Endoscopic surgery and allied technologies最新文献

Laparoscopic procedures with CO2-pneumoperitoneum are used widely in gynaecology and surgery. The effects of a 15 degrees head-down position, different intra-abdominal pressures (IAP) and CO2-insufflation flows on cardiorespiratory parameters were studied prospectively in 18 gyneacologic patients under general anaesthesia. The 15 degrees head-down position led to significant changes in heart rate (-6%) and in central venous pressure (+53%). Furthermore, significant changes under commonly used conditions for gynaecological laparoscopy (IAP 9mmHg, CO2-insufflation flow 2.41/ min., 15 degrees head-down position) were found in heart rate (+16%), systolic blood pressure (+21%), diastolic blood pressure (+26%), central venous pressure (+57%), peak inspiratory pressure (+26%), end-tidal CO2-concentration (+19%), central venous pCO2 (+21%), and central venous pH (-7%). On examination of variable pressure and insufflation flows (IAP 3, 9, and 15mmHg; CO2-insufflation flows 1.2, 2.4, and 6.0 1/min.), increasing changes in heart rate (7% - 24%), diastolic blood pressure (22% - 33%), central venous pressure (30% - 59%) and peak inspiratory pressure (10% - 43%) correlated with increasing IAP. However, they were independent of CO2-insufflation flows. The results demonstrate that CO2-pneumoperitoneum causes marked changes in cardiorespiratory parameters, but these do not exceed levels commonly regarded as safe in ASA class I and II patients.

Laparoscopic closure of perforated peptic ulcer is technically feasible (1). Haemodynamic changes during laparoscopic operations are known and may have an adverse influence on outcome in patients who have peritonitis, are hypovolemic or even septic (2-4). A complete physiological understanding of CO2-inflation of an abdomen in diffuse peritonitis is still missing. The purpose of this study is to compare perioperative variables of general anaesthesia in patients undergoing open or conventional laparoscopic closure of perforated peptic ulcer.

Current medical practice deals with a variety of multimodal information (X-ray film, ultrasound, CT, MR, ECG and EEG, laboratory results, medical records, etc.) Diagnosis and treatment demand an integrated view of this information including the patient's record and history. This paper describes multimodal imaging approaches to such a system with regard to (i) user interface, (ii) data management (including access control), (iii) registration and modality matching based on reference models, and (iv) interface to the modalities.

Laparoscopic cholecystectomy is the standard method for surgical treatment of non-malignant gall bladder disease. Well tolerated in otherwise healthy patients, it remains however, questionable whether the laparoscopic procedure in patients with severe pre-existing morbidity is associated with a higher incidence of negative intraoperative events than open cholecystectomy. Therefore, the incidence of negative intraoperative events was prospectively investigated in a series of 1,367 patients (319 with open cholecystectomy and 1,048 with laparoscopic cholecystectomy) who were analysed for occurrence of events such as hypertension, hypotension, arrhythmia, unusual bleeding and transfusion requirement, regurgitation or aspiration of gastric content and respiratory disorders. For further analysis the patients undergoing each operative procedure were divided into two subgroups with either preoperative ASA physical status I and II or III and IV. The study groups were comparable in sex and age. There were no intraoperative deaths. The frequency of hypertension, hypotension or arrhythmia alone and in combination was similar in both groups. The need for intervention was significantly more frequent in ASA class I/II patients with laparoscopic cholecystectomy. Respiratory disorders were rare. There was a significantly higher incidence of postoperative ventilatory support in patients with conventional cholecystectomy. Transfusion was required significantly less often in patients with laparoscopic cholecystectomy (0.19% versus 15.36%). CO2-pneumoperitoneum led to severe circulatory alterations in 7 healthy patients. The most severe negative event was a cardiac arrest in 1 female patient who was successfully resuscitated without any sequelae. In ASA-class III and IV patients intraoperative negative events were equally frequent and independent of the procedure. Severe preoperative morbidity per se seems to be no contraindication for laparoscopic cholecystectomy.

To support the improvement of advanced laparoscopic surgical procedures, we designed a quantitative analysis method to monitor surgical activities. The emphasis lies on the time spent on these activities and on the instruments controlled by the hands of the surgeon. Our method uses combined video images originating from the laparoscope, an overview CCD camera placed in the operating theatre and, when available, a video colonoscope. After the operation is finished, the images are evaluated by means of a standardised analysis routine based on a spreadsheet program and a set of standard terms (thesaurus), to minimise subjectivity of the analysis. After calculations, the data are presented in tables and graphs, resulting in objective information for research on the operation. Seven advanced laparoscopic procedures, in this case colon resections, have been analysed, and it was demonstrated that the analysis method is capable of describing different laparoscopic procedures using the limited thesaurus. Possible areas of application of the method are the evaluation of time-consuming parts of the operation, of surgical tasks and measurement of the surgeon's learning curve. Other applications are the prediction and measurement of the impact of new instruments and techniques.

The influences of laparoscopic techniques on respiratory function are reviewed according to the published literature. The influences are aroused by the applied pressure and the diffusion and absorption of the gas used. The published incidents of the technique are commented and the necessity of meticulous monitoring of the applied pressure and gas exchange is stressed.

The use of carbon dioxide to create a cavity for the operation of laparoscopic cholecystectomy leads to serious complications of the cardiovascular system; consequently, patients with ischaemic heart disease can be put at greater risk. For example, on reaching an intra-abdominal pressure of 15mmHg, a fall of about 35% of the static compliance was observed. Upon using the Laparolift, these influences on the respiratory system were not detected, and the rise in systemic vascular resistance usually seen with the CO2-pneumoperitoneum did not occur. From the anaesthetist's viewpoint the Laparolift was helpful in the treatment of patients with serious limitations of cardiac function.

The use of computer technology in endoscopic surgery is a necessity if more advanced and high quality minimal invasive operations are to be performed. Since safety and reliability are a major issue in medical applications, the development of computer systems has to follow a systematic procedure including quality assurance and be supervised by project management as employed in such safety-relevant areas as aerospace and nuclear energy. An overview of the early phases of this development process and of the major tests during the process is presented.