Dara O Kavanagh

Royal College of Surgeons in Ireland, Dublin, Leinster, Ireland

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Publications (17)60.84 Total impact

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    ABSTRACT: Within surgery, several specialties demand advanced technical skills, specifically in the minimally invasive environment. Two groups of 10 medical students were recruited on the basis of their aptitude (visual-spatial ability, depth perception, and psychomotor ability). All subjects were tested consecutively using the ProMIS III simulator until they reached proficiency performing laparoscopic suturing. Simulator metrics, critical error scores, observed structured assessment of technical skills scores, and Fundamentals of Laparoscopic Surgery scores were recorded. Group A (high aptitude) achieved proficiency after a mean of 7 attempts (range, 4-10). In group B (low aptitude), 30% achieved proficiency after a mean of 14 attempts (range, 10-16). In group B, 40% demonstrated improvement but did not attain proficiency, and 30% failed to progress. Distinct learning curves for laparoscopic suturing can be mapped on the basis of fundamental ability. High aptitude is directly related to earlier completion of the learning curve. A proportion of subjects with low aptitude are unable to reach proficiency despite repeated attempts.
    American journal of surgery 02/2014; 207(2):263-70. · 2.36 Impact Factor
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    ABSTRACT: Simulated surgical training offers a safe and accessible way of learning surgical procedures outside the operating room. Training programs have been developed using simulated laboratories to train surgical trainees to proficiency outside the operating room. Despite the global enthusiasm among educators to enhance training through simulation-based learning, it remains to be elucidated whether the skill set obtained is transferrable to the operating room. Using standardized search methods, the authors searched the Cochrane Central Register of Controlled Trials, PubMed, Embase, and Web-Based Knowledge, as well as the reference lists of relevant articles, and retrieved all published randomized controlled trials. Sixteen randomized controlled trials involving 309 participants were identified to be suitable for qualitative analysis using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The mean Consolidated Standards of Reporting Trials score was 16 (range, 12-22). The studies showed considerable clinical and methodologic diversity. Operative time improved consistently in all trials after training and was the only objective parameter measurable in the live setting. Studies that used the Objective Structured Assessment of Technical Skills as their primary outcome showed improved scores in 80% of trials, and studies that used performance indicators to assess participants all showed improved scores after simulation training in all of the trials, with 88% showing statistical significance. The current literature consistently demonstrates the positive impact of simulation on operative time and predefined performance scores. However, these reproducible measures alone are insufficient to demonstrate transferability of skills from the laboratory to the operating room. The authors advocate a multimodal assessment, including metrics, the Objective Structured Assessment of Technical Skills, and critical step completion. This may provide a more complete assessment of operative performance. Only then can it be concluded that simulation skills are transferable to the live operative setting.
    American journal of surgery 10/2013; · 2.36 Impact Factor
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    ABSTRACT: The attainment of technical competence for surgical procedures is fundamental to a proficiency-based surgical training program. We hypothesized that aptitude may directly affect one's ability to successfully complete the learning curve for minimally invasive procedures. The aim was to assess whether aptitude has an impact on ability to achieve proficiency in completing a simulated minimally invasive surgical procedure. The index procedure chosen was a laparoscopic appendectomy. Two groups of medical students with disparate aptitude were selected. Aptitude (visual-spatial, depth perception, and psychomotor ability) was measured by previously validated tests. Indicators of technical proficiency for laparoscopic appendectomy were established by trained surgeons with an individual case volume of more than 150. All subjects were tested consecutively on the ProMIS III (Haptica) until they reached predefined proficiency in this procedure. Simulator metrics, critical error scores, and Objective Structured Assessment of Technical Skills (OSATS) scores were recorded. The mean numbers of attempts to achieve proficiency in performing a laparoscopic appendectomy for group A (high aptitude) and B (low aptitude) were 6 (range 4 to 7) and 14 (range 10 to 18), respectively (p < 0.0001). Significant differences were found between the 2 groups for path length (p = 0.014), error score (p = 0.021), and OSATS score (p < 0.0001) at the initial attempt. High aptitude is directly related to a rapid attainment of proficiency. These findings suggest that resource allocation for proficiency-based technical training in surgery may need to be tailored according to a trainee's natural ability.
