Dirk T. Ubbink

Acute appendicitis: meta-analysis of diagnostic performance of CT and graded compression US related to prevalence of disease.

PURPOSE This study was a head-to-head comparison of graded compression ultrasonography (US) and computed tomography (CT) in helping diagnose acute appendicitis with an emphasis on diagnostic value at different disease prevalences, commonly occurring in various hospital settings. MATERIALS AND METHODS MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched from January 1966 to February 2006. Prospective trials were selected if they (a) compared graded compression US and CT in the same patient population; (b) included more than 10 patients, otherwise, the study was considered a case report; (c) evaluated mainly adults or adolescents; (d) used surgery and/or clinical follow-up as reference standard; and (e) reported data to calculate 2 x 2 contingency tables for graded compression US and CT. Estimates of sensitivity, specificity, and positive and negative likelihood ratios (LRs) for US and CT were calculated. Posttest probabilities after CT and US were calculated for various clinically relevant prevalences. RESULTS Six studies were included, evaluating 671 patients (mean age range, 26-38 years); prevalence of acute appendicitis was 50% (range, 13%-77%). Positive LR was 9.29 (95% confidence interval [CI]: 6.9, 12.6) for CT and 4.50 (95% CI: 3.0, 6.7; P = .011) for US, yielding posttest probabilities for positive tests of 90% and 82%, respectively. Negative LR was 0.10 (95% CI: 0.06, 0.17) for CT and 0.27 (95% CI: 0.17, 0.43) for US (P = .013), resulting in posttest probabilities of 9% and 21%, respectively. Posttest probabilities for positive tests were markedly decreased at lower prevalences. CONCLUSION In head-to-head comparison studies of diagnostic imaging, CT had a better test performance than did graded compression US in diagnosing appendicitis. Ignoring the relationship between prevalence (pretest probability) and diagnostic value may lead to an inaccurate estimation of diagnostic performance.

A systematic review of topical negative pressure therapy for acute and chronic wounds

Topical negative pressure (TNP) therapy is becoming increasingly popular for all kinds of wounds. Its clinical and cost effectiveness is unclear.

Bipolar versus Monopolar Transurethral Resection of the Prostate: A Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT Incorporation of bipolar technology in transurethral resection (TUR) of the prostate (TURP) potentially offers advantages over monopolar TURP (M-TURP). OBJECTIVE To evaluate the evidence by a meta-analysis, based on randomized controlled trials (RCTs) comparing bipolar TURP (B-TURP) with M-TURP for benign prostatic obstruction. Primary end points included efficacy (maximum flow rate [Q(max)], International Prostate Symptom Score) and safety (adverse events). Secondary end points included operation time and duration of irrigation, catheterization, and hospitalization. EVIDENCE ACQUISITION Based on a detailed, unrestricted strategy, the literature was searched up to February 19, 2009, using Medline, Embase, Science Citation Index, and the Cochrane Library to detect all relevant RCTs. Methodological quality assessment of the trials was based on the Dutch Cochrane Collaboration checklist. Meta-analysis was performed using Review Manager 5.0. EVIDENCE SYNTHESIS Sixteen RCTs (1406 patients) were included. Overall trial quality was low (eg, allocation concealment and blinding of outcome assessors were poorly reported). No clinically relevant differences in short-term (12-mo) efficacy were detected (Q(max): weighted mean difference [WMD]: 0.72 ml/s; 95% confidence interval [CI], 0.08-1.35; p=0.03). Data on follow-up of >12 mo are scarce for B-TURP, precluding long-term efficacy evaluation. Treating 50 patients (95% CI, 33-111) and 20 patients (95% CI, 10-100) with B-TURP results in one fewer case of TUR syndrome (risk difference [RD]: 2.0%; 95% CI, 0.9-3.0%; p=0.01) and one fewer case of clot retention (RD: 5.0%; 95% CI, 1.0-10%; p=0.03), respectively. Operation times, transfusion rates, retention rates after catheter removal, and urethral complications did not differ significantly. Irrigation and catheterization duration was significantly longer with M-TURP (WMD: 8.75 h; 95% CI, 6.8-10.7 and WMD: 21.77 h; 95% CI, 19.22-24.32; p<0.00001, respectively). Inferences for hospitalization duration could not be made. PlasmaKinetic TURP showed an improved safety profile. Data on TUR in saline (TURis) are not yet mature to permit safe conclusions. CONCLUSIONS No clinically relevant differences in short-term efficacy exist between the two techniques, but B-TURP is preferable due to a more favorable safety profile (lower TUR syndrome and clot retention rates) and shorter irrigation and catheterization duration. Well-designed multicentric/international RCTs with long-term follow-up and cost analysis are still needed.

