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Robert L Chatburn

Publications and source records attributed to Robert L Chatburn.

10 recordsLinked to original sources
PubMed2006

Procedure to normalize data for benchmarking.

INTRODUCTION: The hospital billing system is usually the source for reporting activity counts used in benchmarking efforts. Because billing is associated with a specific procedure, benchmarking data are often reported as procedure-days, procedure-shifts, or procedure-hours. Normalizing (usually to procedure-days) is required when comparing data for benchmarking purposes. For an institution that uses hourly billing, simply dividing procedure-hours by 24 (or procedure-shifts by 2 or 3) will underestimate the procedure-days reported by a daily billing system, because daily billing systems use the convention that any fractional day of service is rounded up to the next higher day. The purposes of this study were: (1) to simulate sets of data and determine the expected error with conversion by simple division, (2) to derive a more accurate procedure for normalizing benchmarking data, and (3) to compare the new normalization procedure to simple division, using simulated and actual data. METHODS: A reference population of simulated patient data was created using a spreadsheet to generate random start times paired with actual procedure durations (eg, hours of mechanical ventilation) for 5,000 patients. The spreadsheet calculated "true" billable procedure-days and procedure-shifts from the simulated procedure-hours. Next, a resampling procedure was used to simulate the effect of submitting benchmarking data based on various numbers of patients. The resulting sets of data were used to examine the association between sample size and conversion error when converting from procedure-hours to procedure-days and to generate an alternative conversion procedure that uses linear regression to estimate procedure-days from procedure-hours. An additional regression equation was generated from actual patient data, using simultaneously recorded procedure-hours and procedure-days. The set of mean conversion errors for the 2 regression equations was compared using the Mann-Whitney rank sum test. RESULTS: In general, conversion errors (both systematic and random errors) were smaller with larger sample sizes and with longer service periods, approaching an asymptote at a sample size greater than about 20. Using division, the conversion errors for a sample size of 100 were +/-16% for hourly reporting, +/-11% for 8-hour shifts, and +/-8% for 12-hour shifts. The regression equations for conversion derived from simulated data were as follows. For hourly billing, procedure-days = +/-0.237 + (0.049) (procedure-hours). For 8-hour shifts, procedure-days = +/-0.205 + (0.372) (procedure-shifts). For 12-hour shifts, procedure-days = +/-0.114 + (0.541) (procedure-shifts). Using those regression equations, the conversion errors for a sample size of 100 were +/-1% for hourly reporting, +/-0.2% for 8-hour shifts, and +/-0.2% for 12-hour shifts. The regression equation (for hourly billing) derived from simulated data gave better results than did the equation derived from actual data (median error 0.39 vs +/-2.92, p = 0.013).

Benchmarking↗
PubMed2006

Nocturnal oxygenation using a pulsed-dose oxygen-conserving device compared to continuous flow.

