George C Velmahos

Harvard Medical School, Boston, Massachusetts, United States

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Publications (504)1606.98 Total impact

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    ABSTRACT: Background: Calorie/protein deficit in the surgical intensive care unit (SICU) is associated with worse clinical outcomes. It is customary to initiate enteral nutrition (EN) at a low rate and increase to goal (RAMP-UP). Increasing evidence suggests that RAMP-UP may contribute to iatrogenic malnutrition. We sought to determine what proportion of total SICU calorie/protein deficit is attributable to RAMP-UP. Materials and methods: This is a retrospective study of a prospectively collected registry of adult patients (N = 109) receiving at least 72 hours of EN in the SICU according to the RAMP-UP protocol (July 2012-June 2014). Subjects receiving only trophic feeds or with interrupted EN during RAMP-UP were excluded. Deficits were defined as the amount of prescribed calories/protein minus the actual amount received. RAMP-UP deficit was defined as the deficit between EN initiation and arrival at goal rate. Data included demographics, nutritional prescription/delivery, and outcomes. Results: EN was started at a median of 34.0 hours (interquartile range [IQR], 16.5-53.5) after ICU admission, with a mean duration of 8.7 ± 4.3 days. The median total caloric deficit was 2185 kcal (249-4730), with 900 kcal (551-1562) attributable to RAMP-UP (41%). The protein deficit was 98.5 g (27.5-250.4), with 51.9 g (20.6-83.3) caused by RAMP-UP (53%). Conclusions: In SICU patients initiating EN, the RAMP-UP period accounted for 41% and 53% of the overall caloric and protein deficits, respectively. Starting EN immediately at goal rate may eliminate a significant proportion of macronutrient deficit in the SICU.
    Full-text · Article · Dec 2015 · Nutrition in Clinical Practice
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    ABSTRACT: Background: The clinical sequelae of intraoperative adverse events (iAEs) remain largely unknown. We sought to study the independent impact of iAEs on 30-day postoperative outcomes in abdominal surgery. Methods: The 2007-2012 institutional ACS-NSQIP and administrative databases for abdominal surgeries were matched then screened for iAEs using the ICD-9-CM-based Patient Safety Indicator “Accidental Puncture/Laceration”. A review of flagged charts was performed to confirm occurrence of iAEs. Univariate then multivariable logistic regression models were constructed to assess the independent impact of iAEs on 30-day mortality and morbidity, controlling for preoperative/intraoperative variables (e.g. age; co-morbidities; ASA; wound classification), procedure type (e.g. laparoscopic vs. open; intestinal, foregut, hepatopancreaticobiliary vs. abdominal wall procedure) and complexity (e.g. adhesions; relative value units [RVUs]). Results: 9288 cases were included; 183 had iAEs. Most injuries were addressed intraoperatively (92%) with 31% requiring tissue/organ resection and/or significant impact on/incompletion of the procedure; 8% were initially missed and required re-operation. In multivariable analyses, iAEs were independently associated with increased 30-day mortality [OR=3.19, 95% CI:1.52–6.71,p=0.002] and morbidity [OR=2.68(1.89–3.81),p<0.001], including increased risk of deep/organ-space surgical site infection [OR=1.94(1.20–3.14),p=0.007], sepsis [OR=2.14(1.32-3.47),p=0.002], pneumonia [OR=2.18(1.11–4.26),p=0.023], failure to wean off the ventilator>48 hours [OR=3.88(2.17–6.95),p<0.001], and prolonged postoperative LOS (?7 days) [OR=1.85(1.27–2.70),p=0.001] (Figure 1). Conclusions: iAEs, even when recognized and repaired intraoperatively, were independently associated with increased postoperative mortality, LOS, and a wide range of postoperative morbidities.
