Daikenchuto for reducing postoperative ileus in patients undergoing elective abdominal surgery

Reason for withdrawal: Serious breach of Cochrane's conflict of interest policy. A ruling by Cochrane's Funding Arbiters that a Cochrane Review has seriously breached Cochrane's conflict of interest policy.

Computed tomography for diagnosis of acute appendicitis in adults

BACKGROUND

Diagnosing acute appendicitis (appendicitis) based on clinical evaluation, blood testing, and urinalysis can be difficult. Therefore, in persons with suspected appendicitis, abdominopelvic computed tomography (CT) is often used as an add-on test following the initial evaluation to reduce remaining diagnostic uncertainty. The aim of using CT is to assist the clinician in discriminating between persons who need surgery with appendicectomy and persons who do not.

OBJECTIVES

Primary objective Our primary objective was to evaluate the accuracy of CT for diagnosing appendicitis in adults with suspected appendicitis. Secondary objectives Our secondary objectives were to compare the accuracy of contrast-enhanced versus non-contrast-enhanced CT, to compare the accuracy of low-dose versus standard-dose CT, and to explore the influence of CT-scanner generation, radiologist experience, degree of clinical suspicion of appendicitis, and aspects of methodological quality on diagnostic accuracy.

SEARCH METHODS

We searched MEDLINE, Embase, and Science Citation Index until 16 June 2017. We also searched references lists. We did not exclude studies on the basis of language or publication status.

SELECTION CRITERIA

We included prospective studies that compared results of CT versus outcomes of a reference standard in adults (> 14 years of age) with suspected appendicitis. We excluded studies recruiting only pregnant women; studies in persons with abdominal pain at any location and with no particular suspicion of appendicitis; studies in which all participants had undergone ultrasonography (US) before CT and the decision to perform CT depended on the US outcome; studies using a case-control design; studies with fewer than 10 participants; and studies that did not report the numbers of true-positives, false-positives, false-negatives, and true-negatives. Two review authors independently screened and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected the data from each study and evaluated methodological quality according to the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate random-effects model to obtain summary estimates of sensitivity and specificity.

MAIN RESULTS

We identified 64 studies including 71 separate study populations with a total of 10,280 participants (4583 with and 5697 without acute appendicitis). Estimates of sensitivity ranged from 0.72 to 1.0 and estimates of specificity ranged from 0.5 to 1.0 across the 71 study populations. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.93 to 0.96), and summary specificity was 0.94 (95% CI 0.92 to 0.95). At the median prevalence of appendicitis (0.43), the probability of having appendicitis following a positive CT result was 0.92 (95% CI 0.90 to 0.94), and the probability of having appendicitis following a negative CT result was 0.04 (95% CI 0.03 to 0.05). In subgroup analyses according to contrast enhancement, summary sensitivity was higher for CT with intravenous contrast (0.96, 95% CI 0.92 to 0.98), CT with rectal contrast (0.97, 95% CI 0.93 to 0.99), and CT with intravenous and oral contrast enhancement (0.96, 95% CI 0.93 to 0.98) than for unenhanced CT (0.91, 95% CI 0.87 to 0.93). Summary sensitivity of CT with oral contrast enhancement (0.89, 95% CI 0.81 to 0.94) and unenhanced CT was similar. Results show practically no differences in summary specificity, which varied from 0.93 (95% CI 0.90 to 0.95) to 0.95 (95% CI 0.90 to 0.98) between subgroups. Summary sensitivity for low-dose CT (0.94, 95% 0.90 to 0.97) was similar to summary sensitivity for standard-dose or unspecified-dose CT (0.95, 95% 0.93 to 0.96); summary specificity did not differ between low-dose and standard-dose or unspecified-dose CT. No studies had high methodological quality as evaluated by the QUADAS-2 tool. Major methodological problems were poor reference standards and partial verification primarily due to inadequate and incomplete follow-up in persons who did not have surgery.

