Nasal/orotracheal tube switch to reduce length of mechanical ventilation in neurocritical patients: A propensity score matched analysis.

INTRODUCTION AND OBJECTIVES: Nasotracheal intubation was advocated to increase patients comfort and tube tolerance, but no study showed a clear benefit of nasotracheal intubation over orotracheal intubation. Neurocritically ill patients are a fragile group with specific requirements regarding ventilation and sedation. The aim of this study was to evaluate whether nasotracheal intubation might reduce length of mechanical ventilation in neurocritically ill patients. MATERIALS AND METHODS: We conducted a retrospective cohort study with propensity matched analysis including all patients who underwent prolonged mechanical ventilation in the neurocritical Intensive Care Unit. RESULTS: A total of 4030 patients were admitted during the period of interest and 312 entered the final analysis. Propensity score analysis identified 74 matched couples. Length of mechanical ventilation in patients who underwent early nasotracheal intubation resulted to be statistically significantly shorter than patients who underwent orotracheal intubation. Accordingly, length of sedation was significantly lower in patients with nasotracheal intubation, while no difference in complications occurred with similar length of stay. CONCLUSIONS: In critical care units using nasotracheal intubation in the standard management of patients, the nasotracheal route was associated with lesser need for sedatives leading to shorter mechanical ventilation in neurocritical patients. However, causality has to be proven by future randomized controlled trials.

Sustitución del tubo nasal/orotraqueal para reducir la duración de la ventilación mecánica en pacientes neurocríticos: análisis de emparejamiento por puntuación de propensión / Nasal/orotracheal tube switch to reduce length of mechanical ventilation in neurocritical patients: A propensity score matched analysis

Introducción y objetivos: Se ha aducido que la intubación nasotraqueal incrementa la comodidad y la tolerancia al tubo por parte del paciente, aunque ningún estudio ha demostrado un beneficio claro de la intubación nasotraqueal con respecto a la intubación orotraqueal. Los pacientes neurocríticos constituyen un grupo frágil con necesidades específicas, en cuanto a ventilación y sedación. El objetivo de este estudio fue evaluar si la intubación nasotraqueal podría reducir la duración de la ventilación mecánica en los pacientes neurocríticos. Materiales y métodos: Realizamos un estudio prospectivo de cohorte con análisis pareado de propensión, incluyendo a todos los pacientes que recibieron ventilación mecánica en la Unidad de Cuidados Intensivos neurocríticos. Resultados: Se ingresó a un total de 4.030 pacientes durante el periodo de interés, incluyendo a 312 de ellos en el análisis final. El análisis de la puntuación de propensión identificó a 74 parejas pareadas. La duración de la ventilación mecánica de los pacientes que recibieron intubación nasotraqueal temprana resultó ser significativamente inferior a la de los pacientes que recibieron intubación orotraqueal. Por tanto, la duración de la sedación fue considerablemente inferior en los pacientes con intubación nasotraqueal y no existió diferencia en cuanto a las complicaciones que se producen con las estancias de duración similar. Conclusiones: En las unidades de cuidados críticos que utiliza intubación nasotraqueal en el manejo estándar de los pacientes, la vía nasotraqueal estuvo asociada a una menor necesidad de sedantes, lo cual conllevó una ventilación mecánica más breve en los pacientes neurocríticos. Sin embargo, los ensayos controlados aleatorizados deberán probar la causalidad.(AU)

Introduction and objectives: Nasotracheal intubation was advocated to increase patients comfort and tube tolerance, but no study showed a clear benefit of nasotracheal intubation over orotracheal intubation. Neurocritically ill patients are a fragile group with specific requirements regarding ventilation and sedation. The aim of this study was to evaluate whether nasotracheal intubation might reduce length of mechanical ventilation in neurocritically ill patients. Materials and methods: We conducted a retrospective cohort study with propensity matched analysis including all patients who underwent prolonged mechanical ventilation in the neurocritical Intensive Care Unit. Results: A total of 4030 patients were admitted during the period of interest and 312 entered the final analysis. Propensity score analysis identified 74 matched couples. Length of mechanical ventilation in patients who underwent early nasotracheal intubation resulted to be statistically significantly shorter than patients who underwent orotracheal intubation. Accordingly, length of sedation was significantly lower in patients with nasotracheal intubation, while no difference in complications occurred with similar length of stay. Conclusions: In critical care units using nasotracheal intubation in the standard management of patients, the nasotracheal route was associated with lesser need for sedatives leading to shorter mechanical ventilation in neurocritical patients. However, causality has to be proven by future randomized controlled trials.(AU)

