|
NPPV IN PATIENTS WITH ORDERS NOT TO INTUBATE
|
Key Points
|
• Overall mortality is high among patients with acute respiratory failure and do-not-intubate orders when these patients receive NPPV.
• The likelihood of survival to discharge is greater among patients who have a higher baseline Paco2, a diagnosis of congestive heart failure, and the ability to cough, and in those who are awake. |
PROVIDENCE, RHODE ISLAND—The use of noninvasive positive-pressure ventilation (NPPV) in terminally ill patients who do not want to be intubated and mechanically ventilated is currently controversial. Some caregivers consider this practice inappropriate, arguing that it is essentially giving life support to patients who do not want it. Others insist that NPPV is helpful for dying patients who have rejected intubation, because it can alleviate respiratory distress and give the patients time to put their affairs in order.
Helping patients and their loved ones decide this issue for themselves will require that they have access to information on the outcomes of NPPV in the terminally ill—a subject that has seldom been studied. Thus, Mitchell M. Levy, MD, and colleagues prospectively evaluated outcomes with the use of NPPV in 114 elderly patients with acute respiratory failure and do-not-intubate orders.1 Dr. Levy is Medical Director of the Medical Intensive Care Unit at Rhode Island Hospital in Providence, Rhode Island.
The main findings of the study: Overall, 43% of the patients survived to discharge. However, several variables—higher baseline Paco2, a diagnosis of congestive heart failure or COPD, being awake, and having the ability to cough—were associated with significantly increased odds of survival.
SURVIVAL RATES AND PREDICTORS
COPD was the most frequent diagnosis in the study population, and was followed by congestive heart failure and pneumonia. The patients received NPPV for dyspnea, signs of respiratory distress, increased accessory muscle use, abdominal paradox, and abnormal blood gases.
Using an oronasal mask in 111 cases and a nasal mask in three, caregivers started the patients on NPPV at mean inspiratory and expiratory pressures of 13.0 and 5.3 cm H2O, respectively. The average duration of NPPV therapy was 13.2 hours, although it ranged from 10 minutes to 12 days.
Although the overall rate of survival to discharge was low, that rate was about 75% for patients with congestive heart failure and just over 50% for those with COPD. It was 58% for patients with a baseline Paco2 of 80 mm Hg or higher, versus 32% for those with a lower baseline Paco2. By contrast, survival to discharge among those with pneumonia, cancer, or other diagnoses was only about 20% to 25%.
According to a multivariate analysis, being awake, having the ability to cough, a baseline Paco2 of 80 mm Hg or higher, a diagnosis of congestive heart failure, and a diagnosis of COPD were all associated with reduced odds ratios (ORs) for hospital mortality of 0.18, 0.16, 0.01, 0.14, and 0.31, respectively. However, patients without these conditions did not fare so well. Respective increases in the ORs for hospital mortality of 1.98, 1.58, and 14.2 were observed for patients who had cancer, pneumonia, and other diagnoses.
Interestingly, simple bedside assessments that were made by respiratory therapists of a patient’s ability to cough and whether or not a patient was awake also predicted survival to hospital discharge. Age, gender, care in a community versus a teaching hospital, and baseline pH and Pao2 did not influence survival.
WHAT DO PATIENTS WANT?
“Our findings underscore the importance of advance planning conversations with terminally ill patients and their families and finding out exactly what patients want,” Dr. Levy told Pulmonary Reviews. “When patients say they do not want to be intubated, they may simply mean that they do not wish to be subjected to the discomfort of a mechanical ventilator but might be willing to receive NPPV. Or they may mean they do not want any intervention and are prepared to die. How do you know unless you ask?”
—Timothy Begany
Reference
1. Levy M, Tanios MA, Nelson D, et al. Outcomes of patients with do-not-intubate orders treated with noninvasive ventilation. Crit Care Med. 2004;32:2002-2007.
Return
to table of contents
|
|
