A BREAKDOWN IN CREW COORD RESULTS IN A DEP OF AN ACR WITHOUT THE REQUIRED DISPATCHER APPROVAL OF AN MEL ITEM.

Narrative

AFTER LEAVING THE GATE FOR TKOF; GND NOTIFIED US OF A DELAY AND GAVE A WHEELS-UP TIME 15 MINS LATER. THE FO DECIDED TO USE THIS TIME TO SEND A DISCREPANCY MESSAGE TO OUR MAINT CTL CTR VIA ACARS. I HADN'T NOTICED SINCE I WAS CONSIDERING WHETHER TO SHUT AN ENG DOWN OR NOT; HOPING FOR A 5 MIN EARLY CLRNC. WE DID GET AN EARLY TKOF CLRNC AND WHILE PERFORMING MY PRE-TKOF CHK; NOTICED AN ACARS RESPONSE FROM MAINT CTL. MY NEXT THOUGHT WAS TO CHK THE MEL; BUT THE THROTTLES WERE UP BY THEN AND WE WERE XING THE HOLD LINE. THERE WAS; ALSO; SOME PRESSURE TO EXPEDITE SINCE LNDG TFC WAS 3 MI OUT. I HAD CONSIDERED STOPPING; BUT WAS BEYOND THE HOLD LINE. ALSO; CANCELING CLRNC AND PULLING OFF AT NEXT INTXN; BUT LNDG TFC WAS CLOSING. SO; WE TOOK OFF; WITHOUT CONSULTING THE MEL. ONCE AIRBORNE; WE DID CHK; AND THE MEL REQUIRED DISPATCHER'S APPROVAL. IT WAS TOO LATE. I SPOKE WITH FO ABOUT CREW COORD AND TELLING THE CAPT ABOUT ANY PROBS THAT HE OR THE FLT ATTENDANTS FIND; NO MATTER HOW SEEMINGLY SMALL. WE; ALSO; DISCUSSED DISPATCH DEFINITIONS FOR MEL PURPOSES. HE LEARNED SOMETHING THAT DAY.