PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Intraoperative Awareness”

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 469 records · Page 26Linked to original sources
PubMed1987

Myocardial ischemia during cardiovascular surgery as detected by an ST segment trend monitoring system.

The incidence of intraoperative myocardial ischemia was determined in 312 patients undergoing cardiovascular surgery using ECG recordings obtained from a prototype system that trends ST segment changes. Prior to cardiopulmonary bypass, ischemic ECG changes were observed in 11.9% of patients, the incidence being lower during coronary artery bypass grafting (CABG) procedures (8.1%) than in patients undergoing repeated CABG (23.5%), valve replacement (25.9%), or concomitant valve replacement and CABG (35.3%). The occurrence of intraoperative myocardial ischemia was statistically greater in patients with a history of hypertension, two or more previous myocardial infarctions, or kidney disease. The incidence of ischemia was also significantly greater in patients with left ventricular end-diastolic pressures of 15 mm Hg or higher at cardiac catheterization. The incidence during induction was significantly reduced by the addition of hypnotics to narcotics, and, during maintenance, by the addition of an inhalational agent. The majority of ischemic events were temporally related to some hemodynamic disturbance, and many coincided with surgical manipulation. The incidence of intraoperative myocardial ischemia was substantially less than that reported in comparable studies. Since the incidence decreased significantly following clinical acceptance of the prototype system, the authors conclude that such capability increases sensitivity to small ST segment changes. This heightened awareness and prompt remedial action reduced the incidence of ischemia during CABG to 6% during the final 2 years of the study.

Aged↗
PubMed1994

[Capnothorax and subcutaneous emphysema in attempted laparoscopic suture of duodenal ulcer].

A 72-year old lady suffering from coronary heart disease was admitted with acute abdominal pain. Laparoscopy was performed and revealed perforation of a duodenal ulcer. The surgeon decided to suture the perforation via laparoscope. After an uncomplicated start he had to finish the laparoscopic procedure because of a massive hypercapnia and a developing subcutaneous emphysema. Laparotomy showed an iatrogenic perforation of the right diaphragm. A chest drain was inserted; after suturing of the perforated ulcer the abdomen was closed. The further hospital stay was uneventful. The possible causes for the increasing hypercapnia are discussed. We suggest close monitoring of patients during laparoscopy including capnometry and the anaesthesist should be aware of rare complications.

Aged↗
PubMed1989

Perioperative care of the liver transplant patient.

1. Communication among team members on the liver transplant team is crucial; individual responsibilities must be considered while problem solving is shared as a team. 2. A major goal of the OR nurse is to maintain the patient's skin integrity; proper patient positioning and protection is essential. 3. Constant awareness of blood and blood product availability is urgent.

Humans↗
PubMed2003

Visual perception during phacoemulsification cataract surgery under topical and regional anaesthesia.

PURPOSE: To compare the subjective visual experiences of patients during phacoemulsification and intraocular lens (IOL) implantation using regional and topical anaesthesia. DESIGN: A prospective, cohort, questionnaire-based study. METHODS: The study cohort consisted of 247 patients without pre-existing ocular pathology who underwent routine phacoemulsification and IOL implantation. The mean age of the subjects was 75.4 +/- 9.4 years and 34.5% of them had a history of cataract surgery. Three different methods of local anaesthesia were used: 66 (26.7%) of the patients were given topical anaesthesia (TA); 74 (30.0%) were given sub-Tenon's anaesthesia (SA), and 107(43.3%) were given peribulbar anaesthesia (PA). The patients were interviewed immediately after surgery by theatre staff using a standardized questionnaire that investigated their intraoperative visual experiences. RESULTS: There was no significant difference between the three methods of anaesthesia regarding light perception during the surgery. However, patients undergoing surgery under TA experienced brighter light intensity levels (78.3%) than those given SA (50.0%) and PA (55.7%) (p = 0.02). A total of 69.6% of subjects who received TA reported visual perception of colours during surgery, as opposed to 56.8% of SA recipients and 49.0% of PA recipients (p = 0.02). In addition, patients under TA were more aware of surgical instruments (26.1%) than those under SA (10.8%) and PA (15.9%) (p = 0.08). The vast majority of patients in all three groups found the visual experience to be non-frightening. There were no associations between intraoperative visual impression and age or sex. Although not statistically significant (p = 0.06), prior cataract surgery appeared to alleviate some of the anxiety associated with the visual experience. CONCLUSION: Patients undergoing regional and topical anaesthesia experience a wide variety of visual sensations during surgery. The differences in visual impressions between the groups may reflect the varying degrees of optic nerve blockade that result from the different anaesthetics.

