Integration of the RTS,S/AS01 malaria vaccine into the Essential Programme on Immunisation in western Kenya: a qualitative longitudinal study from the health system perspective

BACKGROUND

Malaria accounts for over half a million child deaths annually. WHO recommends RTS,S/AS01 to prevent malaria in children living in moderate-to-high malaria transmission regions. We conducted a qualitative longitudinal study to investigate the contextual and dynamic factors shaping vaccine delivery and uptake during a pilot introduction in western Kenya.

METHODS

The study was conducted between Oct 3, 2019, and Mar 24, 2022. We conducted participant and non-participant observations and in-depth interviews with health-care providers, health managers, and national policymakers at three timepoints using an iterative approach and observations of practices and processes of malaria vaccine delivery. Transcripts were coded by content analysis using the consolidated framework for implementation research, to which emerging themes were added deductively and categorised into challenges and opportunities.

FINDINGS

We conducted 112 in-depth interviews with 60 participants (25 health-care providers, 27 managers, and eight policy makers). Health-care providers highlighted limitations in RTS,S/AS01 integration into routine immunisation services due to the concurrent pilot evaluation and temporary adaptations for health reporting. Initial challenges related to the complexity of the four-dose schedule (up to 24-months); however, self-efficacy increased over time as the health-care providers gained experience in vaccine delivery. Low uptake of the fourth dose remained a challenge. Health managers cited insufficient trained immunisation staff and inadequate funding for supervision. Confidence in the vaccine increased among all participant groups owing to reductions in malaria frequency and severity.

INTERPRETATION

Integration of RTS,S/AS01 into immunisation services in western Kenya presented substantial operational challenges most of which were overcome in the first 2 years, providing important lessons for other countries. Programme expansion is feasible with intensive staff training and retention, enhanced supervision, and defaulter-tracing to ensure uptake of all doses.

FUNDING

PATH via World Health Organization; Gavi, the Vaccine Alliance; The Global Fund; and Unitaid.

RTS,S/AS01 malaria vaccine pilot implementation in western Kenya: a qualitative longitudinal study to understand immunisation barriers and optimise uptake

BACKGROUND

Malaria is a significant public health threat in sub-Saharan Africa, particularly among children. The RTS,S/AS01 malaria vaccine reduces the risk and severity of malaria in children. RTS,S/AS01 was piloted in three African countries, Ghana, Kenya and Malawi, to assess safety, feasibility and cost-effectiveness in real-world settings. A qualitative longitudinal study was conducted as part of the feasibility assessment. This analysis explores RTS,S/AS01 vaccination barriers and identifies potential motivators among caregivers in three sub-counties in western Kenya.

METHODS

A cohort of 63 caregivers with a malaria vaccine eligible child was interviewed at three time points over 24 months. A sub-set of 11 caregivers whose eligible children were either partially or non-vaccinated were selected for this sub-analysis. The 5A Taxonomy for root causes of under-vaccination was used to organise the inductively-coded data into categories (awareness, acceptance, access, affordability, and activation) and identify the factors influencing uptake across caregivers. A trajectory analysis was conducted to understand changes in factors over time within each caregiver experience. Caregiver narratives are used to illustrate how the factors influencing uptake were interrelated and changed over time.

RESULTS

Lack of awareness, previous negative experiences with routine childhood immunisations and the burden of getting to the health facility contributed to caregivers initially delaying uptake of the vaccine. Over time concerns about vaccine side effects diminished and anticipated vaccination benefits strongly motivated caregivers to vaccinate their children. Persistent health system barriers (e.g., healthcare provider strikes, vaccine stockouts, negative provider attitudes) meant some children missed the first-dose eligibility window by aging-out.

CONCLUSIONS

Caregivers in this study believed the RTS,S/AS01 to be effective and were motivated to have their children vaccinated. Despite these positive perceptions of the malaria vaccine, uptake was substantially hindered by persistent health system constraints. Negative provider attitudes emerged as a powerful deterrent to attending immunisation services and hampered uptake of the vaccine. Strategies that focus on improving interpersonal communication skills among healthcare providers are needed.

Perceptions of quality and the integrated delivery of family planning with childhood immunisation services in Kenya and Uganda

The integration of family planning (FP) with childhood immunisations is considered a promising approach to addressing postpartum women’s unmet need for FP in resource limited settings. This study set out to examine client and health provider perceptions of the quality of FP services that were integrated with childhood immunisations in Kenya and Uganda. Semi-structured interviews with clients (n = 30) and health providers (n = 27) were conducted in 16 rural health facilities. Interviews centred on the respondents’ experiences receiving/delivering FP services, their interactions with providers/clients, and their views on the quality of FP services. Client and provider perceptions of quality were compared through a thematic analysis of interview transcripts, and findings were synthesised using Jain and Hardee’s revised FP Quality of Care Framework. Using audit data, health facility characteristics and resources were also summarised through descriptive statistics to contextualise the qualitative findings. The dignity and respect experienced by clients was central to the respondents’ perceptions of quality. These two dimensions were not conceptualised as distinct facets of quality, but were instead perceived to be a product of the 1) access to needed services, 2) choice of contraceptives, 3) interpersonal communication, 4) information, and 5) confidentiality afforded to clients. Additionally, clients and providers alike believed that the integration of FP services with childhood immunisations had a positive effect on clients’ access to needed services and on the confidentiality they experienced in a context where modern contraceptive use was stigmatised and where a lack of support from some husbands impeded access to FP services. Understanding clients’ and providers’ conceptualisation of quality is critical to the design of high quality and client-centred integrated FP services.

"It was my own decision": the transformational shift that influences a woman's decision to use contraceptives covertly

BACKGROUND

Family planning (FP) is an important element of sexual and reproductive health and rights, but socio-cultural barriers and unbalanced gender relations often limit women's decision-making about contraceptive use. Covert contraceptive use (CCU) exemplifies the limits on women's decision-making and represents a way in which some women overcome constraints to achieve their reproductive goals. This study explores the decision-making process through which women choose to use contraceptives covertly.

METHODS

A qualitative synthesis was conducted using data from women, health providers, community members, health administrators, and intervention implementers (n = 400) to explore the decision-making process through which women choose to use contraceptives covertly. Interviews and focus group discussions were conducted at two time points as part of an evaluation of interventions integrating FP and childhood immunisation services at sites in Benin, Kenya, Malawi and Uganda. The sexual and reproductive health empowerment framework by Karp et al. (2020) was adapted and used to guide the analysis.

RESULTS

Women recognised that although they suffered the negative consequences of frequent pregnancies and of raising large families, they lacked overt decision-making power over their fertility. Women were confident to engage in CCU because they believed their husbands did not understand these consequences nor acknowledged their suffering, which justified not informing them. CCU was a difficult choice however, women felt comfortable voicing their reproductive preferences in settings where health providers were supportive.

CONCLUSIONS

Women chose to use contraceptives covertly when they questioned the unfairness of their situation and recognised their own power to act in accordance with their reproductive preferences. This represented an important shift in a woman's perception of who is entitled to make decisions about contraceptive use. Importantly, health providers can play a key role in supporting women's autonomous decision making about contraceptive use and should be careful not to undermine women's confidence.

Acceptability of family planning in a changing context in Uganda: a realist evaluation at two time points

OBJECTIVES

This study sought to understand, during an intervention which integrated family planning (FP) and immunisation, (1) if and how prevailing contextual factors influenced acceptability and use of modern contraceptive methods (MCMs) in a pastoral community in Uganda, (2) what mechanisms were triggered by these contextual factors (3) if these contextual factors changed between two time points 2 years apart and (4) the impact of contextual changes on mechanisms triggered and acceptability and use outcomes.

