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 325 records · Page 18Linked to original sources
PubMed1990

Effects of incremental ketamine hydrochloride doses on motor evoked potentials (MEPs) following transcranial magnetic stimulation: a primate study.

the cumulative dose effect of ketamine hydrochloride (KH) on transcranial magnetic-induced motor evoked potentials (MEPs) was examined in monkeys. Electromyographic (EMG) responses were recorded from the contralateral abductor pollicis brevis (APB) and abductor hallucis (AH) muscles. MEP brain stimulation threshold, latency, and amplitude values were studied. After obtaining baseline recordings, increments of KH (5 mg/kg every 15-20 min) were given i.v. (50 mg/kg total dose). MEPs were repeatedly recorded following KH injections. No loss of potentials was encountered in any animal. However, KH induced significant MEP latency delay in doses >/=35-40 mg/kg and amplitude depression in doses >/=15-20 mg/kg (p < 0.01). Under various KH doses, the amplitude depression ranged from 13.6 to 45.5% for APB and 57.3 to 82% for AH compared to the control values. The MEP latency prolongation ranged from 3.5 to 18% for APB and 4.2 to 13.1% for AH. The stimulation threshold rise ranged from 6.7 to 14.7% for APB and 7 to 17.9% for AH. Statistical correlation was closest between cumulative KH doses and MEP latency prolongation. We conclude that, in the primate model, reliable MEP recording is feasible under deep KH anesthesia. However, awareness of drug-induced response alterations is essential during interpretation of intraoperative MEP changes. Further investigation is warranted regarding the specific dose effect in humans and safety of magnetic stimulation.

Journal Article↗
PubMed1980

Intra-operative awakening during scoliosis surgery.

A method of intra-operative awakening which allows assessment of spinal cord function during Harrington rod spinal fusion for scoliosis is described. The anaesthetic technique is based on a standard muscle relaxant, N2O anaesthetic sequence supplemented with intravenous morphine 0.1 mg/kg at the commencement of surgery and 0.2 mg/kg intramuscular premedication. This relatively large total dose of morphine may reduce intra-operative awareness, and may also provide substantial pain relief during the initial 24 h postoperative period. It has been used successfully in 20 patients aged between 6 and 16 yr. Five patients remembered being woken, but did not regard it as unpleasant. In one patient, this technique allowed intra-operative detection and correction of impaired motor function of the legs.

Adolescent↗
PubMed1991

Awareness during caesarean section.

Between 1982 and 1989 over 3000 patients were questioned about recall and dreaming after general anaesthesia for Caesarean section. Some 28 (0.9%) patients were able to recall something of their operation and 189 (6.1%) reported dreams. There was uniform adherence to a rigid anaesthetic protocol up to and including 1985, but a much publicized incident reported from the courtroom stimulated a relaxation of this regimen. Consequently the incidence of awareness decreased from 1.3% to 0.4%, and the incidence of dreaming was also reduced. Recollections of surgery were confined to manipulations, noises and voices. None of our patients complained of pain at the time of interview, although one since has. The inadequacies of the initial protocol and an approach to informed consent are discussed.

Adult↗
PubMed2004

Auditory evoked potentials.

Auditory evoked potentials (AEPs) are an electrical manifestation of the brain response to an auditory stimulus. Mid-latency auditory evoked potentials (MLAEPs) and the coherent frequency of the AEP are the most promising for monitoring depth of anaesthesia. MLAEPs show graded changes with increasing anaesthetic concentration over the clinical concentration range. The latencies of Pa and Nb lengthen and their amplitudes reduce. These changes in features of waveform are similar with both inhaled and intravenous anaesthetics. Changes in latency of Pa and Nb waves are highly correlated to a transition from awake to loss of consciousness. MLAEPs recording may also provide information about cerebral processing of the auditory input, probably because it reflects activity in the temporal lobe/primary cortex, sites involved in sounds elaboration and in a complex mechanism of implicit (non declarative) memory processing. The coherent frequency has found to be disrupted by the anaesthetics as well as to be implicated in attentional mechanism. These results support the concept that the AEPs reflects the balance between the arousal effects of surgical stimulation and the depressant effects of anaesthetics. However, AEPs aren't a perfect measure of anaesthesia depth. They can't predict patients movements during surgery and the signal may be affected by muscle artefacts, diathermy and other electrical operating theatre interferences. In conclusion, once reliability of the AEPs recording became proved and the signal acquisition improved it is likely to became a routine feature of clinical anaesthetic practice.

Anesthesia↗
PubMed1989

[Deep cystic colitis located in a previous surgical anastomosis].

Deep cystic colitis is a rare disease of which about one hundred cases have been reported in the medical literature. Two forms are known, segmental and localized, the latter being the most frequent. We offer a case of a patient who developed a picture of deep localized cystic colitis on a previous surgical anastomosis, a very infrequent association. The value of intraoperative biopsy in these cases is discussed. It is necessary to be aware of this entity and its clinicopathologic correlations to differentiate it, especially from the therapeutic and prognostic points of view, from well differentiated colorectal carcinoma and colloid (mucoid extracellular) carcinoma.

