Indications and yield of ambulatory EEG recordings.

To study the yield of prolonged ambulatory electroencephalogram (aEEG). A retrospective chart review of all patients who underwent aEEG studies between 2013 and 2017 was performed. Reasons for aEEG were classified into five categories: detection of interictal epileptiform discharges (IEDs), capturing clinical events, detection of unrecognized seizures, monitoring IEDs during treatment, and unclassifiable. Ambulatory EEG reports were reviewed to evaluate whether the study answered the clinical question. A total of 1,264 patients were included. Forty studies were excluded for incomplete data and 234 for being a repeat study. The average number of recording days was 1.57 ± 0.73. Based on initial clinical evaluation, patients carried the following presumptive diagnosis: 61% epilepsy, 11% single unprovoked or acute symptomatic seizure and 28% non-epileptic paroxysmal events (PEs). Overall, focal IEDs were seen in 16.1% of studies, generalized IEDs in 10.8%, focal seizures in 4.1%, and generalized seizures in 1.9%. The most frequent reason for ordering aEEG was to detect IEDs for diagnostic purposes (48.1%). For this indication, additional information was provided by the aEEG in 19.1% of cases (58.6% focal IEDs, 33.5% generalized IEDs, 7.9% seizures without IEDs). Ambulatory EEG was ordered with the intent to capture and characterize clinical events in 18.9%, mostly in patients who reported daily or weekly events. In these, aEEG captured either epileptic seizures or PEs in 102 (42.7%) of the studies (83.3% PEs, 16.7% epileptic seizures). Ambulatory EEG was ordered to evaluate unrecognized seizures in 17.8% of patients, and electrographic seizures were identified in 13.3% of these studies. The yield of aEEG varies based on the indication for the study. Ambulatory EEG can be a useful tool for recording IEDs in the outpatient setting and in a select group of patients to capture clinical events or unrecognized seizures.

Ictal central apneas in temporal lobe epilepsies.

OBJECTIVE: The objective of the study was to examine the frequency and characteristics of ictal central apnea (ICA) in a selective cohort of patients with mesial or neocortical temporal lobe epilepsy (TLE) undergoing surface video-electroencephalography (EEG) and multimodal recording of cardiorespiratory parameters. METHODS: We retrospectively screened 453 patients who underwent EEG in a single center including nasal airflow measurements, respiratory inductance plethysmography of thoracoabdominal excursions, peripheral capillary oxygen saturation, and electrocardiography. Patients with confirmed TLE subtype, either by magnetic resonance imaging (MRI) lesions limited to the temporal neocortex or mesial structures and concordant neurophysiologic data, or patients who underwent invasive explorations were included. RESULTS: Ictal central apnea frequency and characteristics were analyzed in 41 patients with 164 seizures that had multimodal respiratory monitoring. The total occurrence of ICA in all seizures in this cohort was 79.9%. No significant difference was seen between mesial and neocortical temporal lobe seizures (79.8% and 80.0%, respectively). Ictal central apnea preceded EEG onset by 13 ±â€¯11 s in 33.3% of seizures and was the first clinical sign by 18 ±â€¯14 s in 48.7%. Longer ICA duration trended towards a more severe degree of hypoxemia. CONCLUSIONS: In a selective cohort of TLE defined by MRI lesion and/or intracranial recordings, the frequency of ICA was higher than previously reported in the literature. Multimodal respiratory monitoring has localizing value and is generally well tolerated. Ictal central apnea preceded both EEG on scalp recordings as well as clinical seizure onset in a substantial number of patients. Respiratory monitoring and ICA detection is even more paramount during invasive monitoring to confirm that the recorded seizure onset is seen before the first clinical sign.

Positive Expiratory Pressure Therapy With And Without Oscillation And Hospital Length Of Stay For Acute Exacerbation Of Chronic Obstructive Pulmonary Disease.

Introduction: Pharmacologic management of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is well-established. Our aim in the current study is to determine if therapy with a positive expiratory pressure (PEP) device with or without an oscillatory mechanism (OM) in addition to standard care results in a reduction in hospital length of stay (LOS) among patients hospitalized for AECOPD. Methods: Two studies were performed and are reported here. Study 1: Patients admitted with AECOPD and sputum production were enrolled in a prospective trial comparing PEP therapy versus Oscillatory PEP (OPEP) therapy. Study 2: A retrospective historical cohort, matched in a 2 to 1 manner by age, gender, and season of admission, was compared with the prospectively collected data to determine the effect of PEP ± OM versus standard care on hospital LOS. Results: In the prospective trial (Study 1; 91 subjects), median hospital LOS was 3.2 (95% CI 3.0-4.3) days in the OPEP group and 4.8 (95% CI 3.9-6.1) days in the PEP group (p=0.16). In fully adjusted models comparing the prospective trial data with the retrospective cohort (Study 2; 182 subjects), cases had a median hospital LOS of 4.2 days (95% CI 3.8-5.1) versus 5.2 days (95% CI 4.4-6.0) in controls, consistent with a shorter hospital LOS with adjunctive PEP±OM therapy versus standard care (p=0.04). Conclusion: Adjunctive therapy with a PEP device versus standard care may reduce hospital LOS in patients admitted for AECOPD. Although the addition of an OM component to PEP therapy suggests a further reduction in hospital LOS, comprehensive multicenter randomized controlled trials are needed to confirm these findings. Clinical trial registration number: NCT03094806.

