17 years' experience of surgical management of thoracic outlet syndrome at a district general hospital

INTRODUCTION

Thoracic outlet syndrome (TOS) is caused by compression of the neurovascular structures passing through the thoracic inlet. It is categorised into three subtypes: neurogenic TOS (NTOS), venous TOS (VTOS) and arterial TOS (ATOS). This study evaluates the outcomes of patients who underwent first rib resection (FRR) for TOS during a period of 17 years at a single district general hospital.

METHODS

Retrospective review of patient notes of individuals treated with FRR from August 2004 to August 2021.

RESULTS

A total of 62 FRRs were performed on 51 individual patients. Indications for FRR included 42 NTOS (68%), 6 VTOS (10%) and 14 ATOS (23%). Thirty-four patients (64%) were female and the mean age at time of surgery was 39 years (range 27 to 64 years). Eleven patients (21%) underwent bilateral FRR and seven cases of cervical ribs were observed. The mean time from initial symptoms to diagnosis was 18 months (range 2 to 60 months). Overall, outcomes after surgery were positive across all subtypes of TOS. Based on Derkash's classification, 52 patients (84%) reported excellent/good, 8 (13%) reported fair and 2 (3%) reported poor resolution of symptoms at 6 month follow-up. Complications included four (9%) pneumothorax, two (4%) wound infections, two (4%) haematoma, one (2%) haemothorax, three (5%) phrenic nerve complications and one (2%) brachial neuropraxia.

CONCLUSIONS

FRR for TOS can be performed safely and effectively in a district general hospital environment with excellent patient clinical outcomes.

Development of a Cell-based Neutralizing Antibody Assay for Zinpentraxin Alfa: Challenges and Mitigation Strategies

Therapeutic protein drugs can potentially induce immune responses in patients and result in the production of anti-drug antibodies (ADAs), including a subset of ADAs called neutralizing antibodies (NAbs) that might cause loss of efficacy by inhibiting clinical activities of the drug. Herein, we describe the unique challenges encountered during the development of a fit-for-purpose cell-based NAb assay for a new protein modality, zinpentraxin alfa, including our strategies for assay design to overcome various matrix interferences and improve assay drug tolerance. We demonstrated that a typical biotin-drug extraction with acid dissociation (BEAD) approach alone was not sufficient to eliminate matrix interferences in this assay. Instead, the combination of the BEAD and ZebaTM spin size exclusion plate (SEP) was required to achieve the desirable assay performance. We also demonstrated that appropriate acidic buffers were critical in sample pretreatment to improve assay drug tolerance, which not only dissociated the drug/NAb immune complex but also effectively and irreversibly denatured the free drug. The final assay performed well with confirmed assay robustness and suitability for the clinical applications.

Ethical implications of AI in robotic surgical training: A Delphi consensus statement

CONTEXT

As the role of AI in healthcare continues to expand there is increasing awareness of the potential pitfalls of AI and the need for guidance to avoid them.

OBJECTIVES

To provide ethical guidance on developing narrow AI applications for surgical training curricula. We define standardised approaches to developing AI driven applications in surgical training that address current recognised ethical implications of utilising AI on surgical data. We aim to describe an ethical approach based on the current evidence, understanding of AI and available technologies, by seeking consensus from an expert committee.

EVIDENCE ACQUISITION

The project was carried out in 3 phases: (1) A steering group was formed to review the literature and summarize current evidence. (2) A larger expert panel convened and discussed the ethical implications of AI application based on the current evidence. A survey was created, with input from panel members. (3) Thirdly, panel-based consensus findings were determined using an online Delphi process to formulate guidance. 30 experts in AI implementation and/or training including clinicians, academics and industry contributed. The Delphi process underwent 3 rounds. Additions to the second and third-round surveys were formulated based on the answers and comments from previous rounds. Consensus opinion was defined as ≥ 80% agreement.

EVIDENCE SYNTHESIS

There was 100% response from all 3 rounds. The resulting formulated guidance showed good internal consistency, with a Cronbach alpha of >0.8. There was 100% consensus that there is currently a lack of guidance on the utilisation of AI in the setting of robotic surgical training. Consensus was reached in multiple areas, including: 1. Data protection and privacy; 2. Reproducibility and transparency; 3. Predictive analytics; 4. Inherent biases; 5. Areas of training most likely to benefit from AI.

CONCLUSIONS

Using the Delphi methodology, we achieved international consensus among experts to develop and reach content validation for guidance on ethical implications of AI in surgical training. Providing an ethical foundation for launching narrow AI applications in surgical training. This guidance will require further validation.

PATIENT SUMMARY

As the role of AI in healthcare continues to expand there is increasing awareness of the potential pitfalls of AI and the need for guidance to avoid them.In this paper we provide guidance on ethical implications of AI in surgical training.

Mycobacterium tuberculosis bloodstream infection prevalence, diagnosis, and mortality risk in seriously ill adults with HIV: a systematic review and meta-analysis of individual patient data

BACKGROUND

The clinical and epidemiological significance of HIV-associated Mycobacterium tuberculosis bloodstream infection (BSI) is incompletely understood. We hypothesised that M tuberculosis BSI prevalence has been underestimated, that it independently predicts death, and that sputum Xpert MTB/RIF has suboptimal diagnostic yield for M tuberculosis BSI.

METHODS

We did a systematic review and individual patient data (IPD) meta-analysis of studies performing routine mycobacterial blood culture in a prospectively defined patient population of people with HIV aged 13 years or older. Studies were identified through searching PubMed and Scopus up to Nov 10, 2018, without language or date restrictions and through manual review of reference lists. Risk of bias in the included studies was assessed with an adapted QUADAS-2 framework. IPD were requested for all identified studies and subject to harmonised inclusion criteria: age 13 years or older, HIV positivity, available CD4 cell count, a valid mycobacterial blood culture result (excluding patients with missing data from lost or contaminated blood cultures), and meeting WHO definitions for suspected tuberculosis (presence of screening symptom). Predicted probabilities of M tuberculosis BSI from mixed-effects modelling were used to estimate prevalence. Estimates of diagnostic yield of sputum testing with Xpert (or culture if Xpert was unavailable) and of urine lipoarabinomannan (LAM) testing for M tuberculosis BSI were obtained by two-level random-effect meta-analysis. Estimates of mortality associated with M tuberculosis BSI were obtained by mixed-effect Cox proportional-hazard modelling and of effect of treatment delay on mortality by propensity-score analysis. This study is registered with PROSPERO, number 42016050022.

