Date Published: February 1, 2018
Publisher: Public Library of Science
Author(s): Yvonne Teuschl, Michaela Trapl, Paulina Ratajczak, Karl Matz, Alexandra Dachenhausen, Michael Brainin, Stefan Kiechl.
While formal screening for dysphagia following acute stroke is strongly recommended, there is little evidence on how multi-consistency screening and dietary modifications affect the rate of stroke-associated pneumonia (SAP). This observational study reports which factors affect formal screening on a stroke-unit and how dietary recommendations relate to SAP.
Analyses from a database including 1394 patients admitted with acute stroke at our stroke-unit in Austria between 2012 and 2014. Dietary modifications were performed following the recommendations from the Gugging Swallowing Screen (GUSS). Patients evaluated with GUSS were compared to the unscreened patients.
Overall, 993 (71.2%) patients were screened with GUSS; of these 50 (5.0%) developed SAP. In the 401 unscreened patients, the SAP rate was similar: 22 (5.5%). Multivariable analysis showed that either mild to very mild strokes or very severe strokes were less likely to undergo formal screening. Older age, pre-existing disability, history of hypertension, atrial fibrillation, stroke severity, cardiological and neurological complications, nasogastric tubes, and intubation were significant markers for SAP. Out of 216 patients, 30 (13.9%) developed SAP in spite of receiving nil per mouth (NPO).
The routine use of GUSS is less often applied in either mild strokes or very severe strokes. While most patients with high risk of SAP were identified by GUSS and assigned to NPO, dietary modifications could not prevent SAP in 1 of 7 cases. Other causes of SAP such as silent aspiration, bacteraemia or central breathing disturbances should be considered.
Pneumonia is a frequent complication after stroke and increases the risk for mortality and dependency [1–2]. Approximately 14% of patients suffer from pneumonia during the first week after stroke, but there is high variability in the reported numbers depending on the population, the study design and the diagnosis criteria . Dysphagia is a major risk factor for stroke-associated pneumonia (SAP) observed in up to 78% of stroke patients, and has been associated with higher mortality, worse functional outcome and longer hospital stay [4–7].
This retrospective database analysis includes all patients (n = 1394) admitted with acute stroke from 2012 to 2014 to the acute stroke-unit at the University Clinic Tulln, Austria. All patients referred to the hospital under suspicion of stroke were directly admitted to the stroke-unit. The diagnosis of stroke was based on clinical presentation and brain imaging (computed tomography [CT] or magnetic resonance imaging [MRI]). A transient ischemic attack (TIA) was diagnosed if clinical symptoms of stroke lasted less than 24 hours and no lesion was detected on the CT or DW-MRI. All patients admitted to the stroke-unit were entered in the Austrian Stroke Unit Registry. The Austrian Stroke Unit Registry collects anonymized, stroke-relevant data on baseline characteristics, management and outcome of all stroke patients admitted to Austrian stroke-units (for more details see [18–19]). All aspects of data entry, data protection, administration and scientific analysis are regulated by law. A formal ethical approval from the local Austrian ethics committee was not needed. Data collection, ratings and data entry were performed by experienced stroke neurologists at the time of admission and discharge to the stroke-unit as well as via follow-up phone call three months thereafter. Stroke severity was assessed on admission and discharge from the stroke-unit using the National Institute of Health Stroke Scale (NIHSS). The modified Rankin Scale (mRS) was used to evaluate functional status before stroke, on admission and discharge from the stroke-unit as well as on follow-up three months later. Vascular risk factors were determined according to medical history, pre-stroke medication or were newly diagnosed during the stay at the stroke-unit. Stroke types were classified on the basis of neuroimaging findings and according to the International Classification of Diseases (ICD)-10 code into ischaemic stroke (I63 or I64) or haemorrhages (I60, I61 or I62). In line with previous evaluations in the acute stroke setting, standard diagnostic criteria were used for assessment of clinical complications .
There were 1394 patients with acute stroke in the stroke registry between 2012 and 2014. Of these, 993 (72.2%) were tested with GUSS within the first 7 days. Of the remaining 401 patients 339 were not tested, 32 were transferred to SLTs for diagnostic reasons other than swallowing disorders (language disorders, facial paralysis) and 30 were tested more than 7 days after admission (Fig 1). Overall 899/1023 (88%) of all patients undergoing a GUSS were tested on the same or the next calendar day, and 939/1023 (92%) within the first three calendar days. The median stroke-unit stay was 2 days (IQR: 1 to 4).
In this cohort of patients admitted with acute stroke or TIA to a stroke-unit, 72% were tested with the GUSS. The GUSS was less often applied in mild strokes as well as in very severe strokes. The GUSS identified patients with the highest risk of SAP and they were assigned to NPO. However, dietary modifications could not prevent pneumonia in all stroke cases—especially not in patients who had already developed severe dysphagia.