    No preview · Conference Paper · Dec 2015
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    Full-text · Article · Nov 2015 · Critical care medicine
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    Full-text · Article · Nov 2015 · Critical care medicine
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    ABSTRACT: Background: Gangrenous cholecystitis (GC) is difficult to diagnose preoperatively in the patient with suspected acute cholecystitis. We sought to characterize preoperative risk factors and post-operative complications. Methods: Pathology reports of all patients undergoing cholecystectomy for suspected acute cholecystitis from June 2010 to January 2014 and admitted through the emergency department were examined. Patients with GC were compared with those with acute/chronic cholecystitis (AC/CC). Data collected included demographics, preoperative signs and symptoms, radiologic studies, operative details, and clinical outcomes. Results: Thirty-eight cases of GC were identified and compared with 171 cases of AC/CC. Compared with AC/CC, GC patients were more likely to be older (57 years vs. 41 years, p < 0.001), of male sex (63% vs. 31%, p < 0.001), hypertensive (47% vs. 22%, p = 0.002), hyperlipidemic (29% vs. 14%, p = 0.026), and diabetic (24% vs. 8%, p = 0.006). GC patients were more likely to have a fever (29% vs. 12%, p = 0.007) and less likely to have nausea/vomiting (61% vs. 80%, p = 0.019) or an impacted gallstone on ultrasound (US) (8% vs. 26%, p = 0.017). Otherwise, there was no significant difference in clinical or US findings. Among GC patients, US findings were absent (8%, n = 3) or minimal (42%, n = 16). Median time from emergency department registration to US (3.3 hours vs. 2.8 hours, p = 0.28) was similar, but US to operation was longer (41.2 hours vs. 18.4 hours, p < 0.001), conversion to open cholecystectomy was more common (37% vs. 10%, p < 0.001), and hospital stay was longer (median, 4 days vs. 2 days, p < 0.0001). Delay in surgical consultation occurred in 16% of GC patients compared with 1% of AC patients (p < 0.001). Conclusion: Demographic features may be predictive of GC. Absent or minimal US signs occur in 50%, and delay in surgical consultation is common. Postoperative morbidity is greater for patients with GC compared with those with AC/CC. Level of evidence: Epidemiologic study, level III; therapeutic study, level IV.
    No preview · Article · Oct 2015
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    ABSTRACT: Background: Percutaneous drainage is the standard treatment for perforated appendicitis with abscess. We studied factors associated with complete resolution (CR) with percutaneous drainage alone. Methods: Ninety-eight patients underwent percutaneous drainage for acute appendicitis complicated by abscess (October 1990 to September 2010). CR was defined as clinical recovery, resolution of the abscess on imaging, and drain removal without recurrence. Patients achieving CR were compared with patients not achieving CR. Results: The rate of CR was 78.6% (n = 77). Abscess grade was the only radiological factor associated with CR (P = .007). The CR rate was higher with transgluteal drainage (90.9% vs 79.2%) than with other anatomic approaches (P = .018) and higher with computed tomography-guided drainage than with ultrasound-guided drainage (82.7% vs 64.3%, P = .046). Conclusion: CR was more likely to be achieved in patients with lower abscess grade, computed tomography-guided drainage, and a transgluteal approach.
    No preview · Article · Oct 2015 · American journal of surgery
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    ABSTRACT: Introduction: Distinguishing necrotizing from non-necrotizing soft tissue infections on the basis of clinical findings is challenging. None of the imaging modalities has been accepted as a gold standard for diagnosis. Our early experience has shown that IV contrast enhanced computed tomography (CT) can be very accurate in the diagnosis of necrotizing soft tissue infections (NSTI). In this study we explore the value of CT for NSTI over 5 years in our institution. Methods: We retrospectively identified patients admitted to the Massachusetts General Hospital between July 1, 2009 and July 30, 2014, who received a CT for any of the following diagnoses: necrotizing fasciitis; NSTI; cellulitis; soft tissue abscess. Based on our prior findings,1 CT was considered positive for NSTI if: a) gas was identified in the soft tissues, b) multiple fluid collections were found (as opposed to a single collection, which was more consistent of pyomyositis), c) tissues were not enhanced by IV contrast, indicating necrosis, d) there were significant inflammatory changes under the fascia. The outcome measure was NSTI defined by the visual inspection of infected and necrotic soft tissue during surgical exploration. NSTI was considered absent if surgical exploration failed to identify any of these findings or the patient was successfully treated without surgical exploration. Results: Of 150 patients that met study inclusion criteria, 51 underwent surgical exploration, and NSTI was confirmed in 14 (9%). The remaining 136 patients had either non-necrotizing infections during surgical exploration (n=37) or were treated non-operatively with successful resolution of their symptoms (n=99). The sensitivity of CT to identify NSTI was 86%, the specificity was 98%, the positive predictive value was 80%, and the negative predictive value was 99%. There were 3 patients with a positive CT result that did not have NSTI; they had either pyomyositis or a significant amount of pus that needed an operative management either way. Conclusion: CT can reliably rule out NSTI. In the presence of a negative CT, the patient can be managed non-operatively under the assumption that there are no necrotizing elements in the infected soft tissues.
