Comparison of Hemodynamic and Oxygen Transport Effects of Dopamine and Dobutamine in Critically Ill Surgical Patients: Results

Analysis of Data
Differences in control values of the series as a whole, as well as diagnostic related groups, and values at the optimal dose of dobutamine were evaluated by Students f-test for paired distributions. Changes at each dosage were evaluated by ANOVA and the Newman-Keuls test.
Results
Analysis of the Series as a Whole

Hemodynamic and oxygen transport data at the pretrial control period, at each dosage level, and at a post-trial control period for dopamine and dobutamine are compared in Table 2. Figures 1 to 3 compare changes from their pretrial baseline values that occurred at each dosage level for the two agents. There were marked and significant increases in Cl, LCW, Do2, and HR, as well as reduced SVRI, as measured by ANOVA after administration of dobutamine. There were similar changes after dopamine that were not statistically significant by ANOVA; however, there were significant reductions in Pa02 and significantly increased Pv02 and Qsp after dopamine (Table 2). The increases in HR, Cl, and flow-related variables were somewhat greater after comparable dosages of dobutamine. Although Pa02 decreased after dopamine, this resulted in minimal changes in saturation, but significantly increased Qsp. Oxygen delivery, which is calculated as the product of Cl and Ca02, increased after administration of each drug in proportion to the increased flow. Dobutamine significantly increased Vo2 (Fig 3). The differences between the pretrial baseline measurements of dobutamine and dopamine were not appreciable nor statistically significant; the differences between the pretrial and posttrial measurements of both drugs were also insignificant and inappreciable. read

Data in the Immediate Postoperative Period
The data from 16 patients studied in the immediate postoperative period were analyzed separately in Table 3. There were marked and significant increases in HR, Cl, SI, Do2, and Vo2 after dobutamine administration in this subset of patients. The maximal Cl response to dobutamine regardless of dosage was 1.99 ±0.65 (SD) L/min/sq m, while the maximal response to dopamine was 0.95 ±0.29 L/min/sq m (p<0.01). The maximal response of Vo2 to dobutamine was 55 ±41 ml/min/ sq m, while the maximal response of Vo2 to dopamine was 29 ±28 ml/min/sq m.
Table 2—Comparison of Hemodynamic and Oxygen Transport Effects of Dopamine and Dobutamine in the Entire Series

Drug and Variable PretrialBaseline Dosages jig/kg/min Post-trialBaseline
2.5 5.0 7.5 10
Dopamine
No. of subjects 25 25 20 18 15 19
MAP, mm Hg 92 ±17 92 ±18 93± 15 95± 15 93± 16 91 ±15
HR, beats per min 102 ±20 110 ±20 112 ±22 113 ±23 112 ±20 103 ±19
MPAP, mm Hg 23±8 23±8 23±6 21 ±7 23±6 23±8
PAWP, mm Hg 13 ±7 13 ±7 12 ±6 12 ±6 13 ±7 14 ±7
Cl, L/min/sq m 3.56 ±1.46 3.89 ± 1.45 4.15 ± 1.40 4.38 ±1.60 4.27±1.85 3.37 ±1.40
SI, ml/sq m 35.3 ±13.1 35.9± 12.6 38.0 ±12.6 40.0 ±15.2 39.2 ±17.4 33.3 ±13.2
LVSW, g*m/sq m 45.2 ±22.6 45.8 ±21.9 48.1 ±19.1 51.3 ±22.7 50.5±28.6 42.3 ±20.8
LCW, kg*m/sq m 4.5±2.4 5.0±2.4 5.3±2.1 5.7 ±2.5 5.5±2.9 4.2±2.1
SVRI, dyne*s/cm/sq m 1,950 ±586 1,761 ±519 1,684 ±510 1,654 ±484 1,662 ±509 2,066 ±609
PVRI, dyne*s/cm/sq m 233 ±150 232 ±115 214 ±111 184 ±79 211 ±105 250 ±171
Pa02, mm Hg 132 ±42 119 ±34 118 ±32 103 ±28 92±22t 130 ±42
Pv02, mm Hg 39 ±5 40±4 42±5 42±4t 40±4 38±4
Doa, ml/min/sq m 518 ±210 569 ±211 6Q3±207 630 ±232 611 ±254 502 ±191
Vo2, ml/min/sq m 136 ±35 138 ±33 147 ±46 143 ±48 136 ±33 138 ±33
Oxygen extraction, percent 28.2±7.6 26.5 ±7.0 25 3 ±6.2 23.8±5.9 23.9±5.5 29.1 ±6.4
Qsp, percent 14.5 ±9.0 17.0±9.6 16.7 ±8.7 21.1 ±10.6 24.0 ± 9.3t 12.9±6.7
Dobutamine
No. of subjects 25 25 25 24 20 20
MAP, mm Hg 93± 15 97 ±17 94± 16 94± 14 92± 14 90± 15
HR, beats per min 102 ±17 106 ±16 112 ±16 121 ±161: 126 ±17$ 106 ±19
MPAP, mm Hg 24±7 24±7 24±9 22±7 21 ±7 23±8
PAWP, mm Hg 15 ±6 15 ±6 14 ±6 12 ±5 11 ±5t 14 ±7
Cl, L/min/sq m 3.41 ±1.34 3.97 ±1.36 4.17± J..41 4.81±1.74t 4.79±1.38f 3.65± 1.38
SI, ml/sq m 33.6± 11.9 37.5 ±10.7 37.3± 11.6 40.2 ±13.5 37.8 ±8.5 34.4± 11.7
LVSW, g*m/sq m 43.3 ±18.9 50.0 ±18.4 48.1 ±19.3 52.1 ±21.2 47.6 ±15.5 42.7 ± 17.5
LCW, kg*m/sq m 4.4±2.0 5.3±2.2 5.4 ±2.3 6.2±2.7t 6.1±2.3 4.5±2.0
SVRI, dyne*s/cm/sq m 2,080 ±677 1,864 ±526 1,666 ± 498§ 1,467 ± 358§ 1,433 ±317§ 1,831 ±508
PVRI, dyne*s/cm/sq m 237 ±165 199 ±128 194 ±101 178 ±110 172 ±79 214 ±160
PaOs, mm Hg 125 ±37 121 ±38 121 ±38 115±41 112 ±42 126 ±43
PvQ2, mm Hg 38±5 39 ±4 39 ±5 40±5 41 ±7 39 ±5
Do,, ml/min/sq m 493 ±186 573 ±192 599 ±194 690± 248§ 693 ± 225§ 513 ±207
Vot, ml/min/sq m 139 ±40 147 ±43 151 ±38 161± 33t 158 ±49 133 ±30
Oxygen extraction, percent 29.8±7.2 26.6 ±5.3 26.4 ±6.9 24.9 ±6.2 24.0±7.2 27.8 ±7.2
Qsp, percent 13.1 ±6.3 14.5±6.9 15.1 ±6.7 16.8 ±7.3 19.1 ±10.5 15.1 ±9.3

