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At least 379 records · Page 21Linked to original sources
PubMed1996

Reactions of meniscal tissue after arthroscopic laser application: an in vivo study using five different laser systems.

In many clinical and in vitro studies, the effect of laser radiation on meniscal tissue was examined. Clinical studies referred to clinical criteria like swelling, effusion, and pain to evaluate laser effects. In vitro studies showed the laser effect in the moment of cutting the tissue. But the effect of laser radiation on biological tissue also depends on the vital reaction of the tissue. So, the real extent of tissue damage caused by laser irradiation can only be examined in long-term in vivo studies. This was the purpose of this study. Seventy-two knees of pigs underwent arthroscopic meniscal cuts in the anterior horn of the medial meniscus. The pigs were divided into 6 groups: The first 5 groups were operated with 5 different laser systems: Neodym: YAG 1,440-nm wavelength; Nd:YAG 1,064-nm wavelength, Excimer, Holmium:YAG, and CO2. The sixth group was operated with mechanical punches. From each group, the menisci of the pigs were examined macroscopically and by light-microscope after survival periods of 0, 2, 6, 12 weeks. Results were as follows. (1) All laser systems caused greater damage to the meniscal tissue than mechanical instruments. (2) This damage was a biological reaction of the tissue, characterized by a necrotic zone surrounding the meniscus cut. (3) This necrotic zone was not visible intraoperatively but only 2, 6 and 12 weeks after operation. The diameter of the necrotic zone ranged between 1.5 nm and 9 mm. (4) Meniscus cuts with mechanical instruments showed no necrotic zone in the surrounding tissue. (5) Laser cuts in the meniscus caused more extensive healing reaction than cuts with mechanical instruments. (6) The quality of this healing reaction varied with the different laser systems: the Nd:YAG 1,064-nm, Ho:YAG, and CO2 laser caused only an incomplete healing because the tissue repair showed by tissue growing from the synovial edge into the defect only. The Nd:YAG 1,440-nm wavelength and Excimer led to tissue growing from the synovial edge and to remodeling of original meniscal tissue, recognizable by reduction of the necrotic zone. Arthroscopic surgeons should be aware that the damage to meniscus tissue caused by a laser is much greater than can be seen intraoperatively and is much greater than the damage caused by mechanical punches. The healing reaction of the tissue is more extensive after laser application than after use of mechanical instruments. Results of in vitro studies on the tissue damage caused by lasers are insufficient to describe the whole extent of laser effects on living tissue.

Animals↗
PubMed2003

Ischemic optic neuropathy after endoscopic sinus surgery: a case report.

For the past 2 decades, endoscopic sinus surgery (ESS) has proven effective for treating paranasal sinus disease. Orbital complications of varying degrees, from mild orbital hematoma to catastrophic blindness, have been widely reported. However, defects of the visual field resulting from post-ESS ischemic optic neuropathy (ION) has not to our knowledge been reported in the literature. We were presented with a 51-year-old male patient suffering from loss of sight following an otherwise uneventful ESS. ION is a rare condition, characterized by acute or subacute postoperative loss of sight. The major risks for developing ION include intraoperative anemia, hypotension and systemic illnesses such as hypertension, diabetes or renal failure. Otorhinolaryngologists should be aware that this condition may occur following an uncomplicated ESS procedure, and patients should be given prompt opthalmological consultation when loss of sight is diagnosed postoperatively. Early aggressive and rapid correction of blood pressure and blood transfusions may be helpful in the treatment of patients who develop ION after surgery.

Blindness↗
PubMed2004

Anesthetic strategies for patients undergoing extrapleural pneumonectomy.

Anesthetic management of patients with extrapleural pneumonectomy may contribute to risk reduction, and it differs from management of patients with standard pneumonectomy in several respects. Hemodynamic and intravascular fluid management is complicated by the significantly greater blood loss and impairments of venous return imposed by weighty tumors and the blunt dissection process. There are greater risks of catastrophic (central) bleeding, dysrhythmias, cardiac herniation, and electrocardiographic changes. Restrictive forces increase the likelihood of dependent lung atelectasis during single-lung ventilation. Preoperative assessment of cardiopulmonary reserve remains an imprecise process. Awareness of these risks and limitations enables the anesthesiologist to understand, anticipate, and potentially preempt many intraoperative problems.

Anesthesia↗
PubMed2003

Predicting clinical ischaemia during awake carotid endarterectomy: use of the SJVO2 probe as a guide to selective shunting.

