Variable versus conventional lung protective mechanical ventilation during open abdominal surgery: study protocol for a randomized controlled trial

Peter M Spieth, Andreas Güldner, Christopher Uhlig, Thomas Bluth, Thomas Kiss, Marcus J Schultz, Paolo Pelosi, Thea Koch, Marcelo Gama de Abreu, Peter M Spieth, Andreas Güldner, Christopher Uhlig, Thomas Bluth, Thomas Kiss, Marcus J Schultz, Paolo Pelosi, Thea Koch, Marcelo Gama de Abreu

Abstract

Background: General anesthesia usually requires mechanical ventilation, which is traditionally accomplished with constant tidal volumes in volume- or pressure-controlled modes. Experimental studies suggest that the use of variable tidal volumes (variable ventilation) recruits lung tissue, improves pulmonary function and reduces systemic inflammatory response. However, it is currently not known whether patients undergoing open abdominal surgery might benefit from intraoperative variable ventilation.

Methods/design: The PROtective VARiable ventilation trial ('PROVAR') is a single center, randomized controlled trial enrolling 50 patients who are planning for open abdominal surgery expected to last longer than 3 hours. PROVAR compares conventional (non-variable) lung protective ventilation (CV) with variable lung protective ventilation (VV) regarding pulmonary function and inflammatory response. The primary endpoint of the study is the forced vital capacity on the first postoperative day. Secondary endpoints include further lung function tests, plasma cytokine levels, spatial distribution of ventilation assessed by means of electrical impedance tomography and postoperative pulmonary complications.

Discussion: We hypothesize that VV improves lung function and reduces systemic inflammatory response compared to CV in patients receiving mechanical ventilation during general anesthesia for open abdominal surgery longer than 3 hours. PROVAR is the first randomized controlled trial aiming at intra- and postoperative effects of VV on lung function. This study may help to define the role of VV during general anesthesia requiring mechanical ventilation.

Trial registration: Clinicaltrials.gov NCT01683578 (registered on September 3 3012).

Figures

Figure 1
Figure 1
CONSORT diagram for the PROVAR trial. VT, tidal volume; CV VT, coefficient of variation of tidal volume.

