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Results for “Randomized Response Technic”

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PubMed2002

The metabolic and immune response to laparoscopic versus open liver resection.

BACKGROUND: Laparoscopic liver surgery is a field in its infancy, and scientific evidence of its benefits over those of traditional open techniques has not been shown. Various applications from wedge resections to formal segmental resections have been reported, but the technical ability does not necessarily translate into improved patient outcomes. There is an abundance of evidence reflecting the benefits of laparoscopic cholecystectomy [9, 12, 23], and some of these benefits have been linked to the decreased metabolic and immune responses involved [24, 27]. There is also accumulating evidence that tumor growth may be slower after laparoscopic surgery than after comparable open surgery, and that this is a result of less immune suppression [1]. It is not known whether laparoscopic liver surgery will convey similar benefits. METHODS: In this study, 14 pigs were assigned randomly to undergo a liver resection either by a laparoscopic or an open approach. Operative stress was assessed via cortisol, tumor necrosis factor, interleukin-6, C-reactive protein. The immune response was evaluated through delayed-type hypersensitivity skin antigen testing. Adhesion formation also was assessed at 6 weeks. RESULTS: Immune response as measured by delayed-type hypersensitivity is better preserved after laparoscopic than after open liver resection. The average diameter of induration was 46% greater in the laparoscopic group (20.71 +/- 2.7 mm versus 14.14 +/- 1.5 mm). Interleukin-6 and tumor necrosis factor levels showed a significantly greater rise after open surgery. No difference was observed in the levels of C-reactive protein or cortisol. Adhesion formation was considerably less after laparoscopic resection. CONCLUSIONS: Laparoscopic liver resection results in a diminished stress response, as compared with that of open resection, which translates into greater preservation of immune function. This finding may well have a beneficial effect on infection and tumor growth.

Animals↗

PubMedDate not supplied

Efficacy of radiofrequency procedures for the treatment of spinal pain: a systematic review of randomized clinical trials.

BACKGROUND AND OBJECTIVES: The use of radiofrequency (RF) procedures in the peripheral nervous system to treat chronic spinal pain has been the subject of controversy. Publications concerned only uncontrolled studies, and irreversible nervous tissue damage was believed to be responsible for the effect, if any. In recent years, randomized, controlled studies have appeared, which have attested to an increasing use of these techniques. This is a systematic review of randomized controlled trials on RF procedures for spinal pain. METHODS: We performed a standardized literature search for randomized, controlled trials. Three adjudicators independently registered trial methodology and outcome using validated and subject-related instruments. Interadjudicator disagreement was resolved by discussion. It was found necessary to devise additional parameters of study assessment. RESULTS: Six trials met the inclusion criteria. This small number, along with clinical and technical heterogeneity precluded statistical analysis. All studies, whether high or low quality, reported positive outcomes. CONCLUSIONS: We conclude that there is moderate evidence that RF lumbar facet denervation is more effective for chronic low back pain than placebo. Limited evidence exists for efficacy of RF neurotomy in chronic cervical zygapophyseal joint pain after flexion-extension injury. There is limited evidence that RF heating of the dorsal root ganglion is more effective than placebo in chronic cervicobrachialgia. We recommend the systematic application of our additional parameter assessments for future evaluations of RF studies. These additional parameters should also be used in the preparation of future trial protocols of RF procedures for the treatment of chronic pain.

Humans↗

PubMed2003

Intraperitoneal chemotherapy for ovarian cancer.

Intraperitoneal chemotherapy provides a means by which high concentrations of drugs and long durations of tissue exposure can be attained at the peritoneal surface. It has been studied widely in ovarian cancer, a disease in which intra-abdominal progression remains the major source of morbidity and mortality. Three large randomized trials have shown improved survival in optimally debulked patients who were treated with intraperitoneal chemotherapy as part of a front-line regimen, yet it has not become part of usual therapy. Several factors have contributed to the reluctance to adopt intraperitoneal therapy, including technical issues related to drug delivery and the fact that all of the large randomized trials employed intraperitoneal cisplatin, which has more toxicity than intravenous carboplatin, the current standard of care. Future research is needed for further definition of the clinical benefit of intraperitoneal chemotherapy, modification of existing regimens to minimize side effects, and exploration of intraperitoneal biologic, immunologic, and gene therapy techniques.

