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1.
Educ Prim Care ; 33(6): 360-363, 2022 11.
Article in English | MEDLINE | ID: mdl-36066115

ABSTRACT

The COVID-19 pandemic has profoundly impacted the way general practice is run and this is expected to have had a knock-on effect upon GP training. A questionnaire-based study was designed to investigate what was happening to GP trainees 16 months into the pandemic in terms of opportunities to develop clinical experience and clinical decision-making. We also asked trainers and trainees for ideas on how we might mitigate for the effects of COVID-19. In particular, there has been decreased exposure to clinical examination during the pandemic and there appear to be gaps in opportunities to learn from urgent and unscheduled care settings and to develop skills in rapid clinical decision-making. It is interesting to consider what general practice will look like when the pandemic is over and how this will this affect the GP training curriculum going forwards. Although response rates were low, we were able to determine some emerging themes for national, local and educational review going forwards to help shape and improve GP training for the future.


Subject(s)
COVID-19 , General Practice , Humans , Pandemics , General Practice/education , Curriculum , Family Practice/education
2.
Anaesthesia ; 74(3): 300-311, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30536369

ABSTRACT

The anaesthesia practice in children observational trial of 31,127 patients in 261 European hospitals revealed a high (5.2%) incidence of severe critical events in the peri-operative period and wide variability in practice. A sub-analysis of the UK data was undertaken to investigate differences compared with the non-UK cohort in the incidence and nature of peri-operative severe critical events and to attempt to identify areas for quality improvement. In the UK cohort of 7040 paediatric patients from 43 hospitals, the overall incidence of peri-operative severe critical events was lower than in the non-UK cohort (3.3%, 95%CI: 2.9-3.8 vs. 5.8%, 95%CI: 5.5-6.1, RR 0.57, p < 0.001). There was a lower rate of bronchospasm (RR 0.22, 95%CI: 0.14-0.33; p < 0.001), stridor (RR 0.42, 95%CI: 0.28-0.65; p < 0.001) and cardiovascular instability (RR 0.69, 95%CI: 0.55-0.86; p = 0.001) than in the non-UK cohort. The proportion of sicker patients where less experienced teams were managing care was lower in the UK than in the non-UK cohort (10.4% vs. 20.4% of the ASA physical status 3 and 9% vs. 12.9% of the ASA physical status 4 patients). Differences in work-load between centres did not affect the incidence and outcomes of severe critical events when stratified for age and ASA physical status. The lower incidence of cardiovascular and respiratory complications could be partly attributed to more experienced dedicated paediatric anaesthesia providers managing the higher risk patients in the UK. Areas for quality improvement include: standardisation of serious critical event definitions; increased reporting; development of evidence-based protocols for management of serious critical events; development and rational use of paediatric peri-operative risk assessment scores; implementation of current best practice in provision of competent paediatric anaesthesia services in Europe; development of specific training in the management of severe peri-operative critical events; and implementation of systems for ensuring maintenance of skills.


Subject(s)
Anesthesia , Perioperative Care , Adolescent , Bronchial Spasm/epidemiology , Cardiovascular Diseases/epidemiology , Child , Child, Preschool , Female , Humans , Incidence , Infant , Prospective Studies , Quality Improvement , Respiratory Sounds , United Kingdom
3.
Anaesthesia ; 72 Suppl 1: 84-94, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28044332

ABSTRACT

A narrative review was carried out to identify articles on monitoring of teamwork, with particular relevance to anaesthetists. The papers reviewed showed that team monitoring takes place both implicitly and explicitly in the anaesthetic environment. No single optimal model of teamwork monitoring for all situations was identified. Most of the studies identified were of a pre-intervention, post-intervention design, without randomisation or control group. Information shared during a formal briefing is more likely to be recalled, and provides a basis for a shared team mental model. A number of studies appeared to show that targeted teamwork training has a positive impact on both teamwork and patient safety.


Subject(s)
Anesthetists , Patient Care Team , Communication , Cooperative Behavior , Humans , Patient Safety , Teaching
4.
J Perioper Pract ; 25(9): 155-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26677517

ABSTRACT

The aim of this study was to identify the cognitive non-technical skills (i.e. situation awareness and decision making) used by anaesthetic assistants, as part of the development of a specialty-specific behavioural rating system for anaesthetic assistants. Semi-structured interviews were conducted with anaesthetic assistants (n=22), anaesthetic consultants (n=11) and trainee anaesthetists (n=12) in Scotland. The interviews were transcribed and thematically analysed. All 45 participants described the presence or failure of situation awareness (i.e. gathering information, its comprehension and anticipation) in 713 phrases. Decision making (i.e. considering options, selecting actions and reviewing decisions) by the anaesthetic assistants was reported much less frequently--only 34 participants described 89 phrases. Situation awareness is a key non-technical skill used by anaesthetic assistants, however decision making was less commonly described as required by anaesthetic assistants. This provides qualitative data to support the development of a non-technical skills taxonomy for anaesthetic assistants.


