Anesthesia Management

Introduction

Craniosynostosis surgery presents a unique set of challenges to the anesthesiology team caring for the patient, particularly when surgery is done on young infants. Amongst a number of potential problems and concerns, the two most prominent are extensive blood losses and venous air emboli (VAE). As each child is different and presents with unique characteristics and concerns, the preoperative assessment needs to be tailored to each individual patient. Airway evaluation and appraisal is essential, particularly in cases where craniofacial syndromes are present. The same applies to cardiac assessment in association with syndromes. Historically, treatment has evolved and nowadays, most craniofacial programs in large children’s hospitals perform the type of procedures commonly known as calvarial vault remodeling (CVR). These operations are extensive, invasive, traumatic in nature, and typically associated with large blood losses. For this type of procedure, baseline blood work needs to be collected preoperatively and should include hematological values, electrolytes, and coagulation studies. Given the concern for possible sudden large volume blood loss, blood products should be ordered and be available at time of induction. Craniosynostosis vault surgery is perhaps one of the only surgeries where the anesthesiology team gives the patient blood products prior to skin incision. This is particularly the case when the patient presents with low blood volumes and values. Careful monitoring of the patient during the surgery requires placement and insertion of arterial peripheral lines, a central venous line, multiple large bore intravenous lines, and Foley catheter.

With the introduction of minimally invasive endoscopic-assisted techniques in 1998, the overall anesthetic management of patients afflicted with craniosynostosis has evolved significantly. In this chapter we will present our team’s approach to the successful application of anesthetic management principles to minimally invasive craniosynostosis techniques.

Preoperative Evaluation and Assessment

A careful history is imperative to ascertain possible intraoperative risks and complications as well as to properly prepare for unexpected events. Salient points to consider include preterm versus term birth, congenital cardiac/pulmonary defects, history of increased intracranial pressure, and/or any other factors that required admission to the neonatal intensive care unit (NICU). The physical examination should be focused on the airway assessment, breath sounds, and cardiac examination. Patients with a history of heart murmur should have a cardiology consult and an echocardiogram performed prior to surgery. A final critical consideration is the physiologic anemia of the newborn. At the nadir of anemia, in full-term infants, hemoglobin levels may be as low as 9 to 10 g/100 mL at 6 weeks of age. Given the short anesthetic time and minimal blood losses associated with endoscopic craniosynostosis procedures, we do not routinely obtain extensive preoperative blood work but simply rely on a hemoglobin/hematocrit (H/H) level and a type and screen, which is obtained after the patient is induced under general anesthesia. We do not type and cross our patients as the need of a blood transfusion (postoperatively) has been very rare during the last 10 years.