Evaluation of narrow-band imaging in the diagnosis of sinonasal inverted papilloma

KEY POINTS

Narrow-band imaging (NBI) can be used to differentiate benign sinonasal lesions NBI can be used in the preoperative identification of sinonasal inverted papilloma Future studies can focus on NBI for recurrent inverted papilloma and surgical margin guidance.

Urgency of Esophageal Foreign Body Removal: Differentiation Between Coins and Button Cell Batteries

OBJECTIVE

Coin-shaped button battery foreign bodies have a similar initial presentation to coin ingestion, but delayed retrieval of a battery from the esophagus can have devastating consequences. Variations in timing of retrieval for children with ingestion of coin foreign bodies have been reported. The study assesses the sensitivity and specificity of conventional and digital radiographs to differentiate button batteries from coin foreign bodies.

STUDY DESIGN

3B case control study.

STUDY SETTING

Tertiary academic medical center.

METHODS

A radiographic study of the 12 most common commercially available button batteries and 66 coins of varying international origins was performed. Foreign bodies were placed at the cervical esophagus of a cadaver, and anteroposterior (AP) and lateral conventional radiographs of the neck were obtained. Digital AP and lateral radiographs of standalone coins and batteries were also obtained. Images were blindly read by 2 otolaryngologists and 2 radiologists. Statistical analysis was performed to determine accuracy in identifying coins vs batteries.

RESULTS

Using conventional radiographs to identify button batteries yielded a sensitivity of 0.88 and a specificity of 0.92 (positive predictive value [PPV] = 0.75, negative predictive value [NPV] = 0.97). Digital radiography yielded an overall sensitivity of 0.98 and specificity of 0.97 (PPV = 0.87, NPV = 0.99). Features of button batteries were only seen on AP conventional radiographs using reverse contrast.

CONCLUSIONS

Neither conventional nor digital radiographic imaging had perfect accuracy in identifying coins vs batteries. Features of common disc batteries were identified, which may aid in diagnosis. With potential devastating consequences from retained battery in the esophagus, emergent removal of any possible disc battery foreign body should be considered.

Objective sleep measures after endoscopic sinus surgery in patients with chronic rhinosinusitis

BACKGROUND

Poor sleep quality is common in chronic rhinosinusitis (CRS). Prior studies have demonstrated improvements in patient-reported measures of sleep quality following endoscopic sinus surgery (ESS). The purpose of this study was to evaluate the effect of ESS on objective sleep parameters and identify any associations between specific objective measures and patient characteristics, comorbidities, and patient-reported outcome measures (PROMs).

METHODS

Adults with CRS undergoing ESS were prospectively enrolled from 4 centers across North America. Any subject previously diagnosed with a known primary sleep disorder was excluded. Objective sleep indices were recorded using a portable sleep diagnostic device preoperatively and postoperatively. Patient-reported outcome instruments were completed including the Pittsburgh Sleep Quality Index (PSQI) and the 22-item Sino-Nasal Outcome Test (SNOT-22).

RESULTS

Thirty-six patients (mean age 47 years, 56% male) completed baseline and postoperative sleep studies with mean ± standard deviation (SD) follow-up 9.6 ± 7.7 months. Mean PSQI and SNOT-22 before and after ESS was 10.2 ± 3.9 vs 7.8 ± 4.4 (p = 0.001); and 54.6 ± 14.6 vs 28.5 ± 15.3 (p < 0.001), respectively. Total sleep time, sleep latency, and awakenings after sleep onset did not change following ESS (all p > 0.5) despite improvements in PSQI and SNOT-22. Changes in PSQI did not correlate with comorbidities or objective sleep indices (all p > 0.1).

CONCLUSION

In this multicenter prospective cohort, objective sleep indices were not improved following ESS for CRS despite significant improvements in patient-reported sleep quality and CRS-specific QOL.

Targeted Molecular Therapies in Allergy and Rhinology

Biologic agents, monoclonal antibodies that target highly-specific molecular pathways of inflammation, are becoming integrated into care pathways for multiple disorders that are relevant in otolaryngology and allergy. These conditions share common inflammatory mechanisms of so-called Type 2 inflammation with dysregulation of immunoglobulin E production and eosinophil and mast cell degranulation leading to tissue damage. Biologic agents are now available for the treatment of chronic rhinosinusitis with nasal polyps (CRSwNP), asthma, eosinophilic granulomatosis with polyangiitis (EGPA), atopic dermatitis (AD), and chronic spontaneous urticaria (CSU). This paper summarizes the diagnosis and management of these conditions and critically reviews the clinical trial data that has led to regulatory approval of biologic agents for these conditions.

Quality improvement in tracheostomy care: A multidisciplinary approach to standardizing tracheostomy care to reduce complications

PURPOSE

Develop a model for quality improvement in tracheostomy care and decrease tracheostomy-related complications.

METHODS

This study was a prospective quality improvement project at an academic tertiary care hospital. A multidisciplinary team was assembled to create institutional guidelines for clinical care during the pre-operative, intra-operative, and post-operative periods. Baseline data was compiled by retrospective chart review of 160 patients, and prospective tracking of select points over 8 months in 73 patients allowed for analysis of complications and clinical parameters.

RESULTS

Implementation of a quality improvement team was successful in creating guidelines, setting baseline parameters, and tracking data with run charts. Comparison of pre- and post-guideline data showed a trend toward decreased rate of major complications from 4.38% to 2.74% (p = 0.096). Variables including time to tracheotomy for prolonged intubation, surgical technique, day of first tracheostomy tube change, and specialty performing surgery did not show increased risk of complications. There were increased tracheostomy-related complications in cold months (p = 0.04).

CONCLUSIONS

An interdisciplinary quality improvement team can improve tracheostomy care by identifying system factors, standardizing care among specialties, and providing continuous monitoring of select data points.

Mobile app technology is associated with improved otolaryngology resident in-service performance

OBJECTIVE

Otolaryngology residents face time-management challenges between clinical duties and self-directed learning. Mobile devices provide a new medium for education that could aid with educational efficiency. The objective of this study was to investigate whether spaced repetition mobile app use of an otolaryngology question bank was associated with improving factual knowledge as measured by in-service exam performance.

METHODS

For approximately 6 months prior to the 2016 in-service examination, 12 otolaryngology residents at a single institution were provided access to a spaced-repetition app with a preloaded licensed otolaryngology review question bank. The number of questions answered, as well as the time spent on the app, were electronically tracked. The associations of app usage on in-service results were analyzed using an autoregressive model adjusted for prior historical Otolaryngology Trainee Examination performance and postgraduate year.