BACKGROUND: The pulsed-dose oxygen-conserving device (PDOCD) has gained wide acceptance as a tool to reduce the cost and inconvenience of portable oxygen delivery. Despite the widespread use of PDOCDs in awake and ambulating patients, few studies report their use during sleep. This study was designed to compare heart rate and oxygen saturation (measured via pulse oximetry [S(pO2)]) of sleeping patients using one brand of PDOCD versus continuous-flow oxygen. METHODS: We studied 10 home-oxygen patients who were using various continuous-flow oxygen systems and prescriptions. Baseline asleep and awake S(pO2) and heart rate were recorded while the patients used their existing home-oxygen systems (liquid oxygen or oxygen concentrator with nasal cannula) and continuous-flow oxygen prescription. Patients were then switched to a nasal cannula connected to a PDOCD. The PDOCD setting was adjusted to produce an S(pO2) equal to the patient's awake baseline on continuous-flow. This setting was then used while the patient subsequently slept. Mean values for S(pO2) and heart rate and hours of sleep were calculated by the software in the oximeter. Mean values for S(pO2) and heart rate were compared with the paired Student's t test. RESULTS: There was a statistically significant but clinically unimportant S(pO2) difference between the patients who used continuous-flow oxygen and those who used the PDOCD (95.7% vs 93.2%, respectively, p = 0.043). There was no difference in heart rate (77.3 beats/min vs 77.9 beats/min, p = 0.70). The sample size was adequate to detect a difference in heart rate of 5 beats/min at a power of 80%. For the subset of patients whose PDOCD triggering sensitivity was set on sensitive (vs the default lower sensitivity) there was a statistically significant but clinically unimportant S(pO2) difference (continuous-flow 95.6% vs PDOCD 93.2%, p = 0.044). All other comparisons showed no differences, but the samples sizes were too small to make any firm conclusions. One patient experienced an 11% S(pO2) drop with the PDOCD because of an inadequate triggering sensitivity setting. CONCLUSIONS: The PDOCD model we studied was able to deliver oxygen therapy (via nasal cannula) comparable to continuous-flow in 9 of 10 patients. The resting daytime S(pO2) on continuous-flow appears to be an appropriate target for setting the PDOCD to ensure adequate oxygenation, even during sleep, with the PDOCD we tested. We conclude that the PDOCD we tested is able to maintain adequate S(pO2) during sleep in selected patients. Because of differences in design, triggering-signal sensitivity, and oxygen-pulse volume, these results cannot be generalized to all patients or all oxygen-conserving devices. Further research is needed to determine the general performance of PDOCDs on larger populations of oxygen-dependent patients and patients with sleep-disordered breathing.

Female↗
PubMed2004

Advancing beyond the average: the importance of mentoring in professional achievement.

The profession of respiratory care is founded on rigorous scientific research, which in turn depends on rigorous training in research methods. Only a small part of that training is from written and audiovisual materials; the most important aspects of becoming a respiratory researcher are learned from. Becoming a thoroughly-involved respiratory care professional, then a researcher, and then a mentor is challenging but rich with the rewards of contributing to the advancement of science and, thereby, to the care and comfort of our patients. Becoming a respiratory researcher begins with. Only those with a burning desire to excel, to discover truth, and to contribute to the advancement of the profession will persevere through the setbacks and bring a research project to final fruition. The second requirement for long-term success is learning to maintain between enthusiasm and realism. It is crucial to avoid taking on more than you can realistically do, and it is necessary to devote adequate time to your family and/or non-work-related pursuits and recreation. The third aspect of becoming a contributor to respiratory care research is rigorous and ongoing education in the of respiratory care, the methods of medical research, and the basic sciences and mathematics that underlie the profession, including some calculus, engineering physics, and statistics. You must understand research design, critical analysis of research, and numerous aspects of presentation, including clear writing and concise speaking. The fourth aspect is : you must have a strong commitment to obtaining accurate, reproducible, and meaningful data. You must sustain strong attention to detail; mentors are essential because they teach the needed discipline, the required measurement skills, and how to select the appropriate equipment with which to conduct the research. is the fifth aspect. In addition to planning and using your time wisely, you must learn what are realistic expectations about how long a project will take, when to ask for help, and when to stop because you have reached your physical or mental limit and you need to rest and devote some time to your nutrition and recreation. The sixth aspect is : having achieved the basic skills and gained a fair amount of experience, your efficiency improves and you begin to achieve more in a day; you begin to start mentoring others; you can confidently and quickly handle multiple projects; if you don't know the answers you know where to find them; you are seen as an authority and people ask you for consultations and presentations and to participate in committees. The final aspect is, meaning that your practice of respiratory care reaches a level at which you meet challenges for which you feel you have no response in memory and yet you succeed.

Humans↗
PubMed2004

Computer control of mechanical ventilation.

Computer control of mechanical ventilators includes the operator-ventilator interface and the ventilator-patient interface. New ventilation modes represent the evolution of engineering control schemes. The various ventilation control strategies behind the modes have an underlying organization, and understanding that organization improves the clinician's appreciation of the capabilities of various ventilation modes and gives an idea of what we can and should expect for the future. The operator-ventilator interface has received little attention in the literature, despite the fact that there is a whole science of human-computer interaction. This report suggests a methodology for the study of ventilator interfaces.

