Acute Lung Injury Patients’ Survival and Recovery

Introduction

Even though clinicians spend much time to cope with such problems and conditions as adult respiratory distress syndrome and acute lung injury in the most efficient manner, there are still high rates of deaths that are caused by using ineffective therapies to improve ventilation in lungs (Gattinoni, Pesenti, & Carlesso, 2013; Guérin, 2014). Thus, patients with adult respiratory distress syndrome and acute lung injury usually suffer from decreases in respiratory functions, changes in the lung volume, and possible hypoxemia (Gattinoni et al., 2013; Venkategowda, Rao, Harde, Raut, & Mutkule, 2016).

The problem associated with providing care services to patients who have the determining conditions is in the necessity of decreasing the rate of deaths and increasing patients’ chances of survival with the help of the most effective therapies. The problem exists because there is no agreement regarding the use of prone and spine positions to improve oxygenation in patients with adult respiratory distress syndrome and acute lung injury. On the one hand, prone positioning is viewed as an effective alternative and as the most appropriate method in contrast to spine positioning because of positive impacts on the lung volume and ventilation that are proved concerning the research (Gattinoni et al., 2013). On the other hand, spine positioning is still used in many facilities because a lot of literature provides support for both approaches without stating that spine positioning is less effective than prone positioning (Guérin, 2014).

Trauma and surgical patients who suffer from adult respiratory distress syndrome and acute lung injury can be viewed as most affected by this problem because the selection of this or that position to improve oxygenation can influence their chances of survival and possible recovery directly. Adult respiratory distress syndrome and acute lung injury are the most severe forms of conditions and diseases that are related to the respiratory system (Gattinoni et al., 2013; Guérin, 2014).

Therefore, if clinicians have no evidence that this or that approach is most effective, the chances of patients with the described conditions to recover can decrease, and the selection of the less effective procedure can potentially lead to a patient’s death. Currently, both approaches to positioning are used in healthcare facilities depending on the guidelines that are followed in the concrete organization. However, in the majority of facilities, prone positioning is viewed as most beneficial to patients. Still, researchers pay attention to the fact that organizations can choose to refer to the prone position without supporting their choice by the evidence because patient outcomes are not studied enough, and more research is required (Gattinoni et al., 2013; Guérin, 2014). From this point, to focus on the effective intervention to address adult respiratory distress syndrome and acute lung injury in trauma and surgical patients and increase their chances of survival, it is necessary to compare the use of prone and spine positions and to focus on their outcomes for patients.

PICOT Question and Explanation

To conduct the study related to the comparison of prone and spine positions, as well as their effects on patients, it is necessary to formulate the PICO(T) question. Even though researchers and practitioners pay much attention to studying differences in using prone and supine positions while working with patients who suffer from adult respiratory distress syndrome or acute lung injury, there is still little evidence regarding the role of these positions in working with trauma or surgical patients (Venkategowda et al., 2016). Furthermore, some authors refer to ideas that the prone position usually has no obvious positive effects on patients who experience problems with breathing (Guérin, 2014; Venkategowda et al., 2016). Currently, researchers are concentrated on examining how the use of the prone position can stimulate patients’ recovery, but the focus is mainly on the general effects of this practice on a patient’s state (Gattinoni et al., 2013). The more detailed discussion of the problem is necessary to contribute to the selection of the best practices that can be used while supporting patients with adult respiratory distress syndrome and acute lung injury.

PICOT Question

The following PICO(T) question should be formulated for the study: For trauma or surgical patients who have adult respiratory distress syndrome and acute lung injury, does the prone position increase chances of survival and recovery compared with the supine position?

The PICOT Components

Population or Problem (P)

Trauma or surgical patients with such problems as adult respiratory distress syndrome or acute lung injury are selected as the target audience for the research. The reason is that these patients usually need additional ventilation and the application of specific therapies to address their conditions and relieve sufferings with the help of proposing certain procedures and changing prone or supine positions.

Intervention (I)

In this research, the focus is on studying the effects of using a prone position in therapies and procedures involving patients with adult respiratory distress syndrome or acute lung injury. Thus, the proposed intervention that should be analyzed in detail is the use of prone positioning while working with patients who have adult respiratory distress syndrome or acute lung injury. The prone position is observed when a patient lies on a bed with his or her face down (Guérin, 2014). In a clinical setting, the prone position can be used to improve patients’ respiratory abilities and facilitate oxygenation.

Comparison (C)

The prone position should be compared to the supine position to conclude about the impact on a patient’s state. The supine position can be observed when a patient lies flat on his or her back (Gattinoni et al., 2013; Guérin, 2014). Even though many clinicians report the decreased inflation in patients with respiratory problems when spine positioning is used, this approach is still proposed in many healthcare facilities as a part of the therapy (Gattinoni et al., 2013).