AUTHORS' CONCLUSIONS

The sensitivity and specificity of CT for diagnosing appendicitis in adults are high. Unenhanced standard-dose CT appears to have lower sensitivity than standard-dose CT with intravenous, rectal, or oral and intravenous contrast enhancement. Use of different types of contrast enhancement or no enhancement does not appear to affect specificity. Differences in sensitivity and specificity between low-dose and standard-dose CT appear to be negligible. The results of this review should be interpreted with caution for two reasons. First, these results are based on studies of low methodological quality. Second, the comparisons between types of contrast enhancement and radiation dose may be unreliable because they are based on indirect comparisons that may be confounded by other factors.

Follow-up strategies for patients treated for non-metastatic colorectal cancer

BACKGROUND

This is the fourth update of a Cochrane Review first published in 2002 and last updated in 2016.It is common clinical practice to follow patients with colorectal cancer for several years following their curative surgery or adjuvant therapy, or both. Despite this widespread practice, there is considerable controversy about how often patients should be seen, what tests should be performed, and whether these varying strategies have any significant impact on patient outcomes.

OBJECTIVES

To assess the effect of follow-up programmes (follow-up versus no follow-up, follow-up strategies of varying intensity, and follow-up in different healthcare settings) on overall survival for patients with colorectal cancer treated with curative intent. Secondary objectives are to assess relapse-free survival, salvage surgery, interval recurrences, quality of life, and the harms and costs of surveillance and investigations.

SEARCH METHODS

For this update, on 5 April 2109 we searched CENTRAL, MEDLINE, Embase, CINAHL, and Science Citation Index. We also searched reference lists of articles, and handsearched the Proceedings of the American Society for Radiation Oncology. In addition, we searched the following trials registries: ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. We contacted study authors. We applied no language or publication restrictions to the search strategies.

SELECTION CRITERIA

We included only randomised controlled trials comparing different follow-up strategies for participants with non-metastatic colorectal cancer treated with curative intent.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently determined study eligibility, performed data extraction, and assessed risk of bias and methodological quality. We used GRADE to assess evidence quality.

MAIN RESULTS

We identified 19 studies, which enrolled 13,216 participants (we included four new studies in this second update). Sixteen out of the 19 studies were eligible for quantitative synthesis. Although the studies varied in setting (general practitioner (GP)-led, nurse-led, or surgeon-led) and 'intensity' of follow-up, there was very little inconsistency in the results.Overall survival: we found intensive follow-up made little or no difference (hazard ratio (HR) 0.91, 95% confidence interval (CI) 0.80 to 1.04: I² = 18%; high-quality evidence). There were 1453 deaths among 12,528 participants in 15 studies. In absolute terms, the average effect of intensive follow-up on overall survival was 24 fewer deaths per 1000 patients, but the true effect could lie between 60 fewer to 9 more per 1000 patients.Colorectal cancer-specific survival: we found intensive follow-up probably made little or no difference (HR 0.93, 95% CI 0.81 to 1.07: I² = 0%; moderate-quality evidence). There were 925 colorectal cancer deaths among 11,771 participants enrolled in 11 studies. In absolute terms, the average effect of intensive follow-up on colorectal cancer-specific survival was 15 fewer colorectal cancer-specific survival deaths per 1000 patients, but the true effect could lie between 47 fewer to 12 more per 1000 patients.Relapse-free survival: we found intensive follow-up made little or no difference (HR 1.05, 95% CI 0.92 to 1.21; I² = 41%; high-quality evidence). There were 2254 relapses among 8047 participants enrolled in 16 studies. The average effect of intensive follow-up on relapse-free survival was 17 more relapses per 1000 patients, but the true effect could lie between 30 fewer and 66 more per 1000 patients.Salvage surgery with curative intent: this was more frequent with intensive follow-up (risk ratio (RR) 1.98, 95% CI 1.53 to 2.56; I² = 31%; high-quality evidence). There were 457 episodes of salvage surgery in 5157 participants enrolled in 13 studies. In absolute terms, the effect of intensive follow-up on salvage surgery was 60 more episodes of salvage surgery per 1000 patients, but the true effect could lie between 33 to 96 more episodes per 1000 patients.Interval (symptomatic) recurrences: these were less frequent with intensive follow-up (RR 0.59, 95% CI 0.41 to 0.86; I² = 66%; moderate-quality evidence). There were 376 interval recurrences reported in 3933 participants enrolled in seven studies. Intensive follow-up was associated with fewer interval recurrences (52 fewer per 1000 patients); the true effect is between 18 and 75 fewer per 1000 patients.Intensive follow-up probably makes little or no difference to quality of life, anxiety, or depression (reported in 7 studies; moderate-quality evidence). The data were not available in a form that allowed analysis.Intensive follow-up may increase the complications (perforation or haemorrhage) from colonoscopies (OR 7.30, 95% CI 0.75 to 70.69; 1 study, 326 participants; very low-quality evidence). Two studies reported seven colonoscopic complications in 2292 colonoscopies, three perforations and four gastrointestinal haemorrhages requiring transfusion. We could not combine the data, as they were not reported by study arm in one study.The limited data on costs suggests that the cost of more intensive follow-up may be increased in comparison with less intense follow-up (low-quality evidence). The data were not available in a form that allowed analysis.

