The feasibility of continuous positive airway pressure ventilation in acute ischemic stroke patients: a pilot study

The prevalence of obstructive sleep apnea (OSA) in stroke patients is high and
evidence shows that OSA is negatively correlated to cognitive and functional
recovery in ischemic stroke (IS) patients. Previous studies suggest that
initiation of continuous positive airway pressure (CPAP) gives a greater
improvement in cognitive status and acceleration of neurological recovery in IS
patients diagnosed with OSA. However, currently OSAS in stroke patients is
often left untreated or undiagnosed and to the best of our knowledge, no
studies have been performed analysing the effect of CPAP in, first-ever, acute
IS (AIS) patients in the very acute phase. Although previous studies suggest
the beneficial effect of this treatment in stroke recovery, compliance issues
seem to be greater in AIS patients. This is probably because of the variety of
symptoms related to AIS, such as aphasia and/or a decrease in awareness, which
makes proper verbal instructions difficult. In addition, One could also argue
that masks problems may be greater than in OSA patients, since AIS patients
occasionally suffer from (partial) facial and pharyngeal palsy and as a
consequence might experience fitting problems and leakage of their CPAP mask.
Furthermore, since CPAP treatment in this specific patient group is not part of
regular treatment guidelines this may lead to logistics problems in therapy
support, resulting in low compliance.

The aim of this pilot study is to assess the feasibility of the use of CPAP in
the acute phase of stroke in AIS patients. In other words, we want to evaluate
if the treatment is tolerated and whether it can be applied as scheduled.

We will perform a pilot study with a follow-up period of 3 months per patient.
Ten consecutive patients who give informed consent admitted to the stroke unit
with an AIS will receive CPAP. Patients will receive CPAP within 24 hours after
hospital admission, but at least 3 hours after alteplase infusion, during the
total study period of 3 months during sleep. Patients will be admitted to the
stroke unit for 24 hours and subsequently transferred to the Neurology unit.
During admission, patients and their caregivers (e.g. family, friends) will
receive verbal and written instructions on how to use the device. After
hospital discharge, a specialized nurse will provide therapy support, in
patients* home situation or rehabilitation center, to evaluate therapy
compliance and to determine whether there are any other therapy-related
problems. This consists of a weekly consultation by phone and visit to home or
rehabilitation center if indicated. After 3 months of follow-up a PSG will be
performed in combination with a follow-up visit at the Neurology department. A
wash-out period of one week for CPAP will be applied to prevent the possible
influence CPAP on PSG results.

In 1981, CPAP was introduced for the treatment of patients with OSA. Since
then, CPAP is considered the gold standard treatment in patients with moderate
to severe OSA. CPAP acts as a pneumatic splint, preventing the upper airway
from collapsing. Although, the therapy is hampered by a high level of
non-compliance- 1 out of 3 patients does not tolerate CPAP-, the efficiency
when used is high. Successful treatment is defined when AHI is reduced to less
than 5.

Possible side effects can be related to the interface (skin abrasion from
contact with the mask, claustrophobia, mask leak, irritated eyes), pressure
(nasal congestion and rhinorrhea with dryness or irritation of the nasal and
pharyngeal membranes, sneezing, gastric and bowel distension, recurrent ear and
sinus infections) and negative social factors.

CPAP is generally accepted as a safe and effective treatment of moderate to
severe OSA patients and the risks are limited.