Papers by Christiaan Hoff
ANZ Journal of Surgery, 2007
Neoadjuvant therapy is given before surgery to improve resectability, local control and/or surviv... more Neoadjuvant therapy is given before surgery to improve resectability, local control and/or survival. Post-operative radiation therapy for locally advanced rectal cancer has been long accepted, and since 1990 adding fluorouracil (5FU) chemotherapy became the NIH standard. However, trials then showed that pre-operative radiotherapy followed by surgery improved local control over surgery alone, but had a less consistent effect on overall survival. The German trial (Sauer, NEJM, 2004, 351:1731) showed a 5 year local relapse rate of 6% for pre-operative chemo-radiotherapy and 13% for post-operative chemo-radiotherapy for T3 or T4 or node-positive rectal cancer treated by TME. The EORTC 22921 trial (37% had TME) showed a similar reduction in local recurrence whether 5FU/leucovorin chemotherapy was given with pre-operative radiotherapy, after pre-operative radiotherapy plus surgery, or both (Bosset, NEJM, 2006, 355:1114. Trials show increased rates of complete pathological remission, increased acute toxicity, but no consistent effects on sphincter preservation rates or overall survival when chemotherapy is combined with pre-operative radiation.
Early Learning Effect of Residents for Laparoscopic Sigmoid Resection
Journal of Surgical Education, 2013
To evaluate the effect of learning the laparoscopic sigmoid resection procedure on resident surge... more To evaluate the effect of learning the laparoscopic sigmoid resection procedure on resident surgeons; establish a minimum number of cases before a resident surgeon could be expected to achieve proficiency with the procedure; and examine if an analysis could be used to measure and support the clinical evaluation of the surgeon's competence with the procedure. Retrospective analysis of data which was prospective entered in the database. From 2003 to 2007 all patients who underwent a laparoscopic sigmoid resection carried out by senior residents, who completed the procedure as the primary surgeon proctored by an experienced surgeon, were included in the study. A cumulative sum control chart (CUSUM) analysis was used evaluate performance. The procedure was defined as a failure if major intra-operative complications occurred such as intra abdominal organ injury, bleeding, or anastomotic leakage; if an inadequate number of lymph nodes (<12 nodes) were removed; or if conversion to an open surgical procedure was required. Thirteen residents performed 169 laparoscopic sigmoid resections in the period evaluated. A significant majority of the resident surgeons were able to consistently perform the procedure without failure after 11 cases and determined to be competent. One resident was not determined to be competent and the CUSUM score supported these findings. We concluded that at least 11 cases are required for most residents to obtain necessary competence with the laparoscopic sigmoid resection procedure. Evaluation with the CUSUM analysis can be used to measure and support the clinical evaluation of the resident surgeon's competence with the procedure.
Surgical Endoscopy, 2014
Background Several different procedures have been proposed as a revisional procedure for treatmen... more Background Several different procedures have been proposed as a revisional procedure for treatment of failed laparoscopic adjustable gastric banding (LAGB). Laparoscopic Roux-en-Y gastric bypass (LRYGB) has been advocated as the procedure of choice for revision. In this study, we compare the single-and two-step approaches for the revision of failed LAGB to LRYGB. Method All patients who underwent bariatric surgery were included in a prospective database. For the purpose of this study, patients who underwent revisional surgery from LAGB to LRYGB were selected. Records for individual patients were completed by data review. Complication rates and weight development were recorded until 2 years postoperatively. Data were compared between both procedures and with complications rates reported in literature. Results Revisional gastric bypass surgery was performed in 257 patients. This was done as a planned single-step procedure in 220 (86 %) patients without indications for acute band removal and in 32 patients as a planned 2 step procedure. Five patients were planned as a single-step procedure but were intraoperatively converted to a 2-step procedure based on poor pouch tissue quality. No postoperative mortality occurred in both groups. No differences in early major morbidity and stricture formation were seen between the two groups. Gastric ulceration was more frequently observed after 2-steps procedure (8.5 vs. 1.7 %, p \ 0.05). In comparison with data reported in literature, the single-step procedure had similar to lower complication rates. Percentage excess weight loss two years after revisional gastric bypass procedure was, respectively, 53 versus 67 % (p = 0.147) for single-and two-step procedure. Conclusion In patients without indications for acute band removal, the planned conversion of gastric banding to Roux-Y gastric bypass can be safely done in a single-step procedure without increase in morbidity and no difference in postoperative weight loss.
