Mechanical Ventilation is an essential life-saving therapy for more than 300,000 US patients each year. However, there is not a universally agreed upon definition of prolonged mechanical ventilation (PMV) and timing for transfer of patients to long-term acute care (LTAC). Additionally, evidence in this area has been contradictory and outdated.

In reviewing the InterQual^® criteria for this issue, we recognized the need to dig deeper to define the ideal best practice. To do that, we conducted an in-depth literature review and reached out to the authors of a key study to clarify our understanding of the findings. These discussions led to a follow-up panel discussion with the two authors of a vent weaning study, John Votto, DO, FCCP, a practicing pulmonologist and chief medical officer for the NALTH and Lane Koenig, PhD, a healthcare economist and director of policy and research for the NALTH. I wanted to share the valuable insights from the conversation with these experts in the field.

The clinical perspective

The existing guidance was defined by a consensus paper published more than 15 years ago and it defined PMV acceptable timing to transfer to LTAC as six hours a day for 21 days.  From the clinical perspective, Dr. Votto shared that he thinks the definition was “fairly arbitrary” and although it may have been reasonable 15 years ago, medicine has changed and research, which we will touch upon later, has found a correlation between early transfer, when clinically appropriate, and improved outcomes.

In discussing how to identify patients who will require PMV and who may benefit for a weaning program in a LTAC, Dr. Votto mentioned that from his experience, some patients who are likely to need prolonged mechanical ventilation are fairly easy to identify such as those with progressive neuromuscular diseases, very high spinal cord injuries and multiple traumas. For other conditions, additional factors needed to be considered when determining whether a patient will require PMV and their likeliness to wean include: age; frailty; BMI; nutritional status; conditions such as: Severe COPD, Congestive heart failure, and Chronic renal failure; patients with a left ventricular ejections fraction of less than 25%; number of organ system failures, mental status, and the time of original trauma.  It comes as no surprise that the more clinically complex, the harder it may be to wean.

In addition to patient complexity, a notable challenge faced by LTAC providers is the length of time the patient is in the acute setting before being transferred. The longer the patient is in the acute setting, specifically the ICU, the higher the likelihood that they are going to be nutritionally compromised and experience muscle atrophy and therefore harder to wean.

Uncertainty with timing of transfer impacts outcomes

The challenge of who should be transferred to LTACs and when was covered in a recent research article published in BMC Pulmonary Medicine co-authored by Lane Koenig. This peer-reviewed study assesses the relationship between length of stay in a short-term acute care hospital after endotracheal intubation (time to LTAC) and weaning success and mortality for ventilated patients discharged to an LTAC. Findings suggest that delaying ventilated patients' discharge to LTAC may negatively influence the patients' chances of being weaned from the ventilator.

In further discussing this, Dr. Koenig highlighted that not only are there improved patient outcomes, but from an economic perspective, this means lower costs for short term acute hospitals and increased ICU bed availability – a win for all involved.

The future: use COVID research to adapt

One of the areas we talked about was where we go from here and what the future holds. Their insights revealed more research is needed and the value that COVID data will have.

Although, LTACs were set up for the needs of COVID patients, during the pandemic isolation rooms became a problem.  From his experience, Dr. Votto shared that hospitals should take the learning from the pandemic and adapt for the future. For example, organizations should look at cohorting patients that have infectious diseases on units or move to an assigned “pods” model, where for example you can have a pod for CHF and a pod for the  COVID patient and a pod for ventilatory weaning that is not for COVID.

As we all know the pandemic created unprecedented capacity issues and as a result transitions of care may have occurred a bit earlier than pre-pandemic. From a healthcare economists’ standpoint, Dr. Koenig is excited to see what the data shows regarding those patients and their outcomes. Furthermore, we should look closer at the differences in treatment patterns between fee for service beneficiaries and Medicare advantage beneficiaries who are on PMV. We know that patients in Medicare advantage tend to stay longer in the short-term acute care hospital versus fee for service. There is not a lot of research that compares different treatment approaches across payment systems.

There is more research needed in this area. We used the best evidence available today to modify the criteria better reflecting the expected time to stabilization necessary for LTAC transfer (14 days), whether or not a tracheostomy is placed, and addressing exceptions (tracheostomy placement and stabilization prior to 14 days is unlikely, however we recognize that it does occur and have included additional non-time-based criteria to support those cases). We look forward to the research to come and to continue to update guidance based on the latest findings.