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Biomedical subjects

Karen H Calhoun

Publications and source records attributed to Karen H Calhoun.

14 recordsLinked to original sources

Effect on hospital-wide sedation practices after implementation of the 2001 JCAHO procedural sedation and analgesia guidelines.

OBJECTIVE: To describe the effect of implementing the Joint Commission on Accreditation of Healthcare Organization's guidelines for procedural sedation and analgesia (PSA) on the frequency of adverse events occurring during sedation. DESIGN: Prospective, descriptive study. SETTING: Urban, tertiary care children's hospital. PARTICIPANTS: Patients requiring PSA. INTERVENTIONS: A PSA committee and a standardized protocol for PSA were developed during a 6-month period. Institutional oversight was initiated to monitor practitioner compliance with the program. Data were abstracted from the sedation record. MAIN OUTCOME MEASURES: The change in incidence of adverse events during PSA during the study. The strength of the association was determined by computing the Pearson product moment correlation. RESULTS: A total of 14 386 patients received PSA between July 1, 2001, and June 30, 2004. During the study, 7.6% of patients had an adverse event, with the most common being hypoxemia (39.7% of all adverse events). A trend toward a decrease in the incidence of adverse events was found during the study (Pearson product moment correlation, -0.68; P<.001). CONCLUSIONS: Implementation of the 2001 Joint Commission on Accreditation of Healthcare Organizations guidelines for the provision of PSA appeared to lead to a decrease in the incidence of adverse events during the study. Implementation of uniform standards of monitoring and care for the provision of PSA may lead to safer conditions for pediatric patients undergoing PSA.

Adolescent↗

Relationship between rhinosinusitis symptoms and mucociliary clearance time.

OBJECTIVE: To determine the correlation between rhinosinusitis symptoms as assessed by the Sino-Nasal Outcomes Test-20 (SNOT-20) and mucociliary clearance as assessed by the saccharin method. STUDY DESIGN AND SETTING: This was a cross-sectional study of 50 adult volunteers. Subjects completed the SNOT-20, and mucociliary clearance was determined with the saccharine method. Correlation coefficients (Spearman's Rho) were calculated for the global SNOT-20 score. RESULTS: The SNOT-20 scores varied from 20 to 54 (mean 30.28) with a possible range of 20 to 100. Clearance times varied from 418 to 2865 seconds (mean 999). There was no significant correlation between global SNOT-20 score and clearance time (r = 0.196). CONCLUSIONS: There is no significant correlation between rhinosinusitis symptoms as assessed by SNOT-20 scores and mucociliary clearance. SIGNIFICANCE: Mucociliary clearance is important for the health of the sinonasal cavities, but clearance time does not appear to be associated with symptom severity in the population studied. EBM RATING: A-1b.

Adult↗

The effects of intradermal and topical mitomycin C on wound healing.

OBJECTIVE: To determine the effect of intradermal and topical mitomycin C (MMC) on skin wound healing. STUDY DESIGN/SETTING: A prospective, controlled study in a rat wound model performed in an academic medical center. RESULTS: Intradermal and topical MMC application decreased wound integrity when compared with saline-treated animals at 1 week, 2 weeks, 1 month, and 6 months. Skin necrosis occurred in animals that received intradermal MMC. Hemotoxylin and eosin and immunohistochemical staining showed no consistent difference between treatment arms. Fibrosis and collagen deposition were reduced in MMC-treated wounds on trichrome staining. CONCLUSIONS: MMC-treated wounds showed decreased wound strength compared with controls. Intradermal MMC can cause skin necrosis. Histologic findings did not always correspond with clinical data. SIGNIFICANCE: The data suggest cautious use of MMC in clinical situations when wound breaking strength is critical.

Animals↗

Reconstruction of the auricle.

The intricate and delicate anatomy of the external ear (auricle) makes reconstruction a daunting task for beginning as well as experienced surgeons. The complex framework of the auricle is composed of graceful curves, peaks, and valleys of a thin pliable uniform thickness of cartilage. This article discusses techniques for reconstruction of the auricle.

Cartilage↗

The association of tongue scalloping with obstructive sleep apnea and related sleep pathology.

