Table 2:
Anesthesia and procedural characteristics prior to censoring*
| Characteristics | Regional Anesthesia (N=137) |
General Anesthesia (N=915) |
|---|---|---|
| Anesthesia duration, minutes | 146 [108, 179] | 151 [88, 210] |
| Type of Anesthesia | ||
| General | -- | 791 (86%) |
| Combined (general and regional) | -- | 124 (14%) |
| Peripheral nerve block | 72 (53%) | -- |
| Central neuraxial block | 65 (47%) | -- |
| Type of procedure | ||
| General | 5 (4%) | 169 (18%) |
| Orthopedic | 123 (90%) | 231 (25%) |
| Obstetrics/gynecology/urological | 5 (4%) | 126 (14%) |
| Cardiac with bypass | 0 (0%) | 48 (5%) |
| Neurosurgery | 0 (0%) | 50 (5%)† |
| Vascular | 1 (1%) | 33 (4%) |
| Thoracic | 0 (0%) | 24 (3%) |
| Breast/plastic | 0 (0%) | 33 (4%) |
| Otorynolaryngology/oral surgery | 0 (0%) | 58 (6%) |
| Other | 3 (2%) | 142 (16%) |
| Unknown | 0 (0%) | 1 (<1%) |
| Intravenous agents† | ||
| Sodium thiopental | 0 (0%) | 136 (15%) |
| Propofol | 117 (85%) | 774 (85%) |
| Adjuvant opioids | 130 (95%) | 841 (92%) |
| Ketamine | 8 (6%) | 40 (4%) |
| Benzodiazepines | 125 (91%) | 395 (43%) |
| Inhalational agents and nitrous oxide† | ||
| Any volatile anesthetic | NA | 756 (83%) |
| Isoflurane | NA | 392 (43%) |
| Sevoflurane | NA | 172 (19%) |
| Desflurane | NA | 285 (31%) |
| Nitrous oxide | 1 (1%)‡ | 401 (44%) |
Values are n (%) for categorical variables and median [Q1, Q3] for continuous variables. Overall, 648 patients underwent 1,052 procedures prior to censoring (n=341, 113, and 83 patients with 1, 2, and 3 or more general anesthetics respectively and n=89, 18, and 4 patients with 1, 2, and 3 or more regional anesthetics respectively). Combined general with regional anesthesia was classified as general anesthesia. Censoring occurred at the time of last z-score or the time of last z-score prior to occurrence of the patient’s exposure to a second type (regional or general) of anesthesia. Differences between the anesthetic agents used for GA and the type of local anesthetic agents or block location (peripheral vs central) for RA were not assessed in any regression analyses.
Since patients may have received multiple agents, the sum of the number of agents across categories does not equal to the total number of anesthetics.
This patient received N2O via mask due to resolving block by the end of operation.