Hemodynamic Instability during Acute Kidney Injury and Acute Renal Replacement Therapy: Pathophysiology and Clinical Implications.

Hemodynamic instability associated with acute renal replacement therapy (aRRT, HIRRT) and/or with acute kidney injury (AKI) is frequently observed in the intensive care unit; it affects patients' renal recovery, and negatively impacts short- and long-term mortality. A thorough understanding of mechanisms underlying HIRRT and AKI-related hemodynamic instability may allow the physician in adopting adequate strategies to prevent their occurrence and reduce their negative consequences. The aim of this review is to summarize the main alterations occurring in patients with AKI and/or requiring aRRT of those homeostatic mechanisms which regulate hemodynamics and oxygen delivery. In particular, a pathophysiological approach has been used to describe the maladaptive interactions between cardiac output and systemic vascular resistance occurring in these patients and leading to hemodynamic instability. Finally, the potential positive effects of aRRT on these pathophysiological mechanisms and on restoring hemodynamic stability have been described.

CIRSE Standards of Practice on Analgesia and Sedation for Interventional Radiology in Adults.

This CIRSE Standards of Practice document provides best practices for the safe administration of procedural sedation and analgesia for interventional radiology procedures in adults. The document is aimed at health professionals involved in the provision of sedation and analgesia during interventional radiology procedures. The document has been developed by a writing group consisting of physicians with internationally recognised expertise in interventional radiology, and analgesia and sedation.

The Valsalva manoeuvre versus tourniquet for venipuncture.

BACKGROUND: During ultrasound-guided cannulation, venous filling is required for venipuncture. Tourniquet with an elastic tube at the axilla is the most common method to induce venous stasis for cannulation of the deep veins of the arm. Although effective, this method might be associated with short- and long-term complications. Valsalva manoeuvre has been used to produce venous filling in other extrathoracic veins. The aim of this observational study is to demonstrate the effect of Valsalva manoeuvre in respect of the elastic tourniquet on venous distention during echography-guided cannulation of the deep veins of the arm. METHOD: Sixty-nine patients scheduled for cannulation of basilic or brachial vein were prospectively observed. Vein diameters were recorded at rest and after 10 s of Valsalva or tourniquet placement. RESULTS: The mean difference between basilic vein diameters during tourniquet and Valsalva manoeuvre was 0.006 mm (95% confidence interval = -inf, 0.09) with a standard deviation of 0.5 mm (95% confidence interval = 0.5, 0.7; p > 0.01). The mean difference between brachial vein diameters during tourniquet and Valsalva manoeuvre was 0.04 mm (95% confidence interval = -0.23, 0.15) with a standard deviation of 0.8 mm (95% confidence interval = 0.7, 0.9; p > 0.01). DISCUSSION: This increase in cross-sectional basilic and brachial vein diameters was not different to that obtained with the elastic tube tourniquet.

Cardiac output: a central issue in patients with respiratory extracorporeal support.

The iLA-activve® Novalung is a new extracorporeal device specifically designed for lung support in patients with hypercapnic and/or hypoxemic respiratory failure. To date, only low-flow applications for decompensated hypercapnic chronic obstructive pulmonary disease have been reported in the literature. Here, we briefly report three cases of iLA-activve use in patients with hypercapnic-hypoxemic acute lung failure assisted with mid-flow (up to 2.4 L/min) and different single/double venous cannulation. The main findings of our small case series were: firstly, extracorporeal blood flows over 2.0 L/min across the membrane provided clinically satisfying decarboxylation and improved oxygenation; secondly, the ratio between blood flow through the membrane and the patient's cardiac output (CO) was a major determinant for the oxygen increase. The latter could, therefore, be a useful indicator for understanding performance in the complex and multifactorial evaluation of patients with extracorporeal veno-venous lung support.

Follow-up after four-year quality improvement program to prevent inferior limb deep vein thrombosis in intensive care unit.

INTRODUCTION: Deep vein thrombosis (DVT) is a life-threatening complication in intensive care unit (ICU) patients and DVT incidence is used as a marker of quality care. In our ICU an educational program for implementation of DVT prophylaxis and ultrasound screening resulted in a remarkable decrease in DVT incidence which fell from 11.6% to 4.7%. The aim of this paper is to investigate a 4-year long persistent quality improvement of DVT prophylaxis obtained through the implementation of our educational intervention. METHODS: The study was composed of three phases: after the first retrospective investigation of DVT incidence and the evidence of the efficacy of the educational program, this third phase investigates the 2-year long sustainability and persistence in the fall of DVT incidence by the adoption of 1) an electronic form for DVT prophylaxis prescription, 2) a nursing protocol for the application of elastic stokes and 3) a personalized form with a check-list dedicated to DVT prophylaxis. Ultrasound DVT screening was performed twice a week by ICU clinicians. RESULTS: The application of DVT prophylaxis was associated with a very low incidence of DVT (2.6%) not entirely attributable to changes in characteristics of enrolled patients and/or to less intensive DVT ultrasound screening when compared to the preceding phases. Mean mechanical ventilation duration and ICU length of stay were short and similar to those of the second phase and ICU mortality did not change. CONCLUSIONS: The direct involvement of ICU clinicians and nurses in the application of DVT prophylaxis and in DVT diagnosis markedly contributed to maintain a low DVT incidence over time, despite the high turnover of patients.

Time needed to achieve completeness and accuracy in bedside lung ultrasound reporting in intensive care unit.

BACKGROUND: The use of lung ultrasound (LUS) in ICU is increasing but ultrasonographic patterns of lung are often difficult to quantify by different operators. The aim of this study was to evaluate the accuracy and quality of LUS reporting after the introduction of a standardized electronic recording sheet. METHODS: Intensivists were trained for LUS following a teaching programme. From April 2008, an electronic sheet was designed and introduced in ICU database in order to uniform LUS examination reporting. A mark from 0 to 24 has been given for each exam by two senior intensivists not involved in the survey. The mark assigned was based on completeness of a precise reporting scheme, concerning the main finding of LUS. A cut off of 15 was considered sufficiency. RESULTS: The study comprehended 12 months of observations and a total of 637 LUS. Initially, although some improvement in the reports completeness, still the accuracy and precision of examination reporting was below 15. The time required to reach a sufficient quality was 7 months. A linear trend in physicians progress was observed. CONCLUSIONS: The uniformity in teaching programme and examinations reporting system permits to improve the level of completeness and accuracy of LUS reporting, helping physicians in following lung pathology evolution.