Nasal Intubation is not Associated with "Smoother" Emergence from General Anesthesia for Carotid Endarterectomy: A Case-Cohort Study

BACKGROUND

Postoperative hematoma after carotid endarterectomy (CEA) is a devastating complication and may be more likely in patients with uncontrolled hypertension and coughing on emergence from anesthesia. We sought to determine if intubation with a nasal endotracheal tube (ETT)-instead of an oral ETT-is associated with "smoother" (i.e., less hemodynamic instability) emergence from general anesthesia for CEA.

METHODS

Patients receiving CEA between December 2015 and September 2021 at a single tertiary academic medical center were included. We examined the electronic anesthesia records for 323 patients who underwent CEA during the 6-year study period and recorded consecutive systolic blood pressure (SBP) values during the 10 minutes before extubation as a surrogate for "smoothness" of the emergence.

RESULTS

Intubation with a nasal ETT, when compared with intubation with an oral ETT, was not associated with any difference in maximum, minimum, average, median, or standard deviation of serial SBP values in the 10 minutes before extubation. The average SBP on emergence for patients with an oral ETT was 141 mm Hg and with a nasal ETT was 144 mm Hg (P = 0.562). The maximum SBP for patients with oral and nasal ETTs were 170 mm Hg and 174 mm Hg, respectively (P = 0.491). There were also no differences in the qualitative "smoothness" of emergence or in the percentage of patients who required an intravenous dose of 1 or more antihypertensive medications. The incidence of postoperative complications was similar between the 2 groups.

CONCLUSIONS

When SBP is used as a surrogate for smoothness of emergence from general anesthesia for CEA, intubation with a nasal ETT was not associated with better hemodynamic stability compared to intubation with an oral ETT.

Anxiety in a Specialist Perinatal Mental Health Service: patient characteristics, management, and outcomes

OBJECTIVES

To outline characteristics of patients with anxiety diagnoses attending a Specialist Perinatal Mental Health Service (SPMHS) in Ireland, the mental health care received by those patients, mental health and obstetric outcomes for those patients, and immediate neonatal outcomes for their babies.

METHODS

A retrospective chart review was conducted of patients with antenatal anxiety diagnoses who attended the SPMHS in University Maternity Hospital Limerick, from initiation of the service to the end of its first year.

RESULTS

Data were collected on 100 patients, 81 with a mental health diagnosis prior to attending the SPMHS, 32 with prior engagement with psychiatry, and 23 with a previous perinatal diagnosis. The mean age of patients was 32.4 (19-47, std 6.158). Beyond initial assessment, the Mental Health Midwife was involved in the care of 61% of patients, more than any other specialty including psychiatry. Twenty-seven patients had psychiatric medication either started or altered by the SPMHS. The most common reason for eventual discharge was that patients were well. Two patients presented in mental-health-related crisis to emergency services and one patient was admitted to an acute psychiatric ward.

CONCLUSIONS

Patients attending the SPMHS for anxiety spanned a broad spectrum of demographics and diagnoses and received varied set of interventions. A significant proportion of patients had a primary diagnosis of Pregnancy-related anxiety. The Mental Health Midwife played a key role in management of these patients. Though rates of mental health crises and admissions were low, the absence of a Mother and Baby Unit in Ireland was highlighted.

Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

INTRODUCTION

The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.

METHODS

In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.

FINDINGS

Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.

INTERPRETATION

After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Early Guided Palliative Care Communication for Patients With COVID-19 Receiving ECMO

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) combined with COVID-19 presents challenges (eg, isolation, anticipatory grief) for patients and families.

OBJECTIVE

To (1) describe characteristics and outcomes of patients with COVID-19 receiving ECMO, (2) develop a practice improvement strategy to implement early, semistructured palliative care communication in ECMO acknowledgment meetings with patients' families, and (3) examine family members' experiences as recorded in clinicians' notes during these meetings.

METHODS

Descriptive observation of guided, in-depth meetings with families of patients with COVID-19 receiving ECMO, as gathered from the electronic medical record of a large urban academic medical center. Most meetings were held within 3 days of initiation of ECMO.