Aged↗
PubMed1983

Unusual and fatal complications of rhinoplasty.

Serious complications of cosmetic rhinoplasty are extremely rare. However, awareness of their existence is essential so that the surgeon can minimize the potential hazards of the procedure. This demands a careful preoperative examination, a meticulous intraoperative technique, and a careful postoperative monitoring of the patient. The complications of rhinoplasty have been classified into infectious, traumatic, hemorrhagic, systemic, and miscellaneous groups. The pertinent literature is reviewed, as well as cases of inclusion cyst formation, disturbance of eye closure, local activation of systemic disease, and fatalities from intracranial injury with brain laceration and pneumocephalus.

Adolescent↗
PubMed2006

Acute exacerbation of interstitial pneumonia following surgical lung biopsy.

STUDY OBJECTIVES: Surgical lung biopsy (SLB) plays an important role in the diagnosis of interstitial pneumonia, however, the occurrence of acute respiratory failure following SLB remains largely unreported. We evaluated the incidence, clinical features, therapy and prognosis of acute exacerbation of interstitial pneumonia following SLB. DESIGN: Retrospective study of consecutive patients who underwent SLB to establish a diagnosis of diffuse lung disease between May 1989 and April 2000. Patients with an acute exacerbation following lung biopsy were studied, and the HRCT images of the chest before and after surgery were reviewed. MEASUREMENTS AND RESULTS: Among the 236 consecutive patients with interstitial pneumonia who underwent a surgical lung biopsy, five (2.1%) (IPF, 3; NSIP, 1; COP, 1) developed acute exacerbation of the diffuse lung disease in the course of 1-18 days after SLB. The extent of parenchymal involvement on HRCT before surgery was not significantly different between operated and contralateral nonoperated lung. Significantly increased regions of parenchymal involvement on HRCT were seen postoperatively compared with the preoperative CT in both the operated (20.7+/-12.5% versus 38.2+/-10.8%, P = 0.0431) and nonoperated lung (22.7+/-13.8% versus 70.5+/-24.4%, P = 0.0431), but the extent of the parenchymal involvement was significantly greater on the nonoperated side (P = 0.0251). Two of the 3 IPF patients died from the acute exacerbation. CONCLUSIONS: It is important to be aware of the possibility of acute exacerbation of interstitial pneumonia following SLB even after an apparently uneventful immediate postoperative course. The asymmetric image findings suggest that intraoperative respiratory management is a possible etiologic factor.

Acute Disease↗
PubMed1990

Renal vein anatomy and its implications for retroperitoneal surgery.

Because of its complicated embryological development, the anatomy of the renal veins shows extensive variability. A full understanding of the potential anatomical variations is imperative for retroperitoneal operations. Based on 4,520 retroperitoneal computerized tomography scans, anatomical studies of autopsy material of 354 unselected cases and intraoperative observations made during 215 major retroperitoneal procedures, an attempt was made to define the most common renal vein variants and retrace their development during embryogenesis. Awareness of rare anomalies in urological and general surgery is crucial to prevent severe damage to the venous drainage of the left kidney, and because troublesome bleeding may occur during vascular and retroperitoneal oncological procedures in patients with unknown venous anomalies. We found the incidence of these variants to be 0.8 versus 1.7 versus 3.7%, respectively.

Humans↗
PubMed1999

Hemispheric-synchronisation during anaesthesia: a double-blind randomised trial using audiotapes for intra-operative nociception control.

The possible antinociceptive effect of hemispheric-synchronised sounds, classical music and blank tape were investigated in patients undergoing surgery under general anaesthesia. The study was performed on 76 patients, ASA 1 or 2, aged 18-75 years using a double-blind randomised design. Each of the three tapes was allocated to the patients according to a computer-generated random number table. General anaesthesia was standardised and consisted of propofol, nitrous oxide 66%/oxygen 33%, isoflurane and fentanyl. Patients breathed spontaneously through a laryngeal mask and the end-tidal isoflurane concentration was maintained near to its minimum alveolar concentration value of 1.2%. Fentanyl was given intravenously sufficient to keep the intra-operative heart rate and arterial blood pressure within 20% of pre-operative baseline values and the fentanyl requirements were used as a measure of nociception control. Patients to whom hemispheric-synchronised sounds were played under general anaesthesia required significantly less fentanyl compared with patients listening to classical music or blank tape (mean values: 28 microgram, 124 microgram and 126 microg, respectively) (p < 0.001). This difference remained significant when regression analysis was used to control for the effects of age and sex.

