Clinical outcomes following intraoperative pedicle disruption in fibula free flaps

OBJECTIVES

Iatrogenic injury of the fibula free flap pedicle is rare. Postoperative flap survival and reconstructive outcomes following intraoperative pedicle severance are unknown. This study assesses free flap outcomes following accidental severance of the peroneal vessels.

METHODS

Multi-institutional retrospective chart review from 2000 to 2020.

RESULTS

Of 2975 harvested fibula free flaps, 26 had a history of pedicle severance during surgical reconstruction. Reasons for intraoperative pedicle severance included transection during muscular dissection 10/26 (39%), accidental severance with the bone saw 12/26 (46%), and other 4/26 (15.6%). The surgeon responsible for pedicle severance included residents 5/26 (19%), fellows 10/26 (39%), attendings 10/26 (39%), and unknown 1/26 (3.9%). The pedicle artery and vein were severed 10/26 (39%), artery 8/26 (31%), and vein 8/26 (31%). Truncated pedicle vessels were used 3/26 (11.7%), intraoperative anastomoses were performed 23/26 (89%). Postoperative revision in the OR within 7 days of surgery was required 6/26 (23%); 4 flaps were salvaged and 2 flaps failed, both arterial thrombosis. Flap failure was attributed to vascular thrombosis. Long-term flap survival and successful reconstructions were reported 24/26 (92%).

CONCLUSION

Accidental severance of fibula free flap pedicle vessels can be corrected with intraoperative repair, without affecting long-term flap survival or reconstructive outcomes. Protecting the flap vessels while using the bone saw and during intramuscular dissection prevents accidental severance.

Extent of Extranodal Extension in Oral Cavity Squamous Cell Carcinoma is Not Independently Associated With Overall or Disease-Free Survival at a 2.0-mm Threshold

PURPOSE

The presence of extranodal extension (ENE) conveys a poor prognosis in oral cavity squamous cell carcinoma (OSCC); however, there is no consensus regarding whether the histopathologic extent of ENE (e-ENE) may be a more discriminating prognostic indicator. The purpose of this study was to assess the impact of minor ENE (<2.0 mm) versus major ENE (≥ 2.0 mm) on overall survival (OS) and disease-free survival (DFS) in OSCC.

MATERIALS AND METHODS

A single-institution, retrospective cohort study was designed using an electronic medical record review. Inclusion criteria included patients with OSCC and cervical node metastasis. All subjects were treated between the years 2009 and 2017 in the Michigan Medicine Department of Oral and Maxillofacial Surgery (Ann Arbor, Michigan). The primary predictor variable was e-ENE, measured as the maximum distance of tumor invasion into extranodal tissue from the outer aspect of the nodal capsule. Primary outcome variables were OS and DFS. Other covariates included demographic data, tumor staging, and histopathologic data. Descriptive statistics were performed. Kaplan-Meier survival plots for OS and DFS were performed. The data were mined for an alternative threshold at which e-ENE may impact survival using Cox proportional hazards models.

RESULTS

One hundred sixty eight subjects were included (91 ENE-negative, 48 minor ENE, and 29 major ENE). Most subjects were male (62%) and the mean age was 62.9 years. Mean follow-up time was 2.97 +/- 2.76 years. There was no statistically significant difference in OS or DFS between minor and major ENE. Five-year OS for minor ENE was 30.4% versus 20.7% for major ENE (P = .28). Five-year DFS for minor ENE was 26.7% versus 18.1% for major ENE (P = .30). Five-year OS and DFS was worse for subjects with ENE-positive disease versus ENE-negative disease (OS: 26.9% vs 63.1%, hazard ratio [HR]: 2.70, 95% confidence interval [CI]: [1.77, 4.10], P < .001; DFS: 23.7% vs 59.7%, HR = 2.55, 95% CI [1.71, 3.79], P < .001). At an alternative threshold of 0.9 mm e-ENE, there was greater DFS in subjects with e-ENE 0.1-0.9 mm versus e-ENE > 0.9 (40.6% vs 18.9%, respectively) (HR = 0.49, 95% CI [0.24, 0.99], P = .047).

CONCLUSION

There was no independent association between survival and e-ENE at a 2.0-mm threshold.

Virtual Externship Programs Can Serve as a Viable Alternative to In-Person Externship Experiences in Oral and Maxillofacial Surgery

PURPOSE

The purpose of this study is to describe a model for a virtual externship program in oral-maxillofacial surgery (OMS); to quantify the value of a virtual externship in increasing understanding of the program structure, scope, and commitment to diversity; and to offer qualitative feedback on structural components.