RESULTS

Eleven residents used the mobile app and were included in the analysis for an average of 304 minutes (range: 3 to 1,020) and reviewed on average 679 questions (range: 6 to 1,934). Controlling for residency year and prior performance, app usage was associated with an improvement by 2.92 percentage points (pp) (95% confidence interval [CI]: 0.14, 5.70) on overall in-service score. Allergy and pediatric subsection scores improved by 11.3 pp (95% CI: 3.8, 18.8) and 15.2 pp. (95% CI: 8.9, 21.5), respectively. Increased app use was associated with a score improvement by 0.008 pp per minute of use (95% CI: 0.004, 0.012).

CONCLUSION

Use of mobile spaced-repetition technology can aid resident factual knowledge retention measured by improved in-service exam performance.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:E15-E20, 2019.

Compliance With Subcutaneous Immunotherapy Appointments in an Urban Tertiary Care Setting

INTRODUCTION

Subcutaneous immunotherapy (SCIT) is an effective treatment for allergic disease such as allergic rhinitis and asthma. Reported adherence rates to SCIT have been low, ranging between 50% and 89%. This study sought to evaluate compliance to SCIT in an urban "safety net," tertiary care center, and to evaluate for disparities in compliance based upon insurance and socioeconomic status.

METHODS

A retrospective chart review of SCIT patients between 2003 and 2016 was performed. Demographic data, insurance carriers, and comorbidities were collected. Compliance was evaluated on treatment adherence (percentage of injections administered/scheduled appointments). Statistical analysis was performed using R statistical software. Linear regression analysis was performed to compare compliance to the variables, asthma, duration of therapy, payor, and age. Analysis of variance was used to compare mean compliance between payor groups.

RESULTS

Two hundred five patients met our inclusion criteria and 28 were excluded. Insurance composition was Medicaid (67, 33%), Medicare (18, 9%), Health Safety Net (HSN) in Massachusetts (33, 16%), and commercial payors (82, 42%). Linear regression demonstrated that age, duration of therapy, and asthma status were not related to the percentage of missed doses ( P > .05). Payor status was statistically predictive of missed doses ( P = .02). When comparing average percentage of missed immunotherapy shots, Medicaid patients missed the most 34.2%, followed by Medicare 24.4%, commercial insurance 19.9%, and HSN in Massachusetts 18.5% ( P ≤ .02).

CONCLUSION

In a cohort of patients at a tertiary care "safety-net" center serving a low-income population, compliance to SCIT was found to be overall high but lower in the Medicaid population.

Rational Approach to Allergy Testing

Allergy testing is commonly used when symptoms of allergic rhinitis are refractory to symptoms and there is potential for treatment with institution of avoidance measures or immunotherapy. Once the decision for testing has been made, the method of testing by either in vivo skin testing by prick/puncture or intradermal testing or in vitro testing of serum-specific IgE is dictated by factors in the clinical history and an informed decision by the patient. Because there is no perfect testing method, understanding the benefits and limitations of each method is important in selecting the best testing option for each patient.

Inhalant allergen sensitization is an independent risk factor for the development of angioedema

BACKGROUND/OBJECTIVE

The etiology and risk factors for angioedema remain poorly understood with causative triggers often going undiagnosed despite repeated reactions. The purpose of this study was to determine the relationship between inhalant allergen sensitization and angioedema.

METHODS

A retrospective review of patients who had in vitro inhalant allergy testing from 2006 to 2010 was performed. Patients with a diagnosis of angioedema who underwent inhalant allergy testing were identified. Analyses for co-morbidities, class of sensitization, seasonal timing of angioedema, and concurrent use of known hypertensive medications that can cause angioedema were performed.

RESULTS

There were 1000 patients who underwent inhalant allergy testing and qualified for the study. 37/1000 had at least one episode of angioedema and of these patients, 34 had positive inhalant sensitization testing results. Multivariate regression models showed overall sensitization status, seasonal allergen and epidermal/mite sensitization as independent risk factors (p<0.001, p=0.005, p=0.025 respectively) when controlling for ACE inhibitor use and other covariates. Tree, and epidermal/mite sensitizations were independent risk factors for angioedema in mono-sensitized subject analysis (p=0.028, p=0.029, respectively).

CONCLUSION

Both seasonal and perennial allergen sensitizations are independent risk factors for the development of angioedema. In patients with angioedema and an unknown trigger, inhalant allergen sensitization should be considered as a potential contributing factor to the development of angioedema.

Clinical Consensus Statement: Balloon Dilation of the Sinuses

Objective

To develop a clinical consensus statement on the use of sinus ostial dilation (SOD) of the paranasal sinuses.

Methods

An expert panel of otolaryngologists was assembled to represent general otolaryngology and relevant subspecialty societies. The target population is adults 18 years or older with chronic or recurrent rhinosinusitis (with or without nasal polyps, with or without prior sinus surgery) for whom SOD is being recommended, defined as endoscopic use of a balloon device to enlarge or open the outflow tracts of the maxillary, frontal, or sphenoid sinuses, as a standalone procedure or with endoscopic surgery. A modified Delphi method was used to distill expert opinion into clinical statements that met a standardized definition of consensus.

Results

After 3 iterative Delphi method surveys, 13 statements met the standardized definition of consensus while 45 statements did not. The clinical statements were grouped into 3 categories for presentation and discussion: (1) patient criteria, (2) perioperative considerations, and (3) outcomes. Strong consensus was obtained for not performing SOD in patients without sinonasal symptoms or positive findings on computed tomography (CT) in patients with symptoms only of headache or sleep apnea without criteria for sinusitis. In addition, strong consensus was met that CT scan of the sinuses was necessary before performing SOD and that surgeons need to understand and abide by regulations set forth by the US Food and Drug Administration if they choose to reuse/reprocess devices.

Conclusion

Expert panel consensus may provide helpful information for the otolaryngologist considering the use of SOD for the management of patients with a diagnosis of rhinosinusitis. This panel reached consensus on a number of statements that defined the use of SOD as inappropriate in the management of a variety of symptoms or diseases in the absence of underlying sinusitis. When patients meet the definition of chronic sinusitis as confirmed by CT scan, SOD of the sinuses can be indicated and/or effective in certain scenarios. Additional consensus statements regarding proper setting and safeguards for performing the procedure are described.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

The Benefits and Limitations of Targeted Training in Flexible Transnasal Laryngoscopy Diagnosis

Importance

Targeted laryngoscopy training can be used successfully in de novo learners.

Objective

To determine the value of targeted laryngoscopy education in interns.