International Journal of Colorectal Disease, 2011
Purpose A steep learning curve exists for surgeons to become skilled in laparoscopic colon resect... more Purpose A steep learning curve exists for surgeons to become skilled in laparoscopic colon resection. Our institute offers a proctored training programme. The purpose of this descriptive study was to evaluate whether the course resulted in adoption of laparoscopic colorectal surgery into clinical practice, explore post-course practice patterns and analyse the outcome of surgical performance. Methods Between 2003 and 2008, 26 surgeons were trained by our institute. The course consisted of 24 elective laparoscopic resections under direct supervision. A questionnaire and a prospective post-course web-based registration were used to analyse the effect of the training and the outcome of surgical performance.
Diseases of the Colon & Rectum, 2007
P urpose: The aim of the present study was to investigate how the Quality of Life of patients wit... more P urpose: The aim of the present study was to investigate how the Quality of Life of patients with rectal cancer changes over time after laparoscopic Total Mesorectal Excision. Methods: Patients completed the Medical Outcomes Study Short Form 36, and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire and a colorectal specific European Organisation for Research and Treatment of Cancer quality of life questionnaire before laparoscopic Total Mesorectal Excision, on discharge from hospital and at 3, 6 and 12 months postoperatively. Patients were treated by laparoscopic low anterior resection or laparoscopic abdominoperineal resection. Results: Fifty-one patients (mean age: 64 years, 29 (57 percent) male) participated in this study, of whom 38 (75 percent) underwent laparoscopic low anterior resection and 13 (25 percent) laparoscopic abdominoperineal resection. Compared with preoperative scores on the Medical Outcomes Study Short Form 36, patients reported a deterioration in physical functioning (74 vs. 80, p=0.009), and improved mental functioning (76 vs. 70, p=0.007) at 3 months. Improvement in emotional wellbeing was reported both on the Medical Outcomes Study Short Form 36 (78 vs. 53, p=0.006) and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (84 vs. 69, p<0.001). At one year, improvements in global Qualify of Life (82 vs. 68, p=0.001) and symptoms like fatigue (18 vs. 32, p<0.001), pain (5 vs. 12, p=0.009) and appetite loss (3 vs. 13, p=0.01) were reported. However, sexual functioning was worse from 3 months onward until one year after surgery (47 vs. 66, p=0.004). Patients who underwent low anterior resection experienced less sexual dysfunction than patients after abdominoperineal resection (21 vs. 56, p=0.004). Conclusion: One year after laparoscopic Total Mesorectal Excision for rectal cancer, patients reported improvement in some important Quality of Life outcomes, including global Quality of Life, despite a decrease in sexual functioning. 96 Chapter 6
Surgical Endoscopy, 2011
Background The transition from basic skills training in a skills lab to procedure training in the... more Background The transition from basic skills training in a skills lab to procedure training in the operating theater using the traditional master-apprentice model (MAM) lacks uniformity and efficiency. When the supervising surgeon performs parts of a procedure, training opportunities are lost. To minimize this intervention by the supervisor and maximize the actual operating time for the trainee, we created a new training method called INtraoperative Video-Enhanced Surgical Training (INVEST). Methods Ten surgical residents were trained in laparoscopic cholecystectomy either by the MAM or with INVEST. Each trainee performed six cholecystectomies that were objectively evaluated on an Objective Structured Assessment of Technical Skills (OSATS) global rating scale. Absolute and relative improvements during the training curriculum were compared between the groups. A questionnaire evaluated the trainee's opinion on this new training method. Results Skill improvement on the OSATS global rating scale was significantly greater for the trainees in the INVEST curriculum compared to the MAM, with mean absolute improvement 32.6 versus 14.0 points and mean relative improvement 59.1 versus 34.6% (P = 0.02). Conclusion INVEST significantly enhances technical and procedural skill development during the early learning curve for laparoscopic cholecystectomy. Trainees were positive about the content and the idea of the curriculum. Keywords Training Á Minimally invasive surgery Á Video Á INVEST Á Operating theater Á Cholecystectomy Laparoscopic surgery requires complex techniques and skills that are not employed in open surgery. The instruments provide limited haptic feedback, lack degrees of freedom, and move inverted inside the abdomen [1, 2].
