Effects of prone and lateral position in non-intubated patients with 2019 Novel Coronavirus (COVID-19) pneumonia

Abstract

Effects of prone and lateral position in non-intubated patients with 2019 Novel Coronavirus (COVID-19) pneumoniaTo the Editor: Mechanical ventilation in the prone position is a validated strategy of invasive ventilator support in the treatment of acute respiratory distress syndrome (ARDS). 1 Given its beneficial effects, there has been some research into the use of prone positioning also in non-intubated patients with ARDS 2,3 and in patients with COVID-19 to avoid intubation, 4,5 but few studies 2,3,6,7 have assessed its efficacy and possible effects during SARS Cov-2 pandemic.8---13 The use of standard oxygen and High Flow Nasal Cannula (HFNC) in refractory hypoxemia due to SARS CoV-2 is controversial and many International Guidelines, while suggesting a brief trial, raise concerns about the potential risk of unduly delayed intubation.We describe the physiological changes and clinical outcome of three patients suffering from severe Acute Respiratory Failure (ARF) due to COVID-19 undergoing trials using semi-recumbent, prone and lateral position during standard oxygen and HFNC.All patients tested positive on reverse transcription-polymerase chain reaction (RT-PCR) on throat swabs; comorbidities and administered drugs are reported in Table 1.A 74 year-old woman was admitted on March 19th, after 10 days of fever.On the 24th she was transferred to our Respiratory Intensive Care Unit (RICU) due to worsening of her respiratory conditions.On arrival, she was haemodynamically stable, her respiratory rate was 18/min in a reservoir oxygen mask at 15 l/min; ABG testing showed a severe impairment of gas exchange (PaO2/FiO2 87; PaO2 69 mmHg, PaCO2 33 mmHg, pH 7.49, HCO3-27,8 mmol/L).We initiated non-invasive ventilation (NIV) with helmet interface (PSV: PS 22 cmH2O, PEEP 10 cmH2O, FiO2 80%), without improvement of gas exchange (PaO2/FiO2 80).A high resolution CT-scan (HRCT) showed bilateral consolidations with groundglass opacities (GGO), mainly in the posterior dependent zones.Based on this radiological picture we pronated the patient whilst administering oxygen-therapy with reservoir mask.An almost immediate increase of SpO2 was observed (Fig. 1).At 2 h the PaO2/FiO2 had increased to 203 mmHg and this trend was maintained after 12 h of prone positioning (Table 1).She improved slowly with a schedule of pronation of two sessions lasting 6 h throughout the day and overnight and was discharged home on April 29th.The second case was a 71-year-old man, admitted to the Emergency Department (ED) with fever and progressively worsening dry cough for one week.On admission, ABG showed ARF (PaO2/FiO2 261, PaO2 55 mmHg, PaCO2 31 mmHg, pH 7.45, HCO3-24 mmol/l).Clinical conditions and gas exchange rapidly worsened (ABG 48 h after admission: PaO2/FiO2 186, PaO2 65 mmHg, PaCO2 33 mmHg, pH 7.43, HCO3-25,6 mmol/L) and on day 6 since admission he was referred to our RICU, where HFNC therapy was set (Flow 50 L/min, FiO2 50%).The HRCT scan showed parenchymal involvement of the left lung, with relative sparing of the right one.A spontaneous breathing trial was performed placing the patient on the right lateral decubitus during HFNC