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 289 records · Page 16Linked to original sources
PubMed2001

Ketamine-midazolam total intravenous anaesthesia for prolonged abdominal surgery.

BACKGROUND AND AIM: Infusion of ketamine and midazolam can maintain prolonged anaesthesia, but delayed recovery is a limitation. We aimed to develop an approximation regimen for the infusion of ketamine and midazolam to obtain steady-state anaesthesia with acceptable recovery. METHODS: Thirty-one patients undergoing radical cystectomy were studied. The initial regimen was calculated from drug pharmacokinetic variables and tailored in a pilot study (15 patients) to develop the approximation regimen dosage. Anaesthesia was induced with midazolam (150 micrograms kg-1) and ketamine (2 mg kg-1). Tracheal intubation and ventilation with oxygen enriched air (FiO2 = 0.35) were facilitated by muscle relaxants. Anaesthesia was maintained by the approximation regimen doses. Routine monitoring was used for all patients, but pulmonary artery catheters were inserted in 11 patients, to obtain haemodynamic and oxygenation variables. RESULTS: Steady-state anaesthesia was obtained with minimal deviations in the regimen in some patients followed by reasonable recovery. CONCLUSION: It is concluded that infusion of ketamine and midazolam in the approximation regimen doses can be used to maintain anaesthesia for prolonged abdominal surgery.

Abdomen↗
PubMedDate not supplied

Early clinical experience with high-frequency oscillatory ventilation for ARDS in adult burn patients.

Lung protective ventilation strategies are recommended in acute respiratory distress syndrome to avoid ventilator associated lung injury, a recently characterized complication of mechanical ventilation. High-frequency oscillatory ventilation (HFOV) is an unconventional ventilation strategy which may achieve this goal. We reviewed our experience with HFOV in six severely burned patients with acute respiratory distress syndrome. The mean age (+/- SD) of the patients was 34 +/- 13 years, and the mean TBSA burn was 52 +/- 10%, with a mean full-thickness injury of 49 +/- 12%. HFOV was initiated as "rescue therapy" in three patients with oxygenation failure (mean PaO2/FIO2 ratio of 71 +/- 8 and mean oxygenation index [OI] of 42 +/- 3) that was unresponsive to conventional ventilation (mean FIO2, 1.0 +/- 0; mean positive end expiratory pressure, 14.8 +/- 2.8 cm H2O; and mean inhaled nitric oxide, 20 +/- 0 ppm). In the other three cases, HFOV was initiated "prophylactically" as a lung protective ventilation strategy in an attempt to prevent further respiratory deterioration. All six patients showed a rapid and substantial improvement in oxygenation after initiation of HFOV, with significant improvements in the PaO2/FIO2 and OI by 12 hours (P = 0.02). In four patients HFOV was also used during anesthesia and surgery, where a total of 10 procedures involving a mean excision and closure of 15 +/- 7% TBSA burns was performed. Five of the six patients died, but none died because of oxygenation failure. In three patients death resulted from sepsis and multiple organ dysfunction syndrome; their mean PaO2/FIO2 was 107 +/- 31 and their mean OI was 30 +/- 11 immediately before death. Two patients with multiple organ dysfunction syndrome died after withdrawal of life support; their mean PaO2/FIO2 and OI were 178 +/- 31 and 18 +/- 2 respectively, at the time of this decision. Although HFOV had no impact on mortality, it played a useful role in the supportive management of burn patients with severe oxygenation failure unresponsive to conventional ventilation. Importantly, HFOV allowed surgery to proceed in patients who may have otherwise been too unstable to go to the operating room. As far as we are aware, this is the first report of the use of intraoperative HFOV in burn patients.

Adult↗
PubMed1987

Awareness under anaesthesia due to a defective gas-loaded regulator.

Awareness under anaesthesia occurred in two patients due to a defect in an anaesthesic machine, which caused an inadequate supply of nitrous oxide. A defective fail-safe gas-loaded regulator was found to have caused communication between the pipelines for oxygen and nitrous oxide. This resulted in oxygen flow through the nitrous oxide flowmeter. A simple test to detect this type of defect is suggested.