Interoperative efficiency in minimally invasive surgery suites
Surgical Endoscopy, 2009
Performing minimally invasive surgery (MIS) in a conventional operating room (OR) requires additi... more Performing minimally invasive surgery (MIS) in a conventional operating room (OR) requires additional specialized equipment otherwise stored outside the OR. Before the procedure, the OR team must collect, prepare, and connect the equipment, then take it away afterward. These extra tasks pose a thread to OR efficiency and may lengthen turnover times. The dedicated MIS suite has permanently installed laparoscopic equipment that is operational on demand. This study presents two experiments that quantify the superior efficiency of the MIS suite in the interoperative period. Preoperative setup and postoperative breakdown times in the conventional OR and the MIS suite in an experimental setting and in daily practice were analyzed. In the experimental setting, randomly chosen OR teams simulated the setup and breakdown for a standard laparoscopic cholecystectomy (LC) and a complex laparoscopic sigmoid resection (LS). In the clinical setting, the interoperative period for 66 LCs randomly assigned to the conventional OR or the MIS suite were analyzed. In the experimental setting, the setup and breakdown times were significantly shorter in the MIS suite. The difference between the two types of OR increased for the complex procedure: 2:41 min for the LC (p &lt; 0.001) and 10:47 min for the LS (p &lt; 0.001). In the clinical setting, the setup and breakdown times as a whole were not reduced in the MIS suite. Laparoscopic setup and breakdown times were significantly shorter in the MIS suite (mean difference, 5:39 min; p &lt; 0.001). Efficiency during the interoperative period is significantly improved in the MIS suite. The OR nurses&#39; tasks are relieved, which may reduce mental and physical workload and improve job satisfaction and patient safety. Due to simultaneous tasks of other disciplines, an overall turnover time reduction could not be achieved.
Surgical Endoscopy, 2005
B ackground: Next to surgical margins, yield of lymph nodes, and length of bowel resected, macros... more B ackground: Next to surgical margins, yield of lymph nodes, and length of bowel resected, macroscopic completeness of mesorectal excision may serve as another quality control of total mesorectal excision (TME). In this study, the macroscopic completeness of laparoscopic TME was evaluated. Methods: A series of 25 patients with rectal cancer were managed laparoscopically (LTME) and included in this study. The pathologic specimens of the LTME group were prospectively examined and matched with a historical group of resection specimens from patients who had undergone open TME (OTME). The two groups were matched for gender and type of resection (low anterior or abdominoperineal resection). Special care was given to the macroscopic judgment concerning the completeness of the mesorectum. Results: A three-grade scoring system showed no differences between the LTME and OTME groups. Conclusion: The current study supports the hypothesis that oncologic resection using laparoscopic TME is feasible and adequate.
Optimal ergonomics for laparoscopic surgery in minimally invasive surgery suites: a review and guidelines
Surgical Endoscopy, 2009
With minimally invasive surgery (MIS), a man-machine environment was brought into the operating r... more With minimally invasive surgery (MIS), a man-machine environment was brought into the operating room, which created mental and physical challenges for the operating team. The science of ergonomics analyzes these challenges and formulates guidelines for creating a work environment that is safe and comfortable for its operators while effectiveness and efficiency of the process are maintained. This review aimed to formulate the ergonomic challenges related to monitor positioning in MIS. Background and guidelines are formulated for optimal ergonomic monitor positioning within the possibilities of the modern MIS suite, using multiple monitors suspended from the ceiling. All evidence-based experimental ergonomic studies conducted in the fields of laparoscopic surgery and applied ergonomics for other professions working with a display were identified by PubMed searches and selected for quality and applicability. Data from ergonomic studies were evaluated in terms of effectiveness and efficiency as well as comfort and safety aspects. Recommendations for individual monitor positioning are formulated to create a personal balance between these two ergonomic aspects. Misalignment in the eye-hand-target axis because of limited freedom in monitor positioning is recognized as an important ergonomic drawback during MIS. Realignment of the eye-hand-target axis improves personal values of comfort and safety as well as procedural values of effectiveness and efficiency. Monitor position is an important ergonomic factor during MIS. In the horizontal plain, the monitor should be straight in front of each person and aligned with the forearm-instrument motor axis to avoid axial rotation of the spine. In the sagittal plain, the monitor should be positioned lower than eye level to avoid neck extension.
