Intensive Care Med
https://doi.org/10.1007/s00134-024-07561-x
WHAT’S NEW IN INTENSIVE CARE
Neuromodulation in the intensive care unit
Liang Wu1, Giuseppe Citerio2,3 and Guoyi Gao1,4*
© 2024 The Author(s)
Neuromodulation, through various forms of invasive be used to maintain muscle thickness and strength in
and noninvasive stimulations at the central or peripheral patients with critical illness. A randomized-controlled
level, can enhance or suppress neural activities, offering trial including 140 critically ill patients revealed that daily
the potential for therapeutic intervention. Studies of neu- TEMS sessions prevent the development of CIPNM and
romodulation have reported intriguing clinical outcomes result in a shorter duration of ventilation in the experi-
and promising application prospects across various dis- mental group compared to the control group [1 (0–10)
ciplines, particularly in the realm of novel therapeutic day vs. 3 (0–44) days, median (range), p = 0.003] [3].
modalities. Critically ill patients are commonly suscep- However, some systematic reviews reported no benefi-
tible to intractable systematic dysfunctions due to seda- cial effects of TEMS with low-quality evidence and sug-
tion, immobility, and controlled ventilation. In recent gested that further randomized-controlled trials (RCTs)
years, the application of neuromodulation in the inten- are needed to determine the role of TEMS as an adjuvant
sive care unit (ICU) has increased, and its efficacy has treatment to support patients with muscle weakness in
been tested in multiple scenarios across critical stages of the ICU [1, 4].
the disease process (Fig. 1). Diaphragmatic dysfunction, which is caused by the
Critical illness polyneuromyopathy (CIPNM) is a com- suppression of respiratory muscle activity by seda-
mon complication of patients presenting with muscle tive agents and passive mechanical ventilation, together
weakness in the ICU. CIPNM is associated with a pro- with multiple inflammatory mechanisms, is now widely
longed duration of mechanical ventilation and increased described in patients undergoing mechanical ventila-
mortality in the ICU population. A few preventive tools tion in the ICU. Transcutaneous electrical diaphragmatic
or specific treatments have been proposed for CIPNM. stimulation (TEDS) provides noninvasive stimulation
The pathophysiological mechanisms of transcutaneous through surface electrodes placed bilaterally on the tho-
electrical muscle stimulation (TEMS) may involve an rax over the diaphragm apposition zone. Several teams
anabolic stimulus to the muscle and reversal of the cata- have studied the effects of TEDS, showing that the use
bolic effects of critical illness and immobilization; TEMS of TEDS can decrease diaphragmatic dysfunction and
has been employed as an ancillary treatment in patients improve respiratory muscle strength in patients in the
with severe chronic heart failure and chronic obstruc- ICU [5, 6]. However, a recently published controlled trial
tive pulmonary disease [1]. Acute systemic effects on with 66 patients assessed the impact of daily active elec-
peripheral microcirculation have also been identified [2]. trical stimulation versus sham stimulation on the preven-
Moreover, metabolism-reflex activation during TEMS tion of diaphragm dysfunction during the mechanical
may increase sympathetic excitability and contribute ventilation weaning process [7]. The diaphragm thicken-
to changes in heart rate, systolic blood pressure, blood ing fraction (odds ratio [OR] 1.55, 95% confidence inter-
volume, and cardiac output, thereby affecting muscle val [CI] 0.47–5.1; p = 0.47), maximal inspiratory muscle
metabolism. Neuromuscular electrical stimulation can pressure (35.5 ± 11.9 vs. 29.7 ± 11.7 cmH2O; p = 0.469),
and peak cough flow (83.2 ± 39.5 vs. 75.3 ± 34.08 L/min;
p = 0.83) were similar in the TEDS and sham groups. Fur-
*Correspondence: ther studies are warranted to explore the effectiveness of
1
Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical these treatments in ICU settings.
