A comparison of ultrasound guided bilateral single injection shot Erector Spinae Plane blocks versus wound infiltration for post-operative analgesia in laparoscopic assisted colonic surgery- a prospective randomised study.

BACKGROUND: Both wound infiltration (WI) with local anaesthetic and Erector Spinae Plane block (ESPB) have been described for post-operative analgesia after abdominal surgery. This study compared the efficacy of WI versus ESPB for post-operative analgesia after laparoscopic assisted colonic surgery. METHODS: Seventy-two patients between 18 and 85 years of age undergoing elective surgery were randomised to receive either WI or ESPB. In the WI group a 40 ml bolus of 0.5% Ropivacaine, infiltrated at the ports and minimally invasive wound at subcutaneous and fascia layers. In the ESPB group at T8 level, under ultrasound guidance, a 22-gauge nerve block needle was passed through the Erector Spinae muscle to reach its fascia. A dose up to 40 ml of 0.5% Ropivacaine, divided into two equal volumes, was injected at each side. Both groups had a multimodal analgesic regime, including regular Paracetamol, dexamethasone and patient-controlled analgesia (PCA) with Fentanyl. The primary end point was a post-operative pain score utilising a verbal Numerical Rating Score (NRS, 0-10) on rest and coughing in the post anaesthetic care unit (PACU) and in the first 24 h. Secondary outcomes measured were: opioid usage, length of stay and any clinical adverse events. RESULTS: There was no significant treatment difference in PACU NRS at rest and coughing (p-values 0. 382 and 0.595respectively). Similarly, there were no significant differences in first 24 h NRS at rest and coughing (p-values 0.285 and 0.431 respectively). There was no significant difference in Fentanyl use in PACU or in the first 24 h (p- values 0.900 and 0.783 respectively). Neither was there a significant difference found in mean total Fentanyl use between ESPB and WI groups (p-value 0.787). CONCLUSION: Our observations found both interventions had an overall similar efficacy. TRIAL REGISTRATION: The study was registered with the Australian New Zealand Clinical Trial Registry (ACTRN: 12619000113156 ).

Pravastatin for early-onset pre-eclampsia: a randomised, blinded, placebo-controlled trial.

OBJECTIVE: Women with pre-eclampsia have elevated circulating levels of soluble fms-like tyrosine kinase-1 (sFlt-1). Statins can reduce sFlt-1 from cultured cells and improve pregnancy outcome in animals with a pre-eclampsia-like syndrome. We investigated the effect of pravastatin on plasma sFlt-1 levels during pre-eclampsia. DESIGN: Blinded (clinician and participant), proof of principle, placebo-controlled trial. SETTING: Fifteen UK maternity units. POPULATION: We used a minimisation algorithm to assign 62 women with early-onset pre-eclampsia (24+0 -31+6  weeks of gestation) to receive pravastatin 40 mg daily (n = 30) or matched placebo (n = 32), from randomisation to childbirth. PRIMARY OUTCOME: Difference in mean plasma sFlt-1 levels over the first 3 days following randomisation. RESULTS: The difference in the mean maternal plasma sFlt-1 levels over the first 3 days after randomisation between the pravastatin (n = 27) and placebo (n = 29) groups was 292 pg/ml (95% CI -1175 to 592; P = 0.5), and over days 1-14 was 48 pg/ml (95% CI -1009 to 913; P = 0.9). Women who received pravastatin had a similar length of pregnancy following randomisation compared with those who received placebo (hazard ratio 0.84; 95% CI 0.50-1.40; P = 0.6). The median time from randomisation to childbirth was 9 days (interquartile range [IQR] 5-14 days) for the pravastatin group and 7 days (IQR 4-11 days) for the placebo group. There were three perinatal deaths in the placebo-treated group and no deaths or serious adverse events attributable to pravastatin. CONCLUSIONS: We found no evidence that pravastatin lowered maternal plasma sFlt-1 levels once early-onset pre-eclampsia had developed. Pravastatin appears to have no adverse perinatal effects. TWEETABLE ABSTRACT: Pravastatin does not improve maternal plasma sFlt-1 or placental growth factor levels following a diagnosis of early preterm pre-eclampsia #clinicaltrial finds.

