Biomedical subjects

A J Asbury

Publications and source records attributed to A J Asbury.

At least 19 recordsLinked to original sources

PubMed2003

Pre-operative screening: criteria for referring to anaesthetists.

Nurses assess patients pre-operatively using screening questionnaires and locally-developed protocols. Our objectives were to determine which questions might identify patients who should be seen by an anaesthetist before the day of surgery. A review of the literature and a preliminary questionnaire to establish questions to be tested was followed by a modified, two-round Delphi questionnaire to determine the level of agreement by anaesthetists. There was agreement for referring patients who gave a positive response to questions that query: restricted exercise tolerance; previous anaesthetic problems; family history of anaesthetic problem; pathology affecting neck movement; angina; arrhythmia; heart failure; asthma; epilepsy; insulin-dependent diabetes mellitus; liver disease and unspecified kidney disease. There was equivocal agreement on questions that report a myocardial infarction over one year ago, cerebrovascular accident, non insulin-dependent diabetes mellitus and thyroid disease. Nurses should use these criteria during pre-operative assessment to decide the timing of evaluation by an anaesthetist.

Anesthesiology↗

PubMed2001

Pre-existing cognitive impairment as a factor influencing outcome after cardiac surgery.

Conventional methodology to investigate cognitive impairment after coronary artery bypass graft (CABG) surgery leaves unclear the potential for pre-existing cognitive deficits to influence outcome. Individuals with pre-existing deficits may be more vulnerable to the effects of CABG, hence biasing the results of a typical prospective trial if account is not taken of their state. The present study examined the effect of pre-existing cognitive impairment upon cognitive outcome in 81 patients undergoing CABG. Patients performed the Stroop Neuropsychological Screening Test and other psychometric assessments prior to and at 6 days and 6 months after CABG. Those with pre-existing cognitive deficits were significantly more likely to display impairment at 6-day and 6-month follow-ups than were those without pre-existing deficits. Greater age and lower pre-morbid intelligence were also significant predictors of post-CABG deficit, confirming earlier findings. The results imply both that pre-existing cognitive impairments may render patients more vulnerable to post-operative deficits and that, in the absence of such pre-existing impairments, CABG surgery does not inevitably lead to later deficits. The study also replicated previous findings showing a similar influence of pre-existing depression upon emotional state after CABG. Overall, the results confirm the importance both of a patient's pre-existing cognitive and emotional states, and the methodology to assess them, in influencing outcome after cardiac surgery and the conclusions to be drawn as to the supposed adverse effects of the procedure.

Adult↗

PubMed1999

Theatre monitor alarm settings: a pilot survey in Scotland and Belgium.

The use of alarms on operating theatre equipment was explored in a questionnaire to anaesthetists in Belgium and Scotland. They were presented with a scenario of a fit male having an anaesthetic for an abdominal operation. The overall response rate was 72%, giving 100 records for analysis. The responses from Scottish and Belgian anaesthetists were similar except for views on setting an upper limit for systolic arterial pressure; Scottish anaesthetists seemed relatively unwilling to set an upper systolic arterial pressure limit. Beyond this, the respondents considered alarms to be a method of detecting problems before they occur and they readjust alarms for each patient. They would set systolic arterial pressure alarms 30 mmHg above and below the patients normal pressure, the heart rate alarms 30 bpm above and 20 bpm below the actual rate, and the peripheral oxygen saturation lower alarm limit to 90%.

Abdomen↗

PubMed1998

How would patients prefer to spend the waiting time before their operations?

Many surgical patients are anxious while waiting to go to the operating theatre in spite of the best preparation with drugs, information and reassurance. It is possible that patients could be more comfortable if allowed a choice of activities before operations. The objective of this study was to find out how pre-operative patients might prefer to occupy their time. We distributed 200 questionnaires to elective surgery patients and 184 (92%) were available for analysis. Of the respondents, 54.1% wanted to be slightly sleepy, 72.0% preferred not to be fast asleep and 57.2% preferred not to be wide awake. Reading (56.8%), listening to music (57.1%) and chatting with other patients (39.9%) were preferred activities. It might be appropriate to ask patients how sedated they would wish to be before their surgery and perhaps have alternatives to sedation available.

Adult↗

PubMed1998

The effect of music on anaesthetists' psychomotor performance.

