[Use of 2 % hyperbaric prilocaine for spinal anesthesia : sensitivity analysis in outpatient surgery].

BACKGROUND

Hyperbaric prilocaine 2 % has been available for spinal anesthesia in Germany for 2 years and is characterized by a short duration of action, a lack of postspinal urine retention and a reduction of transient neurological syndromes. However, desirable pharmacological properties are contrasted by higher pharmacological costs compared to hyperbaric bupivacaine 0.5 %.

MATERIALS AND METHODS

This paper deals with a sensitivity analysis for the use of hyperbaric prilocaine 2 % versus hyperbaric bupivacaine 0.5 % in Germany and investigates the financial break-even point up to which time a shorter patient stay in the recovery area compensates for the higher costs for the use of prilocaine 2 % for ambulatory spinal aaesthesia. A sensitivity analysis is an instrument of investment appraisal. It is a model to reduce a complex system with numerous variables to a straightforward calculation by assuming a framework requirement and systematically changing only one or two variables. In this paper additional costs for spinal anesthesia have been neglected, only the time a nurse spends with the patient in the recovery area and the costs for each vial of drug have been taken into account.

RESULTS

For the assumption of 75 min time until leaving the recovery area and being discharged after spinal anesthesia with hyperbaric prilocaine 2 % versus 150 min (recovery of motor competence) or 405 min (voiding) with hyperbaric bupivacaine 0.5 % the calculation shows a cost benefit for hyperbaric prilocaine 2 % of EUR 11.64 or EUR 64.76 compared to hyperbaric bupivacaine 0.5 % and EUR 13.32 or EUR 66.44 compared to isobaric bupivacaine 0.5 %. Under the assumption that all patients who have received spinal anesthesia with hyperbaric bupivacaine 0.5 % can be discharged from the recovery area after 150 min, the use of hyperbaric prilocaine 2 % remains more economical as long as the patient is discharged from the recovery area within 130 min. If 405 min recovery time is assumed for hyperbaric bupivacaine 0.5 % the costs compared with hyperbaric prilocaine 2 % will be compensated after 300 min. To be more economical compared to patients with hyperbaric prilocaine 2 % those who received hyperbaric bupivacaine 0.5 % must be discharged from the recovery area within at least 100 min. However, a time of less than 160 min for discharge from the recovery area is not published anywhere in the literature. In summary, the use of hyperbaric prilocaine 2 % for 60 min operation time is cheaper than the use of bupivacaine 0.5 % as long as patients do not stay in the recovery area for longer than 120 min and are discharged from the recovery area.

CONCLUSIONS

For German framework conditions the use of hyperbaric prilocaine 2 % can provide an economical advantage compared to the use of hyperbaric bupivacaine 0.5 % if staff assignment can be flexible.