AUTHORS' CONCLUSIONS

The results of our review suggest that there is no overall survival benefit for intensifying the follow-up of patients after curative surgery for colorectal cancer. Although more participants were treated with salvage surgery with curative intent in the intensive follow-up groups, this was not associated with improved survival. Harms related to intensive follow-up and salvage therapy were not well reported.

Prolonged thromboprophylaxis with low molecular weight heparin for abdominal or pelvic surgery

BACKGROUND

This an update of the review first published in 2009.Major abdominal and pelvic surgery carries a high risk of venous thromboembolism (VTE). The efficacy of thromboprophylaxis with low molecular weight heparin (LMWH) administered during the in-hospital period is well-documented, but the optimal duration of prophylaxis after surgery remains controversial. Some studies suggest that patients undergoing major abdominopelvic surgery benefit from prolongation of the prophylaxis up to 28 days after surgery.

OBJECTIVES

To evaluate the efficacy and safety of prolonged thromboprophylaxis with LMWH for at least 14 days after abdominal or pelvic surgery compared with thromboprophylaxis administered during the in-hospital period only in preventing late onset VTE.

SEARCH METHODS

We performed electronic searches on 28 October 2017 in the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, LILACS and registered trials (Clinicaltrials.gov October 28, 2017 and World Health Organization International Clinical Trials Registry Platform (ICTRP) 28 October 2017). Abstract books from major congresses addressing thromboembolism were handsearched from 1976 to 28 October 2017, as were reference lists from relevant studies.

SELECTION CRITERIA

We assessed randomized controlled clinical trials (RCTs) comparing prolonged thromboprophylaxis (≥ fourteen days) with any LMWH agent with placebo, or other methods, or both to thromboprophylaxis during the admission period only. The population consisted of persons undergoing abdominal or pelvic surgery for both benign and malignant pathology. The outcome measures included VTE (deep venous thrombosis (DVT) or pulmonary embolism (PE)) as assessed by objective means (venography, ultrasonography, pulmonary ventilation/perfusion scintigraphy, spiral computed tomography (CT) scan or autopsy). We excluded studies exclusively reporting on clinical diagnosis of VTE without objective confirmation.

DATA COLLECTION AND ANALYSIS

Review authors identified studies and extracted data. Outcomes were VTE (DVT or PE) assessed by objective means. Safety outcomes were defined as bleeding complications and mortality within three months after surgery. Sensitivity analyses were also performed with unpublished studies excluded, and with study participants limited to those undergoing solely open and not laparoscopic surgery. We used a fixed-effect model for analysis.