Acoustic Stimulation↗
PubMed2006

The Narcotrend 'depth of anaesthesia' monitor cannot reliably detect consciousness during general anaesthesia: an investigation using the isolated forearm technique.

BACKGROUND: During general anaesthesia in the presence of neuromuscular blocking drugs clinical criteria cannot detect the presence of consciousness. Various 'depth of anaesthesia' monitors are available which claim to prevent consciousness and/or reduce anaesthetic drug use. This study uses the Narcotrend anaesthesia brain monitor to guide anaesthetic administration but at the same time checks for the presence of intra-operative consciousness by using the 'isolated forearm' technique throughout the whole surgical/anaesthetic procedure. METHODS: Twelve women presenting for major gynaecological surgery under general anaesthesia, which included the use of neuromuscular blocking drugs, had a target controlled infusion of propofol adjusted according to the anaesthetic 'stage' indicated by a Narcotrend 'Depth of Anaesthesia Monitor'. Throughout surgery the isolated forearm technique was used to detect for the presence of consciousness at 1 min intervals. RESULTS: Isolated forearm responses to commands occurred in all 12 patients at some time during surgery, frequently in the absence of any significant changes in the usually monitored clinical variables. Overall, the 12 patients responded a total of 92 times during surgery. Only 41 (45%) responses were associated with an increase in the Narcotrend stage to a level suggesting consciousness (above stage C(0)). For the remaining responses, either there was no significant increase in the Narcotrend stage (above C(0)) or there was no change at all in the Narcotrend stage before, during, or after the patient responded to the taped command. CONCLUSIONS: The Narcotrend was unable to differentiate reliably between conscious and unconscious patients during general anaesthesia when neuromuscular blocking agents were used.

Acoustic Stimulation↗
PubMed2004

Intra-operative mapping of cortical areas involved in reading in mono- and bilingual patients.

In order to identify the cortical areas involved in the reading process and to spare them during surgery, we systematically studied cortical areas by direct cortical stimulation in patients operated on for brain tumours. Seventy-six cortical stimulation mapping studies for language were performed in 35 monolingual and 19 bi- or multilingual patients over a 5-year period. We systematically searched for reading interference areas in addition to standard naming areas using an 'awake surgery' technique for brain mapping. A 'reading aloud' task (translated into different languages in multilingual patients) was used. Brain mapping was performed in left (44 patients) and right (10 patients) hemispheres. Cortical areas involved in reading were identified according to the type of interference, location and distinctness from naming areas. Stimulation of several major hemispheric regions resulted in significant interference with reading aloud: (i) the lower part of the pre- and postcentral gyri (P < 0.00001); (ii) the dominant supramarginal, angular and the posterior part of the superior temporal gyri (P < 0.00001); (iii) in the dominant inferior and middle frontal gyri (P < 0.001); and (iv) in the posterior part of the dominant middle temporal gyrus (P < 0.05). Interferences in reading were generally found in small cortical areas, with intervening areas evoking no reading interferences. Only partial overlap between reading and naming sites was found. Reading-specific sites were preferentially found when stimulating dominant inferior parietal or posterior temporal areas. Different types of reading interferences were noted. While 'articulatory' interferences were found in pre- and postcentral gyri bilaterally, and ocular-induced movements in bilateral middle frontal gyri, paraphasias were found mainly in the dominant supramarginal and posterior superior temporal gyri. Reading arrest sites were found in many regions. Reading interference sites were also occasionally found in the non-dominant hemisphere. In bilingual patients, if common cortical areas could be found, language- and reading-specific areas were sometimes detected, lending support to the concept that bilinguals can have relatively distinct cortical representation of their language skills. Finally, in this series, the location of reading interference sites and their relative specialization showed considerable individual variability.

Adolescent↗
PubMed1994

The electroencephalogram does not predict depth of isoflurane anesthesia.