Design, Setting, and Participants

This prospective study of fiberoptic laryngoscopy interpretations enrolled 13 participants in an academic hospital setting from August 1 to December 31, 2015. Participants included 10 postgraduate year 1 emergency and otolaryngology interns and 3 board-certified otolaryngology attending physicians.

Interventions

Participants viewed 25 selected and digitally recorded fiberoptic laryngoscopies and were asked to rate 13 items relating to abnormalities in the pharynx, hypopharynx, larynx, and subglottis; the level of concern; and confidence with the diagnosis. A laryngoscopy teaching video was then administered to the interns before rating a second set of 25 videos. Improvement in diagnosis and intraclass correlation coefficients (ICC) were calculated for each question and compared between the first and second administration.

Main Outcomes and Measures

Improvement in correct diagnosis of abnormalities in recorded laryngoscopies.

Results

All 13 participants completed the interventions. The ICCs for all questions were generally low for the intern groups and higher for the attending group. For vocal cord mobility, a preintervention ICC of 0.25 (95% CI, 0.16-0.37) improved to 0.47 (95% CI, 0.36-0.59) among interns after the intervention. The ICCs for vocal cord mobility were higher among attendings for the preintervention (0.89; 95% CI, 0.84-0.93) and postintervention (0.89; 95% CI, 0.83-0.93) assessments. Minimal improvement was observed in intern scores for base of tongue abnormalities, subglottic stenosis, vocal cord abnormalities, level of comfort, level of concern, pharyngeal abnormalities, or laryngeal, pharyngeal, and hypopharyngeal masses.

Conclusions and Relevance

Learning of flexible laryngoscopy can be improved with the use of a teaching video; however, additional interventions are needed to attain competence in accurately diagnosing upper airway lesions. Clinicians who seek to perform flexible laryngoscopy require robust training.

The association of allergic sensitization with radiographic sinus opacification

BACKGROUND

The relationship between allergic sensitization and radiographic sinus inflammation remains unclear.

OBJECTIVES

To determine whether specific allergen sensitization is correlated with sinonasal radiographic opacification.

METHODS

Patients with chronic sinonasal symptoms were selected and included if they had allergy testing and a computed tomography (CT) of the paranasal sinuses. Data regarding demographic characteristics, in vitro allergy test results, and comorbidities were collected. CTs were reviewed, and an overall Lund-Mackay score (LMS) was calculated for each patient. A two-sample t-test was used to compare mean LMS between patients who were sensitized and patients who were not sensitized. A multiple linear regression model was used to determine whether a relationship existed among LMS and allergy results, asthma, nasal polyps, immunoglobulin E (IgE) level, medication usage, in-season versus out-of-season CTs, age, and sex. Significance was determined at an alpha level of 0.05.

RESULTS

There were 437 patients included, of whom, 251 had positive specific allergen test results and 186 had negative test results. A total of 282 patients had allergic rhinitis symptoms without a documented diagnosis of sinusitis, and 155 carried a diagnosis of chronic rhinosinusitis. The mean LMS did not differ between patients who were sensitized and patients who were not sensitized (5.56 versus 5.28; p = 0.61). Linear regression demonstrated an increase in LMS in patients with asthma (p = 0.02), male sex (p < 0.01), elevated IgE (p < 0.01), a history of anaphylaxis (p = 0.03), and nasal polyps (p < 0.01). There was a statistically significant decrease in LMS in patients with an in-season CT (p = 0.02).

CONCLUSIONS

Patients with a positive specific in vitro allergen test result did not have higher overall rates of radiographic sinus inflammation. Asthma, male sex, polyps, elevated IgE, and a history of anaphylaxis were associated with higher LMS.

The Interactive Candidate Assessment Tool: A New Way to Interview Residents

The purpose of the residency interview is to determine the extent to which a well-qualified applicant is a good fit with a residency program. However, questions asked during residency interviews tend to be standard and repetitive, and they may not elicit information that best differentiates one applicant from another. The iCAT (interactive Candidate Assessment Tool) is a novel interview instrument that allows both interviewers and interviewees to learn about each other in a meaningful way. The iCAT uses a tablet computer to enable the candidate to select questions from an array of video and nonvideo vignettes. Vignettes include recorded videos regarding some aspect of the program, while other icons include questions within recognizable categories. Postinterview surveys demonstrated advantages over traditional interview methods, with 93% agreeing that it was an innovative and effective tool for conducting residency program interviews. The iCAT for residency interviews is a technological advancement that facilitates in-depth candidate assessment.

Association of oral flora with orbital complications of acute sinusitis

BACKGROUND

Acute and chronic sinusitis in children and adults can spread to the orbit. Oral flora has been seen in orbital infections, but the extent of synergy between pathogens in such infections remains unknown.

METHODS

A retrospective case series of patients with complicated sinusitis that involved the orbit from acute sinusitis who were admitted to a tertiary care hospital from January 2000 to December 2014 and who had surgical cultures obtained. Patients were identified by the International Classification of Diseases, Ninth Revision code for periorbital cellulitis, subperiosteal abscess, or orbital abscess.

RESULTS

Sixteen patients underwent surgical drainage via external drainage or endoscopic sinus surgery of an orbital infection associated with sinusitis and had cultures obtained. Nine patients (56%) grew organisms that exist in oral flora, whereas seven patients (44%) grew common respiratory pathogens. The most common organisms recovered were viridans group streptococcus (VGS) (50%), Staphylococcus aureus (31%), Eikenella corrodens (25%), and Prevotella species (19%). Oral flora anaerobes were cultured alongside a VGS species in seven of eight patients (88%) as opposed to the respiratory pathogens, which were less frequently associated with concomitant VGS infection (29%) (p = 0.04).

CONCLUSION

There are two main sources for infectious orbital complications from acute sinusitis: respiratory pathogens and oral flora. The high prevalence of concurrent anaerobic oral flora and VGS infection supports a suspected synergy between VGS and other oral organisms.

Correlation between the number of allergen sensitizations and immunoglobulin E: monosensitization vs polysensitization

BACKGROUND

The purpose of this study was to determine if total serum immunoglobulin E (IgE) could predict monosensitization compared to polysensitization in patients with allergic rhinitis (AR).

METHODS

This was a retrospective study of a cohort of 1073 patients who underwent allergy testing. Differences in total IgE level between unsensitized, monosensitized, and polysensitized subjects were calculated. Pearson correlation coefficient was calculated to determine whether there was a relationship between total IgE level and the number of positive allergen sensitizations. In addition, allergen sensitization class was calculated for each allergen sensitization and totaled for each patient. Pearson correlation coefficient was calculated to determine the relationship between total IgE level and weighted allergen sensitization by class.

