Table 2.
Clinical characteristics of intensive care unit (ICU) patients with pandemic influenza A (H1N1pdm09) virus infection
| Characteristics | Children <18 years (n = 46) | Adults ≥18 years (n = 108) | Total (n = 154) |
|---|---|---|---|
| Clinical signs at admission, no. (%) | |||
| Tachypnea | 32/42 (76) | 45/101 (45) | 77/143 (54) |
| Tachycardia | 39/42 (93) | 77/103 (75) | 116/145 (80) |
| Hypotension (MAP < 60) | 4/38 (11) | 10/105 (10) | 14/143 (10) |
| Illness onset to hospitalization, median (IQR),* day | 2 (1–5) (n = 44) | 3 (2–5) (n = 108) | 3 (2–5) (n = 152) |
| Admission ≤ 2 days after illness onset, no. (%) | 24/44 (55) | 37/108 (34) | 61/152 (40) |
| Length of hospital stay, median (IQR), day | 6 (3–13) (n = 45) | 9 (4–18) (n = 107) | 8 (4–16) (n = 152) |
| ICU length of stay, median (IQR), day | 3 (2–12) (n = 34) | 5 (2–11) (n = 80) | 4 (2–11) (n = 114) |
| Any underlying medical condition,** no. (%) | 28 (61) | 72 (67) | 100 (65) |
| Asthma | 12 (26) | 25 (23) | 37 (24) |
| Chronic obstructive pulmonary disease | 0 (0) | 18 (17) | 18 (12) |
| Neurological disease | 14 (30) | 12 (11) | 26 (17) |
| Diabetes | 0 (0) | 22 (20) | 22 (14) |
| Cardiac disease | 2 (4) | 21 (19) | 23 (15) |
| Immunosupression | 6 (13) | 11 (10) | 17 (11) |
| Renal disease | 1 (2) | 11 (10) | 12 (8) |
| Pregnancy | 0 (0) | 11 (10) | 11 (7) |
| Obesity,*** no. (%) | 6/20 (30) | 23/78 (29) | 29/98 (30) |
| Morbid obesity,*** no. (%) | NA | 21/78 (27) | 21/98 (21) |
| Radiographic evidence of pneumonia at admission, no. (%) | 28/41 (68) | 73/101 (72) | 101/142 (71) |
| Treatment with influenza antivirals, no. (%) | 38 (83) | 90 (83) | 128 (83) |
| ≤2 days after illness onset | 14/37 (38) | 22/88 (25) | 36/125 (29) |
| 3–5 days after illness onset | 11/37 (30) | 34/88 (39) | 45/125 (36) |
| ≥6 days after illness onset | 12/37 (32) | 32/88 (36) | 44/125 (35) |
| Antibiotic treatment, no. (%) | 41 (89) | 103 (95) | 144 (94) |
| Steroids, no. (%) | 26 (57) | 43 (40) | 69 (45) |
| Mechanical ventilation, no. (%) | 23 (50) | 66 (61) | 89 (58) |
| Sepsis syndrome, no. (%) | 9/39 (23) | 27/91 (30) | 36/130 (28) |
| Acute respiratory distress syndrome, no. (%) | 10/38 (26) | 38/90 (42) | 48/128 (38) |
| Death, no. (%) | 9 (20) | 28 (26) | 37 (24) |
*Interquartile range.
**Patients who are pregnant, immunocompromised (either because of medications or immune disorders including human immunodeficiency syndrome), or have chronic pulmonary (including asthma or chronic obstructive pulmonary disease), cardiovascular (excludes hypertension), renal, hepatic, hematological, neurological, or metabolic disease (including diabetes) are considered at high‐risk for influenza‐related complications.
***Obesity and morbid obesity are mutually exclusive.