Biomedical subjects

W B Runciman

Publications and source records attributed to W B Runciman.

At least 37 records · Page 2Linked to original sources

PubMed1993

The Australian Incident Monitoring Study: an analysis of 2000 incident reports.

The Australian Patient Safety Foundation was formed in 1987; it was decided to set up and co-ordinate the Australian Incident Monitoring Study as a function of this Foundation; 90 hospitals and practices joined the study. Participating anaesthetists were invited to report, on an anonymous and voluntary basis, any unintended incident which reduced, or could have reduced, the safety margin for a patient. Any incident could be reported, not only those which were deemed "preventable" or were thought to involve human error. The Mark I AIMS form was developed which incorporated features and concepts from several other studies. All the incidents in this symposium were reported using this form, which contains general instructions to the reporter, key words and space for a narrative of the incident, structured sections for what happened (with subsections for circuitry incidents, circuitry involved, equipment involved, pharmacological incidents and airway incidents), why it happened (with subsections for factors contributing to the incident, factors minimising the incident and suggested corrective strategies), the type of anaesthesia and procedure, monitors in use, when and where the incident happened, the experience of the personnel involved, patient age and a classification of patient outcome. Enrollment, reporting and data-handling procedures are described. Data on patient outcome are presented; this is correlated with the stages at which the incident occurred and with the ASA status of the patients. The locations at which the incidents occurred and the types of procedures, the sets of incidents analysed in detail and a breakdown of the incidents due to drugs are also presented.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. Which monitor? An analysis of 2000 incident reports.

The role of monitors in patients undergoing general anaesthesia was studied by analysing the first 2000 incidents reported to the Australian Incident Monitoring Study; 1256 (63%) were considered applicable to this study. In 52% of these a monitor detected the incident first; oximetry (27%) and capnography (24%) detected over half of the monitor detected incidents, the electrocardiograph 19%, blood pressure monitors 12%, a low pressure (circuit) alarm 8%, and the oxygen analyser 4%. Of the other monitors used, 5 first detected 1-2% of incidents, and the remaining 8 less than 0.5% each. The oximeter would have detected over 40% of the monitor detected incidents had its more informative modulated pulse tone always been relied upon instead of the "bleep" of the ECG. A theoretical analysis was then carried out to determine which of an array of 17 monitors would reliably have detected each incident had each monitor been used on its own and had the incident been allowed to evolve. To facilitate "scoring" of monitors, the incidents were categorized empirically into 60 clinical situations; 40% of applicable incidents were accounted for by only 5 clinical situations, 60% by 10 and nearly 80% by 20. 98% were accounted for by the 60 situations. A pulse oximeter, used on its own, would theoretically have detected 82% of applicable incidents (nearly 60% before any potential for organ damage). These figures for capnography are 55% and 43% and for oximetry and capnography combined are 88% and 65%, respectively. With the addition of blood pressure monitoring these become 93% and 65%, and of an oxygen analyser, 95 and 67%. Other monitors, including the ECG, each increase the yield by by less than 0.5%. The international monitoring recommendations and those of the Australian and New Zealand College of Anaesthetists are thoroughly vindicated by the patterns revealed in this study. The priority sequence of monitor acquisition for those with limited resources should be stethoscope, sphygmomanometer, oxygen analyser if nitrous oxide is to be used, pulse oximeter, capnograph, high pressure alarm, and, if patients are to be mechanically ventilated, a low pressure alarm (or spirometer with alarm); an ECG, a defibrillator, a spirometer and a thermometer should be available.

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. The pulse oximeter: applications and limitations--an analysis of 2000 incident reports.

The first 2000 incidents reported to the Australian Incident Monitoring Study were analysed with respect to the role of the pulse oximeter. Of these 184 (9%) were first detected by a pulse oximeter and there were a further 177 (9%) in which desaturation was recorded. Of the 1256 incidents which occurred in association with general anaesthesia 48% were "human detected" and 52% "monitor detected". The pulse oximeter was ranked first and detected 27% of these monitor detected incidents; this figure would have been over 40% if an oximeter had always been used and its more informative modulated pulse tone relied upon instead of that of the "bleep" of the ECG. The pulse oximeter is the "front-line" monitor for endobronchial intubation, the fourth most common incident in association with general anaesthesia (it detected 87% of the 76 cases in which it was in use). It also played an invaluable role as a "back-up" monitor in 40 life-threatening situations in which "front-line" monitors (e.g. oxygen analyser, low pressure alarm, capnograph) were either not in use, were being used incorrectly or failed. Other situations detected, in order of frequency of detection, were: circuit disconnection, circuit leak, desaturation (severe shunt), oesophageal intubation, aspiration and/or regurgitation, pulmonary oedema, endotracheal tube obstruction, severe hypotension, failure of oxygen delivery, hypoxic gas mixture, hypoventilation, anaphylaxis, air embolism, bronchospasm, malignant hyperthermia, and tension pneumothorax.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. The oxygen analyser: applications and limitations--an analysis of 200 incident reports.

