The effect of low flow anesthesia on hemodynamic and peripheral oxygenation parameters in obesity surgery

Article Figures & Data

Table 1

- Demographic data.

Demographic data	High-flow n=17	Low-flow n=27	P-value
Age	38±11	35±8	0.484
Gender (M/F)	8/9	6/21	0.089
Height	166±8	164±9	0.438
Weight	134±19	126±20	0.154
Body mass index	47±6	46±5	0.856
Operation time	122±45	144±51	0.100
Extubation time	6.2±3.2	5.5±2.8	0.352
Recovery time	10.8±3.5	8.4±3.2	0.076
Hemoglobin (g/dl)	16.8±1.7	16.6±1.4	0.745

Table 2

- Analysis of vital signs.

Vital signs	Beginning	10^th min	30^th min	60^th min	Extubation	Postoperative
HR (beat/min)
High-flow	94 ± 13	96 ± 11	89 ± 13	84 ± 12	78 ± 19	84 ± 15
Low-flow	91 ± 17	86 ± 15	80 ± 15	84 ± 15	82 ± 14	79 ± 13
P-value	0.366	0.035	0.074	0.772	0.499	0.188
SAP (mm Hg)
High-flow	156 ± 21	136 ± 51	117 ± 17	124 ± 25	141 ± 36	139 ± 26
Low-flow	142 ± 21	125 ± 30	114 ± 23	119 ± 20	129 ± 21	130 ± 19
P-value	0.089	0.419	0.772	0.426	0.242	0.098
DAP (mm Hg)
High-flow	94 ± 18	73 ± 17	68 ± 15	80 ± 23	81 ± 21	81 ± 20
Low-flow	85 ± 17	74 ± 21	68 ± 18	74 ± 14	78 ± 17	76 ± 17
P-value	0.151	0.781	0.894	0.267	0.587	0.267
MAP (mm Hg)
High-flow	117 ± 19	92 ± 18	86 ± 13	93 ± 17	99 ± 24	102 ± 20
Low-flow	110 ± 16	92 ± 3	85 ± 20	92 ± 16	98 ± 18	98 ± 16
P-value	0.252		0.990	0.655	0.952	0.347
SPO2 (%)
High-flow	95 ± 3	97 ± 3	98 ± 2	96 ± 4	94 ± 3	96 ± 5
Low-flow	95 ± 4	97 ± 4	98 ± 2	98 ± 2	95 ± 3	97 ± 3
P-value	0.496	0.835	0.639	0.669	0.133	0.370
EtCO2 (mm Hg)
High-flow	36 ± 7	34 ± 4	34 ± 3	38 ± 4	36 ± 4	36 ± 5
Low-flow	35 ± 7	34 ± 4	37 ± 5	38 ± 5	35 ± 2	37 ± 5
P-value	0.838	0.904	0.173	0.913	0.405	0.673

SpO₂: peripheral oxygen saturation, HR: heart rate, SAP: full meaning, MAP: full meaning, EtCO2: end-tidal carbon dioxide

Table 3

- Arterial blood gas analysis.

Arterial blood gas analysis	Beginning	10^th min	30^th min	60^th min	Extubation
PO₂ (mm Hg)
High-flow	98 ± 18	100 ± 20	103 ± 13	110 ± 9	104 ± 34
Low-flow	94 ± 25	101 ± 20	102 ± 19	112 ± 14	101 ± 25
P-value	0.440	0.914	0.563	0.942	0.933
PCO₂ (mm Hg)
High-flow	35 ± 4	39 ± 4	40 ± 4	41 ± 3	43 ± 6
Low-flow	36 ± 5	36 ± 5	39 ± 5	41 ± 3	40 ± 5
P-value	0.716	0.039	0.252	0.923	0.064
SaO₂ (%)
High-flow	98 ± 3	96 ± 3	96 ± 4	97 ± 1	96 ± 4
Low-flow	97 ± 3	95 ± 4	96 ± 3	97 ± 2	96 ± 2
P-value	0.344	0.715	0.875	0.725	0.961
HCO₃ (mmol/L)
High-flow	23.7 ± 1.2	20.7 ± 1.5	20.4 ± 1.9	20.1 ± 1.0	20.1 ± 1.1
Low-flow	20.7 ± 1.6	20.5 ± 2.7	20.3 ± 1.9	20.3 ± 1.6	21.0 ± 1.8
P-value	0.328	0.962	0.971	0.718	0.106
BE (mmol/l) (base excess)
High-flow	2.3 ± 1.4	3.9 ± 1.7	5.1 ± 1.3	5.0 ± 1.2	4.9 ± 1.5
Low-flow	2.2 ± 1.6	3.9 ± 2.1	4.6 ± 2.0	4.7 ± 1.7	4.3 ± 2.1
P-value	0.563	0.923	0.455	0.214	0.341
PH
High-flow	7.39 ± 0.05	7.36 ± 0.06	7.34 ± 0.06	7.32 ± 0.05	4.9 ± 1.5
Low-flow	7.39 ± 0.06	7.36 ± 0.07	7.36 ± 0.06	7.31 ± 0.06	4.3 ± 2.1
P-value	0.990	0.971	0.524	0.731	0.138
Lactate (mmol/L)
High-flow	0.7 ± 0.3	0.9 ± 0.4	1.1 ± 0.6	1.3 ± 0.8	1.0 ± 0.3
Low-flow	0.7 ± 0.3	0.9 ± 0.4	1.3 ± 0.6	1.4 ± 0.8	1.0 ± 0.3
P-value	0.971	0.990	0.317	0.857	0.971

PO₂: oxygen saturation, PCO₂: pressure of carbon dioxide, SaO₂: oxygen saturation, HCO₃: Bicarbonate, BE: fbase excess, PH: arterial hydrogen ion concentration