TY - JOUR
T1 - Critical illness polyneuropathy in ICU patients is related to reduced motor nerve excitability caused by reduced sodium permeability
AU - Koch, Susanne
AU - Bierbrauer, Jeffrey
AU - Haas, Kurt
AU - Wolter, Simone
AU - Grosskreutz, Julian
AU - Luft, Friedrich C.
AU - Spies, Claudia D.
AU - Fielitz, Jens
AU - Weber-Carstens, Steffen
N1 - Publisher Copyright:
© 2016, Koch et al.
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Background: Reduced motor and sensory nerve amplitudes in critical illness polyneuropathy (CIP) are characteristic features described in electrophysiological studies and due to dysfunction of voltage-gated sodium channels. Yet, faulty membrane depolarization as reported in various tissues of critically ill patients may cause reduced membrane excitability as well. The aim of this study was to compare the pathophysiological differences in motor nerve membrane polarization and voltage-gated sodium channel function between CIP patients and critically ill patients not developing CIP during their ICU stay (ICU controls). Methods: ICU patients underwent electrophysiological nerve conduction studies and were categorized as either ICU controls or CIP patients. Subsequently, excitability parameters were recorded as current-threshold relationship, stimulus-response behavior, threshold electrotonus, and recovery of excitability from the abductor pollicis brevis following median nerve stimulation. Results: Twenty-six critically ill patients were enrolled and categorized as 12 ICU controls and 14 CIP patients. When compared to 31 healthy subjects, the ICU controls exhibited signs of membrane depolarization as shown by reduced superexcitability (p = 0.003), depolarized threshold electrotonus (p = 0.007), increased current-threshold relationship (p = 0.03), and slightly prolonged strength-duration time constant. In contrast, the CIP patients displayed a significantly reduced strength-duration time constant (p < 0.0001), which indicates an increased inactivation of voltage-gated sodium channels. Conclusions: Abnormal motor nerve membrane depolarization is a general finding in critically ill patients whereas voltage-gated sodium channel dysfunction is a characteristic of CIP patients.
AB - Background: Reduced motor and sensory nerve amplitudes in critical illness polyneuropathy (CIP) are characteristic features described in electrophysiological studies and due to dysfunction of voltage-gated sodium channels. Yet, faulty membrane depolarization as reported in various tissues of critically ill patients may cause reduced membrane excitability as well. The aim of this study was to compare the pathophysiological differences in motor nerve membrane polarization and voltage-gated sodium channel function between CIP patients and critically ill patients not developing CIP during their ICU stay (ICU controls). Methods: ICU patients underwent electrophysiological nerve conduction studies and were categorized as either ICU controls or CIP patients. Subsequently, excitability parameters were recorded as current-threshold relationship, stimulus-response behavior, threshold electrotonus, and recovery of excitability from the abductor pollicis brevis following median nerve stimulation. Results: Twenty-six critically ill patients were enrolled and categorized as 12 ICU controls and 14 CIP patients. When compared to 31 healthy subjects, the ICU controls exhibited signs of membrane depolarization as shown by reduced superexcitability (p = 0.003), depolarized threshold electrotonus (p = 0.007), increased current-threshold relationship (p = 0.03), and slightly prolonged strength-duration time constant. In contrast, the CIP patients displayed a significantly reduced strength-duration time constant (p < 0.0001), which indicates an increased inactivation of voltage-gated sodium channels. Conclusions: Abnormal motor nerve membrane depolarization is a general finding in critically ill patients whereas voltage-gated sodium channel dysfunction is a characteristic of CIP patients.
UR - http://www.scopus.com/inward/record.url?scp=85132495013&partnerID=8YFLogxK
U2 - 10.1186/s40635-016-0083-4
DO - 10.1186/s40635-016-0083-4
M3 - Journal articles
AN - SCOPUS:85132495013
SN - 2197-425X
VL - 4
JO - Intensive Care Medicine Experimental
JF - Intensive Care Medicine Experimental
IS - 1
M1 - 10
ER -