Foot salvage and improvement of microvascular blood flow as a result of epidural spinal cord electrical stimulation

Epidural spinal cord electrical stimulation has been suggested as an alternative treatment in patients with limb-threatening ischemia in whom vascular reconstructive surgery is not possible anymore. We studied the effects of epidural spinal cord electrical stimulation on microcirculatory blood flow in 20 patients with ischemic rest pain and ulcers. Angiography showed occluded crural arteries technically unsuitable for reconstructive surgery. Intravital capillary microscopy was used to assess capillary density and diameter and red blood cell velocity before and after a 1-minute period of arterial occlusion. After epidural spinal cord electrical stimulation 18 patients claimed immediate pain relief, which was confirmed by intravital capillary microscopy. Capillary density increased from 10 to 19/mm2 (p less than 0.001), red blood cell velocity increased from 0.088 to 0.496 mm/sec (p less than 0.001), and peak red blood cell velocity after arterial occlusion increased from 0.092 to 0.548 mm/sec (p less than 0.001). Two patients had no immediate pain relief; they did not show improvement of microcirculatory perfusion, and amputation was necessary. During the follow-up period (3 months to 3 years, mean 27 months), six other patients had recurrent ischemic pain, and amputation was necessary. In 12 patients pain relief continued, and ischemic ulcers healed; capillary microscopy confirmed improved microcirculatory blood flow. Microcirculatory parameters were significantly higher in respondents than in nonrespondents (p less than 0.001). Life-table analysis revealed a cumulative foot salvage of 80% and 56% after 1 and 2 years, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

START Trial: a pilot study on STimulation of ARTeriogenesis using subcutaneous application of granulocyte-macrophage colony-stimulating factor as a new treatment for peripheral vascular disease.

Background—Granulocyte-macrophage colony-stimulating factor (GM-CSF) was recently shown to increase collateral flow index in patients with coronary artery disease. Experimental models showed beneficial effects of GM-CSF on collateral artery growth in the peripheral circulation. Thus, in the present study, we evaluated the effects of GM-CSF in patients with peripheral artery disease. Methods and Results—A double-blinded, randomized, placebo-controlled study was performed in 40 patients with moderate or severe intermittent claudication. Patients were treated with placebo or subcutaneously applied GM-CSF (10 &mgr;g/kg) for a period of 14 days (total of 7 injections). GM-CSF treatment led to a strong increase in total white blood cell count and C-reactive protein. Monocyte fraction initially increased but thereafter decreased significantly as compared with baseline. Both the placebo group and the treatment group showed a significant increase in walking distance at day 14 (placebo: 127±67 versus 184±87 meters, P=0.03, GM-CSF: 126±66 versus 189±141 meters, P=0.04) and at day 90. Change in walking time, the primary end point of the study, was not different between groups. No change in ankle-brachial index was found on GM-CSF treatment at day 14 or at day 90. Laser Doppler flowmetry measurements showed a significant decrease in microcirculatory flow reserve in the control group (P=0.03) and no change in the GM-CSF group. Conclusions—The present study does not support the use of GM-CSF for treatment of patients with moderate or severe intermittent claudication. Issues that need to be addressed are dosing, the selection of patients, and potential differences between GM-CSF effects in the coronary and the peripheral circulation.

