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Volume-controlled versus pressure-controlled ventilation-volume guaranteed mode during one-lung ventilation.

Song SY, Jung JY, Cho MS, Kim JH, Ryu TH, Kim BI - Korean J Anesthesiol (2014)

Bottom Line: Ppeak was significantly reduced with the PCV-VG mode (19.6 ± 2.5 cmH2O) compared with the VCV mode (23.2 ± 3.1 cmH2O) (P < 0.000).The exhaled TV was also significantly increased in PCV-VG compared with VCV (451.4 ± 85.4 vs. 443.9 ± 85.9 ml; P = 0.035).During OLV in patients with normal lung function, although PCV-VG did not provide significantly improved arterial oxygen tension compared with VCV, PCV-VG provided significantly attenuated airway pressure despite significantly increased exhaled TV compared with VCV.

View Article: PubMed Central - PubMed

Affiliation: Department of Anesthesiology and Pain Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.

ABSTRACT

Background: The purpose of this study was to investigate the changes in airway pressure and arterial oxygenation between ventilation modes during one-lung ventilation (OLV) in patients undergoing thoracic surgery.

Methods: We enrolled 27 patients for thoracic surgery with OLV in the lateral decubitus position. The subjects received various modes of ventilation in random sequences during surgery, including volume-controlled ventilation (VCV) and pressure-controlled ventilation-volume guaranteed (PCV-VG) with a tidal volume (TV) of 8 ml/kg of actual body weight. Target-controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. After double-lumen endobronchial tube (DLT) insertion, the proper positioning of the DLT was assessed using a fiberoptic bronchoscope. Peak inspiratory pressure (Ppeak), exhaled TV, and arterial blood gas were measured 30 min after each ventilation mode.

Results: Ppeak was significantly reduced with the PCV-VG mode (19.6 ± 2.5 cmH2O) compared with the VCV mode (23.2 ± 3.1 cmH2O) (P < 0.000). However, no difference in arterial oxygen tension was noted between the groups (PCV-VG, 375.8 ± 145.1 mmHg; VCV, 328.1 ± 123.7 mmHg) (P = 0.063). The exhaled TV was also significantly increased in PCV-VG compared with VCV (451.4 ± 85.4 vs. 443.9 ± 85.9 ml; P = 0.035).

Conclusions: During OLV in patients with normal lung function, although PCV-VG did not provide significantly improved arterial oxygen tension compared with VCV, PCV-VG provided significantly attenuated airway pressure despite significantly increased exhaled TV compared with VCV.

No MeSH data available.


Related in: MedlinePlus

Consort diagram depicts the flow of participants.
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Figure 1: Consort diagram depicts the flow of participants.

