Increasing support by nasal high flow acutely modifies the ROX index in hypoxemic patients: A physiologic study.

The ROX (Respiratory rate-OXygenation) index is an early predictor of failure of nasal high flow (NHF), with lower values indicating higher risk of intubation. We measured the ROX index at set flow rate of 30 and 60 l/min in 57 hypoxemic patients on NHF. Patients with increased ROX index values at higher flow (n = 40) showed worse baseline oxygenation, higher respiratory rate and lower ROX index in comparison to patients with unchanged or decreased ROX index values (n = 17). The ROX index variation between flows was correlated with the change in end expiratory lung volume. Set flow rate during NHF might impact the ROX index value.

Quality of Life and Lung Function in Survivors of Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome.

BACKGROUND: Survivors of acute respiratory distress syndrome (ARDS) have long-term impairment of pulmonary function and health-related quality of life, but little is known of outcomes of ARDS survivors treated with extracorporeal membrane oxygenation. The aim of this study was to compare long-term outcomes of ARDS patients treated with or without extracorporeal membrane oxygenation. METHODS: A prospective, observational study of adults with ARDS (January 2013 to December 2015) was conducted at a single center. One year after discharge, survivors underwent pulmonary function tests, computed tomography of the chest, and health-related quality-of-life questionnaires. RESULTS: Eighty-four patients (34 extracorporeal membrane oxygenation, 50 non-extracorporeal membrane oxygenation) were studied; both groups had similar characteristics at baseline, but comorbidity was more common in non-extracorporeal membrane oxygenation (23 of 50 vs. 4 of 34, 46% vs. 12%, P < 0.001), and severity of hypoxemia was greater in extracorporeal membrane oxygenation (median PaO2/FIO2 72 [interquartile range, 50 to 103] vs. 114 [87 to 133] mm Hg, P < 0.001) and respiratory compliance worse. At 1 yr, survival was similar (22/33 vs. 28/47, 66% vs. 59%; P = 0.52), and pulmonary function and computed tomography were almost normal in both groups. Non-extracorporeal membrane oxygenation patients had lower health-related quality-of-life scores and higher rates of posttraumatic stress disorder. CONCLUSIONS: Despite more severe respiratory failure at admission, 1-yr survival of extracorporeal membrane oxygenation patients was not different from that of non-extracorporeal membrane oxygenation patients; each group had almost full recovery of lung function, but non-extracorporeal membrane oxygenation patients had greater impairment of health-related quality of life.

Enteral versus intravenous approach for the sedation of critically ill patients: a randomized and controlled trial.

BACKGROUND: ICU patients must be kept conscious, calm, and cooperative even during the critical phases of illness. Enteral administration of sedative drugs might avoid over sedation, and would be as adequate as intravenous administration in patients who are awake, with fewer side effects and lower costs. This study compares two sedation strategies, for early achievement and maintenance of the target light sedation. METHODS: This was a multicenter, single-blind, randomized and controlled trial carried out in 12 Italian ICUs, involving patients with expected mechanical ventilation duration > 72 h at ICU admission and predicted mortality > 12% (Simplified Acute Physiology Score II > 32 points) during the first 24 h on ICU. Patients were randomly assigned to receive intravenous (midazolam, propofol) or enteral (hydroxyzine, lorazepam, and melatonin) sedation. The primary outcome was percentage of work shifts with the patient having an observed Richmond Agitation-Sedation Scale (RASS) = target RASS ±1. Secondary outcomes were feasibility, delirium-free and coma-free days, costs of drugs, length of ICU and hospital stay, and ICU, hospital, and one-year mortality. RESULTS: There were 348 patients enrolled. There were no differences in the primary outcome: enteral 89.8% (74.1-100), intravenous 94.4% (78-100), p = 0.20. Enteral-treated patients had more protocol violations: n = 81 (46.6%) vs 7 (4.2%), p < 0.01; more self-extubations: n = 14 (8.1%) vs 4 (2.4%), p = 0.03; a lighter sedative target (RASS = 0): 93% (71-100) vs 83% (61-100), p < 0.01; and lower total drug costs: 2.39 (0.75-9.78) vs 4.15 (1.20-20.19) €/day with mechanical ventilation (p = 0.01). CONCLUSIONS: Although enteral sedation of critically ill patients is cheaper and permits a lighter sedation target, it is not superior to intravenous sedation for reaching the RASS target. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01360346 . Registered on 25 March 2011.