Meta Analysis on Mortality of Ruptured Abdominal Aortic Aneurysms

OBJECTIVES To assess the mortality of patients with ruptured abdominal aortic aneurysms undergoing open surgery and examine changes in mortality over time. METHODS Literature databases were searched for relevant articles published between 1991 and 2006. Two reviewers independently performed study inclusion and data extraction. Primary outcome measure was 30 day or in-hospital mortality. Subgroup analyses were performed examining the effect of population- and hospital-based studies, hospital volume and type of surgeon. RESULTS From a total of 1419 identified studies, 145 observational studies met the inclusion criteria of which 116 were included in the systematic review comprising 60,822 patients. Overall mortality was 48.5% (95% CI: 48.1-48.9%) and did not change significantly over the years. Age increased over the years. For overall mortality a trend was seen in favour of high-volume hospitals. CONCLUSIONS This meta-analysis suggests that mortality of patients with RAAA treated by open surgery has not changed over the past 15 years. This could be explained by increased age of patients undergoing RAAA repair.

Long-term outcomes following laparoscopically assisted versus open ileocolic resection for Crohn's disease.

Long‐term results of laparoscopically assisted versus open ileocolic resection for Crohns disease were evaluated in a randomized trial.

Systematic review of dressings and topical agents for surgical wounds healing by secondary intention

The best dressing for postoperative wounds healing by secondary intention is unknown.

Decision aids for patients facing a surgical treatment decision: a systematic review and meta-analysis.

Objective:To summarize the evidence available on the effects of decision aids in surgery. Background:When consenting to treatment, few patients adequately understand their treatment options. To help patients make deliberate treatment choices, decision aids provide evidence-based information on the disease, treatment options, and their associated benefits and harms. Although decision aids are not designed to direct patients toward a particular treatment option, it is possible that their introduction will change the proportion of patients that opt for surgery. Methods:We searched electronic databases for studies that evaluated a decision aid in patients offered both surgery and alternative treatment options, regarding the effect on the actual treatment choices made. In addition, we documented effects on knowledge, decisional conflict, anxiety, quality of life, patient involvement, satisfaction, mortality, morbidity, and costs. Results:Seventeen studies were included. Overall, methodological study quality was good. Patients in the decision aid group less often chose to undergo invasive treatment [risk ratio = 0.80; 95% confidence interval, 0.67–0.95), had more knowledge about treatment options [mean difference = 8.99; 95% confidence interval, 3.20–14.78), and experienced less decisional conflict (mean difference = −5.04; 95% confidence interval, −7.10 to −2.99). Levels of anxiety and quality of life were similar. Conclusions:Offering a decision aid increases the number of patients who prefer conservative or less invasive treatment options. As decision aids improve patient knowledge and lower decisional conflict without raising anxiety levels, they have a place in surgery to help surgeons and patients achieve well-considered and shared treatment decisions.

Microcirculatory investigations to determine the effect of spinal cord stimulation for critical leg ischemia: The Dutch Multicenter Randomized Controlled Trial

PURPOSE Patients with non-reconstructable critical limb ischemia generally undergo medical treatment only to prevent or postpone amputation. There is some evidence that spinal cord stimulation (SCS) stimulates ischemic wound healing. Thus, this could benefit limb survival through improved skin perfusion. We investigated the effect of SCS versus conservative treatment on skin microcirculation in relation to treatment outcome in patients with non-reconstructable critical limb ischemia. METHODS Standard medical treatment plus SCS was compared with only standard medical treatment in a multicenter randomized controlled trial comprised of 120 patients with surgically non-reconstructable chronic rest pain or ulceration. We investigated skin microcirculation by means of capillary microscopy, laser Doppler perfusion, and transcutaneous oxygen measurements in the foot. The microcirculatory status just before treatment was classified in three categories (poor, intermediate, and good) and was related to limb survival after a minimum follow-up period of 18 months. RESULTS Clinical parameters, peripheral blood pressures, and limb survival rates showed no significant differences between the SCS and standard groups during the follow-up period. In both treatment groups, amputation frequency after 18 months was high in patients with an initially poor microcirculatory skin perfusion (SCS 80% vs standard treatment 71%; NS) and low in those with a good skin perfusion (29% vs 11 %, respectively; NS). In patients with an intermediate skin microcirculation amputation, frequency was twice as low in patients additionally treated with SCS as in the standard treatment group (48% vs 24%; P =.08). In these patients, microcirculatory reactive hyperemia during the follow-up period reduced in the standard group but not in the SCS group (P <.01). CONCLUSION Selection on the basis of the initial microcirculatory skin perfusion identifies patients in whom SCS can improve local skin perfusion and limb survival.