METHODS

A retrospective study was completed comparing dental student perceptions of an OMS program and the virtual externship experience prior to and following an OMS residency virtual externship event. An electronic survey was distributed to registrants and included 25 questions: 5 related to demographics, 17 ascertaining understanding of various components of the residency and perception of virtual externships, and 3 text-based response queries.

RESULTS

Of the 167 attendees, 125 individuals completed the pre-externship survey and 50 completed the postexternship survey for a response rate of 74.8 and 29.9% respectively. Respondents of both surveys included 30 men and 20 women, aged 18 to 34, at various stages of dental school training and of various ethnic backgrounds. All externs reported an interest in participating in virtual externships if offered by OMS programs. Understanding of scope of practice, daily activities of the program and residents, living in Ann Arbor, relationship between residents and with faculty, and program structure demonstrated a significant increase (P < .001). Perceived commitment to diversity and respect for people of different races, cultures, and backgrounds also showed a significant increase following the event (P < .001).

CONCLUSIONS

A virtual externship can successfully duplicate many of the most valuable components of an in-person externship to allow enhanced understanding and interest in the residency program and can incorporate novel components otherwise not possible in an-person externship.

Comparison of Early Oral Cancer Depth of Invasion From the American Joint Committe on Cancer 7th to 8th Edition Criteria. Does the Difference Impact the Accuracy of Clinical Decision Making?

PURPOSE

Depth of invasion (DOI) is an independent predictor of regional metastasis in oral squamous cell carcinoma. Measurement criteria for DOI were modified in the American Joint Committee on Cancer (AJCC) eighth edition. The purpose of this study was to compare DOI AJCC seventh (DOI7) and eighth (DOI8) edition criteria on frozen section accuracy for decisions regarding elective neck dissection (END) in cT1N0 oral squamous cell carcinoma.

PATIENTS AND METHODS

A blinded, retrospective, comparative study of patients who underwent ablative surgery at the University of Michigan was completed. The predictor variable was criteria for DOI measurement. The outcome variables were concordance between DOI7 and DOI8 measurements and accuracy using thresholds for END. Effect of tumor growth pattern and worst pattern of invasion, and the difference between DOI8 on frozen and permanent specimen were assessed.

RESULTS

A total of 30 specimens of T1N0 oral squamous cell carcinoma (16 tongue, 5 alveolus, 5 floor of mouth, 4 buccal mucosa) were included. DOI7 versus DOI8 on frozen and permanent specimen were significantly different (P < .05) but clinically insignificant and highly correlated (r > 0.99, P < .001). One hundred percent concordance between DOI7 and DOI8 was noted on frozen specimen in predicting the need for END when compared with permanent pathology DOI. There was no significant impact of tumor growth pattern or worst pattern of invasion on measurements and no significant difference in DOI on frozen and permanent specimen for DOI8 (P = .68). Excellent agreement between pathologists for all measurements was observed (ICC>0.99, P < 0001).

CONCLUSIONS

High concordance between DOI measurements by AJCC seventh and eighth edition criteria suggests that guidelines for DOI thresholds for END in patients with T1N0 tumors developed using the AJCC seventh edition can be safely applied using AJCC eighth edition criteria. DOI measurement by AJCC 8 criteria on frozen specimen can be used to guide decision-making regarding END, given the high correlation to AJCC 8 permanent DOI measurement.

Is Perineural Invasion a Reasonable Indicator for Neck Dissection in cT1N0M0 Squamous Cell Carcinoma of the Oral Cavity?

PURPOSE

Perineural invasion (PNI) is considered an adverse histological feature in oral squamous cell carcinoma (OSCC). Controversy exists regarding elective neck dissection (END) in cT1N0M0 OSCC with PNI as the only risk factor. The purpose of this study was to evaluate PNI as an indicator for END, as well as its utility when combined with the depth of invasion (DOI) as a second indicator.

PATIENTS AND METHODS

cT1N0M0 (AJCC8) OSCC patients treated from August 1998 to July 2017 in the Department of Oral and Maxillofacial Surgery, University of Michigan (MI), and Beijing Stomatological Hospital, Capital Medical University (BSH) were reviewed. Data from these sites included both prospectively captured data housed in a database and retrospective data.