BACKGROUND: The power spectrum of the electroencephalogram (EEG) may be analyzed to provide quantitative measures of EEG activity (e.g., spectral edge, which defines the highest EEG frequency at which significant activity is found). The current study tested the hypothesis that spectral edge and similar measures distinguish different functional depths of anesthesia in humans. METHODS: Three groups were studied. Group 1 consisted of 34 surgical patients (ASA physical status 1 or 2) who received 0.6, 1.0 and 1.4 MAC isoflurane anesthesia. A subgroup (group 2) of group 1 was tested during 1.0 MAC isoflurane anesthesia at surgical incision. Group 3 consisted of 16 volunteers who listened to an audiotape while receiving 0.15, 0.3, and 0.45 MAC isoflurane or 0.3, 0.45, and 0.6 MAC nitrous oxide in oxygen. The audiotape contained information designed to test implicit and explicit memory formation. We tested the ability of six EEG parameters (spectral-edge, 95th percentile power frequency, median power, and zero crossing frequencies and total power in the alpha- [8-13 Hz] and delta- [< 4 Hz] power ranges) to predict movement after surgical incision, purposeful response to command, or memory of information presented during anesthetic administration. RESULTS: Isoflurane decreased EEG activity in group 1 in a dose-related fashion. The 55% of group 2 who made purposeful movements in response to incision did not differ in their EEG from nonresponders (e.g., spectral edge 19.8 +/- 3.1 vs. 19.3 +/- 2.6 Hz, mean +/- SD). In group 3, memory of the information presented did not correlate with values of any EEG parameter. Response to verbal command was associated with lower anesthetic concentrations and with smaller alpha- and delta-band power (298 +/- 66 vs. 401 +/- 80 watts; and 75 +/- 20 vs. 121 +/- 49 watts, mean +/- SD), but there was no difference in values for other parameters. CONCLUSIONS: We conclude that our EEG measures do not predict depth of anesthesia as defined by the response to surgical incision, the response to verbal command or the development of memory.

Adolescent↗
PubMed2006

Evaluation of a navigation system for ENT with surgical efficiency criteria.

The aim of this study is the evaluation of a navigation system (NaviBase) for ENT surgery. For this purpose, a new methodology for the evaluation of surgical and ergonomic system properties has been developed. The practicability of the evaluation instruments will be examined using the example of the overall assessment of the system in comparison with the current surgical standard and with other systems using clinical efficiency criteria. The evaluation is based on 102 ENT surgical applications; of these, 89 were functional endoscopic sinus surgeries (FESS). The evaluation of surgical and ergonomic performance factors was performed by seven ENT surgeons. To evaluate surgical system properties, the Level of Quality (LOQ) in 89 cases of the FESS was determined. It compares the existing information of the surgeon with that of the navigation system on a scale of 0 to 100 and with a mean value of 50 and places it in a relationship to the clinical impact. The intraoperative change of the planned surgical strategy (Change of Surgical Strategy) was documented. The ergonomic factors of the system with the categories of Overall Confidence (Trust), awareness of the situation (Situation Awareness), influence on the operating team, requirements for specific skills (Skill Set Requirement), and cognitive load (Workload Shift) were recorded for all surgical procedures as Level of Reliance (LOR). In the evaluation of the surgical system properties, an average evaluation of the quality of the information, as an LOQ of 63.59, resulted. Every second application of the navigation system (47.9%), on average, led to a change in the surgical strategy. An extension/enhancement of the indication of the endonasal approach through the use of the navigation system was shown in 7 of 102 (6.8%) cases. The completion of the resection in the FESS was rated by 74% of group I and 11% of group II as better in comparison with the standard approach. Total confidence shows a positive evaluation of 3.35 in the LOR. To supplement the evaluation of the navigation system, the technical parameters were included. The maximum deviation, Amax, of the displayed position of the reference value amounted to 1.93 mm. The average deviation was at 1.29 mm with an SD above all values, sd, of 0.29. The subsequent economic evaluation resulted in an effective average extra expenditure of time of 1.35 minutes per case. The overall evaluation of the system imparts application-relevant information beyond the technical details and permits comparability between different assistance systems.

Endoscopy↗
PubMed1980

Persistent left superior vena cava: Review of embryologic anatomy and considerations for cardiopulmonary bypass.

The purpose of this report is to alert the perfusionist to the anatomy of persistent left superior vena cava (PLSVC) and the intraoperative complications that this anomaly may present. The perfusionist should be able to devise a venous circuit that will accommodate three cannulae. He should also be aware that, during cardiopulmonary bypass, a copious volume of deoxygenated blood from the left heart sump, with simultaneous cerebral congestion, may signal the presence of undocumented PLSVC.

Journal Article↗
PubMed1994

The value to the anaesthetist of monitoring cerebral activity.