    No preview · Conference Paper · Oct 2015

  • No preview · Article · Oct 2015
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    ABSTRACT: Background: Little is known about intraoperative adverse events (iAEs) in emergency surgery (ES). We sought to describe iAEs in ES and to investigate their clinical and financial impact. Methods: The 2007 to 2012 administrative and American College of Surgeons-National Surgical Quality Improvement Program databases at our tertiary academic center were: (1) linked, (2) queried for all ES procedures, and then (3) screened for iAEs using the ICD-9-CM-based Patient Safety Indicator "accidental puncture/laceration". Flagged cases were systematically reviewed to: (1) confirm or exclude the occurrence of iAEs (defined as inadvertent injuries during the operation) and (2) extract additional variables such as procedure type, approach, complexity (measured by relative value units), need for adhesiolysis, and extent of repair. Univariate and multivariate analyses were performed to assess the independent impact of iAEs on 30-day morbidity, mortality, and hospital charges. Results: Of a total of 9,288 patients, 1,284 (13.8%) patients underwent ES, of which 23 had iAEs (1.8%); 18 of 23 (78.3%) of the iAEs involved the small bowel or spleen, 10 of 23 (43.5%) required suture repair, and 8 of 23 (34.8%) required tissue or organ resection. Compared with those without iAEs, patients with iAEs were older (median age 62 vs 50; P = .04); their procedures were more complex (total relative value unit 46.7, interquartile range [27.5 to 52.6] vs 14.5 [.5 to 30.2]; P < .001), longer in duration (>3 hours: 52% vs 8%; P < .001), and more often required adhesiolysis (39.1% vs 13.5% P = .001). Patients with iAEs had increased total charges ($31,080 vs $11,330, P < .001), direct charges ($20,030 vs $7,387, P < .001), and indirect charges ($11,460 vs $4,088, P < .001). On multivariable analyses, iAEs were independently associated with increased 30-day morbidity (odds ratio, 3.56 [CI, 1.10 to 11.54]; P = .03) and prolonged postoperative length of stay (LOS; LOS >7 days; odds ratio, 5.60 [1.54 to 20.35]; P = .01]. A trend toward increased mortality did not reach statistical significance. Conclusions: In ES, iAEs are independently associated with significantly higher postoperative morbidity and prolonged LOS.
    No preview · Article · Oct 2015 · American journal of surgery
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    ABSTRACT: Background: Ultrasound (US) is the first-line diagnostic study for evaluating gallstone disease and is considered the test of choice for diagnosing acute cholecystitis (AC). However, computed tomography (CT) is used widely for the evaluation of abdominal pain and is often obtained as a first abdominal imaging test, particularly in cases in which typical clinical signs of AC are absent or other possible diagnoses are being considered. We hypothesized that CT is more sensitive than US for diagnosing AC. Methods: A prospective registry of all urgent cholecystectomies performed by our acute care surgery service between June 2008 and January 2014 was searched for cases of AC. The final diagnosis was based on operative findings and pathology. Patients were classified into two groups according to pre-operative radiographic work-up: US only or CT and US. The US group was compared with the CT and US group with respect to clinical and demographic characteristics. For patients undergoing both tests the sensitivity of the two tests was compared. Results: One hundred one patients with AC underwent both US and CT. Computed tomography was more sensitive than US for the diagnosis of AC (92% versus 79%, p = 0.015). Ultrasound was more sensitive than CT for identification of cholelithiasis (87% versus 60%, p < 0.01). Patients undergoing both tests prior to surgery were more likely to be older, male, have medical comorbidities, and lack typical clinical signs of AC. Conclusions: Computed tomography is more sensitive than US for the diagnosis of AC and is most often used in patients without typical clinical signs of AC.
    No preview · Article · Sep 2015 · Surgical Infections
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    ABSTRACT: In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.