The outcome of Interest (O)

For the discussed research, the implementation of the proposed intervention is expected to lead to increased chances of survival and recovery for patients with adult respiratory distress syndrome and acute lung injury. The level of oxygenation can rise when patients lie in a prone position, and the ventilation therapy is proposed according to the guidelines for the procedure (Gattinoni et al., 2013; Guérin, 2014).

Time (T)

For this research, the focus on a certain period is not appropriate. Therefore, time is not mentioned in the formulated research question.

PICOT Articles and Search Words

Gattinoni, L., Pesenti, A., & Carlesso, E. (2013). Body position changes redistribute lung computed-tomographic density in patients with acute respiratory failure: Impact and clinical fallout through the following 20 years. Intensive Care Medicine, 39(11), 1909-1915.

In patients with acute respiratory distress syndrome (ARDS), in the supine position, there is a decrease of inflation along the sternum vertebral axis, up to lung collapse. In 1991 we published a report showing that, in ARDS patients, shifting from supine to prone position led immediately to the inversion of the inflation gradient and redistribution of densities from dorsal to ventral lung regions. This led to a “sponge model” as a wet sponge, similar to a heavy edematous lung, squeezes out the gas in the most dependent regions, due to the weight-related increase of the compressive forces. The sponge model accounts for density distribution in the prone position, for which the unloaded dorsal regions are recruited, while the loaded ventral region, collapses. Also, the sponge model accounts for the mechanism through which the positive end-expiratory pressure acts as a counterforce to oppose the collapsing, compressing forces.

The final result of pruning was that the inversion of gravitational forces, together with other factors such as lung-chest wall shape-matching and the heart weight led to a more homogeneous distribution of inflation throughout the lung parenchyma. This is associated with oxygenation improvement as the dorsal recruitment, for anatomical reasons prevails on the ventral de-recruitment. The more homogeneous distribution of inflation (i.e. of stress and strain) decreases/prevents the ventilator-induced lung injury, as consistently shown in animal experiments. Finally, and a series of clinical trials led to the conclusion that in patients with severe ARDS, the prone position provides a significant survival advantage.

Guérin, C. (2014). Prone ventilation in acute respiratory distress syndrome. European Respiratory Review, 23(132), 249-257.

Prone positioning has been used for many years in patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), with no clear benefit for patient outcome. Meta-analyses have suggested better survival in patients with an arterial oxygen tension (PaO2)/inspiratory oxygen fraction (FIO2) ratio <100 mmHg. A recent randomized controlled trial was performed in ARDS patients after a 12–24 h stabilization period and severity criteria (PaO2/FIO2 <150 mmHg at a positive end-expiratory pressure ≥5 cmH2O). This trial has demonstrated a significant reduction in mortality from 32.8% in the supine group to 16% in the prone group (p<0.001). The reasons for this dramatic effect are not clear but probably involves a reduction in ventilator-induced lung injury due to prone positioning, for which there is ample evidence in experimental and clinical studies.

This article aims to discuss: the rationale of prone positioning in patients with ALI/ARDS; the evidence of its use based on trial analysis; and the limitations of its use as well as the current place of prone positioning in the management of patients with ALI/ARDS.

From the currently available data, prone positioning should be used as first-line therapy in patients with severe ALI/ARDS.

Venkategowda, P. M., Rao, S. M., Harde, Y. R., Raut, M. K., & Mutkule, D. P. (2016). Prone position and pressure control inverse ratio ventilation in H1N1 patients with severe acute respiratory distress syndrome. Indian Journal of Critical Care Medicine, 20(1), 44-51.

Aim: To observe the 28 and 90 days mortality associated with the prone position and assist control-pressure control (with inverse ratio) ventilation (ACPC-IRV).

Materials and Methods: All patients who were admitted to our medical Intensive Care Unit (ICU) who are positive for H1N1 viral infection with severe acute respiratory distress syndrome (ARDS) and requiring invasive mechanical ventilation in prone position were included in our prospective observational study. Six patients who are positive for H1N1 required invasive ventilation in the prone position. These patients were planned to ventilate in prone for 16 h and in supine for 8 h daily until P/F ratio >150 with FiO2 of 0.6 or less and positive end-expiratory pressure <10 cm of H2O.

Results: At admission, among these six patients the mean tidal volume generated was about 376.6 ml which was in the range of 6-8 ml/kg predicted body weight. The mean lung injury score was 3.79, mean PaO2 /FiO2 ratio was 52.66, and the mean oxygenation index was 29.83. The mean duration of ventilation was 9.4 days (225.6 h). The ICU length of stay was 11.16 days. There was no mortality at 28 and 90 days.

Conclusion: Early prone combined with ACPC-IRV in H1N1 patients having severe ARDS can be used as rescue therapy and it should be confirmed by large observational studies.