Frederick J. Tasota

Mobility interventions to improve outcomes in patients undergoing prolonged mechanical ventilation: a review of the literature.

Survivors of critical illness often undergo an extended recovery trajectory. Reduced functional ability is one of several adverse outcomes of prolonged bed rest and mechanical ventilation during critical illness. Skeletal muscle weakness is known to be one of the major phenomena that account for reduced functional ability. Although skeletal muscle weakness is evident after prolonged mechanical ventilation (PMV), few studies have tested the benefits of various types of mobility interventions in this population. The purpose of this article is to review the published research on improving mobility outcomes in patients undergoing PMV. For this review, published studies were retrieved from MEDLINE, PubMed, CINAHL, and the Cochrane Database of Systematic Reviews from January 1990 to July 2007. A total of 10 relevant articles were selected that examined the effect of whole body physical therapy, electrical stimulation (ES), arm exercise, and inspiratory muscle training (IMT). Overall, there is support for the ability of mobility interventions to improve outcomes in patients on PMV but limited evidence of how to best accomplish this goal. Generating more data from multicenter studies and randomized controlled trials is recommended.

Nursing implications for prevention of adverse drug events in the intensive care unit.

Adverse drug events are common in the intensive care unit setting. Despite the existence of many long-standing safety principles (such as the “five rights”) and new mechanisms to promote medication safety, there is still a gap between practice and the goal of patient safety. This is the result of the many human and system factors that impact care delivery. Research supports the role of the nurse as having a positive impact on patient outcomes. Future research requires the evaluation of new strategies and technologies to support safe medication administration. For example, patient simulation is being used to teach student and novice nurses principles of medication administration in a “safe” setting that more closely resembles the clinical environment. The Institute of Nursing repeatedly has stressed the need to address the organizational, technical, and human issues that impact patient safety, with an emphasis on the need to transform the nurse work environment to keep patients safe. This transformation will require a new level of interdisciplinary research and nursing involvement to address better care for our patients and, in particular, reduce adverse drug events.

Terminal Weaning from Mechanical Ventilation: Planning and Process

There are two major goals of critical care: (1) to save those with a chance to live and (2) to help patients who are dying have a peaceful and dignified death. If reversal of the disease process is not possible and the patient is experiencing substantial pain and suffering, goals need to be reviewed and potentially redefined. These new goals may be to remove unwanted or nonbeneficial therapy, to provide death with dignity, and to support the family. This article details aspects of the decision-making process regarding withdrawal of mechanical ventilation, including ethical principles; decision-making for autonomous patients and non-autonomous patients; advance directives; planning withdrawal of support; terminal weaning methods; patient comfort; family support; and future directions for research, practice, and education.

Auto-positive end-expiratory pressure during tracheal gas insufflation : Testing a hypothetical model

ObjectiveThe major benefit of tracheal gas insufflation (TGI) is an increase in CO2 elimination efficiency by removal of CO2 from the anatomical deadspace. In conjunction with mechanical ventilation, TGI may also alter variables that affect CO2 elimination, such as minute ventilation and peak airway pressure (peak Paw) and cause the development of auto–positive end-expiratory pressure (auto-PEEP). We tested the hypothesis that TGI-induced auto-PEEP alters ventilatory variables. We predicted that TGI-induced auto-PEEP offsets the beneficial effects of TGI on CO2 elimination and that keeping total PEEP (ventilator PEEP + auto-PEEP) constant enhances the CO2 elimination efficiency afforded by TGI. DesignProspective study of two series of patients with acute respiratory distress syndrome receiving mechanical ventilation. SettingIntensive care units at a university medical center. PatientsEach series consisted of eight sequential hypercapnic patients. InterventionsIn series 1, we examined the effect of continuous TGI at 0 and 10 L/min on Paco2, without compensating for the development of auto-PEEP. In series 2, we examined this same effect of continuous TGI while reducing ventilator PEEP to keep total PEEP constant. TGI-induced auto-PEEP was calculated based on dynamic compliance measurements during zero TGI flow conditions (&Dgr;V/&Dgr;P) after averaging the two baseline values for peak Paw and tidal volume and assuming compliance did not change between the zero TGI and TGI flow conditions (&Dgr;VTGI/&Dgr;PTGI). Measurements and Main ResultsIn series 1, total PEEP increased from 13.2 ± 3.2 cm H2O to 17.8 ± 3.5 cm H2O without compensation for auto-PEEP (p = .01). Paco2 decreased (p = .03) from 56.2 ± 10.6 mm Hg (zero TGI) to 52.9 ± 9.3 mm Hg (TGI at 10 L/min), a 6% decrement. In series 2, total PEEP was unchanged (p = NS). Paco2 decreased (p = .03) from 59.5 ± 10.4 mm Hg (zero TGI) to 52.2 ± 8.3 mm Hg (TGI at 10 L/min), a 12% decrement. There was no significant change in Pao2; there were no untoward hemodynamic effects in either series. ConclusionsThese data are consistent with the hypothesis that mechanical ventilation + TGI causes an increase in auto-PEEP that can blunt CO2 elimination. In addition to the ventilator modifications necessary to keep ventilatory variables constant when TGI is used, it is also necessary to reduce ventilator PEEP to keep total PEEP constant and further enhance CO2 elimination efficiency.