RESULTS

There were 159 patients who were monosensitized compared to 492 patients who were polysensitized. Of the monosensitized patients, almost 50% (74) were sensitized to one or both dust mites. Total IgE was higher in polysensitized patients compared to monosensitized compared to controls (p < 0.001). Pearson correlation coefficient between total IgE and number of positive allergen sensitizations was 0.465 (p ≤ 0.001). Pearson correlation coefficient between total IgE and allergen class-weighted sensitizations was 0.529 (p ≤ 0.001).

CONCLUSION

IgE level can be used to predict monosensitization vs polysensitization. There is a moderate correlation between total IgE sensitization and the number of positive allergen sensitizations, as well as allergen class-weighted sensitizations.

Sleep quality outcomes after medical and surgical management of chronic rhinosinusitis

BACKGROUND

Endoscopic sinus surgery (ESS) has been shown to improve sleep in patients with chronic rhinosinusitis (CRS). However, it is unknown how this improvement compares with non-CRS control subjects' sleep, and medically treated CRS patients.

METHODS

Patients meeting diagnostic criteria for CRS and controls from the same reference population were recruited from 4 academic centers. Patients chose either medical or surgical treatment. The Pittsburgh Sleep Quality Index (PSQI) was administered to patients before treatment and after 6 months, whereas controls received the PSQI at enrollment.

RESULTS

The study population consisted of 187 cases (64 medical and 123 surgical) and 101 controls. Baseline PSQI scores for CRS patients (9.27 ± 4.76) were worse than for controls (5.78 ± 3.25), even after controlling for potential confounding factors such as asthma and allergy (p < 0.001). There was no significant difference in baseline PSQI between patients choosing medical vs surgical treatment. The PSQI score in surgical patients improved from 8.36 ± 5.05 to 7.44 ± 5.09 (p = 0.020). The PSQI score in medical patients demonstrated a nonsignificant increase with treatment from 8.71 ± 4.48 to 9.06 ± 4.80 (p = 0.640). After controlling for allergy and asthma, 6-month PSQI scores in medical patients remained significantly higher than in controls (p = 0.001), whereas a significant difference could not be demonstrated between surgical patients and controls (p > 0.05). PSQI subdomain analysis mirrored the overall findings.

CONCLUSION

Patients with CRS report worse sleep compared with controls. Surgically treated CRS patients show significant improvement in PSQI scores, whereas those continuing with medical management fail to improve and remain worse than controls.

Utility of Allergy Testing in Patients with Chronic Laryngopharyngeal Symptoms

Objective

To determine the utility of allergy evaluation in patients with chronic refractory laryngeal symptoms.

Study Design

Case series with chart review.

Setting

Tertiary academic medical center.

Subjects

All patients who underwent in vitro allergy testing at a single institution from 2006 to 2010, for a total of 998 patients.

Methods

Charts of patients who underwent in vitro allergy testing were identified. The charts were reviewed for the primary indication for allergy testing, as categorized into rhinitis complaints, chronic sinusitis, otitis media, and refractory laryngeal symptoms (globus, cough, throat clearing, increased secretions, and hoarseness). Results of allergy tests and comorbid conditions were analyzed and compared among groups.

Results

The positive yield of allergy testing in patients with primary laryngeal indications was 51.8%, 63.3% for rhinitis, 60.9% for sinusitis, and 33.3% for otitis media. The odds ratio of having a positive test was not statistically different for patients with laryngeal symptoms, rhinitis, or sinusitis. Patients with chronic laryngeal symptoms and positive allergy testing were most often sensitized to dust mites (63%) and least often sensitized to molds (1.3%).

Conclusions

Allergy testing in patients with chronic laryngeal symptoms yields positive results in equivalent proportion to patients with other common presenting symptoms. Dust mites sensitization is the most common sensitization in patients with allergic laryngitis.

Nasal epithelial myoepithelial carcinoma: An unusual cause of epiphora, a case report and review of the literature

Introduction:

Epithelial myoepithelial carcinoma (EMC) of the nasal cavity is a rare tumor, and here we describe the first case of EMC of the nasal cavity presenting with epiphora. A case presentation and review of the literature is provided.

Methods:

A case report is described of a 63-year-old man who presented with unilateral epiphora and was found via a thorough history and physical examination to have a nasal tumor. The physical examination consisted of an ocular examination, including probing and irrigation, and a detailed nasal examination (anterior rhinoscopy, nasal endoscopy). The nasal examination was prompted by the patient's report of concurrent nasal symptoms during history taking. Immunohistochemistry subsequently identified the nasal tumor as EMC. A literature search was performed to gain insights into similar malignancies of the nasal cavity.

Results:

Eight cases of EMC of the nasal cavity were identified in the literature, none of the patients presented with epiphora. The case presented here resulted in resolution of the patient's symptoms and no evidence of disease after surgical excision.

Conclusion:

Epithelial myoepithelial is a rare salivary gland malignancy that can arise in the nasal cavity. Unilateral epiphora with concurrent nasal symptoms should prompt nasal cavity examination for the possibility of an obstructive tumor.

Dosing of sublingual immunotherapy for allergic rhinitis: evidence-based review with recommendations

BACKGROUND

Since the mid 1980s, the clinical use of sublingual immunotherapy (SLIT) has dramatically increased. However, 1 of the primary barriers to providing SLIT is lack of a published dosing recommendations. The purpose of this work is to provide a range of effective SLIT dosing based upon a rigorous review of the existing evidence base. An appendix with SLIT dosing recommendations is also included.

METHODS

A comprehensive search of the past 25 years of the medical literature using PubMed was performed for specific antigens. Inclusion criteria for articles included: randomized, placebo-controlled studies of SLIT, studies with clinical allergic rhinitis outcomes, and dosing units available to determine the micrograms per month of major allergen administered. The extracted data was used to compile a range of effective SLIT dosing for individual antigens.

RESULTS

Seventy-five articles met the inclusion criteria, providing a range of effective dosing for some allergens. There was commonly a wide range in doses for particular antigens between the individual studies. For some antigens, there was significant overlap in dosage amount between studies showing efficacy and lack of efficacy. Clinical trials meeting inclusion criteria are not available for many allergens.

CONCLUSION

This study provided a comprehensive review of the published sublingual dosing ranges for specific antigens. The review provided a range of effective sublingual doses for some allergens, whereas for other allergens there was insufficient published data to determine specific doses. Recommendations for SLIT dosing were produced based on the data revealed in the review and expert opinion.