    Journal of the American College of Surgeons 09/2013; · 4.50 Impact Factor
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    World Journal of Surgery 03/2012; · 2.23 Impact Factor
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    ABSTRACT: Improved preoperative localizing studies have facilitated minimally invasive approaches in the treatment of primary hyperparathyroidism (PHPT). Success depends on the ability to reliably select patients who have PHPT due to single-gland disease. We propose a model encompassing preoperative clinical, biochemical, and imaging studies to predict a patient's suitability for minimally invasive surgery. For the purposes of the present study, 180 consecutive patients were included for analysis. A 5-variable model based on preoperative ionized serum calcium (>1.4 mmol/l), intact parathyroid hormone level (≥ 2 times the upper limit of normal), positive sestamibi scan for a single affected gland, positive ultrasound scan for a single gland, and concordance between the two imaging modalities for single-gland disease at a similar location was employed, where a score of 1 was allocated for each variable present. Of the 180 patients, 62 (34%) underwent bilateral exploration, 63 (36%) underwent unilateral exploration, and 55 (30%) underwent minimally invasive parathyroidectomy. The results showed that 92% had single-gland disease, 3% had double adenomas, and 5% had hyperplasia. Biochemical cure was achieved in 98.9%. Mean follow-up was 153 days (range: 80-342 days). With the predictive scoring model, a score of ≥ 3 had a positive predictive value of 100% for single-gland disease. A scoring model encompassing preoperative biochemical and imaging data can be successfully employed to predict suitability for minimally invasive surgery in the majority of patients with single-gland disease.
    World Journal of Surgery 12/2011; 36(5):1175-81. · 2.23 Impact Factor
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    ABSTRACT: Laparoscopic resection of low rectal cancer poses significant technical difficulties for the surgeon. There is a lack of published follow-up data in relation to the surgical, oncological and survival outcomes in these patients. The aim of this study is to evaluate the surgical, oncological and survival outcomes in all patients undergoing laparoscopic resection for low rectal cancer. Consecutive patients undergoing laparoscopic resection for low rectal cancers were included in the study. Clinical, pathological and follow-up data were recorded over a 4-year period. The mean follow-up was 25 months A total of 53 patients were included in the study, 30 of whom were males. The mean age was 64.14 years (range, 34-86 years). The mean hospital stay was 8.2 days (range, 4-42 days). Fifty were completed laparoscopically and three were converted to an open procedure. Thirty-eight were anterior resections and 15 were abdominoperineal resections. Twenty-four patients received neoadjuvant chemoradiotherapy. The total mesorectal excision was optimal in 51 (98%) cases. There were no anastomotic sequelae and no surgical mortality. There was no local recurrence detected. The overall survival (mean follow-up, 25 months) was 93.5%. Laparoscopic resection for low rectal cancers permits optimum oncological control. In our series, this technical approach is associated with excellent 4-year survival and clinical outcomes.
    International Journal of Colorectal Disease 05/2011; 26(9):1143-9. · 2.24 Impact Factor
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    ABSTRACT: Laparoscopic inguinal hernia repair has emerged as a viable alternative to the open procedure. To date, few studies have included validated measures of quality of life as end points. We compared quality-of-life outcomes following laparoscopic versus open repair of inguinal hernia. All laparoscopic repairs were performed via the totally extraperitoneal route (TEP). All open procedures were Lichtenstein repairs (LR). Hernia repairs performed between January 1999 and December 2006 were included in the study. Data was recorded prospectively and each TEP repair was matched with a LR for analysis. The SF-36 form was used to assess quality of life. Statistical significance was determined using the two-sample Wilcoxon rank-sum (Mann-Whitney) test. Three hundred fourteen procedures were performed during the study period, 164 (52%) had a TEP repair and 150 (48%) had a LR. Ninety TEP repairs were matched with 90 LR. Recurrence rates were 3% following TEP repair and 2% following LR. There was a significant difference between the laparoscopic and open groups in terms of physical function (p = 0.0001), physical role (p < 0.0001), bodily pain (p = 0.0029), general health (p = 0.0025), and emotional role (p < 0.0001). There was no significant difference between the groups in terms of vitality (p = 0.2501), mental health (p = 0.08), or social functioning (p = 0.1677). These data suggest that the TEP repair results in less postoperative pain, a quicker return to normal functional status, and improved quality-of-life outcomes with equivalent recurrence rates when compared to the LR.