Table 3—Comparison of Effects of Dopamine and Dobutamine in the Immediate Postoperative Period

Drug and Variable Baseline Dosage, p-g/kg/min
2.5 5 7.5 10
Dopamine
No. of subjects 13 13 11 9 7
MAP, mm Hg 92 ±13 98± 17 99± 14 97 ±14 99 ± 12t
HR, beats per min 104 ±22 113 ±20 117 ±22 116 ±27 112±21
MPAP, mm Hg 21 ±7 22 ±6 23±6 23±5 25±5
PAWP, mm Hg 13 ±5 13 ±6 13 ±6 14 ±7 14 ±7
Cl, L/min/sq m 3.31 ±1.07 3.72± 1.24 3.89± 1.15 3.89 ± 1.36 3.67 ±1.08
SI, ml/sq m 31 ±7 32 ±9 32 ±8 32 ±8 31 ±7
Do2, ml/min/sq m 467 ±177 522 ±200 540 ±198 527 ±223 472 ±104
Vo2, ml/min/sq m 130 ±33 140 ±42 153 ±51 133 ±57 121 ±36
Dobutamine
No. of subjects 13 13 13 13 12
MAP, mm Hg 98 ±14 103 ±13 99± 12 98± 10 95 ±11
HR, beats per min 105 ±15 110± 15 116 ±18 124 ±16f 127 ±18
MPAP, mm Hg 24 ±6 24±8 24±7 23±7 22±7
PAWP, mm Hg 15 ±6 14 ±6 14 ±5 12 ±5 ll±5t
Cl, L/min/sq m 3.12± 1.13 3.78 ±1.40 4.00±1.16t 4.41 ± 1.14f 4.55 ± 1.301*
SI, ml/sq m 28±8 34±7 34±8 36±7 36±7
Do2, ml/min/sq m 442 ±171 545 ±183 590 ±191 640 ± 1911 641 ±229
Vo2, ml/min/sq m 131 ±34 152 ±51 153 ±40 168 ± 39t 166 ±59

 

Figure 1. Changes in hemodynamic variables from baseline control values. Means (±SE) are shown for MAP, HR, Cl, SI, and LVSW, in response to dopamine (solid lines) and dobutamine (dashed lines) in dosages of 2.5μg/kg/min, 5μg/kg/min, 7.5μg/kg/min, and 10μg/ kg/m in.

Figure 1. Changes in hemodynamic variables from baseline control values. Means (±SE) are shown for MAP, HR, Cl, SI, and LVSW, in response to dopamine (solid lines) and dobutamine (dashed lines) in dosages of 2.5μg/kg/min, 5μg/kg/min, 7.5μg/kg/min, and 10μg/ kg/m in.

Figure 2. Changes in mean pulmonary arterial pressure. PAWP, SVRI, and PVRI, in response to dopamine (solid lines) and dobutamine (dashed lines) at various dosages.

Figure 2. Changes in mean pulmonary arterial pressure. PAWP, SVRI, and PVRI, in response to dopamine (solid lines) and dobutamine (dashed lines) at various dosages.

Figure 3. Changes in oxygen transport variables, PaOz, PvOa, Do2, Vo2, oxygen extraction, and Qsp, in response to dopamine (solid lines) and dobutamine (dashed lines) at various dosages.

Figure 3. Changes in oxygen transport variables, PaOz, PvOa, Do2, Vo2, oxygen extraction, and Qsp, in response to dopamine (solid lines) and dobutamine (dashed lines) at various dosages.

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