Aged↗
PubMed1994

Double burst stimulation with submaximal current.

The present study evaluated responses to double burst stimulation (DBS) at supramaximal and submaximal currents in 30 adult patients. Usually, DBS is applied with supramaximal stimulation, but this may be quite uncomfortable for the awake patient. Therefore, the authors investigated whether it is possible to obtain an accurate assessment of significant residual neuromuscular blockade if the stimulus current is reduced to 30 mA. In all patients, neuromuscular response to DBS three three (DBS3.3), DBS three two (DBS3.2) and train-of-four (TOF) stimulation at supramaximal and/or submaximal currents was recorded using a mechanomyograph, and the ratios of the fourth to the first twitch (T4/T1) induced by TOF stimulation at supramaximal current, and the height of the second response to the first (D2/D1) induced by DBS at 30 mA and supramaximal current were calculated. The relations between control T4/T1 ratios determined by supramaximal TOF stimulation and D2/D1 ratios determined by supramaximal DBS3.3 and submaximal DBS3.3 were Y = 0.99X + 0.08 and Y = 1.01X + 0.04, respectively, and there was no statistical difference between the two regression lines. The same relation between T4/T1 ratios and D2/D1 ratios by DBS3.2 were Y = 0.69X + 0.05 and Y = 0.72X + 0.02, respectively, and there was no significant difference. It is concluded that evaluation of the response to DBS at 30 mA has the same reliability as evaluation with supramaximal current.

Adult↗
PubMed1996

Laparoscopic surgical management of ovarian cysts assisted by simultaneous transvaginal ultrasonography.

OBJECTIVE: To assess the use of transvaginal ultrasound guidance during operative laparoscopy. STUDY DESIGN: Five of 98 consecutive cases of operative laparoscopy for benign-appearing ovarian cysts were complicated by extensive intrapelvic adhesions and a distorted anatomy. Following prolonged dissection, simultaneous transvaginal ultrasonography was used in these cases. RESULTS: In all cases we were able to ultrasonographically image and locate the ovarian cyst during the laparoscopic procedure. In four cases this was a significant aid in expediting the procedure and avoiding damage to adjacent pelvic structures. In one case, identification of the ovarian cyst facilitated the decision to resort to laparotomy. CONCLUSION: In selected cases, laparoscopic surgeons should be aware of the feasibility and possible benefits of the use of simultaneous intraoperative transvaginal ultrasonography.

Adnexal Diseases↗
PubMed1998

[Dosage of anesthetics--a tricky question].

The optimal dosage of anaesthetic agents may be difficult. Not only does the intensity of surgical stimuli vary during a surgical procedure, but drug sensitivity varies between subjects exposed to comparable stimuli. Moreover, clinically monitored body reactions do not always reflect the balance between central nervous system effects of the surgical stimuli and of the anaesthetic agent. Therefore, the specialist in anaesthesiology requires access to additional methods of monitoring to enable dosage to be optimised for each patient, minute by minute, thus improving the chances of maintaining an appropriate depth of anaesthesia. Two electro-encephalographic techniques are presented in the article, and aspects of under- and over-dosage of anaesthetic agents are discussed.

Anesthetics, General↗
PubMed2005

Assessing team performance in the operating room: development and use of a "black-box" recorder and other tools for the intraoperative environment.

BACKGROUND: The objective of this research was to develop a digital system to archive the complete operative environment along with the assessment tools for analysis of this data, allowing prospective studies of operative performance, intraoperative errors, team performance, and communication. Ability to study this environment will yield new insights, allowing design of systems to avoid preventable errors that contribute to perioperative complications. STUDY DESIGN: A multitrack, synchronized, digital audio-visual recording system (RATE tool) was developed to monitor intraoperative performance, including software to synchronize data and allow assignment of independent observational scores. Cases were scored for technical performance, participants' situational awareness (knowledge of critical information), and their comfort and satisfaction with the conduct of the procedure. RESULTS: Laparoscopic cholecystectomy (n = 10) was studied. Technical performance of the RATE tool was excellent. The RATE tool allowed real time, multitrack data collection of all aspects of the operative environment, while permitting digital recording of the objective assessment data in a time synchronized and annotated fashion during the procedure. The mean technical performance score was 73% +/- 28% of maximum (perfect) performance. Situational awareness varied widely among team members, with the attending surgeon typically the only team member having comprehensive knowledge of critical case information. CONCLUSIONS: The RATE tool allows prospective analysis of performance measures such as technical judgments, team performance, and communication patterns, offers the opportunity to conduct prospective intraoperative studies of human performance, and allows for postoperative discussion, review, and teaching. This study also suggests that gaps in situational awareness might be an underappreciated source of operative adverse events. Future uses of this system will aid teaching, failure or adverse event analysis, and intervention research.