DESIGN

Qualitative realist evaluation over two time points.

SETTING

Government health facilities in Moroto District, Karamoja, Uganda.

PARTICIPANTS

69 participants involved in the delivery and uptake of integrated FP and childhood immunisation services.

INTERVENTION

Integrated delivery of FP and childhood immunisation services offered to women accessing immunisation services in health facilities between January 2016 and December 2019.

RESULTS

Four key themes were identified that encompassed context and mechanisms influencing acceptability of MCMs across both time points of the evaluation. These were: (1) fear of side effects of MCMs; (2) preference for natural FP methods; (3) pastoral lifestyles in the community and (4) food insecurity. The context of these themes changed over time leading to the triggering of mechanisms with an overall increase in acceptability of MCMs over time. Key mechanisms of acceptability triggered included: affective attitude, intervention coherence, self-efficacy, perceived effectiveness and opportunity cost, leading to the development of three context-acceptability theories.

CONCLUSIONS

In this study, social and cultural norms played a strong role in influencing acceptability of the intervention. The context combined with intervention components were found to trigger several mechanisms that mapped to constructs of diffusion of innovations and acted as catalysts for mechanisms of acceptability. The context in which the intervention was implemented changed leading to the triggering of mechanisms and an increase in the perceived value and acceptability of MCM use.

Healthcare provider and pregnant women's perspectives on the implementation of intermittent screening and treatment with dihydroartemisinin-piperaquine for malaria in pregnancy in western Kenya: a qualitative study

Background

In malaria endemic regions in Kenya, pregnant women are offered long-lasting insecticidal nets and intermittent preventive treatment (IPTp) with sulfadoxine–pyrimethamine (SP) at antenatal care (ANC) to prevent the adverse effects of malaria. Fears of growing SP resistance have heightened the search for alternative strategies. The implementation feasibility of intermittent screening and treatment (ISTp) with dihydroartemisinin–piperaquine (DP) in routine ANC settings was evaluated using qualitative and quantitative methods, including the exploration of healthcare provider and pregnant women’s perceptions.

Methods

Qualitative methods included data from 13 focus group discussions (FGDs) with pregnant women and 43 in-depth interviews with healthcare providers delivering ANC services. FGDs were conducted with women who had received either ISTp-DP or current policy (IPTp-SP). Thematic analysis was used to explore experiences among women and providers and findings were used to provide insights into results of the parallel quantitative study.

Results

Women were accepting of testing with rapid diagnostic tests (RDTs) and receiving treatment if malaria positive. Providers perceived DP to be an effective drug and well tolerated by women. Some providers indicated a preference for test and treat strategies to reduce unnecessary exposure to medication in pregnancy, others preferred a hybrid strategy combining screening at every ANC visit followed by IPTp-SP for women who tested negative, due to the perception that RDTs missed some infections and concerns about the growing resistance to SP. Testing with RDTs during ANC was appreciated as it was perceived to reduce wait times. The positive attitude of healthcare providers towards ISTp supports findings from the quantitative study that showed a high proportion (90%) of women were tested at ANC. There were concerns about affordability of DP and the availability of sufficient RDT stocks.

Conclusion

In ANC settings, healthcare providers and pregnant women found ISTp-DP to be an acceptable strategy for preventing malaria in pregnancy when compared with IPTp-SP. DP was considered an effective anti-malarial and a suitable alternative to IPTp-SP in the context of SP resistance. Despite providers’ lack of confidence in RDT results at current levels of sensitivity and specificity, the quantitative findings show their willingness to test women routinely at ANC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-03826-8.

Adoption of evidence-based global policies at the national level: intermittent preventive treatment for malaria in pregnancy and first trimester treatment in Kenya, Malawi, Mali and The Gambia

In 2012, the World Health Organization (WHO) updated its policy on intermittent preventive treatment in pregnancy with sulphadoxine-pyrimethamine (IPTp-SP). A global recommendation to revise the WHO policy on the treatment of malaria in the first trimester is under review. We conducted a retrospective study of the national policy adoption process for revised IPTp-SP dosing in four sub-Saharan African countries. Alongside this retrospective study, we conducted a prospective policy adoption study of treatment of first trimester malaria with artemisinin combination therapies (ACTs). A document review informed development and interpretation of stakeholder interviews. An analytical framework was used to analyse data exploring stakeholder perceptions of the policies from 47 in-depth interviews with a purposively selected range of national level stakeholders. National policy adoption processes were categorized into four stages: (1) identify policy need; (2) review the evidence; (3) consult stakeholders and (4) endorse and draft policy. Actors at each stage were identified with the roles of evidence generation; technical advice; consultative and statutory endorsement. Adoption of the revised IPTp-SP policy was perceived to be based on strong evidence, support from WHO, consensus from stakeholders; and followed these stages. Poor tolerability of quinine was highlighted as a strong reason for a potential change in treatment policy. However, the evidence on safety of ACTs in the first trimester was considered weak. For some, trust in WHO was such that the anticipated announcement on the change in policy would allay these fears. For others, local evidence would first need to be generated to support a change in treatment policy. A national policy change from quinine to ACTs for the treatment of first trimester malaria will be less straightforward than experienced with increasing the IPTp dosing regimen despite following the same policy processes. Strong leadership will be needed for consultation and consensus building at national level.

"As a woman who watches how my family is… I take the difficult decisions": a qualitative study on integrated family planning and childhood immunisation services in five African countries

Background

Family planning (FP) has the potential to improve maternal and child health outcomes and to reduce poverty in sub-Saharan Africa. However, substantial unmet need for modern contraceptive methods (MCMs) persists in this region. Current literature highlights multi-level barriers, including socio-cultural norms that discourage the use of MCMs. This paper explores women’s choices and decision-making around MCM use and examines whether integrating FP services with childhood immunisations influenced women’s perceptions of, and decision to use, an MCM.

Methods

94 semi-structured interviews and 21 focus group discussions with women, health providers, and community members (N = 253) were conducted in health facilities and outreach clinics where an intervention was delivering integrated FP and childhood immunisation services in Benin, Ethiopia, Kenya, Malawi and Uganda. Data were coded using Nvivo software and an analytical framework was developed to support interpretative and thematic analyses on women’s decision-making about MCM use.

Results

Most women shared the reproductive desire to space or limit births because of the perceived benefits of improved health and welfare for themselves and for their children, including the economic advantages. For some, choices about MCM use were restricted because of wider societal influences. Women’s decision to use MCMs was driven by their reproductive desires, but for some that was stymied by fears of side effects, community stigma, and disapproving husbands, which led to clandestine MCM use. Health providers acknowledged that women understood the benefits of using MCMs, but highlighted that the wider socio-cultural norms of their community often contributed to a reluctance to use them. Integration of FP and childhood immunisation services provided repeat opportunities for health providers to counter misinformation and it improved access to MCMs, including for women who needed to use them covertly.

Conclusions

Some women chose to use MCMs without the approval of their husbands, and/or despite cultural norms, because of the perceived health and economic benefits for themselves and for their families, and because they lived with the consequences of short birth intervals and large families. Integrated FP and childhood immunisation services expanded women’s choices about MCM use and created opportunities for women to make decisions autonomously.

Context-acceptability theories: example of family planning interventions in five African countries

BACKGROUND

Family planning (FP) can lengthen birth intervals and potentially reduce the risk of foetal death, low birthweight, prematurity, and being small for gestational age. Effective FP is most easily achieved through access to and acceptability of modern contraceptive methods (MCMs). This study aimed to identify mechanisms of acceptability and the contexts in which they are triggered and to generate theories to improve the selection and implementation of effective interventions by studying an intervention integrating FP with childhood immunisation services.