Subject(s)
Anesthesiology , Cognition , Professional Competence , Humans , Interviews as Topic , Scotland , Workforce
5.
Anaesthesia ; 70(8): 907-14, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26152252

ABSTRACT

This study tested the reliability, validity and usability of a prototype behavioural rating system for the non-technical skills of assistants working with the anaesthetist. Anaesthetic nurses and operating department practitioners (n = 48) used the prototype Anaesthetic Non-technical Skills for Anaesthetic Practitioners (ANTS-AP) system to rate the non-technical skills of anaesthetic assistants in 12 videos of simulated theatre work. Test-retest reliability was assessed with a sub-sample (n = 12). The skill categories assessed were 'situation awareness', 'teamwork and communication' and 'task management'. The internal consistency for the ratings of elements in categories was acceptable (Cronbach's α of 0.78, 0.77 and 0.69, respectively), with more modest inter-rater reliability (intraclass correlations for categories 0.54, 0.70, 0.86), test-retest reliability (intraclass correlations 0.68, 0.58, 0.38) and accuracy (weighted kappa 0.39). Most participants considered the system complete (n = 42, 87%), the wording clear (n = 48, 100%) and the system useful for structuring observation (n = 48, 100%).


Subject(s)
Anesthesiology/standards , Behavior , Clinical Competence/standards , Personnel, Hospital/standards , Surveys and Questionnaires/standards , Female , Humans , Male , Reproducibility of Results , Scotland
6.
Anaesth Intensive Care ; 43(4): 512-7, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26099766

ABSTRACT

The outcome of critical incidents in the operating theatre has been shown to be influenced by the behaviour of anaesthetic technicians (ATs) assisting anaesthetists, but the specific non-technical skills involved have not been described. We performed a review of critical incidents (n=1433) reported to the Australian Incident Monitoring System between 2002 and 2008 to identify which non-technical skills were used by ATs. The reports were assessed if they mentioned anaesthetic assistance or had the boxes ticked to identify "inadequate assistance" or "absent supervision or assistance". A total of 90 critical incidents involving ATs were retrieved, 69 of which described their use of non-technical skills. In 20 reports, the ATs ameliorated the critical incident, whilst in 46 they exacerbated the critical incident, and three cases had both positive and negative non-technical skills described. Situation awareness was identified in 39 reports, task management in 23, teamwork in 21 and decision-making in two, but there were no descriptions of issues related to leadership, stress or fatigue management. Situation awareness, task management and teamwork appear to be important non-technical skills for ATs in the development or management of critical incidents in the operating theatre. This analysis has been used to support the development of a non-technical skills taxonomy for anaesthetic assistants.


Subject(s)
Anesthesiology/statistics & numerical data , Clinical Competence/statistics & numerical data , Operating Room Technicians/statistics & numerical data , Risk Management/statistics & numerical data , Australia , Clinical Competence/standards , Humans , Medical Errors/statistics & numerical data , Operating Room Technicians/standards , Operating Rooms/standards , Operating Rooms/statistics & numerical data , Risk Management/methods
7.
Injury ; 45(9): 1422-8, 2014 Sep.
Article in English | MEDLINE | ID: mdl-22613453

