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Background and Aims In addition, commonly known as neurotransmitters properties of some purines. Concentration of purines as neurotransmitters, may be correlated with characteristics of neuraxial block in spinal anesthesia.

Methods We examined 30 pregnant women, who before starting spinal anesthesia for cesarean section was performed over the fence of venous blood, in the performance of spinal anesthesia (before the introduction of anesthesia) - fence CSF. Contents of purine bases was determined direct spectrophotometry in blood serum or cerebrospinal fluid in each of the purine metabolite wavelengths. Take into account the following characteristics of spinal anesthesia administered dose of mg spinal ropivacaine, speed of onset, depth and height of the spread of spinal block, the need for additional administration of intravenous analgesics and anesthetics.

Results Dose spinal ropivacaine correlated with blood guanine (r=0,73; p=0,040), hypoxanthine (r=0,82; p=0,013), adenine (r=0,77; p=0,023) and xanthine (R=0,71; p=0,046). Time of onset of adequate spinal block correlated with the blood guanine (r=0,89; p=0,003), hypoxanthine (r=0,85;p=0,008), xanthine (r=0,73; p=0,040), uric acid (r=0,78; p=0,022). Spinal block height correlated with blood guanine (R=0,74;p=0,035), and xanthine (R=0,71;p=0,048). Mothers with high-quality, adequate spinal block, which do not require the additional use of intravenous anesthetics differed from women with a low, not enough adequate spinal block, a lower concentration of guanine in blood serum (Mann-Whitney U Test, p=0,043)

Conclusions The level of guanine in blood serum can be used to predict the quality of spinal anesthesia in obstetrics, possibly to define indications for preemptive use of combined spinal-epidural or general anesthesia instead of the single-stage single-dose spinal anesthesia.