METHODS

Qualitative interpretative synthesis of findings from realist evaluations of FP interventions in five African countries was guided by an analytical framework. Empirical mechanisms of acceptability were identified from semi-structured interviews and focus group discussions with key stakeholders (N = 253). The context in which these mechanisms were triggered was also defined. Empirical mechanisms of acceptability were matched to constructs of a theoretical framework of acceptability. Context-acceptability theories (CATs) were developed, which summarised constructs of acceptability triggered for specific actors in specified contexts. Examples of interventions that may be used to trigger acceptability for these actors were described.

RESULTS

Seven CATs were developed for contexts with strong beliefs in religious values and with powerful religious leaders, a traditional desire for large families, stigmatisation of MCM use, male partners who are non-accepting of FP, and rumours or experiences of MCM side effects. Acceptability mechanisms included alignment with values and beliefs without requiring compromise, actors' certainty about their ability to avoid harm and make the intervention work, and understanding the intervention and how it works. Additionally, acceptability by one group of actors was found to alter the context, triggering acceptability mechanisms amongst others.

CONCLUSIONS

This study demonstrated the value of embedding realist approaches within implementation research. CATs are transferable theories that answer the question: given the context, what construct of acceptability does an intervention need to trigger, or more simply, what intervention do we need to apply here to achieve our outcomes? CATs facilitate transfer of interventions across geographies within defined contexts.

What mechanisms drive uptake of family planning when integrated with childhood immunisation in Ethiopia? A realist evaluation

Background

Maternal and child health are key priorities among the Sustainable Development Goals, which include a particular focus on reducing morbidity and mortality among women of reproductive age, newborns, and children under the age of five. Two components of maternal and child health are family planning (FP) and immunisation. Providing these services through an integrated delivery system could increase the uptake of vaccines and modern contraceptive methods (MCMs) particularly during the post-partum period.

Methods

A realist evaluation was conducted in two woredas in Ethiopia to determine the key mechanisms and their triggers that drive successful implementation and service uptake of an intervention of integrated delivery of immunisations and FP. The methodological approach included the development of an initial programme theory and the selection of relevant, published implementation related theoretical frameworks to aid organisation and cumulation of findings. Data from 23 semi-structured interviews were then analysed to determine key empirical mechanisms and drivers and to test the initial programme theory. These mechanisms were mapped against published theoretical frameworks and a revised programme theory comprised of context-mechanism-outcome configurations was developed. A critique of theoretical frameworks for abstracting empirical mechanisms was also conducted.

Results

Key contextual factors identified were: the use of trained Health Extension Workers (HEWs) to deliver FP services; a strong belief in values that challenged FP among religious leaders and community members; and a lack of support for FP from male partners based on religious values. Within these contexts, empirical mechanisms of acceptability, access, and adoption of innovations that drove decision making and intervention outcomes among health workers, religious leaders, and community members were identified to describe intervention implementation.

Conclusions

Linking context and intervention components to the mechanisms they triggered helped explain the intervention outcomes, and more broadly how and for whom the intervention worked. Linking empirical mechanisms to constructs of implementation related theoretical frameworks provided a level of abstraction through which findings could be cumulated across time, space, and conditions by theorising middle-range mechanisms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-10114-8.

How useful are malaria risk maps at the country level? Perceptions of decision-makers in Kenya, Malawi and the Democratic Republic of Congo

Background

Declining malaria prevalence and pressure on external funding have increased the need for efficiency in malaria control in sub-Saharan Africa (SSA). Modelled Plasmodium falciparum parasite rate (PfPR) maps are increasingly becoming available and provide information on the epidemiological situation of countries. However, how these maps are understood or used for national malaria planning is rarely explored. In this study, the practices and perceptions of national decision-makers on the utility of malaria risk maps, showing prevalence of parasitaemia or incidence of illness, was investigated.

Methods

A document review of recent National Malaria Strategic Plans was combined with 64 in-depth interviews with stakeholders in Kenya, Malawi and the Democratic Republic of Congo (DRC). The document review focused on the type of epidemiological maps included and their use in prioritising and targeting interventions. Interviews (14 Kenya, 17 Malawi, 27 DRC, 6 global level) explored drivers of stakeholder perceptions of the utility, value and limitations of malaria risk maps.

Results

Three different types of maps were used to show malaria epidemiological strata: malaria prevalence using a PfPR modelled map (Kenya); malaria incidence using routine health system data (Malawi); and malaria prevalence using data from the most recent Demographic and Health Survey (DRC). In Kenya the map was used to target preventative interventions, including long-lasting insecticide-treated nets (LLINs) and intermittent preventive treatment in pregnancy (IPTp), whilst in Malawi and DRC the maps were used to target in-door residual spraying (IRS) and LLINs distributions in schools. Maps were also used for operational planning, supply quantification, financial justification and advocacy. Findings from the interviews suggested that decision-makers lacked trust in the modelled PfPR maps when based on only a few empirical data points (Malawi and DRC).

Conclusions

Maps were generally used to identify areas with high prevalence in order to implement specific interventions. Despite the availability of national level modelled PfPR maps in all three countries, they were only used in one country. Perceived utility of malaria risk maps was associated with the epidemiological structure of the country and use was driven by perceived need, understanding (quality and relevance), ownership and trust in the data used to develop the maps.

Integrated delivery of family planning and childhood immunisation services in routine outreach clinics: findings from a realist evaluation in Malawi

BACKGROUND

Family planning (FP) needs among postpartum women in low- and middle-income countries remain largely unmet. Integrating FP with childhood immunisation services could partially reduce this unmet need by creating multiple opportunities for timely contact with FP services during the 12 months following childbirth.

METHODS

A realist evaluation of an intervention integrating FP and childhood immunisation services in routine outreach clinics in two rural districts of Malawi was conducted. A Context-Mechanism-Outcome (CMO) framework was used to describe the drivers of the intervention. A detailed programme theory was developed based on the analysis of semi-structured interviews and focus group discussions with 50 stakeholders.

RESULTS

A total of 9 core mechanisms were identified, which centred on constructs of access. Findings revealed that on the demand side, women were motivated to attend outreach clinics due to shorter travel distances; they felt confident they could access FP services and use contraceptive methods covertly if needed; and when supported by their husband, they were empowered to take up the use of contraceptive methods. On the supply side, providers were empowered through the training they received to provide integrated services; they were confident in their ability to provide essential services; and they were motivated by teamwork and by the recognition they received for their work. Additionally, some providers were found to be unwilling to walk long distances to reach remote clinics, which was seen to negatively affect the availability of services.

CONCLUSIONS

The delivery of integrated FP and childhood immunisation services in the context of routine outreach clinics in rural Malawi was seen to trigger mechanisms of accessibility and to improve the acceptability and availability of FP services. However, further research is needed to understand how the integration of these services in a routine outreach clinic setting may affect other dimensions of accessibility, including the approachability, appropriateness and affordability of services.

Integrated delivery of family planning and childhood immunisation services in routine outreach clinics: findings from a realist evaluation in Malawi

BACKGROUND

Family planning (FP) needs among postpartum women in low- and middle-income countries remain largely unmet. Integrating FP with childhood immunisation services could partially reduce this unmet need by creating multiple opportunities for timely contact with FP services during the 12 months following childbirth.