Antineoplastic Agents↗

PubMed2001

Comparison of two-level and three-level classifications of moisture-damaged dwellings in relation to health effects.

A total of 630 randomly selected dwellings were surveyed for visible signs of moisture damage by civil engineers, and questionnaire responses were collected from the occupants (a total of 1,017 adults) to analyse the association between moisture damage and occupant health. A three-level grading system was developed, which took into account the number of damage sites in buildings and estimated the severity of the damage. In the present study, this grading system was tested as an improved model of moisture damage-related exposure in comparison to a conventional two-category system: based on independent, technical criteria it also allowed dose-response to be estimated. The questionnaire probed 28 individual health symptoms, based on earlier reported associations with building moisture and mould-related exposure. Criteria in evaluating the goodness of the selected exposure model were (1) dose-responsiveness and (2) higher risk compared to a two-level classification. Dose-responsiveness was observed with the three-level classification in 7, higher risk in 10, and both criteria in 5 out of 28 health symptoms. Two-level classification had higher risk in 4 health symptoms. Dose-dependent risk increases for respiratory infections and lower respiratory symptoms, and recurrent irritative and skin symptoms were observed with the three-level classification using symptom score variables. Although the results did not unambiguously support the three-level model, they underline the importance of developing more accurate exposure models in assessing the severity of moisture damage.

Adult↗

PubMed2005

Randomized clinical trial comparing lightweight composite mesh with polyester or polypropylene mesh for incisional hernia repair.

BACKGROUND: Polymer mesh has been used to repair incisional hernias with lower recurrence rates than suture repair. A new generation of mesh has been developed with reduced polypropylene mass and increased pore size. The aim of this study was to compare standard mesh with new lightweight mesh in patients undergoing incisional hernia repair. METHODS: Patients were randomized to receive lightweight composite mesh, or standard polyester or polypropylene mesh. Outcomes were evaluated at 21 days, 4, 12 and 24 months from patient responses to the Short Form 36 (SF-36) and daily activity questionnaires. Complications and recurrence rates were recorded. RESULTS: A total of 165 patients were included in an intention-to-treat analysis (83 lightweight mesh, 82 standard mesh). Postoperative complication rates were similar. The overall hernia recurrence rate was 17 per cent with the lightweight mesh versus 7 per cent with the standard mesh (P = 0.052). There were no differences in SF-36 physical function scores or daily activities between 21 days and 24 months after surgery. CONCLUSION: The use of the lightweight composite mesh for incisional hernia repair had similar outcomes to polypropylene or polyester mesh with the exception of a non-significant trend towards increased hernia recurrence. The latter may be related to technical factors with regard to the specific placement and fixation requirements of lightweight composite mesh.

Activities of Daily Living↗

PubMed1992

On a common structure of intelligence in biological and technical systems.

This is a survey of the general structure of an electronic computer-implemented, operation-oriented system, designed by the authors, which uses artificial intelligence mechanisms and is intended for the control of technical objects that function both in predictable and random environments. The system is based on processing knowledge, which is stored in a hierarchically arranged Knowledge Bank, and program mechanisms for adapting to and interacting with the External and Internal Worlds. The system has distributed program mechanisms, which are 'designed' with a constant structure. It is independent of the purpose and environment of the system operation and the specific features of the controlled object. None of the program mechanisms are concentrated in any program module. They are distributed in many modules, and therefore there is no single module responsible for the execution of a particular external function. The system is structured into separate program modules by internal procedures. The conceptual organisation of the Knowledge Base presupposes that the framework is structured according to functional, semantic and tier indications, i.e. the structured description of knowledge, by the system, of the external environment and its possible behaviour in it. The possibility of multiple use of the same elements of the lower tiers of the Knowledge Base by higher-tier elements makes the proposed Knowledge Base very efficient. If the cerebrum is considered at a structural level, there appears to be an amazing similarity between the structure and the mechanisms of the above system and the structure of the cerebral cortex, as suggested previously by Edelman and Mountcastle. Each mechanism of the cerebral cortex structure has a structural analogue in the described system.(ABSTRACT TRUNCATED AT 250 WORDS)

