Colonização de cateteres venosos centrais por biofilme microbiano

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

Diagnóstico das infecções relacionadas a cateter em recém-nascidos e epidemiologia molecular dos Staphylococcus spp. isolados

Pós-graduação em Biologia Geral e Aplicada - IBB

Simulation-based ultrasound-guided central venous cannulation training program

PURPOSE: To propose a simulation-based ultrasound-guided central venous cannulation skills' training program, during residency.METHODS: This study describes the strategies for learning the ultrasound-guided central venous cannulation on low-fidelity bench models. The preparation of bench models, educational goals, processes of skill acquisition, feedback and evaluation methods were also outlined. The training program was based on key references to the subject.RESULTS: It was formulated a simulation-based ultrasound-guided central venous cannulation teaching program on low-fidelity bench models.CONCLUSION: A simulation-based inexpensive, low-stress, no-risk learning program on low-fidelity bench models was proposed to facilitate acquisition of ultrasound-guided central venous cannulation skills by residents-in-training before exposure to the living patient.

Late-Onset Sepsis in very Low Birth Weight Infants: A Brazilian Neonatal Research Network Study

Background: Late-onset sepsis (LOS) is an important cause of morbidity and mortality in very low birth weight (VLBW) infants.Aim: To determine the incidence, risk factors and etiology of LOS.Methods: LOS was investigated in a multicenter prospective cohort of infants at eight public university neonatal intensive care units (NICUs). Inclusion criteria included inborn, 23-33 weeks of gestational age, 400-1499 g birth weight, who survived >3 days.Results: Of 1507 infants, 357 (24%) had proven LOS and 345 (23%) had clinical LOS. Infants with LOS were more likely to die. The majority of infections (76%) were caused by Gram-positive organisms. Independent risk factors for proven LOS were use of central venous catheter and mechanical ventilation, age at the first feeding and number of days on parenteral nutrition and on mechanical ventilation.Conclusion: LOS incidence and mortality are high in Brazilian VLBW infants. Most risk factors are associated with routine practices at NICU.

Selection of Top 10 Quality Indicators for Nutrition Therapy

Background: The identification of useful quality indicators for nutrition therapy (QINTs) is of great interest and a challenge. This study attempted to identify the 10 QINTs that best suit the practice of quality control in nutrition therapy (NT) by evaluating the opinion of experts in NT with the use of psychometric techniques and statistical tools. Methods: Thirty-six QINTs available for clinical application in Brazil were assessed in 2 distinct phases. In phase 1, 26 nutrition experts ranked QINTs by scoring 4 attributes (utility, simplicity, objectivity, low cost) to assess each QINT on a 5-point Likert scale. The top 10 QINTs were identified from the 10 best scores obtained, and the reliability of expert opinion for each indicator was assessed by Cronbach's alpha. In phase 2, experts provided feedback regarding the selected top 10 QINTs by answering 2 closed questions. Results: The top 10 QINTs, in descending order, are the frequency of nutrition screening of hospitalized patients, diarrhea, involuntary withdrawal of enteral feeding tubes, feeding tube obstruction, fasting longer than 24 hours, glycemic dysfunction, estimated energy expenditure and protein needs, central venous catheter infection, compliance of NT indication, and frequency of application of subjective global assessment. Opinions were consistent among the interviewed experts. During feedback, 96% of experts were satisfied with the top 10 QINTs, and 100% had considered them in accordance with their previous opinion. Conclusion: The top 10 QINTs were identified according to their usefulness in clinical practice by obtaining adequate agreement and representativeness of opinion of nutrition experts. (Nutr Clin Pract. 2012;27:261-267)

Central and peripheral components of exercise-related fatigability in myotonic dystrophy type 1

Fatigue frequently occurs in myotonic dystrophy type 1 (DM1), but its pathophysiology remains unclear. This study assessed central and peripheral components of exercise-related fatigability in patients with DM1, compared to controls.

Central venous pulse pressure analysis using an R-synchronized pressure measurement system

Objective. The information derived from central venous catheters is underused. We developed an EKG-R synchronization and averaging system to obtained distinct CVP waveforms and analyzed components of these. Methods. Twenty-five paralyzed surgical patients undergoing CVP monitoring under mechanical ventilation were studied. CVP and EKG signals were analyzed employing our system, the mean CVP and CVP at end-diastole during expiration were compared, and CVP waveform components were measured using this system. Results. CVP waveforms were clearly visualized in all patients. They showed the a peak to be 1.8+/- 0.7 mmHg, which was the highest of three peaks, and the x trough to be lower than the y trough (-1.6+/- 0.7mmHgand-0.9+/- 0.5mmHg, respectively), withameanpulsepressureof3.4mmHg.ThedifferencebetweenthemeanCVPandCVPatend-diastoleduringexpirationwas0.58+/- 0.81 mmHg. Conclusions. The mean CVP can be used as an index of right ventricular preload in patients under mechanical ventilation with regular sinus rhythm. Our newly developed system is useful for clinical monitoring and for education in circulatory physiology.