RESULTS

283 cT1N0M0 OSCC patients were analyzed. The tongue was the most common subsite (56.2%). Ninety-nine (99) patients received END and 184 neck observation. PNI was found in only 8 patients (2.83%) all in the tongue or inferior gingiva. END was performed in 7 of the PNI patients. The mean depth of invasion for tumors with PNI was 3.97 mm, compared to 2.54 mm in tumors without PNI. PNI was statistically correlated with nodal disease (pN+) and extranodal extension (ENE+). After using DOI as a primary indicator for END, no additional PNI patients benefited from END. In addition, only 2 patients had PNI identified preoperatively both with 5 mm DOI, and therefore, already indicated for END on the basis of DOI status.

CONCLUSIONS

PNI status is statistically correlated with pN+ and ENE + pathology in cT1N0M0 OSCC. After using DOI as a primary indicator for END, PNI status had no added value in decision making. Even surgeons who do not use DOI will find very limited value in PNI status with less than 1% preoperative prevalence (0.71%) in this patient population.

Effect of α2‑macroglobulin in the early stage of jaw osteoradionecrosis

Advanced osteoradionecrosis (ORN) is one of the most serious complications in patients with head and neck cancer, resulting in poor prognosis. Numerous studies have therefore focused on the pathogenesis and interventions of ORN early stage. The present study aimed to investigate whether α2-macroglobulin (α2M) could prevent early-stage jaw osteoradionecrosis caused by radiotherapy (RT). Following local injection of α2M, a single dose of 30 Gy was delivered to rats for pathological exploration. For 28 days, the irradiated mandible and soft tissues were examined for potential changes. Furthermore, primary human bone marrow mesenchymal stem cells pretreated with α2M followed by 8 Gy irradiation (IR) were also used. Tartrate-resistant acid phosphatase assay, terminal uridine deoxynucleotidyl nick end labeling assay and immunohistochemical staining were performed on irradiated mandibular bone, tongue or buccal mucosa tissues from rats. Cell proliferation was assessed by evaluating the cell morphology by microscopy and by using the cell counting kit-8. Fluorescence staining, flow cytometry and western blotting were conducted to detect the reactive oxygen species level, cell apoptosis and protein expression of superoxide dismutase 2 (SOD2), heme oxygenase-1 (HO-1) and phosphorylated Akt following irradiation. The results demonstrated that α2M attenuated physical inflammation, osteoclasts number and fat vacuole accumulation in mandibular bone marrow and bone marrow cell apoptosis following IR in vivo. Furthermore, α2M pretreatment suppressed the expression of 8-hydroxy-2′-deoxyguanosine in mandibular bone and tongue paraffin embedded sections, which is a marker of oxidative damage, and increased SOD2 expression in mucosa and tongue paraffin embedded sections. The present study demonstrated the efficient regulation of antioxidative enzymes, including SOD2 and heme oxygenase-1, and reduction in oxidative damage by α2M. In addition, in vitro results confirmed that α2M may protect cells from apoptosis and suppress reactive oxygen species accumulation. Overall, the present study demonstrated that α2M treatment may exert some radioprotective effects in early-stage ORN via antioxidant mechanisms, and may therefore be considered as a potential alternative molecule in clinical prophylactic treatments.

Oral Lichen Planus-Associated Oral Cavity Squamous Cell Carcinoma Is Associated With Improved Survival and Increased Risk of Recurrence

PURPOSE

We investigated the overall survival (OS), disease-specific survival (DSS), and disease-free survival among patients with oral lichen planus-associated oral cavity squamous cell carcinoma (OLP-OCSCC). The secondary objective was to assess the annual risk of tumor recurrence or second primary tumor (SPT).

MATERIALS AND METHODS

A comparative retrospective study was performed of patients with OLP-OCSCC presenting between June 2007 and December 2018 to the Department of Oral and Maxillofacial Surgery, Michigan Medicine (Ann Arbor, MI) and patients with OCSCC in the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database (1973 to 2015).

RESULTS

A total of 87 patients with OLP-OCSCC met the inclusion criteria, and 55,165 patients with OCSCC from the SEER database were included. The proportion of women was greater in the OLP group than in the SEER group (56.3 vs 38.0%; P < .001). In the OLP group, 47.1% had no smoking history and 43.7% had no alcohol history. Most patients in the OLP group had presented with stage I disease (46.0%) compared with 31.7% in the SEER group (P = .004). Overall, the OS and DSS were significantly greater in the OLP group than in the SEER group at all points from 1 to 5 years (P ≤ .01). In the OLP group, 46 patients (52.9%) had at least 1 recurrence or SPT. At 10 years, the predicted mean number of recurrences was 1.93 per patient (95% confidence interval, 1.56 to 2.39).

