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Anthony P Morton

Publications and source records attributed to Anthony P Morton.

8 recordsLinked to original sources
PubMed2004

Cumulative sum control charts for assessing performance in arterial surgery.

BACKGROUND: The Melbourne Vascular Surgical Association (Melbourne, Australia) undertakes surveillance of mortality following aortic aneurysm surgery, patency at discharge following infrainguinal bypass and stroke and death following carotid endarterectomy. Quality improvement protocol employing the Deming cycle requires that the system for performing surgery first be analysed and optimized. Then process and outcome data are collected and these data require careful analysis. There must be a mechanism so that the causes of unsatisfactory outcomes can be determined and a good feedback mechanism must exist so that good performance is acknowledged and unsatisfactory performance corrected. A simple method for analysing these data that detects changes in average outcome rates is available using cumulative sum statistical control charts. METHODS: Data have been analysed both retrospectively from 1999 to 2001, and prospectively during 2002 using cumulative sum control methods. A pathway to deal with control chart signals has been developed. RESULTS: The standard of arterial surgery in Victoria, Australia, is high. In one case a safe and satisfactory outcome was achieved by following the pathway developed by the audit committee. CONCLUSION: Cumulative sum control charts are a simple and effective tool for the identification of variations in performance standards in arterial surgery. The establishment of a pathway to manage problem performance is a vital part of audit activity.

Algorithms↗
PubMed2004

A PCR method for the identification of methicillin-resistant Staphylococcus aureus (MRSA) from screening swabs.

AIM: The aim of this study was to assess the discriminatory power and potential turn around time (TAT) of a PCR-based method for the detection of methicillin-resistant Staphylococcus aureus (MRSA) from screening swabs. METHODS: Screening swabs were examined using the current laboratory protocol of direct culture on mannitol salt agar supplemented with oxacillin (MSAO-direct). The PCR method involved pre-incubation in broth for 4 hours followed by a multiplex PCR with primers directed to mecA and nuc genes of MRSA. The reference standard was determined by pre-incubation in broth for 4 hours followed by culture on MSAO (MSAO-broth). RESULTS: A total of 256 swabs was analysed. The rates of detection of MRSA using MSAO-direct, MSAO-broth and PCR were 10.2, 13.3 and 10.2%, respectively. For PCR, the sensitivity, specificity, positive predictive value and negative predictive values were 66.7% (95%CI 51.9-83.3%), 98.6% (95%CI 97.1-100%), 84.6% (95%CI 76.2-100%) and 95.2% (95%CI 92.4-98.0%), respectively, and these results were almost identical to those obtained from MSAO-direct. The agreement between MSAO-direct and PCR was 61.5% (95%CI 42.8-80.2%) for positive results, 95.6% (95%CI 93.0-98.2%) for negative results and overall was 92.2% (95%CI 88.9-95.5%). CONCLUSIONS: (1) The discriminatory power of PCR and MSAO-direct is similar but the level of agreement, especially for true positive results, is low. (2) The potential TAT for the PCR method provides a marked advantage over conventional methods. (3) Further modifications to the PCR method such as increased broth incubation time, use of selective broth and adaptation to real-time PCR may lead to improvement in sensitivity and TAT.

Animals↗
PubMed2003

Monitoring the evolutionary process of quality: risk-adjusted charting to track outcomes in intensive care.

OBJECTIVE: To present graphical procedures for prospectively monitoring outcomes in the intensive care unit. DESIGN: Observational study: risk-adjusted control chart analysis of a case series. SETTING: Tertiary referral adult intensive care unit: Princess Alexandra Hospital, Brisbane, Australia. PATIENTS: A total of 3398 intensive care unit admissions from January 1, 1995, to January 1, 1998. CONCLUSIONS: Risk-adjusted process control charting procedures for continuous monitoring of intensive care unit outcomes are proposed as quality management tools. A modified Shewhart p chart and cumulative sum process control chart, using the Acute Physiology and Chronic Health Evaluation III model mortality prediction for risk adjustment, are presented. The risk-adjusted p chart summarizes performance at arbitrary intervals and plots observed against predicted mortality rate to detect large changes in risk-adjusted mortality. The risk-adjusted cumulative sum procedure is a likelihood-based scoring method that adjusts for estimated risk of death, accumulating evidence from outcomes of all previous patients. It formally tests the hypothesis of a change in the odds of death. In this application, we detected a decrease from above to predicted risk-adjusted mortality. This was temporally related to increased senior staffing levels and enhanced ongoing multidisciplinary review of practice, quality improvement, and educational activities. Formulas and analyses are provided as appendices.

Adult↗