Spinal anesthesia: exploring some common surgical myths.
OBJECTIVE: To evaluate and compare whether a difference exists between measurable factors such as heart rate, blood pressure, pulse, and anesthesia induction time in patients undergoing spinal versus general anesthesia. METHODS: A retrospective study of eighteen surgical cases on the leg from the knee and distally under spinal anesthesia were compared to identical or similar procedures performed with a patient under general anesthesia. Data for heart rate, blood pressure, oxygen saturation, and the time interval for anesthesia induction were studied. Heart rate and blood pressure values recorded from the intra-operative anesthesia record were compared with the recorded preoperative values obtained from the anesthesia record. Anesthesia induction time was obtained from the interval between the recorded time for beginning anesthesia and the surgery start time. RESULTS: Systolic blood pressure increased by an average of 12.3 mmHg in the general anesthesia (GA) group compared with a value of 12.9 for the spinal anesthesia (SA) group. Average intra-operative systolic pressure decreased by 10.9 mmHg in the GA group vs. a decrease of 7.7 for SA. Pulse rate for GA decreased by 3.7 bpm versus an increase of 3.2 in SA. Induction time for GA was 27.9 minutes compared to an average SA induction time of 29.8 minutes. CONCLUSIONS: The study found no significant differences in intra-operative patient vital signs when comparing patients under general anesthesia to those under spinal anesthesia. Additionally, although the literature states that spinal anesthesia takes longer if the patient is not prepared prior to the operating room being ready, this study found no significant delay in operation start times for general anesthesia versus spinal anesthesia.