Intraoperative monitoring during vascular surgery

Monitoring During Vascular Surgery

Vascular surgical patients present unique challenges for anesthesiologists, because of their medical vulnerabilities as well as their tendency for rapid intraoperative hemodynamic changes. Intraoperative monitors have been used for decades to reduce adverse outcomes, improve mortality, and create optimal surgical conditions. Understanding the indications and appropriate management of monitoring modalities is essential for optimizing patient care, and preventing harm associated with misinterpretation. We aim to review monitoring technologies used in complex vascular procedures, as well as the current guidelines, clinical trial outcomes, and basic mechanisms of each monitoring modality.

Metabolic changes during major craniofacial surgery

OBJECTIVES

The purpose of this study was to document the degree and duration of perioperative metabolic disturbance during major craniofacial surgery in children.

AIM

The aim was to quantify the degree and duration of perioperative metabolic disturbance and to determine the relationship between the metabolic changes and the duration of surgery and total volume of blood and colloid given during surgery.

BACKGROUND

These patients have the potential for massive blood loss and significant metabolic acidosis. Routine perioperative monitoring includes the serial measurement of base deficit (BD) as a marker of metabolic disturbance.

METHODS/MATERIALS

All patients undergoing elective major craniofacial surgery were prospectively studied over a 10-month period. BD from arterial blood gas analysis was measured at standardized intervals during the perioperative period. The duration of surgery and total volume of blood and colloid given intraoperatively were used as covariates in a multiple regression analysis.

RESULTS

Maximum recorded BD ranged from -3 to -20 (median -9). Median time taken to return to normal was 9.25 h (range 0-18 h). Median duration of significant BD was 3.8 h (range 0-20 h).

CONCLUSIONS

Children undergoing major craniofacial surgery develop a varying degree of perioperative metabolic acidosis persisting for several hours. The maximum BD appears to be related to the amount of intraoperative blood loss and replacement rather than duration of surgery. As it is difficult to predict the extent and duration of metabolic acidosis for an individual patient, this study confirmed our current practice that all patients should be admitted to a neurosurgical high-dependency unit postoperatively for overnight monitoring.