Comparison of ultrasound-guided transmuscular quadratus lumborum block catheter technique with surgical pre-peritoneal catheter for postoperative analgesia in abdominal surgery: a randomised controlled trial.

Following abdominal surgery, the provision of postoperative analgesia with local anaesthetic infusion through both transmuscular quadratus lumborum block and pre-peritoneal catheter have been described. This study compared these two methods of postoperative analgesia following laparotomy. Eighty-two patients 18-85 years of age scheduled to undergo elective surgery were randomly allocated to receive either transmuscular quadratus lumborum block or pre-peritoneal catheter block. In the transmuscular quadratus lumborum group, an 18-gauge Tuohy needle was passed through the quadratus lumborum muscle under ultrasound guidance to reach its anterior aspect. A 20-ml bolus of ropivacaine 0.375% was administered and catheters placed bilaterally. In the pre-peritoneal catheter group, 20 ml of ropivacaine 0.375% was infiltrated at each of three subcutaneous sub-fascial levels, and pre-peritoneal plane catheters were placed bilaterally. Both groups received an infusion of ropivacaine 0.2% at 5 ml.h-1 , continued up to 48 h along with a multimodal analgesic regime that included regular paracetamol and patient-controlled analgesia with fentanyl. The primary end-point was postoperative pain score on coughing, assessed using a numerical rating score (0-10). Secondary outcomes were pain score at rest, fentanyl usage until 48 h post-operation, satisfaction scores and costs. There was no treatment difference between the two groups for pain score on coughing (p = 0.24). In the transmuscular quadratus lumborum group, there was a reduction in numerical rating score at rest (p = 0.036) and satisfaction scores on days 1 and 30 (p = 0.004, p = 0.006, respectively), but fentanyl usage was similar. In the transmuscular quadratus lumborum group, the highest and lowest blocks observed in the recovery area were T4 and L1, respectively. The transmuscular quadratus lumborum technique cost 574.64 Australian dollars more per patient than the pre-peritoneal catheter technique.

Prospective randomized trial of neoadjuvant chemotherapy during the 'wait period' following preoperative chemoradiotherapy for rectal cancer: results of the WAIT trial.

AIM: The aim was to determine whether the addition of additional cycles of chemotherapy during the 'wait period' following neoadjuvant chemoradiotherapy for rectal cancer improves the pathological complete response (pCR) rate. METHOD: Rectal cancer patients were randomly allocated either to a standard 10 week wait period before surgery (standard chemoradiotherapy, SCRT) or to receive three cycles of fluorouracil based chemotherapy following chemoradiotherapy during a similar 10 week wait (extended chemoradiotherapy, XCRT). The primary end-point was pCR as determined by blinded pathological assessment. RESULTS: Forty-nine patients were randomized (SCRTn = 24, XCRTn = 25). pCR occurred in 10 patients overall but there was no significant difference in pCR between the groups (SCRTn = 6, XCRTn = 4, P = 0.49). CONCLUSION: The addition of three cycles of 5-fluorouracil/leucovorin in a 10 week wait period after conventional chemoradiotherapy seems to result in similar pCR rates in patients with locally advanced rectal cancer based on this small randomized trial.

Non-technical skills of surgical trainees and experienced surgeons.

