Table 2 Randomized controlled trials with theophylline as a prophylactic measure to prevent contrast-induced nephropathy
Reference | Year | Number of patients | Reason for contrast administration | Study design | Dose/timing/route of administration of theophylline | Hydration regimen | Main outcomea |
|---|---|---|---|---|---|---|---|
[38] | 1994 | 39 | Various reasons | RCT: theophylline versus placebo | 5 mg/kg body weight iv, 45 min before contrast | 1000 ml/hour saline 0.9% NaCl iv, 4 hours before – 12 hours after contrast | GFR and CC ↓ in placebo (P < 0.01) |
[39] | 1995 | 93 | Various reasons | RCT: theophylline versus placebo; non-ionic, low-osmolality CM versus ionic, high-osmolality CM | 4 × 2.88 mg/kg body weight, po, start 1 hour before contrast | >1.43 ml/kg per hr dextrose 5% iv or po 24 hours before – 48 hours after contrast | Non-ionic, low-osmolar: CC ↓ 18 ± 4% in placebo versus 0% in theophylline group (P < 0.05) Ionic, high-osmolar: CC ↓ 42 ± 5% in placebo versus 24 ± 3% in theophylline group (P < 0.01) |
[40] | 1998 | 58 | Various reasons | RCT: theophylline versus placebo | 165 mg iv, placebo, 30 min before contrast | Not specified | GFR ↓ in placebo (P < 0.001) |
[41] | 1999 | 60 | Coronary angioplasty | RCT: theophylline versus dopamine versus placebo | 4 mg/kg iv, 1 hour, start 2 hours before contrast followed by 0.4 mg/kg per hour for 12 hours | 1 ml/kg per hour 0.45% saline iv 12 hours before – 12 hours after contrast | 35% versus 50% versus 30%; NS |
[42] | 1999 | 80 | Various reasons | RCT: theophylline versus placebo | 810 mg daily po, 2 days before – 3 days after contrast | 2000–2500 ml 0.45% saline iv or po 24 hours before – 24 hours after | 6% (2/35) versus 3% (1/29); NS |
[44] | 2002 | 100 | Various reasons | RCT: theophylline versus placebo | 200 mg iv, 30 min before contrast | Variable (>2000 ml was advised) | 4% versus 16%; P = 0.046 |
[45] | 2002 | 70 | Coronary angiography | RCT: theophylline versus placebo | 200 mg po, twice daily, 24 hours before – 48 hours after contrast | Not specified | 3% versus 31%; P = 0.004 |
[46] | 2003 | 100 | Coronary angiography | RCT: theophylline versus placebo | 200 mg iv, 30 min before contrast | Variable (>2000 ml was advised) | 4% versus 20%; P = 0.0138 |