Algorithms↗

PubMed1992

The current role of interstitial thermo-radiotherapy.

Internal methods of thermotherapy such as interstitial, endocavitary and perfusional hyperthermia in combination with high- (HDR) or low-dose rate (LDR) brachytherapy have gained increasing interest among oncologists due to the known radio- and chemosensitizing potential of heat. Interstitial techniques offer several advantages over percutaneous heating techniques: confined treatment volume with improved sparing of normal tissue; accessibility of deeper tumors in various sites; more homogeneous distribution of therapeutic temperatures; and better control and evaluation of thermal parameters, when using extensive "thermal mapping" procedures. Currently several promising techniques are investigated such as radiofrequency (RF), microwave (MW) and hot source (HS) techniques. In phase 1 to 2 studies interstitial hyperthermia (IHT) has been mostly applied in the head and neck and brain, the chest wall, the pelvic region and the extremities for primary advanced, persistent or local recurrent tumors, which have responded poorly to conventional treatment approaches. Preliminary data on 600 patients treated with interstitial thermo-radiotherapy (IHT-IRT) are extremely promising despite broad variations among the technical and clinical treatment parameters. The tumor response rate in various clinical trials ranges between 11% and 74% CR, and with respect of extensive pre-treatment approaches, the overall complication rate of 20% appears acceptable. So far several prognostic treatment factors have been identified: tumor volume; radiation dose; high minimum tumor temperatures and sufficiently good thermal quality of the hyperthermia treatment. Future technical innovations should broaden clinical implementations of interventional hyperthermia such as intraoperative hyperthermia and intracavitary hyperthermia. It would appear from these experiences, that interstitial hyperthermia is an effective and safe treatment modality, especially when combined with radiotherapy for tumor palliation. Prospective randomized multicentric studies have already been initiated to investigate its role in palliative and adjuvant tumor therapy.

Brachytherapy↗

PubMed2006

Effect of challenge method on sensitivity, reactivity, and maximal response to methacholine.

BACKGROUND: Recent data suggest that the tidal breathing method may produce methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20) values significantly lower than the dosimeter method; however, the effect of the challenge method on the shape of the concentration-response curve has not been investigated. OBJECTIVE: To determine the effect of the challenge method on sensitivity, reactivity, and maximal response to methacholine. METHODS: We measured airway responsiveness to methacholine using dosimeter and tidal breathing methods in 30 individuals with suspected asthma. Concentration-response curves were characterized by their PC20 (sensitivity), slope (reactivity), and, if possible, level of plateau. RESULTS: Dosimeter PC20 values were significantly higher than tidal breathing values (geometric mean, 8.9 and 5.2 mg/mL, respectively); the mean difference in PC20 values obtained using each method was 0.78 doubling concentrations (P = .01). The mean slopes were 22.7%/log mg/mL using the tidal breathing method and 24.9%/log mg/mL using the dosimeter method; the mean difference in the slopes obtained using each method was -2.17%/log mg/mL (P = .18). In 10 individuals who showed a plateau with the 2 methacholine challenge tests, the mean level of plateau was 19.8% using the tidal breathing method and 19.5% using the dosimeter method; the mean difference in the plateau values obtained with each method was 0.3% (P = .87). CONCLUSIONS: Although the tidal breathing method produces methacholine PC20 values significantly lower than the dosimeter method, both methods provide similar values for slope and level of plateau. These results suggest that the technical factors that affect methacholine sensitivity and the shape of the curve are different.

