Can a surgeon be negligent in continuing with an operation when there is bleeding in the retrobulbar?

In the case of Snell v. Farrell the trial judge found that the eye surgeon was negligent in continuing with the operation when there is bleeding other than the obvious pinprick of the needle. While the subsequent atrophy of the eye could have been caused by a number of causes one possible cause was pressure due to retrobulbar haemorrhage. By continuing the operation which was found by the trial judge to constitute negligence, the appellant made it impossible for the respondent or anyone else to detect the bleeding. In those circumstances it was open to the trial judge to draw the inference that the injury was caused by the retrobulbar bleeding.