PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Autonomous surgery”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources

A comparative study of the clinical effects of oral flunitrazepam, medazepam, and placebo.

In a double-blind randomized study 40 patients received 1 mg flunitrazepam, 40 patients received 10 mg medazepam, and 40 patients received placebo p.o. the night before surgery. On the morning of surgery each patient received another identical oral dose of the product or placebo taken the previous night. On the average, the flunitrazepam group slept better, was better sedated, and was less anxious than the medazepam or placebo groups. Similarly, as a reflection of diminished autonomic reactions, the patients receiving flunitrazepam had fewer cardiovascular changes. Flunitrazepam significantly decreased the amounts of thiopentone needed for induction of anesthesia. Medazepam did not. The pronounced sedative, sleep-inducing, and anxiolytic effects of flunitrazepam appear to be of great clinical importance for its use in anesthesiology. Repeated administrations of medazepam seem to be required to produce an evident clinical effect of the drug, possibly via the slow accumulation of metabolites. The main difference between these two benzodiazepine derivatives as regards clinical response therefore seems to be pharmacokinetic in origin.

Adult↗

[The anesthetic management of Arnold-Chiari malformation with spinal cord injury].

A rare case of spinal cord injury at C3 level associated with Arnold-Chiari malformation is reported. A 33 year old male was admitted with a complaint of walking difficulty. MRI revealed cerebellar herniation, and a plain X-ray showed spinous process adhesion of C2-3 and slight scoliosis. Percent vital capacity was reduced to 69%, and blood cell count showed a slight anemia. The patient was anesthetized for an orthopedic surgery with pethidine 70 mg, thiamylal 200 mg, 60% nitrous oxide, 40% oxide, and 0.5-1.2% isoflurane. There was a mild decrease in arterial blood pressure during surgical procedures, but this could be easily treated by fluid therapy, and there was no episode of autonomic hyperreflexia. Postoperative course of the patient was uneventful, except a transient pneumonia and urinary tract infection. The key in the anesthetic management of Arnold-Chiari malformation with spinal cord injury is the control of intracranial pressure, care for respiratory dysfunction and the prevention of infection as well as autonomic hyperreflexia.

Adult↗

Failure of selective pituitary adenomectomy to cure acromegaly.

Complete selective pituitary adenomectomy for acromegaly may fail to cure the underlying endocrinopathy. A 40-year-old man who had acromegaly of ten-years duration was initially treated with pituitary irradiation eight years prior to surgery. Three years after irradiation his mean GH concentration decreased from 53 to 9.0 ng/ml, then subsequently increased, and was associated with development of severe hyperglycemia. A transsphenoidal microdissection was performed, and a discrete pituitary adenoma was visualized and totally removed at surgery. GH concentrations decreased from 46 to 5.0 ng/ml one week after surgery and to 3.0 ng/ml 10 months after surgery. Despite improvement postoperatively, the patient still demonstrated abnormal GH dynamics and responses to the GTT, abnormal nocturnal and random GH sampling, and abnormal responses to the L-dopa, apomorphine, and TRH stimulation tests. Acromegaly could be caused by either hypothalamic hyperfunction, an autonomous pituitary tumor, or both; but the latter would not explain the results obtained in this patient. This suggests that reduction of GH to normal concentrations following selective pituitary adenomectomy is not synonomous with curing acromegaly.

Acromegaly↗

Autonomous aldosterone-secreting ovarian tumor.

The case of a young woman with primary aldosteronism originating extraadrenally--ovarian tumor--is reported. Clinically she presented with uncontrolled hypertension. Biochemical and hormonal profiles showed features of aldosteronism. The primary was found in the left ovary. Following excision of the tumor, aldosteronism regressed completely. Microscopically, the tumor was of the lipid cell type. Nine months after surgery she is asymptomatic and well. Review of the literature uncovered three previous reports of aldosterone-secreting ovarian tumors.

Adult↗

[Robotics in oral and maxillofacial surgery. Possibilities, chances, risks].