University, No. 119 Nansihuan Xilu, Fengtai District, Beijing 100070, China
Full author information is available at the end of the article
Vagal nerve stimulation (VNS) has proven beneficial
for patients with refractory epilepsy as a potential adjunct
https://doi.org/10.1007/s00134-024-07561-x
WHAT’S NEW IN INTENSIVE CARE
Neuromodulation in the intensive care unit
Liang Wu1, Giuseppe Citerio2,3 and Guoyi Gao1,4*
© 2024 The Author(s)
Neuromodulation, through various forms of invasive be used to maintain muscle thickness and strength in
and noninvasive stimulations at the central or peripheral patients with critical illness. A randomized-controlled
level, can enhance or suppress neural activities, offering trial including 140 critically ill patients revealed that daily
the potential for therapeutic intervention. Studies of neu- TEMS sessions prevent the development of CIPNM and
romodulation have reported intriguing clinical outcomes result in a shorter duration of ventilation in the experi-
and promising application prospects across various dis- mental group compared to the control group [1 (0–10)
ciplines, particularly in the realm of novel therapeutic day vs. 3 (0–44) days, median (range), p = 0.003] [3].
modalities. Critically ill patients are commonly suscep- However, some systematic reviews reported no benefi-
tible to intractable systematic dysfunctions due to seda- cial effects of TEMS with low-quality evidence and sug-
tion, immobility, and controlled ventilation. In recent gested that further randomized-controlled trials (RCTs)
years, the application of neuromodulation in the inten- are needed to determine the role of TEMS as an adjuvant
sive care unit (ICU) has increased, and its efficacy has treatment to support patients with muscle weakness in
been tested in multiple scenarios across critical stages of the ICU [1, 4].
the disease process (Fig. 1). Diaphragmatic dysfunction, which is caused by the
Critical illness polyneuromyopathy (CIPNM) is a com- suppression of respiratory muscle activity by seda-
mon complication of patients presenting with muscle tive agents and passive mechanical ventilation, together
weakness in the ICU. CIPNM is associated with a pro- with multiple inflammatory mechanisms, is now widely
longed duration of mechanical ventilation and increased described in patients undergoing mechanical ventila-
mortality in the ICU population. A few preventive tools tion in the ICU. Transcutaneous electrical diaphragmatic
or specific treatments have been proposed for CIPNM. stimulation (TEDS) provides noninvasive stimulation
The pathophysiological mechanisms of transcutaneous through surface electrodes placed bilaterally on the tho-
electrical muscle stimulation (TEMS) may involve an rax over the diaphragm apposition zone. Several teams
anabolic stimulus to the muscle and reversal of the cata- have studied the effects of TEDS, showing that the use
bolic effects of critical illness and immobilization; TEMS of TEDS can decrease diaphragmatic dysfunction and
has been employed as an ancillary treatment in patients improve respiratory muscle strength in patients in the
with severe chronic heart failure and chronic obstruc- ICU [5, 6]. However, a recently published controlled trial
tive pulmonary disease [1]. Acute systemic effects on with 66 patients assessed the impact of daily active elec-
peripheral microcirculation have also been identified [2]. trical stimulation versus sham stimulation on the preven-
Moreover, metabolism-reflex activation during TEMS tion of diaphragm dysfunction during the mechanical
may increase sympathetic excitability and contribute ventilation weaning process [7]. The diaphragm thicken-
to changes in heart rate, systolic blood pressure, blood ing fraction (odds ratio [OR] 1.55, 95% confidence inter-
volume, and cardiac output, thereby affecting muscle val [CI] 0.47–5.1; p = 0.47), maximal inspiratory muscle
metabolism. Neuromuscular electrical stimulation can pressure (35.5 ± 11.9 vs. 29.7 ± 11.7 cmH2O; p = 0.469),
and peak cough flow (83.2 ± 39.5 vs. 75.3 ± 34.08 L/min;
p = 0.83) were similar in the TEDS and sham groups. Fur-
*Correspondence: ther studies are warranted to explore the effectiveness of
1
Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical these treatments in ICU settings.
University, No. 119 Nansihuan Xilu, Fengtai District, Beijing 100070, China
Full author information is available at the end of the article
Vagal nerve stimulation (VNS) has proven beneficial
for patients with refractory epilepsy as a potential adjunct
