Anesthetic Management of Treacher Collins Syndrome in an Outpatient Surgical Center.

BACKGROUND Treacher Collins syndrome is a rare autosomal dominant disorder characterized by micrognathia and abnormal development of the zygomatic arch, which may result in significant upper airway obstruction. As patients who have it age, their upper airway obstruction may worsen. Therefore, they typically require several surgeries throughout their lives to correct specific facial abnormalities. Anesthetic and airway management of patients with Treacher Collins syndrome can be challenging for anesthesia providers, especially in ambulatory settings. CASE REPORT A 15-year-old patient with Treacher Collins syndrome presented to our outpatient surgery center for midface fat grafting. He had undergone multiple surgical procedures at Nationwide Children's Hospital, which is affiliated with The Ohio State University Wexner Medical Center. A decision was made to proceed with the grafting surgery after: (1) the literature was thoroughly reviewed; (2) multidisciplinary planning had been done utilizing our comprehensive preoperative screening and assessment process; (3) the scope of care at our ambulatory surgery center, the patient's medical history, and relevant airway notes had been reviewed; (4) the case was discussed with the surgeon; and (5) relevant images of the patient had been gathered. Evaluation of the patient's airway on the day of surgery was reassuring and a plan for managing a potentially difficult airway had been developed. After anesthetic induction, mask ventilation without adjuvants was successful. Video and direct laryngoscopy (for purposes of education) revealed grade 1 views. Supraglottic airway device placement resulted in an effective seal and the remainder of the surgery and the patient's subsequent course were uneventful. CONCLUSIONS Improved airway approaches, combined with thorough preoperative screening and multidisciplinary planning and communication, may make it possible to perform ambulatory surgery on patients with Treacher Collins syndrome, whose condition typically represents a significant challenge to anesthesia providers.

Sex-specific effects of heme oxygenase-2 deficiency on renovascular hypertension.

BACKGROUND: Heme oxygenase-2 (HO-2) is the main isoform responsible for the breakdown of heme and release of carbon monoxide in the vasculature. Vascular-derived carbon monoxide protects against excessive vasoconstriction due to agents such as angiotensin II (Ang II) and in states of deficiency of nitric oxide. The current study was designed to determine the role of HO-2 in the development of renovascular hypertension using HO-2 knockout mice. METHODS: Polyurethane cuffs were placed around the left renal artery of male and female HO-2 wild-type (WT), heterozygous (HET), and knockout (KO) mice between 16 and 24 weeks of age to induce renovascular hypertension. After 3 weeks, blood pressure was measured for 5 days, after which time both clipped and unclipped kidneys were harvested. RESULTS: No differences were observed in the blood pressure of sham mice between the different genotypes of both sexes. Cuffing of the left renal artery resulted in a significant increase in blood pressure in all genotypes of both sexes. In male mice, the increase in blood pressure was significantly greater in HET and KO mice as compared to WT mice (P < .05). This effect was not observed in female mice. Renovascular hypertension resulted in a significant increase (P < .05) in cardiac hypertrophy in male mice, which was not different between the genotypes. In female mice, HET and KO mice exhibited significantly greater (P < .05) cardiac hypertrophy as compared with WT mice. CONCLUSION: These results demonstrate a sex-specific effect of HO-2 deficiency on the development of renovascular hypertension and its effects on the heart in response to the increase in blood pressure.

Antihypertensive actions of moderate hyperbilirubinemia: role of superoxide inhibition.

BACKGROUND: Moderate (approximately 2-fold) increases in plasma unconjugated bilirubin levels are able to attenuate the development of angiotensin II (Ang II)-dependent hypertension. To determine the specific role of decreases in superoxide production to the blood pressure-lowering effects of moderate hyperbilirubinemia (MHyB), we performed this study, in which the Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin was given to Ang II-infused mice in the presence and absence of moderate hyperbilirubinemia. METHODS: Apocynin (14mM) was administered in the drinking water prior to treatment with UDP-glucuronosyltransferase 1A1 antisense morpholino (16 µg/kg), which was administered by intravenous injection every third day. Treatments were started before the implantation of Ang II-containing minipumps (1µg/kg/min) and continued throughout the protocol. RESULTS: Ang II infusion increased blood pressure to 145±2mm Hg. Apocynin treatment alone reduced blood pressure to 135±5mm Hg, whereas MHyB alone decreased blood pressure to 118±5mm Hg in Ang II-infused mice. Prior inhibition of NADPH oxidase with apocynin did not result in a further decrease in blood pressure in MHyB mice, which averaged 117±3mm Hg (n = 6 mice per group). In aortic preparations, apocynin treatment decreased Ang II-mediated superoxide production from 2433±120 relative light units (RLU)/min/mg to 1851±126 RLU/min/mg (n = 4 mice per group), which was similar to levels observed in MHyB mice alone (1473±132 RLU/min/mg) or in combination with apocynin (1503±115 RLU/min/mg). CONCLUSIONS: Our results indicate that MHyB lowers blood pressure by a mechanism that is partially dependent on the inhibition of superoxide production.