home : about us : ahead of print : current issue : archives search instructions : subscriptionLogin 
Users online: 7175      Small font sizeDefault font sizeIncrease font size Print this page Email this page

Previous Article  Table of Contents  Next Article  
Ahead of print publication

Paroxysmal sympathetic hyperactivity after severe traumatic brain injury in children: A retrospective case series

1 Department of Anaesthesiology, ABVIMS & Ram Manohar Lohia (RML) Hospital, New Delhi, India
2 Department of Anaesthesiology and Critical Care, Sharda University School of Medical Sciences and Research, Greater Noida, Uttar Pradesh, India
3 Department of Neuroanaesthesia, Institute of Human Behaviour and Allied Sciences (IHBAS), New Delhi, India
4 Department of Neuroanaesthesiology and Critical Care, All India Institute of Medical Sciences (AIIMS), New Delhi, India
5 Department of Anaesthesia and Critical Care, Rajiv Gandhi Cancer Institute & Research Centre, New Delhi, India

Date of Submission04-Dec-2021
Date of Acceptance24-Jan-2022
Date of Web Publication15-Oct-2022

Correspondence Address:
Ankur Khandelwal,
Department of Anaesthesiology and Critical Care, Sharda University School of Medical Sciences and Research, Greater Noida, Uttar Pradesh
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jpn.JPN_218_21



Paroxysmal sympathetic hyperactivity (PSH), a common sequelae of traumatic brain injury (TBI), is a clinical condition characterized by features of sympathetic hyperactivity. Though there is a substantial literature on adults, the data on children are lacking. We did a retrospective analysis of severe TBI (Glasgow Coma Scale [GCS] ≤8) pediatric patients over a period of 1 year. PSH was noted in 16.7% (5/30) of the children after severe TBI. The mean (standard deviation, SD) age of the patients was 3.4 (1.14) years. The mean (SD) time to occurrence of PSH after TBI was found to be 12.8 (1.92) days. All five cases responded to therapies usually advocated for the management of PSH in adults with a mean duration of recovery of 4.2 (1.09) days. Early diagnosis and prompt treatment initiation is the key to manage PSH.

Keywords: Children, Glasgow coma scale, paroxysmal sympathetic hyperactivity, traumatic brain injury

How to cite this URL:
Nayak SS, Khandelwal A, Rajagopalan V, Rath GP, Routaray SK. Paroxysmal sympathetic hyperactivity after severe traumatic brain injury in children: A retrospective case series. J Pediatr Neurosci [Epub ahead of print] [cited 2023 Dec 4]. Available from: https://www.pediatricneurosciences.com/preprintarticle.asp?id=359343

   Introduction Top

P  aroxysmal sympathetic hyperactivity (PSH)   or autonomic storm that occurs as sequelae of acute brain injury (ABI) is typically characterized by paroxysmal episodes of hyperthermia, hypertension, tachycardia, tachypnea, diaphoresis, and dystonia. Though the exact mechanism is still not very clear, the plausible pathophysiology includes disinhibition of diencephalic autonomic centers leading to sympathetic surge.[1] Predominantly, PSH is seen after traumatic brain injury (TBI) with incidence reported between 8% and 33% in adults.[1],[2] Though the incidence is relatively less in children (≅12%),[3],[4] the final pathway in both the age groups includes difficulty in weaning from mechanical ventilation (MV), increased intensive care unit (ICU), and hospital stay and poorer neurological outcomes.[1],[2],[3],[4] We did a retrospective analysis of severe TBI (Glasgow Coma Scale [GCS] ≤8) patients admitted to our ICU over a period of 1 year. Of the 30 patients with severe TBI, 5 patients developed PSH. In this case series, we also report the successful management of these cases which is focused predominantly on early diagnosis and prompt treatment initiation.

