Table 1.
Characteristics of SpO2-SaO2 pairs recorded in study population, by race and ethnic origin
| Characteristics | Non-Hispanic white | Non-Hispanic black | Hispanic/ Latino |
P value of difference | |
|---|---|---|---|---|---|
| White v black | White v Hispanic | ||||
| Paired SpO2-SaO2 readings | |||||
| Total No | 21 918 | 6498 | 1623 | — | — |
| Median (IQR) pulse oximetry (SpO2, %) | 95 (93-97) | 97 (94-99) | 97 (94-99) | <0.001 | <0.001 |
| Median (IQR) arterial oxygen saturation (SaO2, %) | 94 (89.9-96.6) | 94.3 (89-97.1) | 95 (90.2-98) | 0.31 | <0.001 |
| Supplemental oxygen (L/min) | |||||
| Median (IQR) | 0 | 0 | 0 | <0.001 | 0.14 |
| Mean (SD) | 0.9 (2.5) | 0.6 (2.0) | 0.8 (2.7) | <0.001 | 0.14 |
| Potential occult hypoxemia | |||||
| All SpO2 (92-100%) | 18 157 (82.8) | 5852 (90.1) | 1466 (90.3) | <0.001 | <0.001 |
| SaO2 <88% if SpO2 is 92-100% | 2823 (15.6) | 1144 (19.6) | 237 (16.2) | <0.001 | 0.53 |
| Patient day characteristics | |||||
| Total No | 20 822 | 6190 | 1519 | ||
| Median (IQR) age (years) | 69 (64-77) | 66 (60-72) | 68 (62-76) | <0.001 | <0.001 |
| Male sex (No (%)) | 20 099 (96.5) | 5852 (94.5) | 1479 (97.4) | <0.001 | 0.082 |
| Primary diagnoses (No (%)) | |||||
| Chronic obstructive pulmonary disease | 2984 (14.3) | 681 (11.0) | 97 (6.4) | <0.001 | <0.001 |
| Respiratory failure | 2766 (13.3) | 633 (10.2) | 162 (10.7) | <0.001 | 0.003 |
| Septicemia | 1622 (7.8) | 466 (7.5) | 118 (7.8) | 0.50 | 0.98 |
| Pneumonia | 1608 (7.72) | 291 (4.7) | 59 (3.9) | <0.001 | <0.001 |
| Congestive heart failure | 1336 (6.4) | 464 (7.5) | 84 (5.5) | 0.003 | 0.17 |
| Coronary atherosclerosis | 391 (1.9) | 108 (1.7) | 184 (12.1) | 0.50 | <0.001 |
| Diabetes with complication | 309 (1.5) | 204 (3.3) | 30 (2.0) | <0.001 | 0.13 |
| Cardiac dysrhythmia | 361 (1.7) | 94 (1.5) | 18 (1.2) | 0.25 | 0.11 |
| Renal failure | 316 (1.5) | 115 (1.9) | 23 (1.5) | 0.06 | 0.99 |
| Acute myocardial infarction | 223 (1.1) | 58 (0.9) | 71 (4.7) | 0.36 | <0.001 |
| Other | 8906 (42.8) | 3076 (49.7) | 673 (44.3) | <0.001 | 0.24 |
| Comorbidities* (No (%)) | |||||
| Congestive heart failure | 7304 (35.1) | 2202 (35.6) | 486 (32.0) | 0.47 | 0.02 |
| Neurological disease | 2436 (11.7) | 896 (14.5) | 175 (11.5) | <0.001 | 0.834 |
| Chronic pulmonary disease | 11 911 (57.2) | 2642 (42.7) | 495 (32.6) | <0.001 | <0.001 |
| Liver disease | 1746 (8.4) | 694 (11.2) | 213 (14.0) | <0.001 | <0.001 |
| Diabetes without complication | 5099 (24.5) | 1732 (28.0) | 448 (29.5) | <0.001 | <0.001 |
| Diabetes with complication | 3480 (16.7) | 1171 (18.9) | 359 (23.6) | <0.001 | <0.001 |
| Non-metastatic cancer | 2176 (10.5) | 711 (11.5) | 146 (9.6) | 0.02 | 0.30 |
| Metastatic cancer | 782 (3.8) | 266 (4.3) | 38 (2.5) | 0.05 | 0.01 |
| Renal disease | 4935 (23.7) | 2004 (32.4) | 447 (29.4) | <0.001 | <0.001 |
| Median (IQR) length of hospital stay (days) | 6 (4-10) | 6 (3-11) | 9 (4-17) | <0.001 | <0.001 |
| Mortality (No (%)) | |||||
| In hospital | 1118 (5.4) | 350 (5.7) | 91 (6.0) | 0.39 | 0.30 |
| At 30 days | 2240 (10.8) | 553 (8.9) | 142 (9.4) | <0.001 | 0.086 |
SaO2=arterial blood gas reading; SpO2=pulse oximetry reading; IQR=interquartile range; SD=standard deviation.