Impact on grafted kidney function of rocuronium-sugammadex vs cisatracurium-neostigmine strategy for neuromuscular block management. An Italian single-center, 2014-2017 retrospective cohort case-control study.

BACKGROUND: The impact of sugammadex in patients with end-stage renal disease undergoing kidney transplantation is still far from being defined. The aim of the study is to compare sugammadex to neostigmine for reversal of rocuronium- and cisatracurium-induced neuromuscular block (NMB), respectively, in patients undergoing kidney transplantation. METHODS: A single-center, 2014-2017 retrospective cohort case-control study was performed. A total of 350 patients undergoing kidney transplantation, equally divided between a sugammadex group (175 patients) and a neostigmine group (175 patients), were considered. Postoperative kidney function, evaluated by monitoring of serum creatinine and urea and estimated glomerular filtration rate (eGFR), was the endpoint. Other endpoints were anesthetic and surgical times, post-anesthesia care unit length of stay, postoperative intensive care unit admission, and recurrent NMB or complications. RESULTS: No significant differences in patient or, with the exception of drugs involved in NMB management, anesthetic, and surgical characteristics, were observed between the two groups. Serum creatinine (median [interquartile range]: 596.0 [478.0-749.0] vs 639.0 [527.7-870.0] µmol/L, p = 0.0128) and serum urea (14.9 [10.8-21.6] vs 17.1 [13.1-22.0] mmol/L, p = 0.0486) were lower, while eGFR (8.0 [6.0-11.0] vs 8.0 [6.0-10.0], p = 0.0473) was higher in the sugammadex group than in the neostigmine group after surgery. The sugammadex group showed significantly lower incidence of postoperative severe hypoxemia (0.6% vs 6.3%, p = 0.006), shorter PACU stay (70 [60-90] min vs 90 [60-105] min, p < 0.001), and reduced ICU admissions (0.6% vs 8.0%, p = 0.001). CONCLUSIONS: Compared to cisatracurium-neostigmine, the rocuronium-sugammadex strategy for reversal of NMB showed a better recovery profile in patients undergoing kidney transplantation.

Predictors of intubation in COVID-19 patients treated with out-of-ICU continuous positive airway pressure.

BACKGROUND: As delayed intubation may worsen the outcome of coronavirus disease 2019 (COVID-19) patients treated with continuous positive airway pressure (CPAP), we sought to determine COVID-specific early predictors of CPAP failure. METHODS: In this observational retrospective multicentre study, we included all COVID-19 patients treated with out-of-ICU CPAP, candidates for intubation in case of CPAP failure. From these patients, we collected demographic and clinical data. RESULTS: A total of 397 COVID-19 patients were treated with CPAP for respiratory failure, with the therapeutic goal of providing intubation in case of CPAP failure. Univariable analysis showed that, age, lactate dehydrogenase (LDH) and white cell counts were all significantly lower in patients with successful CPAP treatment compared to those failing it and undergoing subsequent intubation. The percentage changes between baseline and CPAP application in the ratio of partial pressure arterial oxygen (PaO2) and fraction of inspired oxygen (FiO2), PaO2, respiratory rate and ROX index were higher in patients experiencing successful CPAP compared to those failing it. FiO2 and male gender were also significantly associated with intubation. Multivariable analysis adjusting for age, gender, Charlson comorbidity index, percentage change in PaO2/FiO2 or PaO2 and FiO2 separately, lactate, white blood cell count, LDH and C-reactive protein levels led to an area under the curve of 0.818 and confirmed that age, LDH and percentage increase in PaO2/FiO2 are predictors of intubation. CONCLUSIONS: In COVID-19 patients requiring CPAP, age, LDH and percentage change in PaO2/FiO2 after starting CPAP are predictors of intubation.