   Case 1 Top

A 2-year-old male child with an alleged history of fall from 12 feet height presented to our emergency department (ED) with loss of consciousness (LOC) and two episodes of vomiting. Due to low initial GCS comprising of eye response (E):1, verbal response (V):1, and motor response (M):4, intubation of trachea was done. A noncontrast computed tomography (NCCT) of the head was done, which showed features suggestive of diffuse axonal injury (DAI). On arrival in the ICU, the GCS of the child was E1VTM5. The child was sedated with midazolam and fentanyl infusion and intracranial pressure (ICP) catheter (parenchymal) was placed. The initial ICP ranged between 18 and 22 mm Hg. The child was managed conservatively and intracranial hypertension was treated as per recommendations. We prefer to use 3% hypertonic saline (HTS) instead of mannitol in children. The ICP catheter was removed on the sixth day following ICP normalization. However, the child continued to have a GCS motor score of 5. We gradually tapered the sedation and initiated pressure support ventilation (PSV). On the 10th day, the GCS improved to E3VTM6. Intermittent spontaneous T-piece trials were given. However, on the 14th day, the patient developed episodes of fever, diaphoresis, hypertension, tachycardia, tachypnea, and motor posturing. The episodes continued in paroxysms. Acute episodes were aborted using bolus dose of intravenous (IV) midazolam and fentanyl. IV acetaminophen was administered 8 hourly for control of fever. Once all the routine investigations including cultures excluded infectious etiology, a diagnosis of PSH was made and definitive treatment was initiated with tab propranolol 5 mg twice daily and tab baclofen 2.5 mg twice daily through a nasogastric tube. Later, the dose of propranolol was increased to tab 10 mg twice daily. Within 4 days, the PSH symptoms were controlled and tracheal extubation was done on the 18th day. The patient remained well thereafter and was discharged from the hospital on the 22nd day.

   Case 2 Top

A 3-year-old male child with an alleged history of fall from 8-feet height presented to our ED with LOC and one episode of seizure. The GCS on presentation was E1V1M4. Tracheal intubation was done in the ED. NCCT head showed bilateral parietal bone fracture with a right frontoparietal contusion, intraventricular hemorrhage (IVH), and interhemispheric subarachnoid hemorrhage (SAH). The patient was shifted to ICU where an ICP catheter was placed. The initial ICP ranged between 28 and 30 mm Hg. The patient was sedated with midazolam and fentanyl infusion and mechanically ventilated. Also, 3% HTS was administered. However, the ICP persistently remained above 25 mm Hg, and so, the patient was taken up for right-sided frontotemporoparietal (FTP) decompressive craniectomy with lax duroplasty. The patient was managed in the ICU postoperatively. Sedation and ventilation were continued. On the 9th postoperative day (POD), the GCS improved to E4VTM6. Sedation was stopped and weaning initiated. However, on day 12, the patient showed classical features of PSH. After excluding all other causes, PSH was diagnosed and management was done in a similar way as described in Case 1. The extubation of trachea was done on 17th POD after resolution of PSH features. The child was discharged from the hospital on 22nd POD.

   Case 3 Top

In this case, a 4-year-old male child following an alleged history of fall presented with LOC and one episode of vomiting. His initial GCS was E1V1M5. NCCT of head showed left parietal bone fracture with small extradural hemorrhage (EDH) in the left parietal region, diffuse cerebral edema, and mass effect. Conservative management with ICP monitoring was planned. The child was electively ventilated under sedation with IV midazolam and fentanyl infusion. On day 10, his GCS improved to E3VTM6. On day 13, the patient developed features of PSH. The final diagnosis was made after excluding other causes. Tab propranolol 5 mg twice daily and tab baclofen 2.5 mg were started along with sedation of midazolam and fentanyl. However, not witnessing much improvement even after 48 h of treatment, dose of propranolol was increased to 10 mg twice daily and later on, tab clonidine 50 mcg once daily was started. The symptoms subsided in another 2 days. The trachea was extubated on day 19 and the patient was discharged from the hospital on day 26.

