Effects of a single bolus of urokinase in patients with life-threatening pulmonary emboli: a descriptive trial.

Abstract

To evaluate hemodynamic, angiographic, and biological effects of a single bolus of urokinase, an open descriptive trial was conducted in a homogeneous group of 14 patients with acute life-threatening pulmonary emboli and without prior cardiopulmonary disease. For every patient the efficacy of the treatment was evaluated by comparing control and posttherapeutic values after the bolus injection of 15,000 IU/kg body weight urokinase (urinary source) administered in 10 min in the right atrium, followed by continuous intravenous full-dose heparin therapy. In two patients clinical status, hemodynamics, vascular obstruction, and biological (fibrinogen and plasminogen levels) parameters remained unchanged. One of these two patients died, making the mortality rate for the whole group 7%. Twelve of 14 patients showed rapid clinical improvement. Evaluation at 12 hr demonstrated significant decreases in pulmonary vascular obstruction (Miller index, 34%), total pulmonary vascular resistances (37%), and fibrinogen and plasminogen levels (41% and 40%, respectively), without any significant change in cardiac index. The hemodynamic sequential measurements performed (1, 3, 6, and 12 hr) in seven of the 12 improved patients showed that the greatest percentage of the total hemodynamic improvement occurred within the first 3 hr after bolus administration of urokinase. No severe hemorrhagic complications were observed. Because of its rapid efficacy and its low cost, the bolus technique appeared particularly useful in the treatment of patients with acute life-threatening pulmonary emboli.Circulation 70, No. 5, 861-866, 1984. SEVERE, life-threatening pulmonary emboli associated with clinical shock, right ventricular failure, seizures, or syncope require early, rapid, and effective therapy.Under

The presence of shock defines the threshold to initiate thrombolytic therapy in patients with pulmonary embolism

“…Ostensibly, the putative benefits of thrombolytic therapy derive from the enhanced rapidity of embolic resolution thereby diminishing the RV wall stress and/or the potential to minimize or thrombolyse the residual thrombotic burden in the periphery, thereby minimizing or preventing recurrent PE. The shape of the PE PVR curve is hyperbolic, with a dramatic increase in PVR at a threshold obstruction of approximately 60% [28]. The relatively modest diminution (12%) in obstruction seen on perfusion scans 2 h after thrombolytic therapy [45] results in a substantial decrease in PVR in patients with a high PVR or significant degree of obstruction.…”

“…Second, because RV dilatation begins to occur with 30% obstruction of the pulmonary vasculature, the majority of PE patients have RV dilatation as reported in various clinical series [12,25]. The relationship between the pulmonary vascular resistance (PVR) and the degree of anatomic obstruction is hyperbolic and not linear, with a dramatic rise in PVR when obstruction exceeds 60% [28]. This accounts for the observation that CO is characteristically elevated in most PE patients without prior CPD, and that depressions in CO are unusual until the obstruction exceeds 50%[23].…”

Comparative Tolerability Profiles of Thrombolytic Agents

“…d Dickie et al (1974); Petitpretz et al (1984); Stern et al (1988). e Luomanmaki et al (1983); Ly et al (1978); Miller et al (1971); Ohayon et al (1986); Tibbutt et al (1974).…”

Pulmonary Embolism. II. Diagnosis and Treatment

“…No significant hemodynamic and angiographic differences after 12 hours could be found. 140 Recent interest has focused on the bolus injection of a weight-adjusted dose of rt-PA 153,154 or UK 155 in the treatment of patients with PE intending to increase both efficacy and safety. Bolus infusion of 15,000 to 20,000 IU/ kg of UK has been shown to be effective in producing a rapid decline in pulmonary hypertension and pulmonary vascular obstruction and was associated with a low bleeding rate.…”