The first 2000 incidents reported to the Australian INcident Monitoring Study were analysed with respect to the role of the oxygen analyser; 27 (1%) were first detected by the oxygen analyser. All of these were amongst the 1256 incidents which occurred in association with general anaesthesia, of which 48% were "human detected" and 52% "monitor detected". The oxygen analyser was ranked 7th and detected 4% of these monitor detected incidents. This figure would have been much higher had the oxygen analyser been correctly used on more occasions. The oxygen analyser detected 10 ventilator-driving-gas leaks into the circuit, 6 hypoxic mixtures due to rotameter settings, 3 inappropriate nitrous oxide concentrations, 2 disconnections and 1 leak at the common gas outlet, and 2 partial and 1 total failure of ventilation. In a theoretical analysis of these 1256 incidents it was considered that the oxygen analyser, used on its own, would have detected 114 (9%), had they been allowed to evolve (3% before any potential for organ damage). In 4 incidents an oxygen analyser gave faulty readings, in 3 caused a leak and in one a total circuit obstruction; 5 incidents were not detected because the alarm had been disabled. Despite the advent of piped gas supplies, failure of gas delivery or delivery of a "wrong" gas mixture still occurs surprisingly frequently in current anaesthetic practice; hypoxic mixtures were supplied on 16 occasions, other "wrong" mixtures on 23 and the oxygen supply failed on 7 occasions.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. Crisis management--validation of an algorithm by analysis of 2000 incident reports.

Anaesthetists are called upon to manage complex life-threatening crises at a moment's notice. As there is evidence that this may require cognitive tasking beyond the information-processing capacity of the human brain, it was decided to try and develop a generic crisis management algorithm analogous to the "Phase I" immediate response routine used by airline pilots. Such an algorithm, based on the mnemonic "COVER ABCD, A SWIFT CHECK", was developed and refined over 3 meetings, each attended by 60-100 anaesthetists and aviation psychologists. It was validated against 1301 relevant incidents among the first 2000 incidents reported to the Australian Incident Monitoring Study. It proved sufficiently robust and safe to recommend its general use as an initial response to any incident or crisis which occurs when a patient is breathing gas from an anesthetic machine. It requires a limited knowledge base and is easily learnt and rehearsed during the anaesthetist's working day. It will provide a functional diagnosis in over 99% of cases and will correct 62% of the problems in 40-60 seconds. In the remaining 37% it will allow the anaesthetist to proceed with a "sub-algorithm", confident in the knowledge that some important step has not been missed. In just over 30% of incidents this will be for a problem familiar to all anaesthetists (e.g. laryngospasm, bradycardia); in just over 6% it will be for a less common, more complex, but finite, set of problems (3% cardiac arrest, 1% air embolism, 1% anaphylaxis, 1% for the remaining desaturations); in less than 1% diagnosis and correction will require a more complex checklist (e.g. for malignant hyperthermia, pneumothorax). The next stage, the development of specific sub-algorithms and a structured team approach for ongoing problems, is in progress.

Algorithms↗

PubMed1993

The Australian Incident Monitoring Study. The "wrong drug" problem in anaesthesia: an analysis of 2000 incident reports.

Amongst the first 2000 incidents reported to the Australian Incident Monitoring Study, there were 144 incidents in which the "wrong drug" was nearly or actually administered to a patient. Thirty-three percent of the incidents involved ampoules and just over 40% syringes; in over half of the latter the syringes were of the same size, and also, in over half, they were correctly labelled. In 81% of the 144 incidents the "wrong drug" was actually given. This was more common with syringes (93%) than ampoules (58%). Thus the most common error was actually giving the wrong drug from a correctly labelled syringe. The most common drug involved was a muscle relaxant in both ampoule and syringe incidents. In 74% of all reports, there was the potential for serious harm to the patient; however no deaths were reported. Factors which contributed significantly to the incidents were similar appearance, inattention and haste. "Failure of communication" was a significant factor in syringe incidents when two or more staff were involved. The only significant factor which minimised the outcome was rechecking of the syringe or drug ampoule before giving the drug. Strategies suggested to address the "wrong drug" problem include education of staff about the nature of the problem and the mechanisms involved; colour coding of selected drug classes for both ampoules and syringes; the use of standardised drug storage, layout and selection protocols; having a drawing up and labelling convention; and the use of checking protocols.