Meperidine and skin surface warming additively reduce the shivering threshold: a volunteer study

INTRODUCTION: Mild therapeutic hypothermia has been shown to improve outcome for patients after cardiac arrest and may be beneficial for ischaemic stroke and myocardial ischaemia patients. However, in the awake patient, even a small decrease of core temperature provokes vigorous autonomic reactions-vasoconstriction and shivering-which both inhibit efficient core cooling. Meperidine and skin warming each linearly lower vasoconstriction and shivering thresholds. We tested whether a combination of skin warming and a medium dose of meperidine additively would reduce the shivering threshold to below 34 degrees C without producing significant sedation or respiratory depression. METHODS: Eight healthy volunteers participated on four study days: (1) control, (2) skin warming (with forced air and warming mattress), (3) meperidine (target plasma level: 0.9 mug/ml), and (4) skin warming plus meperidine (target plasma level: 0.9 mug/ml). Volunteers were cooled with 4 degrees C cold Ringer lactate infused over a central venous catheter (rate asymptotically equal to 2.4 degrees C/hour core temperature drop). Shivering threshold was identified by an increase of oxygen consumption (+20% of baseline). Sedation was assessed with the Observer's Assessment of Alertness/Sedation scale. RESULTS: Control shivering threshold was 35.5 degrees C +/- 0.2 degrees C. Skin warming reduced the shivering threshold to 34.9 degrees C +/- 0.5 degrees C (p = 0.01). Meperidine reduced the shivering threshold to 34.2 degrees C +/- 0.3 degrees C (p < 0.01). The combination of meperidine and skin warming reduced the shivering threshold to 33.8 degrees C +/- 0.2 degrees C (p < 0.01). There were no synergistic or antagonistic effects of meperidine and skin warming (p = 0.59). Only very mild sedation occurred on meperidine days. CONCLUSION: A combination of meperidine and skin surface warming reduced the shivering threshold to 33.8 degrees C +/- 0.2 degrees C via an additive interaction and produced only very mild sedation and no respiratory toxicity.

Postoperative sepsis in infants below 6 months of age

BACKGROUND: Sepsis is a threatening postoperative complication especially in small infants. Regarding the advances in perinatal medicine, its incidence is unknown to date. We aimed to investigate the incidence, risk factors, laboratory findings and outcome of postoperative sepsis in infants younger than 6 months old. METHODS: We examined postoperative sepsis in babies below 6 months of age during a 4-year period at a tertiary pediatric institution. RESULTS: The rate of postoperative sepsis was 6.9%. Laparotomy with enterotomy, thoracotomy and diaphragmatic hernia repair (P<0.05, respectively) as well as low postnatal age and long operation time (P<0.001, respectively) were correlated with the incidence of sepsis. Significant independent predictors for the development of sepsis were the presence of a central venous catheter and perioperative antibiotic treatment (P<0.001, respectively). Coagulase negative Staphylococci were the major infecting organism associated with postoperative sepsis, accounting for 53% of monomicrobial infections. Complete blood counts with differential were not different between infants with sepsis and controls, who had undergone the same surgical procedures. Outcome was favorable in all cases; however, the length of hospital stay was significantly longer in sepsis patients (P<0.05). CONCLUSIONS: Postoperative sepsis syndrome is a frequent complication in infants below 6 months of age and causes significant prolongation of hospital stay. Adequate prevention and therapeutic strategies warrant further prospective investigations.

When drugs disappear from the patient: elimination of intravenous medication by hemodiafiltration

Twenty-three hours after heart transplantation, life-threatening acute right heart failure was diagnosed in a patient requiring continuous venovenous hemodiafiltration (CVVHDF). Increasing doses of catecholamines, sedatives, and muscle relaxants administered through a central venous catheter were ineffective. However, a bolus of epinephrine injected through an alternative catheter provoked a hypertensive crisis. Thus, interference with the central venous infusion by the dialysis catheter was suspected. The catheters were changed, and hemodynamics stabilized at lower catecholamine doses. When the effects of IV drugs are inadequate in patients receiving CVVHDF, interference with adjacent catheters resulting in elimination of the drug by CVVHDF should be suspected.

Infection prevention strategies in a stem cell transplant unit: impact of change of care in isolation practice and routine use of high dose intravenous immunoglobulins on infectious complications and transplant related mortality

OBJECTIVE: Nursing in 'live islands' and routine high dose intravenous immunoglobulins after allogeneic hematopoietic stem cell transplantation were abandoned by many teams in view of limited evidence and high costs. METHODS: This retrospective single-center study examines the impact of change from nursing in 'live islands' to care in single rooms (SR) and from high dose to targeted intravenous immunoglobulins (IVIG) on mortality and infection rate of adult patients receiving an allogeneic stem cell or bone marrow transplantation in two steps and three time cohorts (1993-1997, 1997-2000, 2000-2003). RESULTS: Two hundred forty-eight allogeneic hematopoetic stem cell transplantations were performed in 227 patients. Patient characteristics were comparable in the three cohorts for gender, median age, underlying disease, and disease stage, prophylaxis for graft versus host disease (GvHD) and cytomegalovirus constellation. The incidence of infections (78.4%) and infection rates remained stable (rates/1000 days of neutropenia for sepsis 17.61, for pneumonia 6.76). Cumulative incidence of GvHD and transplant-related mortality did not change over time. CONCLUSIONS: Change from nursing in 'live islands' to SR and reduction of high dose to targeted IVIG did not result in increased infection rates or mortality despite an increase in patient age. These results support the current practice.

Access technique and its problems in parenteral nutrition - Guidelines on Parenteral Nutrition, Chapter 9

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7-10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7-10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site.

Hemodynamics and Flow Characteristics of a New Dialysis Port

Renal replacement therapy by hemodialysis requires a permanent vascular access. Implantable ports offer a potential alternative to standard vascular access strategies although their development is limited both in number and extent. We explored the fluid dynamics within two new percutaneous bone-anchored dialysis port prototypes, both by in vitro experiments and computer simulation. The new port is to be fixed to bone and allows the connection of a dialysis machine to a central venous catheter via a built-in valve. We found that the pressure drop induced by the two ports was between 20 and 50 mmHg at 500 ml/min, which is comparable with commercial catheter connectors (15–80 mmHg). We observed the formation of vortices in both geometries, and a shear rate in the physiological range (<10,000s-1), which is lower than maximal shear rates reported in commercial catheters (up to 13,000s-1). A difference in surface shear rate of 15% between the two ports was obtained.