RESULTS

Forty-three patients received ECMO between March and October 2020. The mean patient age was 44 years; 63% of patients were Hispanic/Latino, 19% were Black, and 7% were White. Documentation of the ECMO acknowledgment meeting was completed for 60% of patients. Fifty-six percent of patients survived to hospital discharge. Family discussions revealed 7 common themes: hope, reliance on faith, multiple family members with COVID-19, helping children adjust to a new normal, visitation restrictions, gratitude for clinicians and care, and end-of-life discussions.

CONCLUSION

Early and ongoing provision of palliative care is feasible and useful for highlighting a range of experiences related to COVID-19. Palliative care is also useful for educating patients and families on the benefits and limitations of ECMO therapy.

Impact of Pandemic Response on Training Experience of Anesthesiology Residents in an Academic Medical Center: A Retrospective Cohort Study

Background The impact of the coronavirus disease 2019 (COVID-19) pandemic substantially altered operations at hospitals that support graduate medical education. We examined the impact of the pandemic on an anesthesiology training program with respect to overall case volume, subspecialty exposure, procedural skill experience, and approaches to airway management. Methods Data for this single center, retrospective cohort study came from an Institutional Review Board approved repository for clinical data. Date ranges were divided into the following phases in 2020: Pre-Pandemic (PP), Early Pandemic (EP), Recovery 1 (R1), and Recovery 2 (R2). All periods were compared to the same period from 2019 for case volume, anesthesia provider type, trainee exposure to Accreditation Council for Graduate Medical Education (ACGME) index case categories, airway technique, and patient variables. Results 15,087 cases were identified, with 5,598 (37.6%) in the PP phase, 1,570 (10.5%) in the EP phase, 1,451 (9.7%) in the R1 phase, and 6,269 (42.1%) in the R2 phase. There was a significant reduction in case volume during the EP phase compared to the corresponding period in 2019 (-55.3%; P < .001) that improved but did not return to baseline by the R2 phase (-17.6%; P < .001). ACGME required minimum cases were reduced during the EP phase compared to 2019 data for pediatric cases (age < 12 y, -72.1%; P < .001 and age < 3 y, -53.5%; P < .006) and cardiopulmonary bypass cases (52.3%, P < .003). Surgical subspecialty case volumes were significantly reduced in the EP phase except for transplant surgery. By the R2 phase, all subspecialty volumes had recovered except for plastic surgery (14.9 vs. 10.5 cases/week; P < .006) and surgical endoscopy (59.2 vs. 40 cases/week; P < .001). Use of video laryngoscopy (VL) and rapid sequence induction and intubation (RSII) also increased from the PP to the EP phase (24.6 vs. 79.6%; P < .001 and 10.3 vs. 52.3%; P < .001, respectively) and remained elevated into the R2 phase (35.2%; P < 0.001 and 23.1%; P < .001, respectively). Conclusions The COVID-19 pandemic produced significant changes in surgical case exposure for a relatively short period. The impact was short-lived, with sufficient remaining time to meet the annual ACGME program minimum case requirements and procedural experiences. The longer-term impact may be a shift towards the increased use of VL and RSII, which became more prevalent during the early phase of the pandemic.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

1462 Sarcoma of the Distal Fibula; Presentation of an Anatomical Reconstruction and Literature Review

Introduction

Musculoskeletal tumours affecting the lower limb, and the distal fibula in particular, are rare. Substantial variation exists in both reconstructive techniques employed in their management and reported results; a consequence of their low incidence and the specific challenges presented by the location. Advances in imaging and neo-adjuvant chemotherapy have sparked a paradigm shift in the management of these cases. Where amputation was once the mainstay, limb salvage surgery is now a viable option and multiple techniques exist, but outcomes are poorly studied.

Method

We performed a literature review and report a three-patient case series. All three patients underwent our novel reconstruction technique, utilising a vascularised ipsilateral fibula graft.