High-flow nasal oxygen therapy in intensive care and anaesthesia.

Oxygen therapy is first-line treatment for hypoxaemic acute respiratory failure (ARF). High-flow nasal oxygen therapy (HFNO) represents an alternative to conventional oxygen therapy. HFNO provides humidified, titrated oxygen therapy matching or even exceeding the patients' inspiratory demand. The application of HFNO is becoming widespread in Intensive Care Units (ICUs), favoured by increasing evidence based on numerous studies supporting its efficacy. The mechanisms of action and physiological effects of HFNO are not yet fully understood. Pharyngeal dead space washout, decrease in airway resistance, generation of a positive end-expiratory pressure, and enhanced delivery of oxygen are all alleged to be potential mechanisms. The emerging evidence suggests that HFNO is effective in improving oxygenation in most patients with hypoxaemic ARF of different aetiologies. Notwithstanding the potential benefit of HFNO in the management of hypoxaemia, further large cohort studies are necessary to clarify the indications, contraindications and factors associated with HFNO failure. HFNO may also be valuable in reducing the need for tracheal intubation in the management of post-extubation ARF. In addition, HFNO has been proposed to limit oxygen desaturation by prolonging apnoeic oxygenation during intubation both in ICUs and operating theatres.

Ten important articles on noninvasive ventilation in critically ill patients and insights for the future: A report of expert opinions.

BACKGROUND: Noninvasive ventilation is used worldwide in many settings. Its effectiveness has been proven for common clinical conditions in critical care such as cardiogenic pulmonary edema and chronic obstructive pulmonary disease exacerbations. Since the first pioneering studies of noninvasive ventilation in critical care in the late 1980s, thousands of studies and articles have been published on this topic. Interestingly, some aspects remain controversial (e.g. its use in de-novo hypoxemic respiratory failure, role of sedation, self-induced lung injury). Moreover, the role of NIV has recently been questioned and reconsidered in light of the recent reports of new techniques such as high-flow oxygen nasal therapy. METHODS: We conducted a survey among leading experts on NIV aiming to 1) identify a selection of 10 important articles on NIV in the critical care setting 2) summarize the reasons for the selection of each study 3) offer insights on the future for both clinical application and research on NIV. RESULTS: The experts selected articles over a span of 26 years, more clustered in the last 15 years. The most voted article studied the role of NIV in acute exacerbation chronic pulmonary disease. Concerning the future of clinical applications for and research on NIV, most of the experts forecast the development of innovative new interfaces more adaptable to patients characteristics, the need for good well-designed large randomized controlled trials of NIV in acute "de novo" hypoxemic respiratory failure (including its comparison with high-flow oxygen nasal therapy) and the development of software-based NIV settings to enhance patient-ventilator synchrony. CONCLUSIONS: The selection made by the experts suggests that some applications of NIV in critical care are supported by solid data (e.g. COPD exacerbation) while others are still waiting for confirmation. Moreover, the identified insights for the future would lead to improved clinical effectiveness, new comparisons and evaluation of its role in still "lack of full evidence" clinical settings.

Surviving sepsis campaign: international guidelines for management of sepsis and septic shock: 2016

OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy wasdeveloped at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroupsand among the entire committee served as an integral part of the development. METHODS: The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. CONCLUSIONS: Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.(AU)

Intravenous infusion of magnesium sulfate and postoperative analgesia in total knee arthroplasty.