Preclinical validation of anti-nuclear factor-kappa B therapy to inhibit human vestibular schwannoma growth

Vestibular schwannomas (VSs), the most common tumors of the cerebellopontine angle, arise from Schwann cells lining the vestibular nerve. Pharmacotherapies against VS are almost non-existent. Although the therapeutic inhibition of inflammatory modulators has been established for other neoplasms, it has not been explored in VS. A bioinformatic network analysis of all genes reported to be differentially expressed in human VS revealed a pro-inflammatory transcription factor nuclear factor-kappa B (NF-κB) as a central molecule in VS pathobiology. Assessed at the transcriptional and translational level, canonical NF-κB complex was aberrantly activated in human VS and derived VS cultures in comparison to control nerves and Schwann cells, respectively. Cultured primary VS cells and VS-derived human cell line HEI-193 were treated with specific NF-κB siRNAs, experimental NF-κB inhibitor BAY11-7082 (BAY11) and clinically relevant NF-κB inhibitor curcumin. Healthy human control Schwann cells from the great auricular nerve were also treated with BAY11 and curcumin to assess toxicity. All three treatments significantly reduced proliferation in primary VS cultures and HEI-193 cells, with siRNA, 5 μM BAY11 and 50 μM curcumin reducing average proliferation (±standard error of mean) to 62.33% ± 10.59%, 14.3 ± 9.7%, and 23.0 ± 20.9% of control primary VS cells, respectively. These treatments also induced substantial cell death. Curcumin, unlike BAY11, also affected primary Schwann cells. This work highlights NF-κB as a key modulator in VS cell proliferation and survival and demonstrates therapeutic efficacy of directly targeting NF-κB in VS.

Time to competency, reliability of flexible transnasal laryngoscopy by training level: a pilot study

OBJECTIVE

To determine the progression of flexible transnasal laryngoscopy reliability and competency in otolaryngology residency training.

STUDY DESIGN

Prospective case control study.

SETTING

Academic otolaryngology department.

SUBJECTS

Medical students, otolaryngology residents, and otolaryngology attending physicians.

METHODS

Fourteen otolaryngology residents from PGY-1 to PGY-5 and 3 attending otolaryngologists viewed 25 selected and digitally recorded flexible transnasal laryngoscopies. The evaluators were asked to rate 13 items relating to abnormalities in the oropharynx, hypopharynx, larynx, and subglottis. The level of concern and level of comfort with the diagnosis were assessed. Intraclass correlations were calculated for each topic and by level of training to determine reliability within each class and compare competency versus attending interpretations.

RESULTS

Intraclass correlation of residents compared to attending physicians demonstrated significant improvements by year for left and right vocal fold immobility, subglottic stenosis, laryngeal mass, left and right vocal cord abnormalities, and level of concern. Additionally, pooled vocal cord mobility and pooled results in categories with good attending reliability demonstrated stepwise improvement as well. For these categories, resident reliability was found to be statistically similar to attending physicians in all categories by PGY-3. There were no trends for base of tongue abnormalities, pharyngeal abnormalities, and pharyngeal and hypopharyngeal masses.

CONCLUSIONS

Resident competency for flexible transnasal laryngoscopy progresses during residency to reliability with attending otolaryngologists by the PGY-3 year over key facets of the examination.

Scary Cases 2014

Program Description:

The Scary Cases 2014 miniseminar uses a case-base, interactive approach to providing education in patient care and risk management. Exceptionally scary cases presented by well-known experts and community-based clinicians will focus on what could or has gone wrong in the management of otolaryngology patients. Each expert will present a specific case that was difficult to manage, had unexpected morbidity, or resulted in litigation. Attendees will participate using the Audience Response System for key decisions during the case. Difficult cases are often great sources of learning. This miniseminar will provide education on how to anticipate and avoid unwanted outcomes.

Educational Objectives:

(1) Describe potential pitfalls inherent to the practice of otolaryngology that may lead to adverse outcomes or put patients at excessive risk. (2) Recognize legal principles of medical malpractice and learn ways to minimize risk of malpractice in the everyday practice of otolaryngology.

Time to Competency: Reliability of Flexible Transnasal Laryngoscopy by Resident Training Level

Objectives:

Determine the progression of flexible transnasal laryngoscopy reliability and competency in otolaryngology residency training.

Methods:

Prospective study of flexible transnasal laryngoscopy interpretations. Seventeen otolaryngology residents from PGY-1 to PGY-5 and 3 attending otolaryngologists viewed 25 selected and digitally-recorded flexible transnasal laryngoscopies. The evaluators were asked to rate 13 items relating to abnormalities in the oropharynx, hypopharynx, larynx, and subglottis. The level of concern and level of comfort with the diagnosis were assessed. Intraclass correlations were calculated for each topic and by level of training to determine reliability within each class, and competency compared to attending interpretations.

Results:

Intraclass correlation of residents compared with attending physicians demonstrated significant improvements by year for left vocal fold immobility (ICC 0.85-0.96), right vocal cord immobility (ICC 0.80-0.97), subglottic stenosis (ICC 0.70-0.97), and level of concern (ICC 0.72-0.87). There were no trends for base of tongue abnormalities, pharyngeal abnormalities, pharyngeal masses, and hypopharyngeal masses. For vocal cord immobility, subglottic stenosis, and level of concern, resident reliability was found to be statistically similar to attending physicians in all categories by PGY-3.

Conclusions:

Resident competency for flexible transnasal laryngoscopy progresses during residency to reliability with attending otolaryngologists by PGY-3 over key facets of the examination. Flexible laryngoscopy may be a useful metric for procedural competency assessment during residency training.

Early detection of factual knowledge deficiency and remediation in otolaryngology residency education

OBJECTIVES/HYPOTHESIS

Within otolaryngology residency training, the annual Otolaryngology Training Examination (OTE) is the primary method used to assess, quantify, and compare the factual knowledge acquired by each resident. The objective of this study was to develop a more frequent method for tracking of factual knowledge to prevent educational delay.

STUDY DESIGN

Retrospective analysis of educational scores.

METHODS

For each didactic lecture within a single otolaryngology residency training program, multiple choice questions were provided before and after each lecture. Questions were based on lecture objectives that were derived from the American Board of Otolaryngology curriculum. Scores were tracked over the course of 1 academic year and compared to the scores of residents on the OTE administered in that year to determine correlation with a validated measure of factual knowledge. The effect of remedial measures on improvement in OTE scores was determined.

RESULTS

Over the course of 1 academic year, there were 328 questions presented to 12 residents before and after 32 lectures in the didactic program. Ten residents completed an average of 244 questions. Overall OTE scores demonstrated a significant and very strong correlation to lecture question scores (Pearson r = 0.86, P = .002). Remedial measures for residents during the previous 5 years who had inadequate OTE scores were successful in improving scores (P = .002).