Results

102 patient cases of distal fibula resection were identified. 57 of these patients had malignant disease. Evidence that limb salvage surgery produces good functional outcomes for sarcoma patients is limited; 25% of patients with malignant disease were reported as having poor outcomes or disease progression. All three patients undergoing our novel reconstructive technique have had good functional and oncological outcomes.

Conclusions

This is the largest literature review of patients undergoing distal fibula resection. Reconstruction is complex and no single solution exists. We present the use of a vascular proximal ipsilateral fibula graft, which to the best of our knowledge, has not been previously reported. The reconstructive method we present appears to be a durable technique offering an excellent functional outcome and is an appealing alternative to arthrodesis or amputation in appropriate patients.

Head and neck sarcoma: three-year data from a tertiary referral centre

INTRODUCTION

Sarcomas of the head and neck are neoplasms arising from the embryonic mesenchyme. They are rare and heterogeneous in nature and are associated with significant morbidity and mortality. This study evaluates patients referred to the Oxford Sarcoma Service, a tertiary referral centre.

METHODS

Patients discussed over a three-year period were included. Medical records were analysed using the electronic patient record database. Data were acquired on a range of domains, including: demographics, histopathology, treatment modality, recurrence, mortality, survival, etc.

RESULTS

Thirty-two eligible patients, 21 male and 11 female, were identified with a mean age of 58 years; 26 out of 32 patients had high-grade sarcomas. The commonest histological subtype was chondrosarcoma (8/32). Twenty-two underwent planned multidisciplinary team surgical resection after biopsy and staging: negative margins were noted in 9, with close and involved margins in 5 and 8, respectively. Local recurrence was noted in 13 and 6 had metastatic disease out of the 32 eligible patients. Mortality was noted in 10 out of 32 patients. Mean survival was 69.5 months. Five-year overall survival was 64%. Surgery demonstrated statistically significant improvement in survival (p=0.0095). There were no significant differences in survival, recurrence or marginal status between methods of adjuvant or neoadjuvant therapy.

CONCLUSION

Outcomes of head and neck sarcomas are inferior compared with other types of sarcoma. The nature of the complex surrounding anatomy presents unique challenges in surgical management. This in turn affects rates of local recurrence and prognosis. Therefore, it is critical that they are managed in tertiary, specialist centres with a multidisciplinary approach.

Effect of increased serum 25(OH)D and calcium on structure and function of post-menopausal women: a pilot study

The purpose was to determine if increasing serum 25(OH)D and calcium in postmenopausal women increased skeletal muscle size, strength, balance, and functional task performance while decreasing muscle fatigue. PCSA of the vastus lateralis increased and ascent of stairs time decreased after 6 months of increased serum 25(OH)D.

PURPOSE

The Institute of Medicine recommends ≥ 20 ng/ml of serum 25-hydroxyvitamin D [25(OH)D] for bone and overall health. Serum 25(OH)D levels have been associated with physical performance, postural sway, and falls. The purpose of this study was to determine if increasing postmenopausal women's serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml improved skeletal muscle size, strength, balance, and functional performance while decreasing skeletal muscle fatigue.

METHODS

Twenty-six post-menopausal women (60-85 years old) with baseline serum 25(OH)D levels between 20 and 30 ng/ml were recruited. Oral over-the-counter (OTC) vitamin D3 and calcium citrate were prescribed to increase subjects' serum 25(OH)D to levels between 40 and 50 ng/ml, serum calcium levels above 9.2 mg/dl, and PTH levels below 60 pg/ml, which were confirmed at 6 and 12 weeks. Outcome measures assessed at baseline and 6 months included muscle physiological cross-sectional area (PCSA), muscle strength, postural balance, time to perform functional tasks, and muscle fatigue. Repeated measures comparisons between baseline and follow-up were performed.

RESULTS

Nineteen subjects completed the study. One individual could not afford the time commitment for the repeated measures. Three individuals did not take their vitamin D as recommended. Two subjects were lost to follow-up (lack of interest), and one did not achieve targeted serum 25(OH)D. Vastus lateralis PCSA increased (p = 0.007) and ascent of stair time decreased (p = 0.042) after 6 months of increasing serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml. Isometric strength was unchanged. Anterior-posterior center of pressure (COP) excursion and COP path length decreased (p < 0.1) albeit non-significantly, suggesting balance may improve from increased serum 25(OH)D and calcium citrate levels.