References

    1. Hedenstierna G, Tokics L, Strandberg A, Lundquist H, Brismar B. Correlation of gas exchange impairment to development of atelectasis during anaesthesia and muscle paralysis. Acta Anaesthesiol Scand. 1986;30:183–191. doi: 10.1111/j.1399-6576.1986.tb02393.x.
    1. Xue FS, Li BW, Zhang GS, Liao X, Zhang YM, Liu JH, An G, Luo LK. The influence of surgical sites on early postoperative hypoxemia in adults undergoing elective surgery. Anesth Analg. 1999;88:213–219.
    1. von Ungern-Sternberg BS, Regli A, Reber A, Schneider MC. Comparison of perioperative spirometric data following spinal or general anaesthesia in normal-weight and overweight gynaecological patients. Acta Anaesthesiol Scand. 2005;49:940–948. doi: 10.1111/j.1399-6576.2005.00754.x.
    1. Golfieri R, Giampalma E, Morselli Labate AM, D’ Arienzo P, Jovine E, Grazi GL, Mazziotti A, Maffei M, Muzzi C, Tancioni S, Sama C, Cavallari A, Gavelli G. Pulmonary complications of liver transplantation: radiological appearance and statistical evaluation of risk factors in 300 cases. Eur Radiol. 2000;10:1169–1183. doi: 10.1007/s003309900268.
    1. van Kaam AH, Lachmann RA, Herting E, De Jaegere A, van Iwaarden F, Noorduyn LA, Kok JH, Haitsma JJ, Lachmann B. Reducing atelectasis attenuates bacterial growth and translocation in experimental pneumonia. Am J Respir Crit Care Med. 2004;169:1046–1053. doi: 10.1164/rccm.200312-1779OC.
    1. Pelosi P, Rocco PR. Airway closure: the silent killer of peripheral airways. Crit Care. 2007;11:114. doi: 10.1186/cc5692.
    1. Rosenberg J, Rasmussen V, von Jessen F, Ullstad T, Kehlet H. Late postoperative episodic and constant hypoxaemia and associated ECG abnormalities. Br J Anaesth. 1990;65:684–691. doi: 10.1093/bja/65.5.684.
    1. Gill NP, Wright B, Reilly CS. Relationship between hypoxaemic and cardiac ischaemic events in the perioperative period. Br J Anaesth. 1992;68:471–473. doi: 10.1093/bja/68.5.471.
    1. Severgnini P, Selmo G, Lanza C, Chiesa A, Frigerio A, Bacuzzi A, Dionigi G, Novario R, Gregoretti C, de Abreu MG, Schultz MJ, Jaber S, Futier E, Chiaranda M, Pelosi P. Protective mechanical ventilation during general anesthesia for open abdominal surgery improves postoperative pulmonary function. Anesthesiology. 2013;118:1307–1321. doi: 10.1097/ALN.0b013e31829102de.
    1. Tokics L, Hedenstierna G, Strandberg A, Brismar B, Lundquist H. Lung collapse and gas exchange during general anesthesia: effects of spontaneous breathing, muscle paralysis, and positive end-expiratory pressure. Anesthesiology. 1987;66:157–167. doi: 10.1097/00000542-198702000-00009.
    1. Spieth PM, Carvalho AR, Pelosi P, Hoehn C, Meissner C, Kasper M, Hubler M, von Neindorff M, Dassow C, Barrenschee M, Uhlig S, Koch T, Gama de Abreu M. Variable tidal volumes improve lung protective ventilation strategies in experimental lung injury. Am J Respir Crit Care Med. 2009;179:684–693. doi: 10.1164/rccm.200806-975OC.
    1. Boker A, Haberman CJ, Girling L, Guzman RP, Louridas G, Tanner JR, Cheang M, Maycher BW, Bell DD, Doak GJ. Variable ventilation improves perioperative lung function in patients undergoing abdominal aortic aneurysmectomy. Anesthesiology. 2004;100:608–616. doi: 10.1097/00000542-200403000-00022.
    1. Mutch WA, Harms S, Ruth Graham M, Kowalski SE, Girling LG, Lefevre GR. Biologically variable or naturally noisy mechanical ventilation recruits atelectatic lung. Am J Respir Crit Care Med. 2000;162:319–323. doi: 10.1164/ajrccm.162.1.9903120.
    1. Bellardine CL, Hoffman AM, Tsai L, Ingenito EP, Arold SP, Lutchen KR, Suki B. Comparison of variable and conventional ventilation in a sheep saline lavage lung injury model. Crit Care Med. 2006;34:439–445. doi: 10.1097/01.CCM.0000196208.01682.87.
    1. Spieth PM, Guldner A, Beda A, Carvalho N, Nowack T, Krause A, Rentzsch I, Suchantke S, Thal SC, Engelhard K, Kasper M, Koch T, Pelosi P, Gama de Abreu M. Comparative effects of proportional assist and variable pressure support ventilation on lung function and damage in experimental lung injury. Crit Care Med. 2012;40:2654–2661. doi: 10.1097/CCM.0b013e3182592021.
    1. Lefevre GR, Kowalski SE, Girling LG, Thiessen DB, Mutch WA. Improved arterial oxygenation after oleic acid lung injury in the pig using a computer-controlled mechanical ventilator. Am J Respir Crit Care Med. 1996;154:1567–1572. doi: 10.1164/ajrccm.154.5.8912782.
    1. Suki B, Alencar AM, Sujeer MK, Lutchen KR, Collins JJ, Andrade JS Jr, Ingenito EP, Zapperi S, Stanley HE. Life-support system benefits from noise. Nature. 1998;393:127–128.
    1. Gama de Abreu M, Spieth PM, Pelosi P, Carvalho AR, Walter C, Schreiber-Ferstl A, Aikele P, Neykova B, Hubler M, Koch T. Noisy pressure support ventilation: a pilot study on a new assisted ventilation mode in experimental lung injury. Crit Care Med. 2008;36:818–827. doi: 10.1097/01.CCM.0000299736.55039.3A.
    1. Spieth PM, Carvalho AR, Guldner A, Kasper M, Schubert R, Carvalho NC, Beda A, Dassow C, Uhlig S, Koch T, Pelosi P, Gama de Abreu M. Pressure support improves oxygenation and lung protection compared to pressure-controlled ventilation and is further improved by random variation of pressure support. Crit Care Med. 2011;39:746–755. doi: 10.1097/CCM.0b013e318206bda6.
    1. Froehlich KF, Graham MR, Buchman TG, Girling LG, Scafetta N, West BJ, Walker EK, McManus BM, Mutch WA. Physiological noise versus white noise to drive a variable ventilator in a porcine model of lung injury. Can J Anaesth. 2008;55:577–586. doi: 10.1007/BF03021431.
    1. Tobin MJ, Chadha TS, Jenouri G, Birch SJ, Gazeroglu HB, Sackner MA. Breathing patterns. 2. Diseased subjects. Chest. 1983;84:286–294.
    1. Tobin MJ, Chadha TS, Jenouri G, Birch SJ, Gazeroglu HB, Sackner MA. Breathing patterns. 1. Normal subjects. Chest. 1983;84:202–205. doi: 10.1378/chest.84.2.202.
    1. Spieth PM, Carvalho AR, Guldner A, Pelosi P, Kirichuk O, Koch T, de Abreu MG. Effects of different levels of pressure support variability in experimental lung injury. Anesthesiology. 2009;110:342–350.
    1. Arold SP, Suki B, Alencar AM, Lutchen KR, Ingenito EP. Variable ventilation induces endogenous surfactant release in normal guinea pigs. Am J Physiol Lung Cell Mol Physiol. 2003;285:L370–L375. doi: 10.1152/ajpcell.00453.2002.
    1. Thammanomai A, Hueser LE, Majumdar A, Bartolak-Suki E, Suki B. Design of a new variable-ventilation method optimized for lung recruitment in mice. J Appl Physiol. 2008;104:1329–1340. doi: 10.1152/japplphysiol.01002.2007.
    1. Ma B, Suki B, Bates JH. Effects of recruitment/derecruitment dynamics on the efficacy of variable ventilation. J Appl Physiol. 2011;110:1319–1326. doi: 10.1152/japplphysiol.01364.2010.
    1. Carvalho AR, Spieth PM, Guldner A, Cuevas M, Carvalho NC, Beda A, Spieth S, Stroczynski C, Wiedemann B, Koch T, Pelosi P, Gama de Abreu M. Distribution of regional lung aeration and perfusion during conventional and noisy pressure support ventilation in experimental lung injury. J Appl Physiol. 2011;110:1083–1092. doi: 10.1152/japplphysiol.00804.2010.
    1. Kowalski S, McMullen MC, Girling LG, McCarthy BG. Biologically variable ventilation in patients with acute lung injury: a pilot study. Can J Anaesth. 2013;60:502–503. doi: 10.1007/s12630-013-9899-5.

Source: PubMed

3
Sottoscrivi