BACKGROUND: In addition to technical expertise, surgical competence requires effective non-technical skills to ensure patient safety and maintenance of standards. Recently the Royal Australasian College of Surgeons implemented a new Surgical Education and Training (SET) curriculum that incorporated non-technical skills considered essential for a competent surgeon. This study sought to compare the non-technical skills of experienced surgeons who completed their training before the introduction of SET with the non-technical skills of more recent trainees. METHODS: Surgical trainees and experienced surgeons undertook a simulated scenario designed to challenge their non-technical skills. Scenarios were video recorded and participants were assessed using the Non-Technical Skills for Surgeons (NOTSS) scoring system. Participants were divided into subgroups according to years of experience and their NOTSS scores were compared. RESULTS: For most NOTSS elements, mean scores increased initially, peaking around the time of Fellowship, before decreasing roughly linearly over time. There was a significant downward trend in score with increasing years since being awarded Fellowship for six of the 12 NOTSS elements: considering options (score -0·015 units per year), implementing and reviewing decisions (-0·020 per year), establishing a shared understanding (-0·014 per year), setting and maintaining standards (-0·024 per year), supporting others (-0·031 per year) and coping with pressure (-0·015 per year). CONCLUSION: The drop in NOTSS score was unexpected and highlights that even experienced surgeons are not immune to deficiencies in non-technical skills. Consideration should be given to continuing professional development programmes focusing on non-technical skills, regardless of the level of professional experience.

Surgeons' and trainees' perceived self-efficacy in operating theatre non-technical skills.

BACKGROUND: An important factor that may influence an individual's performance is self-efficacy, a personal judgement of capability to perform a particular task successfully. This prospective study explored newly qualified surgeons' and surgical trainees' self-efficacy in non-technical skills compared with their non-technical skills performance in simulated scenarios. METHODS: Participants undertook surgical scenarios challenging non-technical skills in two simulation sessions 6 weeks apart. Some participants attended a non-technical skills workshop between sessions. Participants completed pretraining and post-training surveys about their perceived self-efficacy in non-technical skills, which were analysed and compared with their performance in surgical scenarios in two simulation sessions. Change in performance between sessions was compared with any change in participants' perceived self-efficacy. RESULTS: There were 40 participants in all, 17 of whom attended the non-technical skills workshop. There was no significant difference in participants' self-efficacy regarding non-technical skills from the pretraining to the post-training survey. However, there was a tendency for participants with the highest reported self-efficacy to adjust their score downwards after training and for participants with the lowest self-efficacy to adjust their score upwards. Although there was significant improvement in non-technical skills performance from the first to second simulation sessions, a correlation between participants' self-efficacy and performance in scenarios in any of the comparisons was not found. CONCLUSION: The results suggest that new surgeons and surgical trainees have poor insight into their non-technical skills. Although it was not possible to correlate participants' self-belief in their abilities directly with their performance in a simulation, in general they became more critical in appraisal of their abilities as a result of the intervention.

Systematic review of skills transfer after surgical simulation-based training.

BACKGROUND: Simulation-based training assumes that skills are directly transferable to the patient-based setting, but few studies have correlated simulated performance with surgical performance. METHODS: A systematic search strategy was undertaken to find studies published since the last systematic review, published in 2007. Inclusion of articles was determined using a predetermined protocol, independent assessment by two reviewers and a final consensus decision. Studies that reported on the use of surgical simulation-based training and assessed the transferability of the acquired skills to a patient-based setting were included. RESULTS: Twenty-seven randomized clinical trials and seven non-randomized comparative studies were included. Fourteen studies investigated laparoscopic procedures, 13 endoscopic procedures and seven other procedures. These studies provided strong evidence that participants who reached proficiency in simulation-based training performed better in the patient-based setting than their counterparts who did not have simulation-based training. Simulation-based training was equally as effective as patient-based training for colonoscopy, laparoscopic camera navigation and endoscopic sinus surgery in the patient-based setting. CONCLUSION: These studies strengthen the evidence that simulation-based training, as part of a structured programme and incorporating predetermined proficiency levels, results in skills transfer to the operative setting.

Effect of preoperative two-dimensional animation information on perioperative anxiety and knowledge retention in patients undergoing bowel surgery: a randomized pilot study.