Administration, Inhalation↗

PubMed1985

Cancer chemotherapy: alternative routes of drug administration. A review.

This review covers recent developments in regional cancer chemotherapy, including the pharmacological background, technical progress, and clinical experience. Intrathecal chemotherapy is an approach that has acquired an established place, although its ultimate potentials are not known yet. The therapeutic value of hepatic intraarterial drug infusion is still unclear, although this route has been used for more than 20 years. Furthermore, the evaluation of alternative routes via the pleural and peritoneal cavities and other arteries is still in an experimental phase. Interest in these treatment modalities has been stimulated by a number of recent developments in separate fields. Major technical advances have been made, including surgically placed and totally implantable elastic catheters and subcutaneous portals and pumps. In addition, a pharmacokinetic model describing the fate of drugs administered via an artery or cavity has been developed. These developments have made it possible not only to design randomized studies and treat a larger number of patients in a relatively short time with reduced morbidity, but also to improve greatly the selection of drugs, target organs, and administration schedules. Ongoing clinical studies can be expected to lead to improved treatment results as well as provide data on dose-response relationships and drug schedule dependency for specific tumor types.

Antineoplastic Agents↗

PubMed1988

The rationale for biochemical monitoring of the fetus.

1. Rates for perinatal mortality and low Apgar scores have not been affected by fetal intensive care (electronic monitoring +/- fetal blood sampling) in any randomized controlled trial to date. 2. Acidosis at birth may be susceptible to improvement by fetal intensive care but has not been tested adequately in more than a few women. 3. Birth asphyxia which is followed by evidence of cerebral dysfunction within the first 48 hours of life can be significantly altered by current technics of fetal intensive care. 4. The evidence suggests that cognitive disorders and cerebral palsy occur as long term sequelae of hypoxic-ischaemic encephalopathy in a small percentage of survivors. However, factors which predate the onset of labour are more likely to be responsible for cerebral palsy than factors associated with labour. 5. Future developments might include the following: (i) To establish that umbilical arterial pH and/or lactate and/or Apgar score is predictive for neonatal outcome such as hypoxic-ischaemic encephalopathy or other markers of asphyxia. (ii) To determine whether umbilical arterial pH and/or lactate is significantly different when continuous biochemical monitoring is used versus traditional intermittent fetal blood sampling, i.e. does continuous monitoring prevent acidosis? In the present state of development of continuous biochemical monitoring technics in labour it seems unlikely that, at the present time, we could answer the larger question of whether such monitoring can prevent the neurological complications of hypoxic-ischaemic encephalopathy and the subsequent developmental problems including cerebral palsy. Finally, we must not forget that labour and delivery represents a relatively small time period in relation to the total duration of pregnancy with a ratio of approximately 1:355. Thus, it is not surprising that many of the problems of neurologic development are difficult to trace back to a particular stage in pregnancy. Careful monitoring of labour and delivery may help to counteract the tendency to blame this period of pregnancy for all subsequent developmental problems of the child.

Apgar Score↗

PubMed2001

Rugby players' satisfaction with custom-fitted mouthguards made with different materials.

OBJECTIVES: This study compared the comfort of two bimaxillary custom-fitted mouthguards. One type was made with silicone rubber and the other with methyl-methacrylate (acrylic). METHODS: The study was a within-subject crossover clinical trial with 52 high-school rugby players who were randomly allocated to one of two groups. The first group wore a silicone mouthguard for 4 months and an acrylic one for the following 4-month period. The second group wore an acrylic mouthguard followed by a silicone one for similar periods. Comfort, bulkiness, stability, hardness, ability to talk and to breathe, oral dryness, nausea and inclination to chew were evaluated for each period using a Visual Analogue Scale questionnaire. RESULTS: There was no significant difference concerning comfort, bulkiness, ability to talk and to breathe, oral dryness and nausea between silicone and acrylic mouthguards by group and time of examination (Three-way ANOVA P>0.05). Acrylic mouthguards were more stable and harder than silicone ones (Wilcoxon's test P<0.01). Tendency to chew was greater for silicone appliances (P<0.01). For stability, hardness and inclination to chew, there was no significant difference in the response of the players based on the sequence of use of the two types of mouthguard during the survey (Mann-Whitney test P>0.05). At the end of the study, 56% of the players preferred to keep the acrylic mouthguard and 44% chose the silicone one. This choice did not vary between the groups (chi2, P>0.05). CONCLUSION: Silicone rubber mouthguards were well accepted by the players but technical improvements in silicone materials are needed to improve hardness and stability of silicone mouthguards for sport.

