Prone Ventilation: Prone ventilation for ARDS is strongly recommended in current clinical practice 9 guidelines and should be implemented early in COVID-19 patients. Current indications for prone ventilation are a persistent hypoxemia defined as P:F < 150 for 12 hours (some clinicians favor < 200 and sooner initiation of prone positioning) after optimal PEEP titration as noted above. Prone ventilation results in a host of improvements to lung mechanics and should be instituted via the MGH prone positioning guideline posted on Apollo. Prone ventilation can be carried out in the patient’s current bed and requires minimal additional equipment. Absolute contraindications to prone ventilation include an inability to turn neck (e.g. fixed or unstable c-spine) and sternal instability. Vascular access lines, chest tubes, and CVVH lines are not contraindications to prone ventilation. Extreme hemodynamic instability is a relative contraindication although consideration should also be given to the possibility that hemodynamics may improve with resolution of hypoxemia. The proning procedure itself should be carried out with staff adhering to current infection control guidance on PPE as outlined in the separate infection control protocols. A bolus of paralytic agent should be given prior to proning (similar consideration apply to the return to supine position). There is no need for ongoing neuromuscular blockade after the proning procedure itself, except as necessitated by vent asynchrony. The patient should be maintained in the prone position until at least the morning after proning. Thereafter, that patient may be assessed for suitability to return to supine position once each morning (qAM). PEEP requirements frequently decrease in the prone position and consideration should be given to decreasing PEEP after proning and increasing PEEP prior to return to the supine position in order to prevent de-recruitment. In particular, ½ of the difference in PEEP between the supine and prone position may be added back prior to return to the supine position (for example, if PEEP is 8 in the prone position , but was 12 in the supine position, then consider increasing PEEP to 10 prior to return to supine condition). If P:F remains greater than 150 (some clinicians prefer 200) and driving pressure is less than 15 at the end of the 2 hour period of supine ventilation on PEEP of 10 cmH2O or less, prone ventilation may be discontinued.