Anesthesia, Inhalation↗
PubMed2005

Different conditions that could result in the bispectral index indicating an incorrect hypnotic state.

Since its introduction in 1996, the Bispectral Index (BIS) has gained increasing popularity in daily anesthesia practice. However, numerous reports have been appearing in the literature of paradoxical BIS changes and inaccurate readings. The purpose of this review is to assess the utility of BIS monitoring through examining the various published reports of all BIS values not coinciding with a clinically judged sedative-hypnotic state, whether arising from an underlying pathophysiology of electroencephalographic (EEG) cerebral function or because of shortcomings in the performance and design of the BIS monitor. High electromyographic activity and electric device interference could create subtle artifact signal pollution without their necessarily being displayed as artifacts. This would be misinterpreted by the BIS algorithm as EEG activity and assigned a spuriously increased BIS value. Numerous clinical conditions that have a direct effect on EEG cerebral function could also directly influence the BIS value.

Anesthesia↗
PubMed1987

Incidents of auditory perception during anaesthesia with traumatic sequelae.

The literature on auditory perception during anaesthesia, while by no means scarce, presents contradictory experimental findings; its reported prevalence ranges from nil to 80%. Due to their anecdotal nature and lack of control, case histories are difficult to evaluate statistically. Nevertheless, they provide a broader base for the understanding of the phenomenon and its implications. Two case histories are presented, both with traumatic sequelae. In the first case, the anaesthetist confirmed his off-the-cuff utterance that was perceived by the patient and retained in the anaesthetized patient's memory and acted upon by the patient postoperatively. A possible explanation of auditory perception and its behavioural characteristics are outlined. A suggestion is offered for the potential beneficial application of auditory perception during anaesthesia.

Adult↗
PubMed2001

[Efficiency of bispectral index in anesthetic management of a patient with hypothyroidism].

A 72-year-old, female patient with severe hypothyroidism underwent tracheostomy using deltopectral flap. During the anesthetic management, we assessed the hypnotic level using the bispectral index and regulated the dose of general anesthetics to maintain the bispectral index at about 50. The general anesthetics caused a marked cardiovascular depression, but the condition was treatable with the intravenous administration of dopamine. Using these methods, we could anesthetize this patient safely without a prolonged awakening time from general anesthesia. Although the anesthetic requirement for patients with hypothyroidism is generally thought to be decreased, there is no practical index by which we can estimate the optimal dose of anesthetic agents for these patients. This case report shows that the assessment of the hypnotic level by the bispectral index can be utilized as an efficient index to determine the optimal dose of general anesthetics for patients with hypothyroidism.

Aged↗
PubMed1985

Anesthesia, amnesia, and the memory/awareness distinction.

Several studies have shown that surgical patients cannot consciously recall or recognize events to which they had been exposed during general anesthesia. Might evidence of memory for intraoperative events be revealed through the performance of a postoperative test that does not require remembering to be deliberate or intentional? Results of the present study, involving the recognition and spelling of semantically biased homophones, suggest a negative answer to this question and imply that intraoperative events cannot be remembered postoperatively, either with or without awareness.

Adult↗
PubMed1999

The complications of blepharoplasty: their identification and management.

BACKGROUND: Because of the increasing number of blepharoplasties being done by cosmetic dermatologists, it is necessary to have an increased awareness of sequella and complications. OBJECTIVE: To review the frequent complications following blepharoplasty and to develop methods for their prevention and treatment. METHOD: A thorough history and physical combined with accurate intraoperative markings and postoperative instructions can make the procedure more predictable. CONCLUSION: Armed with an awareness of possible blepharoplasty complications, an adequate history and physical can point to areas of concern. If these guidelines are observed, a blepharoplasty can be completed that keeps both the physician and patient satisfied.

Blepharoplasty↗
PubMed1997

Incidence of awareness in total i.v. anaesthesia based on propofol, alfentanil and neuromuscular blockade.

