PubMed Health⌕ Search

Biomedical subjects

D Story

Publications and source records attributed to D Story.

14 recordsLinked to original sources
PubMed2006

Nurses' attitudes to a medical emergency team service in a teaching hospital.

BACKGROUND: Cultural barriers including allegiance to traditional models of ward care and fear of criticism may restrict use of a medical emergency team (MET) service, particularly by nursing staff. A 1-year preparation and education programme was undertaken before implementing the MET at the Austin Hospital, Melbourne, Australia. During the 4 years after introduction of the MET, the programme has continued to inform staff of the benefits of the MET and to overcome barriers restricting its use. OBJECTIVE: To assess whether nurses value the MET service and to determine whether barriers to calling the MET exist in a 400-bed teaching hospital. METHODS: Immediately before hand-over of ward nursing, we conducted a modified personal interview, using a 17-item Likert agreement scale questionnaire. RESULTS: We created a sample of 351 ward nurses and obtained a 100% response rate. This represents 50.9% of the 689 ward nurses employed at the hospital. Most nurses felt that the MET prevented cardiac arrests (91%) and helped manage unwell patients (97%). Few nurses suggested that they restricted MET calls because they feared criticism of their patient care (2%) or criticism that the patient was not sufficiently unwell to need a MET call (10%). 19% of the respondents indicated that MET calls are required because medical management by the doctors has been inadequate; many ascribed this to junior doctors and a lack of knowledge and experience. Despite hospital MET protocol, 72% of nurses suggested that they would call the covering doctor before the MET for a sick ward patient. However, 81% indicated that they would activate the MET if they were unable to contact the covering doctor. In line with hospital MET protocol, 56% suggested that they would make a MET call for a patient they were worried about even if the patient's vital signs were normal. Further, 62% indicated that they would call the MET for a patient who fulfilled MET physiological criteria but did not look unwell. CONCLUSIONS: Nurses in the Austin Hospital value the MET service and appreciate its potential benefits. The major barrier to calling the MET appears to be allegiance to the traditional approach of initially calling parent medical unit doctors, rather than fear of criticism for calling the MET service. A further barrier seems to be underestimation of the clinical significance of the physiological perturbations associated with the presence of MET call criteria.

Adult↗
PubMed2006

Perioperative pulse contour cardiac output analysis in a patient with severe cardiac dysfunction.

We describe a patient with severe left ventricular dysfunction simultaneously monitored with pulse contour cardiac output (PiCCO) analysis, a continuous cardiac output pulmonary artery catheter (continuous COPAC) and intraoperative transoesophageal echocardiography (TOE). There was good agreement between cardiac output (CO) measurements obtained by the three techniques prior to cardiopulmonary bypass (CPB). Agreement of CO measurements following CPB was initially pool; but improved following recalibration of PiCCO. PiCCO-derived global end-diastolic volume index (GEDVI) and cardiac function index (CFI), were assessed as markers of left ventricular preload and myocardial contractility, respectively. GEDVI correlated well with CO in the postoperative period. CFI increased more than two-fold following coronary revascularization and milrinone administration, and there was also a temporal relationship between the CFI and the dose of milrinone in the first 24 hours of treatment. Global end-diastolic volume and cardiac function index may be useful additional measures of left ventricular preload and myocardial contractility in patients with severe left ventricular dysfunction.

Cardiac Output↗
PubMed2006

An introductory guide to survey research in anaesthesia.

Surveys allow convenient and inexpensive research. Surveys include mail-out questionnaires, email questionnaires, telephone interviews, and personal interviews. Despite a widespread perception that surveys are easy to conduct, good surveys need rigorous design, implementation and analysis. This requires substantial planning, time and effort. The most important step in designing a survey is to clearly define the question(s) the survey aims to answer The target population, measured variables and types of associations being investigated should be specific and unambiguous. Investigators should concentrate on what they 'need to know' rather than what would be 'nice to know'. During development surveys should be piloted to identify problems. The main goal when implementing a survey is to maximize the response rate to avoid misleading results. Evidence-based strategies, including brief personalized surveys with stamped return envelopes, can be used to maximize the response rate. A poorly conducted survey can lead to misleading or invalid conclusions and may undermine participation in subsequent surveys by the target population.

Anesthesiology↗
PubMed2005

The pregnant trauma patient.

Trauma is the leading non-obstetric cause of maternal death. Optimal management of the pregnant trauma patient requires a multidisciplinary approach. The anaesthetist and critical care physician play a pivotal role in the entire continuum of fetomaternal care, from initial assessment, resuscitation and intraoperative management, to postoperative care that often involves critical care support and patient transfer. Primary goals are aggressive resuscitation of the mother and maintenance of uteroplacental perfusion and fetal oxygenation by the avoidance of hypoxia, hypotension, hypocapnia, acidosis and hypothermia. Recognizing and understanding the mechanisms of injury, the factors that may predict fetal outcome, and the pathophysiological changes that can result from trauma, will allow early identification and treatment of fetomaternal injury. This in turn should improve morbidity and mortality. A framework for the acute care of the pregnant trauma patient is presented.

Cesarean Section↗
PubMed2000

Role of pump prime in the etiology and pathogenesis of cardiopulmonary bypass-associated acidosis.

