Critical Care Medicine  |   July 2020
Mechanical Ventilation Guided by Uncalibrated Esophageal Pressure May Be Potentially Harmful
Author Notes
  • From the Department of Anesthesiology and Intensive Care, Maggiore della Carità University Hospital, Novara, Italy (G.C., I.S., R.P.); Department of Translational Medicine, Eastern Piedmont University, Novara, Italy (G.L., E.S., F.V., E.Boniolo, R.T., F.D.C., R.V.); Anesthesiology, Critical Care, and Pain Medicine Division, Department of Medicine and Surgery, University of Parma, Parma, Italy (E.Bignami); Anesthesia and Intensive Care, Policlinico S. Matteo IRCCS Foundation, Pavia, Italy (S.M., A.O., F.M.); and Department of Clinical-Surgical, Diagnostic and Pediatric Sciences, Unit of Anaesthesia and Intensive Care, University of Pavia, Pavia, Italy (E.A., F.M.).
  • Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
    Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).×
  • Some of the results of this study were previously reported as an abstract at the Smart Meeting Anesthesia Resuscitation Intensive Care, May 9–11, 2018, in Milan, Italy, and at the European Society of Intensive Care Medicine Lives Congress 2018, October 20–24, 2018, in Paris, France.
    Some of the results of this study were previously reported as an abstract at the Smart Meeting Anesthesia Resuscitation Intensive Care, May 9–11, 2018, in Milan, Italy, and at the European Society of Intensive Care Medicine Lives Congress 2018, October 20–24, 2018, in Paris, France.×
  • Submitted for publication August 17, 2019. Accepted for publication March 26, 2020. Published online first on April 22, 2020.
    Submitted for publication August 17, 2019. Accepted for publication March 26, 2020. Published online first on April 22, 2020.×
  • Address correspondence to Dr. Cammarota: Department of Anesthesiology and Intensive Care, “Maggiore della Carità” University Hospital, Novara Corso Mazzini 18, 28100, Novara, Italy. gmcamma@gmail.com. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Article Information
Critical Care Medicine / Clinical Science / Critical Care / Gastrointestinal and Hepatic Systems / Respiratory System
Critical Care Medicine   |   July 2020
Mechanical Ventilation Guided by Uncalibrated Esophageal Pressure May Be Potentially Harmful
Anesthesiology 7 2020, Vol.133, 145-153. doi:https://doi.org/10.1097/ALN.0000000000003327
Anesthesiology 7 2020, Vol.133, 145-153. doi:https://doi.org/10.1097/ALN.0000000000003327
Abstract

Background: Esophageal balloon calibration was proposed in acute respiratory failure patients to improve esophageal pressure assessment. In a clinical setting characterized by a high variability of abdominal load and intrathoracic pressure (i.e., pelvic robotic surgery), the authors hypothesized that esophageal balloon calibration could improve esophageal pressure measurements. Accordingly, the authors assessed the impact of esophageal balloon calibration compared to conventional uncalibrated approach during pelvic robotic surgery.

Methods: In 30 adult patients, scheduled for elective pelvic robotic surgery, calibrated end-expiratory and end-inspiratory esophageal pressure, and the associated respiratory variations were obtained at baseline, after pneumoperitoneum–Trendelenburg application, and with positive end-expiratory pressure (PEEP) administration and compared to uncalibrated values measured at 4-ml filling volume, as per manufacturer recommendation. Data are expressed as median and [25th, 75th percentile].

Results: Ninety calibrations were successfully performed. Chest wall elastance worsened with pneumoperitoneum–Trendelenburg and PEEP (19.0 [15.5, 24.6] and 16.7 [11.4, 21.7] cm H2O/l) compared to baseline (8.8 [6.3, 9.8] cm H2O/l; P < 0.0001 for both comparisons). End-expiratory and end-inspiratory calibrated esophageal pressure progressively increased from baseline (3.7 [2.2, 6.0] and 7.7 [5.9, 10.2] cm H2O) to pneumoperitoneum–Trendelenburg (6.2 [3.8, 10.2] and 16.1 [13.1, 20.6] cm H2O; P = 0.014 and P < 0.001) and PEEP (8.8 [7.7, 15.6] and 18.9 [16.3, 22.0] cm H2O; P < 0.0001 vs. baseline for both comparison; P < 0.001 and P = 0.002 vs. pneumoperitoneum–Trendelenburg) and, at each study step, they were persistently lower than uncalibrated esophageal pressure (P < 0.0001 for all comparisons). Overall, difference among uncalibrated and calibrated esophageal pressure was 5.1 [3.8, 8.4] cm H2O at end-expiration and 3.8 [3.0, 6.3] cm H2O at end-inspiration. Uncalibrated esophageal pressure swing was always lower than calibrated one (P < 0.0001 for all comparisons) with a difference of −1.0 [−1.8, −0.4] cm H2O.

Conclusions: In a clinical setting with variable chest wall mechanics, uncalibrated measurements substantially overestimated absolute values and underestimated respiratory variations of esophageal pressure. Calibration could substantially improve mechanical ventilation guided by esophageal pressure.

Editor’s Perspective:

What We Already Know about This Topic:

  • Esophageal pressure can be used as a surrogate for pleural pressure for optimizing mechanical ventilation

  • However, surgeries such as pelvic robotic surgery involve fluctuations in abdominal load and intrathoracic pressure that may artificially influence esophageal pressure

What This Article Tells Us That Is New:

  • This study enrolled patients undergoing pelvic robotic surgery and found that esophageal balloon calibration significantly improved assessment of esophageal pressure when compared with the conventional uncalibrated approach to measuring esophageal pressure