INTRODUCTION
Spinal intradural lipomas are rare lesions constituting <1% of all intramedullary spinal cord tumors. Most of the spinal cord lipoma are associated with spinal dysraphism and are usually located in the lumbosacral region.
CASE REPORT
A 9month old female child (Wt-9kg) presented with history of developmental delay. Baby is a first-born child of non-consanguineous full term normal vaginal delivery. Post natal period was uneventful.
Baby was diagnosed to have hydrocephalus at 6th month of age. Physical examination revealed significant increased tone in both the lower limbs.
Radiological workup revealed well-defined T1W1 and T2W1 hyperintense lesion with inversion on TIRM sequence from C5 to T6 suggesting Cervico- dorsal Intramedullary lipoma with Syringohydromyelia and cord oedema inferior to it. Hydrocephalus with likely stenosis of cerebral aqueduct also seen
PRE-OPERATIVE ASSESSMENT
Any type of surgery in the pediatric age group is challenging from securing the venous lines to the airway. This baby with the weight of 9kg for major spinal surgery is also the similar one.
Hence comprehensive surgical and post-operative plan has been discussed extensively with the spine team and the pediatrician and pre-operative assessment for excision of intramedullary lesion has been done.
CBC, RFT, LFT, PTINR, Serology, ECG, Chest Xray was taken and was found to be within the normal limits. Airway could not be assessed. 1 unit of Packed Red Blood cell has been reserved. Counselling regarding the surgery and anesthetic care was made to the parents.
Surgery planned – Debulking Intramedullary spinal lipoma excision from C5 to T6
INTRA-OPERATIVE MANAGEMENT
One peripheral line and right femoral central line 4F triple lumen has been secured. Difficult intubation trolley has been kept ready.
Pre medications such as Inj Pantoprazole 10mg, Inj.Glycopyrrolate 0.1mg (0.005mg – 0.01 mg/kg) and Inj Fentanyl 20mcg i.v were given.
Adequate preoxygenation was done prior to procedure. Baby was induced with Inj Propofol 20mg (1-2.5 mg/kg) and Inj Atracurium 6mg (0.4 – 0.6mg/kg) i.v, intubated with 3.5mm sized Kimberley-Clarke cuffed ET tube and connected to ventilator with Pressure controlled ventilation
Neuro muscular monitor was connected and baby shifted to prone position. Thorough checking of pressure points were made. Gamgee pads were rolled over the body and the warmers were used to prevent hypothermia
Surgery proceeded with Total Intravenous anaesthesia (TIVA) since SSEPs and MEPs were monitored. Muscle relaxant and Nitrous oxide were avoided for the similar purpose.
Maintenance of anesthesia was provided with Inj Propofol at 40mg/hr (50-200 mcg/kg/min) and Inj Fentanyl 20mcg/hr (0.02mg/kg/hr) i.v infusion throughout the procedure
Vitals and urine output were monitored. VBG was taken intra-operatively, showed Hb – 8.2 otherwise normal values. Hence One unit (100ml) PRBC transfused intra-operatively.
SSEPs and MEPs was checked post operatively and compared with pre-operative values. Surgeons and Anesthetists were satisfied with the results.
Baby was successfully extubated at the end of the procedure. Baby was shifted to Neuro ICU post operatively. Vitals were monitored. Baby was started on orals after 4 hours. Necessary post operative care with good analgesics was provided. Baby was clinically stable and hence discharged after 5 days.
Follow-up with Histopathology Reports
Section showed lobules of adipose tissue interspersed by thin fibrous septae and few blood vessels lined by flattened endothelium – features consistent with lipoma
DISCUSSION
Pre operative consideration
When assessing a child for spinal surgery, it is important to adopt a holistic approach. Particular attention should be paid to the condition of respiratory and cardiovascular systems, as impairment of function of these systems can be associated
Vertebral defects can be associated with other congenital anomalies. The VACTERL syndrome – vertebral defects, anorectal malformations, cardiovascular anomalies, transesophageal fistula, renal and limb malformations is seen in 13% of children
Induction and maintenance of anaesthesia
Patients are placed prone and it is important to ensure that the tracheal tubes and lines are secured well before and after turning the patient.
Protection of the eyes and pressure points must be ensured.
Children are more vulnerable to hypothermia because of their greater surface area to body mass ratio. Hypothermic neonates are prone for apnea, bradycardia, hypotension and acidosis. Devices available to minimize intra-operative hypothermia such as warming mattress and warmed fluids should be used.
Monitoring includes ECG, pulse oximetry, capnography, temperature, blood pressure. Central venous pressure monitoring should be undertaken in patients with associated cardiac diseases.
Spinal cord monitoring such as SSEP, Motor evoked potentials are commonly used.
Neurophysiology technicians monitor the latency and amplitude of the recordings continuously during procedure.
A >50% decrease in SSEP amplitude is deemed significant. Volatile agents, cold, hypoxia, hypercarbia and spinal ischemia suppress SSEPs
Spinal surgical procedures have the potential for massive hemorrhage. Preoperative planning should be made regarding blood reservations.
Post operative considerations
Intensive care nursing and necessary post operative analgesia should be made
CONCLUSION
Spinal surgery in children requires a meticulous approach in safety, positioning, with maintenance of normothermia and normovolemia. Neurological deficit can be minimized by careful attention in preoperative assessment and intra operative neuromuscular monitoring
Dr Velmurugan Deisingh
Dr Nirmalraj