Skip to main content

Table 1 Hemodynamic and patient variables from isoflurane-anesthetized horses (n = 5) breathing 50% or maximal oxygen concentrations

From: Effect of 50% and maximal inspired oxygen concentrations on respiratory variables in isoflurane-anesthetized horses

Parameter FiO2 -5 min 15 min 30 min 60 min 90 min 120 min 150 min 180 min +10 min Stand + 30 min
HR (beats/min) 50% 35 ± 2 32 ± 1 39 ± 2 40 ± 3 46 ± 3 43 ± 2 39 ± 3 39 ± 3 38 ± 4 38 ± 2
  >95% 42 ± 6 35 ± 3 37 ± 3 39 ± 5 39 ± 3 42 ± 3 41 ± 4 43 ± 4 34 ± 4 45 ± 5
RR (breaths/min) 50% 26 ± 3 6 ± 0a 5 ± 0a 5 ± 0a 4 ± 0a 4 ± 0a 4 ± 0a 4 ± 0a 12 ± 1a 20 ± 5
  >95% 27 ± 5 6 ± 0a 5 ± 0a 5 ± 0a 5 ± 0a 5 ± 0a 5 ± 0a 5 ± 0a 12 ± 4a 17 ± 2
PIP (cmH20) 50% ----- 29 ± 4 30 ± 3 31 ± 3 31 ± 3 32 ± 3 32 ± 3 33 ± 3 ----- -----
  >95% ----- 30 ± 4 29 ± 3 31 ± 2 32 ± 3 31 ± 3 32 ± 3 31 ± 3 ----- -----
EtCO2 (kPa) 50% ----- 4.18 ± 0.21 4.08 ± 0.13 4.18 ± 0.13 4.42 ± 0.18 4.21 ± 0.04 4.05 ± 0.10 3.97 ± 0.11 ----- -----
  >95% ----- 3.92 ± 0.33 4.32 ± 0.30 4.47 ± 0. 62 4.34 ± 0.12 4.21 ± 0.09 4.03 ± 0.12 3.82 ± 0.12 ----- -----
SABP (mmHg) 50% 143 ± 9 109 ± 6a 88 ± 5a 107 ± 4a 106 ± 3a 105 ± 2a 100 ± 1a 104 ± 2a 128 ± 5 176 ± 8a
  >95% 147 ± 7 106 ± 8a 95 ± 4a 103 ± 6a 103 ± 7a 104 ± 6a 105 ± 4a 102 ± 5a 129 ± 7 172 ± 10
MABP (mmHg) 50% 110 ± 3 82 ± 5a 66 ± 4a 80 ± 2a 85 ± 1a 84 ± 2a 84 ± 3a 85 ± 1a 109 ± 4 138 ± 7a
  >95% 112 ± 6 82 ± 9a 69 ± 3a 79 ± 5a 80 ± 4a 81 ± 4a 84 ± 4a 82 ± 2a 106 ± 4 136 ± 6a
DABP (mmHg) 50% 87 ± 5 69 ± 4 54 ± 3a 68 ± 2 72 ± 3 73 ± 3 71 ± 4 76 ± 2 96 ± 3 123 ± 11a
  >95% 93 ± 6 69 ± 8 58 ± 4a 66 ± 4a 67 ± 3a 72 ± 4 73 ± 4 70 ± 3 97 ± 4 115 ± 6
MRAP (mmHg) 50% 14 ± 3 6 ± 2 9 ± 1 10 ± 2 9 ± 2 12 ± 1 12 ± 1 13 ± 2 24 ± 1 15 ± 3
  >95% 13 ± 2 10 ± 2 13 ± 1 12 ± 2 11 ± 2 12 ± 3 14 ± 3 14 ± 3 21 ± 4 14 ± 3
MPAP (mmHg) 50% 30 ± 4 14 ± 1 17 ± 0 20 ± 2 23 ± 2 24 ± 3 24 ± 2 23 ± 2 36 ± 2 32 ± 3
  >95% 31 ± 2 21 ± 5 23 ± 4 26 ± 5 26 ± 5 26 ± 5 26 ± 5 26 ± 5 34 ± 5 34 ± 4
Q (L/min) 50% 34.2 ± 5.6 25.4 ± 2.8 28.1 ± 3.4 31.5 ± 2.8 32.9 ± 3.8 25.2 ± 3.3 23.3 ± 2.4 22.7 ± 1.5 19.9 ± 1.4 36.5 ± 3.6
  >95% 34.2 ± 3.6 22.5 ± 1.1 24.2 ± 1.5 30.1 ± 1.9 26.1 ± 3.6 25.2 ± 3.1 21.1 ± 0.9 21.3 ± 0.9 21.8 ± 1.5 40.2 ± 3.9
CI (L/kg bwt/min) 50% 0.056 ± 0.010 0.041 ± 0.004 0.045 ± 0.005 0.051 ± 0.005 0.053 ± 0.005 0.041 ± 0.005 0.038 ± 0.004 0.037 ± 0.0002 0.032 ± 0.002 0.059 ± 0.006
  >95% 0.056 ± 0.005 0.037 ± 0.001 0.040 ± 0.003 0.049 ± 0.003 0.043 ± 0.006 0.041 ± 0.005 0.035 ± 0.001 0.035 ± 0.001 0.036 ± 0.002 0.066 ± 0.007
SVR (dyn sec cm-5) 50% 248 ± 33 249 ± 34 172 ± 23 182 ± 13 195 ± 21 245 ± 33 258 ± 26 261 ± 22 347 ± 17 282 ± 36
  >95% 234 ± 13 256 ± 26 190 ± 25 182 ± 15 227 ± 35 227 ± 21 268 ± 14 256 ± 13 318 ± 24 251 ± 22
  1. Data are presented as mean ± standard error of the mean. HR, heart rate; RR, respiratory rate; PIP, peak inspiratory pressure; EtCO2, end-tidal CO2; SABP, systolic arterial blood pressure; MABP, mean arterial blood pressure; DABP, diastolic arterial blood pressure; MRAP, mean right atrial pressure; MPAP, mean pulmonary artery pressure; Q, cardiac output; CI, cardiac index; SVR, systemic vascular resistance. Time points: -5, 15, 30, 60, 90, 120, 150, and 180 represent min prior to and after induction of anesthesia; +10 min represents 10 min after disconnection from the anesthesia machine; and Stand +30 min represents 30 min after the horses stood in recovery.
  2. a Within a treatment, value is significantly different than the -5 min value for this variable.