Meta‐analysis of standard,restrictive and supplemental fluid administration in colorectal surgery

Background:

Optimal fluid therapy for colorectal surgery remains uncertain.

Methods:

A simple model was applied to define standard, restrictive and supplemental fluid administration. These definitions enabled pooling of data from different trials. Randomized controlled trials on fluid amount (standard versus restrictive or supplemental amount) and on guidance for fluid administration (goal‐directed fluid therapy by oesophageal Doppler‐derived variables versus conventional haemodynamic variables) in patients with colorectal resection were eligible for inclusion. The primary outcome measure was postoperative morbidity. Secondary endpoints were mortality, cardiopulmonary morbidity, wound infection, anastomotic failure, recovery of bowel function and hospital stay. A random‐effects model was applied.

Results:

Nine randomized controlled trials were included. Restrictive fluid amount (odds ratio (OR) 0·41 (95 per cent confidence interval (c.i.) 0·22 to 0·77); P = 0·005) and goal‐directed fluid therapy by means of oesophageal Doppler‐derived variables (OR 0·43 (95 per cent c.i. 0·26 to 0·71); P = 0·001) significantly reduced overall morbidity. There were no significant differences in the secondary endpoints analysed.

Conclusion:

Using standardized definitions, this meta‐analysis suggests that restrictive rather than standard fluid amount according to current textbook opinion, and goal‐directed fluid therapy rather than fluid therapy guided by conventional haemodynamic variables, reduce morbidity after colorectal resection. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.     

Functional Outcome After Restorative Proctocolectomy in Pigs: Comparing a Novel Transverse Ileal Pouch to the J-Pouch and Straight Ileoanal Anastomosis

Background  Restorative proctocolectomy followed by an ileoanal J-pouch procedure is the therapy of choice for patients with familial adenomatous polyposis and ulcerative colitis. After low anterior rectal resection, the authors have reported on a novel, less complex pouch configuration, a transverse coloplasty pouch. The aim of the present work was to apply this new design to the ileal pouch construction, to evaluate feasibility, and to measure functional results in comparison with the J-pouch and the straight ileoanal anastomosis using the pig as an animal model. Methods  Twenty-three pigs underwent restorative proctocolectomy followed by reconstruction with straight ileoanal anastomosis (IAA; n = 5), J-pouch (n = 7), and a transverse ileal pouch (TIP; n = 11). Pigs were followed for 6 days postoperatively. Peristaltic function was assessed by manometry proximal to the pouch, in the reservoir, and at the level of the ileoanal anastomosis. Functional outcome was monitored by semiquantitative assessment of the general condition of the animals, postoperative feeding habits, and stool frequency and consistency. A Fourier analysis was performed in order to compare peristalsis in the ileal reservoirs. The reservoir volume was measured in situ by triple contrast computed tomography scan with 3D reconstruction. Results  Seventeen animals survived for 1 week. There was no difference in the general condition or the feeding habits of the groups. A significant number of pigs with the TIP pouch (7/10) had semisolid or formed stools as opposed to liquid stools after J-pouch (6/6) and IAA (4/5; p = 0.01). TIP animals had a lower stool frequency (3.2 ± 1.14 per day) on day 6 after the operation than pigs with J-pouch, 5.33 ± 1,03, and IAA, 4.6 ± 1.82 (p = 0.0036). The in situ volume of the pouches did not differ significantly. The Fourier analysis demonstrated a disruption of peristalsis by the J-pouch and the TIP reconstruction but not after IAA. Conclusion  The function of ileoanal reservoirs after proctocolectomy may result from the disruption of properistaltic waves after pouch formation. The mechanism of peristalsis disruption is independent of the in situ volume of the pouch. This work was funded by Covidien Germany. F. H. Schmitz-Winnenthal and M. Kadmon contributed equally to this work.     

Meta-Analysis of the Clamp-Crushing Technique for Transection of the Parenchyma in Elective Hepatic Resection: Back to Where We Started?

Background  After introduction of the clamp-crushing technique in the 1970s, various devices have been developed for transection of the liver with the aim of further reducing blood loss and improving the outcome of patients who undergo hepatic resection. We performed a meta-analysis to quantitatively compare the clamp-crushing technique to any subsequently introduced transection technique with respect to patients’ perioperative outcome. Methods  A systematic literature search was conducted to identify randomized controlled trials comparing the clamp-crushing technique to any alternative method of hepatic transection. Relative risks (RR) were calculated for each outcome and reported along with their 95% confidence intervals (95% CI). Meta-analyses were stratified for the various types of transection techniques compared with the clamp-crushing technique and were carried out by a random effects model. Results  Seven randomized controlled trials with a total of 554 patients were included in final analyses. Analyses of overall morbidity (RR .89; 95% CI, .63–1.25), biliary leakage (RR 1.03; 95% CI, .50–2.13), transfusion rates (RR .69; 95% CI, .31–1.51), and mortality RR (.20; 95% CI, .02–1.65) revealed no difference between the clamp-crushing and alternative transection techniques. None of the identified studies demonstrated a clinically important benefit of an alternative transection method in terms of blood loss, parenchymal injury, transection time, and hospital stay. Conclusions  This meta-analysis does not indicate a benefit of any alternative transection technique on patients’ perioperative outcome compared with the clamp-crushing technique. The clamp-crushing technique remains the reference technique for transection of the parenchyma in elective hepatic resection. Nuh N. Rahbari, Moritz Koch authors contributed equally to this article.     