CONCLUSIONS

Several measures of muscle structure and function were sensitive to elevated serum 25(OH)D and calcium levels indicating that further investigation of this phenomenon in post-menopausal women is warranted.

Three-dimensional imaging of shear bands in bulk metallic glass composites

The mechanism of the increase in ductility in bulk metallic glass matrix composites over monolithic bulk metallic glasses is to date little understood, primarily because the interplay between dislocations in the crystalline phase and shear bands in the glass could neither be imaged nor modelled in a validated way. To overcome this roadblock, we show that shear bands can be imaged in three dimensions by atom probe tomography from density variations in the reconstructed atomic density, which density-functional theory suggests being a local-work function effect. Imaging of near-interface shear bands in Ti₄₈ Zr₂₀ V₁₂ Cu₅ Be₁₅ bulk metallic glass matrix composite permits measurement of their composition, thickness, branching and interactions with the dendrite interface. These results confirm that shear bands here nucleate from stress concentrations in the glass due to intense, localized plastic deformation in the dendrites rather than intrinsic structural inhomogeneities.

Performance characteristics of a new arterial line filter

A new 40 micron polyester screen arterial line filter with integral automatic blood gas separator has been designed with the potential for improved removal characteristics for gas microbubbles and massive air. A simple in vitro evaluation has been carried out comparing the new filter (Pall EC+) against a standard widely-used reference arterial line filter (Pall EC 3840). The filters have been compared in terms of their haemodynamic performance, specifically pressure drop at incremental flow rates and haemolysis characteristics measuring generated plasma free haemoglobin. In addition, the relative abilities of the test and reference filters to remove gaseous microbubbles, and also to vent massive air introduced into the test circuits have been assessed using an ultrasound based microbubble detection system. The results of the studies indicate that the test and reference filters are identical in terms of haemodynamics, with maximal pressure drops of 30 mmHg at 4-5 litres mean flow rate. Neither filter is associated with significant haemolysis in bovine blood test circuits flowing at 4 I/min for 60 minutes. However, the EC+ filter has significantly superior performance over the reference EC 3840 filter in both microbubble removal and in removal of nitrogen gas introduced directly into the test circuit at up to 5 litres gas/min ( p < 0.01). The new EC+ filter appears to offer safety in terms of haemodynamics and haemolysis, while providing maximal protection against massive arterial gas embolism.

The vascularised fibular graft for limb salvage after bone tumour surgery

Vascularised fibular grafts (VFGs ) are a valuable surgical technique in limb salvage after resection of a tumour. The primary objective of this multicentre study was to assess the risk factors for failure and complications for using a VFG after resection of a tumour.

The study involved 74 consecutive patients (45 men and 29 women with mean age of 23 years (1 to 64) from four tertiary centres for orthopaedic oncology who underwent reconstruction using a VFG after resection of a tumour between 1996 and 2011. There were 52 primary and 22 secondary reconstructions. The mean follow-up was 77 months (10 to 195).

In all, 69 patients (93%) had successful limb salvage; all of these united and 65 (88%) showed hypertrophy of the graft. The mean time to union differed between those involving the upper (28 weeks; 12 to 96) and lower limbs (44 weeks; 12 to 250). Fracture occurred in 11 (15%), and nonunion in 14 (19%) patients.

In 35 patients (47%) at least one complication arose, with a greater proportion in lower limb reconstructions, non-bridging osteosynthesis, and in children. These complications resulted in revision surgery in 26 patients (35%).

VFG is a successful and durable technique for reconstruction of a defect in bone after resection of a tumour, but is accompanied by a significant risk of complications, that often require revision surgery. Union was not markedly influenced by the need for chemo- or radiotherapy, but should not be expected during chemotherapy. Therefore, restricted weight-bearing within this period is advocated.

