Ventilation mode for resuscitation
Revolutionary technique from WEINMANN Emergency
For decades, ventilation with continuous chest compressions has presented a challenge in CPR. This is because in addition to the need to maintain both the circulation of blood and perfusion, blood requires the best possible oxygenation.
This is hard to implement, especially with significantly reduced cardiac output. The largely non-standard techniques which have been in use up to now have a risk of less than optimal ventilation because of complex settings and thus the possibility of operating errors.
This is where CCSV comes in: Simple to operate and perfectly integrated in the resuscitation sequence, MEDUMAT Standard² in CCSV mode ensures optimal oxygenation and decarboxylation of blood during CPR!
How CCSV works
Synchronizing heart and lungs during CPR
In conventional ventilation, the heart and the pulmonary vessels in the thorax are compressed during chest compressions, but the rise in intrathoracic pressure causes air to escape from the lungs, inhibiting the effect of pressure buildup and thus reducing cardiac output.
In ventilation during CPR under CCSV, a pressure-controlled mechanical breath is executed to synchronize with the chest compression performed, preventing any volume of gas escaping from the thorax; the increased pressure in the lungs ensures more vigorous compression of the heart during chest compressions. Cardiac output rises, ensuring improved gas exchange.
In the decompression phase, the device automatically switches to expiration to force air out of the lungs. At the same time, intrathoracic pressure drops and venous return to the heart proceeds unhindered.
Improved hemodynamics and oxygenation
Increasing intrathoracic pressure increases arterial blood pressure and the difference between arterial and central venous blood pressure (see Figure 1). This is crucial for cardiac and cerebral perfusion pressure.
A study [1] looked into CPR under CCSV compared to IPPV and BiLevel (BiPAP) in terms of gas exchange and hemodynamics. It demonstrated that CPR in CCSV mode leads to improved oxygenation, a normal venous pH and a significantly higher arterial blood pressure. CCSV thus makes a positive contribution to hemodynamics.
Adequate alveolar ventilation
In addition to maintaining perfusion and oxygenation, the elimination of CO2 plays a key role in CPR. To prevent respiratory acidosis, it is important to maintain the partial pressure of carbon dioxide at as normal a value as possible.
The effect of CCSV on the arterial partial pressure of carbon dioxide during CPR was examined in a further study [3]. Continuous administration of low tidal volumes above dead space volume under CCSV ensures that neither hypoventilation nor hyperventilation occur. As can be seen in Figure 2, it is possible to achieve normocapnia during CPR with CCSV, allowing us to draw the conclusion that CCSV can prevent hypercapnia and thus prevent respiratory acidosis.
Improved cerebral oxygenation
Another interesting aspect is the effect of CCSV on cerebral oxygenation during CPR. A study [4] continuously measured the oxygen saturation of cerebral tissue (ScO2) during CPR (see Figure 3). This showed that under CCSV ventilation, it was possible to stop ScO2 dropping to below the initial value, even without administering adrenaline (t = 6 min). This suggests that CCSV improves cerebral oxygenation compared to IPPV.
Samples of lung tissue were also examined for morphological indications of ventilator-associated lung injury (VALI). In terms of potential damage to lung tissue, there were no differences between IPPV and CCSV.
Uninterrupted chest compressions
During CPR, chest compressions are interrupted in favor of manual ventilation. This leads to a drop in cardiac blood flow and has a potentially negative impact on the efficacy of resuscitation – a drawback which could affect your patients’ survival! This is why the ILCOR guidelines recommend performing uninterrupted chest compressions on patients as quickly as possible.
Once the airway has been secured, CCSV provides a remedy for this. MEDUMAT Standard² detects every chest compression automatically. If ventilation during CPR is performed in CCSV mode, the device triggers a mechanical breath to synchronize with every chest compression. Users can perform chest compressions without interruption. A frequency tachometer helps users maintain the optimum compression frequency.
Easily integrated in the resuscitation technique
At the emergency site, users commence CPR using the 30:2 technique as usual. Once the patient’s airway is secured by an endotracheal tube, you can switch to CCSV mode. Whilst users perform uninterrupted chest compressions, MEDUMAT Standard² in CCSV mode ensures adequate ventilation at every point.
Scientific information about CCSV
CCSV is the result of our many years’ experience in the field of emergency and transport ventilation and our participation in various scientific research projects. We have drafted a white paper which summarizes information about CCSV from scientific publications. Delve deeper into this topic to learn more about the benefits of CCSV.
Tidal volume
Tidal volume - volume delivered per mechanical breath
Hands-off time
time since last chest compression detected
etCO₂
If applicable, representation of the etCO₂
Trigger
sensitivity setting for compression detection
Type of compression
switch between manual and mechanical CPR at the touch of a button
PEEP
setting for positive end-expiratory pressure in the lungs. A higher PEEP may lead to better compression detection (can be set from 0 to 5 mbar)
Frequency tachometer
shows current compression rate per minute
Flow curve
displays the patient’s inspiration and expiration. “L” marks compressions detected and thus the trigger for ventilation
Sources
[1] Kill C, et al. Mechanical ventilation during cardiopulmonary resuscitation with intermittent positive-pressure ventilation, bilevel ventilation, or chest compression synchronized ventilation in a pig model. Crit Care Med. 2014 Feb;42(2):e89-95.
[2] WEINMANN Emergency Medical Technology GmbH + Co. KG: White Paper Chest Compression Synchronized Ventilation, 04/2020.
[3] Dersch W et al. Resuscitation and mechanical ventilation with Chest Compression Synchronized Ventilation (CCSV) or Intermitted Positive Pressure Ventilation (IPPV). Influence on gas exchange and return of spontaneous circulation in a pig model. https://doi.org/10.1016/j.resuscitation.2012.08.010
[4] Kill C, et al. Cerebral oxygenation during resuscitation: Influence of the ventilation modes Chest Compression Synchronized Ventilation (CCSV) or Intermitted Positive Pressure Ventilation (IPPV) and of vasopressors on cerebral tissue oxygen saturation. https://doi.org/10.1016/j.resuscitation.2015.09.101
[5] Kill C, et al: Mechanical positive pressure ventilation during resuscitation in out-of-hospital cardiac arrest with chest compression synchronized ventilation (CCSV) In: Resuscitation 142, e42, https://doi.org/10.1016/j.resuscitation.2019.06.102
[6] WEINMANN Emergency Medical Technology GmbH + Co. KG: Ergebnisse einer Befragung im Rahmen der klinischen Nachbeobachtung von CCSV, 10/2019.
[7] WEINMANN Emergency Medical Technology GmbH + Co. KG: Auswertung der internen Kundendatenbank, 10/2019.
[8] Wnent J, et al: Außerklinische Reanimation 2018 des Deutschen Reanimationsregisters In: Anästh Intensivmed, 2019;60:1-3, www.reanimationsregister.de/downloads/oeffentliche-jahresberichte/rettungsdienst/142-2019-ausserklinischer-jahresbericht-2018/file.html