Order this document
Anaesthesia 2002 Aug;57(8):778-817
[Medline record in process]
Model customisation is used to adjust prognostic models by re-calibrating them to obtain more reliable mortality estimates. We used two methods for customising the Simplified Acute Physiology Score II model for 15 511 intensive care patients by altering the logit and the coefficients of the original equation. Both methods significantly improved model calibration, but customising the coefficients was slightly more effective. The Hosmer-Lemeshow chi2-value improved from 306.0 (p< 0.001) before, to 14.5 (p < 0.07) and 23.3 (p < 0.06) after customisation of the coefficients and the logit, respectively. Discrimination was not affected. The standardised mortality ratio for the entire population declined from 1.16 (95% confidence interval: 1.13-1.20, p < 0.001) to 0.99 (95% confidence interval: 0.96-1.02, p < 0.22) after customisation of the coefficients. The uniformity-of-fit for patients grouped by operative status and comorbidities also improved, butremained imperfect for patients stratified by location before intensive care unit admission. Amalgamation of large, regional databases could provide the basis for the re-calibration of standard prognostic models, which could then be used as a national reference system to allow more reliable comparisons of the efficacy and quality of care based on severity adjusted outcome measures.
PMID: 12133092, UI: 22128340
Other Formats: Links:
Anesth Analg 2002 Jul;95(1):192-7, table of contents
Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL 60637, USA. atung@airway.uchicago.edu
A recognized hazard of prolonged endotracheal intubation is progressive airway occlusion resulting from deposition of secretions on the inner surface of the endotracheal tube (ETT). When volume-controlled ventilation is used, progressive ETT occlusion may be detected by monitoring the difference between peak and plateau airway pressures. In pressure-controlled modes, however, inspiratory airway pressures are preset and thus cannot act as a warning indicator. Instead, changes in delivered tidal volumes may aid the diagnosis of ETT occlusion. To determine whether tidal volume monitoring effectively detects progressive ETT occlusion, we mathematically modeled the response of a ventilator operating in pressure-controlled mode to increasing airway resistance. To corroborate our model, we then bench-tested the Siemens 300 and Puritan-Bennett 7200 ventilators by using a test lung and a series of ETTs ranging in size from 9.0 to 3.5 mm inner diameter to simulate progressive occlusion. We found that when pressure-controlled mode was used, progressive ETT occlusion did not reduce delivered tidal volumes until occlusion was nearly complete. We conclude that prolonged use of pressure-controlled mode may allow significant ETT obstruction to build up undetected, risking complete ETT occlusion and complicating the perioperative care of patients ventilated with this mode. IMPLICATIONS: Although increasing airway pressures during volume-controlled ventilation allow early recognition of endotracheal tube (ETT) obstruction, airway pressures with pressure-controlled ventilation are fixed. We found during tests of two intensive care unit ventilators that although ETT obstruction reduces delivered tidal volumes during pressure-controlled ventilation, reductions do not occur until occlusion is advanced.
PMID: 12088967, UI: 22083393
Other Formats:
Ann Intern Med 2002 Jul 16;137(2):110-6
Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA. dbates@partners.org
Administration of the wrong medication is a serious and understudied problem. Because physicians are not directly involved in the drug administration process, they tend to overlook the possibility of adverse drug events and medication errors in their differential diagnoses of patient illnesses or acute deterioration. This article analyzes the case of a patient with iatrogenic hypoglycemia due to administration of the wrong medication: Insulin instead of heparin was used to flush the patient's arterial line. In addition to assessing the results of the institution's "root-cause analysis" of the factors contributing to this particular adverse event and the institution's response, this article reviews the literature on preventing medication errors. Key strategies that might have been helpful in this case include using checklists for common emergency conditions (such as altered level of consciousness) and automated paging for "panic laboratory values," as well as instituting protocols for medication administration. Changing the system of administering medications by bar coding drugs, with checks of the medication, patient, and provider, could have prevented this accident. Finally, organizations need to strive for a "culture of safety" by providing opportunities to discuss errors and adverse events in constructive, supportive environments and by resisting pressure to find a scapegoat.
Publication Types:
PMID: 12118966, UI: 22114205
Crit Care Med 2002 Jun;30(6 Suppl):S369-72
McMaster University, Hamilton, ON, Canada.
Two well-controlled trials were carried out to investigate the effectiveness of intravenous proton pump inhibitors (PPIs) to reduce peptic ulcer rebleeding after successful hemostasis. The results demonstrated that the PPI reduced the rate of rebleeding significantly. The recent availability of the first intravenous PPI formulation in the United States, intravenous pantoprazole, represents an alternative to intravenous histamine-2 receptor antagonists. The results of 16 randomized, controlled trials involving a total of >3,800 patients (1,892 receiving PPIs and 1,911 controls) suggest that bolus administration plus continuous infusion of PPIs is a more effective pharmacotherapy than bolus infusion alone in decreasing both rebleeding and the need for surgery. Optimal effect is achieved with an intravenous 80-mg bolus, followed by continuous infusion of 8 mg/hr for 3 days, after which therapy may be continued with an oral PPI. Intermittent bolus administration yielded a minimal benefit. A difference in mortality rates has not yet been demonstrated.
PMID: 12072664, UI: 22067331
Crit Care Med 2002 Jun;30(6 Suppl):S365-8
Department of Medicine and Emergency Medicine, LSU Health Sciences Center, Shreveport, LA 71130-3932, USA. sconrad@lushsc.edu
Upper gastrointestinal bleeding from peptic ulcers or other nonvariceal causes generally stops spontaneously; if it fails to do so, aggressive management is required. Such measures also are necessary for patients at high risk for rebleeding. Endoscopic therapy achieves hemostasis in >90% of bleeding patients and reduces mortality. After successful hemostasis of the initial bleeding episode, the primary concern becomes the prevention of rebleeding, which occurs in up to 20% of patients. Acid suppression with histamine-2-receptor antagonists has been widely used for many years to prevent recurrent bleeding. However, in acutely bleeding patients, these agents have not been shown to reduce the number of episodes of further bleeding or rebleeding or to reduce the need for transfusions or surgery. Omeprazole, an intravenous proton pump inhibitor, significantly reduced the rate of rebleeding in a recent placebo-controlled trial in which only patients with endoscopic confirmation of successful hemostasis were enrolled. Although this drug does not seem to reduce the need for surgical intervention or to decrease mortality, the trial does indicate the promise of intravenous proton pump inhibitors in reducing upper gastrointestinal bleeding. Evidence from additional well-controlled trials is needed to confirm this finding. The use of proton pump inhibitors in this setting also may have a positive economic impact, and a decrease in the percentage of patients who experience rebleeding will eliminate the cost of further management strategies in those cases.
PMID: 12072663, UI: 22067330
Crit Care Med 2002 Jun;30(6 Suppl):S349-50
Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Health Sciences Center, Denver, CO, USA.
PMID: 12072659, UI: 22067326
Crit Care Nurse 2002 Apr;22(2):16-7
PMID: 11961939, UI: 21958064
Crit Care Nurse 2002 Apr;22(2):134
PMID: 11961938, UI: 21958077
the above reports in Macintosh PC UNIX Text HTML format documents on this page through Loansome Doc