Robot systems are being tested in stereotactic neurosurgical interventions, orthopedic surgery of the hip or knee and advancal endoscopic systems for minimally invasive surgery. In contrast to most industrially manufactured products, objects for medical treatment are characterized by plasticity as well as by complex and individual forms. Thus, features of robots in this field have to be further developed in terms of advanced sensory and specific micromotoric systems. Safety and cooperation between surgeon and robot on the patient in the operating room have to be guaranteed. Extensive three-dimensional diagnosis, computer-aided planning and simulation of the intervention as well as sensory systems that monitor the actual performance of the operation are mandatory parts of this concept. In our interdisciplinary study, we aim to examine whether a robot-given a complete preoperative planning and simulation procedure-is able to perform certain surgical operations more precisely than the surgeon. Examples are drilling with depth control, shaping of bone surface by milling, sawing with defined depth in cranial osteotomies, defined preparation of implant sites and the positioning and insertion of dental and other surgical implants, whereby autonomous employment of the robot is not that which is aspired to in these interventions but rather the interactive support of the surgeon.

Humans↗

Autonomic neural control of cardiac rhythm: the role of autonomic imbalance in the genesis of cardiac dysrhythmia.

Cardiac dysrhythmias result from abnormalities in rate, regularity, or sequence of cardiac activation, and because of direct actions of the autonomic nervous system upon each of these properties, imbalance in this system may play an important role in the genesis of cardiac dysrhythmia. A canine model has been developed in which the extrinsic innervation of the heart is ablated with the exception of the ventrolateral cardiac nerve. This nerve is distributed primarily to the inferior atrial, AV junctional, and ventricular tissues. Following recovery from surgery, the animal is placed on a treadmill and required to perform strenuous exercise. In all of six animals which sustained repeated exercise testing over periods of 4-12 months, dysrhythmias of varying complexities were elicited. None appeared in parallel experiments conducted in control or sham-operated animals. The dysrhythmias consisted of supraventricular, AV junctional, or ventricular tachycardias with occasional premature atrial or ventricular systoles. The dysrhythmias were not influenced by atropine but were generally controlled by propranolol.

Animals↗

Anesthesia, surgical aid and resuscitation in manned space missions.

When discussing problems related to medical service in space flight, particular attention should be given to the specific living conditions and changes associated with space flight. In disease and injury, surgery can be provided only after conservative therapy has failed. In this context gnotobiological chambers allowing surgery in aseptic conditions seem promising. A portable set of interchangeable surgical tools should be made of light-weight alloys that can be readily sterilized. Electroanalgesia in combination with auriculoacupuncture as well as peridureal anesthesia may be used as they allow normal operations in autonomous space flight conditions. Changes in the sympatho-adrenal and kallikrein-kinin systems, as well as water-electrolyte balance, should be taken into account in developing methods and means of medical service in critical situations. Special attention should be given to the prevention and treatment of brain edema in view of weightlessness-induced cephalad fluid shifts.

Aerospace Medicine↗

Observations on physiological and psychological functions of the ventral oral internal nucleus of the human thalamus.

Eight patients underwent VOI thalamotomy for spasmodic torticollis or choreoathetosis. The clinical results were disappointing: at follow-up examination 8 months postoperatively, on average, none of the seven patients with torticollis regarded the effect as good. In two there was some long-lasting improvement, but in five the results was nil. One patient with choreoathetosis did not benefit from surgery. Side-effects were frequent but not serious; they included excessive sleepiness, drowsiness, weight increase, deterioration of memory and loss of general activity. Electrical stimulation of the VOI nucleus caused subjective sensations in the neck and shoulder muscles without movements of the head, and autonomic or emotional reactions. An evoked scalp response was recorded in contralateral frontal area 8. As shown by psychological tests, in visuospatial performances there is a preoperative defect, which seems to be specific to spasmodic torticollis. After left VOI thalamotomy both receptive and expressive verbal efficiency were impaired. Visual perception and memory were almost unaffected by VOI thalamotomy.

Adult↗

Laser surgical treatment of laryngeal paraganglioma.