Anesthesia↗

PubMed1993

The Australian Incident Monitoring Study. Oesophageal intubation: an analysis of 2000 incident reports.

There were 35 oesophageal intubations in the first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS). These reports confirm existing impressions that misplacement of the endotracheal tube can occur in trained as well as untrained hands, and that auscultation is an unreliable test. On the other hand, the value of capnography is emphasised, with no false positives in the 16 cases in which the instrument was used. There was one false negative. Over the 4 years of the AIMS study, reports have declined in frequency. It is possible that the early detection of oesophageal intubation by capnography has altered its status to the extent that anaesthetists no longer regard it as a "critical" incident. It is highly recommended that the presence of the expected concentration of carbon dioxide in expired air be confirmed by capnography immediately after any endotracheal intubation.

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. Problems with ventilation: an analysis of 2000 incident reports.

A review of the first 2000 incidents reported to the Australian Incident Monitoring Study found 317 incidents which involved problems with ventilation. The major portion (47%) were disconnections; 61% of these were detected by a monitor. Monitor detection was by a low circuit pressure alarm in 37% but this alarm failed to warn of non-ventilation in 12 incidents (in 6 because it was not switched "on" and in 6 because of a failure to detect the disconnection). Failure of detection was usually with ventilator bellows descending in expiration. Complete failure to ventilate occurred in 143 incidents, most commonly because of a disconnection. Disconnection was associated, in one-third of the cases, with interference to the anaesthetic circuit by a third party and in nearly half with surgery on the head and neck. Leaks affected ventilation in 129 incidents, but in only 19 was ventilation totally lost; leaks associated with seal failure of the absorber were common. Misconnections occurred in 36 incidents, most commonly involving the scavenging system. The frequency of a complete failure to check an anaesthetic machine was greater when an induction room was involved than when only the operating theatre was the site of the incident. These incidents suggest that meticulous checking and monitoring for failure of ventilation, preferably using at least two separate, self-activating systems is highly desirable. The Australian and New Zealand College of Anaesthetists' policy on low circuit pressure alarms, oximetry and capnography is vindicated by these reports.

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. Air embolism--an analysis of 2000 incident reports.

There were 19 cases of air embolism (1%) among the first 2000 incidents reported to the Australian Incident Monitoring Study. No embolism-induced fatalities were reported. Serious acute systemic effects occurred in 14 incidents; one circulatory arrest required electrical counter-shock. The surgical field was the entry route for the air in 63% of the incidents; 47% of the cases occurred during head and neck surgery. Capnography was the most successful first detector (26%) and it confirmed the diagnosis in another 26%. Invasive blood pressure monitoring, the electrocardiograph and the pulse oximeter played a useful role in detecting and/or confirming air embolism. Doppler monitoring was not reported in this series. A successful first response for management included head-down posture, manual ventilation, 100% oxygen and control of the air entry site. Cerebral arterial gas embolism may induce vascular endothelial damage and possible delayed neurological sequelae; hyperbaric oxygen therapy should be considered.

Anesthesia↗

PubMed1993

The Australian Incident Monitoring Study. Pneumothorax: an analysis of 2000 incident reports.

Eighteen (1%) of the first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS) involved actual or suspected pneumothoraces; 17 were confirmed. Eleven of the patients were seriously ill beforehand. Four developed tension pneumothoraces, and in 2 incidents (1 tension) the pneumothoraces were bilateral. Nine of the 17 were iatrogenic; 6 (35%) followed neck vein cannulation, and 3 (18%) were surgical complications of tracheotomies. No death was attributed to a pneumothorax. In 8 of the 17 incidents, diagnostic delay or difficulties occurred. Contributing factors identified included urgency, distorted anatomy, failure to check, and haste on the part of the anaesthetist. Desaturation detected by pulse oximetry and hypotension detected by invasive blood pressure monitoring warned the anaesthetist on 2 occasions each. Indications for central vein cannulation or trans-tracheal airway manoeuvres must be firm. Such procedures should always be followed by a closely scrutinised erect chest X-ray as soon as practicable. The possibility of a pneumothorax must always be considered when unexpected cardiorespiratory deterioration occurs.

Anesthesia↗

PubMed1993

The Australian Incident Monitoring Study. Problems with regional anaesthesia: an analysis of 2000 incident reports.