OBJECTIVE: The association between OSAS and patient history and physical exam findings is previously established; however, to our knowledge there are no studies that evaluate the role of tongue scalloping as a reliable clinical indicator for OSA, snoring, or the presence of other sleep pathology as evidenced by polysomnography. This study evaluates the hypothesis that such an association exists. SUBJECTS AND METHODS: Sixty-one otolaryngology clinic patients were evaluated by history and physical exam for the presence and degree of tongue scalloping, snoring, and other previously established clinical indicators for sleep-disordered breathing and obstructive apnea. Twenty-five of the 61 study patients were additionally evaluated by overnight polysomnography to provide conclusive diagnosis of sleep pathology. The degree of tongue scalloping was graded from 0 to 3 and its significance as a screening, diagnostic, and predictive factor for sleep pathology was then statistically determined. RESULTS: Twenty-seven patients (44%) had known or newly documented OSA and 47 (77%) had a history of snoring. Twenty-seven patients (44%) had some degree of tongue scalloping (1-3) and 74% of these patients were male. The presence of any degree of tongue scalloping (grade 1-3) in patients with known or newly documented OSA showed sensitivity, specificity, PPV, and NPV of 52%, 68%, 70%, and 50% respectively. The presence of tongue scalloping in patients with either known snoring history or newly documented snoring showed sensitivity, specificity, PPV, and NPV of 47%, 64%, 81%, and 26% respectively. Presence of tongue scalloping was 71% specific for abnormal sleep efficiency (<85%), 70% specific for abnormal AHI (>5), and 86% specific for nocturnal desaturation >4% below baseline. Presence of tongue scalloping also showed PPV of 67% for abnormal AHI, 89% for apnea or hypopnea, and 89% for nocturnal desaturation. Presence and severity of tongue scalloping showed positive correlation with increasing Mallampati and modified Mallampati airway classification. CONCLUSIONS: In high-risk patients we found tongue scalloping to be predictive of sleep pathology. Tongue scalloping was also associated with pathologic polysomnography data and abnormal Mallampati grades. We feel the finding of tongue scalloping is a useful clinical indicator of sleep pathology and that its presence should prompt the physician to inquire about snoring history.

Adult↗

Alterations of nasal mucociliary clearance in association with HIV infection and the effect of guaifenesin therapy.

OBJECTIVES: To determine if human immunodeficiency virus (HIV) infection is associated with a prolonged mucociliary clearance time (MCT) and to evaluate the effect of guaifenesin on MCT in HIV+ patients. STUDY DESIGN: A cross-sectional study comparing HIV+ and HIV- volunteers followed by a prospective, randomized, double-blind, placebo-controlled study of HIV+ patients before and after guaifenesin treatment. METHODS: Twenty-five HIV+ patients and 29 HIV- controls were enrolled and MCT was measured using the saccharin method. A separate group of 20 HIV+ patients participated in the second arm of the study and underwent saccharin testing before and after a 3-week course of guaifenesin or placebo. All study participants completed a medical history questionnaire, a sinonasal symptom (SNOT-16) survey, and were examined with both anterior rhinoscopy and rigid nasal endoscopy. RESULTS: There was a significant difference (P < .002) in the MCT between the HIV+ group (13.3 +/- SD 7.5 minutes) and the HIV- controls (9.2 +/- SD 3.9 minutes). The difference in MCT between the guaifenesin and placebo groups did not reach statistical significance (P >.05). The HIV+ group had a higher SNOT-16 score compared to HIV- controls (21.1 vs. 7.4, P < .001). Guaifenesin therapy in HIV+ patients led to a significant improvement in the SNOT-16 score (P < .05). CONCLUSIONS: Compared to HIV- controls, HIV+ patients have a prolonged MCT and more sinonasal symptoms as indicated by a higher SNOT-16 score. Guaifenesin therapy was associated with improved SNOT-16 scores, although there was not a detectable improvement in MCT. Use of guaifenesin in HIV+ patients with sinonasal disease may lead to improved patient perception of quality of life.

Adult↗

Patterns of mold sensitivity in the subtropical Gulf Coast.

