2004 OPEN FORUM Abstracts
INITIAL RESULTS: FLEXIBLE PROTOCOL FOR ALI/ARDS INCORPORATING ARDSNET-TYPE PROTECTIVE STRATEGIES.
John W. Farnham, RRT; Michael S.
Powers, MS, RRT. Respiratory Care Services, University of Tennessee
Medical Center, 1924 Alcoa Highway, Knoxville, TN 37920.
Background:Use of low tidal volume (VT) and low plateau pressure
(Pplat) as strategies for improving outcomes in patients
suffering from Acute Lung Injury (ALI) or Acute Respiratory Distress
Syndrome (ARDS) has been shown to improve outcomes by the ARDS
Network study and numerous subsequent studies. Different critical
care clinicians have different preferred ways to manage these
difficult patients during ventilatory support. Based on our successes
with therapist driven protocols (TDP) for respiratory treatments and
for ventilator management and liberation, we were asked to develop a
protocol that would provide a systematic approach to management of
ALI/ARDS, yet would allow the physicians flexibility in their choices
of approach. The protocol was to maintain, in all options, the basic
underlying ARDS Net philosophy of low VT and low Pplat.
Method: An interdisciplinary team was formed to shepherd the
development of the protocol. Membership included respiratory
therapists, physicians who would be managing this cohort of patients,
and a nurse representing the affected division of nursing so we would
not lose touch with the necessary disciplines as we moved forward.
We developed a protocol that included a verbatim ARDSNet option,
a pressure control (PC) option, and an airway pressure release option
(APRV). While we fine tuned the protocol options to meet the
physicians’ needs, we retrospectively looked at the previous
year’s ALI/ARDS cases to determine outcomes of those cases. In
application, the attending physician decides to enter the protocol,
and decides which option to use. If deemed appropriate, the physician
can change freely between the 3 options as is felt best for the
patient. We developed a collection of data points we would use to
monitor the process, and began using the protocol in May, 2004 in all
adult critical care areas.
Results: For the year prior to
beginning use of the protocol our mortality rate had been 50.4%. As
of the date of the writing of this abstract, the overall mortality
rate since implementing the protocol is 39.3% in 33 patients, an
improvement of 11.1% in almost two months. On 3 occasions, nitric
oxide was used, 1 of those patients survived. One patient was proned,
and did not survive. On 12 occasions, PC mode was used, on 22
occasions ARDSNet, and on 1 occasion, APRV. Three patients were
treated using more than one strategy. Of those who died, 8 had been
on ARDSNet, 3 on PC, and 2 on multiple modes.
Conclusions: Clear
improvement in survival has been demonstrated in a short period of
time. The study cohort is too small to draw definitive conclusions of
other aspects at this point. However, the set of data has great
potential for interest to the community in that survival of different
strategies can be compared, all being linked by having low VT
and low Pplat in common. Not comparing differing
applications is considered to be one weakness of the ARDSNet study.
As time goes on and the total “N” of this study grows,
more significant data on the various aspects being monitored will be
available for evaluation. Further, as the skill with which this
protocol is applied improves, it is reasonable to expect further
improvement in mortality outcomes. The possibility of comparing, over
time, whether or not ARDSNet ventilation truly is superior to other
modes, so long as low VT and low Pplat are
utilized, is a tremendous opportunity afforded with this study. Other
details not elicited by the ARDSNet study may also be elicited.
Preliminary results are quite promising, and long term follow up is
indicated and planned.