Cite this article: Bone Joint J 2015;97-B:853–61.

Challenges to delivery of isoniazid preventive therapy in a cohort of children exposed to tuberculosis in Timor-Leste

OBJECTIVES

To evaluate the number and geographic location of children aged <5 years exposed to sputum smear-positive tuberculosis (TB) in Timor-Leste, to determine the proportion evaluated for isoniazid preventive therapy (IPT) and to review the programmatic challenges present in delivering IPT to this cohort.

METHODS

A total of 256 consecutive sputum smear-positive TB index cases diagnosed at Bairo Pite Clinic between August 2013 and July 2014 were interviewed about places of residence and household contacts <5 years of age in the 3 months preceding diagnosis. Attendance of these contacts for screening and the outcome of screening were recorded prospectively.

RESULTS

The majority (225 of 256, 88%) of index cases resided in Dili, but 73 of 225 (32%) of these also had a second address outside the capital. A total of 255 contacts were identified; 172 of 255 (67%) of whom lived in Dili district and 83 of 255 (33%) of whom resided in remote districts. Only 66 of 255 (26%) contacts attended for evaluation for IPT, of whom 46 of 255 (18%) started IPT and nine of 255 (3.5%) were diagnosed with TB. Attendance was significantly less likely when the index case was not the parent of the child contact.

CONCLUSIONS

Sputum smear-positive pulmonary TB cases frequently result in household exposure of children <5 years in Timor-Leste, and provision of IPT is suboptimal. Contacts are located in diverse and distant locations. Further studies to delineate access barriers to IPT and review programmatic models that will facilitate IPT scale up in Timor-Leste are needed.

The treatment of femoral neuropathy due to pseudotumour caused by metal-on-metal resurfacing arthroplasty

Concerns now exist about the long-term biological effects of exposure to orthopaedic metal alloys, particularly serum cobalt and chromium ions derived from metal-on-metal wear debris in these patients. A pseudotumour mass complicating metal-on-metal resurfacing arthroplasty has been recognized by orthopaedic oncologists and specialist hip units. Pseudotumours may also present with a major nerve palsy. Two cases of femoral neuropathy due to pseudotumour masses caused by metal-on-metal resurfacing arthroplasty are presented. Preoperative neurophysiological studies showed severe and irreversible pathological changes to nerve function with neurohistopathological evidence of complete nerve destruction with a previously unreported pathological appearance. This may represent a previously unrecognized pathological process, possibly 'toxic' in nature, resulting from metal-on-metal wear debris. Prolonged follow-up and detailed clinical assessment of patients after hip resurfacing arthroplasty is advocated with planned and expeditious revision of any patient in whom evidence of femoral neuropathy develops.

The role of the popliteofibular ligament and the tendon of popliteus in providing stability in the human knee

Techniques for the selective cutting of ligaments in cadaver knees defined the static contributions of the posterolateral structures to external rotation, varus rotation and posterior tibial translation from 0 degrees to 120 degrees of flexion under defined loading conditions. Sectioning of the popliteofibular ligament (PFL) (group 1) produced no significant changes in the limits of the knee movement studied. Sectioning of the PFL and the popliteus tendon (femoral attachment, group 2) produced an increase of only 5 degrees to 6 degrees in external rotation from flexion of 30 degrees to 120 degrees (p < 0.001). Even when other ligaments were sectioned first (group 3), the maximum effect of the PFL was negligible. Our findings show that the popliteus muscle-tendon-ligament complex, lateral collateral ligament, and posterolateral capsular structures function as a unit. No individual structure alone is the primary restraint for the movements studied. Operative reconstruction should address all of the posterolateral structures, since restoration of only a portion may result in residual instability.