Acrylic Resins↗

PubMed1996

[Therapeutic intensification and autotransplantation of hematopoietic stem cells in metastatic breast cancers].

The first studies on intensive chemotherapy for metastatic breast cancer conducted in the 80s were disappointing. Despite good response rates, the duration of remission was short and long-term survivals exceptional. Nevertheless, these phase I and II trials helped to develop a better understanding of the potential indications of this new therapeutic approach and apprehend its technical aspects. Over the last 5 years, considerable progress has been made in grafting techniques and hematopoietic support greatly improving the safety of the method. Notwithstanding the financial considerations involved, it must be noted that the efficacy autologous stem cell support, in terms of recurrence-free overall survival, has not yet been demonstrated although the (controversial) results of two randomized controlled trials have recently been published. In France, the PEGASE programs for the study of autologous stem cell support in breast cancer have been developed in an attempt to elucidate the question.

Antineoplastic Agents↗

PubMed2003

Chemoembolization with cisplatin, lipiodol and Gelfoam and subsequent systemic chemotherapy with cisplatin and interferon in patients with hepatocellular carcinoma: a non-randomized prospective study.

Arterial chemoembolization with subsequent systemic chemotherapy was assessed prospectively. Of 94 consecutive patients with HCC, 31 patients were considered to have inoperable disease and were selected for chemoembolization. Twenty-two of the 31 patients underwent chemoembolization. In eight patients, technical problems with catheterization prevented the application of therapy, and one patient rejected further treatment. Regimen: Three monthly cycles of chemoembolization with cisplatin 20 mg/m(2) mixed with lipiodol delivered intraarterially with Gelfoam or collagen on day 1, followed by intravenous chemotherapy with cisplatin 60 mg/m(2) on day 2; interferon alpha-2c 30 microg (10 M IU) subcutaneously on days 2, 5, 9, and 12. Three percent of the patients (1/31) (CI 95% 0.08; 16.7) experienced a partial clinical response, in 53% alpha-fetoprotein levels decreased by more than 50%. On univariate analysis, performance status, Child score, Okuda stage, albumin levels, and lactate dehydrogenase were found to have an effect on survival. Postchemoembolization syndrome occurred in 68% of the patients, nausea/vomiting grades 3/4 (according to the World Health Organization WHO) in six patients, anemia grade 3 in three patients, leukopenia grade 3 in one patient and thrombocytopenia grade 3 in one patient. This treatment regimen is a very selective procedure. Because of the low response rate it is not recommended for routine clinical use.

Adolescent↗

PubMed1985

In vitro assays of chemotherapeutic sensitivity.

