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How to perform a recruitment maneuver

Artikel

Autor: Clinical Experts Group, Hamilton Medical

Datum: 30.09.2020

Last change: 30.09.2020

(Originally published 02.10.2017) White paper removed from downloads, P/V Tool user guide and quick reference card added.
A recruitment maneuver (RM) is a transient increase in transpulmonary pressure applied to reaerate the collapsed lung.
How to perform a recruitment maneuver

Sustained inflation method

​Several methods have been described for performing recruitment maneuvers, with the most commonly used being the sustained inflation method.

Contraindications for RMs are hemodynamic instability, COPD and lung emphysema, bronchopleural fistula, and acute cor pulmonale. Relative contraindications are increased intracranial pressure and pregnancy.

RM with the P/V Tool Pro

The P/V Tool® Pro on Hamilton Medical ventilators can be used to perform a sustained inflation RM. The clinician needs to set the following (see Figure 1 below):

  • Initial PEEP: Usually this equates to the current PEEP.
  • Top pressure (Ptop): In most cases, 40 cmH2O is used. Patients with a heavy chest wall may require a higher top pressure of up to 60 cmH2O (Borges JB, Okamoto VN, Matos GF, et al. Reversibility of lung collapse and hypoxemia in early acute respiratory distress syndrome. Am J Respir Crit Care Med. 2006;174(3):268-278. doi:10.1164/rccm.200506-976OC1​, Cressoni M, Chiumello D, Algieri I, et al. Opening pressures and atelectrauma in acute respiratory distress syndrome. Intensive Care Med. 2017;43(5):603-611. doi:10.1007/s00134-017-4754-82​).
  • End PEEP: PEEP after the recruitment maneuver. This setting is of major importance to keep the lung aerated.
  • Ramp speed: The setting can range from 2 to 5 cmH2O/s. A slower ramp may be tolerated better, but increases the total duration of the maneuver.
  • Time of the pause (Tpause): The optimal duration for application of the top pressure is 10 s (Arnal JM, Paquet J, Wysocki M, et al. Optimal duration of a sustained inflation recruitment maneuver in ARDS patients. Intensive Care Med. 2011;37(10):1588-1594. doi:10.1007/s00134-011-2323-03​).

Note that if esophageal pressure measurement is available, the top pressure can be titrated to target a transpulmonary pressure of 20 cmH2O during the RM (Baedorf Kassis E, Loring SH, Talmor D. Recruitment maneuvers: using transpulmonary pressure to help Goldilocks. Intensive Care Med. 2017;43(8):1162-1163. doi:10.1007/s00134-017-4784-24​).

Before starting and during the RM

Before starting the maneuver, the cuff of the endotracheal tube should be overinflated to prevent any air leakage during the maneuver. If using the integrated IntelliCuff pressure controller, this step will be performed automatically.

During the maneuver, the clinician should monitor the mean arterial pressure. A decrease in mean arterial pressure indicates a decrease in cardiac output due to high thoracic pressure. The RM can be stopped at any time in the case of severe hemodynamic compromise.

Assessing the maneuver's efficacy

The basis for assessing the efficacy of the RM is the increase in volume during the RM (see Figure 2 below). This volume increase can be measured using the cursor and represents the volume of lung that was reaerated during the RM, assuming there was no air leakage. A volume increase of more than 2 ml/kg predicted body weight (PBW) is considered significant. 

A successful RM followed by an appropriate PEEP setting is associated with an increase in static compliance, as well as an improvement in oxygenation and CO2 elimination. 

See the documents available for download below. These documents are also available in other languages from our Resource Center.

Screenshot showing settings for recruitment maneuver
Figure 1: Setting of a sustained inflation RM using the P/V Tool
Screenshot showing settings for recruitment maneuver
Figure 1: Setting of a sustained inflation RM using the P/V Tool
Screenshot showing loop and volume increase
Figure 2: The volume increase during the pause represents the volume of lung that was reaerated
Screenshot showing loop and volume increase
Figure 2: The volume increase during the pause represents the volume of lung that was reaerated

Reversibility of lung collapse and hypoxemia in early acute respiratory distress syndrome.

Borges JB, Okamoto VN, Matos GF, et al. Reversibility of lung collapse and hypoxemia in early acute respiratory distress syndrome. Am J Respir Crit Care Med. 2006;174(3):268-278. doi:10.1164/rccm.200506-976OC



RATIONALE

The hypothesis that lung collapse is detrimental during the acute respiratory distress syndrome is still debatable. One of the difficulties is the lack of an efficient maneuver to minimize it.

OBJECTIVES

To test if a bedside recruitment strategy, capable of reversing hypoxemia and collapse in > 95% of lung units, is clinically applicable in early acute respiratory distress syndrome.

METHODS

Prospective assessment of a stepwise maximum-recruitment strategy using multislice computed tomography and continuous blood-gas hemodynamic monitoring.

