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Michael Parr

Publications and source records attributed to Michael Parr.

9 recordsLinked to original sources
PubMed2006

Results from the International Conference of Experts on Intra-abdominal Hypertension and Abdominal Compartment Syndrome. I. Definitions.

OBJECTIVE: Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been increasingly recognized in the critically ill over the past decade. The variety of definitions proposed has led to confusion and difficulty in comparing one study to another. DESIGN: An international consensus group of critical care specialists convened at the second World Congress on Abdominal Compartment Syndrome to standardize definitions for IAH and ACS based upon the current understanding of the pathophysiology surrounding these two syndromes. METHODS: Prior to the conference the authors developed a blueprint for the various definitions, which was further refined both during and after the conference. The present article serves as the final report of the 2004 International ACS Consensus Definitions Conference and is endorsed by the World Society of Abdominal Compartment Syndrome (WSACS). RESULTS: IAH is redefined as an intra-abdominal pressure (IAP) at or above 12 mmHg. ACS is redefined as an IAP above 20 mmHg with evidence of organ dysfunction/failure. ACS is further classified as either primary, secondary, or recurrent based upon the duration and cause of the IAH-induced organ failure. Standards for IAP monitoring are set forth to facilitate accuracy of IAP measurements from patient to patient. CONCLUSIONS: State-of-the-art definitions for IAH and ACS are proposed based upon current medical evidence as well as expert opinion. The WSACS recommends that these definitions be used for future clinical and basic science research. Specific guidelines and recommendations for clinical management of patients with IAH/ACS are published in a separate review.

Abdomen↗
PubMed2005

Guidelines for the uniform reporting of data for Medical Emergency Teams.

It is more than 15 years since the first Medical Emergency Team (MET) system was introduced to identify patients at risk and prevent serious adverse events in Liverpool Hospital, Sydney, Australia. Since then the MET system has been introduced to many other hospitals in Australia and around the world. Standardised and complete reporting of data related to MET activity is increasingly important to identify the role and benefits of the system and to facilitate quality improvement in health care in general. A uniform method for reporting data related to MET activity will aid interpretation of results, comparisons, review and changes to the MET system. The guidelines for uniform reporting of data in relation to MET activities used in our group of hospitals are presented. Future refinement and consensus agreement on the reporting of MET data internationally should enable comparisons between MET systems in several countries.

Australia↗
PubMed2005

TWEAK induces liver progenitor cell proliferation.

Progenitor ("oval") cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors.

Adenoviridae↗
PubMed2004

Continuous intra-abdominal pressure measurement technique.

BACKGROUND: Abdominal compartment syndrome can develop within 12 hours of intensive care unit (ICU) admission in high-risk (shock/trauma, burn, pancreatitis, postabdominal aortic surgery) patients. The current standard of intra-abdominal pressure (IAP) measurement via the urinary catheter is labor intensive, and its intermittent nature could prevent timely recognition of significant changes in IAP. We propose that continuous IAP (CIAP) can be accurately measured via the irrigation port of a three-way catheter and has good agreement with the standard intermittent IAP (IIAP). METHODS: CIAP was prospectively validated by comparing it with IIAP measurement in general surgical and trauma patients admitted to the ICU with a three-way urinary catheter. CIAP was measured via the irrigation port of the three-way catheter transduced to the bedside monitor as a continuous trace without intermittent clamping of the catheter. The standard IIAP measurements were performed via the urine drainage port after clamping the catheter and filling the bladder with 50 mL of 0.9% saline. Each patient had three separate paired measurements performed in standardized manner to compare CIAP with IIAP. Patients' demographics, injury severity, type of surgery, body mass index (BMI), and the paired individual IAP measurements were recorded. The paired measurements were compared using the Bland-Altman (B-A) method for comparing a new clinical measurement with an established one. Data are presented as mean +/- standard error of the mean. RESULTS: During a 6-month period (ending in July 2003), 25 patients were investigated. The mean age was 61.5 +/- 4 years, 66% were men, and BMI was 29.2 +/- 2 kg/m(2). Six patients had vascular surgical, four elective and three urgent general surgical interventions. There were 12 trauma patients with ISS of 23 +/- 2. The CIAP was 14.2 +/- 0.66 (range 2 to 24) mm Hg, and the IIAP was 14.0 +/- 0.68 (range 3 to 24) mm Hg. Seventy-five percent of the measured pairs were exactly the same; in 21%, there was 1 mm Hg difference and in 4% 2 mm Hg. There was no measurement difference greater than 2 mm Hg. The mean difference between the CIAP and IIAP was 0.019 +/- 0.05 mmHg. The B-A statistics revealed that the difference between the means of measurements in each individual patient was between +/-1.96 SD (95% confidence intervals). The B-A scatter plot did not follow any patterns of typical systematic bias. CONCLUSION: CIAP measurement with a three-way urinary catheter is a simple and accurate method for monitoring IAP. It has an excellent agreement with the IIAP over wide pressure ranges and should replace the current labor-intensive intermittent technique.

Abdomen↗
PubMed2004

A comparison of antecedents to cardiac arrests, deaths and emergency intensive care admissions in Australia and New Zealand, and the United Kingdom--the ACADEMIA study.