    Full-text · Article · Aug 2015 · World Journal of Emergency Surgery
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    ABSTRACT: The value of additional imaging in clearing the cervical spine (C-spine) of alert trauma patients with tenderness on clinical exam and a negative computed tomographic (CT) scan is still unclear. All adult trauma patients with a Glasgow Coma Scale of 15, C-spine tenderness in the absence of neurologic signs, and a negative C-spine CT were included. The study period extended from September 2011 to June 2012. C-spine CT scans were interpreted in detail and considered negative in the absence of any findings indicating bony, ligamentous, or soft tissue injury around the C-spine. The incidence of C-spine injury was evaluated using early (<24 h) repeat physical examination, MRI, and/or flexion-extension films. Of 2015 patients with a C-spine CT, 383 (19 %) fulfilled the inclusion criteria. The median age was 43 (IQR: 30-53) and 44.7 % were female. Thirty-six patients (9.4 %) underwent MRI (3.7 %), flexion-extension imaging (5.2 %), or both (0.5 %), with no significant injuries identified and subsequent removal of the collar allowed. The remaining patients were clinically cleared within 24 h of presentation. None of the patients developed neurological signs following removal of the collar. On bivariate analysis, no variable except for evaluation by trauma surgery was associated with performance of additional imaging. C-spine precautions can be withdrawn without additional imaging in most blunt trauma patients with C-spine tenderness but negative neurologic evaluation and C-spine CT. Focus should be placed on the detailed and comprehensive interpretation of the C-spine CT.
    No preview · Article · Aug 2015 · World Journal of Surgery
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    ABSTRACT: Patient instability and limited radiology staffing may compel surgeons to make clinical decisions based on their independent interpretations of imaging studies. Despite potential implications for patients, no research to date has assessed the need for a diagnostic radiology curriculum in general surgery residency. We performed a cross-sectional study of surgery faculty and residents at 13 teaching hospitals across the United States. Survey responses were summarized using frequency and percentage, and analyzed by chi-square, Mantel-Haenszel chi-square, and McNemar tests. Surveys were distributed to 465 faculty and 520 residents, with response rates of 26% and 30%, respectively. Most respondents reported making decisions based on their independent imaging interpretation at least sometimes, with higher frequency in acute scenarios. The majority voiced a need for a dedicated radiology curriculum, with teaching in chest x-rays, abdominal x-rays, abdominal computed tomography, chest computed tomography, and focused assessment with sonography in trauma examinations. Surgeons and surgical residents enact treatment plans based on their independent interpretation of imaging studies, especially during acute patient scenarios. Further curricular development efforts are warranted to ensure trainee accuracy in radiologic interpretation. Copyright © 2015 Elsevier Inc. All rights reserved.
    No preview · Article · Aug 2015 · American journal of surgery
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    ABSTRACT: Translation of evidence to practice regarding adherence to published guidelines for transfusion of red blood cells (RBCs) in critically ill patients is sometimes suboptimal. We sought to use a multimodal intervention founded on peer-to-peer feedback and monthly audit to increase adherence to restrictive RBC transfusion guidelines. We conducted a prospective interventional study with a preintervention and postintervention comparison in our tertiary care center. For the 6-month preintervention period (January 1, 2013, to June 31, 2013) and the 6-month postintervention period (October 1, 2013, to March 31, 2014), all RBCs transfused in the surgical intensive care unit (SICU) were evaluated for pretransfusion hemoglobin (Hgb) trigger (TRIG). During the intervention, if stable low-risk patients were transfused outside of restrictive guidelines, the clinicians received e-mail notification and education from a surgeon colleague within 72 hours of transfusion. The mean TRIG, percentage of transfusions with TRIG greater than 8.0 g/dL, and rate of overtransfusion (posttransfusion Hgb > 10) were compared before and after intervention. For stable, low-risk patients, mean TRIG decreased from 7.6 g/dL to 7.1 g/dL (p < 0.001) and percentage of transfusions with TRIG greater than 8.0 g/dL decreased from 25% to 2% (p < 0.001) The overtransfusion rate decreased from 11%to 3% (p = 0.001). Total 6-month transfusions decreased from 284 U to 181 U, a 36% decrease. There were no significant differences in median SICU or hospital lengths of stay. Although SICU discharge Hgb and hospital discharge Hgb were significantly lower in the intervention period (8.4 vs. 8.6 [p = 0.037] and 8.6 vs. 9.0 [p = 0.003]), 30-day readmission and mortality rates were similar. A blood management program based on peer e-mail feedback was effective in improving adherence to guideline recommendations for transfusion of RBCs in stable, low-risk SICU patients. Therapeutic/care management study, level IV.
