A case of shunting postoperative patent foramen ovale under mechanical ventilation controlled by different ventilator settings

  • Claudio Pragliola | claudio.pragliola@libero.it The Heart Centre, King Faisal Specialist Hospital and Research Centre, Ryadh, Saudi Arabia. http://orcid.org/0000-0001-7011-6461
  • Sara Di Michele Department of Cardiovascular, Respiratory, Nephrological, Anaesthetic and Geriatric Sciences, La Sapienza University, Roma, Italy.
  • Domenico Galzerano The Heart Centre, King Faisal Specialist Hospital and Research Centre, Ryadh, Saudi Arabia.

Abstract

A 56-year old male with ischemic heart disease and an unremarkable preoperative echocardiogram underwent surgical coronary revascularization. An intraoperative post pump trans-esophageal echocardiogram (TOE) performed while the patient was being ventilated at a positive end expiratory pressure (PEEP) of 8 cm H2O demonstrated a right to left interatrial shunt across a patent foramen ovale (PFO). Whereas oxygen saturation was normal, a reduction of the PEEP to 3 cm H2O led to the complete resolution of the shunt with no change in arterial blood gases. Attempts to increase the PEEP level above 3 mmHg resulted in recurrence of the interatrial shunt. The remaining of the TEE was unremarkable. Mechanical ventilation, particularly with PEEP, causes an increase in intrathoracic pressure. The resulting rise in right atrial pressure, mostly during inspiration, may unveil and pop open an unrecognized PFO, thus provoking a right to left shunt across a seemingly intact interatrial septum. This phenomenon increases the risk of paradoxical embolism and can lead to hypoxemia. The immediate management would be to adjust the ventilatory settings to a lower PEEP level. A routine search for a PFO should be performed in ventilated patients who undergo a TEE.

Downloads

Download data is not yet available.

Author Biographies

Claudio Pragliola, The Heart Centre, King Faisal Specialist Hospital and Research Centre, Ryadh
Heart Centre
Domenico Galzerano, The Heart Centre, King Faisal Specialist Hospital and Research Centre, Ryadh
Heart Centre
Published
2017-08-04
Section
Case Reports
Keywords:
Mechanical ventilation, patent foramen ovale, positive end expiratory pressure, transesophageal echocardiography.
Statistics
Abstract views: 478

PDF: 370
HTML: 115
Share it

PlumX Metrics

PlumX Metrics provide insights into the ways people interact with individual pieces of research output (articles, conference proceedings, book chapters, and many more) in the online environment. Examples include, when research is mentioned in the news or is tweeted about. Collectively known as PlumX Metrics, these metrics are divided into five categories to help make sense of the huge amounts of data involved and to enable analysis by comparing like with like.

How to Cite
Pragliola, C., Di Michele, S., & Galzerano, D. (2017). A case of shunting postoperative patent foramen ovale under mechanical ventilation controlled by different ventilator settings. Clinics and Practice, 7(3). https://doi.org/10.4081/cp.2017.969