Validation of Prognostic Scoring Systems for Patients Undergoing Resection of Colorectal Cancer Liver Metastases

Background  

Several prognostic scoring systems have been established for patients undergoing resection of colorectal cancer (CRC) liver metastases; however, comparative analyses of their prognostic relevance is still lacking in the literature. The aim of the present study was to assess the predictive value of five published scoring systems in an independent patient cohort for the purpose of external validation.     

Invasion front-specific expression and prognostic significance of microRNA in colorectal liver metastases

The tumor edge of colorectal cancer and its adjacent peritumoral tissue is characterized by an invasion front-specific expression of genes that contribute to angiogenesis or epithelial-to-mesenchymal transition. Dysregulation of these genes has a strong impact on the invasion behavior of tumor cells. However, the invasion front-specific expression of microRNA (miRNA) still remains unclear. Therefore, the aim of the present study was to investigate miRNA expression patterns at the invasion front of colorectal liver metastases. Laser microdissection of colorectal liver metastases was performed to obtain separate tissue compartments from the tumor center, tumor invasion front, liver invasion front and pure liver parenchyma. Microarray expression analysis revealed 23 miRNA downregulated in samples from the tumor invasion front with respect to the same miRNA in the liver, the liver invasion front or the tumor center. By comparing samples from the liver invasion front with samples from pure liver parenchyma, the tumor invasion front and the tumor center, 13 miRNA were downregulated. By quantitative RT-PCR, we validated the liver invasion front-specific downregulation of miR-19b, miR-194, let-7b and miR-1275 and the tumor invasion front-specific downregulation of miR-143, miR- 145, let-7b and miR-638. Univariate analysis demonstrated that enhanced expression of miR-19b and miR-194 at the liver invasion front, and decreased expression of let-7 at the tumor invasion front, is an adverse prognostic marker of tumor recurrence and overall survival. In conclusion, the present study suggests that invasion front-specific downregulation of miRNA in colorectal liver metastases plays a pivotal role in tumor progression.     

Changes in abortion provider practices in response to the Partial-Birth Abortion Ban Act of 2003

Background

The April 2007 Supreme Court Gonzalez v. Gonzalez v. Carhart decision upheld the Partial-Birth Abortion Ban Act of 2003. We conducted a pilot study that measured the impact of the ban in one state with a diverse pool of second-trimester abortion providers.

Study Design

A survey was administered via telephone to key informants at each facility in Massachusetts where second-trimester abortions are performed in order to assess clinical and administrative changes following the Supreme Court decision.

Results

Five hospital-based practices introduced injections to induce fetal demise prior to dilation and evacuation for later second-trimester abortions. One site stopped providing dilation and evacuation abortions in the absence of fetal or maternal indications, and another significantly decreased its volume of procedures. Training opportunities were decreased, and costs at three facilities increased.

Conclusions

The Partial-Birth Abortion Ban Act of 2003 resulted in a range of practice changes in Massachusetts, particularly in hospitals. These changes reflect adherence to legal and policy mandates and not the availability of new scientific evidence. Further study to assess the impact of the ban in states with fewer providers is warranted.     

Surgery insight: surgical management of pancreatic cancer

Pancreatic ductal adenocarcinoma is a common malignancy of the gastrointestinal tract. The number of new cases diagnosed and the number of deaths each year are almost identical, demonstrating the particularly dismal prognosis for patients affected by this disease. Despite recent advances in the field of medical and radiation oncology, and the introduction of neoadjuvant and adjuvant regimens, surgery remains the single most important modality for the treatment of pancreatic ductal adenocarcinoma. Surgery for pancreatic cancer is widely viewed as a complex procedure associated with considerable perioperative morbidity and mortality. Many aspects of surgery for pancreatic cancer, such as the extent of resection, the value of vascular resection, the use of laparoscopy, and the importance of treatment at high-volume centers, are currently under debate. This Review describes the current status of surgical treatment for pancreatic ductal adenocarcinoma, and highlights the new developments in this field.