AIM: The use of multimedia information provided preoperatively can potentially reduce anxiety in patients and improve the hospital experience. However, the use of two-dimensional (2D) animation (cartoon) to provide information to patients undergoing colorectal surgery has not been investigated. This study investigated the effect of preoperative 2D information on anxiety and knowledge retention in patients undergoing bowel surgery. METHOD: Patients were randomized to one of two groups; the video group watched a 13-min cartoon animation whereas the nonvideo group did not. Anxiety levels were measured at the preadmission clinic, postvideo, on the day of admission for surgery, within 24-h after surgery and before discharge using the Spielberger state-trait anxiety inventory and visual analogue scale. Both groups completed a knowledge retention questionnaire and the video group completed a feedback questionnaire about the animation. RESULTS: Thirty-one patients (16 video, 15 nonvideo) participated in the study. There was no significant difference in baseline anxiety score between two groups. An immediate reduction (P = 0.03) in anxiety score was observed in the video group after watching the video compared with baseline. There was a significant reduction in anxiety score in the video group at discharge compared with the nonvideo group (P = 0.03). There was no significant difference in knowledge retention between two groups. Eighty-eight per cent of patients who watched the video found it beneficial. CONCLUSION: 2D animation is an effective medium for delivering information to patients undergoing bowel surgery and can potentially reduce anxiety related to surgery and improve the hospital experience.

The nursing and financial implications of laparoscopic colorectal surgery: data from a randomized controlled trial.

AIM: The issue of cost effectiveness of laparoscopic surgery remains uncertain and its impact on the ward nursing staff is unaddressed. This study investigated these issues using patients from a single centre admitted to a randomized controlled trial. METHOD: All patients recruited into the Australasian Laparoscopic Colon Cancer Study (ALCCaS) from The Queen Elizabeth Hospital between January 1999 and March 2005 were included in this study. Data relating to hospital cost were collated from the Hospital Patient Costing System. Nursing interventions were calculated in minutes per patient, using the excelcare Software database. RESULTS: Data from 97 patients were analysed (laparoscopy, 53; open surgery, 44). The median number of hours of nursing input per patient was 80 (27.5-907) h in the open surgery group and 58.5 (15-684.5) h in the laparoscopy group. This difference was further increased after exclusion of patients converted from laparoscopy to open surgery. The median total cost of the procedure was AUS $9698/£ 5631 (AUS $3862-90,397) in the open surgery group and AUS $10,951/£ 6219 (AUS$2337-66,237) in the laparoscopy group. CONCLUSION: These data suggest that laparoscopic colorectal surgery is equivalent in price to open surgery and there may be added benefits in reduced nursing intensity.

Australasian Laparoscopic Colon Cancer Study shows that elderly patients may benefit from lower postoperative complication rates following laparoscopic versus open resection.

BACKGROUND: A retrospective analysis of age-related postoperative morbidity in the Australia and New Zealand prospective randomized controlled trial comparing laparoscopic and open resection for right- and left-sided colonic cancer is presented. METHODS: A total of 592 eligible patients were entered and studied from 1998 to 2005. RESULTS: Data from 294 patients who underwent laparoscopic and 298 who had open colonic resection were analysed; 266 patients were aged less than 70 years and 326 were 70 years or older (mean(s.d.) 70.3(11.0) years). Forty-three laparoscopic operations (14.6 per cent) were converted to an open procedure. Fewer complications were reported for intention-to-treat laparoscopic resections compared with open procedures (P = 0.002), owing primarily to a lower rate in patients aged 70 years or more (P = 0.002). Fewer patients in the laparoscopic group experienced any complication (P = 0.035), especially patients aged 70 years or above (P = 0.019). CONCLUSION: Treatment choices for colonic cancer depend principally upon disease-free survival; however, patients aged 70 years or over should have rigorous preoperative investigation to avoid conversion and should be considered for laparoscopic colonic resection. REGISTRATION NUMBER: NCT00202111 (http://www.clinicaltrials.gov).

Management and survival trends in advanced colorectal cancer.