OBJECTIVES: We sought to determine the patterns of mold- and nonmold positive skin tests in a subtropical Gulf Coast climate and to determine whether any particular positive skin tests predict "allergic versus nonallergic" status as shown on the full panel of skin testing. STUDY DESIGN AND SETTING: We conducted a retrospective evaluation of serial endpoint allergy skin test results in 75 consecutive patients from a tertiary referral medical center. RESULTS: Of the 67 evaluable patients, 58 (86.6%) had a positive skin test to at least 1 antigen. The most common positive skin tests were in response to cockroach, Dermatophygoides farinae, Bermuda grass, false ragweed, mesquite, Stemphylium, Curvularia, short ragweed, and Timothy grass. There were no identifiable groups of antigens that tended to occur together. Screening with a panel of 6 antigens (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have correctly predicted whether the patient would react to any or none of the full panel of antigens. CONCLUSION: Cockroach, dust mite, and a grass were the most common positive skin tests among our patients, with many patients also having positive skin tests to molds. Although there is evidence that cross-reactivity exists among different mold species, we were unable to identify any clusters of mold reacting together in individual patients. In our patient population, a 6-allergen screening panel (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have accurately distinguished "allergic" from "nonallergic" patients, as demonstrated on the full panel of skin testing. SIGNIFICANCE: A small (6-antigen) screening panel accurately predicted "allergic" versus "nonallergic" as shown by our full panel of skin testing. This is useful clinically when an "allergic versus nonallergic" etiology of sinonasal symptoms affects treatment choices.

Adult↗

Smoking in chronic rhinosinusitis: a predictor of poor long-term outcome after endoscopic sinus surgery.

OBJECTIVE: This study was designed to determine whether smoking patients have poorer outcomes after endoscopic sinus surgery (ESS) based on a reliable validated rhinosinusitis-specific quality-of-life outcomes test. STUDY DESIGN: Retrospective chart and computed tomography (CT) review with telephone and letter questionnaire. METHODS: Charts of 230 adult patients undergoing ESS for chronic rhinosinusitis between January 1995 and December 1998 were reviewed. Each participating patient completed a detailed questionnaire, including the Sino-Nasal Outcome Test-16 (SNOT-16), at an average of 52 months after surgery. Preoperative CT scans were reviewed and the findings used to stage the patients' conditions. Multivariate analysis was used to assess these data. RESULTS: Eighty-two patients completed the questionnaire, with 26 who smoked at the time of surgery and continued to smoke at the time of answering the questionnaire (Smokers). Average SNOT-16 score in Smokers was 27.5, versus 18.2 in those who did not smoke at the time of surgery (Non-Smokers). There was a statistically significant correlation between elevated SNOT-16 scores and smoking (P <.001) and antibiotic use within the past year (P <.001). There was an association between high SNOT-16 scores and both prior smoking and passive smoke exposure that did not reach statistical significance (P =.055 and P =.267, respectively). CT staging scores and prior ESS were not statistically correlated with SNOT-16 scores. CONCLUSIONS: Smoking is associated with statistically worse outcomes after ESS based on average SNOT-16 scores. Although no investigator has proved that the effects of smoking on sinonasal health are reversible, we counsel smoking patients considering ESS about the desirability of smoking cessation (for this and many health reasons), and the possibility of a poorer postsurgery outcome should they continue smoking.

Chronic Disease↗

Treatment and outcome of human bites in the head and neck.

OBJECTIVE: Our goal was to review head and neck human bite injuries for demographic, treatment, and outcome data to identify factors influencing infection. Study design Retrospective chart review of all human bite injuries (adult and pediatric) over 10 years. SETTING: Tertiary referral medical center. RESULTS: We reviewed 40 human bites (average follow-up, 139 days). Young males were the most common victims, altercation was the most common etiology, and auricular avulsion was the most common injury. Six wounds closed primarily became infected (40%) versus no wound infection with delayed closure. Primary wound closure (P <.01), exposed cartilage (P <.07), and less than 48 hours of intravenous antibiotics (P <.06) were associated with postoperative infection (P <.01). CONCLUSION: Human bites to the head and neck, especially those with exposed cartilage, are best treated with at least 48 hours of intravenous antibiotics and delayed surgical closure (>24 hours postinjury) to prevent infection. SIGNIFICANCE: This information enables the clinician who sees these bite wounds infrequently to understand the treatment associated with avoiding infection.

