Background: Moebius sequence is a rare congenital absence of the sixth and seventh cranial nerves, although there may be additional congenital cranial neuropathies. Developmental delay, cardiac and musculoskeletal abnormalities may also coexist. Oro-facial manifestations include bilateral facial nerve palsy resulting in a mask like facies, drooling, incomplete eye closure, and strabismus secondary to the extra-ocular muscle imbalance. This condition has multiple implications for anesthetic care. Methods:We reviewed 111 anesthesia records of 46 patients with Moebius sequence for anesthesia technique and related complications.Results: Facial nerve palsy was universally present and bilateral in 44 (93.6%) patients. Thirty-two (68%) had concomitant sixth nerve palsy. Oro-facial and limb abnormalities were present in 16 (35%) and 18 (39%) of patients respectively. Endotracheal intubation, when attempted, was easy in 76 of 106 cases. Tracheal intubation was consistently difficult in seven patients and intubation failure occurred in a single patient only. Statistically significant factors associated with difficult tracheal intubation included structural abnormalities of the mandible and palate and abnormalities of four cranial nerves (IX, X, XI, XII). Conclusion:We confirm that tracheal intubation may be difficult in patients with Moebius sequence. We identify disease features that might predict a difficult tracheal intubation and thus allow the anesthesiologist an opportunity to plan accordingly.

HRC 101 significantly decreased sickle-related mortality during exposure to acute hypoxic stress in transgenic mice expressing hemoglobin SAD. HRC 101 warrants further evaluation as a therapeutic modality in sickle cell disease.

INTRODUCTION: Red cell transfusion decreases morbidity in sickle cell disease (SCD), but is not without risk. Utilization of a hemoglobin-based oxygen carrier (HBOC) could offer the benefits of red cell transfusion while reducing transfusion-related complications. We studied the effect of a novel HBOC, HRC 101, on survival during acute hypoxia in a murine model of SCD, the transgenic mouse expressing hemoglobin SAD. METHODS: After approval from the Animal Care Committee, 66 pathogen-free wild-type (n = 30) and transgenic SAD mice (n = 36) aged 6 -13 weeks and weighing 17 -31g were assigned at random to receive 0.02 ml/g body weight HRC 101 or an equal volume of 5% albumin administered via a 26-G catheter over 2 min into a tail vein. Following fluid administration, the animals were placed in a custom built Plexiglas chamber and observed for 20 min while breathing room air. Anesthesia was induced with halothane in 30% oxygen using a calibrated vaporizer and a continuous fresh gas flow rate of 5 l/min. Lead II of the electrocardiogram was monitored using needle electrodes and data acquisition software (AcqKnowledge version 3, MP100 Work Station, Harvard Apparatus). During halothane anesthesia (0.5% inspired concentration) and spontaneous ventilation, either 30% or 6% oxygen was administered. Heart rate, inspired concentrations of oxygen and halothane, and rectal temperature were recorded every 5 min. Time to cessation of cardiac electrical activity was recorded. At the time of death (cessation of cardiac electrical activity) or at the end of 1 h, blood was sampled via cardiac puncture for determination of blood gases and lactate concentration. Kaplan-Meier analysis with the log-rank test was used to compare survival rates. Two-way repeated measures or one-way ANOVA and the Student-Newman-Keuls post hoc test were used for statistical comparisons as appropriate. P < 0.05 was considered significant. RESULTS: In control groups, all mice survived the 60-min study period, whether breathing 30% or 6% oxygen. In contrast, all SAD mice administered albumin and 6% oxygen died, with a median survival time of 9.0 min (interquartile range, 6.9 -11.6 min) (P < 0.0001). Administration of HRC 101 significantly increased median survival time in SAD mice breathing 6% oxygen (figure). Of twelve SAD mice administered HRC 101 and 6% oxygen, four survived the entire study period and eight died, with a median survival time of 48 min (19 -60 min) (P < 0.0001 vs. albumin).