METHODS

A realist evaluation of an intervention integrating FP and childhood immunisation services in routine outreach clinics in two rural districts of Malawi was conducted. A Context-Mechanism-Outcome (CMO) framework was used to describe the drivers of the intervention. A detailed programme theory was developed based on the analysis of semi-structured interviews and focus group discussions with 50 stakeholders.

RESULTS

A total of 9 core mechanisms were identified, which centred on constructs of access. Findings revealed that on the demand side, women were motivated to attend outreach clinics due to shorter travel distances; they felt confident they could access FP services and use contraceptive methods covertly if needed; and when supported by their husband, they were empowered to take up the use of contraceptive methods. On the supply side, providers were empowered through the training they received to provide integrated services; they were confident in their ability to provide essential services; and they were motivated by teamwork and by the recognition they received for their work. Additionally, some providers were found to be unwilling to walk long distances to reach remote clinics, which was seen to negatively affect the availability of services.

CONCLUSIONS

The delivery of integrated FP and childhood immunisation services in the context of routine outreach clinics in rural Malawi was seen to trigger mechanisms of accessibility and to improve the acceptability and availability of FP services. However, further research is needed to understand how the integration of these services in a routine outreach clinic setting may affect other dimensions of accessibility, including the approachability, appropriateness and affordability of services.

Evaluation of Implementation of Intermittent Screening and Treatment for Control of Malaria in Pregnancy in Jharkhand, India

This study evaluated intermittent screening and treatment during pregnancy (ISTp) for malaria using rapid diagnostic tests (RDTs) at antenatal care (ANC) compared with passive case detection within the routine health system. The mixed-method evaluation included two cross-sectional household surveys (pre- and post-implementation of ISTp), in-depth interviews with health workers, and focus group discussions (FGDs) with pregnant women. Differences in proportions between surveys for a number of outcomes were tested; 553 and 534 current and recently pregnant women were surveyed (pre- and post-implementation, respectively). In-depth interviews were conducted with 29 health providers, and 13 FGDs were held with pregnant women. The proportion of pregnant women who received an RDT for malaria at ANC at least once during their pregnancy increased from pre- to post-implementation (19.2%; 95% CI: 14.9, 24.3 versus 42.5%; 95% CI: 36.6, 48.7; P < 0.0001), and the proportion of women who had more than one RDT also increased (16.5%; 95% CI: 13.1, 20.5 versus 27.7%; 95% CI: 23.0, 33.0; P = 0.0008). Post-implementation, however, only 8% of women who had completed their pregnancy received an RDT on three visits to ANC. Health workers were positive about ISTp mainly because of their perception that many pregnant women with malaria were asymptomatic. Health workers perceived pregnant women to have reservations about ISTp because of their dislike of frequent blood withdrawal, but pregnant women themselves were more positive. Intermittent screening and treatment during pregnancy was not sufficiently adopted by health workers to ensure the increased detection of malaria infections achievable with this strategy in this setting.

Intermittent screening and treatment or intermittent preventive treatment compared to current policy of single screening and treatment for the prevention of malaria in pregnancy in Eastern Indonesia: acceptability among health providers and pregnant women

BACKGROUND

The control of malaria in pregnancy in much of Asia relies on screening asymptomatic women for malaria infection, followed by passive case detection and prevention with insecticide-treated nets. In 2012, Indonesia introduced screening for malaria by microscopy or rapid diagnostic tests (RDTs) at pregnant women's first antenatal care (ANC) visit to detect and treat malaria infections regardless of the presence of symptoms. Acceptability among health providers and pregnant women of the current 'single screen and treat' (SSTp) strategy compared to two alternative strategies that were intermittent preventive treatment (IPTp) and intermittent screening and treatment (ISTp) was assessed in the context of a clinical trial in two malaria endemic provinces of Eastern Indonesia.

METHODS

Qualitative data were collected through in-depth interviews with 121 health providers working in provision of antenatal care, heads of health facilities and District Health Office staff. Trial staff were also interviewed. Focus group discussions were conducted with 16 groups of pregnant women (N = 106) to discuss their experiences of each intervention in the trial.

RESULTS

Health providers and pregnant women were receptive to screening for malaria at every ANC visit due to the increased opportunity to detect and treat asymptomatic infections. A primary concern for providers was the accuracy and availability of RDTs used for screening in the SSTp and ISTp arms, which they considered less accurate than microscopy. Providers had reservations about giving anti-malarials presumptively as IPTp, due to concerns of causing potential harm to mother and baby and as a possible driver of drug resistance. Pregnant women were accepting of all three interventions. Women in the IPTp arm were happy to take anti-malarials presumptively to protect themselves and their babies against malaria.

CONCLUSIONS

The findings indicate that, within a trial context, malaria screening of pregnant women at every ANC visit ISTp was an acceptable strategy among both health providers and pregnant women owing to an existing culture of screening and treatment. The adoption of IPTp however would require a considerable shift in health provider attitudes and a clear communication strategy. By contrast, pregnant women welcomed the opportunity to prevent malaria infections during pregnancy.

Evaluation of the national policy of single screening and treatment for the prevention of malaria in pregnancy in two districts in Eastern Indonesia: health provider perceptions

BACKGROUND

Malaria in pregnancy has devastating consequences for both the expectant mother and baby. Annually, 88.2 (70%) of the 125.2 million pregnancies in malaria endemic regions occur in the Asia-Pacific region. The control of malaria in pregnancy in most of Asia relies on passive case detection and prevention with long-lasting insecticide-treated nets. Indonesia was the first country in the region to introduce, in 2012, malaria screening at pregnant women's first antenatal care visit to reduce the burden of malaria in pregnancy. The study assessed health providers' acceptability and perceptions on the feasibility of implementing the single screening and treatment (SST) strategy in the context of the national programme in two endemic provinces of Indonesia.

METHODS

Qualitative data were collected through in-depth interviews with 86 health providers working in provision of antenatal care (midwives, doctors, laboratory staff, pharmacists, and heads of drug stores), heads of health facilities and District Health Office staff in West Sumba and Mimika districts in East Nusa Tenggara and Papua provinces, respectively.

RESULTS

Health providers of all cadres were accepting of SST as a preventive strategy, showing a strong preference for microscopy over rapid diagnostic tests (RDTs) as the method of screening. Implementation of the policy was inconsistent in both sites, with least extensive implementation reported in West Sumba compared to Mimika. SST was predominantly implemented at health centre level using microscopy, whereas implementation at community health posts was said to occur in less than half the selected health facilities. Lack of availability of RDTs was cited as the major factor that prevented provision of SST at health posts, however as village midwives cannot prescribe medicines women who test positive are referred to health centres for anti-malarials. Few midwives had received formal training on SST or related topics.

CONCLUSIONS

The study findings indicate that SST was an acceptable strategy among health providers, however implementation was inconsistent with variation across different localities within the same district, across levels of facility, and across different cadres within the same health facility. Implementation should be re-invigorated through reorientation and training of health providers, stable supplies of more sensitive RDTs, and improved data capture and reporting.

User and Provider Acceptability of Intermittent Screening and Treatment and Intermittent Preventive Treatment with Dihydroartemisinin-Piperaquine to Prevent Malaria in Pregnancy in Western Kenya

Background

The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) alongside long-lasting insecticide-treated nets (LLIN) and case management for reducing the risks associated with malaria in pregnancy in areas of moderate-to-high transmission in sub-Saharan Africa. Due to increasing Plasmodium falciparum resistance to SP, the search for alternative drugs or strategies to control malaria in pregnancy is a priority. We assessed the acceptability among pregnant women and health providers of intermittent screening and treatment (ISTp) and IPTp with dihydroartemisinin-piperaquine (DP) as alternative strategies in the context of an un-blinded clinical trial.