Adult↗

Bone that best matches the properties of the mandible.

OBJECTIVE: The main advantage of primary oromandibular reconstruction using free vascularized bone-containing flaps is improved oral function from (1) the maintenance of mandibular and soft tissue architecture and (2) dental rehabilitation through osseointegrated implants. Bone dimensions, volume, quality, and the ability of the bone to withstand masticatory forces are important factors in achieving successful osseointegration. Previous studies have objectively examined the dimensions of bones used in oromandibular reconstruction, but few have addressed their biomechanical properties. The purpose of this study was to compare the dimensional and biomechanical properties of the bones commonly used in oromandibular reconstruction with those of the mandible. METHODS: Eleven formalin-fixed cadavers were used. The mandibles, fibulae, iliac crests, scapulae, clavicles, second metatarsals, radii, and anterior ribs were harvested. Measurements of the dimensions of the bones were made with calipers at multiple sites. Three-point break strength and screw pulling force tests were then performed on all of the bones. RESULTS: The fibulae, iliac crests, and clavicles had dimensions that best matched those of the mandible. The three-point break strength and screw pulling force tests were consistently the highest for the mandibles and fibulae, followed by the clavicles, scapulae, iliac crests, metatarsals, radii, and ribs, in that order. CONCLUSIONS: The fibula is the bone that best matches the properties of the mandible.

Aged↗

Digital image archiving.

The digital camera has become a valuable component of the clinical practice for many otolaryngologist head and neck surgeons. Because several technical details distinguish digital cameras from their standard 35-mm counterparts, having some knowledge of these features is crucial for integrating digital imaging successfully into a practice. This chapter discusses these cameras and digital output, with an emphasis on their use in a medical practice. The author also explores current and future applications and gives a summary of limitations and benefits.

Computer Storage Devices↗

The effect of tension on patency of rat femoral artery anastomoses.

OBJECTIVE: To determine experimentally the role of tension in the failure of microarterial anastomoses. METHODS: Sixteen microarterial anastomoses were performed in femoral arteries from adult Sprague-Dawley male rats after resecting 0, 1, 2, or 3 mm. The percentage of vessel excised was calculated. The vessel was then examined in approximately 1 week for patency. Next, 5 femoral arteries were excised and length-tension curves generated. RESULTS: All vessels were patent in which less than 20% of the length was resected. Clinically, only vessels under extreme tension failed. Length-tension curves suggested 2 zones of vessel extensibility with a breakpoint between them. Extension of the vessel beyond this breakpoint required extreme tension. CONCLUSIONS: Moderate tension at a microarterial anastomosis does not lead to anastomotic failure. Failure occurs after the elastic reserve of the vessel is exceeded.

Anastomosis, Surgical↗

Optimal design of O-to-Z flaps for closure of facial skin defects.

OBJECTIVE: To determine the optimal design of an O-to-Z flap for closure of facial skin defects. METHODS: Prospective cadaver study. Multiple 2-cm-diameter circular skin defects were created in fresh cadavers. Three types of O-to-Z flaps were designed, varying the angle of a curved line about concentric radii of the defect: acute, intermediate, or wide angle flap. The tension of closure of each was measured and compared at different lengths of incision and extents of undermining. RESULTS: The acute angle flap had a significantly lower closing tension at all lengths of incision and extents of undermining than the intermediate and wide angle flaps. Increasing the amount of undermining alone without incising the flap did not significantly decrease the closing tension. Incising the acute angle flap to 4 radii created a nearly tension-free closure. CONCLUSIONS: The optimal design for reducing tension of the O-to Z flap is an acute angle flap. The optimal length of incision and undermining necessary to minimize closing tension is discussed.

Cadaver↗

Snoring and its management.

There are numerous strategies, devices and procedures available to treat snoring. The surgical procedures have an overall success rate of 60-70%, but this probably decreases over time, especially if there is weight gain. There are no long-term rigorously-designed studies comparing the various procedures for decreasing snoring.

Humans↗