ABSTRACT

BACKGROUND: Complex lower limb injury caused by improvised explosive devices (IEDs) has become the signature wounding pattern of the conflict in Afghanistan. Current classifications neither describe this injury pattern well, nor correlate with management. There is need for a new classification, to aid communication between clinicians, and help evaluate interventions and outcomes. We propose such a classification, and present the results of an initial prospective evaluation. PATIENTS AND METHODS: The classification was developed by a panel of military surgeons whilst deployed to Camp Bastion, Afghanistan. Injuries were divided into five classes, by anatomic level. Segmental injuries were recognised as a distinct entity. Associated injuries to the intraperitoneal abdomen, genitalia and perineum, pelvic ring, and upper limbs, which impact on clinical management and resources, were also accounted for. RESULTS: Between 1 November 2010 and 20 February 2011, 179 IED-related lower limb injuries in 103 consecutive casualties were classified, and their subsequent vascular and musculoskeletal treatment recorded. 69% of the injuries were traumatic amputations, and the remainder segmental injuries. 49% of casualties suffered bilateral lower limb amputation. The most common injury was class 3 (involving proximal lower leg or thigh, permitting effective above-knee tourniquet application, 49%), but more proximal patterns (class 4 or 5, preventing effective tourniquet application) accounted for 18% of injuries. Eleven casualties had associated intraperitoneal abdominal injuries, 41 suffered genital or perineal injuries, 9 had pelvic ring fractures, and 66 had upper limb injuries. The classification was easy to apply and correlated with management. CONCLUSIONS: The 'Bastion classification' is a pragmatic yet clinically relevant injury categorisation, which describes current injury patterns well, and should facilitate communication between clinicians, and the evaluation of interventions and outcomes. The validation cohort confirms that the injury burden from IEDs in the Helmand Province of Afghanistan remains high, with most casualties sustaining amputation through or above the knee. The rates of associated injury to the abdomen, perineum, pelvis and upper limbs are high. These findings have important implications for the training of military surgeons, staffing and resourcing of medical treatment facilities, to ensure an adequate skill mix to manage these complex and challenging injuries.


Subject(s)
Amputation, Traumatic/surgery , Blast Injuries/surgery , Leg Injuries/surgery , Military Medicine , Military Personnel , Multiple Trauma/surgery , Afghan Campaign 2001- , Amputation, Traumatic/classification , Blast Injuries/classification , Blast Injuries/physiopathology , Emergency Medicine/education , Emergency Medicine/methods , Humans , Injury Severity Score , Leg Injuries/classification , Leg Injuries/physiopathology , Military Medicine/education , Military Medicine/methods , Military Personnel/statistics & numerical data , Pelvis/injuries , Perineum/injuries , Prospective Studies , Tourniquets
8.
J Environ Manage ; 127: 268-77, 2013 Sep 30.
Article in English | MEDLINE | ID: mdl-23771202

ABSTRACT

Nitrogen loads to several New Zealand lakes are dominated by nonpoint runoff from pastoral farmland which adversely affects lake water quality. A 'cap and trade' scheme is being considered to help meet targets set for nitrogen loads to Lake Rotorua, and a numerical model, NTRADER, has been developed to simulate and compare alternative schemes. NTRADER models both the geophysics of nitrogen generation and transport, including groundwater lag times, and the economics of 'cap and trade' schemes. It integrates the output from several existing models, including a farm-scale nitrogen leaching and abatement model, a farm-scale management economic model, and a catchment-scale nitrogen transport model. This paper details modeling methods and compares possible trading program design features for the Lake Rotorua catchment. Model simulations demonstrate how a cap and trade program could be used to effectively achieve challenging environmental goals in the targeted catchment. However, results also show that, due to complex hydrogeology, satisfactory environmental outcomes may be not achieved unless groundwater lag times are incorporated into the regulatory scheme. One way to do this, as demonstrated here, would be to explicitly include lag times in the cap and trade program. The utility of the model is further demonstrated by quantifying relative differences in abatement costs across potential regulatory schemes.


Subject(s)
Lakes/chemistry , Models, Theoretical , Nitrogen/analysis , Water Pollutants, Chemical/analysis , Groundwater/chemistry , New Zealand , Nitrogen/chemistry , Water Pollutants, Chemical/chemistry
9.
Environ Sci Process Impacts ; 15(6): 1137-52, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23652422

ABSTRACT

High-frequency sampling of two major stream inflows to a large eutrophic lake (Lake Rotorua, New Zealand) was conducted to measure inputs of total suspended sediment (TSS), and fractions of nitrogen and phosphorus (P). A total of 17 rain events were sampled, including three during which both streams were simultaneously monitored to quantify how concentration-discharge (Q) relationships varied between catchments during similar hydrological conditions. Dissolved inorganic nitrogen (DIN) concentrations declined slightly during events, reflecting dilution of groundwater inputs by rainfall, whereas dissolved inorganic P (PO4-P) concentrations were variable and unrelated to Q, suggesting dynamic sorptive behaviour. Event loads of total nitrogen (TN) were predominantly DIN, which is available for immediate uptake by primary producers, whereas total phosphorus (TP) loads predominantly comprised particulate P (less labile). Positive correlations between Q and concentrations of TP (and to a lesser extent TN) reflected increased particulate nutrient concentrations at high flows. Consequently, load estimates based on hourly Q during storm events and concentrations of routine monthly samples (mostly base flow) under-estimated TN and TP loads by an average of 19% and 40% respectively. Hysteresis with Q was commonly observed and inclusion of hydrological variables that reflect Q history in regression models improved predictions of TN and TP concentrations. Lorenz curves describing the proportions of cumulative load versus cumulative time quantified temporal inequality in loading. In the two study streams, 50% of estimated two-year loads of TN, TP and TSS were transported in 202-207, 76-126 and 1-8 days respectively. This study quantifies how hydrological and landscape factors can interact to influence pollutant flux at the catchment scale and highlights the importance of including storm transfers in lake loading estimates.