AIMS: Significant improvements in the outcome for patients with advanced colorectal cancer (CRC) have been achieved. The median survival for advanced CRC reported in clinical trials now approaches 2 years, but there is often a question as to whether this partly represents patient selection. We aimed to explore whether the availability of new chemotherapy drugs (irinotecan and oxaliplatin) and surgical advances have affected survival in a normal clinical setting. MATERIALS AND METHODS: A review of the Queen Elizabeth and Lyell McEwin health service prospective CRC database from 1992 to 2004 was carried out to assess outcome differences between two time cohorts (1 January 1992-31 December 1997 and 1 January 1998-31 December 2004). RESULTS: For all patients (n = 744) overall survival was seen to improve over time and is maintained out to 5 years. There have been a number of trends over time (1992-1997 vs 1998-2004) that have probably contributed to this gain; increased overall chemotherapy use (33% vs 43%); use of combination chemotherapy (i.e. oxaliplatin and irinotecan regimens); increased hepatic resection rates (1.9% vs 10.8%) and increased clinical trial uptake (0.6% vs 14.5%). CONCLUSION: This current analysis confirms an improvement in survival over time for advanced CRC and this is seen in unselected patients including those over 70 years of age.

Laparoscopically assisted colectomy: a study of risk factors and predictors of open conversion.

BACKGROUND: Conversion to an open procedure during laparoscopically assisted colorectal resection may be necessary because of technical, patient, or pathologic factors. Recent literature has indicated that converted patients may have poorer outcomes than those undergoing open or completed laparoscopically assisted procedure. This study aimed to audit the authors' experience with laparoscopically assisted colectomy and to assess the clinical outcomes of patients undergoing conversion. METHODS: All laparoscopic right hemicolectomies or anterior resections performed at seven South Australian hospitals from 1997 to 2006 were reviewed. Data pertaining to patient sex, age, American Society of Anesthesiology (ASA) score, pathology, operative outcomes including operating time, conversion, reason for conversion, length of hospital stay, and intra- and postoperative complications were analyzed. RESULTS: Laparoscopic anterior resection had a higher rate of open conversion than laparoscopic right hemicolectomy (18.7% vs 10.4%; p = 0.028). In the right hemicolectomy group, none of the investigated risk factors for conversion were statistically significant, and the morbidity rates for the two groups were similar. The median hospital stay was significantly longer in the anterior resection group (p < 0.001), and the wound morbidity rate was higher in the converted group (12.8% vs 3.0%; p = 0.022). Age older than 75 years and a high ASA status were independent risk factors for conversion in anterior resection. CONCLUSIONS: Conversion of laparoscopic anterior resection to open procedure is associated with higher wound morbidity and a longer hospital stay. The authors recommend that surgeons carefully consider the selection of patients 75 years of age or older and high ASA status for laparoscopic anterior resection.

Consistency in the reporting of sexual behaviour by adolescent girls in Kenya: a comparison of interviewing methods.

OBJECTIVES: To investigate in a district in Kenya the level and consistency of reporting of sexual behaviour among adolescent girls randomly assigned to two modes of survey interview: face to face interview and audio computer assisted self-interview (ACASI). METHODS: The analysis is based on a subsample of over 700 never married girls aged 15-21 years in Kisumu, Kenya, drawn from a population based survey of over 2100 respondents. A questionnaire with 69 questions was used, two thirds of which were considered sensitive, including questions about risky sexual behaviour, alcohol and drug use, contraceptive practice, pregnancy, induced abortions, and births. RESULTS: ACASI produced significantly higher reporting of sex with a relative, stranger, or older man, and higher reporting of coerced sex. However, differences by mode for ever had sex and sex with a boyfriend were not significant. Relative to ACASI, the interviewer administered mode produced highly consistent reporting of sexual activity, both within the main interview and between the main and exit interviews. CONCLUSIONS: Both the mode of survey administration and the probing for various behaviours significantly affect the observed prevalence of sexual activity. The ACASI results suggest that adolescent girls in Kenya have more complex and perilous sex lives than traditional face to face surveys of sexual activity indicate. The level of consistency in the interviewer mode is argued to be suspect, particularly given the much lower levels of reporting, relative to ACASI, for types of sexual partners and coerced sexual activity.

