Severalcomplicationsofinsertionanduseofpulmonaryarterycatheter(PAC),includingcatheterentrapment,arerecognizedduringoraftercardiacsurgery.Earlydetectionisveryimportant.WereportacaseofPACentrapmentbecausethethecatheterwasaccidentallysuturedtothesuperiorvenacava.Bleedingfromthethermistorconnectorwasinitiallydetectedaftersurgerybecausetheneedlepuncturedthelumenofthermistorconnector.ThePACwasremovedthroughre-exploration.Therefore,bleedingfromthethermistorconnectorcouldearlyindicatethePACentrapment.Wesuggestthatabnormalbleedingfromthenon-injectatelumenportsofPACshouldbecheckedbeforesternalclosure.