MEASUREMENTS AND MAIN RESULTS

Twenty-six patients received sequential increments in inspiratory airway pressures, in 5 cm H(2)O steps, until the detection of Pa(O(2)) + Pa(CO(2)) >or= 400 mm Hg. Whenever this primary target was not met, despite inspiratory pressures reaching 60 cm H(2)O, the maneuver was considered incomplete. If there was hemodynamic deterioration or barotrauma, the maneuver was to be interrupted. Late assessment of recruitment efficacy was performed by computed tomography (9 patients) or by online continuous monitoring in the intensive care unit (15 patients) up to 6 h. It was possible to open the lung and to keep the lung open in the majority (24/26) of patients, at the expense of transient hemodynamic effects and hypercapnia but without major clinical consequences. No barotrauma directly associated with the maneuver was detected. There was a strong and inverse relationship between arterial oxygenation and percentage of collapsed lung mass (R = - 0.91; p < 0.0001).

CONCLUSIONS

It is often possible to reverse hypoxemia and fully recruit the lung in early acute respiratory distress syndrome. Due to transient side effects, the required maneuver still awaits further evaluation before routine clinical application.

Opening pressures and atelectrauma in acute respiratory distress syndrome.

Cressoni M, Chiumello D, Algieri I, et al. Opening pressures and atelectrauma in acute respiratory distress syndrome. Intensive Care Med. 2017;43(5):603-611. doi:10.1007/s00134-017-4754-8



PURPOSE

Open lung strategy during ARDS aims to decrease the ventilator-induced lung injury by minimizing the atelectrauma and stress/strain maldistribution. We aim to assess how much of the lung is opened and kept open within the limits of mechanical ventilation considered safe (i.e., plateau pressure 30 cmH2O, PEEP 15 cmH2O).

METHODS

Prospective study from two university hospitals. Thirty-three ARDS patients (5 mild, 10 moderate, 9 severe without extracorporeal support, ECMO, and 9 severe with it) underwent two low-dose end-expiratory CT scans at PEEP 5 and 15 cmH2O and four end-inspiratory CT scans (from 19 to 40 cmH2O). Recruitment was defined as the fraction of lung tissue which regained inflation. The atelectrauma was estimated as the difference between the intratidal tissue collapse at 5 and 15 cmH2O PEEP. Lung ventilation inhomogeneities were estimated as the ratio of inflation between neighboring lung units.

RESULTS

The lung tissue which is opened between 30 and 45 cmH2O (i.e., always closed at plateau 30 cmH2O) was 10 ± 29, 54 ± 86, 162 ± 92, and 185 ± 134 g in mild, moderate, and severe ARDS without and with ECMO, respectively (p < 0.05 mild versus severe without or with ECMO). The intratidal collapses were similar at PEEP 5 and 15 cmH2O (63 ± 26 vs 39 ± 32 g in mild ARDS, p = 0.23; 92 ± 53 vs 78 ± 142 g in moderate ARDS, p = 0.76; 110 ± 91 vs 89 ± 93, p = 0.57 in severe ARDS without ECMO; 135 ± 100 vs 104 ± 80, p = 0.32 in severe ARDS with ECMO). Increasing the applied airway pressure up to 45 cmH2O decreased the lung inhomogeneity slightly (but significantly) in mild and moderate ARDS, but not in severe ARDS.

CONCLUSIONS

Data show that the prerequisites of the open lung strategy are not satisfied using PEEP up to 15 cmH2O and plateau pressure up to 30 cmH2O. For an effective open lung strategy, higher pressures are required. Therefore, risks of atelectrauma must be weighted versus risks of volutrauma.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT01670747 ( www.clinicaltrials.gov ).

Optimal duration of a sustained inflation recruitment maneuver in ARDS patients.

Arnal JM, Paquet J, Wysocki M, et al. Optimal duration of a sustained inflation recruitment maneuver in ARDS patients. Intensive Care Med. 2011;37(10):1588-1594. doi:10.1007/s00134-011-2323-0



PURPOSE

To measure the dynamics of recruitment and the hemodynamic status during a sustained inflation recruitment maneuver (RM) in order to determine the optimal duration of RM in acute respiratory distress syndrome (ARDS) patients.

METHODS

This prospective study was conducted in a 12-bed intensive care unit (ICU) in a general hospital. A 40 cmH(2)O sustained inflation RM maintained for 30 s was performed in 50 sedated ventilated patients within the first 24 h of meeting ARDS criteria. Invasive arterial pressures, heart rate, and SpO(2) were measured at 10-s intervals during the RM. The volume increase during the RM was measured by integration of the flow required to maintain the pressure at 40 cmH(2)O, which provides an estimation of the volume recruited during the RM. Raw data were corrected for gas consumption and fitted with an exponential curve in order to determine an individual time constant for the volume increase.

RESULTS

The average volume increase and time constant were 210 ± 198 mL and 2.3 ± 1.3 s, respectively. Heart rate, diastolic arterial pressure, and SpO(2) did not change during or after the RM. Systolic and mean arterial pressures were maintained at 10 s, decreased significantly at 20 and 30 s during the RM, and recovered to the pre-RM value 30 s after the end of the RM (ANOVA, p < 0.01).

CONCLUSIONS

In early-onset ARDS patients, most of the recruitment occurs during the first 10 s of a sustained inflation RM. However, hemodynamic impairment is significant after the tenth second of RM.

Recruitment maneuvers: using transpulmonary pressure to help Goldilocks.

Baedorf Kassis E, Loring SH, Talmor D. Recruitment maneuvers: using transpulmonary pressure to help Goldilocks. Intensive Care Med. 2017;43(8):1162-1163. doi:10.1007/s00134-017-4784-2