Paragangliomas are rare benign neoplasms arising from the neural crest-derived paraganglia of the autonomic nervous system. In the larynx three different localizations of paraganglia are known. Most laryngeal paragangliomas arise from the supraglottic paraganglia. A review of the literature shows that the treatment of choice for laryngeal paragangliomas is surgical excision. Since the implementation of CO(2) laser surgery into laryngology in 1972, no reports of endoscopic laser surgical excisions of laryngeal paragangliomas have been published so far. We present the case of a 66-year-old female patient who suffered from a large (4 x 4 x 3 cm) left supraglottic paraganglioma. The tumour was completely excised utilizing the CO(2) laser. Histopathology and immunohistochemistry of the tissue presented the typical findings of a laryngeal paraganglioma. The pre- and post-operative management as well as the treatment strategies are discussed. To our knowledge the present case demonstrates for the first time a complete transoral CO(2) laser surgical resection of an advanced laryngeal paraganglioma.

Aged↗

Sympathovagal effects of spinal anesthesia assessed by heart rate variability analysis.

Heart rate variations (HRV) result from moment-to-moment changes in sympathetic and parasympathetic activity in response to many conditions. These two neural inputs to the heart can be identified by analyzing power spectra of HRV for frequency components at the vasomotor (low-frequency [LF]) and the respiratory (high-frequency [HF]) rhythms. HRV analysis has been used successfully in humans to noninvasively evaluate the autonomic responses to specific maneuvers and drugs, as well as responses to more chronic preexisting pathologic conditions. The effects of an isolated "acute" withdrawal of sympathetic activity in humans, however, have not as yet been evaluated using an autoregressive (AR) technique. We examined HRV using this technique in a group of patients receiving subarachnoid block for abdominal surgery. The sensory levels achieved were within the range of those reported to interrupt sympathetic outflow to the heart. Electrocardiograms were recorded and subjected to AR analysis. AR analysis of HRV after spinal anesthesia revealed significant decreases in both dominant frequency components (LF and HF) that occur between 0.03 Hz and 0.5 Hz. These reductions coincided with blockade of cardiac sympathetic outflow after cephalad spread of the spinal block. The power spectra were almost abolished in patients with sensory blocks reaching T1-2. The decreases in amplitude of the LF and HF components, therefore, act as markers of diminished sympathetic and parasympathetic activity to the heart, while the ratio of LF:HF indicated that sympathovagal balance was predominantly maintained during most of the block.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Spinal↗

Current status of total mesorectal excision and autonomic nerve preservation in rectal cancer.

Two decades have passed since the late 1970s, which witnessed the introduction of total mesorectal excision (TME)-based operations for rectal cancers on both sides of the Atlantic. Since the introduction of TME, clinical experience has been reported widely in the form of single- and multisurgeon reports from wide geographic regions with multiple participants, and from specialty services with narrow focus and high levels of expertise. All of these published results conclude that in comparison with conventionally practiced blunt surgery for rectal cancer, TME-based (i.e., anatomically correct, sharply performed) operations are associated with significantly lower rates of pelvic (local) recurrences, a significantly higher rate of survival, and significantly lower long-term morbidity. The latter is accomplished through dramatically higher rates of sphincter preservation, and the preservation of both sexual and urinary functions. Overall, there is a remarkable similarity in the clinical results that have been reported from diverse centers. TME now forms the basis of large randomized clinical trials in which the role of adjuvant therapy is being reexamined. The current status of TME is reviewed, and the authors' clinical results of a consecutive series of 544 TME-based operations performed through 1998 are updated.

Autonomic Pathways↗

Total and partial cardiac sympathetic denervation after surgical repair of ascending aortic aneurysm.