Validity and Reliability of Global Operative Assessment of Laparoscopic Skills (GOALS) in Novice Trainees Performing a Laparoscopic Cholecystectomy
Journal of surgical education, Jan 16, 2014
Global Operative Assessment of Laparoscopic Skills (GOALS) assessment has been designed to evalua... more Global Operative Assessment of Laparoscopic Skills (GOALS) assessment has been designed to evaluate skills in laparoscopic surgery. A longitudinal blinded study of randomized video fragments was conducted to estimate the validity and reliability of GOALS in novice trainees. In total, 10 trainees each performed 6 consecutive laparoscopic cholecystectomies. Sixty procedures were recorded on video. Video fragments of (1) opening of the peritoneum; (2) dissection of Calot's triangle and achievement of critical view of safety; and (3) dissection of the gallbladder from the liver bed were blinded, randomized, and rated by 2 consultant surgeons using GOALS. Also, a grade was given for overall competence. The correlation of GOALS with live observation Objective Structured Assessment of Technical Skills (OSATS) scores was calculated. Construct validity was estimated using the Friedman 2-way analysis of variance by ranks and the Wilcoxon signed-rank test. The interrater reliability was ca...
CR18P Laparoscopic vs Open Total Mesorectal Excision for Rectal Cancer: An Evaluation of the Mesorectum?S Macroscopic Quality
ANZ Journal of Surgery, 2007
Surgical Endoscopy, 2008
Background With the expanding implementation of minimally invasive surgery, the operating team is... more Background With the expanding implementation of minimally invasive surgery, the operating team is confronted with challenges in the field of ergonomics. Visual feedback is derived from a monitor placed outside the operating field. This crossover trial was conducted to evaluate and compare neck posture in relation to monitor position in a dedicated minimally invasive surgery (MIS) suite and a conventional operating room. Methods Assessment of the neck was conducted for 16 surgeons, assisting surgeons, and scrub nurses performing a laparoscopic cholecystectomy in both types of operating room. Flexion and rotation of the cervical spine were measured intraoperatively using a video analysis system. A two-question visual analog scale (VAS) questionnaire was used to evaluate posture in relation to the monitor position. Results Neck rotation was significantly reduced in the MIS suite for the surgeon (p = 0.018) and the assisting surgeon (p \ 0.001). Neck flexion was significantly improved in the MIS suite for the surgeon (p \ 0.001) and the scrub nurse (p = 0.018). On the questionnaire, the operating room team scored their posture significantly higher in the MIS suite and also indicated fewer musculoskeletal complaints.
Laparoscopic versus Open Total Mesorectal Excision A Comparative Study on Short-Term Outcomes
Digestive Surgery, 2007
Laparoscopic total mesorectal excision (TME) is being used in rectal cancer more frequently. The ... more Laparoscopic total mesorectal excision (TME) is being used in rectal cancer more frequently. The aim of this study was to analyze the differences in short-term outcomes between open and laparoscopic TME. In this nonrandomized consecutive study, the short-term outcomes of 100 patients undergoing TME for proven rectal cancer were analyzed. Two groups of 50 patients underwent an open or laparoscopic TME for rectal cancer. Both groups were comparable. Laparoscopic surgery took longer to perform (250 vs. 197.5 min, p &amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01), but was accompanied by less blood loss (350 vs. 800 ml, p &amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Enteric function recovered sooner after laparoscopy. The numbers of major and minor complications were comparable between both groups, although fewer patients had major complications in the laparoscopic group (6 vs. 15 patients, p = 0.03). Hospital stay was shorter for patients who underwent a laparoscopic abdominoperineal resection (10 vs. 12 days, p = 0.04). Median follow-up was 17 months for the laparoscopic group and 22 months for the open group. Survival analyses between the groups showed no statistical difference in disease-free and overall survival. This study shows that laparoscopic TME for rectal cancer is a safe and feasible technique with some short-term benefits over open TME.