FINDINGS

We identified 23 datasets for inclusion (20 published and three unpublished at time of search) and obtained IPD from 20, representing 96·2% of eligible IPD. Risk of bias for the included studies was assessed to be generally low except for on the patient selection domain, which was moderate in most studies. 5751 patients met harmonised IPD-level inclusion criteria. Technical factors such as number of blood cultures done, timing of blood cultures relative to blood sampling, and patient factors such as inpatient setting and CD4 cell count, explained significant heterogeneity between primary studies. The predicted probability of M tuberculosis BSI in hospital inpatients with HIV-associated tuberculosis, WHO danger signs, and a CD4 count of 76 cells per μL (the median for the cohort) was 45% (95% CI 38-52). The diagnostic yield of sputum in patients with M tuberculosis BSI was 77% (95% CI 63-87), increasing to 89% (80-94) when combined with urine LAM testing. Presence of M tuberculosis BSI compared with its absence in patients with HIV-associated tuberculosis increased risk of death before 30 days (adjusted hazard ratio 2·48, 95% CI 2·05-3·08) but not after 30 days (1·25, 0·84-2·49). In a propensity-score matched cohort of participants with HIV-associated tuberculosis (n=630), mortality increased in patients with M tuberculosis BSI who had a delay in anti-tuberculosis treatment of longer than 4 days compared with those who had no delay (odds ratio 3·15, 95% CI 1·16-8·84).

INTERPRETATION

In critically ill adults with HIV-tuberculosis, M tuberculosis BSI is a frequent manifestation of tuberculosis and predicts mortality within 30 days. Improved diagnostic yield in patients with M tuberculosis BSI could be achieved through combined use of sputum Xpert and urine LAM. Anti-tuberculosis treatment delay might increase the risk of mortality in these patients.

FUNDING

This study was supported by Wellcome fellowships 109105Z/15/A and 105165/Z/14/A.

Impurities in Oligonucleotide Drug Substances and Drug Products

This white paper, which is the 10th in a series intended to address issues associated with the development of therapeutic oligonucleotides, examines the subject of product-related impurities. The authors consider chemistry and safety aspects and advance arguments in favor of platform approaches to impurity identification and qualification. Reporting, identification, and qualification thresholds suitable for product-related impurities of therapeutic oligonucleotides are proposed.

Effect of an Early Resuscitation Protocol on In-hospital Mortality Among Adults With Sepsis and Hypotension: A Randomized Clinical Trial

IMPORTANCE

The effect of an early resuscitation protocol on sepsis outcomes in developing countries remains unknown.

OBJECTIVE

To determine whether an early resuscitation protocol with administration of intravenous fluids, vasopressors, and blood transfusion decreases mortality among Zambian adults with sepsis and hypotension compared with usual care.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial of 212 adults with sepsis (suspected infection plus ≥2 systemic inflammatory response syndrome criteria) and hypotension (systolic blood pressure ≤90 mm Hg or mean arterial pressure ≤65 mm Hg) presenting to the emergency department at a 1500-bed referral hospital in Zambia between October 22, 2012, and November 11, 2013. Data collection concluded December 9, 2013.

INTERVENTIONS

Patients were randomized 1:1 to either (1) an early resuscitation protocol for sepsis (n = 107) that included intravenous fluid bolus administration with monitoring of jugular venous pressure, respiratory rate, and arterial oxygen saturation and treatment with vasopressors targeting mean arterial pressure (≥65 mm Hg) and blood transfusion (for patients with a hemoglobin level <7 g/dL) or (2) usual care (n = 105) in which treating clinicians determined hemodynamic management.

MAIN OUTCOMES AND MEASURES

The primary outcome was in-hospital mortality and the secondary outcomes included the volume of intravenous fluid received and receipt of vasopressors.

RESULTS

Among 212 patients randomized to receive either the sepsis protocol or usual care, 3 were ineligible and the remaining 209 completed the study and were included in the analysis (mean [SD] age, 36.7 [12.4] years; 117 men [56.0%]; 187 [89.5%] positive for the human immunodeficiency virus). The primary outcome of in-hospital mortality occurred in 51 of 106 patients (48.1%) in the sepsis protocol group compared with 34 of 103 patients (33.0%) in the usual care group (between-group difference, 15.1% [95% CI, 2.0%-28.3%]; relative risk, 1.46 [95% CI, 1.04-2.05]; P = .03). In the 6 hours after presentation to the emergency department, patients in the sepsis protocol group received a median of 3.5 L (interquartile range, 2.7-4.0 L) of intravenous fluid compared with 2.0 L (interquartile range, 1.0-2.5 L) in the usual care group (mean difference, 1.2 L [95% CI, 1.0-1.5 L]; P < .001). Fifteen patients (14.2%) in the sepsis protocol group and 2 patients (1.9%) in the usual care group received vasopressors (between-group difference, 12.3% [95% CI, 5.1%-19.4%]; P < .001).

CONCLUSIONS AND RELEVANCE

Among adults with sepsis and hypotension, most of whom were positive for HIV, in a resource-limited setting, a protocol for early resuscitation with administration of intravenous fluids and vasopressors increased in-hospital mortality compared with usual care. Further studies are needed to understand the effects of administration of intravenous fluid boluses and vasopressors in patients with sepsis across different low- and middle-income clinical settings and patient populations.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01663701.