UNLABELLED: Sympathetic cardiopulmonary nerves arise from the cervical sympathetic trunks and travel alongside the great arteries to innervate the ventricles. Because of the proximity of the nerve and artery, cardiac sympathetic denervation may occur in patients who have just undergone surgery for the repair of an ascending aortic aneurysm. METHODS: To evaluate the cardiac sympathetic activity in aortic aneurysm, we performed cardiac 123I-metaiodobenzylguanidine (MIBG) imaging on 12 patients (mean age +/- SD, 47 +/- 17 y) before and after the surgical repair of an aneurysm. Seven patients scheduled for coronary artery bypass grafting also underwent 123I-MIBG imaging as controls for open-chest surgery. Planar images were obtained at 15 min (early) and 4 h (delayed) after injection of 111 MBq 123I-MIBG, and the cardiac 123I-MIBG uptake was graded quantitatively and visually. The quantitative evaluation was based on the heart-to-mediastinum ratio (H/M), and visual evaluation was performed by assigning a score of 0-3 (0 = absent, 1 = severely reduced, 2 = reduced, and 3 = normal). Heart rate variability using 24-h Holter electrocardiography was analyzed before and after the operation to generate a time-domain index of heart rate variability as an index of autonomic balance. RESULTS: In patients with aortic aneurysms, both early and delayed H/Ms were significantly decreased after the operation (early H/M: 1.84 +/- 0.16 before vs. 1.40 +/- 0.16 after, P = 0.001; delayed H/M: 1.79 +/- 0.38 before vs. 1.27 +/- 0.18 after, P = 0.004). Visual analysis of 123I-MIBG accumulation in early images showed absence of 123I-MIBG accumulation in 3 of 12 patients, a score of 1 in 7 patients, and a score of 2 in 2 patients. In contrast, no significant difference between H/M before surgery and H/M after surgery was seen in patients who underwent coronary artery bypass grafting. The time-domain index of heart rate variability was significantly lower after the operation than before (135 +/- 40 after vs. 96 +/- 27 before, P < 0.05). CONCLUSION: Cardiac sympathetic nerves are totally or partially denervated after the surgical repair of ascending aortic aneurysm.

3-Iodobenzylguanidine↗

Robot-assisted craniotomy.

In the Special Research Centre 414 of the German Research Funding (DFG, Bonn) a system for robot-assisted cranial surgery was developed. It is designed for the accurate and safe execution of craniotomies and repositioning of bone pieces. The system is intended for use in the surgical therapy of craniosynostosis. Preoperatively, CT imaging is performed. In a computerized planning system the position and shape of the intended craniotomy is intuitively planned on a virtual model of the patient's skull. Intraoperatively, after conventional removal of the covering soft tissue, the robot performs the craniotomy autonomously. Extensive testing in phantom studies and animal tests confirmed the reliability and accuracy of the system. A thorough risk analysis of the system was performed. In this paper, the first clinical use of the system on a patient is described and the clinical importance is discussed.

Bone Cysts↗

Severe orthostatic hypotension following weight reduction surgery.

Surgical interventions for morbid obesity are common practice in many countries, especially when other treatment options have failed or when rapid weight loss is desired. The association between weight and blood pressure is well established, especially the paradigm of obesity-related hypertension. We describe a 45-year-old obese woman with a medical history of hypertension and type 2 diabetes mellitus who lost 57 kg within a few months after a weight reduction surgery. She suffered from severe orthostatic hypotension, which probably resulted from sympathetic nervous system dysfunction. Our patient's clinical status improved with pharmacological interventions, but her symptoms resolved completely after she gained weight following a surgical reversal of the gastric partitioning owing to a local complication. Autonomic nervous system activity does change with the changes in body weight, but after evaluation of this patient, we believe that rapid weight loss may impair sympathetic function and blood pressure control. Although losing weight is a known treatment option for hypertension, exaggerated reversal of obesity-related hypertension might result in orthostatic hypotension.

Combined Modality Therapy↗

Post-survey follow-up for human cystic echinococcosis in northwest China.