The concept of designing an in vitro assay to predict in vivo antineoplastic drug activity that would provide the medical oncologist with the necessary data to define beneficial drug regimens is appropriate; however, the optimal assay has been elusive over the last 3 decades. It is hoped that information gained from attempts to design such an assay has provided further refinements that will bring the goal in reach. The initial studies of drug-induced cell cytotoxicity employing changes in cell metabolism or the cell's ability to exclude supravital dye or reduction in the incorporation of radiolabeled precursors into DNA, RNA, or proteins provided the starting point for developing such an assay. Although initial enthusiasm existed with each of these assays, it soon became apparent that their predictive value was not sufficiently specific to warrant broad application. Modification of the dye exclusion assay or the combination of the clonogenic assay with radio precursor incorporation may provide better predictability. Confirmation of these assays awaits completion of randomized clinical trials. More recently, led by the appreciation of a subset of self-renewing cells--that is, "stem cells" present in the bone marrow--Salmon and colleagues reported on the pertinent applications of the clonogenic assay in predicting in vivo patient responses to chemotherapy. Since this report, considerable advances in development, improvement, and application of the clonogenic assay have occurred. This assay has been applied to preclinical screening of new antineoplastic agents, cytogenetic analysis of human tumor specimens, and the identification of growth factors and hormones for different tumor types. Despite these major advances in applying and solving technical problems associated with the assay, major problems continue to exist, the foremost being the overall poor growth of most tumor specimens in the assay such that in vitro chemosensitivity data can be obtained only in 30% to 40% of specimens. Indeed, because only this fraction grows, it is important to demonstrate that "growth itself" in the assay is not an independent prognostic factor. Further, pharmacologic considerations will have to be completed for each drug such that in vitro studies of drug exposure and drug/drug interaction will mimic the clinical situation. Constant critical analysis of this and other assays will no doubt lead to improvements, particularly their use as tools for biologic studies. Currently, insufficient data on prospective trials evaluating in vitro assays in predicting clinical responses are available.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1978

Efficacy of single-dose and conventional amoxicillin therapy in urinary-tract infection localized by the antibody-coated bacteria technic.

Urine specimens from 61 women with symptoms of cystitis who are infected with amoxicillin-sensitive organisms were examined by the antibody-coated bacteria assay. Patients with negative assays were randomized to receive either a single 3-g oral dose of amoxicillin or 10 days of amoxicillin, 250 mg, given by mouth four times per day (conventional therapy). Patients with positive assays received conventional therapy. All 43 patients without antibody-coated bacteria in the urine, 22 given single-dose therapy and 21 treated conventionally, were cured of their infection. Of 18 patients with antibody-coated bacteria, nine relapsed within one week of completion of conventional therapy. The results of the antibody-coated bacteria assay appear to predict the therapeutic response: both single-dose and conventional amoxicillin therapy are completely successful in patients with negative assays; in contrast, conventional therapy is ineffective in 50 per cent of patients with positive assays.

Administration, Oral↗

PubMed2004

A latent normal distribution model for analysing ordinal responses with applications in meta-analysis.

We consider the comparison of two treatments (or a treatment and a control/placebo) with responses that are classified into ordinal categories. By operating on the assumption that the responses are manifestations of some underlying continuous variables and that the definitions of the categories for the treatment group and the placebo group are the same in the same clinical test centre, we develop a model to examine the possible treatment effects. These treatment effects can be identified as location effect or dispersion effect. The method can be generalized to analyse clinical test results coming from different centres, where each centre may have its own standard in classifying responses. The method is technically undemanding and can be implemented in a very simple and straightforward way by using easily accessible software that can be downloaded at no cost. Real data sets are analysed for illustration.

Alzheimer Disease↗

PubMed1985

Randomised trial of intraperitoneal irrigation with low molecular weight povidone-iodine solution to reduce intra-abdominal infectious complications.