Nonacademic Attributes Predict Medical and Nursing Student Intentions to Emigrate or to Work Rurally: An Eight-Country Survey in Asia and Africa

AbstractWe sought to identify independent, nonacademic predictors of medical and nursing student intent to migrate abroad or from rural to urban areas after graduation in low- and middle-income countries (LMIC). This was a cross-sectional survey of 3,199 first- and final-year medical and nursing students at 16 training institutions in eight LMIC. Questionnaires assessed demographics, career intentions, and preferences regarding selected career, location, and work-related attributes. Using principal component analysis, student preferences were reduced into four discrete categories of priorities: 1) work environment resources, 2) location livability, 3) altruistic job values, and 4) individualistic job values. Students' preferences were scored in each category. Using students' characteristics and priority scores, multivariable proportional odds models were used to derive independent predictors of intentions to emigrate for work outside the country, or to work in a rural area in their native country. Students prioritizing individualistic values more often planned international careers (adjusted odds ratio [aOR] = 1.44, 95% confidence interval [CI] = 1.16-1.78), whereas those prioritizing altruistic values preferred rural careers (aOR = 1.82, 95% CI = 1.50-2.21). Trainees prioritizing high-resource environments preferentially planned careers abroad (aOR = 1.38, 95% CI = 1.12-1.69) and were unlikely to seek rural work (aOR = 0.60, 95% CI = 0.49-0.73). Independent of their priorities, students with prolonged prior rural residence were unlikely to plan emigration (aOR = 0.67, 95% CI = 0.50-0.90) and were more likely to plan a rural career (aOR = 1.53, 95% CI = 1.16-2.03). We conclude that use of nonacademic attributes in medical and nursing admissions processes would likely increase retention in high-need rural areas and reduce emigration "brain drain" in LMIC.

Derivation and validation of a universal vital assessment (UVA) score: a tool for predicting mortality in adult hospitalised patients in sub-Saharan Africa

Background

Critical illness is a leading cause of morbidity and mortality in sub-Saharan Africa (SSA). Identifying patients with the highest risk of death could help with resource allocation and clinical decision making. Accordingly, we derived and validated a universal vital assessment (UVA) score for use in SSA.

Methods

We pooled data from hospital-based cohort studies conducted in six countries in SSA spanning the years 2009–2015. We derived and internally validated a UVA score using decision trees and linear regression and compared its performance with the modified early warning score (MEWS) and the quick sepsis-related organ failure assessment (qSOFA) score.

Results

Of 5573 patients included in the analysis, 2829 (50.8%) were female, the median (IQR) age was 36 (27–49) years, 2122 (38.1%) were HIV-infected and 996 (17.3%) died in-hospital. The UVA score included points for temperature, heart and respiratory rates, systolic blood pressure, oxygen saturation, Glasgow Coma Scale score and HIV serostatus, and had an area under the receiver operating characteristic curve (AUC) of 0.77 (95% CI 0.75 to 0.79), which outperformed MEWS (AUC 0.70 (95% CI 0.67 to 0.71)) and qSOFA (AUC 0.69 (95% CI 0.67 to 0.72)).

Conclusion

We identified predictors of in-hospital mortality irrespective of the underlying condition(s) in a large population of hospitalised patients in SSA and derived and internally validated a UVA score to assist clinicians in risk-stratifying patients for in-hospital mortality. The UVA score could help improve patient triage in resource-limited environments and serve as a standard for mortality risk in future studies.

High prevalence of Mycobacterium tuberculosis bacteraemia among a cohort of HIV-infected patients with severe sepsis in Lusaka, Zambia

Tuberculosis is recognised as one of the leading causes of severe sepsis among HIV-infected patients. Most patients with Mycobacterium tuberculosis bacteraemia have advanced HIV disease with CD4 counts less than 100 cells/μl and its presentation is non-specific in most instances. This was a cross-sectional study which was done by analyzing data from 201 adult HIV-infected patients who met the inclusion criteria for severe sepsis. The prevalence of Mycobacterium tuberculosis bactraemia in the study population was 34.8%. Severe sepsis caused by other etiologies was observed in 33 (16.4%) of the participants. Concomitant infection of Mycobacterium tuberculosis bactraemia with other organisms is not uncommon in patients with severe sepsis. This cohort of HIV-infected patients had severe immunosuppression with a median CD4 count of 51 (20-136) cells/μl with moderate anaemia, mean haemoglobin 8.0 (3.0) g/dl, and were generally underweight with a mean mid upper arm circumference (MUAC) of 21.0 (3.4) cm. Mycobacterium tuberculosis bacteraemia is very common in HIV-infected patients with advanced HIV disease who present with severe sepsis. Mycobacterium tuberculosis bacteraemia co-infection with aerobic organisms is not uncommon. Factors that were independently associated with Mycobacterium tuberculosis bacteraemia in our study population were MUAC and sodium level.

How we implemented an analytical support clinic to strengthen student research capacity in Zambia

BACKGROUND

Research outputs in sub-Saharan Africa may be limited by a scarcity of clinical research expertise. In Zambia, clinical and biomedical postgraduate students are often delayed in graduation due to challenges in completing their research dissertations. We sought to strengthen institutional research capacity by supporting student and faculty researchers through weekly epidemiology and biostatistics clinics.

METHODS

We instituted a weekly Analytical Support Clinic at the University of Zambia, School of Medicine. A combination of biostatisticians, clinical researchers and epidemiologists meet weekly with clients to address questions of proposal development, data management and analysis. Clinic sign-in sheets were reviewed.

RESULTS

109 students and faculty members accounted for 197 visits to the Clinic. Nearly all clients (107/109, 98.2%) were undergraduate or postgraduate students. Reasons for attending the Clinic were primarily for proposal development (46.7%) and data management/analysis (42.1%). The most common specific reasons for seeking help were data analysis and interpretation (36.5%), development of study design and research questions (26.9%) and sample size calculation (21.8%).