Artificial Intelligence↗
PubMed2004

Overview of respiratory care research.

Few health care workers are directly involved in conducting research, but all must be able to read and understand scientific reports in medical journals. They must be familiar with the basic concepts of research in order to practice as professionals. The most important skill is the ability to read and critically evaluate published reports. Health care administrators rely on the results of studies to help solve problems and make decisions about important subjects, such as cost containment, productivity assessment, and continuous quality improvement. Educators must stay current with new technology and its evidence base. Both administrators and educators must be familiar with basic research concepts in order to be informed consumers of research information. Research attempts to find answers using the scientific method. This report describes the steps in the scientific method, the overall plan for conducting scientific research, and some basic skills required to successfully conduct research.

Biomedical Research↗
PubMed2003

Performance comparison of two oscillating positive expiratory pressure devices: Acapella versus Flutter.

BACKGROUND: Oscillatory positive expiratory pressure (PEP) with the Flutter device facilitates secretion removal. In the Flutter a steel ball vibrates inside a cone, causing air flow vibration. A new device, the Acapella, uses a counterweighted plug and magnet to create air flow oscillation. The Acapella comes in 2 models: one for patients with expiratory flow > or = 15 L/min and one for < or = 15 L/min. We hypothesized that the Acapella and Flutter would produce similar mean PEP, oscillatory pressure amplitude, and frequency over a clinically relevant range of flows. METHODS: We measured oscillatory amplitude, PEP, and frequency. Values for frequency, peak, trough, and mean pressure were recorded automatically every 3 seconds at flows of 5, 10, 15, 20, 25, and 30 L/min. The pressure waveform for 1 second was also graphically displayed and recorded. The devices were adjusted to give low, medium, and high mean expiratory pressure (Flutter angle at 0, 20, and 40 degrees; Acapella by dial setting). Data were analyzed by 2-way repeated measures analysis of variance, and differences were considered significant when p was < 0.05. RESULTS: There were statistically significant differences between the devices for mean pressure, pressure amplitude, and frequency, for all experimental conditions. However, the differences were relatively small and may not be clinically important. Both devices produced similar pressure waveforms at the medium flows. At 5 L/min the Acapella produced a more stable waveform, with a lower frequency, higher amplitude, and a slightly wider range of PEP than the Flutter. CONCLUSIONS: Acapella and Flutter have similar performance characteristics. Acapella's performance is not gravity-dependent (ie, dependent on device orientation) and may be easier to use for some patients, particularly at low expiratory flows.

Air Pressure↗
PubMed2002

Sudden development of right and left lung asymmetry in a pediatric patient following craniotomy.

A 7-year-old girl presented to the pediatric intensive care unit following a craniotomy that left her with dysphagia, poor cough, and problems with retained secretions. Pulmonary function and blood oxygen saturation worsened for 3 days after surgery. Noninvasive positive-pressure ventilation and increased fraction of inspired oxygen improved oxygenation. Glycopyrrolate was administered to decrease secretions but had little effect. The first chest radiograph showed left lung hyperinflation. The right lung showed loss of volume and elevation of the right hemidiaphragm. There was no mediastinal shift. Another chest radiograph 3 hours later showed substantial improvement. We discuss the causes of acute lung volume asymmetry and possible interpretations of the radiographs.

Cerebral Ventricle Neoplasms↗
PubMed2002

A comparison of intrapulmonary percussive ventilation and conventional chest physiotherapy for the treatment of atelectasis in the pediatric patient.

