Sodium Bicarbonate for the prevention of contrast induced nephropathy in patients suspected with acute pulmonary embolism undergoing CTPA.

Contrast Induced Nephropathy (CIN) is a decrease in renal function following administration of radiographic contrast agents (defined as an increase in serum creatinine > 25% of > 44 umol). Patients with chronic renal impairment and diabetes are at high risk for CIN. To prevent CIN high risk patients receive hydration prior and post to contrast administration. However, when a patient is suspected of an acute pulmonary embolism (PE) there is no time for a hydration protocol with saline 12 hours prior to CTPA. Since the dosage of contrastmedia nessecary for CTPA is low and the contrastmedia are administered intravenously, the risk for CIN is low and hydration might not be nessecary.
Sodium bicarbonate has proven to be effective in preventing CIN when it is giving 1 hour prior and 6 hours after contrast administration.

The aim of our study is to analyse the mean increase in serum creatinine and the incidence of CIN following CTPA without prehydration compaired to a short prehydration regime with sodium bicarbonate during one hour. Furthermore, the risk of developing CIN after CT-PA with iso-osmolair contrast media is studied for both groups.

1. H0= Placebo is inferior to sodium bicarbonate in the prevention of contrast induced nephropathy in patients undergoing CTPA;

2. H1=Placebo is noninferior to sodium bicarbonate in the prevention of contrast induced nephropathy in patients undergoing CTPA.

1. 2 hours after CTPA;

2. 3 days (+/- 1 day) after CTPA;

3. 2 months after to CTPA when contrast induced nephropathy has been diagnosed.

1. Sodium Bicarbonate 1 hour prior to CTPA 1 ml/kg bodyweight;

2. CTPA without any hydration.