scholarly journals Effect of mechanical pressure-controlled ventilation in patients with disturbed respiratory function during laparoscopic cholecystectomy

2013 ◽  
Vol 70 (1) ◽  
pp. 9-15
Author(s):  
Maja Surbatovic ◽  
Zoran Vesic ◽  
Dragan Djordjevic ◽  
Sonja Radakovic ◽  
Snjezana Zeba ◽  
...  

Background/Aim: Laparoscopic cholecystectomy is considered to be the gold standard for laparoscopic surgical procedures. In ASA III patients with concomitant respiratory diseases, however, creation of pneumoperitoneum and the position of patients during surgery exert additional negative effect on intraoperative respiratory function, thus making a higher challenge for the anesthesiologist than for the surgeon. The aim of this study was to compare the effect of intermittent positive pressure ventilation (IPPV) and pressure controlled ventilation (PCV) during general anesthesia on respiratory function in ASA III patients submitted to laparoscopic cholecystectomy. Methods. The study included 60 patients randomized into two groups depending on the mode of ventilation: IPPV or PCV. Respiratory volume (VT), peak inspiratory pressure (PIP), compliance (C), end-tidal CO2 pressure (PETCO2), oxygen saturation (SpO2), partial pressures of O2, CO2 (PaO2 and PaCO2) and pH of arterial blood were recorded within four time intervals. Results. There were no statistically significant differences in VT, SpO2, PaO2, PaCO2 and pH values neither within nor between the two groups. In time interval t1 there were no statistically significant differences in PIP, C, PETCO2 values between the IPPV and the PCV group. But, in the next three time intervals there was a difference in PIP, C, and PETCO2 values between the two groups which ranged from statistically significant to highly significant; PIP was lower, C and PETCO2 were higher in the PCV group. Conclusion. Pressure controlled ventilation better maintains stability regarding intraoperative ventilatory parameters in ASA III patients with concomitant respiratory diseases during laparoscopic cholecystectomy.

2011 ◽  
Vol 110 (5) ◽  
pp. 1374-1383 ◽  
Author(s):  
Gaetano Perchiazzi ◽  
Christian Rylander ◽  
Antonio Vena ◽  
Savino Derosa ◽  
Debora Polieri ◽  
...  

During positive-pressure ventilation parenchymal deformation can be assessed as strain (volume increase above functional residual capacity) in response to stress (transpulmonary pressure). The aim of this study was to explore the relationship between stress and strain on the regional level using computed tomography in anesthetized healthy pigs in two postures and two patterns of breathing. Airway opening and esophageal pressures were used to calculate stress; change of gas content as assessed from computed tomography was used to calculate strain. Static stress-strain curves and dynamic strain-time curves were constructed, the latter during the inspiratory phase of volume and pressure-controlled ventilation, both in supine and prone position. The lung was divided into nondependent, intermediate, dependent, and central regions: their curves were modeled by exponential regression and examined for statistically significant differences. In all the examined regions, there were strong but different exponential relations between stress and strain. During mechanical ventilation, the end-inspiratory strain was higher in the dependent than in the nondependent regions. No differences between volume- and pressure-controlled ventilation were found. However, during volume control ventilation, prone positioning decreased the end-inspiratory strain of dependent regions and increased it in nondependent regions, resulting in reduced strain gradient. Strain is inhomogeneously distributed within the healthy lung. Prone positioning attenuates differences between dependent and nondependent regions. The regional effects of ventilatory mode and body positioning should be further explored in patients with acute lung injury.


2017 ◽  
Vol 38 (4) ◽  
pp. 2209
Author(s):  
Rodrigo Lima Carneiro ◽  
Patrícia Cristina Ferro Lopes ◽  
Ana Paula Gering ◽  
Eliselle Gouveia de Faria Biteli ◽  
Paloma Do Espírito Santo Silva ◽  
...  

This paper evaluated the effects of the ratio of nitrous oxide to oxygen (50% of each) on cardiovascular parameters in pigs anesthetized with propofol and maintained in ventilation with intermittent positive pressure. Sixteen Large White pigs, weighing between 15 and 20 kg, were divided into two groups of eight animals, and designated as follows: GPN (propofol/nitrous oxide) and GPA (propofol/compressed air). In order to allow endotracheal intubation, the animals received azaperone (2 mg kg-1, IM) followed, after 20 minutes, by intravenous propofol. After successful intubation, continuous infusion of propofol was initiated at a dose of 0.4 mg kg-1minute-1. From this point, the GPN group received N2O (diluted in 50% oxygen), while the GPA group received compressed air (diluted in 50% oxygen). Rocuronium was then administered by continuous intravenous infusion at 0.6 mg kg-1h-1. Pressure-controlled ventilation (PCV) was started and adjusted to 15 cmH2O, and the respiratory rate was set to reach capnometry readings between 35-45 mmHg. The measurement of parameters (heart rate, mean arterial pressure, cardiac index, systemic vascular resistance index, stroke index) begun 15 minutes after the administration of rocuronium, and was repeated in 15-minute intervals for 60 minutes. Data were statistically analyzed by ANOVA followed by Bonferroni test. The results showed that the 1:1 ratio combination of nitrous oxide to oxygen (50% each) did not alter the mentioned parameters in pigs anesthetized with propofol and maintained at pressure-controlled ventilation, indicating that it is a safe protocol for the cardiovascular system.