There were 160 incidents associated with regional anaesthesia amongst the first 2000 incidents reported to the Australian Incident Monitoring Study. They were categorised into 6 groups; epidural anaesthesia (83), spinal anaesthesia (42), brachial plexus blocks (14), intravenous local anaesthesia (4), ocular blocks (3), and local infiltration (14). The largest single cause of incidents involved circulatory problems; these occurred in all the groups except brachial plexus block (30 cases of hypotension, 7 of arrhythmias, 3 of cardiac arrest, 2 of hypertension and 1 of myocardial ischaemia). There were 24 drug errors, of which 10 involved the "wrong drug" and 4 "inappropriate use". With the exception of these, all the remainder involved problems specific to regional anaesthesia: 26 inadvertent dural punctures; 19 failed or inadequate blocks; 14 dural puncture headaches (all cured by blood patches); 10 inadvertent total or high spinal blocks (of which 7 required artificial ventilation); 5 blocks on the wrong side or in the wrong patient; 3 late hypoxic incidents and a variety of miscellaneous problems. Three-quarters of all incidents occurred in the presence of an anaesthetist and over 90% in patients of ASA Groups I-III. Rapid recognition by the anaesthetist prevented many potentially life threatening events, and the only death was as a result of surgical bleeding.

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. Patient awareness during anaesthesia: an analysis of 2000 incident reports.

Amongst the first 2000 incidents reported to the Australian Incident Monitoring Study were 16 cases in which patient recall of perioperative events was consistent with awareness. Awareness that occurred in 3 of 10 cases during anaesthesia was attributed to low concentrations of volatile anaesthetic agent; the conduct of anaesthesia appeared to be unremarkable in the other 7. The remaining 6 cases involved the inadvertent paralysis of patients prior to induction of anaesthesia, most commonly by "syringe swap" when suxamethonium was given instead of fentanyl. Some of these patients were significantly distressed. These preliminary findings suggest that incident monitoring should be useful in the study of awareness associated with anaesthesia and the development of strategies to prevent it.

Anesthesia↗

PubMed1993

The Australian Incident Monitoring Study. Paediatric incidents in anaesthesia: an analysis of 2000 incident reports.

The first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS) were analysed to compare anaesthetic incidents in infants and children with those in adults. Of the 2000, 1790 (90%) involved adults, 151 (7%) children and 56 (3%) infants. Healthy children (ASA I) generated a greater proportion of incidents in this group than adults and infants, emphasizing the need for maintaining the same standards for children in this group as for infants and higher risk groups. The AIMS results are similar to those of the United States (US) paediatric "closed claims" studies; the paediatric subset in both the US study and AIMS made up 10% of the total. Also, in both studies, incidents involving the respiratory and breathing circuit systems accounted for nearly half the problems, and cardiovascular problems and problems with the anaesthetic machine each accounted for 10-14% of incidents. In the AIMS study procedures on the head and neck yielded proportionately more incidents in the infant/child group than in the adult group, as did incidents involving the respiratory and breathing circuit systems. Incidents in the child group were often detected clinically; however, there were no differences between the three age groups in the way monitors were used or performed; hence the same monitoring recommendations apply to all groups. Combined oximetry and capnography would have detected nearly 90% of all applicable problems in the AIMS study and could have prevented nearly 90% of the claims arising from inadequate ventilation in the US "closed claims" study.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗

PubMed1993

Evaluation of safety procedures in anaesthesia and intensive care.

A study was conducted to determine the ability of junior anaesthetists to check the anaesthetic machine, demonstrate a knowledge of a multifunction monitor and a defibrillator, and know the hospital fire drill. The subjects were 38 junior anaesthetists working in a large multi-disciplinary teaching hospital. 45% were able to check the anaesthetic machine according to the guidelines of the Australian and New Zealand College of Anaesthetists, and 16% had a complete working knowledge of the monitor. All subjects could use the defibrillator but only 24% could adequately solve the problem of malfunction. Only one subject had a working knowledge of the fire drill; excluding knowledge of the fire drill only 3 subjects (8%) satisfactorily completed all aspects of the assessment. As a result of this study structured checking routines are being introduced into anaesthetic teaching and practice and a similar multi-center study of specialist anaesthetists is being planned.

Anesthesia↗

PubMed1993

The Australian Incident Monitoring Study. Equipment failure: an analysis of 2000 incident reports.