A family information brochure and dedicated website to improve the ICU experience for patients' relatives: an Italian multicenter before-and-after study.

PURPOSE: Good communication between ICU staff and patients' relatives may reduce the occurrence of post-traumatic stress disorder, anxiety or depression, and dissatisfaction with clinicians. An information brochure and website to meet relatives' needs were designed to explain in technical yet simple terms what happens during and after an ICU stay, to legitimize emotions such as fear, apprehension, and suffering, and to improve cooperation with relatives without increasing staff workload. The main outcomes were improved understanding of prognosis and procedures, and decrease of relatives' anxiety, depression, and stress symptoms. METHODS: In this prospective multicenter before-and-after study, a self-administered questionnaire was used to investigate relatives' understanding of prognosis, treatments, and organ dysfunction, families' satisfaction, and symptoms of anxiety, depression, and post-traumatic stress. RESULTS: A total of 551 relatives received questionnaires in nine Italian ICUs; 332 (60%) responded, 144 before and 179 after implementation of the brochure and website. Of the 179 relatives who responded after, 131 (73%) stated they had read the brochure and 34 (19%) reported viewing the website. The intervention was associated with increased correct understanding of the prognosis (from 69 to 84%, p = 0.04) and the therapeutic procedures (from 17 to 28%, p = 0.03). Multivariable analysis, together with non-modifiable factors (relative's gender, education level, relationship to patient, and patient status at ICU discharge), showed the intervention to be significantly associated with a lower incidence of post-traumatic stress symptoms (Poisson coefficient = -0.29, 95% CI -0.52/-0.07). The intervention had no effect on the prevalence of symptoms of anxiety and depression. CONCLUSION: An information brochure and website designed to meet relatives' needs improved family members' comprehension and reduced their prevalence of stress symptoms.

Neurological assessment with validated tools in general ICU: multicenter, randomized, before and after, pragmatic study to evaluate the effectiveness of an e-learning platform for continuous medical education.

BACKGROUND: International guidelines recommend systematic assessment of pain, agitation/sedation and delirium with validated scales for all ICU patients. However, these evaluations are often not done. We have created an e-learning training platform for the continuous medical education, and assessed its efficacy in increasing the use of validated tools by all medical and nursing staff of the participating ICUs during their daily practice. METHODS: Multicenter, randomized, before and after study. The eight participating centers were randomized in two groups, and received training at different times. The use of validated tools (Verbal Numeric Rating or Behavioral Pain Scale for pain; Richmond Agitation-Sedation Scale for agitation; Confusion Assessment Method for the ICU for delirium) was evaluated from clinical data recorded in medical charts during a week, with follow-up up to six months after the training. All the operators were invited to complete a questionnaire, at baseline and after the training. RESULTS: Among the 374 nurses and physicians involved, 140 (37.4%) completed at least one of the three courses. The assessment of pain (38.1 vs. 92.9%, P<0.01) and delirium (0 vs. 78.6%, P<0.01) using validated tools significantly increased after training. Observation in the follow-up showed further improvement in delirium monitoring, with no signs of extinction for pain and sedation/agitation measurements. CONCLUSIONS: This e-learning program shows encouraging effectiveness, and the increase in the use of validated tools for neurological monitoring in critically ill patients lasts over time.

Oxygen consumption is depressed in patients with lactic acidosis due to biguanide intoxication.