Effective and efficient learning in the operating theater with intraoperative video-enhanced surgical procedure training
Surgical Endoscopy, 2013
INtraoperative Video Enhanced Surgical procedure Training (INVEST) is a new training method desig... more INtraoperative Video Enhanced Surgical procedure Training (INVEST) is a new training method designed to improve the transition from basic skills training in a skills lab to procedural training in the operating theater. Traditionally, the master-apprentice model (MAM) is used for procedural training in the operating theater, but this model lacks uniformity and efficiency at the beginning of the learning curve. This study was designed to investigate the effectiveness and efficiency of INVEST compared to MAM. Ten surgical residents with no laparoscopic experience were recruited for a laparoscopic cholecystectomy training curriculum either by the MAM or with INVEST. After a uniform course in basic laparoscopic skills, each trainee performed six cholecystectomies that were digitally recorded. For 14 steps of the procedure, an observer who was blinded for the type of training determined whether the step was performed entirely by the trainee (2 points), partially by the trainee (1 point), or by the supervisor (0 points). Time measurements revealed the total procedure time and the amount of effective procedure time during which the trainee acted as the operating surgeon. Results were compared between both groups. Trainees in the INVEST group were awarded statistically significant more points (115.8 vs. 70.2; p &lt; 0.001) and performed more steps without the interference of the supervisor (46.6 vs. 18.8; p &lt; 0.001). Total procedure time was not lengthened by INVEST, and the part performed by trainees was significantly larger (69.9 vs. 54.1 %; p = 0.004). INVEST enhances effectiveness and training efficiency for procedural training inside the operating theater without compromising operating theater time efficiency.
Assessment of Clinical Complete Response After Chemoradiation for Rectal Cancer with Digital Rectal Examination, Endoscopy, and MRI: Selection for Organ-Saving Treatment
Annals of Surgical Oncology, 2015
The response to chemoradiotherapy (CRT) for rectal cancer can be assessed by clinical examination... more The response to chemoradiotherapy (CRT) for rectal cancer can be assessed by clinical examination, consisting of digital rectal examination (DRE) and endoscopy, and by MRI. A high accuracy is required to select complete response (CR) for organ-preserving treatment. The aim of this study was to evaluate the value of clinical examination (endoscopy with or without biopsy and DRE), T2W-MRI, and diffusion-weighted MRI (DWI) for the detection of CR after CRT. This prospective cohort study in a university hospital recruited 50 patients who underwent clinical assessment (DRE, endoscopy with or without biopsy), T2W-MRI, and DWI at 6-8 weeks after CRT. Confidence levels were used to score the likelihood of CR. The reference standard was histopathology or recurrence-free interval of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;12 months in cases of wait-and-see approaches. Diagnostic performance was calculated by area under the receiver operator characteristics curve, with corresponding sensitivities and specificities. Strategies were assessed and compared by use of likelihood ratios. Seventeen (34 %) of 50 patients had a CR. Areas under the curve were 0.88 (0.78-1.00) for clinical assessment and 0.79 (0.66-0.92) for T2W-MRI and DWI. Combining the modalities led to a posttest probability for predicting a CR of 98 %. Conversely, when all modalities indicated residual tumor, 15 % of patients still experienced CR. Clinical assessment after CRT is the single most accurate modality for identification of CR after CRT. Addition of MRI with DWI further improves the diagnostic performance, and the combination can be recommended as the optimal strategy for a safe and accurate selection of CR after CRT.
