Abstract HTML Views: 169 PDF Downloads: 44 Total Views/Downloads: 213
Abstract HTML Views: 135 PDF Downloads: 38 Total Views/Downloads: 173
The goal of Basic Life Support is the oxygenation of vital organs during cardiac arrest. Therefore,
chest compressions are combined with ventilation in a fixed ratio. This study investigated the influence of bag/mask ventilation
on pulmonary gas exchange in anaesthetized patients performed with a ventilation/compression ratio of 2:15 compared
Forty patients scheduled for elective cardiac surgery received general anesthesia (Propofol/Sufentanil/ Rocuronium).
Upon loss of consciousness bag/mask ventilation was started (15l/min O2 with reservoir bag) over a six minute
period using either 2 ventilations every 9 seconds (simulated ventilation/compression ratio 2:15) or 5 ventilations every 30
seconds (simulated ventilation/compression ratio 5:50). Arterial blood gas sampling was performed at beginning of ventilation
and after six minutes. Data were analyzed with 2-factorial ANOVA.
Arterial PO2 increased in both groups during the ventilation with pure oxygen (PaO2: 2:15 group: 259 mmHg [0
min], 369 mmHg [6 min]; 5:50 group: 277 mmHg [0 min], 363 mmHg [6 min]; n.s.). Arterial pCO2 also increased
(PaCO2: 2:15 group: 47 mmHg [0min], 48 mmHg [6min]; 5:50 group: 47 mmHg [0min], 52 mmHg [6min], P=0,018).
Consequently, pH decreased in both groups (pH: 2:15 group; 7,37 [0min], 7,36[6min]; 5:50 group: 7,38 [0min], 7,34
[6min], P=0,02). There was no critical decrease of SpO2 at any time.
In the anesthetized patient with spontaneous circulation bag/mask ventilation simulating ventilation/compression
ratios of 2:15 and 5:50 enable an adequate oxygenation and stable acid base balance.