Music is frequently played in operating theatres, but may prove distracting to anaesthetists. We undertook a laboratory-based study of the effects of music on the psychomotor performance of 12 anaesthetic trainees. Using part of the computer-based PsychE psychomotor evaluation programme, we were unable to demonstrate any effect of self-chosen music, silence, white noise or classical music on their performance in these tests.

Adult↗

PubMed1998

A system for psychomotor evaluation; design, implementation and practice effects in volunteers.

This paper describes the design, implementation and assessment of PsychE, psychomotor evaluation system. Six standard tests are included: numeric vigilance, a dual task, probed memory recall, simple reaction time, choice reaction time and semantic long-term memory. The test presentations are described in detail. Practice effects were assessed in 10 healthy volunteers and were only evident in the performance measures for the simple reaction time test. For the remaining five tests, stable performance was reached within a single test session. The volunteers were healthy and most were regular users of computers. Therefore, the lack of practice effects cannot be assumed for the general population. A control group is essential for all studies using these tests. The system is implemented on an IBM-compatible personal computer and includes a database shell for the convenient collection, storage and analysis of performance data.

Adolescent↗

PubMed1998

Pressure changes over the anterior neck during tracheal and oesophageal intubation.

Pressure changes were measured on the skin over the cricoid and thyroid cartilages during intubation of the oesophagus or trachea in 21 consenting patients. A 100-ml bag of saline was firmly fixed to the anterior neck and the pressure changes in the bag recorded. Typical and distinctively different pressure patterns for tracheal and oesophageal intubation were recorded. Oesophageal intubation was accompanied by a statistically significantly higher and longer pressure rise and, most characteristically, by an obvious and sustained rise in baseline pressure. This method is, however, neither practical nor recommended for clinical use in detecting accidental oesophageal intubation. Capnography should always be used during tracheal intubation as an ongoing capnographic waveform provides the only guarantee of correct tracheal placement.

Adult↗

PubMed1997

Feedback control in anaesthesia.

This review considers the some of the methods of automatic control which are usable in medicine. The features of each type of control system are explained and the advantages and disadvantages summarised. The author has attempted to maintain a balance between what is possible with the excellence of modern engineering, and what is feasible in the clinical area, and practical when working with patients. The problem of lack of knowledge of an individual patient is emphasised, as is the potential of fuzzy logic methods in the future.

Anesthesiology↗

PubMed1997

Detection of accidental oesophageal intubation. Role of the anaesthetic assistant.

Three situations in which an anaesthetic assistant might be able to detect accidental oesophageal intubation during or immediately after intubation were assessed. These were: firstly, whilst applying cricoid pressure, secondly, whilst applying gentle palpation over the trachea just above the suprasternal notch and, thirdly, after intubation by means of a 'roll test'. During cricoid pressure, tracheal intubation was correctly diagnosed in all of 10 cases. However, deliberate oesophageal intubation was only detected in six out of 10 cases. During suprasternal palpation, three cases out of 10 oesophageal and three cases out of 10 tracheal intubation were misdiagnosed. In the 'roll test', two out of 10 tracheal and five out of 10 oesophageal intubations were misdiagnosed. In conclusion, no method could be relied on entirely and may indeed give false reassurance. Nonetheless, any doubt expressed about the tracheal tube position by the assistant should be taken seriously and a careful check made.

Adolescent↗

PubMed1997

Music in theatre: not so harmonious. A survey of attitudes to music played in the operating theatre.

Music played to staff in the operating theatre is thought to improve surgeons' concentration but its effects on other theatre staff are unknown. We surveyed 200 anaesthetists to determine the prevalence of music playing in the operating theatre and anaesthetists' attitudes to it. The response rate was 72% and of these 72% (104) worked in a theatre where music was played regularly. Around 26% of the sample felt that music reduced their vigilance and impaired their communication with other staff while 11.5% felt that music might distract their attention from alarms. Fifty-one per cent felt that music was distracting when a problem was encountered during the anaesthetic.

Adult↗

PubMed1996

Pupil changes during cardiopulmonary bypass.

Pupil diameter is used during anaesthesia to assess depth of anaesthesia and indicate cerebral hypoxia. This is especially so during cardiac bypass when other autonomic signs cannot be monitored. We have used a pupillometer to determine the effect of cardiopulmonary bypass on the pupil. We have also investigated if any effect was caused by washout of opioid from the central nervous system by allocating patients to one of two groups: in one the bypass pump was preloaded with fentanyl, in the other with 0.9% saline. Cardiopulmonary bypass caused pupil dilatation of between 17% and 53%, which was unaffected by preloading the bypass pump with fentanyl. This effect lasted for the duration of the study, which ended 30 min after the start of cardiopulmonary bypass. Sympathetic nervous system reflexes and hypothermia may account for this observation, but further research is necessary to exclude other contributory factors.

