Table 1.
Characteristics of the Study Populationa
| All Patients (n = 7,851) | |
|---|---|
| Demographics | |
| Age – median years (quartiles) | 72 (59 – 81) |
| Sex (female) – no. (%) | 3,298 (42) |
| Race – no. (%) | |
| White | 5,573 (74) |
| Black | 1,695 (22) |
| Other | 277 (4) |
| Type of Admission – no. (%) | |
| Medical – non-cardiac | 3,963 (51) |
| Medical – cardiac | 2,437 (31) |
| Surgical – non-cardiac | 1,029 (13) |
| Surgical – cardiac | 323 (4) |
| Trauma | 94 (1) |
| Pre-existing Conditions – no. (%) | |
| Cardiac | |
| Arrhythmia | 2,412 (31) |
| History of MI | 1,246 (16) |
| MI this admission | 877 (11) |
| History of heart failure | 1,852 (24) |
| Heart failure this admission | 1,540 (20) |
| Non-Cardiac | |
| Respiratory insufficiency | 2,407 (31) |
| Diabetes mellitus | 2,762 (35) |
| Renal insufficiency | 2,635 (34) |
| Metastatic/hematologic malignancy | 1,206 (15) |
| Hypotension/hypoperfusion | 1,042 (13) |
| Pneumonia | 1,162 (15) |
| Baseline depression in CNS function | 848 (11) |
| Metabolic/electrolyte abnormality | 922 (12) |
| Septicemia | 1,010 (13) |
| Acute CNS non-stroke event | 504 (6) |
| Hepatic insufficiency | 497 (6) |
| Acute stroke | 312 (4) |
| Major trauma | 160 (2) |
| Arrest Characteristics – no. (%) | |
| Location | |
| Floor without telemetry | 3,735 (48) |
| Floor with telemetry | 4,116 (52) |
| Time of day (night [11:00pm – 6:59am]) | 2,746 (35) |
| Time of week (Friday 11pm to Monday 7am) | 2,473 (32) |
| Hospital wide cardiac arrest response activated | 7,576 (97) |
| Monitored | 5,618 (72) |
| Witnessed | 4,980 (63) |
| First rhythm shockable (VT or VF) | 1,208 (16) |
a
MI indicates myocardial infarction, CNS: central nervous system, VT: ventricular tachycardia, and VF: ventricular fibrillation