CONCLUSIONS

A structured didactic program that uses review questions to assess knowledge can be used to track acquisition of factual knowledge. Early identification of residents with deficiencies facilitates the development of individualized learning plans that result in successful remediation.

Scary Cases 2013

Program Description:

The Scary Cases 2013 miniseminar uses a case-based, interactive approach to education in patient care and limiting risk. Cases presented by well-known experts and community-based clinicians will focus on what could go wrong or has gone wrong in the management of otolaryngology patients. Each expert will present a specific case that was difficult to manage, had unexpected morbidity, or resulted in litigation. Attendees will participate with an audience response system for key decisions during the case. Difficult cases are often great sources of learning. This miniseminar will provide education on how to anticipate and avoid unwanted outcomes.

Educational Objectives:

1) Identify pitfalls that may lead to adverse outcomes or put patients at risk. 2) Diagnose certain otolaryngologic conditions that can easily go undetected. 3) Evaluate the management of cases with high potential for malpractice litigation.

Factors affecting time to revision sinus surgery for nasal polyps: a 25-year experience

OBJECTIVES/HYPOTHESIS

Surgical treatment for chronic rhinosinusitis with nasal polyps (CRSwNP) is often followed by polyp regrowth with return of symptoms. The purpose of this study is to identify clinical factors that influence the time interval to revision sinus surgery in patients with nasal polyps.

STUDY DESIGN

Retrospective cohort study.

METHODS

Records of 299 individuals who underwent two or more surgeries for the diagnosis of nasal polyps by the senior author (RM) from 1987 through 2011 were reviewed. The time between surgical interventions were compared to patient demographics, comorbidities, endoscopic examination, computed tomography (CT) stage, extent of surgery, and pathologic findings.

RESULTS

The mean time interval between polyp surgeries was 4.87 ± 3.61 years (range 0.7-18.6 years). The median time to revision surgery was shorter in patients who smoked compared to nonsmokers (2.82 vs. 4.31 years, respectively, P = .022) and longer in patients who underwent middle turbinate resection rather than preservation (4.56 vs. 3.93 years, respectively, P = .048). Kaplan-Meier survival analysis confirmed these findings, but the beneficial effect of turbinectomy appeared to dissipate by 8 years. Neither a history of asthma nor advanced CT stage influenced the time to revision surgery.

CONCLUSION

The time course between sinus surgeries in patients with regrowth of nasal polyps appears to be affected by certain modifiable extrinsic factors, including smoking on the part of the patient and operative technique on the part of the surgeon. The performance of middle turbinate resection during sinus surgery appears to extend the time interval until a revision procedure is required.

Embryonic disruption of the candidate dyslexia susceptibility gene homolog Kiaa0319-like results in neuronal migration disorders

Developmental dyslexia, the most common childhood learning disorder, is highly heritable, and recent studies have identified KIAA0319-Like (KIAA0319L) as a candidate dyslexia susceptibility gene at the 1p36-34 (DYX8) locus. In this experiment, we investigated the anatomical effects of knocking down this gene during rat corticogenesis. Cortical progenitor cells were transfected using in utero electroporation on embryonic day (E) 15.5 with plasmids encoding either: (1) Kiaa0319l small hairpin RNA (shRNA), (2) an expression construct for human KIAA0319L, (3) Kiaa0319l shRNA+KIAA0319L expression construct (rescue), or (4) controls (scrambled Kiaa0319l shRNA or empty expression vector). Mothers were injected with 5-bromo-2-deoxyuridine (BrdU) at either E13.5, E15.5, or E17.5. Disruption of Kiaa0319l function (by knockdown, overexpression, or rescue) resulted in the formation of large nodular periventricular heterotopia in approximately 25% of the rats, which can be seen as early as postnatal day 1. Only a small subset of heterotopic neurons had been transfected, indicating non-cell autonomous effects of the transfection. Most heterotopic neurons were generated in mid- to late-gestation, and laminar markers suggest that they were destined for upper cortical laminae. Finally, we found that transfected neurons in the cerebral cortex were located in their expected laminae. These results indicate that KIAA0319L is the fourth of four candidate dyslexia susceptibility genes that is involved in neuronal migration, which supports the association of abnormal neuronal migration with developmental dyslexia.

Mining Immune Epitopes in Ménière’s Disease and Sudden Sensorineural Hearing Loss

Objective: Etiologies for Ménière’s disease and sudden sensorineural hearing loss remain unknown. Indirect evidence exists for allergy-mediated or autoimmune process. The purpose of this study is to determine whether immunogenic proteins share similar sequences with inner ear proteins, which may lead to cross-reactivity and immune activation in inner ear disorders.

Method: Comprehensive bioinformatic primary sequence analyses of intact and mutated proteins associated with human syndromic and nonsyndromic hearing loss and proteins expressed in the human inner ear was performed. Comparison of sequences to epitopes in the Immune Epitope Database was performed by exact match, BLAST, and BLOSUM62 score computational algorithms.

Results: Computational analysis of primary protein sequence for 81 known inner ear proteins, 102 proteins from genes identified in syndromic and non-syndromic hearing loss, and 438 protein sequences with known mutations that contribute to sensorineural hearing loss was compared to 151,086 epitopes previously implicated in allergic, autoimmune, and infectious disorders within the Immune Epitope Database. The exact match and BLAST algorithms identified 1925 and 97 unique epitope matches, respectively. Top BLOSUM62 score algorithm resulted in a single hit for the 47 kDa membrane antigen. Other epitopes included those seen in allergic rhinitis, infectious diseases, and autoimmune disorders.

Conclusion: Abnormal immune activation is suspected in Ménière’s disease and SSNHL. Candidate immune epitopes were identified that may contribute to pathogenesis of these disorders. While these epitopes await clinical validation, they present novel targets for diagnosis and treatment of sensorineural hearing loss.

Pathways analysis of molecular markers in chronic sinusitis with polyps

OBJECTIVE

To perform a comprehensive molecular pathways analysis of genes identified through genome-wide expression profiling and the published literature for chronic sinusitis with polyps.

STUDY DESIGN

Molecular pathways analysis.

SETTING

Academic medical center.

METHODS

A molecular pathways analysis of gene biomarkers discovered through hypothesis-driven and high-throughput molecular studies was performed. Genes identified with a PubMed literature search were analyzed with Ingenuity Pathways Analysis software to identify central molecules implicated in the pathogenesis of chronic sinusitis with polyps. The central pathways were then compared with those identified through genome-wide expression profiling of ethmoid polyps.