Mentions: We began this study after receiving approval from the Institutional Review Board of our hospital and obtaining informed consent from all the patients. Twenty-seven patients who were classified as American Society of Anesthesiologists physical status 1 and 2 and underwent thoracic surgery in the lateral decubitus position with at least 1 h OLV were enrolled (Table 1, Fig. 1). The exclusion criteria were previous lobectomy, uncompensated cardiac disease, tracheostomy state, and predicted forced expiratory volume in 1 second (FEV1) below 70%. All patients were intramuscularly injected with 0.2 mg glycopyrrolate and 1 mg midazolam as premedication 30 min before arriving in the operating room. The patients were furnished with electrocardiogram (ECG), noninvasive blood pressure, pulse oximetry, and bispectral index (BIS) monitoring equipment before the induction of anesthesia. Anesthesia was induced and maintained with an effect-site concentration of 4 µg/ml propofol and 4 ng/ml remifentanil using target controlled infusion (TCI). After loss of consciousness, 0.6 mg/kg rocuronium was administered for intubation, and 0.08 mg/kg/hr vecuronium infusion was followed 30 min after intubation. All patients were intubated with a double-lumen endobronchial tube (DLT, Silbroncho®, Fuji System Corp, Tokyo, Japan), and the proper position of the DLT was confirmed using a fiberoptic bronchoscope. All of the patients were intubated with left-side DLT if there was no contraindication. After intubation, a radial artery cannulation was performed on the contralateral side arm of the operation, and a central venous catheter was placed in the ipsilateral subclavian vein. Initially, two-lung ventilation with VCV was performed using 1.0 fraction of inspired oxygen concentration (FiO2), a TV of 8 ml/kg of actual body weight, and 12 /min respiration rate. The respiration rate was adjusted to maintain an end-tidal carbon dioxide concentration (ETCO2) of 35-40 mmHg. After changing the patient to a lateral decubitus position, the location of the DLT was reassessed with a fiberoptic bronchoscope. OLV was subsequently performed with VCV or PCV-VG (Avance, GE healthcare, Wauwatosa, WI, USA) according to an allocation sequence. An independent statistician randomized the ventilation sequence using a computerized random number generator. VCV was set to deliver a TV of 8 ml/kg of actual body weight without positive end-expiratory pressure (PEEP), and the respiration rate was adjusted to maintain an ETCO2 of 35-40 mmHg using 1.0 FiO2. The maximum airway pressure (Pmax), at which time the ventilator will alarm and end inspiration, was adjusted to 40 cmH2O. An inspiration to expiration ratio of 1 : 2 was used, and no inspiratory time pause was used. PCV-VG was performed using 1.0 FiO2, a TV of 8 ml/kg of actual body weight without PEEP, 40 cmH2O Pmax, and an inspiration to expiration ratio of 1 : 2; the respiration rate was adjusted to maintain an ETCO2 of 35-40 mmHg. The rise rate, which indicates how quickly the ventilator reaches the targeted airway pressure, was adjusted to 5 sec. In the PCV-VG mode, the present anesthetic machine delivers the first breath to the patient using a VCV setting to identify the patient's lung compliance, and then the inspiratory pressure level is automatically calculated and determined for the subsequent breaths in the PCV-VG setting. The Ppeak, mean inspiratory pressure (Pmean), TVE, systolic and diastolic blood pressures (SBP, DBP), heart rate (HR), arterial oxygen tension (PaO2), and arterial carbon dioxide tension (PaCO2) were measured and recorded after performing each mode of mechanical ventilation for 30 min in the lateral decubitus position. Afterwards, the ventilation was changed to another mode and maintained until the surgery was completed. When the ventilation mode was changed from VCV to PCV-VG or from PCV-VG to VCV 30 min after OLV, the TV and respiration rate of the previous mode were maintained. Thirty minutes after changing the ventilation mode, all measurements were performed again. When the peripheral oxygen saturation (SpO2) decreased below 90% or PaO2 decreased below 80 mmHg, both of which are defined as hypoxemia, the experiment was terminated. When hypoxemia occurred, two-lung ventilation with 1.0 FiO2 was performed, and the patient was excluded from this study. Hypoxemia was treated according to standard hypoxemia treatment protocols, including DLT position readjustment using a fiberoptic bronchoscope, lung recruitment maneuver, change of TV, and the application of PEEP or continuous positive airway pressure.


Volume-controlled versus pressure-controlled ventilation-volume guaranteed mode during one-lung ventilation.

Song SY, Jung JY, Cho MS, Kim JH, Ryu TH, Kim BI - Korean J Anesthesiol (2014)

Consort diagram depicts the flow of participants.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4216788&req=5