CONCLUSIONS

OLP-OCSCC frequently affects women, nonsmokers, and nondrinkers and presents with localized disease at a high frequency. Patients with OLP-OCSCC have increased OS and DSS and a greater risk of tumor recurrence or SPT compared with OCSCC in the general population. Lifelong, frequent surveillance is recommended for patients with OLP-OCSCC owing to the risk of late recurrence. Future studies are needed to understand the pathophysiology of OLP-OCSCC.

High prevalence and incidence of tuberculosis in people living with the HIV in Mandalay, Myanmar, 2011-2017

SETTING

Two human immunodeficiency virus (HIV) clinics providing antiretroviral therapy (ART), Mandalay, Myanmar.

OBJECTIVE

To assess prevalent TB at enrolment, incident TB during follow-up and associated risk factors in adult people living with HIV (PLHIV) between 2011 and 2017.

DESIGN

Cohort study using secondary data.

RESULTS

Of 11 777 PLHIV, 2911 (25%) had prevalent TB at or within 6 weeks of enrolment. Independent risk factors for prevalent TB were being male or single/widowed, daily alcohol consumption, CD4 count 200 cells/μl and anaemia. During 6 years follow-up in 8866 PLHIV with no prevalent TB, the rate of new TB was 2.9 per 100 person-years (95%CI 2.6-3.1). Cumulative TB incidence was 9.6%, with 370 (72%) of 517 new TB cases occurring in the first year. Independent risk factors for incident TB were being male and anaemia. Incident TB was highest in the first year of ART, in PLHIV with CD4 counts 200 cells/μl and those not receiving isoniazid preventive therapy (IPT). Incident TB declined with time on ART and rising CD4 counts.

CONCLUSION

Prevalent and incident TB were high in PLHIV in the Mandalay clinics. Consideration should be given to earlier TB diagnosis using more sensitive diagnostic tools, effective ART and scaling up IPT.

IPT in people living with HIV in Myanmar: a five-fold decrease in incidence of TB disease and all-cause mortality

SETTING

Myanmar, a country with a high human immunodeficiency virus-tuberculosis (HIV-TB) burden, where the tuberculin skin test or interferon-gamma release assays are not routinely available for the diagnosis of latent tuberculous infection.

OBJECTIVE

To assess the effect of isoniazid (INH) preventive therapy (IPT) on the risk of TB disease and mortality among people living with HIV (PLHIV).

DESIGN

A retrospective cohort study of routinely collected data on PLHIV enrolled into care between 2009 and 2014.

RESULTS

Of 7177 patients (median age 36 years, interquartile range 31-42; 53% male) included in the study, 1278 (18%) patients received IPT. Among patients receiving IPT, 855 (67%) completed 6 or 9 months of INH. Patients who completed IPT had a significantly lower risk of incident TB than those who never received IPT (adjusted hazard ratio [aHR] 0.21, 95%CI 0.12-0.34) after controlling for potential confounders. PLHIV who received IPT had a significantly lower risk of death than those who never received IPT (PLHIV who completed IPT, aHR 0.25, 95%CI 0.16-0.37; those who received but did not complete IPT, aHR 0.55, 95%CI 0.37-0.82).

CONCLUSION

Among PLHIV in Myanmar, completing a course of IPT significantly reduced the risk of TB disease, and receiving IPT significantly reduced the risk of death.

Intraoperative Depth of Invasion Is Accurate in Early-Stage Oral Cavity Squamous Cell Carcinoma

PURPOSE

Depth of invasion (DOI) is one predictor of nodal metastasis in oral cavity squamous cell carcinoma (OCSCC) and can facilitate the decision to complete an elective neck dissection (END) in early-stage disease with a clinically negative neck. The purpose of this study was to investigate the accuracy of DOI in intraoperative frozen specimens for T1N0 oral OCSCC.

MATERIALS AND METHODS

To compare the accuracy of DOI in frozen versus permanent specimens, we completed a prospective, blinded study of 30 patients with cT1N0 OCSCC who presented between October 2016 and December 2017.

RESULTS

DOI in frozen specimens was 96.8% accurate in predicting the need for END with a sensitivity of 90.9%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 95.2%. A strong correlation was found between DOIs in frozen and permanent specimens measured by head and neck (HN) pathologists (r = 0.96; 95% confidence interval [CI], 0.93 to 0.97), between HN pathologists using frozen specimens (r = 0.98; 95% CI, 0.95 to 0.99) and permanent specimens (r = 0.95; 95% CI, 0.91 to 0.98), and in DOIs in frozen specimens communicated intraoperatively versus measured by HN pathologist 1 (r = 0.93; 95% CI, 0.86 to 0.97) and HN pathologist 2 (r = 0.95; 95% CI, 0.89 to 0.98). Only 1 patient who did not undergo an END based on frozen specimens was undertreated owing to upgrading of the DOI in permanent specimens.