Author(s):  
Ferda Y. Inal ◽  
Yadigar Y. Camgoz ◽  
Hayrettin Daskaya ◽  
Oznur Sen

Background: This study aimed to compare the changes induced by VCV and PCV modes in hemodynamics, respiration (airway pressures, gas exchange parameters) and metabolism (acid-base balance) in patients undergoing laparoscopic cholecystectomy.Methods: Patients were divided into two randomised groups as volume-controlled ventilation (VCV) group (VC) and pressure-controlled ventilation (PCV) group (PC). The following parameters were recorded at 3 different time points: T1: in supine position 10 minutes after induction of anaesthesia, T2: 15 minutes after CO2 insufflation in inverted Trendelenburg position (head 30 degrees up), T3: 10 minutes after CO2 desufflation. HR, SpO2, SAP (systolic arterial pressure), DAP (diastolic arterial pressure), MAP (mean arterial pressure), PetCO2 (end-tidal carbon dioxide pressure), Ppeak, Pplateau, Pmean, Vt (tidal volume) and compliance with the available data, the cases in both groups Vd, Vd/Vt ratios and P(A-a)O2 were calculated. Arterial blood gas parameters (pH, PaO2, PaCO2, SaO2, P(a-et)CO2) values were recorded.Results: It was found that Ppeak and Pplateau values were significantly higher in the VC group (p<0.05). It was found that compliance was significantly higher in the PC group (p<0.05) (p<0.01). In the postoperative period, it was found that PaO2 values were significantly higher in the PC group compared to the VC group (p<0.05). It was found that the P(A-a)O2 values of the PC group were significantly higher than those of the VC group during the desufflation phase (p<0.05).Conclusions: We think that PCV mode can be a good alternative for the prevention and correction of physiopathological changes due to laparoscopic surgery.


2021 ◽  
Vol 10 (6) ◽  
pp. 1276
Author(s):  
Volker Schick ◽  
Fabian Dusse ◽  
Ronny Eckardt ◽  
Steffen Kerkhoff ◽  
Simone Commotio ◽  
...  

For perioperative mechanical ventilation under general anesthesia, modern respirators aim at combining the benefits of pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) in modes typically named “volume-guaranteed” or “volume-targeted” pressure-controlled ventilation (PCV-VG). This systematic review and meta-analysis tested the hypothesis that PCV-VG modes of ventilation could be beneficial in terms of improved airway pressures (Ppeak, Pplateau, Pmean), dynamic compliance (Cdyn), or arterial blood gases (PaO2, PaCO2) in adults undergoing elective surgery under general anesthesia. Three major medical electronic databases were searched with predefined search strategies and publications were systematically evaluated according to the Cochrane Review Methods. Continuous variables were tested for mean differences using the inverse variance method and 95% confidence intervals (CI) were calculated. Based on the assumption that intervention effects across studies were not identical, a random effects model was chosen. Assessment for heterogeneity was performed with the χ2 test and the I2 statistic. As primary endpoints, Ppeak, Pplateau, Pmean, Cdyn, PaO2, and PaCO2 were evaluated. Of the 725 publications identified, 17 finally met eligibility criteria, with a total of 929 patients recruited. Under supine two-lung ventilation, PCV-VG resulted in significantly reduced Ppeak (15 studies) and Pplateau (9 studies) as well as higher Cdyn (9 studies), compared with VCV [random effects models; Ppeak: CI −3.26 to −1.47; p < 0.001; I2 = 82%; Pplateau: −3.12 to −0.12; p = 0.03; I2 = 90%; Cdyn: CI 3.42 to 8.65; p < 0.001; I2 = 90%]. For one-lung ventilation (8 studies), PCV-VG allowed for significantly lower Ppeak and higher PaO2 compared with VCV. In Trendelenburg position (5 studies), this effect was significant for Ppeak only. This systematic review and meta-analysis demonstrates that volume-targeting, pressure-controlled ventilation modes may provide benefits with respect to the improved airway dynamics in two- and one-lung ventilation, and improved oxygenation in one-lung ventilation in adults undergoing elective surgery.


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