BACKGROUND: The effectiveness of combining magnesium (Mg) administration with both general and spinal anesthesia to reduce postoperative pain and analgesic consumption is still debated. We evaluated the effects of an intravenous (IV) infusion of Mg sulphate on analgesic consumption and postoperative pain score after total knee arthroplasty performed under spinal anesthesia. METHODS: We studied 40 patients who underwent spinal anesthesia with bupivacaine plus morphine. Patients were randomly assigned to two groups, each of 20 patients, who received either treatment (i.e., intravenous Mg sulphate 40 mg kg(-1) followed by an infusion of 10 mg kg(-1) h(-1)), or the same amounts of isotonic saline (controls). Irrespective of the group of randomization, all patients received postoperative paracetamol, ketorolac, and patient-controlled analgesia with morphine. RESULTS: The Mg postoperative blood level was 0.85 ± 0.02 mmol/L and 1.25 ± 0.11 mmol/L for C and Mg groups, respectively (P<0.001). Sensory level of the spinal block, height of spinal block, mean time to first pain and incidence of PONV were similar in the two groups. Morphine consumption did not show any statistically significant difference between the two groups. The pain score was not significantly different between the two groups. No severe adverse effects were recorded after Mg infusion. CONCLUSION: IV perioperative administration of Mg did not influence postoperative pain control and analgesic consumption after total knee arthroplasty. More studies should be performed with different intra and postoperative pain protocols to enhance the potential anti-nociceptive effect of Mg.

Osteopontin induces soluble urokinase-type plasminogen activator receptor production and release.

BACKGROUND: Osteopontin (OPN) and soluble urokinase plasminogen activator receptor (suPAR) have been proposed as markers of disease severity and risk-stratification in infection and inflammation. In breast cancer, OPN and the membrane bound form of urokinase plasminogen activator receptor (uPAR) are functionally related, as OPN-induced cell migration depends on uPAR triggering by urokinase plasminogen activator (uPA). The aim of this study was to prospectively evaluate the kinetic of OPN and suPAR blood levels in patients developing septic shock (SS) compared to those not developing SS, and to investigate the relationships between these two biomarkers in immune cells in vitro. METHODS: We measured the levels of OPN and suPAR for 15 days in forty-three patients, defined a priory as at risk to develop septic shock. Moreover, we investigated in vitro the effect of recombinant OPN on uPAR and suPAR expression in monocytes. RESULTS: We found that OPN and suPAR levels were directly correlated to each other both at intensive care unit admission and on the day patients met SIRS/sepsis or septic shock criteria. In patients developing septic shock, OPN increased prior to suPAR and was already detectable up to 4 days before the shock development. In vitro, OPN induced suPAR production in monocytes by increasing both uPAR gene expression, and suPAR release from the cell surface. CONCLUSION: These data suggest that OPN is partly responsible for the increased plasma levels of suPAR and might be a valuable tool to predict the occurrence of septic shock.

Prolonged weaning: from the intensive care unit to home.

Weaning is the process of withdrawing mechanical ventilation which starts with the first spontaneous breathing trial (SBT). Based on the degree of difficulty and duration, weaning is classified as simple, difficult and prolonged. Prolonged weaning, which includes patients who fail 3 SBTs or are still on mechanical ventilation 7 days after the first SBT, affects a relatively small fraction of mechanically ventilated ICU patients but these, however, requires disproportionate resources. There are several potential causes which can lead to prolonged weaning. It is nonetheless important to understand the problem from the point of view of each individual patient in order to adopt appropriate treatment and define precise prognosis. An otherwise stable patient who remains on mechanical ventilation will be considered for transfer to a specialized weaning unit (SWU). Though there is not a precise definition, SWU can be considered as highly specialized and protected environments for patients requiring mechanical ventilation despite resolution of the acute disorder. Proper staffing, well defined short-term and long-term goals, attention to psychological and social problems represent key determinants of SWU success. Some patients cannot be weaned, either partly or entirely, and may require long-term home mechanical ventilation. In these cases the logistics relating to caregivers and the equipment must be carefully considered and addressed.

Bench comparative evaluation of a new generation and standard helmet for delivering non-invasive ventilation.