A prospective randomized trial was performed comparing the efficacy of intraperitoneal irrigation with low molecular weight povidone-iodine solution ('Betadine LMW') (PVP-I LMW) in reducing the risk of intra-abdominal infectious complications. Seventy-five patients who were undergoing surgical procedures in the face of bacterial contamination were studied. Patients were intra-operatively randomized to receive intraperitoneal irrigation prior to abdominal closure with PVP-I LMW or with saline. Patients were maintained on peri-operative systemic antibiotics, and surgical incisions were drained and were closed primarily or left open according to the practice of the surgeon responsible. If incisions were closed, the subcutaneous tissue was irrigated prior to skin closure with the same irrigant as used intraperitoneally, PVP-I LMW or saline. Patients were followed for abnormal wound healing, peritonitis, intra-abdominal abscesses, or other infectious complications. Serum iodine levels were monitored in some patients. Intra-abdominal infectious complications developed in two of 37 patients receiving PVP-I LMW irrigation as compared to complications in nine of 38 patients receiving saline irrigation (P less than 0.05). When infectious complications were excluded that were possibly due to surgical technical failures (such as anastomotic leakage), peritonitis or intra-abdominal abscesses were observed in one of 37 PVP-I LMW patients and in seven of 38 saline control patients (P less than 0.05). Wound infections developed in one of 37 PVP-I LMW patients and in three of 38 control patients. A broad range of serum iodine levels were observed in control patients preoperatively and at 24 h and 7 days postoperatively. Serum iodine levels in 'Betadine LMW' patients rose approximately nine-fold by 24 h postoperatively and returned to pre-operative levels by 7 days. It was concluded that PVP-I LMW solution can reduce the incidence of intra-abdominal infectious complications when used as an intraperitoneal irrigant in patients undergoing bacterially-contaminated surgical procedures.

Abdomen↗

PubMed2001

Comparison of two heparin-coated extracorporeal circuits with reduced systemic anticoagulation in routine coronary artery bypass operations.

OBJECTIVES: The use of heparin-coated circuits for cardiopulmonary bypass attenuates the postperfusion inflammatory response. Postoperative bleeding and the need for allogeneic blood transfusions are reduced, particularly in combination with lowered systemic anticoagulation. The two most commonly used heparin-coated systems are the Carmeda BioActive Surface (Medtronic Inc, Minneapolis, Minn) and the Duraflo II coating (Baxter Healthcare Corp, Bentley Laboratories Division, Irvine, Calif). The 2 surfaces are technically unequal, and previous experimental studies have demonstrated disparities in effects on the immune system and the blood cells. However, no larger comparative studies of relevant clinical end points have thus far been reported. METHODS: Over a 24-month period, all patients undergoing coronary artery bypass were prospectively randomized to one of the two heparin-coated circuits. Altogether, 1336 consecutive patients were included. The heparin dose was reduced in all cases, with an activated coagulation time of more than 250 seconds. Clinical data were consecutively collected and stored on a computer for comparative analyses. RESULTS: There were no statistically significant differences in any demographic or operative parameters. The Duraflo II patients required less heparin to keep the target-activated clotting time, confirming the previous finding of some leakage of heparin from the surface to the circulation. Otherwise, there were no significant differences in time for ventilatory support (Duraflo II, 1.7 +/- 1.3 hours; Carmeda BioActive Surface, 1.6 +/- 1.0 hours; P =.37), amount of postoperative mediastinal drainage (Duraflo II, 665 +/- 257 mL; Carmeda BioActive Surface, 688 +/- 243 mL; P =.07), need for allogeneic blood-plasma transfusions (Duraflo II, 4.2% of the patients; Carmeda BioActive Surface, 4.4% of the patients; P =.93), or hemoglobin concentration at hospital discharge (Duraflo II, 120 +/- 13 g/L; Carmeda BioActive Surface, 119 +/- 13 g/L; P =.08). The effects on renal function and platelets were similar, as were the incidences of perioperative myocardial infarction (Duraflo II, 1.5%; Carmeda BioActive Surface, 1.5%; P =.96), stroke (Duraflo II, 1.3%; Carmeda BioActive Surface, 1.2%; P =.47), and hospital mortality (Duraflo II, 1 [0.14%] patient; Carmeda BioActive Surface, 3 [0.45%] patients; P =.31). CONCLUSIONS: Despite differences in technology, complexity, and effects on biologic markers, no clinical differences were observed between the Carmeda BioActive Surface system and the Duraflo II coating after coronary artery bypass operations. The overall clinical results were favorable in both groups, confirming the safety and feasibility of routine use of heparin-coated circuits in combination with reduced systemic anticoagulation.

Anticoagulants↗