    No preview · Article · Jul 2015
  • George C Velmahos

    No preview · Article · Jun 2015 · JAMA SURGERY
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    ABSTRACT: Enteral nutrition (EN) delivery in the surgical intensive care unit (ICU) is often suboptimal as it is commonly interrupted for procedures. We hypothesized that continuing perioperative nutrition or providing compensatory nutrition would improve caloric delivery without increasing morbidity. We enrolled 10 adult surgical ICU patients receiving EN who were scheduled for elective bedside percutaneous tracheostomy. In these patients (fed group), either perioperative EN was maintained or compensatory nutrition was provided. We compared the amount of calories delivered, caloric deficits, and the rate of complications of these patients with those of 22 contemporary controls undergoing tracheostomy while adhering to the traditional American Society of Anesthesiology nil per os guidelines (unfed group). We defined caloric deficit as the difference between prescribed calories and actual delivered calories. There was no difference in demographic characteristics between the two groups. On the day of procedure, the fed group had higher median delivered calories (1706 kcal; interquartile range [IQR], 1481-2009 versus 588 kcal; IQR, 353-943; P < 0.0001) and received a higher percentage of prescribed calories (92%; IQR, 82%-97% versus 34%; IQR, 24%-51%; P < 0.0001). Median caloric deficit on the day of the procedure was significantly lower in the fed group (175 kcal; IQR, 49-340 versus 1133 kcal; IQR, 660-1365; P < 0.0001). There were no differences in total overall ICU complications per patient, gastrointestinal complications on the day of procedure, or total infectious complications per patient between the two groups. In our pilot study, perioperative and compensatory nutrition resulted in higher caloric delivery and was not associated with increased morbidity. Copyright © 2015 Elsevier Inc. All rights reserved.
    Full-text · Article · Jun 2015 · Journal of Surgical Research
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    ABSTRACT: On April 15, 2013, two improvised explosive devices (IEDs) exploded at the Boston Marathon and 264 patients were treated at 26 hospitals in the aftermath. Despite the extent of injuries sustained by victims, there was no subsequent mortality for those treated in hospitals. Leadership decisions and actions in major trauma centers were a critical factor in this response. The objective of this investigation was to describe and characterize organizational dynamics and leadership themes immediately after the bombings by utilizing a novel structured sequential qualitative approach consisting of a focus group followed by subsequent detailed interviews and combined expert analysis. Across physician leaders representing 7 hospitals, several leadership and management themes emerged from our analysis: communications and volunteer surges, flexibility, the challenge of technology, and command versus collaboration. Disasters provide a distinctive context in which to study the robustness and resilience of response systems. Therefore, in the aftermath of a large-scale crisis, every effort should be invested in forming a coalition and collecting critical lessons so they can be shared and incorporated into best practices and preparations. Novel communication strategies, flexible leadership structures, and improved information systems will be necessary to reduce morbidity and mortality during future events. (Disaster Med Public Health Preparedness. 2015;0:1-7).
    Full-text · Article · Jun 2015 · Disaster Medicine and Public Health Preparedness
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    ABSTRACT: Graduated Drivers Licensing (GDL) programs phase in driving privileges for teenagers. In 2007, Massachusetts implemented a stricter version of the 1998 GDL law, with increased fines and education. This study evaluated the impact of the law on motor vehicle crash (MVC)-related health care utilization and charges. Massachusetts government and US Census Bureau data were analyzed to compare the rates of MVC-related emergency department (ED) visits and hospital charges before (2002-2006) and after (2007-2011) the 2007 GDL law. Three driver age groups were studied: 16-17 (evaluating the law effect), 18-20 (evaluating the sustainability of the effect), and 25-29 years old (control group). MVC-related ED visits per population decreased after the law for all three age groups (16-17: 2326 to 713; 18-20: 2110 to 1304; 25-29: 1694 to 1228; per 100,000, p<0.001), but the decrease was greater amongst teenagers (16-17: -69%; 18-20: -38%) compared to the control group (-27%); p<0.001. MVC-related hospital charges per population also decreased for teenagers but increased for the control group (16-17: $2.70m to $1.45m; 18-20: $3.52m to $2.26m; 25-29: $1.86m to $1.92m; per 100,000, p<0.001). The 2007 GDL law in Massachusetts was associated with significant decreases in MVC-related health care utilization and hospital charges among teenage drivers. Copyright © 2015. Published by Elsevier Inc.