CONCLUSIONS

The Analytical Support Clinic is an important vehicle for strengthening postgraduate research through one-on-one and small group demand-driven interactions. The clinic approach supplements mentorship from departmental supervisors, providing specific expertise and contextual teaching.

Medical and nursing students' intentions to work abroad or in rural areas: a cross-sectional survey in Asia and Africa

OBJECTIVE

To assess medical and nursing students' intentions to migrate abroad or practice in rural areas.

METHODS

We surveyed 3199 first- and final-year medical and nursing students at 16 premier government institutions in Bangladesh, Ethiopia, India, Kenya, Malawi, Nepal, the United Republic of Tanzania and Zambia. The survey contained questions to identify factors that could predict students' intentions to migrate. Primary outcomes were the likelihoods of migrating to work abroad or working in rural areas in the country of training within five years post-training. We assessed predictors of migration intentions using multivariable proportional odds models.

FINDINGS

Among respondents, 28% (870/3156) expected to migrate abroad, while only 18% (575/3158) anticipated a rural career. More nursing than medical students desired professions abroad (odds ratio, OR: 1.76; 95% confidence interval, CI: 1.25-2.48). Career desires before matriculation correlated with current intentions for international (OR: 4.49; 95% CI: 3.21-6.29) and rural (OR: 4.84; 95% CI: 3.52-6.66) careers. Time spent in rural areas before matriculation predicted the preference for a rural career (20 versus 0 years: OR: 1.53, 95% CI: 1.19-1.98) and against work abroad (20 versus 0 years: OR: 0.69, 95% CI: 0.50-0.96).

CONCLUSION

A significant proportion of students surveyed still intend to work abroad or in cities after training. These intentions could be identified even before matriculation. Admissions standards that account for years spent in rural areas could promote greater graduate retention in the country of training and in rural areas.

Strengthening faculty recruitment for health professions training in basic sciences in Zambia

Zambia is facing a crisis in its human resources for health, with deficits in the number and skill mix of health workers. The University of Zambia School of Medicine (UNZA SOM) was the only medical school in the country for decades, but recently it was joined by three new medical schools--two private and one public. In addition to expanding medical education, the government has also approved several allied health programs, including pharmacy, physiotherapy, biomedical sciences, and environmental health. This expansion has been constrained by insufficient numbers of faculty. Through a grant from the Medical Education Partnership Initiative (MEPI), UNZA SOM has been investing in ways to address faculty recruitment, training, and retention. The MEPI-funded strategy involves directly sponsoring a cohort of faculty at UNZA SOM during the five-year grant, as well as establishing more than a dozen new master's programs, with the goal that all sponsored faculty are locally trained and retained. Because the issue of limited basic science faculty plagues medical schools throughout Sub-Saharan Africa, this strategy of using seed funding to build sustainable local capacity to recruit, train, and retain faculty could be a model for the region.

Medical students' clerkship experiences and self-perceived competence in clinical skills

INTRODUCTION

In a traditional curriculum, medical students are expected to acquire clinical competence through the apprenticeship model using the Halstedian "see one, do one, and teach one, approach". The University of Zambia School of Medicine used a traditional curriculum model from 1966 until 2011 when a competence-based curriculum was implemented.

OBJECTIVE

To explore medical students' clerkships experiences and self-perceived competence in clinical skills.

METHODS

A cross-sectional survey was conducted on 5th, 6th, and 7th year medical students of the University of Zambia, School of Medicine two months prior to final examinations. Students were asked to rate their clerkship experiences with respect to specific skills on a scale of 1 to 4 and their level of self-perceived competence on a scale of 1 to 3. Skills evaluated were in four main domains: history taking and communication, physical examination, procedural, and professionalism, team work and medical decision making. Using Statistical Package for Social Scientist (SPSS), correlations were performed between experiences and self-perceived competence on specific skills, within domains and overall.

RESULTS

Out of 197 clinical students 138 (70%) participated in the survey. The results showed significant increase in the proportion of students performing different skills and reporting feeling very competent with each additional clinical year. Overall correlations between experience and self-perceived competence were moderate (0.55). On individual skills, the highest correlation between experience and self-perceived competence were observed on mainly medical and surgical related procedural skills with the highest at 0.82 for nasal gastric tube insertion and 0.76 for endotracheal intubation.

CONCLUSION

Despite the general improvement in skills experiences and self-perceived competence, some deficiencies were noted as significant numbers of final year students had never attempted common important procedures especially those performed in emergency situations. Deficiencies in certain skills may call for incorporation of teaching/learning methods that broaden students' exposure to such skills.

Objective predictors of delayed-onset post-traumatic stress disorder occurring after military discharge

BACKGROUND

Post-traumatic stress disorder (PTSD) that develops after military personnel have been discharged may lead to severe impairment. We investigated whether personnel who develop PTSD after discharge can be identified by independent evidence of internalizing signs such as depression or of externalizing signs such as disciplinary offences while still serving.

METHOD

Veterans in receipt of a war pension who only developed PTSD post-discharge were compared with matched veterans who developed PTSD in service or never suffered from PTSD. Contemporaneous medical and personnel records were searched for objective evidence of internalizing and externalizing disorder.

RESULTS

Service personnel who developed PTSD post-discharge were indistinguishable from controls with no PTSD on their psychiatric presentation in service. Those with post-discharge PTSD had significantly more disciplinary offences, specifically absence without leave, disobedience, and dishonesty, than the no-PTSD group, and this excess of offences was present before any exposure to trauma.

CONCLUSIONS

This is the first study to find objective evidence independent of self-report for the claimed link between externalizing disorder and vulnerability to PTSD. Early signs of externalizing disorders may play an important role in helping to identify service personnel at risk of PTSD after military discharge.