Automated seizure detection accuracy for ambulatory EEG recordings.

OBJECTIVE: To investigate the accuracy of preselected software automatic seizure files to detect at least one seizure per study in prolonged ambulatory EEG recording. METHODS: All the prolonged ambulatory EEG recordings (>24 hours) read at the Northwestern Memorial Hospital from January 2013 to October 2017 were included. We selected only the first study of each patient. We reviewed the studies entirely, and processed the recordings through 1 of 3 different detection software that are commercially available (Persyst 11, Persyst 12, and Gotman TM Event Detection). The proportion of patients with at least one electrographic seizure (≥10 seconds) correctly identified by a seizure detector was calculated. Finally, we evaluated whether the type of seizure (focal vs generalized) may affect the chances of being automatically detected. RESULTS: We read 1,478 ambulatory EEG studies entirely (2,323 days of EEG recording; average 1.6 d/study). From the first study of each patient (1,257 studies), we found electrographic seizures in 70 (5.6%) studies. In 37 of 70 patients (53%), the automatic detectors correctly identified at least one seizure. Detections happened slightly more frequently in generalized seizures (14/20, 70%) compared to focal seizures (23/50, 46%) (p = 0.06). CONCLUSION: Seizures were found in 5.6% of the studies. Automatic seizure detectors identified at least one electrographic seizure in only 53% of the studies. They performed slightly better detecting generalized than focal seizures. Therefore, the review of only automatically selected segments may be of decreased value to identify seizures, in particular when focal seizures are suspected.

Continuous positive airway pressure usage in hospitalized patients with known obstructive sleep apnea: discrepancy between admission pressure settings and laboratory-determined settings.

PURPOSE: The aim of this study was to determine the frequency and predictors of correctly initiated continuous positive airway pressure (CPAP) settings on the initial night of hospitalization in patients with known obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: Hospital records of all patients who underwent an outpatient therapeutic polysomnogram (PSG) at our institution between January 2005 and December 2010 were retrospectively reviewed. Data collected included initial CPAP settings on hospital admission, latency to hospitalization (from sleep study), hospital length of stay, demographic variables, and PSG variables. RESULTS: One hundred seventy subjects were included in the analysis: 51 % were male, average age (±SD) was 55.3 ± 13.7 years, and body mass index was 43.7 ± 10.4 kg/m2. OSAHS was generally severe (apnea-hypopnea index (AHI) 52.8 ± 37.3 event/h). Mean CPAP setting during in-laboratory titration was 11.1 ± 3.1 cm H2O and during the first night of hospitalization was 9.5 ± 2.8 cm H2O (p < 0.0001). Of 170 subjects, only 71 (42 %) received the correct laboratory-derived CPAP setting on the first night of hospitalization. In a multivariable logistic regression analysis, higher body mass index (BMI), lower CPAP level determined during PSG, and shorter latency (months) between PSG and hospitalization were associated with receiving the correct CPAP setting during the first night of hospitalization: Each 1 kg/m2 increase in BMI was associated with a 7 % increase odds of receiving the correct CPAP setting during the first night of hospitalization (OR 1.07, 95 % CI 1.02-1.12), while each 1 cm H2O increase in CPAP during PSG and each 1 month longer latency between PSG and hospitalization was associated with a 15 and 7 %, respectively, decrease in the odds of receiving the correct CPAP setting during the first night of hospitalization (CPAP OR 0.85, 95 % CI 0.74-0.97 and latency OR 0.93, 95 % CI 0.90-0.97). There was no in-hospital mortality, and correct CPAP settings did not affect hospital length of stay. CONCLUSIONS: Among patients admitted to the hospital, a correct, laboratory-derived CPAP setting is infrequently prescribed during the first night of hospitalization. Predictors for correctly ordering CPAP include latency from the time of in-laboratory CPAP titration, BMI, and laboratory-derived CPAP level.