Fig. 3

The graph depicts the individual courses of mean arterial blood pressure in very low birth weight infants during open inguinal hernia repair. Each character represents a single patient. The surgical procedure started at the time point 0 min. For easier interpretation of the data a blue line was drawn at 35 mmHg, since this value marked the threshold that was defined to be safe according to Rhondali et al. [8] a The graph visualizes that in the group of combined general- and caudal anesthesia approximately half of the mean blood pressure values measured during inguinal hernia repair were below the critical threshold of 35 mmHg. b In contrast to the patients in the group of combined general- and caudal anesthesia only 3% of all mean blood pressure values measured in the caudal anesthesia group underran the critical margin of 35 mmHg