Aged↗

PubMed1996

Cognitive failures after general anaesthesia for day-case surgery.

Patients are normally thought to have recovered from general anaesthesia within a few hours after day-case surgery. Previous recovery studies using objective psychometric tests showed a return to baseline values within this period. Nevertheless, patients are advised about what activities they should not undertake in the subsequent 24 h because it is feared that the residual anaesthetic effects may impair their ability. These studies did not follow patients out of hospital and their relevance to the real world is not known. Using the cognitive failures questionnaire, a standard measure of performance of everyday tasks, 54 patients were asked to report their own performance after general anaesthesia for the 3 days after discharge from hospital: 30 local anaesthetic patients were studied for comparison. The general anaesthesia group reported a highly significant greater incidence of cognitive failures after anaesthesia compared with the local anaesthesia group. This suggests that the residual effects of anaesthesia persist beyond 24 h.

Activities of Daily Living↗

PubMed1996

Comparison of the effect of two dose schedules of oral omeprazole with oral ranitidine on gastric aspirate pH and volume in patients undergoing elective surgery.

We have compared gastric aspirate pH and volume at induction of anaesthesia in 222 patients who had received either omeprazole or ranitidine before elective operations. Omeprazole was given orally either as 40 mg on the evening before and 40 mg on the morning of surgery or as 80 mg on the morning of surgery. Ranitidine 150 mg was given orally on the evening before surgery and 2 h before anaesthesia. Treatment success was defined as aspirate pH > or = 2.5 and volume < 25 ml at induction of anaesthesia. Treatment was successful in 84% (95% confidence interval (CI) 73-91%) of patients in the omeprazole 40 + 40 mg group, 84% (95% CI 73-91%) in the ranitidine group and 73% (95% CI 61-83%) in the omeprazole 80 mg group. There were no statistically significant differences between the groups. Twelve patients in the omeprazole 80 mg group had gastric pH < 2.5 and four had volume > 25 ml. Only three patients had a gastric pH < 2.5 in the omeprazole 40 + 40 mg group and none had volume > 25 ml, which compared well with the ranitidine group. Omeprazole, given as 40 mg in the evening and 40 mg on the morning of operation, has a potential role for use in patients at risk for aspiration during general anaesthesia.

Adolescent↗

PubMed1996

Comparison of patient-controlled sedation with either methohexitone or propofol.

We studied 42 patients undergoing oral surgery under local anaesthesia with i.v. sedation, allocated randomly to receive either methohexitone (group M) or propofol (group P) for patient-controlled sedation (PCS). Group M patients self-administered 2.5-mg (0.5 ml) bolus doses of methohexitone and group P, 5-mg (0.5 ml) doses of propofol, without a lockout. The 0.5-ml bolus dose was delivered over 7.2 s for both drugs. The procedure was completed satisfactorily in all patients. Patients in both groups achieved their desired levels of sedation. No patient lost verbal contact. Group M patients had higher heart rates during the procedure. The lowest SpO2 values recorded were 92% and 95% for group P and group M, respectively. Immediately after operation patients in group M reported that they felt more sleepy than those in group P (P < 0.01) but there were no differences at subsequent times. The results of the psychomotor tests were comparable for the two groups after operation, except for the "posting box task" at 15 min after operation when the mean decrement (compared with preoperative performance) was -3% for group P and -13% for group M (P < 0.05). More patients in group P complained of pain in their hand. We conclude that methohexitone is a suitable alternative drug to propofol for PCS.

Adult↗

PubMed1996

The Glasgow Pain Questionnaire: a new generic measure of pain; development and testing.