Methods

Qualitative data were collected through ten focus group discussions with women participating in a randomized controlled trial to evaluate ISTp or IPTp with DP (multi-day regimen) versus IPTp with SP (single dose) in western Kenya. Individual in-depth interviews were conducted with 26 health providers working in the trial facilities and trial staff.

Results

Women appreciated the advantages of being tested with a rapid diagnostic test (RDT) at every ANC visit (although a few women disliked finger pricks) and accepted that they would not receive any antimalarial when tested RDT-negative. There were differences in women’s experiences of the efficacy of antimalarials between the trial arms, with more women in the IPTp-SP arm reporting they had experienced malaria episodes. Side effects were experienced among women taking DP and SP. Although women and trial staff reported adherence to the full DP regimen within the trial, health providers were not confident that women would adhere to multi-day regimens in non-trial settings. Health providers recognized the advantages of ISTp in reducing unnecessary exposure to drugs, but lacked confidence in the reliability of RDTs compared to microscopy.

Conclusions

Our findings indicate that, within a trial context, ISTp-DP and IPTp-DP were generally acceptable among both users and providers and were regarded as potentially valuable alternatives to IPTp-SP. Several challenges were identified the most important of which was concerns with achieving adherence to DP in non-trial settings, requiring operational feasibility studies in routine health systems. Policy adoption of ISTp with RDTs would require a major shift in thinking among health providers due to lack of confidence in RDTs.

Prioritizing pregnant women for long-lasting insecticide treated nets through antenatal care clinics

Jenny Hill and colleagues discuss the importance of antenatal care services in providing pregnant women with a long-lasting insecticide treated net for the prevention of malaria in both the mother and infant. Please see later in the article for the Editors' Summary

Factors affecting the delivery, access, and use of interventions to prevent malaria in pregnancy in sub-Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Malaria in pregnancy has important consequences for mother and baby. Coverage with the World Health Organization-recommended prevention strategy for pregnant women in sub-Saharan Africa of intermittent preventive treatment in pregnancy (IPTp) and insecticide-treated nets (ITNs) is low. We conducted a systematic review to explore factors affecting delivery, access, and use of IPTp and ITNs among healthcare providers and women.

METHODS AND RESULTS

We searched the Malaria in Pregnancy Library and Global Health Database from 1 January 1990 to 23 April 2013, without language restriction. Data extraction was performed by two investigators independently, and data was appraised for quality and content. Data on barriers and facilitators, and the effect of interventions, were explored using content analysis and narrative synthesis. We conducted a meta-analysis of determinants of IPTp and ITN uptake using random effects models, and performed subgroup analysis to evaluate consistency across interventions and study populations, countries, and enrolment sites. We did not perform a meta-ethnography of qualitative data. Ninety-eight articles were included, of which 20 were intervention studies. Key barriers to the provision of IPTp and ITNs were unclear policy and guidance on IPTp; general healthcare system issues, such as stockouts and user fees; health facility issues stemming from poor organisation, leading to poor quality of care; poor healthcare provider performance, including confusion over the timing of each IPTp dose; and women's poor antenatal attendance, affecting IPTp uptake. Key determinants of IPTp coverage were education, knowledge about malaria/IPTp, socio-economic status, parity, and number and timing of antenatal clinic visits. Key determinants of ITN coverage were employment status, education, knowledge about malaria/ITNs, age, and marital status. Predictors showed regional variations.

CONCLUSIONS

Delivery of ITNs through antenatal clinics presents fewer problems than delivery of IPTp. Many obstacles to IPTp delivery are relatively simple barriers that could be resolved in the short term. Other barriers are more entrenched within the overall healthcare system or socio-economic/cultural contexts, and will require medium- to long-term strategies. Please see later in the article for the Editors' Summary.

Interactions of amylinergic and melanocortinergic systems in the control of food intake and body weight in rodents

AIMS

Amylinergic and melanocortinergic systems have each been implicated in energy balance regulation. We examined the interactive effects of both systems using gene knockout and pharmacological approaches.

METHODS

Acute food consumption was measured in overnight fasted male wild-type (WT) and melanocortin-4 receptor (MC-4R) deficient rats and in male and female WT and amylin knockout mice (AmyKO). Changes in food intake, body weight and composition in male WT and MC-4R deficient rats and in male diet-induced obese (DIO) rats. Pharmacological treatments included either rat amylin, murine leptin and/or the MC-4R agonist, Ac-R[CEH-dF-RWC]-amide.

RESULTS

Amylin (10 µg/kg, IP) decreased food intake in WT but not in MC-4R deficient rats (30 and 60 min post-injection). Ac-R[CEH-dF-RWC]-amide (100 µg/kg, IP) suppressed food intake similarly in male WT and AmyKO, but was ineffective in female AmyKO. Amylin (50 µg/kg/day for 28 days) and leptin (125 µg/kg/day) synergistically reduced food intake and body weight in WT and MC-4R deficient rats to a similar extent. Amylin (100 µg/kg) combined with Ac-R[CEH-dF-RWC]-amide (100 µg/kg, IP) decreased acute food intake over 3 h to a greater extent than either agent alone in fasted mice. In DIO rats, additive anorexigenic, weight- and fat-lowering effects were observed over 12 days with the combination of rat amylin (50 µg/kg/day) and Ac-R[CEH-dF-RWC]-amide (2.3 mg/kg, SC injected daily).

CONCLUSIONS

Although amylin's acute anorexigenic effects are somewhat blunted in MC-4R deficiency and those of MC-4R agonism in amylin deficiency, these effects are surmountable with pharmacological administration lending therapeutic potential to combined amylin/melanocortin agonism for obesity.

Spatially-resolved analysis of nanoparticle nucleation and growth in a microfluidic reactor

Microfluidic systems provide a unique platform for investigation of fundamental reaction processes, which is critical to understanding how to control nanostructure synthesis on a production scale. We have examined the synthesis of cysteine-capped CdS quantum dot nanocrystals (CdS-Cys) between two interdiffusing reagent streams in a continuous-flow microfluidic reactor. Using spatially resolved photoluminescence imaging and spectroscopy of the microreactor, we have acquired kinetic and mechanistic data on the CdS-Cys nanoparticle nucleation and growth, and observed a binary shift in the particle emission spectrum from a higher (2.9 eV) to lower (2.5 eV) energy emission peak within the first second of residence time. Several reactor models have been tested against the spatially and spectrally resolved signals, which suggest that homogeneous reaction and particle nucleation are diffusion-limited and occur only at the boundary between the two laminar streams, while a slower activation process occurs on a longer (seconds) time scale. The results provide direct insight into the rapid processes that occur during crystallization in microfluidic mixing channels, and demonstrate the potential of using controlled microfluidic environments with spatially resolved monitoring to conduct fundamental studies of nanocrystal nucleation and growth.

Effect of mechanical ventilation strategy on dissemination of intratracheally instilled Escherichia coli in dogs

OBJECTIVE

To test the effect of different mechanical ventilation strategies on dissemination of intratracheally instilled Escherichia coli in dogs and to determine the extent and distribution of lung damage.

DESIGN

Prospective, randomized study.

SETTING

Experimental animal laboratory.

SUBJECTS

Eighteen anesthetized and paralyzed dogs.

