The former captain has flown home with an abductor problem he suffered during the first Test in Antigua, where New Zealand suffered a comprehensive nine-wicket defeat.
Vettori failed to have much of an impact after leapfrogging Stephen Fleming to become the Black Caps' most capped Test cricketer in 112th appearance for his country, scoring 30 runs in two innings and taking one for 124 in 51 overs.
The complaint could also rule him out of New Zealand's next Test assignment against India, which gets under way on August 23 in Hyderabad.
And batsman McCullum is aware the hole left by the left-arm spinner, who has 360 wickets in five-day cricket to his name, will be difficult to fill.
"It's a huge loss, not just the performance on the field which he's done for a number of years consistently and really led us from that point of view, but also what he offers in the changing room and when we're out on the field," said McCullum.
"You know you've got that experience to call on for some of the younger bowlers. He's had a phenomenal career and we hope he rests up and gets himself recuperated and comes back in a couple of months' time for us and we're able to get him back into a team that's performing a bit better than we have of late."
Tarun Nethula could make his Test debut today but a first-class average of just over 15 with the bat will cause concern for the balance of New Zealand's side, with Vettori nearly doubling that in his career.
The West Indies will hope to take advantage of the 33 year old's absence and Sunil Narine feels the side are champing at the bit to seal a success in the two-match series.
The spin bowler took eight wickets in Antigua in just his second Test to earn the man-of-the-match award, despite Chris Gayle scoring 150 and 64 not out and Kemar Roach setting up victory on the final day with a brilliant display of fast bowling that saw him claim five for 60.
Narine, 24, said the Windies are not content to rest on their laurels, though, as they look for their first Test series win since they beat England in 2009.
"We're pumped up. We are really ready for the Test match here at Sabina. As a matter of fact, we were ready from the start of the series," he added.
"We did a great job in Antigua and we celebrated our achievements. We have now put that behind us and all eyes are set on the second Test."
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