REMI 1928E. Neuromuscular blocking agents in severe sepsis patients

[Versión en español]

      

Original Article: Steingrub JS, Lagu T, Rothberg MB, Nathanson BH, Raghunathan K, Lindenauer PK. Treatment with neuromuscular blocking agents and the risk of in-hospital mortality among mechanically ventilated patients with severe sepsis. Crit Care Med 2014; 42(1): 90-96. [Summary] [Related Articles]

          

Introduction: Recent studies have shown the potential benefit of using continuous muscle relaxation for 48 hours in the early stages of Acute Respiratory Distress Syndrome (ARDS) [1, 2].  This beneficial effect may occur because it facilitates the application of a protective ventilatory strategy and by decreasing ventilator-patient asynchrony during this period, but its routine use remains controversial [3]. In the present study the authors explore the relationship between treatment with neuromuscular blocking agents (NMBA) and prognosis in ventilated patients with severe sepsis, regardless of the existence of ARDS.

      

Abstract: The study analyzed a cohort of patients who required mechanical ventilation within 48 hours of hospital admission with the diagnosis of severe sepsis and explore by the method of "propensity score matching" the relationship of NMBA use on mortality. Patients were selected from a prospective database between 2004 and 2006 and including 7,864 patients, of whom 1,818 received NMBA. The main finding of this study is that the use of NMBA in this population was associated with a reduced risk of in-hospital mortality (risk ratio 0.88, 95% CI 0.80 to 0.96), absolute risk reduction 4.3% (95% CI -11.5% to -1.5%).

      

Comment: In a recent systematic review on the use of cisatracurium infusion in ARDS patients (three studies and 431 patients) a significant reduction in mortality was observed, although no effects on the total duration of mechanical ventilation or incidence of neuromuscular weakness were noted [4, 5]. However the number of ARDS patients studied is not very high and some controversy remains about its routine use [5]. To my knowledge, the present study is really confusing, with a very complex statistical design that looks more like a game than a mathematical interpretation of what happens in the clinical practice. To adequately interpret this study it must be taken into account: the initial database includes about 71,000 patients, but only 7,864 are analyzed, patients receiving NMBA were younger (62 and 68), and other potentially prognostic factors such as comorbidities are unknown. The database included patients receiving any muscle relaxant (atracurium, cisatracurium, doxacurium, mivacurium, pancuronium, rocuronium, or vecuronium), even receiving only one dose for 1 day, and not explains nothing of something as basic as the ventilation mode, or the indication of relaxation. It certainly is an interesting study, but its results need to be interpreted with great caution and could serve to generate hypotheses but  not to guide the treatment of patients.

     

Federico Gordo Vidal

Hospital Universitario del Henares, Coslada, Madrid.

© REMI, http://medicina-intensiva.com. Enero 2014.

      

Links:

1. Papazian L, Forel JM, Gacouin A, Penot-Ragon C, Perrin G, Loundou A, Jaber S, Arnal JM, Perez D, Seghboyan JM, Constantin JM, Courant P, Lefrant JY, Guérin C, Prat G, Morange S, Roch A. Neuromuscular Blockers in Early Acute Respiratory Distress Syndrome. N Engl J Med 2010; 363: 1107-1116. [PubMed]
2. Bloqueantes neuromusculares en la fase precoz del SDRA. Palencia Herrejón E. [REMI 2010; 10(9): 1554]
3. Bloqueo neuromuscular con cisatracurio en el SDRA precoz: no digas nunca jamás, pero siempre tampoco. Editorial. Gordo Vidal F, Garnero AJ. [REMI 2010; 10 (9): E69]
4. Neuromuscular blocking agents in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials. Alhazzani W, Alshahrani M, Jaeschke R, Forel JM, Papazian L, Sevransky J, Meade MO. Crit Care 2013, 17: R43. [PubMed]
5. Bloqueo neuromuscular en el SDRA: revisión sistemática. Molina Lobo R. [REMI 2013; 13(4): 1842]

Búsqueda en PubMed:

• Plain Language: Neuromuscular Blockers in ARDS
• Sintax: Neuromuscular Blockers AND Acute Respiratory Distress Syndrome
• [Results]

                

REMI 1927E. Noninvasive positive-pressure ventilation as a weaning strategy

[Versión en español]

Original article: Noninvasive positive-pressure ventilation as a weaning strategy for intubated adults with respiratory failure.Burns KE, Meade MO, Premji A, Adhikari NK. Cochrane Database Syst Rev 2013; 12: CD004127. [Abstract] [Related articles]
   
Introduction: Many complications related to the use of mechanical ventilation, in particular ventilator-associated pneumonia (VAP), are time dependent. Therefore, weaning should be started as early as possible and can occupy up to 40% of total mechanical ventilation time [1]. Substitution of traditional weaning with non-invasive mechanical ventilation (NIV) weaning can have a significant impact on the duration of invasive mechanical ventilation and thus may reduce the incidence of complications.
   
Abstract: The aim of this review is to compare weaning by means of early extubation followed by immediate application of NIV or continued IPPV weaning in adults with respiratory failure of any cause. The primary outcome was to determine whether NIV reduces mortality compared with invasive positive-pressure ventilation (IPPV) weaning. Secondary outcomes were the differences between the two strategies in terms of weaning failure, NAV incidence, ICU and hospital lenght of stay, total duration of mechanical ventilation and intubation. With this aim, randomized or quasi-randomized clinical trials comparing the two techniques were searched in the Cochrane Central Register of Controlled Trials, Medline and Embase, among other databases. 16 trials with 994 participants, most with Chronic Obstructive Pulmonary Disease (COPD) were identified. In them, mortality was significantly lower with NIV compared to traditional weaning (RR 0.53, 95% CI 0.36 to 0.80, P = 0.002). This benefit was significantly higher in the 9 trials enrolling only COPD patients (RR 0.36, 95% CI 0.24 to 0.56) than in those with mixed population (RR 0.81, 95% CI 0.47 to 1.40). NIV weaning also significantly reduced weaning failure and VAP, shortened ICU and hospital lenght of stay and total time in mechanical ventilation (mean difference -7.44 days, 95% CI -10.34 to -4.55). NIV weaning also reduced the rates of re-intubation and tracheostomy. NIV had no effect on the duration of mechanical ventilation related to weaning.
   
Comments: This review suggests that NIV may be an effective and safe technique of weaning (since it does not increase the failure rate of weaning or reintubation), at least in patients with COPD. However, it must be noted that for patients with IPPV weaning, different ventilatory modes were used in each trial, including SIMV or PSV, with gradual reduction in pressure support that may have delayed the decision to perform the T-tube test. Also, this test lasted for a variable period of time, from half an hour to three hours.
      

Ramón Díaz-Alersi

Hospital U. Puerto Real, Cádiz.

© REMI, http://medicina-intensiva.com. January 2014
   
Links:

1. A comparison of four methods of weaning patients from mechanical ventilation. Spanish Lung Failure Collaborative Group. Esteban A, Frutos F, Tobin MJ, Alía I, Solsona JF, Valverdú I, Fernández R, de la Cal MA, Benito S, Tomás R, et al. N Engl J Med 1995; 332: 345-350.[PubMed] [Full text] 

PubMed Search: 

• Plain Language: Noninvasive positive-pressure ventilation as weaning strategy
• Syntax: Noninvasive positive-pressure ventilation AND weaning strategy
• [Results]