Some hazards are more attractive than others: drivers of varying experience respond differently to different types of hazard

The ability to detect hazards in video clips of driving has been inconsistently linked to driving experience and skill. One potential reason for the lack of consistency is the failure to understand the structural differences between those hazards that discriminate between safe and unsafe drivers, and those that do not. The current study used a car simulator to test drivers of differing levels of experience on approach to a series of hazards that were categorized a priori according to their underlying structure. The results showed that learner drivers took longer to fixate hazards, although they were particularly likely to miss hazards that were obscured by the environment (such as a pedestrian emerging from behind a parked truck). While drivers with a moderate amount of experience were as fast as driving instructors to look at hazards, they spent the greatest amount of time looking at them. Only instructors' ability to detect hazards early in the approach translated into differences in driving speed for certain types of hazard. The results demonstrate that drivers of varying experience respond differently to different hazards, and lay the foundations for a hazard typology.

The Etiology And Outcome Of Adult Patients Presenting With Sepsis To The University Teaching Hospital, Lusaka, Zambia

BACKGROUND

Sepsis accounts for a significant burden of morbidity and mortality.In developed world, it is implicated as the second leading cause of non-cardiac death. Mortality from sepsis is on the increase with a mortality rate of 33-61%. In spite of the high burden of sepsis in sub Saharan Africa, data regarding the etiology and outcome of septic patients is limited. We conducted a prospective cohort study to describe the etiology, characteristic and outcome of patients presenting with sepsis to the University Teaching Hospital in Lusaka, Zambia.

METHODS

Patients who met the inclusion criteria were enrolled into the study and after a thorough examination, bloods were drawn for full blood count, urea and electrolytes, liver function tests and for culture. Samples for culture were collected under aseptic techniques and cultured for aerobic organisms. Biochemical and bacteriological methods were used to identify the isolates and antibiotic sensitivity patterns were determined using agar diffusion methods. Patients were then followed up until they either demised or were discharge.

RESULTS

A total of 161 patients were enrolled of which 110(68%) were HIV positive and 23(14%) had unknown HIV status. Bacteremia was found in 39 (24%) with the most isolated organism being staphylococcus aureus. Mortality in our cohort of septic patients was determinedat 40%. Identified predictors for in patient mortality were low admission Glasgow coma scale[OR 11.2(CI 3.5-36.4)], positive blood culture[OR 2.38(CI 1.14-4.95)] and HIV status, those with unknown HIV status were more likely to die than those who were HIV negative[OR 8.38(CI2.36-29.7)].

CONCLUSION

Most of the septic patients presenting to UTH had advanced immunosuppression (WHO stage 3 and 4) and had a high mortality rate. Staphylococcus aureus and streptococcus pneumoniae were the highest isolates. Identified predictors for in patient mortality could be used to try and improve outcome in septic patients at UTH.

Trauma, identity and mental health in UK military veterans

BACKGROUND

Military service can lead to profound changes in identity, both in servicemen's perception of themselves and in their relationship to the world, but the significance of these changes for psychopathology is unclear. We investigated whether the extent and valence of identity change was related to the degree of military trauma exposure or to post-traumatic stress disorder (PTSD) and suicide attempts. We further sought to describe the nature of such changes using qualitative analysis.

METHOD

A total of 153 veterans in receipt of a war pension for PTSD or physical disability were identified. Interviews established retrospectively DSM-IV diagnoses of PTSD and reports of suicidal ideation or behaviour since enlistment were examined.

RESULTS

Trauma exposure alone was unrelated to any measure of identity change. By contrast, PTSD was associated with a relationship to the world that had changed in a negative direction. It was also associated with a changed perception of self, which could be either positive or negative. After controlling for trauma exposure and PTSD, suicidal behaviours were associated with more negative perceptions of the world. These perceptions of the world included disillusionment about human nature and a more specific rejection of civilian life.

CONCLUSIONS

PTSD and suicidal behaviours in veterans seem not to be associated with significantly more negative views of the self but rather with more alienation from civilian life. This has serious consequences for engaging veterans in National Health Service (NHS) mental health services and for the provision of effective treatment.

Sociodemographic and behavioural characteristics of youth reporting HIV testing in three Caribbean countries

OBJECTIVES

Human Immunodeficiency Virus (HIV) testing is the gateway to treatment and care of HIV infection, however little is known about the HIV testing behaviours among Caribbean youth. The objective of this study was to determine the prevalence of HIV testing and to examine associations of HIV testing with sociodemographic characteristics and risk behaviours.

METHODS

Data were used from nationally representative surveys in three Caribbean countries: Guyana AIDS Indicator Survey 2005-2006; Haiti Demographic and Health Survey 2005-2006 and the Dominican Republic Demographic and Health Survey 2007. Youth 15-24 years who had ever heard of AIDS and ever had sex were selected, yielding samples of 875 in Guyana, 4199 in Haiti and 12 418 in the Dominican Republic. Bivariate tests were conducted to examine the associations between sociodemographic characteristics, risk behaviours and being tested for HIV.

RESULTS

The proportion of youth reporting HIV testing ranged from 17% in Haiti to 48% in the Dominican Republic. About 54% of youth in Haiti and less than one-third in the Dominican Republic initiated HIV testing. A greater proportion of females than males had ever tested in each country, ranging from 68% in Guyana to 82% in Haiti. Higher rates of HIV testing were observed among ever married youth and among youth with 2-4 lifetime sexual partners.

CONCLUSIONS

Males, rural and never married youth were less likely to be tested. Outreach at individual and community levels and public health messages targeting these youth should be implemented. There is also a need to mainstream gender into the design of programmes aimed at increasing uptake of HIV testing. Programmes which assist youth in accurately assessing their risk behaviours are also required to improve HIV testing.

