Histamine Applied Topically to the Nasal Mucosa Increases the Transmucosal Nitrous Oxide Exchange for the Middle Ear.

OBJECTIVE: Determine if the middle ear transmucosal nitrous oxide (N2O) exchange rate is affected by nasal inflammation caused by topical application of histamine. METHODS: In a randomized, double-blind, crossover study, 20 adults were challenged intranasally with histamine (5 mg) and placebo on separate occasions. At each session, the subjects were fitted with a non-rebreathing mask and breathed room air for 20 minutes, 50% N2O:50% O2 for 20 minutes, and 100% O2 for 10 minutes. Throughout, heart rate, blood pressure, and blood O2 saturation were monitored, and bilateral middle ear pressure was recorded by tympanometry every minute. The primary outcome measure was the slope of the middle ear pressure-time function for the 50% N2O:50% O2 breathing period, which is a measure of the transmucosal N2O exchange-constant. The effects of challenge substance, session, and period on the measured vital signs and of treatment, session, ear disease history, and test ear on the pressure-time slopes were evaluated using repeated measures ANOVAs. RESULTS: The post-challenge total symptom score and the slope of the middle ear pressure-time function were greater after histamine when compared to placebo challenge. Of the signs, only heart rate was affected, responding to challenge substance and study period. CONCLUSION: The transmucosal N2O exchange rate for the middle ear is increased during inflammation caused by nasal histamine exposure.

Measurement, Standards, and Peer Benchmarking: One Hospital's Journey.

Peer-to-peer benchmarking is an important component of rapid-cycle performance improvement in patient safety and quality-improvement efforts. Institutions should carefully examine critical success factors before engagement in peer-to-peer benchmarking in order to maximize growth and change opportunities. Solutions for Patient Safety has proven to be a high-yield engagement for Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, with measureable improvement in both organizational process and culture.

Oxymetazoline Applied Topically to the Nasal Mucosa Decreases Trans-Mucosal Nitrous Oxide Exchange for the Middle Ear.

OBJECTIVE: Determine if the middle ear (ME) trans-mucosal nitrous oxide (N2O) gas exchange rate can be pharmacologically modulated by the nasal application of a vasoconstrictor. METHODS: In a randomized, double-blind, crossover study, 20 adults received a nasal spray challenge containing either oxymetazoline or saline (placebo). At each session, subjects were fitted with a non-rebreathing mask and breathed room air for 20 minutes, 50% N2O:50% O2 for 20 minutes, and 100% O2 for 10 minutes. Throughout, heart rate, blood pressure (BP), and blood O2 saturation were monitored, and bilateral ME pressure was recorded by tympanometry every minute. The primary outcome measure was the slope of the ME pressure-time function for the experimental period, a direct measure of the transMEM N2O exchange constant. The effects of treatment, session, and period on the measured vital signs and of treatment, session, disease history, and ear on the ME pressure-time slopes were evaluated for statistical significance using repeated measures ANOVAs. RESULTS: The analysis documented a significant effect of period on O2 saturation (N2O > room air, P = .03) and of treatment on blood pressure (oxymetazoline > placebo, P < .02) and the ME pressure-time slope (placebo > oxymetazoline, P = .05). CONCLUSION: The exchange rate across the ME mucosa of inert gases can be decreased by topical treatment of the nasal mucosa with oxymetazoline.

Oral pseudoephedrine decreases the rate of transmucosal nitrous oxide exchange for the middle ear.

OBJECTIVES/HYPOTHESIS: Determine if oral treatment with a vasoconstrictor decreases the blood to middle ear exchange rate of the perfusion-limited gas, nitrous oxide (N2O). STUDY DESIGN: Randomized, double-blind, crossover study. METHODS: Ten adult subjects with and 10 without past middle ear disease completed paired experimental sessions, identical except for oral treatment with either pseudoephedrine hydrochloride or lactose placebo. At each session, subjects were fitted with a nonrebreathing mask and breathed room air for 20 minutes (acclimation period), 50% N2O:50% O2 for 20 minutes (experimental period), and 100% O2 for 10 minutes (recovery period). Throughout, heart rate, blood pressure, and O2 saturation were monitored, and bilateral middle ear pressures were recorded by tympanometry every minute. The primary outcome was the slope of the middle ear pressure-time function for the experimental period, which estimates the volume N2O exchange rate. Using repeated measures analysis of variance, the effects of group (disease history), treatment (active vs. placebo), and period (1 vs. 2) on the recorded vital signs, and of group, treatment, and ear (left/right) on the middle ear pressure-time slope were evaluated for statistical significance. RESULTS: Statistically significant effects of period on O2 saturation (period 2 > period 1) and of treatment on heart rate (active > placebo) were documented. Only treatment was statistically significant for the middle ear pressure-time slope, with a shallower slope characterizing the active treatment session. CONCLUSIONS: The volume exchange rate across the middle ear mucosa of perfusion-limited gases can be modulated pharmacologically. Theoretically, similar drugs can be used to reduce the requisite eustachian tube opening efficiency for adequate middle ear pressure regulation. LEVEL OF EVIDENCE: 1b.

Is Canine Eruption Velocity Affected by the Presence of Allograft Within a Repaired Alveolar Cleft?

PURPOSE: To assess the rate of canine eruption in alveolar clefts repaired with cancellous autograft versus cancellous autograft mixed with allograft. MATERIALS AND METHODS: This was a retrospective cohort study of patients in mixed dentition who underwent primary repair of uni- or bilateral alveolar cleft defects. Patients were divided into 2 groups based on the method of bony reconstruction (group 1, iliac crest autograft; group 2, iliac crest autograft harvested through a minimal access approach and mixed 1:2 with demineralized bone allograft). Secondary predictor variables were demographic and anatomic factors potentially related to canine eruption. The outcome variable was the velocity of canine eruption, measured as the change in vertical distance from the incisal edge to the maxillary occlusal plane (millimeters per month). Descriptive, bivariate, and linear regression statistics were computed. RESULTS: The study sample included 57 alveolar cleft defects; 19 were repaired with autograft alone and 38 were repaired with autograft plus allograft. The sample's mean age was 9.9 ± 2.3 years at the time of repair. Thirty-one clefts (54.4%) were part of a bilateral deformity. Canine root formation was 50% complete at the time of surgery in most patients (59.6%). Mean duration of follow-up was 23.7 ± 13.2 months. Mean canine eruption velocity was 0.20 ± 0.18 mm per month and was not associated with the method of bony repair (P = .58). CONCLUSION: The use of allograft bone to augment bone graft volume results in similar rates of canine eruption compared with autograft bone alone.

Traumatic intrusion of maxillary permanent incisors into the nasal cavity associated with a seizure disorder: report of a case.

Childhood traumatic dental injury is typically associated with motor vehicle accidents, sports, or other recreational activities. However, seizure disorders or other compromising medical conditions may precipitate dental trauma. Complete intrusion injuries in the mixed or permanent dentition are relatively rare. This paper describes the case history of an adolescent male who sustained displacement of a lateral incisor into the nasal cavity and complete bony intrusion of the three other permanent maxillary incisors because of a fall following a seizure. Counseling on helmet/face-shield usage for seizure-susceptible patients must be provided and documented, particularly after sustaining traumatic injury.