The administration rate of general anaesthetic drugs is at present guided by clinical experience, and indirect indicators such as haemodynamic parameters. In the presence of muscle relaxants most of the clinical signs of inadequate anaesthesia are lost and accidental awareness may occur. A number of monitoring modalities, primarily based on analysis of the electroencephalogram (EEG), have been proposed for measurement of the anaesthetic depth. Moreover intraoperative cerebral monitoring may also provide the anaesthetist with early warning of cerebral ischaemia, or information on specific neurological pathways. To facilitate this, it is essential to combine analysis of the spontaneous EEG with recording of evoked potentials, to assess both cortical and subcortical activity/events. None of the reviewed methods, however promising, can alone meet all of the requirements for intraoperative monitoring of cerebral function. We suggest that the future direction should be to integrate several modalities in a single device, to provide valuable new information, upon which to base clinical management decisions.

Anesthesiology↗
PubMedDate not supplied

The risk of fat embolism during cemented total hip replacement in the elderly patient.

The increase in intramedullary pressure in the femur is the most decisive pathogenic factor for the development of embolic phenomena during total hip replacement. The aim of this study was to assess the risk of embolism and its clinical relevance during surgery by means of transesophageal echocardiography, hemodynamic and hemogasanalytic monitoring. A total of 65 arthroplasties entered the clinical trial. Total hip arthroplasty was cemented conventionally. The right heart was monitored intraoperatively by an echocardiography probe positioned in the patient's esophagus. Hemodynamic and hemogasanalytic monitoring were performed. Severe embolism occurred in 91% of the cases during implantation of the femoral component. Emodynamic and respiratory parameters showed significant changes after major embolism. The timing suggests a nearly immediate cause-and-effect relationship. Acute hypotension was observed in 62% of the cases. Mean pulmonary shunt values increment was 30.5%. Patients with intraoperative embolism who had pre-existing associated diseases showed more severe and persistent cardiopulmonary dysfunction than healthy patients. The surgeon's proclivity to deny the clinical relevance of fat and bone marrow during during total hip arthroplasty is directly related to his awareness of and attempt to avoid embolism. Patients at risk require more intensive monitoring to obtain detailed information about hemodynamic and oxymetric parameters.

Age Factors↗
PubMed2006

A nationwide survey on the knowledge and attitudes of Malaysian optometry students on patients' visual experiences during cataract surgery.

INTRODUCTION: During cataract surgery under regional (retrobulbar, peribulbar or sub- Tenon's) or topical anaesthesia, many patients experience a variety of visual sensations in their operated eye intraoperatively. Between 3% and 16.2% of patients are frightened by their intraoperative visual experiences, which may increase the risk of intraoperative complications and affect patients' satisfaction with the surgery. This study aims to determine optometry students' beliefs and knowledge of visual sensations experienced by patients during cataract surgery under regional and topical anaesthesia. MATERIALS AND METHODS: A nationwide survey of all Malaysian optometry students using a standardised, self-administered questionnaire. RESULTS: All 129 optometry students participated in the survey, giving a 100% response rate. Overall, 26.4% and 29.5% of the students believed that patients undergoing cataract surgery under regional and topical anaesthesia, respectively, may experience no light perception, while 78.3% and 72.9%, respectively, thought that patients would experience light perception. Many respondents also believed that patients might experience a variety of other visual sensations. Of all respondents, 70.5% and 74.4% of students believed that patients undergoing cataract surgery under regional and topical anaesthesia, respectively, may be frightened by their visual experience and 93.0% and 85.3%, respectively, felt that preoperative counselling might help to alleviate this fear. CONCLUSION: Many optometry students are aware that patients might encounter a variety of visual sensations during cataract surgery under local anaesthesia. A high proportion of students believe that patients may experience fear as a result of the intraoperative visual sensations and felt that preoperative counselling would be helpful.

Adult↗
PubMed1981

New surgical approaches to pancreatic cancer.

Surgery as the best means to careful staging is stressed, in spite of many other methods of staging. Especially in those instances where resection is remotely possible it is proposed that, if possible, surgery should be done in centers specializing in this type of operation. A final opinion on the use of extended pancreatectomy awaits additional data. It is stressed that the surgeon should be fully aware of combined modality programs for treating pancreatic cancer and that new surgical techniques be considered as their proper employment demands. Finally, possible new techniques, such as intraoperative photoradiation using a laser and hematoporphyrin, intraoperative radiation therapy and heat, and the use of microwave-induced hyperthermia are discussed. The surgeon may well find that what is new in surgical treatment of cancer of the pancreas lies in a combined modality approach, primarily using intraoperative therapy.

Animals↗