Running over unknown rough terrain with a one-legged planar robot

The ability to traverse unknown, rough terrain is an advantage that legged locomoters have over their wheeled counterparts. However, due to the complexity of multi-legged systems, research in legged robotics has not yet been able to reproduce the agility found in the animal kingdom. In an effort to reduce the complexity of the problem, researchers have developed single-legged models to gain insight into the fundamental dynamics of legged running. Inspired by studies of animal locomotion, researchers have proposed numerous control strategies to achieve stable, one-legged running over unknown, rough terrain. One such control strategy incorporates energy variations into the system during the stance phase by changing the force-free leg length as a sinusoidal function of time. In this research, a one-legged planar robot capable of implementing this and other state-of-the-art control strategies was designed and built. Both simulated and experimental results were used to determine and compare the stability of the proposed controllers as the robot was subjected to unknown drop and raised step perturbations equal to 25% of the nominal leg length. This study illustrates the relative advantages of utilizing a minimal-sensing, active energy removal control scheme to stabilize running over rough terrain.

Commentary training improves responsiveness to hazards in a driving simulator

Can commentary driving produce safer drivers? Producing a verbal commentary of potential hazards during driving has long been considered by the police to improve hazard perception skills. In this study we investigated whether learner drivers would benefit from being trained to produce a commentary drive. All learners were initially assessed on a virtual route in a driving simulator that contained 9 hazards. One group of drivers was then trained in commentary driving, and their subsequent simulated driving behaviour was compared to a control group. The results showed that the trained group had fewer crashes, reduced their speed sooner on approach to hazards, and applied pressure to the brakes sooner than untrained drivers. Conversely the untrained drivers' behaviour on approach to hazards was symptomatic of being surprised at the appearance of the hazards. The benefit of training was found to be greater for certain types of hazard than others.

Prevalence and Factors Associated with Renal Dysfunction in HIV Positive and Negative Adults at the University Teaching Hospital, in Lusaka

BACKGROUND

Despite having the highest disease burden of HIV, Sub-Saharan Africa has limited data on HIV related kidney disease with most available data coming from the developed countries. Kidney disease is a recognised complication in HIV infected patients presenting with acute renal failure (ARF) or chronic kidney disease (CKD). This study investigated the prevalence and risk factors associated with renal dysfunction among hospitalised HIV infected patients at the University Teaching Hospital (UTH), Lusaka.

METHODOLOGY

We conducted a cross sectional study at the University Teaching Hospital Lusaka, in Zambia. Inclusion criteria were hospitalised patients aged 16years and above who consented to the study. Both HIV infected and uninfected patients were included in the study. After obtaining demographic information, study participants were screened for HIV upon their consenting for the test. A full clinical history and examination was done by study physician to determine factors associated with renal dysfunction.

RESULTS

Of the 300 recruited hospitalised patients in this cross sectional study, 142(47%) were HIV infected. We observed a high prevalence of renal dysfunction among hospitalised HIV infected patients compared to uninfected patients (42% vs. 27%, adjusted OR 1.99, 95% CI 1.20-3.28). They had a twofold increased likelihood of developing kidney dysfunction (OR 1.96,95 CI%; 1.21-3.17). The presence of vomiting was strongly associated with renal dysfunction in both HIV positive (AOR 7.77, 95% CI 2.46-24-53) and negative (AOR4.83, 95%CI 1.40-16.66) subgroups. WHO stage III was associated with renal dysfunction in HIV infected patients. Tenofovir use, (a first line antiretroviral drug in Zambia) and hypotension were not significant factors associated with kidney disease after adjusting for other clinical parameters.

CONCLUSION

Renal dysfunction is significantly higher among hospitalised HIV infected compared to uninfected, however tenofovir and hypotension were not associated with renal dysfunction.

Categorizing neonatal deaths: a cross-cultural study in the United States, Canada, and The Netherlands

OBJECTIVE

To clarify the process of end-of-life decision-making in culturally different neonatal intensive care units (NICUs).

STUDY DESIGN

Review of medical files of newborns >22 weeks gestation who died in the delivery room (DR) or the NICU during 12 months in 4 NICUs (Chicago, Milwaukee, Montreal, and Groningen). We categorized deaths using a 2-by-2 matrix and determined whether mechanical ventilation was withdrawn/withheld and whether the child was dying despite ventilation or physiologically stable but extubated for neurological prognosis.

RESULTS

Most unstable patients in all units died in their parents' arms after mechanical ventilation was withdrawn. In Milwaukee, Montreal, and Groningen, 4% to 12% of patients died while receiving cardiopulmonary resuscitation. This proportion was higher in Chicago (31%). Elective extubation for quality-of-life reasons never occurred in Chicago and occurred in 19% to 35% of deaths in the other units. The proportion of DR deaths in Milwaukee, Montreal, and Groningen was 16% to 22%. No DR deaths occurred in Chicago.

CONCLUSIONS

Death in the NICU occurred differently within and between countries. Distinctive end-of-life decisions can be categorized separately by using a model with uniform definitions of withholding/withdrawing mechanical ventilation correlated with the patient's physiological condition. Cross-cultural comparison of end-of-life practice is feasible and important when comparing NICU outcomes.

HIV/AIDS and Postnatal Depression at the University Teaching Hospital, Lusaka, Zambia

OBJECTIVE: To study the contribution of HIV/AIDS to the problem of postnatal depression among women receiving postnatal care at University Teaching Hospital (UTH), Lusaka, Zambia. BACKGROUND: Postnatal depression (PND), a major depressive episode during the puerperium, affects between 10% and 22% of adult women before the infant's first birthday. HIV seropositivity has been associated with increased risk of mental disease, but its influence on postnatal depression has not been fully explored. METHODS: This was a cross-sectional study, involving 229 mothers receiving postnatal care at UTH. The presence of postnatal depression and mean scores on the Edinburgh Postnatal Depression Scale (EPDS) were assessed, along with the patients' HIV status and other demographic and clinical characteristics. RESULTS: 146 of 229 patients (64%) had depressive symptoms as measured by an EPDS score ≥ 8. Sixty-four women (28%) had severe PND, defined as an EPDS score ≥ 13. There were 46 HIV positive women (20.1%). HIV status was not associated with PND (adjusted OR 1.22, 95% CI 0.50-2.96) or severe PND (adjusted OR 1.77, 95% CI 0.68-4.61). Mixed mode of infant feeding and parity of 4-5 were independently associated with PND. CONCLUSIONS: Depression is a real health problem among mothers attending postnatal care at UTH. HIV status was not independently associated with increased risk of postnatal depression. Keywords: postnatal depression, puerperium, Edinburgh Postnatal Depression Scale, prevalence of HIV/AIDS.