INTRODUCTION: Lactic acidosis can develop during biguanide (metformin and phenformin) intoxication, possibly as a consequence of mitochondrial dysfunction. To verify this hypothesis, we investigated whether body oxygen consumption (VO2), that primarily depends on mitochondrial respiration, is depressed in patients with biguanide intoxication. METHODS: Multicentre retrospective analysis of data collected from 24 patients with lactic acidosis (pH 6.93 +/- 0.20; lactate 18 +/- 6 mM at hospital admission) due to metformin (n = 23) or phenformin (n = 1) intoxication. In 11 patients, VO2 was computed as the product of simultaneously recorded arterio-venous difference in O2 content [C(a-v)O2] and cardiac index (CI). In 13 additional cases, C(a-v)O2, but not CI, was available. RESULTS: On day 1, VO2 was markedly depressed (67 +/- 28 ml/min/m2) despite a normal CI (3.4 +/- 1.2 L/min/m2). C(a-v)O2 was abnormally low in both patients either with (2.0 +/- 1.0 ml O2/100 ml) or without (2.5 +/- 1.1 ml O2/100 ml) CI (and VO2) monitoring. Clearance of the accumulated drug was associated with the resolution of lactic acidosis and a parallel increase in VO2 (P < 0.001) and C(a-v)O2 (P < 0.05). Plasma lactate and VO2 were inversely correlated (R2 0.43; P < 0.001, n = 32). CONCLUSIONS: VO2 is abnormally low in patients with lactic acidosis due to biguanide intoxication. This finding is in line with the hypothesis of inhibited mitochondrial respiration and consequent hyperlactatemia.

Lung opening and closing during ventilation of acute respiratory distress syndrome.

RATIONALE: The effects of high positive end-expiratory pressure (PEEP) strictly depend on lung recruitability, which varies widely during acute respiratory distress syndrome (ARDS). Unfortunately, increasing PEEP may lead to opposing effects on two main factors potentially worsening the lung injury, that is, alveolar strain and intratidal opening and closing, being detrimental (increasing the former) or beneficial (decreasing the latter). OBJECTIVES: To investigate how lung recruitability influences alveolar strain and intratidal opening and closing after the application of high PEEP. METHODS: We analyzed data from a database of 68 patients with acute lung injury or ARDS who underwent whole-lung computed tomography at 5, 15, and 45 cm H(2)O airway pressure. MEASUREMENTS AND MAIN RESULTS: End-inspiratory nonaerated lung tissue was estimated from computed tomography pressure-volume curves. Alveolar strain and opening and closing lung tissue were computed at 5 and 15 cm H(2)O PEEP. In patients with a higher percentage of potentially recruitable lung, the increase in PEEP markedly reduced opening and closing lung tissue (P < 0.001), whereas no differences were observed in patients with a lower percentage of potentially recruitable lung. In contrast, alveolar strain similarly increased in the two groups (P = 0.89). Opening and closing lung tissue was distributed mainly in the dependent and hilar lung regions, and it appeared to be an independent risk factor for death (odds ratio, 1.10 for each 10-g increase). CONCLUSIONS: In ARDS, especially in patients with higher lung recruitability, the beneficial impact of reducing intratidal alveolar opening and closing by increasing PEEP prevails over the effects of increasing alveolar strain.

Reduced tidal volumes and lung protective ventilatory strategies: where do we go from here?

Three major determinants of lung injury associated with mechanical ventilation have been clearly identified: high pressure/high volume, the shear forces caused by intratidal collapse and decollapse leading to barotrauma/volotrauma/biotrauma. The lung protective strategy aims to reduce the impact of all three determinants. A groundbreaking study showed that reduced tidal volume is less dangerous than high tidal volume, but the researchers did not apply "full" lung protective strategy and did not take into account the shear forces. "Full" protective lung strategy was tested in only one study and in a limited number of patients. Several physiologic studies strongly suggest the advantages of the lung protective strategy.