INTERVENTIONS

We studied the effect of three ventilatory strategies based on two variables: transpulmonary pressure and positive end-expiratory pressure (PEEP). Group 1 animals (n = 6) were ventilated with a PEEP of 3 cm H2O and a tidal volume of 15 mL/kg, which generated an end-inspiratory transpulmonary pressure of < or = 15 cm H2O. In group 2(n = 6), tidal volume was adjusted to generate a transpulmonary pressure of 35 cm H2O and PEEP was set to 3 cm H2O. In group 3(n = 6), tidal volume was also adjusted to yield a transpulmonary pressure of 35 cm H2O but PEEP was set to 10 cm H2O. In each group, we instilled approximately 10(8) colony-forming units of E. coli into the trachea of the dogs and ventilated them with the chosen tidal volume and PEEP for 6 hrs afterward.

MEASUREMENTS AND MAIN RESULTS

We measured the pressure-volume relationship (pressure-volume curve) of the respiratory system before and 6 hrs after bacterial instillation. We obtained blood cultures before and 0.5, 1,2,3,4,5, and 6 hrs after bacterial instillation. After 6 hrs, the lungs were removed for histologic (histologic score) and gravimetric (wet-to-dry weight ratio, WW/DW) analysis. During the experiment 0, 5, and 1 dogs developed positive blood cultures in groups 1, 2, and 3, respectively. The number of dogs that developed bacteremia in group 2 was significantly greater than in the other two groups (p < .05). In group 1, pressure-volume curves demonstrated a lower inflection point which was greater than the end-inspiratory transpulmonary pressure suggesting that low transpulmonary pressure/low PEEP strategy ventilated aerated regions without expanding atelectatic areas. In group 2, pressure-volume curves demonstrated both a lower inflection point and an upper deflection point which were spanned by the tidal volume, suggesting that high transpulmonary pressure/low PEEP strategy might have caused both overdistention and cyclic closure and reopening. In group 3, pressure-volume curves demonstrated only a upper deflection point which was less than the maximal alveolar tidal pressure. At the end of the experimental protocol, group 2 manifested the most lung injury as assessed by gravimetric and histologic indices of lung injury. WW/DW of group 2(13.1 +/- 1.0 (SD); p < .05) was greater than groups 1 and 3(7.5 +/- 1.2 and 8.6 +/- 1.0, respectively). Similarly, the overall weighted histologic injury score for group 2 (1.19 +/- 0.26; p < .02) was greater than for groups 1 and 3 (0.82 +/- 0.20 and 0.88 +/- 0.22, respectively). For groups 2 and 3, the overall weighted histologic injury scores of the dependent regions were greater than the nondependent regions (p < .004).

CONCLUSIONS

We conclude that the ventilatory strategy most likely to overdistend the lungs while allowing repetitive opening and closure of alveoli (group 2) facilitated bacterial translocation from the alveoli to the bloodstream and increased lung injury, as determined by histologic and gravimetric analysis. PEEP ameliorated these effects, despite lung overdistention, but increased histologic and gravimetric indices of lung injury in dependent as compared with the nondependent regions.

Pulmonary artery catheters in cardiovascular disease

OBJECTIVE

To review the literature addressing the use of the pulmonary artery catheter (PAC) in patients with cardiovascular disease.

DATA SOURCE

All pertinent English language articles dealing with pulmonary artery catheterization in patients with cardiovascular disease were retrieved from 1976 through 1996.

STUDY SELECTION

Articles were chosen for review if the use of pulmonary artery catheterization in patients with cardiovascular disease was studied or reviewed.

DATA EXTRACTION

From the articles selected, information was obtained about changes in therapy and changes in outcome associated with PAC use in patients with cardiovascular disease.

DATA SYNTHESIS

Whether enhanced understanding of patient hemodynamics translates into definable benefits for those patients has recently come into question. Although there are a number of conventional clinical indications for pulmonary artery catheterization, and several studies have shown that catheterization prompts changes in therapy in many patients, most data regarding outcomes are retrospective; prospective randomized trials are lacking. Nonetheless, we believe, based on the available evidence and the preponderance of expert opinion, that management with the PAC improves outcome in several patient populations. These populations include: a) patients with acute myocardial infarction either complicated by cardiogenic shock or progressive hypotension, or associated with mechanical complications; b) patients with congestive heart failure refractory to empiric therapy; c) patients with pulmonary hypertension; and d) patients with shock or hemodynamic instability.

CONCLUSION

Pulmonary artery catheterization is often used to optimize patient management, although this may not be demonstrable in terms of prospective trials using mortality or other "hard" outcome measures. Nonetheless, more rapid diagnosis and achievement of therapeutic endpoints guided by PAC use can decrease morbidity and intensive care days.

Appropriate helicopter transport of urban trauma patients

OBJECTIVE

Inappropriate use of helicopter transport of trauma patients in urban areas increases costs, risk of injury, and unavailability for appropriate flights. We evaluated the effect of an emergency medical service (EMS) system audit of helicopter trauma scene flights (TSFs) on appropriateness of TSFs.

METHODS AND DESIGN

Retrospective cohort.

SETTING

Defined urban area with two Level I trauma hospitals.

PARTICIPANTS

Consecutive TSFs 2 years before (PRE) and 2 years after (POST) audit.

INTERVENTION

EMS system audit established criteria for appropriate TSFs.

MAIN RESULTS

The total number of trauma system entries were similar for the two periods: PRE (1989) = 2862; POST (1990 and 1991) = 2787 and 2772. The total number of TSFs decreased after audit (PRE = 122; POST = 50). The proportion of inappropriate (INAPPRO)/total TSFs did not change (62% vs. 66%; chi 2 = 0.04; p = 0.85). There was no difference between appropriate (APPRO) and INAPPRO TSFs for mean vital signs, mechanism of injury, Trauma and Injury Severity Score (TRISS) and Injury Severity Score (ISS), mean length of stay, and proportion of survivors. Scene and transport time intervals were similar. For both PRE and POST periods, 26 APPRO patients (45%) were admitted to non-intensive care unit wards.

CONCLUSIONS

An EMS system audit with general awareness of audit criteria decreased the total number of TSFs and hence the number of INAPPRO TSFs in this urban trauma system population. However, the proportion of TSFs that were considered INAPPRO did not change. Criteria for urban TSFs should be based on markers of critical physiologic patient status matched to unique care that the helicopter personnel can provide (e.g., advanced airway management).

Parenchymal cytokine expression precedes clinically observed ischemia in dorsal flaps in the rat

Cytokines have been implicated as pivotal mediators of the wound-healing process. An understanding of the production and interaction of cytokines may lead to a better appreciation of the complex mechanisms of flap ischemia. The potential would then exist for novel diagnostic and therapeutic approaches to prevent and reverse damage to the endangered flap. The goal of this study was to determine the expression of parenchymal cytokines at various time points during flap ischemia. Punch biopsies were obtained from McFarlane dorsal flaps in the Sprague-Dawley murine model. We examined cytokine mRNA profiles for interleukin 1 alpha (IL-1 alpha), IL-2, IL-6, basic fibroblast growth factor (b-FGF), gamma-interferon (gamma IFN), transforming growth factor beta (TGF-beta), and platelet-derived growth factor A chain (PDGF-alpha) using in situ hybridization. Samples were taken from 0 to 48 hours postoperatively, with n = 3 for each time point. Eight hours postoperatively there was an abrupt peak of parenchymal cytokine expression at the bases of the flaps. Clinically at this time the flaps appeared completely viable without evidence of ischemic change. Leukocyte cytokine production peaked at 16 hours, when distal flap ischemia was evident clinically. These findings demonstrate an early peak of cytokine expression prior to clinical evidence of ischemia.