Subject(s)
Geologic Sediments/analysis , Lakes/chemistry , Nitrogen/analysis , Phosphorus/analysis , Rivers/chemistry , Environmental Monitoring , Rain/chemistry , Water Movements
10.
Clin Microbiol Infect ; 19(12): 1174-80, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23438068

ABSTRACT

A number of different methods exist to assess clinical stability, a key component of pneumonia management. We compared the prognostic value of different stability criteria through a secondary analysis of the Edinburgh pneumonia study database. We studied four clinical stability criteria (Halm's criteria, the ATS criteria, CURB and 50% or more decrease in C-reactive protein from baseline). Outcomes included 30-day mortality, need for mechanical ventilation or vasopressor support (MV/VS), development of a complicated pneumonia, and a combined outcome of the above. A total of 1079 patients (49.8% male), with a median age of 68 years (IQR 53-80), were included. Ninety-three patients (8.6%) died by day 30, 91 patients (8.4%) required MV/VS and 99 patients (9.2%) developed a complicated pneumonia. Patients with increasing severity of pneumonia on admission, assessed by both CURB-65 and PSI, took a progressively longer time to achieve clinical stability assessed by any method (p < 0.001 for all criteria). Halm's criteria had the highest area under the curve (AUC) for prediction of 30-day mortality (AUC 0.95 (0.94-0.96)), need for MV/VS (AUC 0.96 (0.95-0.97)) and combined adverse outcome (AUC 0.96 (0.95-0.97)). C-reactive protein had the highest area under the curve for complicated pneumonia (AUC 0.96 (0.95-0.97)). Adding C-reactive protein to Halm's criteria increased the area under the curve, but the difference was only statistically significant for complicated pneumonia. All of the criteria performed well in predicting adverse outcomes in patients with pneumonia. Halm's criteria performed best when identifying patients at low risk of complications.


Subject(s)
Community-Acquired Infections/diagnosis , Community-Acquired Infections/mortality , Pneumonia/diagnosis , Pneumonia/mortality , Aged , C-Reactive Protein/metabolism , Community-Acquired Infections/therapy , Female , Hospitalization , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Pneumonia/complications , Pneumonia/therapy , Prognosis , Prospective Studies , Respiration, Artificial , Severity of Illness Index
11.
Placenta ; 34 Suppl: S3-5, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23206905

ABSTRACT

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, three of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of models and technical issues involved in placenta research: 1) comparative placentation and animal models; 2) advanced techniques in placental histopathology; 3) human pluripotent stem cells as a model for trophoblast differentiation.


Subject(s)
Cell Differentiation/physiology , Models, Animal , Placenta/pathology , Placentation/physiology , Pluripotent Stem Cells/physiology , Trophoblasts/physiology , Animals , Female , Humans , Placenta/cytology , Pregnancy
12.
J Environ Qual ; 41(5): 1681-9, 2012.
Article in English | MEDLINE | ID: mdl-23099960

ABSTRACT

When wetlands are disturbed by cattle, pulses of contaminants may be released. We studied nitrogen exports from a small pastoral wetland (1725 m) in the Lake Taupo Catchment, New Zealand, to which cattle and sheep had periodic access. Flow, turbidity, and water quality samples were collected at the wetland outlet over 2 yr. Turbidity was used to trigger sampling during livestock grazing and as a surrogate for organic N (OrgN) and total N (TN) in flux estimation. The wetland flowed throughout the study (median 0.285 L s) and was baseflow dominated (73%) but responded to rainfall (peak storm flow 166 L s). Organic N was the dominant N form exported (median OrgN:TN ratio 0.86). During cattle grazing periods, concentrations and fluxes of all forms of nitrogen at the outlet were elevated compared with storm and baseflow conditions during nongrazed periods. The TN fluxes were nine times greater when cattle grazed the wetland (306 g d) than under nongrazed baseflow conditions (32 g d). Cattle grazing occurred 9% of the time but accounted for 34% of TN export over 11 mo. Excluding cattle from small wetlands is likely to have immediate water quality benefits.