   Case 4 Top

A 3-year-old female child with bilateral frontoparietal thin SDH, SAH, and diffuse cerebral edema was referred to our hospital from another center on day 3 of her head injury. On admission to our hospital, her GCS was E1VTM3. She also had bilateral intercostal drains (ICDs) in situ as she had also suffered bilateral pneumothorax. Conservative management with invasive ICP monitoring, MV, and sedation were commenced. On day 7, ICDs were removed following bilateral lung expansion. On day 8, ICP catheter was removed. Sedation was gradually tapered and GCS improved to E3VTM5 by day 11. Anticipating the need for prolonged MV, the child was tracheotomized on day 13 of injury. On day 15, the patient developed features suggestive of PSH. The treatment included sedation with midazolam and fentanyl, tablet propranolol 10 mg twice daily and baclofen 2.5 mg BD. The symptoms resolved in another 4 days and GCS improved to E4VTM6. Decannulation of tracheostomy tube was done after 7 days and the patient was discharged from the hospital on day 31.

   Case 5 Top

A 5-year-old female child following an alleged history of fall presented to us with LOC, one episode of vomiting and right-sided weakness. Her initial GCS was E1VTM4. NCCT of the head showed hemorrhage in the left side basal ganglia region with mass effect and midline shift of approximately 6 mm. Left-sided FTP decompressive craniectomy was done. In the postoperative period, the child was electively ventilated and sedated. The GCS on the POD 3 improved to E2VTM5. On POD 10, the child developed features of PSH. In this case too, the treatment included sedation and MV, tab propranolol 5 mg twice daily and clonidine 50 mcg once daily. Baclofen was not given as dystonia was not classically seen. The symptoms improved in the next 3 days and GCS improved to E4VTM6 following which the extubation of trachea was done. The patient was discharged from the hospital on POD 22.

   Discussion Top

PSH that occurs due to dissociation between the sympathetic and parasympathetic nervous systems was first described by Wilder Penfield in 1929 in a patient with TBI.[5] The diagnosis is made based on the presence of any four of the following features: hyperthermia, hypertension, tachycardia, tachypnea, diaphoresis, and dystonia in the absence of other causative factors like sepsis, seizures, hypoxia, hypoglycemia, and pain.[1],[2] Though the criteria have been originally concocted for the diagnosis of PSH in adults, the same is followed in children. Recent studies have suggested that three of the core symptoms such as hypertension, diaphoresis, and dystonia, can be considered as predictive signs of pediatric PSH relative to adults.[6] In addition, the hypercatabolic nature of the condition leads to immunosuppression and weight loss.[7] PSH in children has been reported after TBI, anoxic brain injury, brain tumors, central nervous system infections, stroke, and moyamoya disease.[3],[4],[6],[7]

In this case series, PSH was noted in 16.7% of the children after severe TBI, marginally higher than previously reported. This is attributed to the recent literatures providing evocative insights into the diagnostic criteria of PSH in children after ABI. We excluded two patients from the study due to the lack of complete information from their records. The mean (standard deviation, SD) age of the patients was 3.4 (1.14) years. From this case series, it is difficult to comment on gender preponderance as three patients were males and two were females. The mean (SD) time to occurrence of PSH after TBI was found to be 12.8 (1.92) days and a period as early as 10 days.

Previous reports have mentioned DAI as the most important cause for PSH owing to the mechanism of disruption of multiple white matter tracts leading to disintegration of the central autonomic network.[4] However, in this case series, diagnosis other than DAI also contributed to the development of PSH. Indeed, severe TBI rather than type of radiological diagnosis is probably more significant for the occurrence of PSH. It has been suggested that the paroxysm of sympathetic symptoms may be a response to structural or functional impairment of the midbrain in TBI patients as it has been seen that patients with less brainstem involvement have a shorter duration of paroxysm and a much easier recovery of upper-spinal inhibition.[8]