A mobile-bearing total knee prosthesis compared with a fixed-bearing prosthesis. A multicentre single-blind randomised controlled trial

Before proceeding to longer-term studies, we have studied the early clinical results of a new mobile-bearing total knee prosthesis in comparison with an established fixed-bearing device. Patients requiring bilateral knee replacement consented to have their operations under one anaesthetic using one of each prosthesis. They also agreed to accept the random choice of knee (right or left) and to remain ignorant as to which side had which implant. Outcomes were measured using the American Knee Society Score (AKSS), the Oxford Knee Score (OKS), and determination of the range of movement and pain scores before and at one year after operation. Preoperatively, there was no systematic difference between the right and left knees. One patient died in the perioperative period and one mobile-bearing prosthesis required early revision for dislocation of the meniscal component. At one year the mean AKSS, OKS and pain scores for the new device were slightly better (p < 0.025) than those for the fixed-bearing device. There was no difference in the range of movement. We believe that this is the first controlled, blinded trial to compare early function of a new knee prosthesis with that of a standard implant. It demonstrates a small but significant clinical advantage for the mobile-bearing design.

Decreased nuclear factor-kappaB DNA binding activity following permanent focal cerebral ischaemia in the rat

Many factors implicated in the pathogenesis of cerebral ischaemia such as glutamate, tumour necrosis factor and interleukin-1 have also been shown to activate nuclear factor-kappaB (NF-kappaB). In the present study we have investigated NF-kappaB activity at various times following permanent focal cerebral ischaemia in rats using immunohistochemistry, western blotting and electrophoretic mobility shift assay (EMSA). Three hours following middle cerebral artery occlusion nuclear translocation of NF-kappaB was detected using immunohistochemical and western blotting techniques. This was reflected in a trend towards increased NF-kappaB binding activity (EMSA) in the ischaemic cortex compared to histologically normal tissue. In contrast however, from 6 to 48 h post-occlusion nuclear translocation and NF-kappaB binding activity was decreased in the ischaemic cortex. Decreased NF-kappaB binding activity detected in degenerating neurones, suggests that decreased NF-kappaB activity may exacerbate ischaemia induced neuronal cell death.

Science's new social contract with society

Under the prevailing contract between science and society, science has been expected to produce 'reliable' knowledge, provided merely that it communicates its discoveries to society. A new contract must now ensure that scientific knowledge is 'socially robust', and that its production is seen by society to be both transparent and participative.

An encyclopedia of mouse genes

The laboratory mouse is the premier model system for studies of mammalian development due to the powerful classical genetic analysis possible (see also the Jackson Laboratory web site, http://www.jax.org/) and the ever-expanding collection of molecular tools. To enhance the utility of the mouse system, we initiated a program to generate a large database of expressed sequence tags (ESTs) that can provide rapid access to genes. Of particular significance was the possibility that cDNA libraries could be prepared from very early stages of development, a situation unrealized in human EST projects. We report here the development of a comprehensive database of ESTs for the mouse. The project, initiated in March 1996, has focused on 5' end sequences from directionally cloned, oligo-dT primed cDNA libraries. As of 23 October 1998, 352,040 sequences had been generated, annotated and deposited in dbEST, where they comprised 93% of the total ESTs available for mouse. EST data are versatile and have been applied to gene identification, comparative sequence analysis, comparative gene mapping and candidate disease gene identification, genome sequence annotation, microarray development and the development of gene-based map resources.

Transcutaneous oxygen monitoring in congenital diaphragmatic abnormalities

The article considers the use of transcutaneous (Tc) partial pressure of oxygen (PO2) monitoring as an alternative form of continuous monitoring of respiratory function in paediatric critical care. The principles of TcPO2 monitoring are discussed. The relationship between TcPO2, arterial blood gases and oxygen saturation is highlighted by examining trends in TcPO2 derived in three neonates with congenital diaphragmatic abnormality. The effect of critical incidents upon TcPO2 is also explored. TcPO2 is unlikely to enhance the assessment of ventilation provided by pulse oximetry and blood gas analysis.

Urinary problems after formation of a Mitrofanoff stoma

1. Bladder irrigation reduces occlusion of drains with clots and debris, thus protecting anastomoses. 2. Leakage from anastomoses is an acknowledged problem postoperatively but resolves spontaneously in the majority of cases. 3. To establish urinary continence a good fluid intake is essential, bladder capacity must be developed, intermittent catheterisation taught and excessive mucus production eliminated. 4. The risk of urinary tract infections can be minimised by drinking cranberry juice, prophylactic antibiotic therapy and a good intermittent catheterisation technique. A degree of bacteria is inevitable and not always significant.