MAIN RESULTS

We identified seven RCTs (1728 participants) evaluating prolonged thromboprophylaxis with LMWH compared with control or placebo. The searches resulted in 1632 studies, of which we excluded 1528. One hundred and four abstracts, eligible for inclusion, were assessed of which seven studies met the inclusion criteria.For the primary outcome, the incidence of overall VTE after major abdominal or pelvic surgery was 13.2% in the control group compared to 5.3% in the patients receiving out-of-hospital LMWH (Mantel Haentzel (M-H) odds ratio (OR) 0.38, 95% confidence interval (CI) 0.26 to 0.54; I² = 28%; moderate-quality evidence).For the secondary outcome of all DVT, seven studies, n = 1728, showed prolonged thromboprophylaxis with LMWH to be associated with a statistically significant reduction in the incidence of all DVT (M-H OR 0.39, 95% CI 0.27 to 0.55; I² = 28%; moderate-quality evidence).We found a similar reduction when analysis was limited to incidence in proximal DVT (M-H OR 0.22, 95% CI 0.10 to 0.47; I² = 0%; moderate-quality evidence).The incidence of symptomatic VTE was also reduced from 1.0% in the control group to 0.1% in patients receiving prolonged thromboprophylaxis, which approached significance (M-H OR 0.30, 95% CI 0.08 to 1.11; I² = 0%; moderate-quality evidence).No difference in the incidence of bleeding between the control and LMWH group was found, 2.8% and 3.4%, respectively (M-H OR 1.10, 95% CI 0.67 to 1.81; I² = 0%; moderate-quality evidence).No difference in mortality between the control and LMWH group was found, 3.8% and 3.9%, respectively (M-H OR 1.15, 95% CI 0.72 to 1.84; moderate-quality evidence).Estimates of heterogeneity ranged between 0% and 28% depending on the analysis, suggesting low or unimportant heterogeneity.

AUTHORS' CONCLUSIONS

Prolonged thromboprophylaxis with LMWH significantly reduces the risk of VTE compared to thromboprophylaxis during hospital admittance only, without increasing bleeding complications or mortality after major abdominal or pelvic surgery. This finding also holds true for DVT alone, and for both proximal and symptomatic DVT. The quality of the evidence is moderate and provides moderate support for routine use of prolonged thromboprophylaxis. Given the low heterogeneity between studies and the consistent and moderate evidence of a decrease in risk for VTE, our findings suggest that additional studies may help refine the degree of risk reduction but would be unlikely to significantly influence these findings. This updated review provides additional evidence and supports the previous results reported in the 2009 review.

Early enteral nutrition within 24 hours of lower gastrointestinal surgery versus later commencement for length of hospital stay and postoperative complications

BACKGROUND

This is an update of the review last published in 2011. It focuses on early postoperative enteral nutrition after lower gastrointestinal surgery. Traditional management consisted of 'nil by mouth', where patients receive fluids followed by solids after bowel function has returned. Although several trials have reported lower incidence of infectious complications and faster wound healing upon early feeding, other trials have shown no effect. The immediate advantage of energy intake (carbohydrates, protein or fat) could enhance recovery with fewer complications, and this warrants a systematic evaluation.

OBJECTIVES

To evaluate whether early commencement of postoperative enteral nutrition (within 24 hours), oral intake and any kind of tube feeding (gastric, duodenal or jejunal), compared with traditional management (delayed nutritional supply) is associated with a shorter length of hospital stay (LoS), fewer complications, mortality and adverse events in patients undergoing lower gastrointestinal surgery (distal to the ligament of Treitz).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, the Cochrane Library 2017, issue 10), Ovid MEDLINE (1950 to 15 November 2017), Ovid Embase (1974 to 15 November 2017). We also searched for ongoing trials in ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (15 November 2017). We handsearched reference lists of identified studies and previous systematic reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCT) comparing early commencement of enteral nutrition (within 24 hours) with no feeding in adult participants undergoing lower gastrointestinal surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality using the Cochrane 'Risk of bias' tool tailored to this review and extracted data. Data analyses were conducted according to the Cochrane recommendations.We rated the quality of evidence according to GRADE.Primary outcomes were LoS and postoperative complications (wound infections, intraabdominal abscesses, anastomotic dehiscence, pneumonia).Secondary outcomes were: mortality, adverse events (nausea, vomiting), and quality of life (QoL).LoS was estimated using mean difference (MD (presented as mean +/- SD). For other outcomes we estimated the common risk ratio (RR) and calculated the associated 95% confidence intervals. For analysis, we used an inverse-variance random-effects model for the primary outcome (LoS) and Mantel-Haenszel random-effects models for the secondary outcomes. We also performed Trial Sequential Analyses (TSA).

