{"title":"Principles of development and design of microsystems.","authors":"B Wagner","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The state of the art in microsystem design and fabrication is reviewed. The focus is on silicon micromachining, which uses the equipment and processes of IC-technology to produce highly miniaturized, three-dimensional structures, sensors and actuators for various biomedical applications. The micro components can be integrated into surgical instruments, catheters and implants. Thus new functions and a higher level of intelligence are created. Portable microsystems are being developed for chemical analysis and biomedical monitoring. The cultivation and investigation of live cells on chip substrates offers encouraging perspectives for the future.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 4","pages":"204-9"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19814226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Haemodynamic changes during laparoscopic cholecystectomy in the high-risk patient.","authors":"R Stuttmann, C Vogt, E Eypasch, M Doehn","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Although laparoscopic cholecystectomy (LC) has become the standard surgical procedure for the treatment of gall stones, the question has still to be answered whether it is safe for critically ill patients with cardiac disease. 20 ASA-class III/IV patients were monitored during LC by means of a Swan-Ganz catheter. Commencement of anaesthesia led to a significant decrease of mean arterial pressure, cardiac index, stroke volume index and left ventricular stroke work index. Increasing intra-abdominal pressure by insufflation of CO2 and surgical stimuli during gall bladder dissection induced an increase of pulmonary arterial occlusion pressure mean pulmonary artery pressure and central venous pressure (p = 0.05). Mean arterial pressure, cardiac index, stroke volume index and left ventricular stroke work index remained below pre-induction values (p < 0.05). In 13 patients with high filling pressures the administration of nitroglycerine improved all parameters. In the post-anaesthetic care unit all parameters had returned towards baseline. In conclusion, LC may lead to temporary myocardial insufficiency. Nevertheless, LC seems to be safe provided that pathological alterations are recognised and treated.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 4","pages":"174-9"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19814220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Helium insufflation in laparoscopic surgery.","authors":"G P Naude, F S Bongard","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Carbon dioxide is the most commonly used gas for abdominal insufflation in laparoscopy today. Due to the solubility of carbon dioxide large volumes are absorbed into the circulation causing a high PCO2 and a low pH (respiratory acidosis). Carbon dioxide is also stored in several sites in the body and is released at the conclusion of the procedure prolonging the respiratory acidosis when the patient is least able to cope with this additional burden. Cardiac effects of CO2 consist of a lowering of the arrhythmia threshold, increased blood pressure, pulse and cardiac output. At a sustained high level this can lead to cardiac depression and death. These effects are particularly prone to occur in cardiac and respiratory cripples. Other gases that have been used include air, oxygen, nitrous oxide and nitrogen. Their use has been discontinued because of the danger of embolism. Air, oxygen and nitrous oxide are also not safe to use in the presence of electrosurgical instruments thereby limiting their usefulness even further. Helium has been proposed as a very promising alternative to CO2. In the laboratory and in a clinical trial, helium has not produced the respiratory acidosis associated with CO2 insufflation. This is further evidence that the acidosis is not primarily due to elevation of the diaphragm and consequent increased dead space, but to the large amount of CO2 that is absorbed directly from the peritoneal cavity. Helium would seem to be the gas of choice at this time as it comes close to fitting the criteria for an ideal insufflating gas. Helium is clear and colorless, allowing unimpeded vision to the operator. It is non toxic, not flammable or explosive and can be safely used with electrocautery and laser. Helium is easy to handle and not very soluble which decreases the amount absorbed from the peritoneal cavity and consequently the amount used. That which is absorbed is quickly cleared by the lungs. Helium is metabolically inactive (in contrast to CO2) and does not interfere with normal metabolic processes. In view of this promising initial work, further studies are indicated.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 4","pages":"183-6"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19814222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"OREST II--ergonomic workplace and systems platform for endoscopic technologies.","authors":"M O Schurr, G Buess","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Endoscopic interventions require a multitude of technical devices, like gas-insufflators, cameras, light sources, high-frequency scalpels and others. The devices available today represent stand-alone \"function-insulas\" from the view-point of systems technique. They have to be placed in the operating theatre and set-up right before each specific intervention. From each of these single devices supplies, cables and hoses lead to the body of the patient and have to be connected on both sides within the sterile and the non-sterile field. This not only requires a long setup time in the OR but also restricts the mobility of the operative personnel. Besides the ergonomic and the hygienic weakness of the contemporary solution, significant functional problems limit the efficiency of the OR environment. One of the major drawbacks lies in the lack of direct control of the devices by the surgeon and the confusing display of parameters and technical status. Against this background the systematic revision of the current endo-surgical workplace appears to be a major requirement for further technical and surgical progress. As a result of close cooperation between surgeons and engineers a systems workplace for minimally invasive surgery, OREST, has been developed and clinically tested. It integrates all devices into a mobile cabinet. The single devices are connected to a central computer and can be remote controlled directly by the surgeon from the table. A special display continuously informs about the system status. The lines and cables are guided into the sterile field by means of a swivel arm from one side of the patient. Multi-plugs are used to connect all lines at a central terminal within the sterile area. Clinical application of the first prototype OREST I started in 1993. OREST II is now available as a series product. Further development is focused on the integration of advanced sub-systems like tactile devices and advanced vision system.