The effect of antenatal surgery on craniofacial growth in sheep model

The purpose of this investigation was to evaluate the effect of antenatal palatal surgery in a sheep model. At 75 to 90 days of gestation, 20 fetuses underwent surgical in utero manipulation of their palates with the incision and elevation of bilateral bipedicled mucoperiosteal flaps. Sixteen of the 20 sheep (80 percent) went on to a normal full-term delivery. The palates and facial appearances were grossly evaluated, and detailed measurements were made of the palates. The data underwent statistical analysis. We were unable to discern any differences between the experimental group and the age-matched controls. Antenatal palatal surgery appeared to have no effect on craniofacial growth and development.

Repair of experimental calvarial defects with Bio-Oss particles and collagen sponges in a rabbit model

Various materials have been used for reconstruction of both acquired and congenital calvarial defects. Unfortunately, each has its limitations. Autologous bone grafts have irregular rates of resorption that may require secondary corrective surgery, and individual harvest sites have limited stores that can necessitate additional donor locations. Alloplastic materials have unlimited quantities and volume stability but they may not become incorporated and are associated with a higher incidence of infection. The optimal bone substitute should stimulate new bone formation and permanently supplant the temporary space filler, thereby reconstituting the surgical defect. We evaluated 2 newly available bone substitutes, resorbable natural bone mineral (Bio-Oss particles) and a combination of collagen and natural bone mineral collagen combination (Bio-Oss sponges), to repair calvarial defects in an adult, male, New Zealand white rabbit model. We found that the particulate Bio-Oss material resorbed and then underwent the normal physiological stages of bone remodeling. The collagen and Bio-Oss combination was replaced by new bone ingrowth. These materials may have potential for use in the reconstruction of skull defects.

Effect of insulin-like growth factor-1 on zygomatic arch bone regeneration: a preliminary histological and histometric study

A number of physicians have attempted to pharmacologically manipulate the healing of bony fractures with a variety of agents such as growth hormone, thyroxine, chondroitin sulfate, and parathyroid hormone. Thus far, results from these experiments have been inconclusive. Previous research dealing with insulin-like growth factors has centered on cultures of osteoblast-like cells and has demonstrated a stimulatory effect on bone collagen synthesis, which may in fact play a critical role in the process of bone formation itself. The purpose of this investigation was to examine the effects of a genetically engineered growth factor, insulin growth factor type I, on midfacial fracture healing. In 24 adult male Sprague-Dawley rats, a standardized defect was created within the midportion of each zygomatic arch. One-half were treated with insulin growth factor type I administered with an osmotic infusion pump and the other half served as control subjects. At 2, 4, 8, and 12 weeks, animals from each group were killed and specimens of the defect obtained. Data were collected from radiographs and histological studies to compare the extent of bony repair. From this study, it appears that insulin growth factor type I could exert a potentiating effect on the repair of midfacial bone defects.

Detection of proliferating cell nuclear antigen in gliomas and adjacent resection margins

We describe a technique for estimating the number of proliferating cells in gliomas and adjacent resection cavities after tumor removal. Proliferating cell nuclear antigen (PCNA) is a nuclear protein associated with the cell cycle. Anti-PCNA antibody staining provides a semiquantitative estimate of the number of proliferating cells found in fixed tissue embedded in paraffin. The extent of the staining of tumor cells of glioblastoma multiforme, anaplastic astrocytomas, low-grade gliomas, and other lesions of the brain with anti-PCNA antibody is correlated with the histological diagnosis. In addition, the labeling of the margins after resection of gliomas and other lesions with anti-PCNA antibody is also associated with the histological diagnosis of the lesion. This technique may be useful in estimating the "biological" extent of resection and in predicting the recurrence patterns of gliomas.

Polyglyconate plates and screws to stabilize zygomatic osteotomies in a rabbit model

Rigid internal fixation with miniplates and screws continues to be widely used in the correction of both congenital and acquired craniomaxillofacial deformities. This technique allows precise three-dimensional stabilization of bony segments. A number of recent reports have detailed some disadvantages, including potential growth restriction in developing children, bone resorption, infection, extrusion, and palpability. These problems have often necessitated secondary surgery for hardware removal. A biodegradable plate and screw system would eliminate these potential and real problems. Over the last 2 decades, there has been an escalating interest in developing satisfactory biodegradable materials for bony fixation. We have previously reported the initial phases of a long-term evaluation of various biomaterials currently available. The purpose of this study is to examine a biodegradable plate and screw system fabricated from a faster resorbing material--polyglyconate. This system would be applicable to pediatric reconstructive problems. Earlier studies have shown its tissue compatibility and feasibility for multiple surgical uses. Osteotomies were created at the midpoint of each zygomatic arch of 42 adult male white New Zealand rabbits. The animals were then divided into two equal groups. The first group served as a control and the bony segments were permitted to heal without stabilization, whereas in the experimental group, the bony segments were stabilized with biodegradable plates and screws made from polyglyconate. Animals were then sacrificed at 2, 4, 6, 8, 12, and 16 weeks, at which time radiographs were obtained. Zygomatic complexes were then removed en bloc, and routine hematoxylin and eosin slides were made for light microscopy. Without fixation, fracture segments became significantly displaced.(ABSTRACT TRUNCATED AT 250 WORDS)

Midfacial fracture repair in the adult rat

The consensus in the literature is that fracture healing within the midface occurs via fibrous union. Clinical experience with the surgical correction of established traumatic deformities has not borne this out. An earlier histological examination with human biopsy specimens demonstrated that eventually repair occurred by direct bony union. However, a recent study in a rabbit model challenged this conclusion and indicated that the process of new formation resembles secondary bone formation as in endochondral formed bone. The purpose of our inquiry is to elucidate further the process of midfacial bony repair in an adult male Sprague-Dawley rat model.

Biomechanics of indirect reduction of bone retropulsed into the spinal canal in vertebral fracture

The biomechanics of indirect reduction of bone fragments retropulsed into the spinal canal in a burst fracture were investigated. In this model, tunnels were created in vertebrae L1 and C5 oriented anterior-to-posterior, allowing access to the posterior longitudinal ligament. A probe containing a load-sensing tip was passed through the tunnel. Both the location of the tip and the load acting on it by posterior deflection of the posterior longitudinal ligament were measured. In the lumbar spine, distraction was applied by spinal instrumentation that also permitted independent kyphotic-lordotic alignment of the vertebrae. In the cervical spine, axial traction was applied through direct loading. Several clinically relevant observations were made. It was not possible to produce an anteriorly directed force in the posterior longitudinal ligament at less than 35% canal occlusion, partly because the posterior longitudinal ligament stands away from the midbody of the vertebra. Distractive forces of up to 150 N were applied in the lumbar spine, which were nearly equal to the tensile breaking strength of the isolated posterior longitudinal ligament. Regardless of the relative sagittal plane angulation of the vertebrae, distraction was the governing factor in generating force in the posterior longitudinal ligament. Because positioning the vertebrae in lordosis before applying distraction significantly slackens the posterior longitudinal ligament, it is suggested that distraction be applied before angular positioning of the vertebrae is performed.

Reconstruction of calvarial defects with anorganic bovine bone mineral (Bio-Oss) in a rabbit model

Reconstructive surgeons have employed various procedures using either autogenous or alloplastic materials to repair cranial defects secondary to trauma, extirpative surgery, or congenital anomalies. Currently, the choice appears to be dependent on the personal choice or background of the operating surgeon. For years, our preference has been to use calvarial bone grafts as our primary source of reconstructive material. Disadvantages include uneven resorption of the bone grafts and limited quantities. For these reasons, bony substitutes present new possibilities for reconstruction of craniomaxillofacial defects. We evaluated Bio-Oss, which is a natural bone mineral derived from a bovine source that is chemically and physically identical to human bone, as a possible replacement material to reconstruct skull defects in a rabbit model.