    World Journal of Surgery 12/2010; 34(12):3059-64. · 2.23 Impact Factor
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    ABSTRACT: Laparoscopic resection for colon cancer has been proven to have a similar oncological efficacy compared to open resection. Despite this, it is performed by a minority of colorectal surgeons. The aim of our study was to evaluate the short-term clinical, oncological and survival outcomes in all patients undergoing laparoscopic resection for colon cancer. From July 2005 to December 2008, 202 consecutive patients underwent laparoscopic resection for colon cancer. Surgery was analysed on an intention to treat basis. The mean follow-up was 24.3 months. Two hundred twenty-two patients underwent resection for colon cancer. Two hundred two underwent laparoscopic resection (91%). One hundred sixteen were male patients. Mean age was 65.9 years (range = 24-91). The median length of stay was 6.6 days (mean = 7.1 days). One hundred eighty-eight of 202 (93.1%) were completed laparoscopically. Fourteen (6.9%) were converted. The overall morbidity rate was 15.8%. There were three clinically apparent anastomotic leaks. The 30-day mortality was 1 (0.5%). The mean nodal yield was 13.4 (range = 8-37) nodes. There were no positive margins detected. Overall survival in laparoscopically treated colon cancer was 88.1%. In those patients with non-metastatic disease, the overall survival was 90.7% (165/182). Laparoscopic resection for colon cancer is achievable in 85% (188/222) of patients. This facilitates adequate oncological clearance. It is associated with a low morbidity rate and favourable short-term survival outcomes. This data reflects the potential outcomes dedicated MIS colorectal units will have to offer colon cancer patients once laparoscopic colorectal surgery becomes the de facto surgical approach.
    International Journal of Colorectal Disease 10/2010; 26(3):361-8. · 2.24 Impact Factor
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    ABSTRACT: Epidemiological, clinical, and molecular studies suggest a role for oestrogen in thyroid cancer. How oestrogen mediates its effects and the consequence of it on clinical outcome has not been fully elucidated. The participation of coregulatory proteins in modulating oestrogen receptor (ER) function and input of crosstalk with the tyrosine kinase receptor HER2 was investigated. Oestrogen induced cell proliferation in the follicular thyroid cancer (FTC)-133 cells, but not in the anaplastic 8305C cell line. Knockdown of the coactivator steroid receptor coactivator (SRC)-1 inhibited FTC-133 basal, but not oestrogen induced, cell proliferation. Oestrogen also increased protein expression of SRC-1 and the ER target gene cyclin D1 in the FTC-133 cell line. ERalpha, ERbeta, the coregulatory proteins SRC-1 and nuclear corepressor (NCoR), and the tyrosine kinase receptor HER2 were localised by immunohistochemistry and immnofluorescence in paraffin-embedded tissue from thyroid tumour patients (n=111). ERalpha was colocalised with both SRC-1 and NCoR to the nuclei of the tumour epithelial cells. Expression of ERalpha and NCoR was found predominantly in non-anaplastic tumours and was significantly associated with well-differentiated tumours and reduced incidence of disease recurrence. In non-anaplastic tumours, HER2 was significantly associated with SRC-1, and these proteins were associated with poorly differentiated tumours, capsular invasion and disease recurrence. Totally, 87% of anaplastic tumours were positive for SRC-1. Kaplan-Meier estimates of disease-free survival indicated that in thyroid cancer, SRC-1 strongly correlates with reduced disease-free survival (P<0.001), whereas NCoR predicted increased survival (P<0.001). These data suggest opposing roles for the coregulators SRC-1 and NCoR in thyroid tumour progression.