Performance of modified WHO presumptive criteria for diagnosis of HIV infection in children <18 months admitted to University Teaching Hospital in Lusaka

BACKGROUND: Making a diagnosis of HIV infection in children aged less than 18 months remains a challenge in low resource settings like Zambia due to the limited availability of gold standard testing with HIV DNA PCR. Clinicians in rural areas have to depend on clinical diagnosis to start HAART as they wait for the dry blood spot (DBS) for DNA PCR results sent from the urban centers. METHODS: This descriptive cross-sectional study was performed at the University Teaching Hospital, Lusaka, Zambia. 299 HIV-exposed children aged less than 18 months were enrolled following a consent procedure. Patients were evaluated for HIV infection based on the World Health Organization's presumptive diagnostic criteria (WHO-PDC), integrated management of childhood illnesses (IMCI) criteria, select physical exam abnormalities, and CD4% and findings were compared with HIV-DNA PCR results. RESULTS: Of the 299 exposed patients analyzed, 111(37%) were found to be HIV-positive by DNA PCR. The median CD4% in the infected children was 18%. WHO-PDC used on its own had 23% sensitivity (95% CI 17-32%) and 93% specificity (88-96%), respectively, whereas IMCI criterion had 10% sensitivity (6-17%) and 97% specificity (94-99%), respectively. Multivariate analysis was used to identify the most sensitive predictors when combined with the WHO-PDC and IMCI criterion. WHO-PDC with CD4% improved the sensitivity to 77% (68-83%) with a specificity of 83% (77-88%), positive predictive value (PPV) of 73% (64-80%) and negative predictive value (NPV) of 86% (80-90%). IMCI with CD4% improved sensitivity to 80% (71-87%) with a specificity of 88% (82-92%), PPV 78% (69-85%) and NPV 89% (84-93%). The addition of individual physical exam findings without CD4% improved the sensitivity of WHO-PDC only modestly. When the WHO-PDC, weight<3(rd) percentile, hepatomegaly, splenomegaly, lymphadenopathy and CD4% were combined, the sensitivity improved to 85% (77-90%), specificity 63% (56-70%), PPV 58% (50-65%) and NPV of 88% (81-92%). CONCLUSION: The WHO-PDC clinical algorithm can be improved when combined with a CD4% <25% in children less than 12 months of age and CD4% <20% in those between 12 and 18 months.

Traumatic diaphragmatic herniation presenting as a delayed tension faecopneumothorax

This article reports an unusual case of delayed presentation of a tension faecopneumothorax after traumatic injury to the diaphragm 5 years previously. Three important clinical lessons are highlighted: (a) for suspected tension pneumothorax, if a considerable quantity of serous fluid is drained in addition to air, a communication with the peritoneal cavity should be considered; (b) spontaneous tension pneumothorax is an extremely rare condition and other causes should be kept in mind; and (c) in the presence of a tension pneumothorax and diaphragmatic hernia, the contents of the visceral sac may be completely reduced and the hernia may be masked.

Minimally important difference in diffuse systemic sclerosis: results from the D-penicillamine study

OBJECTIVE

To estimate minimally important differences (MIDs) in scores for the modified Rodnan Skin Score (mRSS) and Health Assessment Questionnaire-Disability Index (HAQ-DI) in a clinical trial on diffuse systemic sclerosis (SSc).

PARTICIPANTS AND METHODS

134 people participated in a 2-year, double-blind, randomised clinical trial comparing efficacy of low-dose and high-dose D-penicillamine in diffuse SSc. At 6, 12, 18 and 24 months, the investigator was asked to rate the change in the patient's health since entering the study: markedly worsened, moderately worsened, slightly worsened, unchanged, slightly improved, moderately improved or markedly improved. Patients who were rated as slightly improved were defined as the minimally changed subgroup and compared with patients rated as moderately or markedly improved.

RESULTS

The MID estimates for the mRSS improvement ranged from 3.2 to 5.3 (0.40-0.66 effect size) and for the HAQ-DI from 0.10 to 0.14 (0.15-0.21 effect size). Patients who were rated to improve more than slightly were found to improve by 6.9-14.2 (0.86-1.77 effect size) on the mRSS and 0.21-0.55 (0.32-0.83 effect size) on the HAQ-DI score.

CONCLUSION

MID estimates are provided for improvement in the mRSS and HAQ-DI scores, which can help in interpreting clinical trials on patients with SSc and be used for sample size calculation for future clinical trials on diffuse SSc.

Association of pre- and postoperative plasma levels of transforming growth factor beta(1) and interleukin 6 and its soluble receptor with prostate cancer progression

PURPOSE

We have shown that preoperative plasma levels of transforming growth factor-beta(1) (TGF-beta(1)), interleukin 6 (IL)-6, and its receptor (IL-6sR) are associated with prostate cancer progression and metastasis. The objectives of this study were to confirm these findings and to examine the association of changes in plasma levels of these markers after surgery with disease progression in a large consecutive cohort of patients.

EXPERIMENTAL DESIGN

Plasma levels of TGF-beta(1), IL-6, and IL-6sR were measured pre- and postoperatively (6-8 weeks after surgery) in 302 consecutive patients who underwent radical prostatectomy for clinically localized disease.

RESULTS

Pre- and postoperative levels of TGF-beta(1) were significantly elevated in patients with extraprostatic extension, seminal vesicle involvement, and metastases to lymph nodes. In contrast, preoperative levels of IL-6 and IL-6sR, but not postoperative levels, were significantly associated with tumor volume, prostatectomy Gleason sum, and metastases to lymph nodes. In a postoperative model that included pre- and postoperative TGF-beta(1), IL-6, and IL-6sR and standard postoperative parameters, postoperative TGF-beta(1) and prostatectomy Gleason sum were significant predictors of overall and aggressive disease progression. Although, for all patients, plasma levels of all three markers declined significantly after prostate removal, for patients that experienced disease progression, only IL-6 and IL-6sR levels decreased significantly.