CONCLUSIONS

DOI in intraoperative frozen sections has an accuracy of 96.8% and may be reliably used as a clinical tool to determine the need for END in early-stage OCSCC.

Diagnosis and Management of Children With Mycobacterium abscessus Infections in the Head and Neck

PURPOSE

Controversy exists regarding the most appropriate treatment strategy for children with nontuberculous mycobacterial (NTM) cervical lymphadenitis. Mycobacterium abscessus (MAB) is an uncommon cause of NTM cervical lymphadenitis. The purpose of the present study was to evaluate diagnosis, management, and treatment outcomes in children with MAB-associated cervical lymphadenitis resulting from a pulpotomy.

MATERIALS AND METHODS

This was a retrospective chart review of children with NTM lymphadenitis of the head and neck caused by MAB treated at Children's Healthcare of Atlanta hospitals (Atlanta, GA). The predictor variables were patient demographics, dental history, clinical presentation, imaging characteristics, laboratory findings, histopathologic examination, treatment, and complications. The outcome variable was disease resolution or persistence.

RESULTS

Twenty-two patients (mean age, 6.5 yr) met the inclusion criteria. All patients had pulpotomy at 1 dental practice. The mean time from dental procedure to symptom onset was 43.1 days (range, 3 to 180 days). Children presented with cervical or submandibular swelling, facial swelling, gingival erythema, and skin erythema. Radiographic findings were submandibular or cervical lymphadenitis, maxillary or mandibular osteolysis, subcutaneous abscess, and pulmonary nodules. All children had confirmed or probable MAB infection diagnosed on the pathologic specimen. There were 2 distinct patient presentations that guided surgical management: isolated noninflammatory cervical lymphadenitis, which was partly or completely excised (n = 11), and adjacent extension or disseminated infection requiring subtotal lymph node excision, bone debridement, and postoperative antibiotics (n = 11). Most children required multiple surgical interventions to remove infected tissues. All achieved clinical resolution.

CONCLUSION

In this cohort, treatment of NTM lymphadenitis caused by MAB depended on extent of disease and virulence of bacteria. When complete surgical excision was possible, disease resolution was achieved. However, in cases with adjacent extension or dissemination infection, postoperative antibiotics were necessary.

Mandibular fractures treated with small plates and screws reduce treatment cost

PURPOSE

The efficacy of treating mandibular fractures with open reduction and internal fixation (ORIF) using small titanium plates and monocortical screws is well established. The purpose of this study was to determine whether the use of semirigid (small) titanium plates results in lower treatment charges.

PATIENTS AND METHODS

Consecutive patients with mandibular fractures were randomly allocated to ORIF with small or large titanium plates. The primary predictor variable for this secondary subset analysis was plate size. The primary outcome variable was total treatment charges. Other outcomes included length of stay (LOS), operating room charges, hardware charges, LOS charge, and charges related to the treatment of complications.

RESULTS

A total of 127 consecutive patients were enrolled in the study. Fifty-two patients completed the required 6-week follow-up and had data available for analysis. Adjusted total treatment charges suggested a significant difference, with a mean total treatment charge of $15,308 in the semirigid group and a mean total treatment charge of $16,557 in the rigid group (P = .04). Total treatment charges were 8% higher in the rigid group compared with the semirigid group.

CONCLUSIONS

The findings of this study suggest that the overall charges associated with treating mandibular fractures with ORIF are significantly lower when semirigid plates are used.

Evaluation of ocular hazards from 4 types of curing lights

OBJECTIVE

To assess the risk of ocular damage from 4 types of light curing units (LCUs) and to estimate the maximum permissible ocular exposure times from each LCU during an 8-hour workday.

METHODS

Extracted human maxillary teeth were mounted in a dentoform. Four types of LCUs (plasma arc, low-power and high-power light-emitting diode, and quartz-tungsten-halogen) were used to cure a simulated restoration in the maxillary central incisor from the facial and palatal aspects. To simulate ocular exposure, the spectral irradiance (W/[cm2 · nm]) from the LCUs was measured 5 times at each of 3 distances (30 cm, 50 cm and 100 cm) from the tooth, using a cosine-corrected probe attached, via a fibre optic cable, to a calibrated spectroradiometer. The weighted blue-light and effective ultraviolet (UV) irradiances that would be received by the eye from each LCU were calculated.