OBJECTIVE: Compare intrapulmonary percussive ventilation (IPV) to conventional chest physiotherapy (CPT) and determine their effects on improving atelectasis and static compliance in pediatric patients. METHODS: We conducted a retrospective study of 46 patients who received IPV therapy with the Percussionator IPV-1 ventilator at frequencies of 180-220 cycles/min and pressures of 15-30 cm H(2)O. Medicated aerosol therapy with albuterol 2.5 mg in 6 mL normal saline solution was delivered with each IPV treatment. Baseline and subsequent chest radiographs were evaluated by a pediatric radiologist. We used an ordinal scoring system to measure the degree of atelectasis to evaluate chest radiographs (4 = complete collapse, 0 = complete resolution). Then we conducted a prospective, randomized, controlled study of intubated and mechanically ventilated patients to compare changes in atelectasis and static compliance. Baseline and daily chest radiographs were evaluated using the same scoring system as in the retrospective pilot evaluation. Patients were ventilated in the volume-controlled, synchronized intermittent mandatory ventilation mode, with tidal volumes of 6-10 mL/kg. Patients were randomized to CPT (clapping and vibration) or IPV at frequencies of 180-220 cycles/min and pressures of 15-30 cm H(2)O (equal to the peak pressures on the ventilator), with 6 mL of normal saline solution via medicated aerosol. Both treatments were given every 4 h and lasted 10-15 min. Static compliance measurements were calculated from exhaled tidal volumes and plateau pressures. RESULTS: In the retrospective study the median age of patients receiving IPV was 4.2 years and the median duration of IPV was 6.2 days. A change in atelectasis score from 3 to 1 (p < 0.001) was seen. In the randomized, controlled trial the median age of patients was 3.1 years. Atelectasis scores before treatment were comparable between the CPT and IPV groups (median 2.0 for both groups, p = 0.530). Atelectasis scores after treatment were unchanged in the CPT group (median 2.0, p = 0.421) but improved in the IPV group (median 1.0, p = 0.026). Treatment lasted an average of 6.2 days in the CPT group and 2.1 days in the IPV group (p = 0.018). Neither group showed any change in static compliance following treatment. CONCLUSIONS: In the retrospective study a clinically important improvement in atelectasis was seen in patients who received IPV therapy. In the controlled, clinical trial the IPV group showed more clinically important improvement in atelectasis than the CPT group. IPV is a safe and effective method of alternative airway clearance and can be used on patients with artificial airways.

Adolescent↗
PubMed2002

Accuracy of oxygen analyzers at subatmospheric concentrations used in treatment of hypoplastic left heart syndrome.

INTRODUCTION: The immediate survival of infants with hypoplastic left heart syndrome depends on success in achieving several therapeutic goals: (1) maintain patency of the ductus arteriosus, (2) assure adequate mixing of blood at the atrial level, and (3) establish and maintain a balance between systemic and pulmonary blood flow at or near unity. In accomplishing that final goal, various ventilatory strategies have been used to alter the physiologic modifiers of pulmonary vascular resistance and thus maintain balanced circulation, including ventilation with gas of subatmospheric oxygen concentration. However, no data on this subject have been published in the scientific literature, and commercial oxygen analyzers are specified for use within the range of 0.21 to 1.0 fraction of inspired oxygen (F(IO)(2)), leaving the accuracy of hypoxic gas delivery somewhat uncertain. We evaluated the performance of oxygen analyzers below F(IO)(2) 0.21. METHODS: Two commercially available analyzers were studied: the TED-190 (Teledyne) and the Mini-OX III. Five new analyzers of each model were tested. After a 2-point calibration (F(IO)(2) 1.0 and 0.21), all 5 analyzers of the same model were simultaneously exposed to precision-blended gases at 6 different concentrations of oxygen in nitrogen. Steady state was maintained for at least 2 min at each concentration before readings were recorded. Calibration was verified at F(IO)(2) 0.21 between each level. RESULTS: The mean +/- SD error was 0.0013 +/- 0.0021 for the Mini-OX III analyzers and -0.0004 +/- 0.0009 for the Teledyne analyzers. The upper and lower limits of the 95% confidence interval were 0.39% and -0.13% for the Mini-OX III analyzers and 0.07% and -0.15% for the Teledyne analyzers. The maximum difference between measured and known oxygen concentrations was 1% of full scale. CONCLUSIONS: The Mini-OX III and the Teledyne TED-190 provide accurate and reliable F(IO)(2) readings between 0 and 0.21 that are within the manufacturers' specifications for maximum error. These 2 analyzers are therefore acceptable for use in delivering subambient oxygen concentrations. The Mini-OX III displays oxygen concentration to the nearest 0.1% and may be more appropriate for precise control.

Atmospheric Pressure↗