Cholecystectomy, Laparoscopic↗
PubMed2003

Prepancreatic postduodenal portal vein: report of a case.

We report an unusual case of a prepancreatic postduodenal portal vein (PPPV), incidentally discovered during total gastrectomy. If it had not been noticed, this portal vein might have been ligated and divided with disastrous consequences. This anomaly was not diagnosed preoperatively, but it could have been. Although embryological anomalies of the portal venous system, such as PPPV and preduodenal portal vein, are rarely encountered in abdominal surgery, surgeons must be aware of their possibility and be able to recognize them to avoid major intraoperative injury.

Congenital Abnormalities↗
PubMed2001

Cataract surgery by phacoemulsification in adults with retinopathy of prematurity.

PURPOSE: To report the preoperative, operative, and postoperative factors associated with phacoemulsification cataract surgery in adults with retinopathy of prematurity. METHODS: Records of patients with retinopathy of prematurity who underwent phacoemulsification at The Wilmer Institute between January 1990 and January 2000 were retrospectively searched. Seventeen adults (9 women, 8 men) with retinopathy of prematurity were identified who had undergone phacoemulsification for visually significant cataract or phacomorphic glaucoma and who had at least 6 months of postoperative follow-up. RESULTS: Cataract extraction by phacoemulsification was performed on 20 eyes. Follow-up ranged from 6 to 103 months (mean, 32 months). A posterior chamber intraocular lens was placed in 18 eyes; two eyes were left aphakic for refractive reasons. Zonular weakness was noted in two eyes in which the intraocular lens was suture fixated to the sclera. Concomitant trabeculectomy was performed in one eye. Visual acuity improved in 18 of 20 eyes and remained unchanged in two eyes. Postoperatively, visual acuity was worse than 5/200 in two eyes, 5/200 to worse than 20/100 in five eyes, 20/100 to 20/50 in five eyes, and 20/40 or better in eight eyes. One eye developed a rhegmatogenous retinal detachment 1 month after cataract surgery; the retina was successfully reattached. CONCLUSIONS: Although cataract extraction in eyes with regressed retinopathy of prematurity may present challenges, such as high myopia, monocularity, glaucoma, and previous ocular surgery, phacoemulsification in this series proved to be relatively safe as well as visually rehabilitating. The surgeon should be aware of the special considerations in this population, alert to potential zonular weakness intraoperatively, and careful of increased postoperative risks, including retinal detachment.

Adolescent↗
PubMed1991

Cataract surgery in anticoagulated patients.

A prospective study was performed on 31 patients having planned extracapsular cataract extraction with posterior chamber intraocular lens implantation. The patients were considered to be anticoagulated because of the medications they were taking. The patients were instructed to continue their usual medications throughout the perioperative period including the day of surgery. All patients had routine narcoleptic sedation and retrobulbar anesthesia. The surgical technique was altered to use an inferior corneal traction suture and a single planed clear corneal incision. No intraoperative or postoperative anterior chamber bleeding was seen. The observed complications were increased awareness of corneal sutures, increased endothelial cell loss, delayed visual rehabilitation from with-the-rule astigmatism, and transient corneal edema. All patients achieved 20/40 or better visual acuity without corneal edema by three months post-surgery.

Aged↗
PubMed2005

Posterolateral rotatory instability of the elbow following radial head resection.

BACKGROUND: Resection is a common procedure for the treatment of comminuted fractures of the radial head. While radial head resection is associated with a high success rate when performed for appropriate indications, a number of well-defined biomechanical complications have been reported following this procedure, including proximal migration of the radius, the development of valgus deformity, and recurrent elbow instability in the acute setting. However, posterolateral rotatory instability has not previously been recognized as a complication of radial head resection. While the absence of the radial head makes the diagnosis difficult, we have identified a series of patients with posterolateral rotatory instability following radial head resection. We believe that this instability is secondary to unrecognized lateral ulnar collateral ligament deficiency. METHODS: Between November 1995 and September 2000, forty-two patients were evaluated because of elbow or forearm complaints following radial head resection. Seven patients (17%) were diagnosed with posterolateral rotatory instability on the basis of characteristic clinical and radiographic findings. RESULTS: The study group included five men and two women with a mean age of forty-two years. All seven patients had had radial head excision for the treatment of a comminuted radial head fracture at a mean of forty-four months (range, four months to sixteen years) prior to referral. All seven patients had lateral elbow pain, a sense of instability and/or weakness, and a positive lateral pivot-shift test. Posterolateral rotatory instability secondary to lateral ulnar collateral ligament insufficiency was confirmed intraoperatively in the four patients who were managed surgically. CONCLUSIONS: Clinicians should be aware that posterolateral rotatory instability may be a cause of unexplained elbow pain and instability following radial head resection. This diagnosis has implications for the prevention and treatment of this condition.

Adult↗