    Endocrine Related Cancer 03/2010; 17(1):255-64. · 5.26 Impact Factor
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    ABSTRACT: Enhanced recovery programmes (ERPs) have demonstrated reduced morbidity and length of hospital stay in patients undergoing open elective colorectal resections. The application of laparoscopic techniques to colorectal surgery is associated with shorter length of stay and morbidity compared to open resections. In the setting of laparoscopic surgery, it is unclear whether there is an additive effect on length of stay and morbidity by combining these. The current study addresses the benefit of an ERP (RAPID protocol) in a cohort of matched patients undergoing laparoscopic sigmoid colon resection Consecutive patients over a 40-month period who underwent laparoscopic sigmoid colon resection were assigned either to the RAPID protocol (group 1) or traditional post operative care (group 2) in a non-randomised manner. Analysis was on an "intention to treat" basis. Primary and secondary endpoints were identified; primary endpoints included length of hospital stay and readmission rate. Secondary endpoints included morbidity and mortality rate. Seventy-three consecutive patients were included. Group 1 included 37 patients. Group 2 included 36 patients. Median length of hospital stay in groups 1 and 2 was 5 and 8 days, respectively (p = 0.01). Readmission rate in groups 1 and 2 was 8.1% and 8.3%, respectively (p = 0.98). Morbidity rate in groups 1 and 2 was 30% and 22%, respectively (p = 0.61); there was one mortality in each group. The application of the ERP (RAPID) to patients undergoing laparoscopic sigmoid colon resection results in a significant improvement in length of hospital stay, with comparable morbidity and readmission rates.
    International Journal of Colorectal Disease 02/2010; 25(6):761-6. · 2.24 Impact Factor
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    ABSTRACT: The occurrence of intussusception in adults is rare. The condition is found in 1 in 1300 abdominal operations and 1 in 100 patients operated for intestinal obstruction. The child to adult ratio is 20:1. A 52-year-old Irish Caucasian woman was investigated for a 3-month history of intermittent episodes of colicky midgut pain and associated constipation. Ileocolonoscopy revealed a pedunculated lesion in the terminal ileum prolapsing into the caecum. Computed tomography confirmed a smooth-walled, nonobstructing, low density intramural lesion in the terminal ileum with secondary intussusception. A laparoscopic small bowel resection was performed. Histology revealed a large pedunculated polypoidal mass measuring 4 x 2.5 x 2 cm consistent with a submucosal lipoma. She had complete resolution of her symptoms and remained well at 12-month follow-up. This case highlights an unusual cause of incomplete small bowel obstruction successfully treated through interdisciplinary cooperation. Ileal lipomas are not typically amenable to endoscopic removal and require resection. This can be successfully achieved via a laparoscopic approach with early restoration of premorbid functioning.
    Journal of Medical Case Reports 02/2010; 4:51.
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    ABSTRACT: A 67-year-old Caucasian male was referred by the urology service with a history of incomplete bowel emptying. He complained of tenesmus. MRI scan suggested a leiomyoma lying anterior to the rectum. He underwent examination under anaesthesia and attempted endorectal ultrasound and biopsy. However, the lesion seemed to migrate cranially and was impalpable. At laparoscopy, a mobile, unattached, 5.5 × 5 × 3.5, cream-coloured 'egg was retrieved from the retrovesical space. Histology confirmed a hyalinised fibrocollagenous lesion lined with mesothelium. A comprehensive review of the literature is presented.
    Case Reports in Medicine 01/2010; 2010.
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    ABSTRACT: Impairments of speech and language are important consequences of head injury as they compromise interaction between the patient and others. A large spectrum of communication deficits can occur. There are few reports in the literature of aphasia following closed head injury despite the common presentation of closed head injury. Herein we report two cases of closed head injuries with differing forms of aphasia. We discuss their management and rehabilitation and present a detailed literature review on the topic. In a busy acute surgical unit one can dismiss aphasia following head injury as behaviour related to intoxication. Early recognition with prolonged and intensive speech and language rehabilitation therapy yields a favourable outcome as highlighted in our experience. These may serve as a reference for clinicians faced with this unusual outcome.
    Case Reports in Medicine 01/2010; 2010:678060.