Journal of Behavioral Medicine, 2011
Based on attribution theory, this study hypthesized that past spousal supportiveness may act as a... more Based on attribution theory, this study hypthesized that past spousal supportiveness may act as a moderator of the link between one partner's current support behavior and the other partner's relationship satisfaction. A sample of 88 patients with colorectal cancer and their partners completed questionnaires approximately 3 and 9 months after diagnosis. The data were analyzed employing dyadic data analytic approaches. In the short-term, spousal active engagement-which involved discussing feelings and engaging in joint problem solving-was positively associated with relationship satisfaction in patients as well as in partners, but only when past spousal support was relatively low. Spousal protective buffering-which involved hiding worries and fears and avoiding talking about the disease-was negatively associated with relationship satisfaction in patients, again only when past spousal support was relatively low. If past spousal support was high, participants rated the quality of their relationship relatively high, regardless of their partner's current support behavior. Over time, past spousal supportiveness was not found to mitigate the negative association between spousal protective buffering and relationship satisfaction. Overall, our results indicate that relationship satisfaction can be maintained if past spousal supportiveness is high even if the partner is currently not very responsive to the individual's needs, at least in the short-term.
International Journal of Colorectal Disease, 2010
Purpose Some authors state that elective laparoscopic recto-sigmoid resection is more difficult f... more Purpose Some authors state that elective laparoscopic recto-sigmoid resection is more difficult for diverticular disease as compared with malignancy. For this reason, starting laparoscopic surgeons might avoid diverticulitis, making the implementation phase unnecessary long. The aim of this study was to determine whether laparoscopic resection for diverticular disease should be included during the implementation phase. Methods All consecutive patients who underwent an elective laparoscopic recto-sigmoid resection in our hospital for diverticulitis or cancer from 2003 to 2007 were analysed. Results A total of 256 consecutive patients were included in this prospective cohort study. One hundred and fifty-one patients were operated on for diverticulitis and 105 for cancer. There was no significant difference in operation time (168 vs. 172 min), blood loss (189 vs. 208 ml), conversion rates (9.9% vs. 11.4%), hospital stay (8 vs. 8 days), total number of peroperative (2.3% vs.
International journal of colorectal disease, 2011
A steep learning curve exists for surgeons to become skilled in laparoscopic colon resection. Our... more A steep learning curve exists for surgeons to become skilled in laparoscopic colon resection. Our institute offers a proctored training programme. The purpose of this descriptive study was to evaluate whether the course resulted in adoption of laparoscopic colorectal surgery into clinical practice, explore post-course practice patterns and analyse the outcome of surgical performance. Between 2003 and 2008, 26 surgeons were trained by our institute. The course consisted of 24 elective laparoscopic resections under direct supervision. A questionnaire and a prospective post-course web-based registration were used to analyse the effect of the training and the outcome of surgical performance. The response rate of the questionnaire was 85%. The majority had not performed any laparoscopic colon resections before attending the course. All 24 respondents successfully implemented laparoscopy into daily practice. After the course, 70% of all sigmoid resections were performed laparoscopically i...
BMC Surgery, 2014
Background: Primary perineal wound closure after conventional abdominoperineal resection (cAPR) f... more Background: Primary perineal wound closure after conventional abdominoperineal resection (cAPR) for rectal cancer has been the standard of care for many years. Since the introduction of neo-adjuvant radiotherapy and the extralevator APR (eAPR), oncological outcome has been improved, but at the cost of increased rates of perineal wound healing problems and perineal hernia. This has progressively increased the use of biological meshes, although not supported by sufficient evidence. The aim of this study is to determine the effectiveness of pelvic floor reconstruction using a biological mesh after standardized eAPR with neo-adjuvant (chemo)radiotherapy compared to primary perineal wound closure.
International Journal of Colorectal Disease, 2011
Purpose A steep learning curve exists for surgeons to become skilled in laparoscopic colon resec... more Purpose A steep learning curve exists for surgeons to become skilled in laparoscopic colon resection. Our institute offers a proctored training programme. The purpose of this descriptive study was to evaluate whether the course resulted in adoption of laparoscopic colorectal surgery into clinical practice, explore post-course practice patterns and analyse the outcome of surgical performance. Methods Between 2003 and 2008, 26 surgeons
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Papers by Christiaan Hoff