BACKGROUND: The study set out to develop and test a measure of perceived pain suitable for use in community studies and in the evaluation of clinical care. METHOD: The work had three parts; (1) generation and selection of items, (2) weighting of the items and (3) testing for reliability and validity. Potential items were obtained from 230 informal interviews conducted in a variety of settings. These were reviewed to produce a draft questionnaire, and this was used in a pilot study of 60 volunteers to determine the final item selection. Item weights were calculated using ratings of severity as judged by subjects in the pilot study and the validity testing. Weights are used so that questions referring to more severe pains have higher scores than those about milder pains. Reliability and validity testing was carried out using three groups: 100 rheumatoid arthritis outpatients; 37 attenders at an occupational health clinic and 178 chronic pain clinic patients. Scores from the three different patient groups were compared, scores were compared with a visual analogue measure of pain, and scores from the same individuals from two consecutive months were compared. RESULTS DEVELOPMENT: The main product was the new measure itself, the Glasgow Pain Questionnaire (GPQ). This has a total of 24 items in five categories; pain frequency, intensity, emotional reaction, ability to cope and restrictions of daily activity. TESTING: Validity; scores were significantly different in the three groups. The GPQ scores were significantly related to the visual analogue measure of pain. Reliability; scores of the same respondents on two consecutive months were significantly associated and had a modal value of zero. CONCLUSIONS: The project has produced a new measure of self-rated pain suitable for use in large-scale population surveys. This instrument assesses not only pain intensity but affective dimensions of pain. It is considered that the validity and reliability testing carried out to date show the measure as acceptable for use in future studies.

Adolescent↗

PubMed1996

A novel device for patient-controlled sedation: laboratory and clinical evaluation of the Baxter Intermate LV250 infusor and patient-control module.

The Baxter Intermate LV250 infusor is a large capacity, high flow mechanical infusor, designed to deliver viscous solutions and suspensions. The objective of the laboratory study was to evaluate the LV250 infusor when used with either 0.9% sodium chloride solution or an emulsion, propofol 1%. Following this, the LV250 infusor with the patient-control module was assessed in the clinical setting as to its suitability for use in patient-controlled sedation with a propofol and lignocaine mixture. Between reservoir volumes of 250 and 55 ml, the LV250 infusor was found to infuse a propofol 1% and lignocaine mixture at a lower flow compared with the sodium chloride solution, 170 ml.h-1 and 260 ml.h-1 respectively. The lower flow with the propofol mixture may be a result of its higher viscosity. All patients using the LV250 infusor for patient-controlled sedation found it easy to use and stated that they were able to achieve their desired level of sedation. All patients maintained arterial oxygen saturations above 95%. The LV250 infusor performed reliably and with little inter-device variation, and with the patient-control module could be used as an alternative to electronic devices for providing patient-controlled sedation. Compared with electronic infusors, its advantages include compactness and simplicity of design.

Anesthetics, Intravenous↗

PubMed1996

Attitudes to pain and pain relief in adult surgical patients.

Pain relief after surgery is frequently inadequate. In the last few years much research has been devoted to improving the situation. Unfortunately, very little work has been undertaken to explore the patients' contribution to pain management. The beliefs and attitudes held by patients when they enter the hospital environment may be responsible in some instances for their not achieving optimal pain relief from the available techniques. We have studied some of these attitudes with a survey of 180 adult patients admitted for elective surgery. We found that most patients still expect pain following surgery. However, they are not afraid to ask for analgesics when in pain and do not attribute pain to their own wrong doing. There are, however, some patients who appear to have 'deviant' pain beliefs that could hinder their appropriate use of analgesics. Sadly, it is impossible to identify these patients according to age, gender, socio-economic group or previous experience of pain or surgery.

Adolescent↗

PubMed1996

Gas leakage and the laryngeal mask airway. A comparison with the tracheal tube and facemask during spontaneous ventilation using a circle breathing system.

The ability of the laryngeal mask airway, tracheal tube and facemask to provide a leak free seal in a clinical setting was assessed by measuring the minimal fresh gas flows needed in a closed circle system during spontaneous ventilation on 60 subjects. The fresh gas flow was reduced until no spillage occurred from the pop-off valve. This fresh gas flow was taken to represent the sum of gas uptake by the subject and gas leakage from the circuit. The median fresh gas flow after 20 minutes was 350 ml.min-1 in the laryngeal mask airway group, 350 ml.min-1 in the tracheal tube group and 450 ml.min-1 in the facemask group. The fresh gas flow required for the facemask group was significantly higher than that for the laryngeal mask airway or tracheal tube groups (p < 0.01). There was no significant difference between the fresh gas flows required for the tracheal tube and laryngeal mask airway group. We conclude that the laryngeal mask airway provides as good a gas tight seal as a tracheal tube in this context and would be of benefit in reducing anaesthetic gas pollution.

Adult↗