Each day a patient spends on a ventilator increases pneumonia risk by about 1% (Am J Respir Crit Care Med. 2002;165:867-903). Being unable to move or talk also might induce a sense of helplessness. As a result, many clinicians wean off a ventilator sooner rather than later.
A recent study (JAMA. 2013;309:671-677) has found that unassisted breathing via a tracheostomy collar facilitates a quicker transition than breathing with pressure support after prolonged mechanical ventilation (>21 days). Investigators reported their findings at the Society of Critical Care Medicine’s 42nd Congress in January in San Juan, Puerto Rico.
On average, patients were able to successfully wean four days earlier with unassisted breathing versus pressure support—a significant difference, says lead investigator Amal Jubran, MD, section chief of pulmonary and critical-care medicine at the Edward Hines Jr. VA Hospital in Chicago. No major differences were reported in survival between the two groups at six-month and 12-month intervals after enrollment in the study.
“The faster pace of weaning in the tracheostomy collar group may be related to its effect on clinical decision-making,” says Dr. Jubran, a professor at Loyola University Chicago’s Stritch School of Medicine. “Observing a patient breathing through a tracheostomy collar provides the clinician with a clear view of the patient’s respiratory capabilities.”
In contrast, with pressure support, a clinician’s perception of weanability “is clouded because the patient is receiving ventilator assistance,” she says. “It is extremely difficult to distinguish between how much work the patient is doing and how much work the ventilator is doing.”
Amid this uncertainty, Dr. Jubran adds, clinicians are more likely to accelerate the weaning process in patients who unexpectedly respond well during a tracheostomy collar challenge than in those receiving a low level of pressure support.
In the study, less than 10% of 312 patients—most of whom were elderly—required reconnection to a ventilator after being weaned successfully. Weaning efforts should be restarted only after cardiopulmonary stability has been reached, she says.
Factoring into the equation are the measurements for blood pressure and respiratory rate and the amounts of oxygenation and sedation in patients on ventilators, says Paul Odenbach, MD, SHM, a hospitalist at Abbott Northwestern Hospital in Minneapolis.
“I look at them clinically overall,” he says. “The most important piece is eyeballing them from where they are in their disease trajectory.
Are they awake enough to be protecting their airway once they are extubated?” he adds. He has found that a stable airway is more easily achieved with a tracheostomy collar.
Listen to Dr. Odenbach explain what hospitalists should watch out for when weaning patients off mechanical ventilation, especially in critical-care situations.
Managing heart failure, treating infections, and optimizing nutrition are crucial before weaning off ventilation, says geriatrician Joel Sender, MD, section chief of pulmonary medicine at St. Barnabas Hospital in Bronx, N.Y., and medical director of its Rehabilitation & Continuing Care Center.
“It is important to identify the best candidates for weaning and then apply the best methods,” says Dr. Sender. “Sadly, many patients are not good candidates, and only a portion are successfully weaned.” That’s why “there’s a great need to have a frank discussion with the family to answer their questions and to promote a realistic set of treatment goals.” TH
Susan Kreimer is a freelance writer in New York.
Key Takeaways for Hospitalists
- The biggest obstacle in weaning management is the delay in starting to assess whether a patient is ready for weaning.
- Weaning off mechanical ventilation should be attempted as soon as cardiopulmonary instability has been resolved.
- Patients requiring prolonged mechanical ventilation should be weaned with daily trials of unassisted breathing through a tracheostomy collar and not with pressure support.