High-flow nasal cannula oxygen therapy during anesthesia recovery for older orthopedic surgery patients: A prospective randomized controlled trial

Table 1 Preoperative baseline characteristics of the patients based on grouping

Characteristic	Conventional mask group (n = 30)	HFNCO group (n = 30)	P value
Age (yr)	72.8 ± 5.7	72.5 ± 4.3	0.778
Sex
Male	9 (30)	10 (33.3)	0.781
Female	21 (70)	20 (66.7)
Weight (kg)	62.4 ± 10.5	63.1 ± 8.0	0.756
BMI	25.1 ± 3.8	25.3 ± 3.5	0.793
ASA
II	15 (50)	21 (70)	0.114
III	15 (50)	9 (30)
Operation type			0.320
TKA	18 (60)	13 (43.3)
Spinal surgery	6 (20)	11 (36.7)
Others	6 (20)	6 (20)

Data are presented as mean ± SD or n (%). ASA: American Society of Anesthesiologists; BMI: Body mass index; HFNCO: High-flow nasal cannula oxygen; TKA: Total knee arthroplasty.

Table 2 Comparison between the conventional mask group and the high-flow nasal cannula oxygen group before the intervention

	Conventional mask group (n = 30)	HFNCO group (n = 30)	P value
Before anesthesia
HR	75.9 ± 11.4	74.7 ± 9.6	0.652
MAP	118.8 (109.0, 128.3)	119.8 (105.0, 126.6)	0.6521
SpO2	98.0 (97.0, 100.0)	99.0 (97.0, 100.0)	0.3211
pH	7.42 (7.40, 7.43)	7.42 (7.41, 7.44)	0.2611
paCO2	37.7 (75.4, 39.7)	38.9 (36.5, 40.6)	0.3291
paO2	78.9 (70.5, 85.3)	76.8 (70.0, 84.0)	0.9531
Glucose	5.5 (5.3, 6.6)	5.6 (5.3, 6.3)	0.9471
Lactic acid	1.3 (1.0, 1.8)	1.3 (1.1, 1.5)	0.6891
Extubation
HR	78.6 ± 11.8	73.9 ± 11.3	0.122
MAP	107.8 (102.3, 126.0)	110.5 (96.8, 117.5)	0.6631
SpO2	100.0 (99.0, 100.0)	100.0 (100.0, 100.0)	0.0401
pH	7.33 (7.30, 7.35)	7.33 (7.30, 7.37)	0.3671
paCO2	48.1 (43.6, 54.1)	48.0 (43.6, 54.7)	0.9761
paO2	75.1 (64.0, 86.3)	74.0 (67.2, 89.7)	0.7511
Glucose	6.2 (5.7, 7.5)	6.6 (5.4, 7.5)	0.9001
Lactic acid	1.8 (1.5, 2.2)	1.7 (1.3, 2.5)	0.9411

¹Mann-Whitney U test.

Data are presented as mean ± SD and median (interquartile spacing). HFNCO: High-flow nasal cannula oxygen; HR: Heart rate; MAP: Mean arterial pressure; paCO₂: Arterial partial pressure of carbon dioxide; paO₂: Arterial partial pressure of oxygen; SpO₂: Saturation of peripheral oxygen.

Table 3 Comparison between the conventional mask group and the high-flow nasal cannula oxygen group after the intervention

	Conventional mask group (n = 30)	HFNCO group (n = 30)	P value
5 min after extubation
HR	76.0 ± 12.8	71.3 ± 11.0	0.138
MAP	108.3 (99.0, 120.5)	105.5 (96.3, 115.1)	0.4731
SpO2	100.0 (97.8, 100.0)	100.0 (100.0, 100.0)	0.0321
15 min after extubation
HR	76.6 ± 12.7	71.4 ± 10.5	0.091
MAP	108.5 (96.0, 121.9)	105.3 (95.9, 118.6)	0.6201
SpO2	100.0 (98.0, 100.0)	100.0 (100.0, 100.0)	0.0011
30 min after extubation
HR	75.9 ± 13.1	70.3 ± 8.8	0.054
MAP	107.5 (97.0, 117.6)	111.0 (100.3, 117.8)	0.6731
SpO2	100.0 (98.8, 100.0)	100.0 (100.0, 100.0)	0.0021
1 h after extubation
HR	76.5 ± 13.6	71.0 ± 9.2	0.073
MAP	105.8 (97.3, 119.1)	107.5 (110.5, 121.0)	0.6471
SpO2	100.0 (99.0, 100.0)	100.0 (100.0, 100.0)	0.0031
pH	7.36 (7.34, 7.38)	7.36 (7.33, 7.37)	0.6521
paCO2	44.0 (40.1, 48.2)	45.3 (41.8, 49.8)	0.7061
paO2	114.0 (83.5, 147.6)	194.9 (162.9, 242.2)	< 0.0011
Glucose	8.3 (6.5 ,8.9)	7.6 (6.5, 8.7)	0.5691
Lactic acid	1.4 (1.1, 1.7)	1.4 (1.1, 1.8)	0.9411

¹Mann-Whitney U test.

Data are presented as mean ± SD and median (interquartile spacing). HFNCO: High-flow nasal cannula oxygen; HR: Heart rate; MAP: Mean arterial pressure; paCO₂: Arterial partial pressure of carbon dioxide; paO₂: Arterial partial pressure of oxygen; SpO₂: Saturation of peripheral oxygen.

Table 4 Postoperative evaluation of the patients in the conventional mask group and high-flow nasal cannula oxygen group

	Conventional mask group (n = 30), n (%)	HFNCO group (n = 30), n (%)	P value
Patients’ oxygen tolerance score			0.0781
1	29 (96.7)	30 (100)
2	0	0
3	1 (3.3)	0
4	0	0
5	0	0
Airway humidification			0.237
Yes	27 (90)	30 (100)
No	3 (10)	0

¹Fisher’s exact test.

Airway humidification evaluation: “yes” indicates satisfactory airway humidification; “no” indicates unsatisfactory airway humidification. Data are presented as n (%). HFNCO: High-flow nasal cannula oxygen.