Of the first 2000 incidents reported to the Australian Incident Monitoring Study, 177 (9%) were due to "pure" equipment failure according to pre-defined criteria. Of these 107 (60%) involved anaesthetic equipment, 42 (24%) involved monitors, 17 (10%) other theatre equipment and 11 (6%) the gas or electricity supply. Ninety-seven (55% of the 177) were potentially life-threatening; of these two-thirds would be detected by the array of monitors recommended by the Australian and New Zealand College of Anaesthetists and all but 9 of the remainder would be handled by application of the crisis management algorithm recommended elsewhere in this symposium. Of the 9 remaining, 2 were electrical shock, 3 overheating of a humidifier or blood warmer, 2 the unavailability of a spare laryngoscope and 1 the consequence of a power failure. Meticulous adherence to the equipment checking and monitoring guidelines of the Australian and New Zealand College of Anaesthetists and application of a suitable crisis management algorithm should protect the patient from potentially life-threatening equipment failure in virtually all cases except electric shock, power failure and overheating of warming devices.

Anesthesiology↗

PubMed1993

The Australian Incident Monitoring Study. Human failure: an analysis of 2000 incident reports.

Information of relevance to human failure was extracted from the first 2,000 incidents reported to the Australian Incident Monitoring Study (AIMS). All reports were searched for human factors amongst the "factors contributing," "factors minimising", and "suggested corrective strategies" categories, and these were classified according to the type of human error with which they were associated. In 83% of the reports elements of human error were scored by reporters. "Knowledge-based errors" contributed directly to about one-quarter of incidents; the outcome of one third of incidents was thought to have been minimised by prior experience or awareness of the potential problems, and in one fifth some strategy to improve knowledge was suggested. Correction of "rule-based errors" or provision of protocols or algorithms were thought, together, to have a potential impact on nearly half of all incidents. Failure to check equipment or the patient contributed to nearly one-quarter of all incidents, and inadequate crisis management contributed to a further 1 in 8. "Skill-based errors" (slips and lapses) were directly responsible for 1 in 10 of all incidents, and were thought to make an indirect contribution in up to one quarter. "Technical errors" were responsible for about 1 in 8 incidents. Analysing the relative contribution of each type of error for each type of problem allows the development of rational preventative strategies.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidents↗

PubMed1993

The Australian Incident Monitoring Study. System failure: an analysis of 2000 incident reports.

Although 70-80% of problems have some component of human error, its overall contribution to many problems may be small; studies of complex systems have revealed that up to 85% are primarily due to deficiencies in the lay-out and processes of the system. The anaesthetist has to operate in a complex system; many problems originate from deficiencies in this system. Information of relevance to system failure was extracted from the first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS). A system-based deficiency directly contributed to one-quarter of problems (four-fifths if human factors are included), some aspect of the system minimized the adverse outcome in over half of all cases (four-fifths if human factors are included), and in two-thirds (three-quarters if human factors are included) a system-based strategy would have been helpful; the system was implicated in 90% of all incidents (97% if human factors are included). Regardless of whether or not all human error should be regarded as part of the "system", attempts to modify its incidence and nature have to emanate from the system. AIMS reporting pathways and the organizations involved in developing and implementing strategies to improve the system operate at four levels. Level I involves the use of AIMS reports by hospitals and group practices for audit at a local level. Level II involves AIMS participants sending forms to the AIMS central office; collated information is then sent back to contributors by newsletter. Level III involves interaction between AIMS and the major professional bodies and level IV interaction between AIMS, these bodies and a variety of national and international agencies. Over 100 topics were identified from the AIMS data for consideration at one or more of these levels. AIMS has the potential not only to play a vital practical role in the continued enhancement of the quality of anaesthetic practice, but also to provide a valuable resource for research at the increasingly important interface between human behaviour and complex systems.

Accidents↗

PubMed1993

Commentary on equipment recommendations.

The international standards for safe anaesthesia may all be satisfied with relatively limited resources. General standards deal with clinical and administrative autonomy, peer review, training, clinical practice and the role and working conditions of the anaesthetist. Additional recommendations deal with suggestions for the progressive acquisition of equipment and monitors as resources allow. These include: a light source, thermometer, sphygmomanometer and stethoscope, with an oxygen analyser if nitrous oxide is to be used, and a disconnect alarm if a ventilator is to be used (basic requirements); a low pressure oxygen supply failure alarm, devices mitigating against the supply of hypoxic gas mixtures, oximeter, capnograph, electrocardiograph and defibrillator (highly recommended); a spirometer, neuromuscular junction monitor and electronic thermometer (recommended); and finally devices such as volatile agent monitors and invasive blood pressure monitors for areas with ample resources.

Anesthesiology↗