OBJECTIVE: To evaluate the performance of a new helmet (NH) recently introduced into clinical use relative to that of the standard helmet (SH) in terms of delivering non-invasive continuous positive airway pressure (nCPAP) and pressure support ventilation (nPSV). DESIGN: This was a bench study using a mannequin connected to an active lung simulator. The SH was fastened to the mannequin by armpit braces, which are not needed to secure the NH. MEASUREMENTS: The inspiratory and expiratory variations in nCPAP delivered with two different simulated efforts (Pmus), were determined relative to the preset CPAP level. nPSV was applied at two simulated respiratory rates (RR) and two cycling-off flow thresholds. We measured inspiratory trigger delay (Delay trinsp), expiratory trigger delay (Delay trexp), time of synchrony (Time sync), trigger pressure drop (ΔP trigger), airway pressure-time product during the triggering phase (PTPt), the initial 200 ms from the onset of the ventilator pressurization (PTP 200), and the initial 300 and 500 ms from the onset of the simulated effort; this two latter parameters were expressed as the percentage of the area of ideal pressurization (PTP 300-index and PTP 500-index, respectively). RESULTS: In nCPAP, at both Pmus, the differences between the two interfaces at both Pmus were small and clinically irrelevant. In nPSV, regardless of the setting, NH resulted in significantly smaller trigger delays, ΔP trigger, and PTPt. Time sync, PTP 200, PTP 300-index, and PTP 500-index were also significantly higher with the NH compared to the SH, irrespective of the setting. CONCLUSIONS: Compared to the SH, the NH is equally effective in delivering nCPAP and more effective in delivering nPSV, and it is used to avoid the need for armpit braces.

Effectiveness and predictors of success of noninvasive ventilation during H1N1 pandemics: a multicenter study.

BACKGROUND: The use of non-invasive ventilation (NIV) in acute hypoxemic respiratory failure (AHRF) due to H1N1 virus infection is controversial. In this multicenter study we aimed to assess the efficacy of NIV in avoiding endotracheal intubation (ETI) and to identify predictors of success or failure. METHODS: In this prospective multicenter study, 98 patients with new pulmonary infiltrate(s) sustained by H1N1 virus and a PaO(2)/FiO2<300 were eligible for study; 38/98 required immediate ETI, while the others received NIV as a first line therapy; 13/60 patients failed NIV and were intubated after 5.8+5.5 hours from enrolment. The remaining 47/60 patients were successfully ventilated with NIV. RESULTS: Hospital mortality was significantly higher in those patients who failed NIV vs. those who succeeded (53.8% vs. 2.1%; OR=0.52, P<0.001). ETI was associated with higher number of infectious complications, mainly sepsis and septic shock. The OR of having one of these events in the NIV failure group vs. NIV success was 16.7, P<0.001. According to logistic regression model, a SAPS II>29 and a PaO(2)/FIO(2)≤127 at admission and PaO2/FIO(2)≤149 after 1 hr of NIV were independently associated with the need for ETI. CONCLUSION: The early application of NIV, with the aim to avoid invasive ventilation, during the H1N1 pandemics was associated with an overall success rate of 47/98 (48%). Patients presenting at admission with an high SAPS II score and a low PaO(2)/FiO(2) ratio and/or unable to promptly correct gas exchange are at high risk of intubation and mortality.

What the pulmonary specialist should know about the new inhalation therapies.

A collaboration of multidisciplinary experts on the delivery of pharmaceutical aerosols was facilitated by the European Respiratory Society (ERS) and the International Society for Aerosols in Medicine (ISAM), in order to draw up a consensus statement with clear, up-to-date recommendations that enable the pulmonary physician to choose the type of aerosol delivery device that is most suitable for their patient. The focus of the consensus statement is the patient-use aspect of the aerosol delivery devices that are currently available. The subject was divided into different topics, which were in turn assigned to at least two experts. The authors searched the literature according to their own strategies, with no central literature review being performed. To achieve consensus, draft reports and recommendations were reviewed and voted on by the entire panel. Specific recommendations for use of the devices can be found throughout the statement. Healthcare providers should ensure that their patients can and will use these devices correctly. This requires that the clinician: is aware of the devices that are currently available to deliver the prescribed drugs; knows the various techniques that are appropriate for each device; is able to evaluate the patient's inhalation technique to be sure they are using the devices properly; and ensures that the inhalation method is appropriate for each patient.

Influence of ventilator settings on patient-ventilator synchrony during pressure support ventilation with different interfaces.