Subject(s)
Cattle , Nitrogen/analysis , Water Quality , Wetlands , Animals , New Zealand
13.
Br J Anaesth ; 109(1): 21-6, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22696557

ABSTRACT

Teamwork involves supporting others, solving conflicts, exchanging information, and co-ordinating activities. This article describes the results of interviews with anaesthetic assistants (n=22) and consultant anaesthetists (n=11), investigating the non-technical skills involved in the effective teamwork of the anaesthetic assistants in the operating theatre. Anaesthetic assistants most commonly saw themselves as either being part of a theatre team or an anaesthetic subgroup and most commonly described the senior theatre nurse as their team leader. Examples of supporting others included the following: checking equipment, providing equipment, being a second pair of eyes, providing emotional and decision support, and supporting trainee anaesthetists. Of the 19 anaesthetic assistants who were asked if they would speak up if they disagreed with a decision in theatre, only 14 said that they would voice their concerns, and the most common approach was to ask for the logic behind the decision. The WHO checklist was described as prompting some anaesthetists to describe their anaesthetic plan to the anaesthetic assistant, when previously the anaesthetist would have failed to communicate their intentions in time for equipment to be prepared. The prioritization of activities to achieve co-ordination and the anaesthetic assistants becoming familiar with the idiosyncrasies of their regular anaesthetists were also described by anaesthetic assistants.


Subject(s)
Anesthesiology , Communication , Cooperative Behavior , Interprofessional Relations , Physician Assistants , Clinical Competence , Humans , Professional Role , Scotland
14.
Br J Anaesth ; 109(1): 27-31, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22581808

ABSTRACT

Non-technical skills (NTS), which include communication, teamwork, leadership, decision-making, and situation awareness, are important in the maintenance of patient safety. NTS frameworks have been developed for anaesthetists, surgeons, and scrub practitioners. Most studies of NTS in operating theatres to date have focused on anaesthetists and surgeons. We have attempted to identify the NTS used by anaesthetic assistants in the perioperative period. An electronic search of the NHS e-library, PubMed, BioMed Central, ScienceDirect, and Scopus databases was performed in December 2010. The abstracts of the papers identified were checked for relevance and the article examined. Out of 308 papers initially identified, there were only three papers describing the use of NTS by anaesthetic assistants. Communication and situation awareness were described in three papers, teamwork and decision-making in two, and leadership in one. This search did not reveal any comprehensive description of the NTS required by anaesthetic assistants. The benefits of developing an NTS taxonomy for anaesthetic assistants are discussed.


Subject(s)
Anesthesiology , Clinical Competence , Physician Assistants , Communication , Cooperative Behavior , Humans , Interprofessional Relations , Leadership , Perioperative Period
15.
Nurse Educ Pract ; 12(1): 46-51, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21684211

ABSTRACT

A shift in universities world wide in providing theoretical post graduate programmes of study underpinned by traditional assessment strategies to work based learning programmes supported by innovative assessment strategies is required if Higher education institutions are to effectively educate contemporary healthcare leaders. Concurrently generating the evidence to evaluate the effectiveness of educational programmes is required by commissioners of healthcare education (DH, 2010). This paper reports on the perceptions of twelve post graduate students attending a clinical leadership masters programme of their leadership development through analysis of the critical commentary provided by students as part of assessment strategy that utilised the Patchwork Text Assessment. Following a thematic content analysis six themes emerged: programme philosophy and its impact on the success of the Patchwork Text Assessment; leadership development targeted against leadership frameworks; application and applicability of learning to the students own healthcare organisation; integrating theory to practice through theoretical development and work based activities; the value of networking; and the importance of multi-professional reflective groups. This study has clearly demonstrated how the success of the Patchwork Text Assessment in promoting deep learning is determined by its integration into the overall philosophy of the programme. Concurrently systems needed to be in place to ensure that Patchwork text Assessment is operationalised effectively and embedded within the day to day management of the programme.