MAIN RESULTS

We identified 17 RCTs with 1437 participants undergoing lower gastrointestinal surgery. Most studies were at high or unclear risk of bias in two or more domains. Six studies were judged as having low risk of selection bias for random sequence generation and insufficient details were provided for judgement on allocation concealment in all 17 studies. With regards to performance and deception bias; 14 studies reported no attempt to blind participants and blinding of personnel was not discussed either. Only one study was judged as low risk of bias for blinding of outcome assessor. With regards to incomplete outcome data, three studies were judged to be at high risk because they had more than 10% difference in missing data between groups. For selective reporting, nine studies were judged as unclear as protocols were not provided and eight studies had issues with either missing data or incomplete reporting of results.LOS was reported in 16 studies (1346 participants). The mean LoS ranged from four days to 16 days in the early feeding groups and from 6.6 days to 23.5 days in the control groups. Mean difference (MD) in LoS was 1.95 (95% CI, -2.99 to -0.91, P < 0.001) days shorter in the early feeding group. However, there was substantial heterogeneity between included studies (I² = 81, %, Chi² = 78.98, P < 0.00001), thus the overall quality of evidence for LoS is low. These results were confirmed by the TSA showing that the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit.We found no differences in the incidence of postoperative complications: wound infection (12 studies, 1181 participants, RR 0.99, 95%CI 0.64 to 1.52, very low-quality evidence), intraabdominal abscesses (6 studies, 554 participants, RR 1.00, 95%CI 0.26 to 3.80, low-quality evidence), anastomotic leakage/dehiscence (13 studies, 1232 participants, RR 0.78, 95%CI 0.38 to 1.61, low-quality evidence; number needed to treat for an additional beneficial outcome (NNTB) = 100), and pneumonia (10 studies, 954 participants, RR 0.88, 95%CI 0.32 to 2.42, low-quality evidence; NNTB = 333).Mortality was reported in 12 studies (1179 participants), and showed no between-group differences (RR = 0.56, 95%CI, 0.21 to 1.52, P = 0.26, I² = 0%, Chi² = 3.08, P = 0.96, low-quality evidence). The most commonly reported cause of death was anastomotic leakage, sepsis and acute myocardial infarction.Seven studies (613 participants) reported vomiting (RR 1.23, 95%CI, 0.96 to 1.58, P = 0.10, I² = 0%, Chi² = 4.98, P = 0.55, low-quality evidence; number needed to treat for an additional harmful outcome (NNTH) = 19), and two studies (118 participants) reported nausea (RR 0.95, 0.71 to 1.26, low-quality evidence). Four studies reported combined nausea and vomiting (RR 0.94, 95%CI 0.51 to 1.74, very low-quality evidence). One study reported QoL assessment; the scores did not differ between groups at 30 days after discharge on either QoL scale EORTC QLQ-C30 or EORTC QlQ-OV28 (very low-quality evidence).

AUTHORS' CONCLUSIONS

This review suggests that early enteral feeding may lead to a reduced postoperative LoS, however cautious interpretation must be taken due to substantial heterogeneity and low-quality evidence. For all other outcomes (postoperative complications, mortality, adverse events, and QoL) the findings are inconclusive, and further trials are justified to enhance the understanding of early feeding for these. In this updated review, only a few additional studies have been included, and these were small and of poor quality.To improve the evidence, future trials should address quality issues and focus on clearly defining and measuring postoperative complications to allow for better comparison between studies. However due to the introduction of fast track protocols which already include an early feeding component, future trials may be challenging. A more feasible trial may be to investigate the effect of differing postoperative energy intake regimens on relevant outcomes.