RESULTS

The maximum permissible daily exposure limits for UV light exceeded 8 hours at all distances and orientations. The maximum permissible cumulative daily exposure time to blue light was as low as 6 seconds when curing from the palatal aspect with the plasma arc LCU and as high as 1.5 hours when the low-power light-emitting diode LCU was used from the facial aspect.

CONCLUSIONS

The 4 LCUs tested did not pose a risk of UV-mediated ocular damage. The higher-powered lamps showed potential to cause blue-light-mediated ocular damage at shorter distances, with damage potentially occurring after cumulative viewing of only 6 seconds at the 30-cm distance during an 8-hour workday.

The mysteries and demands of HIV care: qualitative analyses of HIV specialists’ views on their expertise

To deepen our understanding of the mysteries and demands associated with HIV care and to inform the debate about HIV specialization, we conducted in-depth interviews with a purposive sample of 20 identified HIV specialists in the San Francisco Bay Area. Participants were from several medical specialties and reported a median of 50% of their time spent in HIV patient care. Through constant comparison, a template of open codes was constructed to identify themes that emerged from the data. Data were analyzed according to the conventions of qualitative research and revealed six interrelated themes: (1) coping with uncertainty and rapid change: being 'comfortable with mystery'; (2) the powerful role of experience; (3) the dual faces of knowledge: 'knowing the patient' and 'knowing the facts'; (4) the dual faces of passion: challenge and calling; (5) stress and burnout; and (6) the relationship between academia and 'the trenches'. The themes underscore the dual dimensions of HIV care: providers must interweave the 'half-baked' science about drug therapies, side effects and drug interactions with the psychosocial and lifestyle factors of the patient. They also provide insight into quantitative findings linking greater HIV experience with better patient outcomes and suggest that providers need skills associated with generalist and specialist training, a phenomenon that argues for a 'special' specialty for HIV care.

MC1R variants correlate with thinhorn sheep colour cline but not individual colour

The melanocortin 1 receptor (MC1R) gene has provided a window on the evolution of colour polymorphisms. Recent studies have demonstrated associations between MC1R and melanism in a number of wildlife species. Thinhorn sheep ( Ovis dalli Nelson, 1884) are a possible species to test for association between MC1R polymorphisms and melanism. Across their range the pelage colour of thinhorn sheep intergrades between all white phenotypes to very dark phenotypes. Most thinhorn sheep are white; however, there is a 1200 km cline from light to dark sheep that occurs over three genetically distinct polymorphic populations. We sequenced the entire MC1R gene from 40 individuals across the range of thinhorn sheep. We found a single nucleotide polymorphism in MC1R at base pair position 921 that coincided with the geographic cline. However, at the individual level we found no relationship between individual melanism and genotype.

Dose-response relationship of rocuronium: a comparison of electromyographic vs. acceleromyographic-derived values

BACKGROUND

Acceleromyography (AMG) is being employed with increasing frequency as a research tool. However, there is almost no information available regarding the accuracy of values for drug potency obtained using AMG. This study was an attempt to determine if AMG-derived ED(50/95) values are interchangeable with those measured with a more traditional neuromuscular monitor.

METHODS

Thirty adult patients were studied. Anesthesia was induced and maintained with N20, propofol, and supplementation opioid. Tracheal intubation was accomplished without muscle relaxants. Simultaneous ipsilateral AMG and EMG responses to 0.10 Hz stimulation was recorded. Following instrument calibrations, a single dose of rocuronium was administered. The first patient received a bolus of 0.17 mg kg(-1) of rocuronium. Using the Hill equation with a postulated slope of 4.50, the ED(50) was calculated. The second subject received a dose which approximated the calculated ED(50) for patient no. 1. Successive subjects were given a dose based on the running average of the estimated ED(50).

RESULTS

The AMG-derived ED50/95 values for rocuronium (0.163 +/- 0.055 and 0.314 +/- 0.105 mg mg(-1)) were virtually identical to those established using EMG (0.159 +/- 0.043 and 0.306 +/- 0.084 mg kg(-1)). While mean peak twitch depression (Delta T1) was the same in both groups for individual subjects Delta T1 differed by +/- 20% (95% confidence interval).

DISCUSSION

Acceleromyography-derived twitch heights for individual patients are not necessarily interchangeable with information obtained using electromyography. Nevertheless, acceleromyography appears to be a valid methodology for determining the drug potency when a population rather than an individual subject is being studied.

Interventions that help victims of domestic violence. A qualitative analysis of physicians' experiences

BACKGROUND

The barriers physicians face when providing care to victims of domestic violence are well detailed in the literature, but few studies provide insight into how physicians overcome these barriers. Our goal was to describe the domestic violence interventions used by physicians who are committed to providing quality health care to battered women.

