Page 676 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 54: Acute-on-Chronic Respiratory Failure 495

ventilation (16.6 ± 11.8 days and 10.2 ± 6.8 days; p = 0.021) ICU days For many patients, liberation from prolonged mechanical ventilation
(24.0 ± 13.7 days and 15.1 ± 5.4 days; p = 0.005), incidence of is associated with a decision to change the goals of care from treatment-
nosocomial pneumonia, and mortality at 60 days (8% NIV vs 28% for-cure to treatment-for-comfort. Decisions to withhold and withdraw
invasive ventilation; p = 0.009), while increasing approximately four- life-sustaining therapy entail extensive involvement of the patient, their
fold the number of patients liberated from ventilation at day 21. In care providers, ICU staff, chaplaincy, hospital ethics, and social work
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a meta-analysis of 12 studies, 530 predominantly COPD patients were support. Pertinent to the terminal care of the ACRF patient, are meticu-
generally randomized to one of the two strategies after failing only a lous attention to palliation of terminal dyspnea, pain, and delirium. This
single SBT. Extubation to NIV translated into an aggregate 45% rela- subject is covered in Chap. 18.
tive risk reduction for mortality (95% CI 21%-62%) at 30 to 90 days.
214
Secondary outcomes were consistent in magnitude and direction with QUALITY PERFORMANCE MEASUREMENT
significant reductions in VAP (RR 0.29, 95% CI 0.19-0.45), ICU length AND REPORTING FOR ACRF
https://kat.cr/user/tahir99/
of stay (weighted mean difference [WMD] −6.27 days, 95% CI −8.77
to −3.78) and total duration of ventilation (WMD) −5.64 days (95% Efforts to improve the consistency and quality of care delivery for
CI −9.50 to −1.77). Extubation had no effect on failures to liberate or critically ill patients while containing costs has become a major focus
duration of ventilation related to efforts to liberate. NIV is likely to internationally. Process, structure, and outcomes measures for ACRF
214
tide the patient over the additional days until the balance of neuromus- have been developed and in some countries are used for public report-
cular competence and respiratory system load is reestablished and we ing of hospital care and value-based purchasing. As an example, the
routinely apply this approach in appropriate patients. UK National Institute for Health and Clinical Excellence (NICE) has
Even with appropriate institution of rest on the ventilator, rapid defined and implemented a process-of-care measure for NIV, which
application of the algorithms given above or correction of abnor- is used for benchmarking, performance improvement, and remu-
malities of neuromuscular competence and load, and progressive neration decisions 90,220 (Table 54-4). It is likely that composite process
exercise of the patient, some patients fail efforts to liberate and require measures (care bundles) for ACRF management will become more
protracted periods of ventilator support. Indeed, with the wider use widely used.
of NIV and the avoidance of intubation in all but the most severely
impaired patients, it may be the case that in the future, ICUs will
encounter truly “difficult to wean” patients. The principles elaborated
above still apply to this group, with a few additional comments. After
approximately 7 days of ventilator dependence, we typically assess the TABLE 54-4 Quality Standard: Noninvasive Ventilation in Hospital (UK National
patient for tracheostomy (see Chap. 46). If it appears that liberation Institute for Health and Clinical Excellence, NICE) 89,219
215
from mechanical ventilation may succeed within another week, tra- Quality statement
cheostomy is usually not performed, and efforts continue to extubate People admitted to hospital with an exacerbation of COPD and with persistent acidotic
the patient. If we judge that the course will be protracted, we perform ventilatory failure are promptly assessed for, and receive, noninvasive ventilation delivered
bedside, percutaneous tracheostomy for purposes of patient comfort, by appropriately trained staff in a dedicated setting.
communication, and avoidance of complications associated with
translaryngeal intubation. Quality measure
If progress to liberation is likely to be very slow after the first couple Structure
of weeks, many ICUs will consider transferring the stable patient to a a. Evidence of local arrangements for the prompt assessment and delivery of noninvasive
long-term acute care facility with dedicated expertise in pulmonary ventilation (NIV) to people admitted to hospital with an exacerbation of COPD and
rehabilitation and liberation from mechanical ventilation. Despite persistent acidotic ventilatory failure.
the overall poor prognosis of patients with nonresolving respiratory b. Evidence of local arrangements to ensure that people admitted to hospital and receiv-
failure who are discharged to a LTAC, these facilities have dem- ing NIV for an exacerbation of COPD and persistent acidotic ventilatory failure, have NIV
216
onstrated a superior expertise in liberating a significant proportion delivered by appropriately trained staff in a dedicated setting.
even after long periods of ventilation for ACRF. Optimal results are
217
achieved when a protocolized multidisciplinary care pathway involves Process
specialist respiratory care, rehabilitation, nutrition, and physical a. Proportion of people admitted to hospital with an exacerbation of COPD and with
therapy departments. persistent acidotic ventilatory failure, who are promptly assessed for NIV, and for whom
Following extubation, careful serial assessments are in order. any subsequent delivery is promptly undertaken
Deterioration in the hours just following extubation suggests upper Numerator—the number of people in the denominator promptly assessed for NIV, and
airway edema. In the uncomplicated patient, the respiratory rate falls for whom any subsequent delivery is promptly undertaken
slightly through the first day, most often into the mid-20s to low 30s. An Denominator—the number of people admitted to hospital with an exacerbation of
airway occlusion pressure of >3.3 cm H O at 0.1 second (P0.1) recorded COPD and persistent acidotic ventilatory failure
2
1 hour after extubation has been proposed as a highly specific method b. Proportion of people admitted to hospital and receiving NIV for an exacerbation of
for identifying ACRF patients likely to fail and require reintubation, COPD and persistent acidotic ventilatory failure, who have it delivered by appropriately
218
however this has not been validated in patients electively extubated to trained staff in a dedicated setting
NIV. Efforts to build strength and reduce load should continue in order Numerator—the number of people in the denominator having NIV delivered by appro-
to protect the gains that have been made. Once the patient is stable off priately trained staff in a dedicated setting
of the ventilator, a prompt transfer to a progressive care unit or general Denominator—the number of people admitted to hospital receiving NIV for an exacer-
ward should be encouraged. bation of COPD and persistent acidotic ventilatory failure
Recurrence of respiratory failure is an ominous but not infrequent Outcome
complication for which efforts to stave off intubation may prove fruitless
and potentially harmful. When 221 patients with recurrent respiratory a. Reduction in hospital mortality rate of patients admitted with an exacerbation of COPD
failure within 48 hours of initial ventilator liberation (only 12% had b. Reduction in median length of stay of patients admitted with an exacerbation of COPD
COPD) were randomized to either NIV or usual care, equal numbers c. Reduction in complications, specifically ventilator-associated pneumonia
progressed to intubation (48%) but the ICU mortality rate at an interim d. Reduction in the need for intubation
analysis was 25 percent in the NIV versus 14 percent in the usual care This quality statement is taken from the COPD quality standard.
arm (relative risk 1.78; 95 % CI 1.03-3.20; p = 0.048). 219 Data from 2012 National Institute for Health and Clinical Excellence.

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