Background Chronic non-specific low back pain (CNSLBP) is defined as back pain localised at inferior portion of the rachis, without radiating anywhere else, lasting for more than 12 weeks, and whose etiology cannot be assigned to a specific injury, nerve compression, infection, tumor. This is the case in about 90% of all low back pain subjects. Nowadays physicians are aware that altered breathing patterns may be present in a proportion of individuals with CNSLBP. Researchers suggest that breathing patterns should also be evaluated in the presence of low back pain. Guidelines recommend therapeutic physical exercise as a first line treatment option in CNSLBP. That may be because pain itself contributes to loss of functioning, limits the subject's participation to activities of daily living and produces disability among these subjects. As medication, WHO guideline suggests the use of weak opioids. Tramadol is a centrally acting analgesic, which produces its effect by binding to the μ-opioid receptors, and by inhibiting the release of noradrenaline and serotonine. Studies suggest that, despite its part-opioid mechanism of action, tramadol doesn't produce respiratory depression as opioids do.
Objectives Our study goal was to assess tramadol effects on respiratory markers in human subjects with CNSLBP.
Methods A number of 30 subjects with CNSLBP joined this study for a period of 7 days. They were randomised in two groups: control (15 subjects, received placebo capsules twice a day), tramadol (15 subject, received tramadol 50 mg capsules twice a day). All subjects underwent cardio-pulmonary exercise testing using cycle-ergometer with progressive increasing work-rate at baseline and after 7 days of medication. We investigated peak oxygen uptake (VO2max), respiratory reserve (RR), and exercise tolerance expressed as dioxide carbon ventilatory equivalent. All these parameters were investigated in the first and 7th day of study.
Results Peak oxygen uptake significantly raised for tramadol group on last day of the study (p=0.001). RR improved for both groups but the statistical difference came up for tramadol group (p=0.005). Exercise tolerance was better for both groups but it was significantly higher for tramadol group (p=0.98x10–5).
Conclusions Tramadol administration to subjects with CNSLBP improved respiratory markers and exercise tolerance.
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Disclosure of Interest None declared