In some intensive care, nowadays, ultrasound diagnostics have become an extension of the physical examination (like a stethoscope) [
1]. In the clinical practice of our intensive care unit (ICU), we perform a whole echocardiography every morning (echo-round) and every time a patient is admitted. Clinical studies have shown that diagnostic ultrasound can be superior to the physical exam alone [
2,
3]. One of the most successful approaches in the field of acute respiratory failure is the ‘BLUE Protocol’ [
4], but it does not address the issue of diaphragm dysfunction (DD). It may be due to several causes such as trauma, surgery, myopathy, neuropathy, mediastinal masses, mechanical ventilation, and diseases that cause lung hyperinflation and also to metabolic, infective, or inflammatory disorders. These alterations may affect only one or both hemi-diaphragms and may present with different intensities, ranging from only a partial loss of the ability to generate negative pressures (weakness) to a complete loss of diaphragmatic function (paralysis) [
5]. In the setting of liver transplantation (OLTx), right diaphragmatic dysfunction is an occurrence often overlooked but actually quite common in the immediate postoperative period: McAllister [
6] found that 79% of liver recipients had right phrenic nerve injury and approximately half of these patients also had hemidiaphragm paralysis. Patients with unilateral diaphragmatic paralysis are usually asymptomatic, and phrenic nerve conduction generally tends to recover within a few months [
7]. Most of these patients are able to maintain adequate ventilation and gas exchange both at rest and during mild exercise, probably through compensatory mechanisms such as an increase in the work of the normal hemidiaphragm and of the intercostal muscles [
8]. The combination of anesthesia and surgical insult can induce changes in respiratory mechanics on their own, such as hypoxemia, reduced lung volume, and atelectasis, then leading to a restrictive syndrome. If in this context you put a diaphragmatic dysfunction too, respiratory function may be so impaired as to lead to respiratory failure after discontinuation of mechanical ventilation [
9].