Table 3.
Cardiorespiratory data from castrations performed in field conditions compared to hospital conditions with protocol ARBZ (acepromazine, romifidine, butorphanol and tiletamine/zolazepam)
| Variables | Protocol | n | Baseline | ANE 5' | ANE 15' | ANE 25' | ANE 35' | Post |
| HR | Hospital | n = 9 | 39 (3)* | 33 (5)B* | 32 (4)B* | 33 (6) B* | 34 (7)* | 33 (7)B* |
| Beats/min | Field | n = 31 | 44 (6) | 39 (6) | 41 (6) | 40 (5) | 40 (5) | 43 (10) |
| SAP mean | Hospital (invasive) | n = 9 | ND | 128 (20) | 126 (16) | 124 (22) | 110 (19) | 115 (22) |
| mm Hg | Field (non-invasive) | n = 6 | ND | 108 (16) | 114 (14) | 113 (21) | 114 (34) | ND |
| RR | Hospital | n = 9 | 18 (8) | 17 (6) | 19 (7) | 20 (7) | 19 (5) | 14 (3) |
| Breaths/min | Field | n = 31 | 15 (3) | 14 (6) | 19 (8) | 22 (7)B | 24 (7)B | 14 (6) |
| PaCO2 | Hospital | n = 9 | ND | 6.4 (0.5) | 6.1 (0.5) | 6.4 (0.3) | 6.3 (0.3) | 6.2 (0.4) |
| kPa | Field | n = 11 | ND | 6.7 (0.8) | 6.4 (0.6) | [6.1 (1.0)] (n = 4) | ND | ND |
| PaO2 | Hospital | n = 9 | ND | 8.3 (1.6) | 8.4 (1.9) | 7.5 (1.8) | 8.4 (2.0) | 13.5 (1.4) |
| kPa | Field | n = 11 | ND | 7.6 (0.8) | 8.1 (1.1) | [8.3 (0.7)] (n = 4) | ND | ND |
| PjvO2 | Hospital | n = 9 | ND | 5.0 (0.5) | 4.9 (0.4) | 4.8 (0.6) | 5.0 (0.4) | 5.3 (0.5) |
| kPa | Field | n = 9 | ND | 5.0 (0.5) | 5.1 (0.8) | [5.4 (0.6)] (n = 3) | ND | ND |
Data presented as mean (SD) for heart rate (HR), mean systemic arterial pressure (SAP mean), respiratory rate (RR), arterial carbon dioxide tension (PaCO2), arterial oxygen tension (PaO2), jugular venous oxygen tension (PjvO2). Baseline = measurements performed in the standing unsedated horse. ANE 5', 15', 25' and 35' = measurements at 5, 15, 25 and 35 minutes of anaesthesia. Post = 5 minutes after the horse had regained the standing position.* = Field conditions significantly different from hospital conditions. B = Significantly different from Baseline. ND = not determined. Values within brackets [] not included in statistical analysis.