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 4","pages":"193-8"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19814224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Disposable and reusable trocars.","authors":"D I Watson","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A wide variety of disposable and reusable trocars have been designed and marketed for use in laparoscopic surgery. The performance of these instruments varies considerably. Disposable trocars usually contain valve designs which allow the easy passage of instrumentation and safety mechanisms which reduce the likelihood of visceral injury from the trocar point. Whilst most reusable trocars have not provided safety mechanisms, and have been less user-friendly, newer designs are beginning to bridge the gap. The choice of a trocar for laparoscopic surgery will depend on each surgeon's perception of the advantages and disadvantages of competing instrumentation, which may need to be balanced against the budgetary requirements of their practice location.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"140-2"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18557003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Endoscopic capsulotomy by means of laser--a new therapeutic method in cases of capsular contracture.","authors":"U Herrmann","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The laser endoscopic capsular technique is a new method introduced to treat patients who develop capsular contracture after the insertion of a breast prosthesis. A capsuloscope was developed in co-operation with M. Boebel (Richard Wolf) to undertake the procedure. Twenty patients have undergone 25 capsulotomies. The technique relieved pain, corrected the deformity and reduced hardness.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"112-4"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18560348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Reusable, re-posable and disposable instrumentation.","authors":"A Melzer, G Buess","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"127-8"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18560352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The evolving design of laparoscopic instruments.","authors":"G G Stenning","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Due to the rapid acceptance of new laparoscopic techniques, older instruments have been directly adapted to new purposes. The new laparoscopic applications and the evolution of these techniques have led to specific new designs. In this paper the evolution of laparoscopic instruments towards better safety standards with regard to sterility is examined. It is found that although the problem of sterility can be solved, this comes at an increased cost.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"133-4"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18557005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Disposable versus reusable instruments in laparoscopic cholecystectomy. A prospective, randomised study.","authors":"V Paolucci, B Schaeff, C N Gutt, A Encke","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We quantified and compared the advantages and disadvantages of disposable and reusable laparoscopic instruments in a prospective, randomised study of 158 cholecystectomies. The patients were randomly divided into two groups: 80 underwent surgery with reusable instruments, 78 with disposable instruments. The following parameters were recorded in both groups: duration of surgery, number of complications, technical problems during surgery, rate of conversion to open surgery, subjective postoperative pain, postoperative hospitalisation time, length of inability to work, and postoperative evaluation by the operating room personnel. No overall differences were found in subjective pain, postoperative complications, postoperative hospitalisation time, or time before returning to work. Surgery with disposable instruments was on the whole faster, with fewer conversions to open surgery, but this was statistically non-significant. Reusable instruments were associated with a statistically significant increase in the rate of intraoperative, instrument-related difficulties. In spite of longer operation times and higher personnel costs with reusable instruments, we found that cholecystectomy with reusable instruments costs an average of 1,015 DM less per procedure.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"147-50"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18557006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nursing aspects of gynaecologic endoscopy.","authors":"W K Winer","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Nurses now play an integral part in gynaecological endoscopic surgery, with the video camera enabling the operating room staff to visualise the entire procedure. Endoscopy teams are being developed in the operating room for specialised procedures to ensure that nurses assisting with such procedures are familiar with the endoscopic surgeon's routine, instrumentation and equipment. The team consists of the surgeon, surgical assistant, scrub technician, circulating nurse and laser nurse.</p>","PeriodicalId":79337,"journal":{"name":"Endoscopic surgery and allied technologies","volume":"3 2-3","pages":"109-11"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18560347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}