Stroke is a major cause of disability within the western world. About 20% of strokes are a consequence of atheromatous narrowing of the origin of the internal carotid artery. Carotid endarterectomy has been shown to be an effective treatment for those with symptomatic and severe stenosis, provided the risk of death and peri-operative stroke is less than 7%. The aim of this study was to investigate the clinical value of jugular venous oxygen saturation (SJVO2) monitoring in identifying patients who develop cerebral ischaemia whilst undergoing an awake carotid endarterectomy by comparison with a simple neurological assessment. Each patient underwent a standard awake carotid endarterectomy. Peri-operatively a SJVO2 catheter was inserted, and the jugular oxygen saturation was correlated with the presence or absence of cerebral ischaemia. Data from 34 patients were analysed using time-series plots and by calculating a receiver operator characteristic (ROC) curve. The optimal sensitivity and specificity for this technique were found to be 1.0 and 0.8, respectively, when a 25% change in SJVO2 was used as a threshold. Although a small observational study, we have shown that percentage change in SJVO2 correlates well with the development of clinically apparent cerebral ischaemia. This technique may improve the safety of carotid endarterectomy under general anaesthesia when used with other more established monitoring methods.

Awareness↗
PubMed1998

Tramadol or morphine administered during operation: a study of immediate postoperative effects after abdominal hysterectomy.

Tramadol may cause awareness and EEG activation during anaesthesia. We compared tramadol with morphine, administered during wound-closure, surmising that tramadol may cause earlier awakening, more rapid recovery, less respiratory depression and equivalent pain relief. Forty patients received nitrous oxide-enflurane for abdominal surgery. At wound closure, patients received tramadol 3 mg kg-1 or morphine 0.2 mg kg-1 and end-tidal enflurane concentrations were maintained at 0.5 kPa until skin closure, whereupon anaesthesia was discontinued. Times to spontaneous respiration, awakening and orientation were similar in the two groups, as were blood-gas tensions, ventilatory frequency, pain scores and incidence of nausea. Half of each group required supplementary analgesia during their 90-min stay in the recovery room. P-deletion counts improved more rapidly in the tramadol group. This study confirms previous reports that tramadol did not antagonize the hypnotic effects of volatile anaesthetics. Tramadol, administered during operation, was as effective as morphine in providing postoperative analgesia while permitting more rapid psychomotor recovery.

Adult↗
PubMed2004

The Patient State Index as an indicator of the level of hypnosis under general anaesthesia.

BACKGROUND: This retrospective study describes the performance of the Patient State Index (PSI), under standard clinical practice conditions. The PSI is comprised of quantitative features of the EEG (QEEG) that display clear differences between hypnotic states, but consistency across anaesthetic agents within the state. METHODS: The PSI was constructed from a systematic investigation of a database containing QEEG extracted from the analyses of continuous 19 channel EEG recordings obtained in 176 surgical patients. Induction was accomplished with etomidate, propofol, or thiopental. Anaesthesia was maintained by isoflurane, desflurane, or sevoflurane, total i.v. anaesthesia using propofol, or nitrous oxide/narcotics. It was hypothesized that a multivariate algorithm based on such measures of brain state, would vary significantly with changes in hypnotic state. RESULTS: Highly significant differences were found between mean PSI values obtained during the different anaesthetic states selected for study. The relationship between level of awareness and PSI value at different stages of anaesthetic delivery was also evaluated. Regression analysis for prediction of arousal level using PSI was found to be highly significant for the combination of all anaesthetics, and for the individual anaesthetics. CONCLUSIONS: The PSI, based upon derived features of brain electrical activity in the anterior/posterior dimension, significantly co-varies with changes in state under general anaesthesia and can significantly predict the level of arousal in varying stages of anaesthetic delivery.

Adolescent↗
PubMed1988

Peri-operative dreaming and awareness in children.

Dreaming under anaesthesia was investigated in a prospective study of 120 day case paediatric patients, aged 5-17 years, who underwent a variety of surgical procedures. Patients were anaesthetised using the 'Liverpool technique' of paediatric anaesthesia (nitrous oxide-oxygen-relaxant). No patient reported awareness, but 23 of 120 patients (19%) reported dreams. Analysis of the data revealed that the choice of muscle relaxant, (nondepolarising or depolarising) had a statistically significant effect on the incidence of dreaming (p less than 0.05). It is suggested that the technique of intermittent intravenous suxamethonium may result in increased muscle spindle discharge and cause cerebral arousal and an increased incidence of dreaming.

Adolescent↗
PubMed1997

"Gallstone hip" and other sequelae of retained gallstones.

