petrocca, MD; Stefano Volinia, PhD; Hansjuerg Alder, PhD; John P. Hagan, PhD; Chang-Gong Liu, PhD; Darshna Bhatt, BS; Cristian Taccioli, BS; Carlo M. Croce, MD
JAMA. 2007;297:1901-1908.

Context While global microRNA (miRNA) expression patterns of many embryologic, physiologic, and oncogenic processes have been described, description of the role of miRNAs in ductal adenocarcinoma of the pancreas is lacking.

Objective To define the expression pattern of miRNAs in pancreatic cancer and compare it with those of normal pancreas and chronic pancreatitis.

Design and Setting Specimens were obtained at a National Cancer Institute–designated comprehensive cancer center from patients with ductal adenocarcinoma of the pancreas (n = 65) or chronic pancreatitis (n = 42) (January 2000-December 2005). All patients underwent curative pancreatectomy; those with pancreatic cancer were chemotherapy-naive. RNA harvested from resected pancreatic cancers and matched benign adjacent pancreatic tissue as well as from chronic pancreatitis specimens was hybridized to miRNA microarrays.

Main Outcome Measures Identification of differentially expressed miRNAs that could differentiate pancreatic cancer from normal pancreas, chronic pancreatitis, or both, as well as a pattern of miRNA expression predictive of long-term (>24 months) survival. Significance of Analysis of Microarrays and Prediction of Analysis of Microarrays were undertaken to identify miRNAs predictive of tissue type and prognosis. P values were calculated by t test, adjusted for multiple testing. Kaplan-Meier survival curves were constructed using mean miRNA expression (high vs low) as threshold and compared by log-rank analysis.

Results Twenty-one miRNAs with increased expression and 4 with decreased expression were identified that correctly differentiated pancreatic cancer from benign pancreatic tissue in 90% of samples by cross validation. Fifteen overexpressed and 8 underexpressed miRNAs differentiated pancreatic cancer from chronic pancreatitis with 93% accuracy. A subgroup of 6 miRNAs was able to distinguish long-term survivors with node-positive disease from those dying within 24 months. Finally, high expression of miR-196a-2 was found to predict poor survival (median, 14.3 months [95% confidence interval, 12.4-16.2] vs 26.5 months [95% confidence interval, 23.4-29.6]; P = .009).

Conclusions Pancreatic cancer may have a distinct miRNA expression pattern that may differentiate it from normal pancreas and chronic pancreatitis. miRNA expression patterns may be able to distinguish between long- and short-term survivors, but these findings need to be validated in other study populations.