Comparative effects of flow vs. volume-controlled one-lung ventilation on gas exchange and respiratory system mechanics in pigs
Autor: | Robert Huhle, Thea Koch, Thomas Bluth, Martin Scharffenberg, Raphael Theilen, Jakob Wittenstein, Marcelo Gama de Abreu, Thomas Kiss, Xi Ran, Diana Keller, S. Tauer, Pia Michler |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2020 |
Předmět: |
Respiratory rate
VILI medicine.medical_treatment Hemodynamics Critical Care and Intensive Care Medicine Hypoxemia 03 medical and health sciences 0302 clinical medicine 030202 anesthesiology OLV Medicine Thoracotomy Respiratory system Mechanical power Mechanical ventilation business.industry Research lcsh:Medical emergencies. Critical care. Intensive care. First aid 030208 emergency & critical care medicine Oxygenation lcsh:RC86-88.9 Thoracic surgery Normovolaemia FCV Anesthesia Intravascular hypovolaemia medicine.symptom business Resistive mechanical power Respiratory minute volume |
Zdroj: | Intensive Care Medicine Experimental, Vol 8, Iss S1, Pp 1-16 (2020) Intensive Care Medicine Experimental |
Popis: | Background Flow-controlled ventilation (FCV) allows expiratory flow control, reducing the collapse of the airways during expiration. The performance of FCV during one-lung ventilation (OLV) under intravascular normo- and hypovolaemia is currently unknown. In this explorative study, we hypothesised that OLV with FCV improves PaO2 and reduces mechanical power compared to volume-controlled ventilation (VCV). Sixteen juvenile pigs were randomly assigned to one of two groups: (1) intravascular normovolaemia (n = 8) and (2) intravascular hypovolaemia (n = 8). To mimic inflammation due to major thoracic surgery, a thoracotomy was performed, and 0.5 μg/kg/h lipopolysaccharides from Escherichia coli continuously administered intravenously. Animals were randomly assigned to OLV with one of two sequences (60 min per mode): (1) VCV–FCV or (2) FCV–VCV. Variables of gas exchange, haemodynamics and respiratory signals were collected 20, 40 and 60 min after initiation of OLV with each mechanical ventilation mode. The distribution of ventilation was determined using electrical impedance tomography (EIT). Results Oxygenation did not differ significantly between modes (P = 0.881). In the normovolaemia group, the corrected expired minute volume (P = 0.022) and positive end-expiratory pressure (PEEP) were lower during FCV than VCV. The minute volume (P ≤ 0.001), respiratory rate (P ≤ 0.001), total PEEP (P ≤ 0.001), resistance of the respiratory system (P ≤ 0.001), mechanical power (P ≤ 0.001) and resistive mechanical power (P ≤ 0.001) were lower during FCV than VCV irrespective of the volaemia status. The distribution of ventilation did not differ between both ventilation modes (P = 0.103). Conclusions In a model of OLV in normo- and hypovolemic pigs, mechanical power was lower during FCV compared to VCV, without significant differences in oxygenation. Furthermore, the efficacy of ventilation was higher during FCV compared to VCV during normovolaemia. |
Databáze: | OpenAIRE |
Externí odkaz: |