BACKGROUND: There is no reliable technique for monitoring drug concentrations in total i.v. anaesthesia (TIVA) with muscle relaxation. An increased risk of awareness with TIVA has been stated as a possible drawback. The present study was conducted in order to assess the incidence of conscious awareness in TIVA based on propofol, alfentanil and neuromuscular blockade. METHODS: One thousand patients anaesthetized with TIVA based on propofol, alfentanil, and neuromuscular blockade were subjected postoperatively to a structured interview for conscious awareness on two separate occasions: on discharge from the post-anaesthesia care unit, and the day after anaesthesia. Five hundred of these patients were also interviewed a third time, approximately 1 week later. RESULTS: Two cases of awareness were detected (0.2%). One of these was identified immediately after extubation. The second patient had no memory of intraoperative events or dreams at the first interview, recalled a bad dream on the day after, and had explicit recall of intraoperative events at the interview 8 days later. In both cases, haemodynamic signs of inadequate anaesthesia were present. The incidence of conscious awareness in this study is similar to the lowest previously reported incidence of awareness following general anaesthesia in patients who had been paralyzed and thereafter subjected to a structured postanesthesia interview. CONCLUSIONS: If the true incidence of conscious awareness is to be determined, interviews must be extended beyond the first postoperative day. Our study indicates that if appropriate dosing of propofol and alfentanil are adhered to, and proper action is taken in case of haemodynamic alterations suggestive of inadequate anaesthesia, the incidence of conscious awareness in non-cardiac TIVA with neuromuscular blockade is low.

Adolescent↗
PubMed1998

Risk of patients with severe aortic stenosis undergoing noncardiac surgery.

Aortic stenosis (AS) is a major risk factor for perioperative cardiac events in patients undergoing noncardiac surgery. We previously showed that selected patients with AS who were not candidates for, or refused, aortic valve replacement could undergo noncardiac surgery with acceptable risk. We extended our previous experience over a subsequent 5-year period by retrospectively analyzing the perioperative course of all patients with severe AS (aortic valve area index < 0.5 cm2/m2 or mean gradient > 50 mm Hg), determined with Doppler echocardiography or cardiac catheterization, who underwent noncardiac surgery. Nineteen patients underwent 28 surgical procedures: 22 elective and 6 emergency. The types of these procedures were 12 orthopedic, 6 intraabdominal, 4 vascular, 4 urologic, 1 otolaryngologic, and 1 thoracic. Mean age was 75 +/- 8 years. Of the 19 patients, 16 (84%) had > or = 1 symptom: dyspnea, angina, syncope, or presyncope. Mean left ventricular ejection fraction was 61 +/- 11%. The type of anesthesia was general in 26 procedures and continuous spinal in 2. Intraarterial monitoring of blood pressure was used in 20 of the 28 surgical procedures. Intraoperative hypotensive events were treated promptly, primarily with phenylephrine. In all cases the anesthesia team was aware of the severity of the AS and integrated this into the anesthetic plan. Two patients (elective operation in 1 and emergency in 1) had complicated postoperative courses and died. There were no other intraoperative or postoperative events in any of the other patients. Although aortic valve replacement remains the primary treatment for patients with severe AS, selected patients with severe AS, who are otherwise not candidates for aortic valve replacement, can undergo noncardiac surgery with acceptable risk when appropriate intraoperative and postoperative management is used.

Aged↗
PubMed2003

Hypertensive crisis inducing rhabdomyolysis during laparoscopic resection of a large pheochromocytoma: a case report.

Intense vasospasm during hypertensive crisis as a cause for rhabdomyolysis has been described in ambulatory patients with pheochromocytoma. We report this phenomenon as an intraoperative complication in a patient during laparoscopic pheochromocytoma resection and discuss patient and procedure related risk factors. Unexplained intraoperative hyperkalemia following a severe hypertensive episode during surgery may be a first sign of rhabdomyolysis. Anesthesiologists should be aware of such a possibility. Intra- and postoperative serial electrolyte determinations and if suspected, timely screening for myoglobiuria, may aid in early detection and treatment of intraoperative rhabdomyolysis during pheochromocytoma resections.

Adrenal Gland Neoplasms↗