ISSN: 2155-6148
Isabel Forés, Enrique Lloria* , Isabel Asensio
Background: General anesthesia and sedation techniques with local anesthesia have been the choice in Major Ambulatory Surgery (MAS) compared to intrathecal techniques, which are used when complications of general anesthesia may be greater (difficult airway, Chronic Obstructive Pulmonary Disease (COPD) or risk of airborne infection). We currently use prilocaine, although its great individual variability can cause delays in patient discharge or unexpected admissions. Due to its more predictable pharmacokinetic profile and short duration of motor block, intrathecal 1% chloroprocaine could represent a useful tool in MAS.
Methods: 103 inguinal hernia surgery patients were randomly assigned into two groups, one receiving 50 mg of 1% intrathecal chloroprocaine and the other 50 mg of 2% hyperbaric prilocaine. The primary outcome was the percentage of patients who could start walking 2 hours after dural puncture. Secondary variables were: Percentage of patients with ambulation at 2.5 and 3 hours; delayed time to discharge; total length of stay in the MASU; unexpected admissions, complications in postoperative period, pain intensity at admission and discharge from the MASU; satisfaction with the technique used and outpatient care.
Results: 5 patients of the original 103 were excluded from the study, so 98 patients were included in the statistical analysis (prilocaine group n=44, chloroprocaine group n=54). There were no significant differences in anthropometric data nor in surgery duration time (26.99 ± 7.96 min, mean ± SD). Statistical analysis showed significant differences between the groups regarding the primary outcome. 48.1% of patients in the chloroprocaine group were ambulatory at 2 hours compared to 4.5% in the prilocaine group (p<0.0001). Moreover, significant differences were observed in the percentage of ambulation at 2.5 hours (75.9% vs. 13.6%) and at 3 hours (94.4% vs. 31.8%) in favour of the 1% chloroprocaine group (p<0.0001). We observed a longer delayed discharge time in the chloroprocaine group (108.8 ± 55.5min vs. 45.3 ± 72.8 min) (p<0.0001), meaning patients in the chloroprocaine group remained longer in the hospital once discharge criteria were met. However, no differences were observed in the total length of hospital stay, likely due to administrative management issues. No major complications were recorded.
Conclusion: Spinal anesthesia with 1% chloroprocaine was found to be a good alternative for outpatient inguinal hernia repair, due to the rapid recovery of motor block and onset of ambulation of patients compared to 2% hyperbaric prilocaine, especially in afternoon surgery. In addition, it offers advantages to patients with COPD, difficult airway, or less airway manipulation, as in COVID-19.