Tracheal gas insufflation improves ventilatory efficiency during methacholine-induced bronchospasm

INTRODUCTION Barotrauma and cardiovascular insufficiency are frequently encountered problems in patients with acute bronchospastic disease who require mechanical ventilation. Permissive hypercapnia is a recognized strategy for minimizing these adverse effects; however, it has potential risks. Tracheal gas insufflation (TGI) has been shown to increase carbon dioxide elimination efficiency and thus could permit mechanical ventilation at lower peak airway pressures without inducing hypercapnia. However, caution exists as to the impact of TGI on lung volumes, given that expiratory flow limitation is a hallmark of bronchospastic disease. PURPOSE To examine these issues, we studied ventilatory and hemodynamic effects of continuous TGI as an adjunct to mechanical ventilation before and after methacholine-induced bronchospasm. MATERIALS AND METHODS Ten anesthetized, paralyzed dogs were ventilated on volume-controlled mechanical ventilation during administration of continuous TGI (0, 2, 6, and 10 L/min) while total inspired minute ventilation (ventilator-derived minute ventilation plus TGI) was kept constant. In an additional step, with TGI flow of 10 L/min, total inspired minute ventilation was decreased by 30%. RESULTS PaCO2 decreased (44 +/- 7 mm Hg at zero flow to 34 +/- 7 mm Hg at 6 L/min and 31 +/- 6 mm Hg at 10 L/min, respectively, P < .05), as did the dead space to tidal volume ratio at TGI of 6 and 10 L/min compared with zero flow. There were no significant changes in end-expiratory transpulmonary pressure, mean arterial pressure, or cardiac output. During the highest TGI flow (10 L/min), with a 30% reduction of total inspired minute ventilation, both PaCO2 and peak airway pressure remained less than during zero flow conditions. CONCLUSION We conclude that TGI increases carbon dioxide elimination efficiency during constant and decreased minute ventilation conditions without any evidence of hyperinflation or hemodynamic instability during methacholine-induced bronchospasm.

Assessing renal function.

The kidney has several functions, including the excretion of water, soluble waste (eg, urea and creatinine) and foreign materials (eg, drugs). It is responsible for the composition and volume of circulating fluids with respect to water and electrolyte balance and acid-base status. It has an endocrine function playing a part in the production of vitamin D and erythropoietin and as part of the renin/angiotensin/aldosterone axis. Measurements of renal function rely on measuring, in various ways the degree to which the kidney is successful in these roles.

Keeping an eye on calcium levels.

www.nursingcenter.com MARY ZAMORA, 76, is admitted to your unit after reporting lethargy, constipation, and flank pain. Her daughter tells you that she has metastatic bone cancer, and you also discover that she’s dehydrated. A blood test reveals that she has a total serum calcium of 12.2 mg/dl and abnormally low levels of phosphorous and albumin. Let’s examine how these levels relate to Mrs. Zamora’s condition. When we think of calcium, we first think of its effect on bone health, but it also plays a key role throughout the body. Although 99% of the body’s calcium is stored in bones, the 1% in the bloodstream is what provides a patient’s calcium profile. Looking closely at your patient’s serum calcium level, you can learn important information about her condition.

Predicting heart disease with C-reactive protein.

www.nursingcenter.com ALTHOUGH LIPID profiles help determine a patient’s risk of cardiovascular disease (CVD), favorable levels can be misleading: 50% of patients who experience myocardial infarctions (MIs) have normal levels of low-density and highdensity lipoproteins and triglycerides. Now researchers have found that C-reactive protein (CRP), a naturally occurring substance that rises in response to inflammation, is the leading inflammatory marker for CVD in certain patients. Inflammation plays a significant role in atherosclerosis development, causing plaque to rupture and activating a clotting cascade that can result in MI or stroke. Researchers are exploring whether infectious bacteria or viruses might cause or contribute to inflammation.

Preparing for bronchoscopy.

What is a bronchoscopy? A bronchoscopy is a procedure involving the use of a bronchoscope, a lighted, flexible tube about the thickness of a pencil. The doctor will pass the tube through your nose or sometimes your mouth, into the airways of your lungs. The procedure allows the doctor to look at the airways for anything not normal. The tube may cause a slight discomfort to your nose and throat and may cause coughing. The doctor may take samples for laboratory study. This procedure will provide your doctor with information to help decide on the best treatment plan for you.