Complications of nailing in closed tibial fractures

Reamed intramedullary nailing was used to treat 102 closed tibial shaft fractures. Although a high rate of union was achieved (98%), we noted a higher incidence of complications than previously reported. Thirty-five (37%) patients exhibited one or more components of malunion. In 17 (18%) patients, further operative procedures were required to achieve union or to correct malalignment. New, postoperative peroneal nerve lesions were found in 19 (19%) patients, of which four (4%) failed to resolve. Acute compartment syndrome, requiring fasciotomy, developed in seven (7%) cases after surgery. Two patients developed an atrophic nonunion. In spite of these complications, the overall results were good and we continue to recommend this method of treatment for the displaced, unstable tibial shaft fracture.

Childhood sexual abuse

Childhood sexual abuse is a common problem. Patients with subacute and nonacute injuries may be treated in the physician's office. Patients with acute injuries are usually best managed in an emergency department where forensic testing can be performed efficiently. Physicians need to know how to appropriately interview children with signs of acute and subacute trauma. The physical examination should be thorough, nontraumatic and well documented. Evidence of inflammation, infection, and acute or healed trauma should be sought. Attention should be paid to sexually transmitted diseases, pregnancy prevention and mental health needs. Coordination with child welfare services, mental health professionals and law enforcement officers is often indicated. Awareness of the various presentations of sexual abuse and familiarity with normal and abnormal genital findings are necessary for the initial evaluation of these children.

Experience with silastic gel sheeting in pediatric scarring

Silicone gel sheeting was applied to five hypertrophic scars on five pediatric outpatients at an acute care pediatric hospital. After silicone gel application, three of the five scars showed initial positive results including reduction in the scar size, reduction in the scar thickness, softening of the scar, a decrease in vascularity of the scar, and more uniform pigmentation. Many negative results including rash, skin breakdown, cessation of scar responsiveness, problems with the gel sheet application, and poor durability were documented. Preliminary results indicate that topical silicone gel application is not a viable treatment option for the control of hypertrophic scarring with a pediatric population.

Total quality management at Bethesda, Inc

This article describes 4 years of TQM implementation at Bethesda, Inc., a private not-for-profit diversified healthcare organization. Bethesda has used a comprehensive implementation strategy involving the use of process improvement teams, hoshin planning, daily management of critical processes, and quality function deployment. The article includes four process improvement case studies demonstrating the use of the seven quality control tools and a nine-step process improvement model. Factors contributing to processes as well as obstacles are described.

Total body composition by dual-photon (153Gd) absorptiometry

The lean-fat composition (%FATR) of soft tissue and the mineral mass of the skeleton were determined in vivo using dual-photon (153Gd) absorptiometry (dose under 2 mrem). A rectilinear raster scan was made over the entire body in 18 subjects (14 female, 4 male). Single-photon absorptiometry (125I) measured bone mineral content on the radius. Percentage fat (%FATD) was determined in the same subjects using body density (from underwater weighing with correction for residual lung volume). Lean body mass (LBM) was determined using both %FATR and %FATD. Percentage fat from absorptiometry and from underwater density were correlated (r = 0.87). The deviation of %FATD from %FATR was due to the amount of skeletal mineral as a percentage of the LBM (r = 0.90). Therefore, skeletal variability, even in normal subjects, where mineral ranges only from 4 to 8% of the LBM, essentially precludes use of body density as a composition indicator unless skeletal mass is measured. Anthropometry (fatfolds and weight) predicted %FATR and LBM at least as well as did underwater density. The predictive error of %FATR from fatfolds was 5% while the predictive error in predicting LBM from anthropometry was 2 to 3 kg (3%).

Relationship between Science and Technology

Do economic advances spring directly from fundamental scientific discoveries? The early history of the transistor suggests that the situation is not nearly so simple as this.