Dipeptidase 1: a candidate tumor-specific molecular marker in colorectal carcinoma.

The aim of this study was to identify tumor-specific markers for the detection of rare disseminated colorectal tumor cells in peripheral venous blood and in intra-peritoneal saline lavage samples collected before and after resection of colorectal tumors. Using cDNA micro-array screening, we found dipeptidase 1 (DPEP1) to be highly expressed in colon tumors compared to matched normal mucosa. Relative reverse transcriptase (RT)-PCR showed that DPEP1 was over-expressed by >/=2 fold in colon tumor compared to normal colonic mucosal tissue in 56/68 (82%) patients. Using immunobead RT-PCR, a technique that first enriches for epithelial cells, we found DPEP1 positive cells in intra-peritoneal lavage and venous blood samples from 15/38 (39%) colorectal cancer cases. This is the first report of DPEP1 as a marker for disseminated colon tumor cells.

Parastomal hernia repair.

OBJECTIVE: The aim of this study was to audit the results of parastomal hernia repair. METHODS: A retrospective review was made of all patients having parastomal hernia repair at 2 teaching hospitals over a 12-year period. RESULTS: Forty-three patients had 51 parastomal hernia repairs. Three types of hernia repair were used: 14 (28%) local suture, 19 (37%) local mesh repair and 18 (35%) stoma relocation. Three patients died and significant complications occurred in 65% of repairs. Parastomal hernia recurred in 18 (38%) of repairs. This was greatest with a sutured repair (59%) and least in patients having stoma relocation (24%). Repair with mesh was associated with a 39% recurrence rate. No significant statistical difference was found for the results of these repairs. CONCLUSION: Parastomal hernia repair is associated with high rates of morbidity, mortality and recurrence. Repair should not be undertaken without a good indication.

Sentinel node biopsy for squamous-cell carcinoma of the anus and anal margin.

PURPOSE: The majority of anal tumors are squamous-cell carcinomas. These may be tumors of the anal canal or margin. They are best treated by combination of chemotherapy and radiotherapy. T1 and T2 tumors in this regime do not receive radiotherapy to the inguinal regions despite approximately 5 to 10 percent incidence of inguinal lymph node involvement. If the nodal status of the inguinal region could be accurately assessed, then a more tailored radiotherapy regime may be given. This article describes a novel method of assessment of the status of the inguinal lymph nodes in patients. METHODS: Patients with anal squamous-cell carcinoma had four injections of 0.2 ml of antimony sulfide (30 MBq) around the tumor. Under a gamma camera, a distant high-intensity signal was located, and this point was marked on the overlying skin using an indelible ink pen. In the operating theater, patent blue dye was injected all around the tumor. The localized lymph node was removed and sent for histopathology. RESULTS: This procedure was performed on 12 patients. The sentinel node was localized to the inguinal region and removed in eight of these patients. In two patients, metastatic squamous-cell carcinoma was identified histologically in the sentinel node. CONCLUSION: We advocate that this as a safe technique for detecting metastatic disease in the inguinal nodes in patients with anal squamous-cell carcinoma.

The effect of lavage on intraabdominal cell burden.

BACKGROUND: Abdominal lavage is a common surgical practice, but few studies have been conducted to assess its efficacy at removing cells from the abdominal cavity, particularly during laparoscopic surgery. METHODS: After three 12-mm trocars were inserted into six female 30-kg pigs at the umbilicus left and right iliac fossae, the abdomen was insufflated with carbon dioxide. The pelvis of each pigs was injected with 6 million radiolabeled LIM 1215 cells. Then the abdominal cavity was irrigated with either 500 ml 0.9% saline, 500 ml 10% betadine solution, or 1 L 0.9% saline. A maximum of 5 L of solution was used for each animal. The lavage fluid was suctioned into separate containers after each aliquot, and each container was measured for radioactivity. RESULTS: Significantly greater numbers of cells were removed by lavage by the first to third lavage cycle; however, after four lavage cycles, relatively few cells were removed by each further cycle. No difference was observed between 500-ml and 1-L aliquots. Additionally, the mechanical efficacy of 0.9% saline and 10% betadine solution appeared similar. CONCLUSION: These findings suggest that optimal lavage consists of four irrigation/suction cycles utilizing 500-ml aliquots.

