emergency surgery immediately after spay in a female dog

one female dog was operated through linea alba approach under isoflurane gas anesthesia. surgery went very well. dog was recovering from anesthesia. but suddenly the dog started collapsing and the blood loss was noticed by the team. immediately the effect of sedative was reversed by administering the antidote and the dog was put on other injectable anaesthetic drug. the site was opened for exploratory laprotomy and the bleeding was checked. though it was not a major bleeder but the blood loss was quite high, so the blood from abdominal cavity was collected in blood bag and blood transfusion was done to save the loss. the dog recovered very well and next day she was happy and active. she will stay for one more week and will be released after the perfect healing.