Test your Knowledge on LPV in our quiz!

Do you know that lung protective strategies may have substantial benefits like less morbidity and mortality as well as decreased costs?

Take our 10-part quiz and find out!

Many anesthetists view lung protective ventilation (LPV) as the current standard of care for mechanical ventilation. Which of the following tidal volumes are normally used with LPV?

a. Mechanical ventilation with low tidal volumes (< 7-8 ml/kg predicted body weight)
b. Mechanical ventilation with high tidal volumes (≥10ml/kg predicted body weight)
c. Ventilating the patient while the anesthetist wears a cozy knitted protective lung vest

Correct answer:

LPV commonly uses low tidal volume ventilation of 4 to 8ml/kg. The rationale behind this approach is that low tidal volume ventilation has been shown to reduce ventilator-associated lung injury (VALI, also known as ventilator-induced lung injury or VILI) (Lipes J et al, Crit Care Res pract 2012;2012:416862; Salman D et al, Burns 2013;39:200-211).

Ventilator-associated (or induced) lung injury (VALI/VILI) is an acute lung injury that can develop during mechanical ventilation and may lead to a variety of complications. Adopting LPV can help because this approach.

a. Reduces volutrauma
b. Reduces barotrauma
c. Reduces biotrauma

Correct answer:

a, b and c.

LPV reduces volutrauma (hyperinflation and shearing injury), barotrauma (alveolar rupture and pneumothorax) as well as biotrauma (release of inflammatory mediators) (Beitler JR et al, Clin Chest Med 2016;37:633-646).

Historically, the recommendation regarding mechanical ventilation was to use larger-than-normal tidal volumes in order to secure adequate ventilation of the anesthetized patient. The use of positive end-expiratory pressure (PEEP) has been widespread since 1967, when it was reported that PEEP improved oxygenation. Which of the following best describe the principles of LPV?

a. LPV uses adequate positive end-expiratory pressure (PEEP) to prevent atelectasis
b. LPV limits tidal volume to avoid over-distending the lung
c. LPV uses high PEEP and high tidal volumes to allow for maximum ventilation

Correct answer:

a, b.

Lung-protective ventilation refers to a strategy in which positive end-expiratory pressure (PEEP) is used to prevent atelectasis, and tidal volume is limited to avoid over-distention of the lung.

LPV was first investigated in patients with acute respiratory distress syndrome (ARDS), a major cause of morbidity and mortality in Intensive Care Units (ICUs). ARDS patients were traditionally ventilated with tidal volumes of 10-15ml/kg, but a pivotal study on ARDS patients who received LPV showed.

a. A higher mortality in the LPV group
b. A lower mortality in the LPV group
c. A higher number of days without ventilator use in the LPV group

Correct answer:

b, c.

The study showed a lower mortality (31 vs. 39,8%) and 12 days vs. 10 without ventilator use (ARDS Network, NEJM 2000; 342:1301-1308).

There is also evidence regarding the effects of LPV in non-ARDS patients. In this setting, studies showed which main results?

a. Patients receiving lower tidal volumes had a decreased risk of lung injury and decreased mortality
b. Patients had an increased risk of extrapulmonary complications
c. Patients had a reduced risk of pulmonary and extrapulmonary complications.

Correct answer

a, c.

A metaanalysis and a study in the NEJM showed a decreased risk of lung injury development and mortality and a decreased risk of major pulmonary and extrapulmonary complications, respectively (Serpa Neto et al, JAMA 2012;308:1651-1659; IMPROVE Study, NEJM 2013;369:428-437).

LPV has been investigated in patients undergoing surgery regarding the incidence of pulmonary infections. What did the results show?

a. LPV patients had a higher incidence of pulmonary infections
b. LPV patients had a lower incidence of pulmonary infections
c. LPV patients had no pulmonary infections.

Correct answer:

A metaanalysis of 19 trials including 1,348 adult patients undergoing surgery showed that patients ventilated with LPV had a decreased risk of pulmonary infections (risk ratio 0.46) (Gu WJ et al, CMAJ 2015;187:E101-109).

Apart from LPV, other strategies have been suggested to reduce pulmonary complications after surgery. Which of the following have been investigated in this regard?

a. Smoking cessation
b. Lung recruitment maneuvers
c. Spontaneous breathing

Correct answer:

a, b, c.

All these strategies have been investigated in the effort to reduce postoperative pulmonary complications. Smoking cessation has not been found to have an effect, while lung recruitment maneuvers demonstrably reduced these complications in certain patients (Costa Leme A et a, JAMA 2017;317:1422-1432); spontaneous breathing has also been suggested to have positive effects (Neumann P et al, Crit Care Med 2005;33:1090-1095)

In which other patient groups apart from ARDS patients is LPV currently being used?

a. Obese patients
b. Pediatric patients
c. All patients

Correct answer:

a, b and c.

Existing literature recommends the use of protective ventilation with low tidal volumes in obese patients (Fernandez-Bustamente A et al, BMC Anesthesiology 2015;15:56). LPV has been cited as “safe to use” in children (Scohy T V et al, EACTA 2012, Abstract 84) and has therefore also been adopted in pediatric ventilation: a survey of 54 anesthesiologists from 47 centers in eleven countries found that a high proportion of respondents (88-96%) use lung-protective ventilation with a low tidal volume of 5-8ml/kg (Santschi M et al, Pediatr Crit Care Med 2013;14:e332-7).

LPV improves outcomes for patients. However, the costs associated with using this approach have also been investigated. What have the results of these studies shown?

a. The application of LPV is cost-effective
b. The application of LPV results in increase in quality-adjusted life-years
c. The application of LPV invariably leads to hospital bankruptcy.

Correct answer:

a, b.

One study investigating the cost-effectiveness of LPV in patients with acute lung injury found cost-effectiveness ratios for LPV of 22,000US$ per life saved and an increase in QALZs gained by 4.83 years (Cooke CR et al, Chest 2009;135:79-88).

LPV is mainly used in the Intensive Care Unit (ICU), less so in the operating room (OR). What is the best way to spread the method?

a. Talk about LPV on the phone
b. The evidence is available in a multitude of clinical papers and should be spread on congresses, meetings and symposia, for instance using informative videos.
c. Education of anesthetists.

Correct answer

b and c.

Studies have shown that many anesthesiologists still use the default settings of ventilation, therefore still use high tidal volumes (Hemmes SN et al, Eur J Anaesthesiol 2013;30:205-207), so education here is key: Searching databases such as PubMed will throw up a multitude of papers on the topic of LPV, and physicians should spread the message using meetings, congresses and symposia in anesthesiology and intensive care.

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