The effect of insulin growth factor-1 on calvarial sutures in a Sprague-Dawley rat

Early investigations attempting to determine the exact pathogenesis of premature closure of the cranial sutures were limited by the untoward sequelae caused by surgical procedures in animal models to simulate the development of craniosynostosis. In an attempt to create a model for evaluating the effects of manipulating the craniofacial sutures without the limitations of associated scarring, we conceived an animal prototype dependent on the effects of insulin growth factor-1 on the anterior frontal suture in a Sprague-Dawley rat model. The experimental group received 2 mg of IGF-1 over a 14-day period via a subcutaneously placed osmotic infusion pump, whereas the age-matched control group received no treatment. We present our preliminary histological results describing the effect of IGF-1 on calvarial sutures.

Surgical correction of unilateral lambdoid synostosis: occipital rotation flap

Virchow (1851) is credited with initially describing calvarial development following premature closure of individual sutures. He noted that resultant compensatory growth occurred perpendicular to the fused suture, resulting in asymmetrical calvarial development. Lambdoid synostosis, whether unilateral, bilateral, or associated with other cranial fusions, is reasonably uncommon. Previous authors report an incidence of less than 10% of all reported cases of premature fusion of the calvarial or skull base sutures. We report 27 patients (20 boys, 7 girls) ranging in age from 3 months to 8 years with unilateral lambdoid craniosynostosis followed over a three-year period. In 19 patients, calvarial reshaping was performed by repositioning a parietooccipital bone flap stabilized with lag-screw fixation to provide an increased radius of curvature to the affected area and to reestablish the resultant craniectomy between the parietooccipital junction and into the posterior fossa retromastoid occipital bone as an appropriate site for growth. Indications for one-stage calvarial reshaping included untreated lambdoid stenosis in older children or a failed simple lambdoid synostectomy after approximately 18 months. Each child experienced significant improvement in calvarial shape and ipsilateral ear position. Although we had no operative complications, two children underwent a second outpatient procedure for removal of hardware palpated by their parents.

Susceptibilities of genital mycoplasmas to the newer quinolones as determined by the agar dilution method

The increasing resistance of genital mycoplasmas to tetracycline poses a problem because tetracycline is one of the few antimicrobial agents active against Mycoplasma hominis, Ureaplasma urealyticum, chlamydiae, gonococci, and other agents of genitourinary-tract disease. Since the quinolones are a promising group of antimicrobial agents, the susceptibilities of M. hominis and U. urealyticum to the newer 6-fluoroquinolones were determined by the agar dilution method. Ciprofloxacin, difloxacin, and ofloxacin had good activity against M. hominis, with the MIC for 50% of isolates tested (MIC50) being 1 microgram/ml. Fleroxacin, lomefloxacin, pefloxacin, and rosoxacin had MIC50s of 2 micrograms/ml. Enoxacin, norfloxacin, and amifloxacin had MIC50s of 8 to 16 micrograms/ml, and cinoxacin and nalidixic acid were inactive (MIC50, greater than or equal to 256 micrograms/ml). Overall, the activities of 6-fluoroquinolones for ureaplasmas were similar to those for M. hominis, with MICs being the same or twofold greater. The most active 6-fluoroquinolones against ureaplasmas were difloxacin, ofloxacin, and pefloxacin, with MIC50s of 1 to 2 micrograms/ml. Ciprofloxacin was unusual in that the MIC50 for M. hominis was 1 microgram/ml, whereas the MIC50 for ureaplasmas was 8 micrograms/ml. Since the MIC50s for the most active quinolones approximate achievable concentrations in blood and urine, quinolones have promise in treating mycoplasmal infections.

Lactate dehydrogenase isoenzyme-1 in serum for detection of peri-operative myocardial infarction after cardiac surgery

We prospectively studied changes in serum lactate dehydrogenase isoenzyme-1 (LD-1, EC 1.1.1.27) in 99 consecutive patients after either coronary artery bypass grafting (CABG, n = 61), isolated cardiac-valve replacement (n = 24), or the two procedures combined (n = 14); 86 of these had no clinical evidence of peri-operative myocardial infarction (MI). Blood was sampled immediately after surgery and at 6-h intervals for up to 42 h thereafter. LD-1 was isolated by using the LD M-subunit antiserum. Samples from the non-MI patients were used to establish the reference intervals for LD-1. By 24 h after surgery, mean serum LD-1 values were higher (P less than 0.001) in non-MI patients who underwent isolated valve replacement (222 +/- 74 U/L) or combined CABG and valve replacement (266 +/- 58 U/L) than in 50 non-MI patients who underwent CABG alone (134 +/- 42 U/L). Separate reference intervals were determined for CABG and other patients at each sampling time. By 24 h after operation, LD-1 exceeded these reference intervals in the 10 CABG and two combined-procedure patients in whom other evidence of MI was present. Measurement of LD-1 24 to 42 h after cardiac surgery appears to be a useful test for the diagnosis of perioperative MI.

Lactate dehydrogenase isoenzyme-1 in serum for detection of peri-operative myocardial infarction after cardiac surgery

We prospectively studied changes in serum lactate dehydrogenase isoenzyme-1 (LD-1, EC 1.1.1.27) in 99 consecutive patients after either coronary artery bypass grafting (CABG, n = 61), isolated cardiac-valve replacement (n = 24), or the two procedures combined (n = 14); 86 of these had no clinical evidence of peri-operative myocardial infarction (MI). Blood was sampled immediately after surgery and at 6-h intervals for up to 42 h thereafter. LD-1 was isolated by using the LD M-subunit antiserum. Samples from the non-MI patients were used to establish the reference intervals for LD-1. By 24 h after surgery, mean serum LD-1 values were higher (P less than 0.001) in non-MI patients who underwent isolated valve replacement (222 +/- 74 U/L) or combined CABG and valve replacement (266 +/- 58 U/L) than in 50 non-MI patients who underwent CABG alone (134 +/- 42 U/L). Separate reference intervals were determined for CABG and other patients at each sampling time. By 24 h after operation, LD-1 exceeded these reference intervals in the 10 CABG and two combined-procedure patients in whom other evidence of MI was present. Measurement of LD-1 24 to 42 h after cardiac surgery appears to be a useful test for the diagnosis of perioperative MI.

Management of Reye's syndrome. A rational approach to a complex problem

Five patients suffering from progressive Reye's syndrome were aggressively treated in our ICU. Our protocol consisted of endotracheal intubation, curarization, mechanical ventilation, hypothermia to 31 degrees C, and fluid restriction. Intracranial pressure (ICP) was monitored and remained below 10-20 torr in all patients except one in whom ICP rose only once (for a few minutes) to 27 torr. Pulmonary artery wedge pressure was monitored in 4 patients and was maintained at 4-5 torr. Duration of active intervention as outlined above was 3-4 days. All 5 patients started with clinical stage IV and EEG grade IV or worse. Four patients had complete recovery and one died. In this group of patients, high ICP was not a feature of the disease. We recommend that use of mannitol for active dehydration be reserved for cases with proven rise in ICP, in which case hemodynamics should be carefully monitored.

Studies on the Antigenic Properties of the Ultraviruses

No evidence of specific complement fixing antibodies against the virus of herpes was found in the serum of rabbits which had been immunized by different routes with virus-brain suspensions. These immune sera also failed to present any evidence of specific precipitating antibodies. Virulicidal antibodies were demonstrable in all of the immune sera tested for this property.