Many patients have physiological deterioration prior to cardiac arrest, death and intensive care unit (ICU) admission, that are detected and documented by medical and nursing staff. Appropriate early response to detected deterioration is likely to benefit patients. In a multi-centre, prospective, observational study over three consecutive days, we studied the incidence of antecedents (serious physiological abnormalities) preceding primary events (defined as in-hospital deaths, cardiac arrests, and unanticipated ICU admissions) in 90 hospitals (69 United Kingdom [UK]; 19 Australia and 2 New Zealand [ANZ]). 68 hospitals reported primary events during the three-day study period (50 United Kingdom, 16 Australia and 2 New Zealand). Data on the availability of ICU/HDU beds and cardiac arrest teams and Medical Emergency Teams were also collected. Of 638 primary events, there were 308 (48.3%) deaths, 141 (22.1%) cardiac arrests, and 189 (29.6%) unplanned ICU admissions. There were differences in the pattern of primary events between the UK and ANZ (P < 0.001). There were proportionally more deaths in the UK (52.3% versus 35.3%) and a higher number of unplanned ICU admissions in ANZ (47.3% versus 24.2%). Sixty percent (383) of primary events had a total of 1032 documented antecedents. The most common antecedents were hypotension and a fall in Glasgow Coma Scale. The proportion of ICU/HDU to general hospital beds was greater in ANZ (0.034 versus 0.016, P < 0.001) and medical emergency teams were more common in ANZ (70.0% versus 27.5%, P = 0.001). The data confirm antecedents are common before death, cardiac arrest, and unanticipated ICU admission. The study also shows differences in patterns of primary events, the provision of ICU/HDU beds and resuscitation teams, between the UK and ANZ. Future research, focusing upon the relationship between service provision and the pattern of primary events, is suggested.

Adolescent↗
PubMed2002

Clinical examination is an inaccurate predictor of intraabdominal pressure.

This study was designed to establish if clinical examination can accurately predict intraabdominal pressure (IAP). Between August 1998 and March 2000 a prospective blinded observational study of postoperative intensive care unit patients was undertaken at a major trauma center. IAP was measured using an intravesicular technique and compared with clinical evaluation. An IAP of at least 18 mmHg was considered elevated. The sensitivity, specificity, positive predicative value (ppv), negative predictive value (npv), kappa score, and reliability analysis were calculated. A total of 110 patients provided 150 estimates of IAP, which was elevated in 21%. The kappa score was 0.37; sensitivity, 60.9%; specificity, 80.5%; ppv, 45.2%; npv, 88.6%. The mean difference in IAP values between intravesicular readings and clinical estimates was -1.0 +/- 4.1. Prediction of IAP using clinical examination is not accurate enough to replace intravesicular IAP measurements.

Abdominal Injuries↗
PubMed2002

Teaching basic life support skills using self-directed learning, a self-instructional video, access to practice manikins and learning in pairs.

Applying adult learning principles in healthcare education is increasingly recognised as useful and effective. We designed and evaluated an educational package for medical student basic life support (BLS) skills that placed the responsibility of skill acquisition with the learner. The package provided hardcopy and web based information, an in-house produced audio-video tape demonstrating BLS, and open access to manikins in a Skills Centre where the students learnt in pairs. Students determined when they were ready to be assessed. This assessment was performed by two independent observers using the Resuscitation Council (UK) BLS assessment sheet. Two groups, comprising in total 51 fourth year medical students were assessed, 47 were found to be competent in performing BLS on their first assessment. Of the remaining four, three were assessed as competent after further self-directed learning and retesting. Only one student required personal tutoring prior to success. Self-directed learning is a successful method of mastering BLS. Where failure occurred, it was due to inadequate student learning in the Skills Centre. The importance of practice needs emphasis in future use of the programme, as does the virtual guarantee of success, if all steps are followed. A similar programme could be devised for other technical skills.

Audiovisual Aids↗
PubMed2002

Should we follow ATLS guidelines for the management of traumatic pulmonary contusion: the role of non-invasive ventilatory support.

OBJECTIVE: To assess the management of patients with blunt traumatic pulmonary contusion admitted to our hospital. To identify the role of early blood gas analysis, non-invasive ventilation and to assess the validity of the current Advanced Trauma Life Support manual statement that "Patients with significant hypoxia, i.e. PaO(2)<65 mm Hg or 8.6 kPa on room air, SaO(2)<90%, should be intubated and ventilated within the first hour after injury". SETTING: A 24 bed Intensive Care Unit in a major Trauma Centre situated in South Western Sydney, Australia. METHODS: Retrospective review of adults with blunt traumatic pulmonary contusion identified from the trauma registry. RESULTS: A total of 75 patients with an age range of 16-81 years were identified over a 2-year period. Arterial blood gas measurement was available for 32 patients during the immediate resuscitative period (<1 h from admission). All patients received supplemental oxygen and a PaO(2)/FiO(2) ratio was calculated. Seven patients had significant pulmonary contusion, indicated by an initial PaO(2)/FiO(2) ratio of <300, and were treated successfully with non-invasive ventilatory support. A further five patients without arterial blood gas (ABG) analysis on admission but with PaO(2)/FiO(2) ratio of <300 in the ICU were also managed with non-invasive ventilatory support. Multi-modal analgesia was commonly used. CONCLUSIONS: All major trauma patients admitted to our hospital received supplemental oxygen. Interpretation of ABG breathing room air was not used as an indicator for intubation. Most decisions to intubate early were based on clinical need. Patients with significant pulmonary contusion required intubation for reasons other than respiratory failure. Patients with significant pulmonary contusion were managed safely with non-invasive ventilatory support. Further investigation will determine the role of non-invasive ventilatory support in the management of these patients.

Adolescent↗