A growing number of children are being implanted with magnetically controlled growing rods. Some also have baclofen pumps, a device that delivers a neuromodulating medication using a magnet. There has been no previous testing to determine if the External Remote Controller (ERC) would stall the baclofen pump during magnetic rod lengthening, a potentially life-threatening event.

Two baclofen pumps, 20 mL and 40 mL, were placed in varying proximity to the ERC while the magnetic field was generated. The speed (dose) of the baclofen pump, the distance from the ERC, the length of time the ERC was run, the position of the pump in relationship to the magnetic field, and the presence or absence of a stall were recorded.

To stall a baclofen pump, the ERC needed to be running continuously for at least 30 mm of lengthening (about 3 minutes). The pump would not stall if it was more than 1 cm away from the ERC, even if the ERC generated a field for 3 minutes. The speed of the pump did not affect the instance of a motor stall. The pump was more likely to stall if it was positioned in front of or behind the magnetic field, as opposed to the center of the field.

Baclofen pumps are always more than 1 cm away from the magnetic rods when both are implanted in a child. The typical lengthening interval is under 10 mm, much less than what was required to stall a baclofen pump. The ERC is highly unlikely to stall a baclofen pump during a magnetic rod lengthening, making a life-threatening event almost impossible.

Intrathecal morphine (IM) is a common adjunct in paediatric spinal deformity surgery. We previously demonstrated with idiopathic scoliosis it provides safe and effective analgesia in the immediate postoperative period. This study represents our 25 year experience with IM in all diagnostic groups.

Our prospective Pediatric Orthopaedic Spine Database (1993–2018) was reviewed to identify all patients undergoing spinal deformity surgery who received IM and who did not. Patients 21 years of age or less who had a posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI), and received 9–19 mcg/kg (up to 1 mg) of IM were included. Early onset scoliosis surgical patients were excluded. We assessed demographics, pain scores, time to first dose of opioids, diagnoses, surgical time, paediatric intensive care unit (PICU) admission and IM complications (respiratory depression, pruritus, nausea/ vomiting).

There were 986 patients who met inclusion criteria. This included 760 patients who received IM and 226 who did not. IM was not used for short procedures (< 3 hrs), respiratory concerns, unsuccessful access of intrathecal space, paraplegia, and anesthesiologist decision. Both groups followed the same strict perioperative care path. The patients were divided into 5 diagnostic groups (IM / non IM patients): idiopathic (578/28), neuromuscular (100/151), syndromic (36/17), and congenital scoliosis (32/21) and kyphosis (14/9). Females predominated over males (697/289). The first dose of opioids after surgery was delayed for a mean of 10.6 hrs in IM group compared to 2.3 hrs in the non-IM group (p=0.001). The postoperative pain scores were significantly lower in the IM groups in the Post Anesthesia Care Unite (p=0.001). Only 17 IM patients (2%) were admitted to the PICU for observation secondary to respiratory depression, none required re-intubation. None of the IM group were re-intubated. Forty-nine patients (6%) experienced pruritus in the IM group compared to 4 of 226 patients (2%) in the non IM group. There were 169 patients (22%) of the IM patients and 21 patients (9%) of the non IM had nausea and vomiting postoperatively. Three patients (0.39%) had a dural leak from the administration of IM but did not require surgical repair. There were no other perioperative complications related to the use of IM. There were no significant group differences.

Pre-incision IM is a safe and effective adjunct for pain management in all diagnostic groups undergoing spinal surgery. The IM patients had lower pain scores and a longer time to first administration of post-operative opioids. Although there is an increased frequency of respiratory depression, pruritus, and nausea/vomiting in the IM group, there were no serious complications.