A study published in Spine compares intrathecal and intravenous morphine during minimally invasive spine surgery.
The study authors compared two groups of 25 patients who received either 100 μg of intrathecal or 5±2 mg intravenous morphine. The intravenous morphine was delivered for 24 hours at 2 mL/h following posterior lumbar fusion.
The study found:
1. Patients who received intrathecal morphine reported lower visual analog scores, constipation, lower limb paresthesia and urinary retention.
2. None of the patients in either group reported:
• Vomiting
• Itching
• Nausea
3. Patients in the intrathecal group were more likely to experience urinary retention.
4. The patients in the intravenous group stayed in bed longer postoperatively while patients in the intrathecal group were more likely to mobilize earlier.
5. The study authors concluded that low-dose intrathecal morphine was safe and effective for patients after minimally invasive posterior lumbar interbody fusion and the pain reduction "permitted a shorter hospitalization and earlier mobilization out of bed, augmenting patients' comfort."