BACKGROUND: The development of metabolic acidosis during cardiopulmonary bypass (CPB) is well recognized but poorly understood. The authors hypothesized that the delivery of pump prime fluids is primarily responsible for its development. Accordingly, acid-base changes induced by the establishment of CPB were studied using two types of priming fluid (Haemaccel, a polygeline solution, and Ringer's Injection vs. Plasmalyte 148) using quantitative biophysical methods. METHODS: A prospective, double-blind, randomized trial was conducted at a tertiary institution with 22 patients undergoing CPB for coronary artery bypass surgery. Sampling of arterial blood was performed at three time intervals: before CPB (t1), 2 min after initiation of CPB at full flows (t2), and at the end of the case (t3). Measurements of Na+, K+, Mg2+, Cl-, HCO3-, phosphate, Ca2+, albumin, lactate, and arterial blood gases at each collection point were performed. Results were analyzed in a quantitative manner. RESULTS: Immediately on delivery of pump prime fluids, all patients developed a metabolic acidosis (base excess: 0. 95 mEq/l (t1) to -3.65 mEq/l (t2) (P < 0.001) for Haemaccel-Ringer's and 1.17 mEq/l (t1) to -3.20 mEq/l (t2). The decrease in base excess was the same for both primes (-4.60 vs. -4.37; not significant). However, the mechanism of metabolic acidosis was different. With the Haemaccel-Ringer's prime, the metabolic acidosis was hyperchloremic (Delta Cl-, +9.50 mEq/l; confidence interval, 7.00-11.50). With Plasmalyte 148, the acidosis was induced by an increase in unmeasured anions, most probably acetate and gluconate. The resolution of these two processes was different because the excretion of chloride was slower than that of the unmeasured anions (Delta base excess from t1 to t3 = -1.60 for Haemaccel-Ringer's vs. +1.15 for Plasmalyte 148; P = 0.0062). CONCLUSIONS: Cardiopulmonary bypass-induced metabolic acidosis appears to be iatrogenic in nature and derived from the effect of pump prime fluid on acid-base balance. The extent of such acidosis and its duration varies according to the type of pump prime.

Acid-Base Equilibrium↗
PubMed1989

Evidence for tissue diffusion limitation of VO2max in normal humans.

We recently found [at approximately 90% maximal O2 consumption (VO2max)] that as inspiratory PO2 (PIO2) was reduced, VO2 and mixed venous PO2 (PVO2) fell together along a straight line through the origin, suggesting tissue diffusion limitation of VO2max. To extend these observations to VO2max and directly examine effluent venous blood from muscle, six normal men cycled at VO2max while breathing air, 15% O2 and 12% O2 in random order on a single day. From femoral venous, mixed venous, and radial arterial samples, we measured PO2, PCO2, pH, and lactate and computed mean muscle capillary PO2 by Bohr integration between arterial (PaO2) and femoral venous PO2 (PfvO2). VO2 and CO2 production (VCO2) were measured by expired gas analysis, VO2max averaged 61.5 +/- 6.2 (air), 48.6 +/- 4.8 (15% O2), and 38.1 +/- 4.1 (12% O2) ml.kg-1.min-1. Corresponding values were 16.8 +/- 5.6, 14.4 +/- 5.0, and 12.0 +/- 5.0 Torr for PfVO2; 23.6 +/- 3.2, 19.1 +/- 4.2, and 16.2 +/- 3.5 Torr for PVO2; and 38.5 +/- 5.4, 30.3 +/- 4.1, and 24.5 +/- 3.6 Torr for muscle capillary PO2 (PmCO2). Each of the PO2 variables was linearly related to VO2max (r = 0.99 each), with an intercept not different from the origin. Similar results were obtained when the subjects were pushed to a work load 30 W higher to ensure that VO2max had been achieved. By extending our prior observations 1) to maximum VO2 and 2) by direct sampling of femoral venous blood, we conclude that tissue diffusion limitation of VO2max may be present in normal humans. In addition, since PVO2, PfVO2, and PmCO2 all linearly relate to VO2max, we suggest that whichever of these is most readily obtained is acceptable for further evaluation of the hypothesis.

Adult↗
PubMed1989

Effects of altitude acclimatization on pulmonary gas exchange during exercise.

Pulmonary gas exchange was studied in eight normal subjects both before and after 2 wk of altitude acclimatization at 3,800 m (12,470 ft, barometric pressure = 484 Torr). Respiratory and multiple inert gas tensions, ventilation, cardiac output (Q), and hemoglobin concentration were measured at rest and during three levels of constant-load cycle exercise during both normoxia [inspired PO2 (PIO2) = 148 Torr] and normobaric hypoxia (PIO2 = 91 Torr). After acclimatization, the measured alveolar-arterial PO2 difference (A-aPO2) for any given work rate decreased (P less than 0.02). The largest reductions were observed during the highest work rates and were 24.8 +/- 1.4 to 19.7 +/- 0.8 Torr (normoxia) and 22.0 +/- 1.1 to 19.4 +/- 0.7 Torr (hypoxia). This could not be explained by changes in ventilation-perfusion inequality or estimated O2 diffusing capacity, which were unaffected by acclimatization. However, Q for any given work rate was significantly decreased (P less than 0.001) after acclimatization. We suggest that the reduction in A-aPO2 after acclimatization is a result of more nearly complete alveolar/end-capillary diffusion equilibration on the basis of a longer pulmonary capillary transit time.

Acclimatization↗