METHODS

We conducted 6 focus groups with 45 San Francisco Bay Area physicians who had intervened with victims of domestic violence. The sessions were audiotaped and transcribed. We constructed, through constant comparison, a template of open codes to identify themes that emerged from the data.

RESULTS

Our analysis revealed that physicians viewed validation (ie, providing messages to the patients that they are worth caring about) as the foundation of intervention. Other interventions included labeling the abuse as abuse; listening and being nonjudgmental; documenting, referring, and safety planning; using a team approach; and prioritizing domestic violence in the health care environment. Physicians described a range of rewards for intervening with victims, from seeing a patient change her entire life to subtle shifts in the way a woman thinks of her relationship and herself.

CONCLUSIONS

Our study offers insight into how physicians can intervene to help victims of domestic violence. Recent interview and survey studies of battered women support the physician interventions described.

A qualitative analysis of how physicians with expertise in domestic violence approach the identification of victims

BACKGROUND

Physicians have been called upon to identify victims of domestic violence, but few studies provide insight into how physicians can navigate around the barriers to identification.

OBJECTIVE

To describe how physicians who are committed to helping battered patients identify victims of domestic violence in health care encounters.

DESIGN

Six focus groups were conducted.

SETTING

Focus group research facilities.

PARTICIPANTS

45 emergency department, obstetrician/ gynecologist, and primary care physicians in the San Francisco Bay Area who identify and intervene with victims of domestic violence.

MEASUREMENTS

Through constant comparison, a template of open codes was constructed to identify themes that emerged from the data. Data were analyzed according to the conventions of qualitative research.

RESULTS

The data revealed five major themes: 1) how physicians framed screening questions to reduce patient discomfort; 2) patient signs that "switched on a light bulb" for physicians to suspect abuse; 3) direct and indirect approaches to identification, with an emphasis on facilitating patient trust and disclosure over time; 4) the rarity of direct patient disclosure; and 5) how physicians redefined successful outcomes of universal screening. Physicians also described two new barriers to screening: mandatory reporting and "burnout" due to lack of direct disclosure.

CONCLUSIONS

Identifying domestic abuse is difficult even for physicians committed to helping victims. Physician reports illustrate the need to frame questions and develop indirect approaches that foster patient trust. Given the many barriers to screening and the rarity of direct patient disclosure, it may be more productive to redefine the goals of universal screening so that compassionate asking in and of itself constitutes the first step in helping battered patients.

When asked, patients tell: disclosure of sensitive health-risk behaviors

OBJECTIVES

National health care organizations recommend routinely screening patients for behavioral health risks, the effectiveness of which depends on patients' willingness to disclose risky behaviors. This study aimed to determine if primary care patients' disclosures of potentially stigmatizing behaviors would be affected by (1) their expectation about whether or not their physician would see their disclosures and (2) the assessment method.

METHODS

One thousand nine hundred fifty-two primary care patients completed a questionnaire assessing human immunodeficiency virus (HIV), alcohol, drug, domestic violence, tobacco, oral health, and seat belt risks; half were told their responses would be seen by the researcher and their physician and half were told that their responses would be seen by the researcher only. Patients were randomly assigned to one of five assessment methods: written, face-to-face, audio-based, computer-based, or video-based.

RESULTS

Across all risk areas, patients did not disclose differently whether or not they believed their physician would see their disclosures. Technologically advanced assessment methods (audio, computer, and video) produced greater risk disclosure (4%-8% greater) than traditional methods in three of seven risk areas.

CONCLUSIONS

These findings suggest patients are not less willing to disclose health risks to a research assistant knowing that this information would be shared with their physician and that a number of assessment methods can effectively elicit patient disclosure. Potentially small increases in risk disclosure must be weighed against other factors, such as cost and convenience, in determining which method(s) to use in different health care settings.

Leukemia induced in rats but not mice by dimethyl morpholinophosphoramidate, a simulant anticholinesterase agent

Dimethyl morpholinophosphoramidate (DMMPA), an organophosphate, caused leukemia in male and female Fischer 344/N rats. DMMPA was administered in corn oil by oral intubation to groups of 50 male and 50 female rats at 0, 150, 300, or 600 mg/kg body weight, five times per week for 2 years. B6C3F1 mice were given 0, 150 (males only), 300, and 600 (females only) mg/kg body weight under the same schedule. DMMPA induced a dose-related enhancement in the incidence of mononuclear cell leukemia in rats--males: controls = 14/50, 150 mg group = 21/50; 300 mg group = 19/50; 600 mg group = 25/50; females: controls = 9/50, 150 mg group = 13/50; 300 mg group = 12/49; 600 mg group = 18/50. Survival-adjusted rates strengthen the DMMPA effect: males--31%, 50%, 47%, and 63%; females--20%, 32%, 30%, 50%. Latent periods for mononuclear cell leukemia development in exposed rats were not shortened compared to controls. No carcinogenic effects in mice were detected. DMMPA was not mutagenic in Salmonella, was mutagenic for mouse lymphoma cells, and induced both chromosome aberrations and sister chromatid exchanges in Chinese hamster ovary cells.