CONCLUSIONS

For patients undergoing radical prostatectomy, preoperative plasma levels of TGF-beta(1) and IL-6sR are associated with metastases to regional lymph nodes, presumed occult metastases at the time of primary treatment, and disease progression. After prostate removal, postoperative TGF-beta(1) level increases in value over preoperative levels for the prediction of disease progression.

The addition of interleukin-6 soluble receptor and transforming growth factor beta1 improves a preoperative nomogram for predicting biochemical progression in patients with clinically localized prostate cancer

PURPOSE

Several preoperative prostate cancer nomograms have been developed that predict risk of progression using pretreatment prostate-specific antigen (PSA) level, clinical stage, and biopsy Gleason grade. We describe the development and performance of a new nomogram. The nomogram adds new markers to the standard clinical predictors that reflect the biologic behavior of prostate cancer: pretreatment plasma levels of interleukin-6 soluble receptor (IL6SR) and transforming growth factor beta1 (TGF-beta1).

PATIENTS AND METHODS

Between November 7, 1994 and December 22, 1997, 714 patients with stage cT1c to cT3a prostate cancer and no prior therapy were treated with radical prostatectomy at the Methodist Hospital, Houston TX. Plasma levels of IL6SR and TGF-beta1 were measured in banked preoperative plasma. With these data, a nomogram was developed to predict the probability of PSA progression within 5 years of surgery. The nomogram was validated with bootstrapping to assess its discrimination and calibration performance.

RESULTS

In the multivariable Cox model, PSA (P =.004), IL6SR (P <.001), TGF-beta1 (P <.001), primary Gleason grade (P <.002), and secondary Gleason grade (P =.029) were associated with PSA progression, whereas clinical stage (P =.696) was not. The nomogram seemed to be well calibrated and had a bootstrap-corrected area under the receiver operating characteristic curve (ie, concordance index) of 0.83. For comparison, a nomogram that omitted IL6SR and TGF-beta1 achieved a concordance index of only 0.75.

CONCLUSION

We found that pretreatment plasma levels of IL6SR and TGF-beta1 improved the ability to predict biochemical progression by a prognostically substantial margin. A nomogram including the pretreatment levels of these molecular markers, along with standard clinical markers, has been developed and internally validated.

Association of plasma urokinase-type plasminogen activator and its receptor with clinical outcome in patients undergoing radical cystectomy for transitional cell carcinoma of the bladder

OBJECTIVES

The urokinase plasminogen activation (uPA) system plays an important role in tumor invasion and metastasis by mediating proteolysis, adhesion, and migration of tumor cells. We tested the hypothesis that preoperative plasma levels of uPA and its specific receptor, uPAR, would predict cancer stage and prognosis in patients with transitional cell carcinoma of the bladder.

METHODS

The study group consisted of 51 patients who underwent radical cystectomy for muscle-invasive cancer or Tis, Ta, or T1 transitional cell carcinoma refractory to intravesical therapy and 44 men without cancer. Preoperative plasma levels of uPA and uPAR were measured by enzyme-linked immunosorbent assay in patients with available samples (51 and 38, respectively) and correlated with the clinical and pathologic characteristics and clinical outcome.

RESULTS

Plasma uPA and uPAR levels were both greater in those with bladder cancer than in the healthy subjects (P <0.001). Plasma uPAR levels were greatest in patients with metastases to distant lymph nodes (P = 0.042). Preoperative uPA was independently associated with metastases to regional lymph nodes (P = 0.017), lymphovascular invasion (P = 0.019), disease progression (P = 0.030), and death from bladder cancer (P = 0.038). uPAR was not associated with bladder cancer outcome.

CONCLUSIONS

Plasma uPA and uPAR levels were greater in those with bladder cancer compared with healthy controls. For patients with bladder cancer, a greater preoperative plasma uPA level was an independent predictor of poor outcome after radical cystectomy.

Preoperative plasma levels of interleukin-6 and its soluble receptor predict disease recurrence and survival of patients with bladder cancer

PURPOSE

Elevated levels of interleukin-6 (IL-6) are associated with metastasis and poor prognosis in various malignancies. Since the IL-6 soluble receptor (IL-6sR) potentiates the systemic effects of IL-6, each may independently impact the disease process. We tested the hypothesis that preoperative plasma IL-6 and IL-6sR levels would predict cancer stage and prognosis in patients with transitional cell carcinoma of the bladder.

MATERIALS AND METHODS

The study group consisted of 51 patients who underwent radical cystectomy for transitional cell carcinoma and 44 men without cancer. Preoperative plasma levels of IL-6 and IL6sR were measured by enzyme-linked immunosorbent assay and correlated with pathological features and clinical outcome.

RESULTS

IL-6 levels were higher in patients with bladder cancer than in healthy controls (p <0.001). In bladder cancer cases elevated levels of IL-6 and IL-6sR were associated with adverse pathological features, including muscle invasion, lymphovascular invasion and lymph node metastases (p <0.05). High levels of IL-6sR were also associated with pathological tumor grade (p = 0.036). In separate multivariate models that included clinical stage and grade IL-6 and IL-6sR levels were independent predictors of lymphovascular invasion, metastases to lymph nodes, disease recurrence and disease specific survival (p <0.05). In a preoperative Cox proportional hazards model IL-6 (p = 0.050) and IL-6sR (p = 0.035) predicted disease specific survival.

CONCLUSIONS

We found that plasma IL-6 levels were higher in patients with bladder cancer than in healthy controls. Levels of IL-6 and IL-6sR were associated with cancer stage and metastases, and were strong independent predictors of disease recurrence and disease specific survival.