Figure 1: Consort diagram depicts the flow of participants.
Mentions: We began this study after receiving approval from the Institutional Review Board of our hospital and obtaining informed consent from all the patients. Twenty-seven patients who were classified as American Society of Anesthesiologists physical status 1 and 2 and underwent thoracic surgery in the lateral decubitus position with at least 1 h OLV were enrolled (Table 1, Fig. 1). The exclusion criteria were previous lobectomy, uncompensated cardiac disease, tracheostomy state, and predicted forced expiratory volume in 1 second (FEV1) below 70%. All patients were intramuscularly injected with 0.2 mg glycopyrrolate and 1 mg midazolam as premedication 30 min before arriving in the operating room. The patients were furnished with electrocardiogram (ECG), noninvasive blood pressure, pulse oximetry, and bispectral index (BIS) monitoring equipment before the induction of anesthesia. Anesthesia was induced and maintained with an effect-site concentration of 4 µg/ml propofol and 4 ng/ml remifentanil using target controlled infusion (TCI). After loss of consciousness, 0.6 mg/kg rocuronium was administered for intubation, and 0.08 mg/kg/hr vecuronium infusion was followed 30 min after intubation. All patients were intubated with a double-lumen endobronchial tube (DLT, Silbroncho®, Fuji System Corp, Tokyo, Japan), and the proper position of the DLT was confirmed using a fiberoptic bronchoscope. All of the patients were intubated with left-side DLT if there was no contraindication. After intubation, a radial artery cannulation was performed on the contralateral side arm of the operation, and a central venous catheter was placed in the ipsilateral subclavian vein. Initially, two-lung ventilation with VCV was performed using 1.0 fraction of inspired oxygen concentration (FiO2), a TV of 8 ml/kg of actual body weight, and 12 /min respiration rate. The respiration rate was adjusted to maintain an end-tidal carbon dioxide concentration (ETCO2) of 35-40 mmHg. After changing the patient to a lateral decubitus position, the location of the DLT was reassessed with a fiberoptic bronchoscope. OLV was subsequently performed with VCV or PCV-VG (Avance, GE healthcare, Wauwatosa, WI, USA) according to an allocation sequence. An independent statistician randomized the ventilation sequence using a computerized random number generator. VCV was set to deliver a TV of 8 ml/kg of actual body weight without positive end-expiratory pressure (PEEP), and the respiration rate was adjusted to maintain an ETCO2 of 35-40 mmHg using 1.0 FiO2. The maximum airway pressure (Pmax), at which time the ventilator will alarm and end inspiration, was adjusted to 40 cmH2O. An inspiration to expiration ratio of 1 : 2 was used, and no inspiratory time pause was used. PCV-VG was performed using 1.0 FiO2, a TV of 8 ml/kg of actual body weight without PEEP, 40 cmH2O Pmax, and an inspiration to expiration ratio of 1 : 2; the respiration rate was adjusted to maintain an ETCO2 of 35-40 mmHg. The rise rate, which indicates how quickly the ventilator reaches the targeted airway pressure, was adjusted to 5 sec. In the PCV-VG mode, the present anesthetic machine delivers the first breath to the patient using a VCV setting to identify the patient's lung compliance, and then the inspiratory pressure level is automatically calculated and determined for the subsequent breaths in the PCV-VG setting. The Ppeak, mean inspiratory pressure (Pmean), TVE, systolic and diastolic blood pressures (SBP, DBP), heart rate (HR), arterial oxygen tension (PaO2), and arterial carbon dioxide tension (PaCO2) were measured and recorded after performing each mode of mechanical ventilation for 30 min in the lateral decubitus position. Afterwards, the ventilation was changed to another mode and maintained until the surgery was completed. When the ventilation mode was changed from VCV to PCV-VG or from PCV-VG to VCV 30 min after OLV, the TV and respiration rate of the previous mode were maintained. Thirty minutes after changing the ventilation mode, all measurements were performed again. When the peripheral oxygen saturation (SpO2) decreased below 90% or PaO2 decreased below 80 mmHg, both of which are defined as hypoxemia, the experiment was terminated. When hypoxemia occurred, two-lung ventilation with 1.0 FiO2 was performed, and the patient was excluded from this study. Hypoxemia was treated according to standard hypoxemia treatment protocols, including DLT position readjustment using a fiberoptic bronchoscope, lung recruitment maneuver, change of TV, and the application of PEEP or continuous positive airway pressure.

Bottom Line: Ppeak was significantly reduced with the PCV-VG mode (19.6 ± 2.5 cmH2O) compared with the VCV mode (23.2 ± 3.1 cmH2O) (P < 0.000).The exhaled TV was also significantly increased in PCV-VG compared with VCV (451.4 ± 85.4 vs. 443.9 ± 85.9 ml; P = 0.035).During OLV in patients with normal lung function, although PCV-VG did not provide significantly improved arterial oxygen tension compared with VCV, PCV-VG provided significantly attenuated airway pressure despite significantly increased exhaled TV compared with VCV.

View Article: PubMed Central - PubMed

Affiliation: Department of Anesthesiology and Pain Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.

ABSTRACT

Background: The purpose of this study was to investigate the changes in airway pressure and arterial oxygenation between ventilation modes during one-lung ventilation (OLV) in patients undergoing thoracic surgery.

Methods: We enrolled 27 patients for thoracic surgery with OLV in the lateral decubitus position. The subjects received various modes of ventilation in random sequences during surgery, including volume-controlled ventilation (VCV) and pressure-controlled ventilation-volume guaranteed (PCV-VG) with a tidal volume (TV) of 8 ml/kg of actual body weight. Target-controlled infusion (TCI) with propofol and remifentanil was used for anesthesia induction and maintenance. After double-lumen endobronchial tube (DLT) insertion, the proper positioning of the DLT was assessed using a fiberoptic bronchoscope. Peak inspiratory pressure (Ppeak), exhaled TV, and arterial blood gas were measured 30 min after each ventilation mode.

Results: Ppeak was significantly reduced with the PCV-VG mode (19.6 ± 2.5 cmH2O) compared with the VCV mode (23.2 ± 3.1 cmH2O) (P < 0.000). However, no difference in arterial oxygen tension was noted between the groups (PCV-VG, 375.8 ± 145.1 mmHg; VCV, 328.1 ± 123.7 mmHg) (P = 0.063). The exhaled TV was also significantly increased in PCV-VG compared with VCV (451.4 ± 85.4 vs. 443.9 ± 85.9 ml; P = 0.035).

Conclusions: During OLV in patients with normal lung function, although PCV-VG did not provide significantly improved arterial oxygen tension compared with VCV, PCV-VG provided significantly attenuated airway pressure despite significantly increased exhaled TV compared with VCV.

No MeSH data available.


Related in: MedlinePlus