The fate of gallstones spilled during laparoscopic cholecystostomy has been thought to be relatively benign. Recent experience and a review of the recent literature shows that this is not always the case. We report three cases of complications of retained stones and analyse the literature with regard to types of complications, time to presentation, and recommendations for managing spilled gallstones. Retained gallstones have been shown to cause adhesions in the rat and inflammatory reactions in dogs with no evidence of absorption. The average time to presentation of complications arising from retained gallstones is 27.3 weeks. Complications include: Intraabdominal abscess formation with or without abdominal wall sinus tract formation, persisting abdominal wall sinus tracts from port site abscess, subhepatic inflammatory masses, cholelithoptysis, microabscesses and granuloma formation, liver abscess and "dumbell" shaped abscess with one side of the "dumbell" forming a subcutaneous abscess. We recommend the judicious use of retrieval devices during the extraction phase of the laparoscopic cholecystectomy, diligent removal of any spilled stones and awareness of delayed postoperative pain and tenderness as a harbinger of symptomatic retained gallstones. Documentation of intraoperative gallstone spillage, volume, type of gallstones, and effort to retrieve is recommended.

Abdominal Abscess↗
PubMed2005

A comparison of bispectral index and entropy, or how to misinterpret both.

Consciousness monitoring has become increasingly popular in general anesthesia cases, and a new technology has recently been introduced with potential advantages over the other available products. In this case report, we discuss a patient who was monitored simultaneously with Bispectral Index and Entropy and evaluate the differences between the two. More importantly, we emphasize the importance of vigilance when using new technologies and discuss the potential impact of lack of vigilance on patient outcome.

Aged↗
PubMed2003

[Sudden increase in bispectral index during propofol anesthesia in three patients].

We report 3 patients who developed a sudden unpredicted increase in bispectral index (BIS) value during propofol and fentanyl anesthesia. The patients were induced with propofol 2-mg.kg-1 and fentanyl 2-micrograms.kg-1 and muscle relaxation was obtained by vecuronium 0.12-mg.kg-1. During induction of anesthesia, BIS value went down to below 50 in all three cases, and anesthesia was maintained by continuous infusion of propofol at a rate of 5 mg.kg-1.hr-1 and intermittent administration of fentanyl. Forty to sixty min after starting the operation, BIS value increased suddenly (up to 80) and the body movement of the patients was observed. The serum concentration of propofol was approximately 2.5 micrograms.ml-1. All patients were successfully treated with increasing the infusion rate of propofol and additional administration of fentanyl. No clear recall or explicit memory during operation was observed after anesthesia, but, anesthesiologists might have to pay more attention to unpredictable changes of anesthetic depth during propofol anesthesia using target controlled infusion.

Adult↗
PubMed2005

Preventing and managing intraoperative fractures and perforations in hip arthroplasty.

Intraoperative perforation of the femur, a serious complication of hip arthroplasty, encompasses a broad spectrum--from a simple hole in the bone to a displaced fracture with an unstable prosthesis. Although some intraoperative perforations are managed routinely, others are disastrous and often associated with greater morbidity, mortality, increased blood loss, and poor clinical outcome. Appropriate recognition, including an awareness of preoperative risk factors, is paramount to the successful management of these complications. We have found the S-ROM (DePuy Orthopaedics Inc., Warsaw, Ind) prosthesis safe in the prevention of cortical perforation in high-risk patients and effective in managing intraoperative perforation and fracture when it occurs.

Aged, 80 and over↗
PubMed1991

Oxygen-exacerbated bleomycin pulmonary toxicity.

Bleomycin is an antineoplastic agent with potential for producing pulmonary toxicity, attributed in part to its free radical-promoting ability. Clinical and research experiences have suggested that the risk of bleomycin-induced pulmonary injury is increased with the administration of oxygen. We report a case in which the intraoperative administration of oxygen in the setting of previous bleomycin therapy contributed to postoperative ventilatory failure. Our patient recovered with corticosteroid therapy. Physician awareness of a potential interaction between oxygen and bleomycin may help reduce the morbidity and mortality related to bleomycin therapy.

Acute Disease↗
PubMed2000

Minimizing intraoperative recall.

Intraoperative recall has plagued the administration of general anesthesia since the technique was first described, but the media's recent attention to the issue has heightened public awareness and brought it to the forefront of patient concerns. Now, more than ever, patients are asking about the possibility of 'waking up during the operation'. The following review of the literature reveals potential strategies for reducing the risk and managing the sequelae of intraoperative recall.

Journal Article↗
PubMed1980

Surgical management of ruptured abdominal aortic aneurysms.

During a 12 year period ending in 1977, 65 patients had surgical treatment of ruptured abdominal aortic aneurysms. Hospital mortality was 48 per cent (31/65 patients). Preoperative shock (P = 0.05), intraoperative blood loss (P less than 0.01), postoperative respiratory complications (P less than 0.05) and renal failure (P less than 0.05) all significantly influenced early mortality as did multiple subsystem complications (P less than 0.01). Late mortality was 26 per cent, comparable to series of unruptured aortic aneurysm resection survivors. Increased awareness of the problem by physicians, and hence, more aggressive elective treatment of abdominal aortic aneurysms should lower the frequency of this problem, and improved intraoperative and postoperative care should improve survival of those patients whose aneurysms rupture.

Aged↗