In Hobukesar, Xinjiang Uygur Autonomous Region, (China), a mass-screening programme for human cystic echinococcosis (CE)was performed during 1995 and 1996. After the survey 51 cases were followed-up using ultrasound scan and serology for 1-8 years(1996-2003). These included 20 CE cases treated by surgery (endocystectomy), four CE cases treated by percutaneous drainage(PAIR), six untreated CE cases, five ultrasound 'query' cases, eight cases of isolated hepatic calcifications, four previous CE surgery cases whose ultrasound was now normal, and four seropositive cases who exhibited a normal hepatic ultrasound. Follow-up results indicated that in the untreated CE patients, one case exhibited a spontaneous cure within 4 years, another case changed from a hepatic hydatid cyst that contained a floating laminated membrane (type CE3) to a cyst that contained daughter cysts (type CE2)within 1 year of follow-up. In the 20 surgically treated cases, two recurrent CE cases occurred within 4 years, and five cases had had residual cavities for more than 4 or 8 years. Of the 4 PAIR treated cases, two recurrent cases of CE occurred within 4 or 8 years of follow-up. Serological follow-up data showed that specific IgG antibody levels were persistently positive in most CE cases, but exhibited a decreasing tendency in cases that were effectively treated by surgery; In contrast, serum IgG levels in the PAIR group or in the recurrent CE cases after surgery exhibited an increasing tendency. At least one persistent seropositive case with an isolated hepatic calcification was considered to be abortive CE.

Albendazole↗

Clinical review of beta-blockers in anxiety.

Anxiety has three essential elements: the subjective experience, autonomic symptoms and avoidance behaviour. Various theories are considered which highlight the psychic and somatic aspects of anxiety. Beta-adrenergic receptor blocking drugs have been used with advantage to treat everyday stresses. These include the anxiety produced by the civil disturbances in Northern Ireland, performing surgery, dentistry, musical instruments or speaking in public, as well as examination nerves. The profile of symptoms such as tachycardia, palpitations and tremor which are most likely to respond to beta-blockers are discussed as well as their side-effects. Their mode of action is different from other anxiolytics, with which they can be combined.

Adrenergic beta-Antagonists↗

Treatment of neuroblastoma in patients with neurocristopathy syndromes.

Neuroblastoma, a neoplasm of neural crest cell origin, occasionally presents in association with other neural crest abnormalities such as Hirschsprung disease, congenital central hypoventilation, autonomic disturbances, and other tumors. These associations have been termed "neurocristopathy syndromes." In the past, chemotherapy has not been considered for patients with neurocristopathy-associated neuroblastoma because of their complicated medical problems. The authors describe two patients with neurocristopathy syndromes from our institution who underwent surgery and standard chemotherapy treatment of their intermediate-risk neuroblastoma. They represent two of only three long-term disease-free survivors of neurocristopathy-associated neuroblastoma reported in the literature.

Abnormalities, Multiple↗

Thyroid tissue: US-guided percutaneous interstitial laser ablation-a feasibility study.

PURPOSE: To evaluate percutaneous interstitial laser photocoagulation (ILP) as a palliative treatment of recurrent thyroid carcinoma untreatable with surgery or radioiodine administration. MATERIALS AND METHODS: By using 18 resected thyroid glands, the volume and histologic pattern of ILP-induced thyroid damage were assessed. In vivo treatment feasibility was evaluated by using a low-energy laser in two volunteers before thyroidectomy for huge autonomously functioning nodules. With ultrasonographic (US) monitoring, a 21-gauge spinal needle was inserted into the thyroid nodules. A 300-microm quartz fiberoptic guide was inserted through the needle lumen, and the fiber tip was placed in direct contact with the tissue. Laser irradiation was performed with a 1.064-nm Nd:YAG laser in surgically resected glands, which were treated with 2, 3, 5, or 7 W. RESULTS: Tissue ablation was well-defined histologically, and its area was related to laser irradiation parameters (range, 0-26 mm). No correlation was found between US images and the actual extent of laser-induced lesions. Large colloid or fluid collections did not permit regular heat diffusion within the tissue. In vivo low-energy ILP was performed without technical difficulties or complications. CONCLUSION: ILP induces well-defined tissue ablation correlated with energy parameters in thyroid glands devoid of cystic areas. ILP could be a therapeutic tool for highly selected problems in thyroid tumor treatment.

Analysis of Variance↗