RESULTS

A total of 97 molecules were investigated with Ingenuity Pathways Analysis based on 55 studies that evaluated differences in gene expression (39), genetic variation (12), or proteomics (4). The analysis revealed 9 statistically significant molecular networks containing central nodes that included transcription factors, protein kinases, cytokines, and growth factors/receptors. The highest scoring networks implicated nuclear factor kappa-B, tumor necrosis factor, and mitogen-activated protein kinases. The majority of pathways in the literature review analysis overlapped with those identified through a single genome-wide expression study.

CONCLUSIONS

Chronic sinusitis with polyps is a complex disease with suspected contribution of multiple genetic and environmental factors. The search for causative genes has led to the discovery of numerous candidates. Pathways analysis applied to these candidate genes identified common central molecules that are likely to be key mediators of the disease process. Novel therapies targeting these molecules may be applicable for the treatment of chronic sinusitis with polyps.

Topographic gene expression in the sinonasal cavity of patients with chronic sinusitis with polyps

OBJECTIVE

To determine whether variations in gene expression exist at multiple subsites along the sinonasal tract in patients with chronic sinusitis with polyps and in healthy controls.

STUDY DESIGN

Prospective, controlled study.

SETTING

Academic medical center.

SUBJECTS AND METHODS

Tissue expression levels of 5 genes, previously found to be characteristic of ethmoid polyps, were measured using real-time quantitative polymerase chain reaction in 100 sinonasal tissue samples. Specimens harvested from 5 regions--the ethmoid sinus, septum, inferior turbinate, middle turbinate, and lateral nasal wall--in 10 patients with chronic sinusitis and ethmoid polyps were compared to tissue from similar regions in 10 control patients without sinusitis. Western blot analysis was performed to validate differential gene expression at the protein level.

RESULTS

Gene expression levels of ethmoid polyps differed significantly from those of healthy ethmoid mucosa, as well as tissue from 4 surrounding anatomical sites in both patients with chronic sinusitis and controls. Alterations specific to the polyp tissue included downregulated genes, prolactin-induced protein (fold change 377.2 ± 169.0, P < .0001), and zinc α2-glycoprotein (fold change 72.1 ± 26.5, P < .0001), as well as upregulated genes, met proto-oncogene (fold change 2.5 ± 0.7, P = .029), and periostin (fold change 7.5 ± 3.4, P = .003). No significant differences in gene expression was found for neurabin 2 (fold change 1.0, P = .99).

CONCLUSION

The transcriptional pattern of ethmoid polyps appears to be unique compared with other subsites in the sinonasal cavity of patients with chronic sinusitis. Care must be taken when collecting specimens for molecular studies of the sinonasal tract to differentiate polyp from nonpolyp tissue in chronic sinusitis.

Claim validity of print advertisements found in otolaryngology journals

OBJECTIVE

To evaluate the accuracy and scientific evidence supporting product claims made in print advertisements within otolaryngology journals.

DESIGN

Cross-sectional survey with literature review and multiple-reviewer evaluation. Fifty claims made within 23 unique advertisements found in prominent otolaryngology journals were selected. References to support the claims were provided within the advertisements or obtained through direct request to the manufacturer. Five academic otolaryngologists with distinct training and geographic practice locations reviewed the claims and supporting evidence. Each physician had substantial experience as an editorial reviewer, and several had specific training in research methodology and scientific methods.

RESULTS

Of the 50 claims, only 14 were determined to be based on strong evidence (28%). With regard to the supporting references, 32 references were published sources (76%), while 3 references were package inserts and/or prescribing information (7%). Interobserver agreement among the reviewers overall was poor; however, when 3 or more of the reviewers were in agreement, only 10% of the claims were deemed correct (n = 5). Reviewers also noted that only 6% of the claims were considered well supported (n = 3).

CONCLUSION

Advertisers make claims that appear in respectable journals, but greater than half of the claims reviewed were not supported by the provided reference materials.

Revision endoscopic orbital decompression in the management of Graves' orbitopathy

OBJECTIVE

Endoscopic orbital decompression has proved to be an effective treatment for Graves' orbitopathy. In select patients, however, persistent or recurrent orbital symptoms necessitate additional therapy. The objective of this study is to determine the safety and effectiveness of revision endoscopic orbital decompression in patients with refractory Graves' orbitopathy.

STUDY DESIGN

Case-control series.

SETTING

Academic medical center.

METHODS

The study population consisted of 10 patients with Graves' orbitopathy who underwent 13 revision endoscopic orbital decompressions (three bilateral cases) between 1991 and 2008. Outcome measures, including reduction in proptosis, improvement in visual acuity, and complication rates, were compared with a control cohort of 10 consecutive patients (16 orbits) who underwent primary endoscopic decompression during the same time period.

RESULTS

Indications for revision decompression included exposure keratopathy (n=8, 62%), optic neuropathy (n=3, 23%), and gaze restriction (n=2, 15%). There were no intraoperative complications. Mean reduction in proptosis was 1.4 mm less for patients who underwent revision decompression compared with primary cases (mean decompression 3.6+/-1.0 mm vs 5.0+/-2.1 mm, respectively), although this difference was not statistically significant (P=0.13). Visual acuity improved in 62 percent of revision cases, compared with 20 percent of primary cases (P=0.09). Rates for postoperative complications, which included sinusitis and frontal mucocele formation, were also similar between revision and primary decompression groups (38% vs 13% respectively, P=0.17).

CONCLUSIONS

This report is the first to describe the endoscopic technique for revision orbital decompression. It appears to be a safe and effective procedure for the treatment of refractory orbitopathy in patients with Graves' disease.

S123 – New Approaches to Infratemporal Fossa Foreign Body Removal

Objectives

1) To understand indications for removal of foreign bodies (FB) from the head and neck. 2) To be able to describe the use of new surgical technologies for FB removal from the head and neck region. 3) To understand the clinical applications of a novel, minimally-invasive technique for removal of FB from the infratemporal fossa.

Methods

A retrospective review of 2 cases of infratemporal fossa foreign bodies, which were referred to a tertiary care facility for management utilizing a novel transoral, endoscopic, image-guided approach.

Results

Both patients presented with pain and trismus following failed attempts to retrieve foreign bodies–1 broken hypodermic needle and 1 torn cottonoid sponge-through open explorations. Use of endoscopic equipment for visualization and image-guidance system for precise localization enabled both objects to be removed through a transoral approach. Surgical removal resulted in improvement in pain and trismus in both patients who were discharged within 24 hours.

