Effects Of Spinal Anesthesia In Prone Position For Patients Underwent Perianal Surgery On Anesthesia Effectiveness

Objective To compare the effects on lumbar anesthesia blocking surface and hemodynamic brought by combined spinal-epidural anesthesia (CSEA) for penitents in prone position during different time periods and find a rational, safe and highly efficient anesthesia method for surgeries in prone position.Methods 80 randomly selected patients scheduled for anal-enteral surgeries on prone position, in whom combined spinal-epidural anesthesia (CSEA) is applied, are 17 74 years old and ASA physical statusâ… ^â…¡, and are divided into 2 groups randomly: Group A, also the experimental group is subdivided into A1 and A2; group B, the control group, is subdivided into group B1 and group B2. Each subgroup has 20 patients. 80 patients should get gastrointestinal tract ready for surgeries one day before operation, and is continually monitored after patients entering in operation room. Patients lie on the bed quietly and take record of the foundation values of ECG,HR,R,Sp0₂,and BP 10 minutes later after performed with 0.15ml/kg.min Lactated Ringer's solution, then begin with anesthesia. The speed of injection into subarachnoid space is at 1ml/5S, and application of combined spinal-epidural anesthesia (CSEA) is at L_{3 4} puncture place. Group A₁: After injection into subarachnoid space with 7.5mg of 0.5% isobaric bupivacaine, patients change to prone position immediately; group A₂: After injection into subarachnoid space with 5mg of 0.5% isobaric bupivacaine, patients change to prone position immediately; group B₁: After injection into subarachnoid space with 7.5mg of 0.5% isobaric bupivacaine, patients lie down on their back 15 minutes later, then change to prone position; group B₂: After injection into subarachnoid space with 5mg of 0.5% isobaric bupivacaine, patients lie down on their back 15 minutes later, then change to prone position. The time of sensory block occur, the time of sensory block reaching to the maximum plane and the maximum plane of sensory block are observed and compared. The motor block is evaluated by improved Bromage scale; the change of hemodynamics, the time between anesthesia and operation are recorded at 1min, 3min, 5min, 10min, 20min, and 30min when in prone position; the scores of patients satisfaction, the incidence and numbers of hypotension, bradycardia , respiratory depression, shivering, nausea and vomit, and autonomic micturation after operation are recorded. Results There is no significant differences between the onset time of sensory block and the time when sensory block reaching to maxlmum plane (P>0.05) among two groups of patients. There is a statistical difference between the Bromage scale sub-groupA₁, sub-groupA₂, sub-groupB₁, and sub-groupB₂ (P<0.05), yet there is no difference between group A and group B. No blood pressure or heart rate decrease, respiratory depression, shivering, nausea and vomit, and headache after operation occurred among patients in each groups; the incidence rate of shivering has no statistical significance(P>0.05) among four groups. The scores of satisfaction after operation are allâ… . The interval time between anesthesia start time and operation beginning time in group A is obviously less than that of time in group B(P<0.05). The incidence rate of urinary retentron in group A₁ is less than that of rate in group A₂; so is group B₁ and group B₂. There is no significant difference between group A and group B (P>0.05).Conclusions 5mg and 7.5 mg of 0.5% isobaric bupivacaine for combined spinal-epidural anesthesia (CSEA) in patients undergoing anal-enteral surgeries in prone position have proven to have good effects, and also have very little effects on hemodynamics. 5mg bupivacaine can achieve the purpose of anesthesia for anal-enteral surgeries and assure a relatively lower incidence rate of urinary retentron. It is safe and feasible for patients to stay immediately in prone position after injection into subarachnoid space for anesthesia, and it also reduces the time of waiting for operation.