OBJECTIVE: To evaluate patient-ventilator interaction during pressure support ventilation (PSV) delivered with three interfaces [endotracheal tube (ET), face mask (FM), and helmet (H)] at different pressurization times (Time(press)), cycling-off flow thresholds (Tr(exp)), and respiratory rates (RR) in a bench study, and with FM and H in a healthy volunteers study. DESIGN: Bench study using a mannequin connected to an active lung simulator, and human study including eight healthy volunteers. MEASUREMENTS: PSV was delivered through the three interfaces with three different RR in the bench study, and through FM and H at two different RR in the human study. The mechanical and the neural RR, Ti, Te, inspiratory trigger delay (Delay(trinsp)), pressurization time, and expiratory trigger delay were randomly evaluated at various ventilator settings (Time(press)/Tr(exp): 50%/25%, default setting; 20%/5%, slow setting; 80%/60%, fast setting). RESULTS: Bench study: patient-ventilator synchrony was significantly better with ET, with lower Delay(trinsp) and higher time of assistance (P < 0.001); the combination Time(press)/Tr(exp) 20%/5% at RR 30 produced the worst interaction, with higher rate of wasted efforts (WE) compared with Time(press)/Tr(exp) 80%/60% (20%, 40%, and 50% of WE versus 0%, 16%, and 26% of all spontaneous breaths, with ET, FM, and H, respectively; P < 0.01). In both studies, compared with H, FM resulted in better synchrony. CONCLUSION: Patient-ventilator synchrony was significantly better with ET during the bench study; in the human study, FM outperformed H.

NAVA ventilation.

Neurally adjusted ventilatory assist (NAVA) is a form of partial ventilatory support wherein the machine applies positive pressure to the airway opening throughout each inspiration. In contrast to all other modes of ventilation, which adopt conventional pneumatic signals (flow, volume, and airway pressure) to drive and control the ventilator operation, NAVA utilizes the electrical activity of the diaphragm, which is the best available signal to estimate the respiratory drive and to trigger on and cycle off the delivery of the mechanical assistance and regulate its amount and intra-breath profile. With NAVA, therefore, the patient retains full control of the breathing pattern. Following the first description of NAVA ten years ago, various studies have been performed on this mode of ventilation, either in animal models, healthy subjects, or in adult and pediatric critically ill patients. These investigations indicate that this novel mode is efficient in unloading the respiratory muscles and maintaining adequate gas exchange while improving the patient-ventilator interaction. This review article aims to summarize the results of the studies published to date on this topic.

Clonidine in perioperative medicine and intensive care unit: more than an anti-hypertensive drug.

Clonidine is classified as an imidazoline and it is the prototypical alpha-2 receptor agonists. It has been used for several years to treat hypertension. It has also been used, "off label", for a variety of purposes, including opioid and anesthetic sparing effects, anxiolysis and sedation, drug withdrawal as well as stabilizing blood pressure and reducing stress response to surgery. Particularly in the case of patients with overt or underlying cardiac disease and in those at risk of perioperative ischemia the action of clonidine can be expected to reduce the risk of procedure-related cardiac events. In addition, clonidine used as a premedication drug before surgery or surgical procedure, has been shown to substantially reduce anaesthetic, benzodiazepine and opioids requirements. However, its "off label" use, the absence of an intravenous form of in the United States, possible inadvertent hypotension, bradycardia or post-operative sedation, and the variability of the haemodynamic response to different doses or rates of administration, have limited its use in clinical practice. This review discusses the potential role of clonidine and the supporting evidence for the use of this drug beyond its anti-hypertensive use in perioperative medicine and critical care in adults patients.

Non-invasive ventilation.

Non-invasive ventilation (NIV) is an effective technique that can avert side effects and complications associated with endotracheal intubation. NIV is primarily used to avert the need for endotracheal intubation in patients with early stage acute respiratory failure (ARF), and to prevent postextubation respiratory failure in patients considered to be at risk. It can also be used as an alternative to invasive ventilation at a more advanced stage of ARF or to facilitate the process of weaning from mechanical ventilation. The success of NIV relies on several factors including the type and severity of ARF, the underlying disease, the timing, the location of treatment, and the experience of the team. In this review article, we analyze, compare, and discuss the results of studies in which NIV was applied in different pathologies and with different timing during the evolution of ARF.