Table II.
Cardiovascular, respiratory, and oxygen flow rates, blood gas, and desflurane variablesa
| Parameter | Group | Awake | 15 min | 30 min | 45 min | 60 min | 75 min | 90 min | 105 min | 165 min |
|---|---|---|---|---|---|---|---|---|---|---|
| HR | Xylazine | 43 ± 6 | 39 ± 3 | 37 ± 3 | 37 ± 4 | 40 ± 8 | 44 ± 11 | 46 ± 9 | 47 ± 8 | 41 ± 1 (2) |
| (beats/min) | Control | 38 ± 7 | 37 ± 5 | 39 ± 8 | 38 ± 6 | 41 ± 8 | 46 ± 11 | 48 ± 13 | 47 ± 15 | 39 ± 12 (3) |
| SABP | Xylazine | — | 103 ± 8 | 92 ± 9 | 91 ± 7 | 97 ± 8 | 103 ± 13 | 107 ± 17 | 105 ± 8 | 80 ± 7 (2) |
| (mmHg) | Control | — | 107 ± 19 | 89 ± 12 | 93 ± 7 | 99 ± 9 | 99 ± 6 | 95 ± 12 | 98 ± 8 | 100 ± 17 (3) |
| DABP | Xylazine | — | 63 ± 5 | 53 ± 7 | 51 ± 4 | 58 ± 6 | 65 ± 12 | 71 ± 13 | 68 ± 12 | 53 ± 11 (2) |
| (mmHg) | Control | — | 65 ± 12 | 50 ± 7 | 54 ± 7 | 59 ± 5 | 64 ± 6 | 63 ± 11 | 65 ± 5 | 67 ± 9 (3) |
| MABP | Xylazine | — | 78 ± 6 | 66 ± 8 | 66 ± 5 | 72 ± 8 | 79 ± 13 | 88 ± 11 | 83 ± 9 | 62 ± 9 (2) |
| (mmHg) | Control | — | 81 ± 15 | 63 ± 9 | 67 ± 6 | 73 ± 5 | 76 ± 6 | 74 ± 12 | 76 ± 6 | 79 ± 11 (3) |
| pH | Xylazine | — | 7.28 ± 0.04 | — | 7.45 ± 0.04 | — | — | — | 7.45 ± 0.04 | 7.44 ± 0.06 (4) |
| Control | — | 7.28 ± 0.04 | — | 7.43 ± 0.03 | — | — | — | 7.45 ± 0.03 | 7.46 ± 0.04 (4) | |
| PaO2 | Xylazine | — | 125 ± 57 | — | 228 ± 136 | — | — | — | 213 ± 105 | 135 ± 140 (4) |
| (mmHg) | Control | — | 160 ± 92 | — | 236 ± 170 | — | — | — | 220 ± 178 | 148 ± 129 (4) |
| PaCO2 | Xylazine | — | 67.4 ± 7.7 | — | 42.6 ± 1.1 | — | — | — | 42.6 ± 2.9 | 42.2 ± 1.4 (4) |
| (mmHg) | Control | — | 65.2 ± 6.5 | — | 44.1 ± 1.7 | — | — | — | 41.2 ± 2.5 | 40.4 ± 2.1 (4) |
| Vap | Xylazine | — | 10.2 ± 1.0 | 10.5 ± 1.2 | 10.8 ± 2.4 | 10.3 ± 2.1 | 10.3 ±1.9 | 10.8 ± 1.3 | 11.3 ±0.8 | 8.5 ± 0.7 (2) |
| (%) | Control | — | 9.8 ± 1.3 | 10.7 ± 1.0 | 10.0 ± 1.4 | 10.7 ± 1.5 | 10.5 ± 1.5 | 11.0 ± 0.9 | 11.0 ± 1.7 | 10.0 ± 1.7 (3) |
| O2 flow | Xylazine | — | 2.4 ± 0.5 | 2.2 ± 0.3 | 2.0 ± 0.2 | 2.0 ± 0.2 | 1.9 ± 0.2 | 1.9 ± 0.2 | 1.9 ± 0.2 | 1.9 ± 0.2 (2) |
| (L/min) | Control | — | 2.3 ± 0.4 | 3.7 ± 2.4 | 2.7 ± 1.2 | 2.4 ± 1.3 | 2.3 ± 1.1 | 2.3 ± 1.1 | 2.3 ± 1.1 | 1.8 ± 0 (3) |
| EtDES | Xylazine | — | 8.4 ± 1.1 (5) | 8.2 ± 1.0 (5) | 8.6 ± 1.1 (5) | 8.9 ± 1.1 (5) | 8.9 ± 0.9 (5) | 9.2 ± 0.5 (5) | 9.6 ± 0.5 (5) | 10.5 ± 0 (1) |
| (%) | Control | — | 7.9 ± 1.4 (4) | 8.3 ± 1.0 (4) | 8.8 ± 0.9 (4) | 9.0 ± 1.0 (4) | 9.3 ± 0.7 (4) | 9.6 ± 0.6 (4) | 10.0 ± 0.7 (4) | 12.8 ± 0 (1) |
Data are presented as mean ± standard deviation.
HR — heart rate; SABP — systolic arterial blood pressure; DABP — diastolic arterial blood pressure; MABP — mean arterial blood pressure; PaO2 — partial pressure of arterial oxygen; PaCO2 — partial pressure of arterial carbon dioxide; Vap — vaporizer setting; EtDES — end-tidal desflurane concentration.
a
Six horses were used, except where number of horses is in parentheses (for time point 165 min and EtDES concentrations).
Data for EtDES and time point 165 minutes are presented, but not analyzed due to insufficient numbers.