    No preview · Article · Jun 2015 · Journal of Pediatric Surgery
  • Haytham M A Kaafarani · George C Velmahos

    No preview · Article · Jun 2015 · World Journal of Surgery
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    ABSTRACT: Fulminant Clostridium difficile colitis (fCDC) is a highly lethal disease with mortality rates ranging between 12% and 80%. Although often these patients require a total abdominal colectomy (TAC) with ileostomy, there is no established management protocol for post-operative antibiotics. In this study we aim to make some recommendations for post-operative antibiotic usage, while describing the practice across different institutions. Multi-institutional retrospective case series including fCDC patients who underwent a TAC between January 1, 2007, and June 30, 2012. We first analyzed the complete cohort and consecutively performed a survivor analysis, comparing different antibiotic regimens. Additionally we stratified by time interval (antibiotics for ≤7 d, or ≥8 d). Primary outcome was in-hospital mortality. Additional secondary outcomes included hospital length of stay (HLOS), ICU LOS, number of ventilator-free days, and occurrence of intra-abdominal complications (proctitis, abscess, sepsis, etc.). A total of 100 fCDC patients that underwent a TAC were included across five institutions. Four different antibiotic regimens were compared; A (metronidazole IV+vancomycin PO), B (metronidazole IV), C (metronidazole IV+vanco PO and PR), and D (metronidazole IV+vancomycin PR). The combination of IV metronidazole with or without PO vancomycin showed superior outcomes in terms of a shorter ICU length of stay and more ventilator-free days. However, when comparing metronidazole alone vs. metronidazole and any combination of vancomycin, no significant differences were found. Neither the addition of vancomycin enema, nor the time interval changed outcomes. Patients, after a TAC for fCDC, may be placed on either IV metronidazole or PO vancomycin depending upon local antibiograms, and proctitis may be treated with the addition of a vancomycin enema (PR). There was no data to support routine treatment of more than 7 d.
    No preview · Article · Jun 2015 · Surgical Infections

Publication Stats

13k Citations
1,606.98 Total Impact Points

Institutions

  • 2006-2015
    • Harvard Medical School
      • Department of Surgery
      Boston, Massachusetts, United States
  • 2005-2015
    • Massachusetts General Hospital
      • • Department of Surgery
      • • Division of Trauma, Emergency Surgery and Surgical Critical Care
      Boston, Massachusetts, United States
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2013
    • Boston University
      Boston, Massachusetts, United States
  • 2012
    • University of Massachusetts Medical School
      • Department of Surgery
      Worcester, Massachusetts, United States
  • 2007
    • Keck School of Medicine USC
      Los Ángeles, California, United States
  • 1996-2007
    • University of California, Los Angeles
      • Department of Surgery
      Los Ángeles, California, United States
  • 1994-2006
    • University of Southern California
      • Department of Surgery
      Los Ángeles, California, United States
  • 2004
    • Oregon Health and Science University
      • Department of Surgery
      Portland, OR, United States
  • 2002
    • University of California, San Francisco
      • Department of Surgery
      San Francisco, California, United States
    • University of Vermont
      • Department of Surgery
      Burlington, Vermont, United States
    • California State University, Sacramento
      Sacramento, California, United States
  • 1999
    • Santa Barbara Cottage Hospital
      Santa Barbara, California, United States
  • 1998-1999
    • City University Los Angeles
      Los Ángeles, California, United States
  • 1994-1997
    • University of the Witwatersrand
      • Department of Surgery
      Johannesburg, Gauteng, South Africa
  • 1994-1996
    • Chris Hani Baragwanath Hospital
      Johannesburg, Gauteng, South Africa
  • 1993
    • University of Johannesburg
      Johannesburg, Gauteng, South Africa