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    Stephen Ryan, Dara O Kavanagh, Paul C Neary
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    ABSTRACT: Perineal hernias are infrequent complications following abdominoperineal operations. Various approaches have been described for repair of perineal hernias including open transabdominal, transperineal or combined abdominoperineal repairs. The use of laparoscopic transabdominal repair of perineal hernias is not well-described. We present a case report demonstrating the benefits of laparoscopic repair of perineal hernia following previous laparoscopic abdominoperineal resection (APR) using a nonabsorbable mesh to repair the defect. We have demonstrated that the use of laparoscopy with repair of the pelvic floor defect using a non absorbable synthetic mesh offers an excellent alternative with many potential advantages over open transabdominal and transperineal repairs.
    Case Reports in Medicine 01/2010; 2010.
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    ABSTRACT: The development of novel chemotherapeutic agents in colorectal cancer has improved survival. Following initial response to chemotherapeutic strategies many patients develop refractory disease. This poses a significant challenge common to many cancer subtypes. Newer agents such as Bevacizumab have successfully targeted the tyrosine kinase receptor epidermal growth factor receptor in metastatic colorectal cancer. Human epidermal growth factor receptor-2 is another member of the tyrosine kinase receptor family which has been successfully targeted in breast cancer. This may play a role in colorectal cancer. We conducted a clinicopathological study to determine if overexpression of human epidermal growth factor receptor-2 is a predictor of outcome in a cohort of patients with colorectal cancer. Clinicopathological data and paraffin-embedded specimens were collected on 132 consecutive patients who underwent colorectal resections over a 24-month period at Mayo General Hospital. Twenty-six contained non-malignant disease. Her-2/neu protein overexpression was detected using immunohistochemistry (IHC). The HER-2 4B5 Ventana monoclonal antibody was used. Fluorescent insitu hybridisation (FISH) was performed using INFORM HER-2/Neu Plus. Results were correlated with established clinical and pathological predictors of outcome including TNM stage. Statistical analysis was performed using SPSS version 11.5. 114 were HER-2/Neu negative using IHC, 7 showed barely perceptible positivity (1+), 9 showed moderate staining (2+) and 2 were strongly positive (3+). There was no correlation with gender, age, grade, Dukes' stage, TNM stage, time to recurrence and 5-year survival (p > 0.05). FISH was applied to all 2+ and 3+ cases as well as some negative cases selected at random. Three were amplified (2 were 3+ and 1 was 2+). Similarly, HER-2 gene overexpression did not correlate with established prognostic indicators. HER-2 protein is over expressed in 11% of colorectal cancer patients. The gene encoding HER-2 is amplified in 3% of cases. Overexpression of HER-2 is not a predictor of outcome. However, patients who over express HER-2 may respond to Herceptin therapy.
    BMC Cancer 02/2009; 9:1. · 3.33 Impact Factor
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    ABSTRACT: The role of oestrogen in oncogenesis has been examined extensively, especially in the context of breast cancer, and receptor modulators are an integral part of targeted treatment in this disease. The role of oestrogen signalling in colonic carcinoma is poorly understood. Men are more susceptible than women to colon cancer. Furthermore, hormone-replacement therapy affords an additive protective effect for postmenopausal women, and when these women do develop cancer, they typically have less aggressive disease. The discovery of a second oestrogen receptor (ERbeta) and its over expression in healthy human colon coupled with reduced expression in colon cancer suggests that this receptor might be involved. The underlying mechanism, however, remains largely unknown. In this Review, we discuss the various hypotheses presented in the published literature. We examine the cellular and molecular mechanisms through which oestrogen is purported to exert its protective influence, and we review the evidence available to support these claims.
    The Lancet Oncology 05/2008; 9(4):385-91. · 25.12 Impact Factor
  • Journal of the American College of Surgeons 11/2006; 203(4):579. · 4.50 Impact Factor

Publication Stats

95 Citations
60.84 Total Impact Points

Institutions

  • 2013–2014
    • Royal College of Surgeons in Ireland
      Dublin, Leinster, Ireland
  • 2011–2012
    • St. Vincents University Hospital
      • Department of Radiology
      Dublin, Leinster, Ireland
  • 2009–2010
    • Mayo General Hospital
      Caisleán an Bharraigh, Connaught, Ireland