Zero Degree Head Positioning in Hyperacute Large Artery Ischemic Stroke

Positioning of the patient during hyperacute ischemic stroke (AIS) treatment is an important,
yet understudied aspect of nursing care that could impact the course of treatment and
clinical outcome. Since 1968, clinical symptom worsening in AIS patients has been documented
with the head of bed (HOB) elevated to 30 degrees or higher, while clinical improvement or
symptom stability has been noted with zero degree HOB positioning. Mechanisms for zero degree
HOB clinical improvement include favorable gravitational blood flow conditions and
recruitment of collateral blood channels, while in the case of treatment with clot-busting
medications, increased blood flow may allow more medication to reach occluded arteries
facilitating clot breakdown. Despite this, there is currently divide within the clinical
community about what position is best for patients, although it has been argued that zero
degree head positioning should be among the first steps taken to improve blood flow to the
brain and prevent stroke symptom worsening. The investigators have shown that elevated ICP is
absent in early AIS, and that pneumonia is rare using these piloted methods. However, no
large clinical trial has examined efficacy and safety of zero degree HOB positioning within
hyperacute large vessel occlusion (LVO) ischemic stroke patients with potentially viable
brain tissue, leaving the acute stroke community confused as to what constitutes best
practice. ZODIAC is a prospective randomized open blinded endpoint (PROBE) clinical trial of
head positioning to determine if zero degree HOB positioning during the early phase of
hyperacute LVO ischemic stroke management prevents neurological symptom worsening. Mechanical
thrombectomy (MT) eligible patients (n=182) will be randomized to one of two groups: 1) Zero
degree HOB positioning; or, 2) thirty degree HOB positioning. The hypothesis is that optimal
HOB position can be determined by early neurological symptom worsening during the
intervention (Aim 1) prior to initiation of the thrombectomy procedure, and the investigators
propose that real-time deterioration may be a surrogate measure for decreased downstream
perfusion, potentially impacting viability of brain at risk for infarction. Aim 2 will
confirm that use of zero degree HOB positioning for AIS is safe. Use of this nursing measure
holds significant promise as an innovative adjunct method to improve AIS symptoms, and
ultimately reduce disability.

Inclusion Criteria:

- Ischemic stroke symptoms consistent with large artery occlusion

- Baseline standard of care non-contrast head CT (or MRI) negative for hemorrhage or
mass-effect

- Evidence of arterial occlusion on standard of care CT angiography or MR angiography

- Favorable neuroimaging (Alberta Stroke Program Early Computed Tomography Score
[ASPECTS] > 6 in anterior circulation stroke; not applicable in posterior circulation
stroke)

- Ordered treatment with mechanical thrombectomy

- Pre-stroke baseline modified Rankin Score (mRS) < 1

- Ability to enroll, randomize and begin the intervention within the Emergency
Department

Exclusion Criteria:

- Non-English speaking subjects will be excluded due to use of English language
instruments (modified Rankin Scale [mRS] & NIHSS) and English speaking investigators

- Pregnancy or suspicion of pregnancy

- Evidence or suspicion of vomiting any time prior to consent which could predispose to
aspiration pneumonia and therefore confound determination of protocol safety

- Anticipated palliative care referral

- Evidence of evolving malignant infarction on admission noncontrast CT (or MRI)

- Need for intubation with mechanical ventilation, or non-invasive ventilatory support
with either bi-level positive airway pressure (BiPAP) or continuous positive airway
pressure (CPAP)

- Inability to tolerate zero-degree positioning due to congestive heart failure,
preexisting pneumonia, chronic obstructive pulmonary disease, or other medical
condition

- Admission chest radiograph positive for pleural effusion, pulmonary edema, pneumonia,
or other pulmonary condition that may confound determination of protocol safety

- Abnormal breath sounds on admission assessment that may confound determination of
protocol safety

- Lack of a telephone and/or permanent address predisposing patients to be lost to
follow up

- Enrollment in another clinical trial that may affect our primary or secondary
endpoints

- In the absence of a consenting legal next of kin, any medical, psychological,
cognitive, social or legal condition that would interfere with informed consent and/or
capacity to comply with all study requirements, including the necessary time
commitment