The potential benefits of treatment for PSH may result from the three main goals: eliminating predisposing causes, mitigating excessive sympathetic outflow, and supportive therapy. Though the drug therapy for the treatment of PSH in children is not very clearly outlined in the literature, in this case series, all the five patients responded to drugs that have been widely described for adults. These include benzodiazepines, opioids, α-blocker (propranolol), and α-adrenergic agonists (clonidine, dexmedetomidine).[1],[8] Neuroprotective effects of beta-blockers may be mediated through decreased cerebral blood flow and decreased oxygen and glucose consumption, thus reducing cerebral metabolism.[9],[10] In addition, acetaminophen and baclofen are added for control of fever and muscle spasticity (and consequent pain), respectively. Furthermore, a uniform approach to management is merited in children to promote healing and recovery which include facilitation of family presence and manipulation of the physical environment (auditory, tactile, visual stimuli).[7]

The mean (SD) time to resolution of PSH features as its onset was found to be 4.2 (1.09) days, much earlier than that reported in adults. This allowed successful extubation of trachea in four cases. Overall, the prognosis seems to be better in children although the existing literature has highlighted that children with dysautonomia tend to experience longer rehabilitation and worse functional outcome.[3],[6] As such, more studies with a large sample size are warranted in children to understand the disease course. Moreover, the long-term effects such as cognitive and motor functions should be studied in future trials.

   Conclusion Top

Children with severe TBI have a high probability of developing PSH. Early diagnosis and prompt treatment helps in hemodynamic stabilization, reduces the need for sedative medications, and leads to improvement in GCS and weaning from MV. However, studies in larger population have to be carried out systematically to support our observation.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

   References Top

Zheng RZ, Lei ZQ, Yang RZ, Huang GH, Zhang GM. Identification and management of paroxysmal sympathetic hyperactivity after traumatic brain injury. Front Neurol 2020;11:81.  Back to cited text no. 1
Baguley IJ, Slewa-Younan S, Heriseanu RE, Nott MT, Mudaliar Y, Nayyar V. The incidence of dysautonomia and its relationship with autonomic arousal following traumatic brain injury. Brain Inj 2007;21:1175-81.  Back to cited text no. 2
Krach LE, Kriel RL, Morris WF, Warhol BL, Luxenberg MG. Central autonomic dysfunction following acquired brain injury in children. J Neurol Rehab 1997;11:41-5.  Back to cited text no. 3
Deepika A, Mathew MJ, Kumar SA, Devi BI, Shukla D. Paroxysmal sympathetic hyperactivity in pediatric traumatic brain injury: a case series of four patients. Auton Neurosci 2015;193:149-51.  Back to cited text no. 4
Penfield W. Diencephalic autonomic epilepsy. Arch Neurol 1929;22:358-74.  Back to cited text no. 5
Kirk KA, Shoykhet M, Jeong JH, Tyler-Kabara EC, Henderson MJ, Bell MJ, et al. Dysautonomia after pediatric brain injury. Dev Med Child Neurol 2012;54:759-64.  Back to cited text no. 6
Letzkus L, Keim-Malpass J, Anderson J, Kennedy C. Paroxysmal sympathetic hyperactivity in children: an exploratory evaluation of nursing interventions. J Pediatr Nurs 2017;34:e17-21.  Back to cited text no. 7
Meyfroidt G, Baguley IJ, Menon DK. Paroxysmal sympathetic hyperactivity: the storm after acute brain injury. Lancet Neurol 2017;16:721-9.  Back to cited text no. 8
Schmalbruch IK, Linde R, Paulson OB, Madsen PL. Activation-induced resetting of cerebral metabolism and flow is abolished by beta-adrenergic blockade with propranolol. Stroke 2002;33:251-5.  Back to cited text no. 9
Schroeppel TJ, Sharpe JP, Magnotti LJ, Weinberg JA, Clement LP, Croce MA, et al. Traumatic brain injury and β-blockers: not all drugs are created equal. J Trauma Acute Care Surg 2014;76:504-9; discussion 509.  Back to cited text no. 10


Previous Article   Next Article


   Ahead of print
     Search Pubmed for
    -  Nayak SS
    -  Khandelwal A
    -  Rajagopalan V
    -  Rath GP
    -  Routaray SK

   Case 1
   Case 2
   Case 3
   Case 4
   Case 5

 Article Access Statistics
    PDF Downloaded30    

Recommend this journal