TY  - JOUR
A1  - Stetter, Christian
A1  - Weidner, Franziska
A1  - Lilla, Nadine
A1  - Weiland, Judith
A1  - Kunze, Ekkehard
A1  - Ernestus, Ralf-Ingo
A1  - Muellenbach, Ralf Michael
A1  - Westermaier, Thomas
T1  - Therapeutic hypercapnia for prevention of secondary ischemia after severe subarachnoid hemorrhage: physiological responses to continuous hypercapnia
JF  - Scientific Reports
N2  - Temporary hypercapnia has been shown to increase cerebral blood flow (CBF) and might be used as a therapeutical tool in patients with severe subarachnoid hemorrhage (SAH). It was the aim of this study was to investigate the optimum duration of hypercapnia. This point is assumed to be the time at which buffer systems become active, cause an adaptation to changes of the arterial partial pressure of carbon dioxide (PaCO2) and annihilate a possible therapeutic effect. In this prospective interventional study in a neurosurgical ICU the arterial partial pressure of carbon dioxide (PaCO\(_2\)) was increased to a target range of 55 mmHg for 120 min by modification of the respiratory minute volume (RMV) one time a day between day 4 and 14 in 12 mechanically ventilated poor-grade SAH-patients. Arterial blood gases were measured every 15 min. CBF and brain tissue oxygen saturation (StiO\(_2\)) were the primary and secondary end points. Intracranial pressure (ICP) was controlled by an external ventricular drainage. Under continuous hypercapnia (PaCO\(_2\) of 53.17 ± 5.07), CBF was significantly elevated between 15 and 120 min after the start of hypercapnia. During the course of the trial intervention, cardiac output also increased significantly. To assess the direct effect of hypercapnia on brain perfusion, the increase of CBF was corrected by the parallel increase of cardiac output. The maximum direct CBF enhancing effect of hypercapnia of 32% was noted at 45 min after the start of hypercapnia. Thereafter, the CBF enhancing slowly declined. No relevant adverse effects were observed. CBF and StiO\(_2\) reproducibly increased by controlled hypercapnia in all patients. After 45 min, the curve of CBF enhancement showed an inflection point when corrected by cardiac output. It is concluded that 45 min might be the optimum duration for a therapeutic use and may provide an optimal balance between the benefits of hypercapnia and risks of a negative rebound effect after return to normal ventilation parameters.
KW  - cerebrovascular disorders
KW  - clinical trials
KW  - neurology
KW  - neurovascular disorders
KW  - Phase II trials
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260779
VL  - 11
IS  - 1
ER  - 
TY  - JOUR
A1  - Tischer, Christina
A1  - Stupp, Carolin
A1  - Janson, Patrick
A1  - Willeke, Kristina
A1  - Hung, Chu-Wei
A1  - Flöter, Jessica
A1  - Kirchner, Anna
A1  - Zink, Katharina
A1  - Eder, Lisa
A1  - Hackl, Christina
A1  - Mühle, Ursula
A1  - Weidmann, Manfred
A1  - Nennstiel, Uta
A1  - Kuhn, Joseph
A1  - Weidner, Christian
A1  - Liebl, Bernhard
A1  - Wildner, Manfred
A1  - Keil, Thomas
T1  - Evaluation of screening tests in Bavarian healthcare facilities during the second wave of the SARS-CoV-2 pandemic
JF  - International Journal of Environmental Research and Public Health
N2  - Due to the lack of data on asymptomatic SARS-CoV-2-positive persons in healthcare institutions, they represent an inestimable risk. Therefore, the aim of the current study was to evaluate the first 1,000,000 reported screening tests of asymptomatic staff, patients, residents, and visitors in hospitals and long-term care (LTC) facilities in the State of Bavaria over a period of seven months. Data were used from the online database BayCoRei (Bavarian Corona Screening Tests), established in July 2020. Descriptive analyses were performed, describing the temporal pattern of persons that tested positive for SARS-CoV-2 by real-time polymerase chain reaction (RT-PCR) or antigen tests, stratified by facility. Until 15 March 2021, this database had collected 1,038,146 test results of asymptomatic subjects in healthcare facilities (382,240 by RT-PCR, and 655,906 by antigen tests). Of the RT-PCR tests, 2.2% (n = 8380) were positive: 3.0% in LTC facilities, 2.2% in hospitals, and 1.2% in rehabilitation institutions. Of the antigen tests, 0.4% (n = 2327) were positive: 0.5% in LTC facilities, and 0.3% in both hospitals and rehabilitation institutions, respectively. In LTC facilities and hospitals, infection surveillance using RT-PCR tests, or the less expensive but less sensitive, faster antigen tests, could facilitate the long-term management of the healthcare workforce, patients, and residents.
KW  - SARS-CoV-2
KW  - asymptomatic screening
KW  - RT-PCR
KW  - antigen testing
KW  - infection surveillance
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242637
SN  - 1660-4601
VL  - 18
IS  - 14
ER  -