Conclusions

A new approach is now available for the minimally-invasive retrieval of radio-opaque foreign bodies in the infratemporal fossa, which avoids the need for extensive surgical dissection or an external incision.

Management of unexpected cerebrospinal fluid fistulae during endoscopic sinus surgery

BACKGROUND

The aim of this study was to determine the incidence and perioperative management of patients with cerebrospinal fluid (CSF) fistulas during endoscopic sinus surgery (ESS) in New York State.

METHODS

A questionnaire was mailed to otolaryngologists in New York State who were registered with the American Academy of Otolaryngology, Head and Neck Surgery in November 2005. Questions addressed the incidence and perioperative care of patients with successful closure of unexpected CSF fistula during ESS.

RESULTS

Twenty-five percent of respondents have experienced at least one episode of unexpected CSF fistula during ESS over the prior 5 years, with a calculated incidence of 0.16%. Surgeons most often (46%) observed patients for 1-2 days. Antibiotics were used in 93% of patients. A lumbar drain was most commonly not used. Repair techniques most often used an intranasal flap or graft (92%).

CONCLUSION

The incidence of unexpected CSF fistula during ESS may be lower than previously reported. A majority of surgeons use an intranasal flap or graft in repair with antibiotic use, with no consensus regarding use of lumbar drain or inpatient observation. More study is needed to determine consensus algorithms for management of CSF leaks during ESS.

A new in vivo microvascular preparation of the hamster ovary

Ovarian function in the cycling female is intimately related to and dependent upon significant microvascular regulation and restructuring. To enable investigation of the microvascular determinants of ovarian function, we present an in vivo preparation of the golden hamster ovary. The preparation does not compromise the ovarian vascular supply. The viability and responsiveness of the preparation were confirmed by quantifying arteriolar responses to vasoactive agents in 17 hamsters. Small surface arterioles (mean diameter 15-16 microns) responded with statistically significant changes in diameter to adenosine and oxygen and showed significant, dose-dependent constriction in response to norepinephrine and the NO synthase inhibitor L-NAME. Other key findings included extremely high microvascular permeability that varied with the day of the estrous cycle and functionally significant architectural features of the utero-ovarian vascular network. Potential applications of the preparation include elucidation of the role of the microvasculature in follicular development and luteal regression, investigation of utero-ovarian crossregulation, and development of a model for the study of ovarian angiogenesis and vascular regression.

Adverse neonatal effects of maternal labetalol treatment

Two infants with features of severe beta adrenergic blockade, pericardial effusions, and myocardial hypertrophy were born to mothers receiving long term treatment with oral labetalol for hypertension in pregnancy. Labetalol was implicated in the aetiology of these problems. Pericardial effusion and myocardial hypertrophy have not been associated with labetalol toxicity in neonates.

Association between blood lactate and acid-base status and mortality in ventilated babies

AIM

To investigate the relation between common acid-base parameters and blood lactate concentrations and their prognostic importance in sick, ventilated neonates.

METHODS

Two hundred and seventy eight serial simultaneous measurements of arterial acid-base status and blood lactate concentrations were carried out in 75 mechanically ventilated neonates with indwelling arterial catheters (gestational age and birthweight, median (range) -29 (23-40) weeks, and 1340 (550-4080) g, respectively).

RESULTS

There were no correlations between arterial blood lactate and pH and base excess within subjects (r = 0.07 and r = -0.06, respectively) and only weakly positive but clinically irrelevant positive correlations between subjects (r = 0.28 and r = 0.27) in this group. Even in those infants who had not received any bicarbonate before their initial measurements (n = 48), there were no correlations between initial blood lactate concentrations and pH (r = 0.27), base excess (r = 0.17), or serum bicarbonate concentrations (r = -0.18). There was no relation between peak lactate concentration (PLC) and base excess (r = 0.16), and only a weak correlation between peak lactate concentration (PLC) and pH (r = 0.28). Negative base excess was an insensitive indicator of raised lactate concentrations. Only two out of 33 (6%) instances of hyperlactataemia (lactate > 2.5 mmol/l) would have been identified with a base excess < -10 mmol/l as a cutoff. Lower cutoff values of base excess or pH performed no better. Raised lactate concentrations were associated with increased mortality at all levels. While six of 53 (11%) infants with a PLC < 2.5 mmol/l died, this proportion increased to four of 15 (27%) with a PLC between 2.5-5.0 mmol/l, and four of seven (57%) with a PLC > 5.0 mmol/l. Infants showing little rise or a substantial fall in blood lactate fared better than those with persistently raised values. A clinically important increase in blood lactate preceded the development of clinical markers of deterioration and complications in six infants.

CONCLUSIONS

Contrary to popular belief, pH or base excess cannot be used as proxy measures for blood lactate concentration, and independent measurement of the latter are needed. Blood lactate concentrations may provide an early warning signal and important prognostic information in ill, ventilated neonates. In this regard, serial measurements of blood lactate are more useful than a single value.

Measuring blood glucose in neonatal units: how does hemocue compare?

Rapid and reliable determination of blood glucose concentration is essential during the neonatal period to prevent adverse neurodevelopmental outcome from hypoglycaemia. Despite their unreliability, reagent strip methods continue to be used extensively in neonatal nurseries due to their rapidity and convenience. Recently, a new portable laboratory standard technique has been introduced (HemoCue B-Glucose system) for whole blood glucose determination. It is particularly suitable for near-patient testing in neonatal units. This new method, as well as other established methods of whole blood (Yellow Springs Instrument (YSI) and a hexokinase method on Cobas Bio), and plasma (Kodak Ektachem) glucose measurement, were therefore evaluated for their accuracy and concordance of measurements taken in the neonatal period. There were substantial discrepancies among the four methods of glucose measurement with wide limits of agreement between these methods. The glucose concentrations measured by HemoCue and YSI (n = 206), HemoCue and hexokinase (n = 113), HemoCue and plasma glucose on Ektachem (n = 69) and hexokinase and Ektachem (n = 66) were likely to differ by -29 to +61%, -23 to +56%, -36 to +65%, and -19 to +30%, respectively. Even the laboratory methods of blood glucose determination, therefore, can not be used interchangeably. Using a model based approach, the probabilities of "discordant" classification as hypo- or normo-glycaemia were estimated to be 6.8%, 6.5%, and 7.1% between HemoCue and YSI, HemoCue and hexokinase on Cobas Bio, and HemoCue and Ektachem analysers, respectively. In view of these low probabilities of discordant classification with other glucose analysers, the HemoCue system may offer a reasonable compromise between bedside and laboratory blood glucose estimations in neonates.