Subject(s)
Educational Measurement/methods , Health Personnel/education , Leadership , Professional Competence , Self-Assessment , Education, Graduate , England , Female , Health Personnel/psychology , Humans , Longitudinal Studies , Male , Program Evaluation , Social Support
17.
IEEE Pulse ; 1(1): 64-9, 2010.
Article in English | MEDLINE | ID: mdl-20875966

ABSTRACT

Welcome to the 21st century, where paradigms are shifting, roles are reversing, and changes in workflow influence-perhaps even dictate-new patterns of thought. If that sounds new age to you, then you might be onto something, because this is a new age, and new rules apply. We can no longer succeed by sitting atop a power hierarchy and bending others to our will; instead, we must step into the flow of others' work. This applies to every field, including biomedical engineering, where every inventor has a story about groundbreaking technology that never reached its target market. To what extent does changing our mindset for the 21st century influence the success of a device? To answer this question, we need to know the following: when useful technology, invented by the greatest minds in science, fails, what went wrong? And more importantly, when it succeeded-both from a medical and financial point of view-what went right, and how do we replicate that?


Subject(s)
Biomedical Engineering , Biomedical Technology , Industry/methods , Technology Transfer , Humans , Industry/economics , Industry/trends
19.
Clin Radiol ; 64(9): 857-71, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19664476

ABSTRACT

Malignancy presenting during pregnancy is rare. When it does, there are important considerations and challenges for the radiologist. The physiological changes of pregnancy may mask signs and symptoms of malignancy leading to delayed presentation. Endocrine and physiological changes during pregnancy can interact with tumour biology to alter the behaviour and patterns of growth of certain tumours. The timing and choice of imaging technique pose potential risks to the foetus, but this must be weighed against the risks to both mother and foetus of inadequate investigation or misdiagnosis. This review outlines the general principles and approach to imaging the pregnant patient with suspected malignancy, following which there is a more detailed discussion of the effects of pregnancy on tumour biology and presentation of specific tumours. Imaging strategies are discussed for the different entities, and where possible, evidence-based imaging recommendations are made.


Subject(s)
Diagnostic Imaging/methods , Neoplasms/diagnosis , Pregnancy Complications, Neoplastic/diagnosis , Adolescent , Adult , Biopsy , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/diagnosis , Carcinoma, Ductal, Breast/pathology , Central Nervous System Neoplasms/diagnosis , Central Nervous System Neoplasms/pathology , Contrast Media/adverse effects , Diagnosis, Differential , Diagnostic Errors , Diagnostic Imaging/adverse effects , Dose-Response Relationship, Radiation , Female , Gestational Trophoblastic Disease/diagnosis , Gestational Trophoblastic Disease/pathology , Glioma/diagnosis , Humans , Meningioma/diagnosis , Meningioma/pathology , Neoplasms/pathology , Pregnancy , Pregnancy Complications, Neoplastic/pathology , Prenatal Exposure Delayed Effects/epidemiology , Prenatal Exposure Delayed Effects/etiology , Young Adult
20.
Placenta ; 30(1): 105-10, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19038443

ABSTRACT

Fetal demand, shaped by factors such as number of fetuses, may alter placental regulation of exchange, even when maternal nutrition restriction is not overt. The marmoset is an interesting model in which to examine this aspect of placental function due to unique placentation that leads to multiple fetuses sharing a unified placental mass. We demonstrated previously that the triplet marmoset placenta exhibits significantly higher efficiency than does the twin placenta. Here, we test the hypothesis that this increased efficiency is due to increases in changes in the microscopic morphology of the placenta. Stereology was employed to analyze the microscopic architecture of placentas from twin and triplet pregnancies. Compartments of interest were the trabeculae, intertrabecular space, fetal capillaries, and the surface area of the maternal-fetal interface. Placentas from the two litters did not differ significantly in overall volume or individual volumetric compartments, but triplet placentas exhibited significant expansion of the trabecular surface area in comparison to twins (p=0.039). Further, the two groups differed in the isomorphy coefficient, with triplet placentas having a significantly higher coefficient (p=0.001) and potentially a more complex microscopic topography. Differences in the maternal-fetal interface may be due to developmental constraints on gross placental growth that occur earlier in gestation, such that the only option for maintaining sufficient access to maternal resources or signaling pathways late in gestation is via an expansion of the interface. Despite the significant increase in overall surface area, individual triplet fetuses are associated with much less surface area than are individual twins, suggestive of alterations in metabolic efficiency, perhaps via differential amino acid transport regulation.


Subject(s)
Callithrix/physiology , Fetal Development/physiology , Litter Size/physiology , Placenta/embryology , Prenatal Nutritional Physiological Phenomena/physiology , Animals , Female , Maternal-Fetal Exchange/physiology , Placenta/anatomy & histology , Placental Circulation/physiology , Pregnancy , Pregnancy, Multiple
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