Do Obese Patients without Cardiac History Show Worse Outcome after Pulmonary Artery Thrombectomy than Normal Weighted Patients?

Objectives: It is well-known that adipose patients undergoing extracorporal circulation show a different risk profile for mortality and morbidity than normal weighted patients.

Patients suffering from acute pulmonary embolism are mostly without former cardiac anamnesis. Therefore we initiated a clinical retrospective survey to research the influence of adiposity on the outcome after extracorporal circulation.

Methods: A 10 years retrospective study was performed including 125 patients (w/m:60/65) that underwent emergency pulmonary thrombectomy. Patients were assigned to either the Obese (n = 54, BMI ≥ 30) or the Control group (n = 71, BMI < 30). The Obese group included 13% of patients older than 75 years, in the Control group were 18.3% elderly patients (p = 0.104). Preoperative CPR until extracorporal circulation was needed in 11.1% of Obese and 7.0% of Control group (p = 0.115). Beating heart procedure underwent 48.1% in Obese and 46.9% in Control group. Extracorporal circulation time was > 120 minutes in 9.3% of Obese and 14.1% of Control group (p = 0.098).

Group differences were statistically tested by student‘s t-test.

Results: 30-day-Mortality was 16.7% (9/54) in Obese and 8.5% (6/71) in Control group (p = 0.005*).

From 6 preoperative reanimated patients 2 patients survived during in hospital stay in the Obese group (33.3%) and from 5 reanimated normal weighted patients four ones could be discharged (80%).

Two Obese patients got IABP for postoperative low cardiac output therapy and 8 patients in Control group (p = 0.001*). 5 obese patients and 2 normal weighted patients needed postoperative an ECLS (p = 0.002*). Further extracorporal circulation for longer cardiac reperfusion was used in 3 patients of Obese and in 7 patients of Control group (p = 0.009*).

Postoperative need of hemofiltration was detected in 9.2% of Obese and 5.6% of Control patients (p = 0.124). Ventilation time was shorter than 24 hours in 38.8% of Obese and in 53.5% of Control group (p = 0.111). Elongated ventilation time (>95 hours) was in 16.6% of Obese and 14.1% of Control group (p = 0.001*).

Conclusion: The data clearly show the negative influence of BMI on operative results of surgery of pulmonary artery embolism (PAE). As this can be explained by the application of ECC per se, other factors have to be considered such as sufficient ventilation and practical reanimation. In conclusion obese PAE-patients require aggressive treatment.