Effects on the murine mononuclear phagocyte system of chronic administration of liposomes containing cytotoxic drug or lipid A compared with empty liposomes

In experiments designed to examine the adverse effects of chronic liposome administration in vivo on the mononuclear phagocyte system (reticuloendothelial system), the presence of drug entrapped in the liposomes may increase the level of reticuloendothelial impairment. We have compared the effects on the mononuclear phagocyte system in mice of chronic administration of empty liposomes with the effects of liposomes containing the anti-leishmanial drug meglumine antimoniate. We have also examined the effect on the mononuclear phagocyte system of continued injections of liposomes containing lipid A, a component of bacterial lipopolysaccharide, which is responsible for macrophage activation. Ten intravenous injections of multilamellar liposomes composed of dipalmitoylphosphatidylcholine and cholesterol (1:0.75 M ratio) were given to ICR mice over a 25-day period. Two individual groups of mice received endotoxin-free liposomes in which meglumine antimoniate was either present or absent. One addition group received liposomes containing lipid A derived from Escherichia coli lipopolysaccharide. A control group received sterile saline injections. In each group, a depression of the phagocytic index, as measured by reduction of uptake of particulate carbon, was observed among some of the individual animals 24 h after the first injection. In many mice a marked splenomegaly was observed. A depressed phagocytic index and splenomegaly were most marked for mice receiving lipid A liposomes. However, there was a large individual variability among mice receiving these preparations and some mice in each group had normal spleen size and a nearly normal phagocytic index. Tissue distribution of liposomes containing [14C]dipalmitoylphosphatidylcholine as a phospholipid marker was examined in all groups in mice 24 h after the last injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Scheuermann kyphosis. Follow-up of Milwaukee-brace treatment

From 1960 through 1978, a total of 274 patients who had a diagnosis of Scheuermann kyphosis were treated with a Milwaukee brace at the Twin Cities Scoliosis Center. We analyzed the long-term results in 120 patients who had used the Milwaukee brace and had been followed for at least five years after the completion of treatment. The average age of the patients at the initiation of treatment was twelve years and five months, the average age at the completion of treatment was sixteen years and one month, and the average age at the last follow-up examination was twenty-four years. Of the patients who wore the brace consistently, seventy-six showed improvement in the kyphosis between the initial evaluation and the evaluation at final follow-up, while twenty-four showed worsening and ten were unchanged. Seven of the twenty-four patients who were worse had had surgery before the review for this study. The indication for surgery was a kyphosis of more than 60 degrees that was increasing and was not controlled by the brace. Ten patients were inconsistent in their use of the brace. Two of the ten patients had improvement and eight had worsening of the kyphosis; three of the latter eight had a spinal fusion. This study showed that the Milwaukee brace is usually an effective method of treatment for patients who have Scheuermann kyphosis; however, four of fourteen patients who had an initial kyphosis of more than 74 degrees required a spinal fusion.

Ontogeny of immunity and leukocytes in the ovine fetus and elevation of immunoglobulins related to congenital infection

Certain humoral and cellular aspects of the immune response were observed during gestation in the ovine fetus. Emergence and development of leukocytes in peripheral blood were observed. Morphologically mature lymphocytes were consistently present at 32 days of gestation, but mature neutrophils were not neutrophils were not consistently present until gestational day 123. Monocytes were first observed at 63 days and eosinophils at 112 days of gestational age. Numbers of each class of leukocyte increased from the time of their appearance until just prior to birth when they declined. Production of immunoglobulin G (IgG) and immunoglobulin M (IgM) was monitored from the time of their appearance at 56 and 77 days, respectively, until birth. In contrast to consistently low base-line values of IgG and IgM (below 0.22 mg/ml and 0.21 mg/ml, respectively) found in clinically normal, unstimulated fetuses, the immunoglobulin values in experimentally infected animals increased with the age of the fetus. This finding can be utilized in diagnosis of several congenital infections and anomalies.