Variables in the spread of tumor cells to trocars and port sites during operative laparoscopy.

BACKGROUND: Port-site recurrences have delayed the uptake of laparoscopic colectomy, but the etiology of these is incompletely understood. These studies were designed to investigate variables such as the size of the tumor inoculum and the volume and pressure of the insufflated gas during operative laparoscopy that might affect the deposition of these cells in relation to trocars and port sites. METHODS: Radiolabeled human colon cancer cells were injected into the peritoneal cavity of pigs. Three trocars were inserted, and the abdomen was insufflated with carbon dioxide. The movement of cells within the abdomen was traced on a gamma camera. After 2 h, the trocars were removed and the port sites excised. Two studies were performed. In the first study, tumor inocula were varied from 1.5 x 10(5) to 120 x 10(5). In the second study, insufflation pressure was varied, with pressures 0, 4, 8 and 12 mmHg were studied. RESULTS: When larger tumor inocula were injected, the contamination of both trocars (p = 0.005, Kendall's rank correlation) and trocar sites (p = 0.04, Kendall's rank correlation) increased. The deposition of cells on a trocar site was linked to contamination of its trocar (p = 0.03, chi-square), but the contamination of trocars did not always result in trocar-site contamination (p = 0.5, chi-square). Increased volumes of gas insufflation caused increased intraabdominal movement of tumour cells (p = 0.01, Kendall's rank correlation), although this did not lead to greater contamination of trocars or port sites (p = 0.82, Kendall's rank correlation). Decreased insufflation pressures resulted in increased contamination of trocars and port sites (p = 0.01, Kendall's rank correlation). CONCLUSIONS: If clinical situations parallel this study, strategies such as increasing insufflation pressure, reducing episodes of desufflation and gas leaks, and using frequent intraabdominal lavage may help to reduce the numbers of viable tumor cells displaced to port sites during laparoscopic surgery for intraabdominal malignancy. This may reduce the rate of port-site metastases.

Experimental study of the material composition of laparoscopic ports on tumour cell adherence.

BACKGROUND: Laparoscopic resection of intra-abdominal malignancies has yet to be widely adopted, partly because of concerns over the possible increase in the rate of port-site metastasis. The aetiology of these is unclear, but the laparoscopic instrumentation used may influence the deposition of tumour cells at the port sites during operation. An in vitro model to examine tumour cell adherence to laparoscopic ports and to port sites was developed to examine this hypothesis. METHODS: A pilot study (study 1) was performed in which six smooth plastic, six ribbed plastic and six metal ports were introduced through the shaved abdominal wall of a cadaveric sheep and suspended in a water-bath containing radiolabelled LIM 1215 human colonic cancer cells for 30 min. Radioactivity on both ports and port sites was measured and the number of cells adherent to each structure was calculated. The study was expanded to include a further 36 smooth plastic ports and 36 metal ports (study 2). RESULTS: In study 1 metal ports were found to have significantly more adherent cells than plastic ports (P = 0.004), as did ribbed ports when compared with smooth ports (P < 0.05). In study 2 increased numbers of cells were again detected on metal ports (P < 0.001) when compared with plastic ports. Significantly greater numbers of cells were also detected on the sites through which metal ports had passed than on sites through which plastic ports had passed (P = 0.03). CONCLUSION: In this model, the use of metal ports as opposed to plastic ports resulted in increased deposition of tumour cells on both ports and port sites.