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Despite recommendations to discontinue prophylactic antibiotics after incision closure or <24 hours after surgery, prophylactic antibiotics are continued after discharge by some clinicians. The objective of this study was to determine the prevalence and factors associated with postdischarge prophylactic antibiotic use after spinal fusion.
Multicenter retrospective cohort study.
This study included patients aged ≥18 years undergoing spinal fusion or refusion between July 2011 and June 2015 at 3 sites. Patients with an infection during the surgical admission were excluded.
Prophylactic antibiotics were identified at discharge. Factors associated with postdischarge prophylactic antibiotic use were identified using hierarchical generalized linear models.
In total, 8,652 spinal fusion admissions were included. Antibiotics were prescribed at discharge in 289 admissions (3.3%). The most commonly prescribed antibiotics were trimethoprim/sulfamethoxazole (22.1%), cephalexin (18.8%), and ciprofloxacin (17.1%). Adjusted for study site, significant factors associated with prophylactic discharge antibiotics included American Society of Anesthesiologists (ASA) class ≥3 (odds ratio [OR], 1.31; 95% CI, 1.00–1.70), lymphoma (OR, 2.57; 95% CI, 1.11–5.98), solid tumor (OR, 3.63; 95% CI, 1.62–8.14), morbid obesity (OR, 1.64; 95% CI, 1.09–2.47), paralysis (OR, 2.38; 95% CI, 1.30–4.37), hematoma/seroma (OR, 2.93; 95% CI, 1.17–7.33), thoracic surgery (OR, 1.39; 95% CI, 1.01–1.93), longer length of stay, and intraoperative antibiotics.
Postdischarge prophylactic antibiotics were uncommon after spinal fusion. Patient and perioperative factors were associated with continuation of prophylactic antibiotics after hospital discharge.
Introduction: Compared to other areas in Alberta Health Services (AHS), internal data show that emergency departments (EDs) and urgent care centres (UCCs) experience a high rate of workforce violence. As such, reducing violence in AHS EDs and UCCs is a key priority. This project explored staff's lived experience with patient violence with the goal of better understanding its impact, and what strategies and resources could be put in place. Methods: To obtain a representative sample, we recruited staff from EDs and a UCC (n = 6) situated in urban and rural settings across Alberta. As the interviews had the potential to be upsetting, we conducted in-person interviews in a private space. Interviews were conducted with over 60 staff members including RNs, LPNs, unit clerks, physicians, and protective services. Data collection and analysis occurred simultaneously and iteratively until saturation was reached. The analysis involved data reduction, category development, and synthesis. Key phrases and statements were first highlighted. Preliminary labels were then assigned to the data and data was then organized into meaningful clusters. Finally, we identified common themes of participants’ lived experience. Triangulation of sources, independent and team analysis, and frequent debriefing sessions were used to enhance the trustworthiness of the data. Results: Participants frequently noted the worry they carry with them when coming into work, but also said there was a high threshold of acceptance dominating ED culture. A recurring feature of this experience was the limited resources (e.g., no peace officers, scope of security staff) available to staff to respond when patients behave violently or are threatening. Education like non-violent crisis intervention training, although helpful, was insufficient to make staff feel safe. Participants voiced the need for more protective services, the addition of physical barriers like locking doors and glass partitions, more investment in addictions and mental health services (e.g., increased access to psychiatrists or addictions counsellors), and a greater shared understanding of AHS’ zero tolerance policy. Conclusion: ED and UCC staff describe being regularly exposed to violence from patients and visitors. Many of these incidents go unreported and unresolved, leaving the workforce feeling worried and unsupported. Beyond education, the ED and UCC workforce need additional resources to support them in feeling safe coming to work.
Introduction: Emergency Departments (EDs) are at high risk of workforce-directed violence (WDV). To address ED violence in Alberta Health Services (AHS), we conducted key informant interviews to identify successful strategies that could be adopted in AHS EDs. Methods: The project team identified potential participants through their ED network; additional contacts were identified through snowball sampling. We emailed 197 individuals from Alberta (123), Canada (46), and abroad (28). The interview guide was developed and reviewed in partnership with ED managers and Workplace Health and Safety. We conducted semi-structured phone interviews with 26 representatives from urban and rural EDs or similar settings from Canada, the United States, and Australia. This interview process received an ARECCI score of 2. Two researchers conducted a content analysis of the interview notes; rural and urban sites were analyzed separately. We extracted strategies, their impact, and implementation barriers and facilitators. Strategies identified were categorized into emergent themes. We aggregated similar strategies and highlighted key or unique findings. Results: Interview results showed that there is no single solution to address ED violence. Sites with effective violence prevention strategies used a comprehensive approach where multiple strategies were used to address the issue. For example, through a violence prevention working group, one site implemented weekly violence simulations, a peer mentorship support team, security rounding, and more. This multifaceted approach had positive results: a decrease in code whites, staff feeling more supported, and the site no longer being on union “concerned” lists. Another promising strategy included addressing the culture of violence by increasing reporting, clarifying policies (i.e., zero tolerance), and establishing flagging or alert systems for visitors with violent histories. Physician involvement and support was highly valued in responding to violence (e.g., support when refusing care, on the code white response team, flagging). Conclusion: Overall, one strategy is not enough to successfully address WDV in EDs. Strategies need to be comprehensive and context specific, especially when considering urban and rural sites with different resources available. We note that few strategies were formally evaluated, and recommend that future work focus on developing comprehensive metrics to evaluate the strategies and define success.
Adélie penguins (Pygoscelis adeliae) are responding to ocean–climate variability throughout the marine ecosystem of the western Antarctic Peninsula (WAP) where some breeding colonies have declined by 80%. Nuclear and mitochondrial DNA (mtDNA) markers were used to understand historical population genetic structure and gene flow given relatively recent and continuing reductions in sea ice habitats and changes in numbers of breeding adults at colonies throughout the WAP. Genetic diversity, spatial genetic structure, genetic signatures of fluctuations in population demography and gene flow were assessed in four regional Adélie penguin colonies. The analyses indicated little genetic structure overall based on bi-parentally inherited microsatellite markers (FST =-0.006–0.004). No significant variance was observed in overall haplotype frequency (mtDNA ΦST =0.017; P=0.112). Some comparisons with Charcot Island were significant, suggestive of female-biased philopatry. Estimates of gene flow based on a two-population coalescent model were asymmetrical from the species’ regional core to its northern range. Breeding Adélie penguins of the WAP are a panmictic population and hold adequate genetic diversity and dispersal capacity to be resilient to environmental change.
Introduction: Point of care ultrasound (PoCUS) has become an established tool in the initial management of patients with undifferentiated hypotension in the emergency department (ED). Current established protocols (e.g. RUSH and ACES) were developed by expert user opinion, rather than objective, prospective data. Recently the SHoC Protocol was published, recommending 3 core scans; cardiac, lung, and IVC; plus other scans when indicated clinically. We report the abnormal ultrasound findings from our international multicenter randomized controlled trial, to assess if the recommended 3 core SHoC protocol scans were chosen appropriately for this population. Methods: Recruitment occurred at seven centres in North America (4) and South Africa (3). Screening at triage identified patients (SBP<100 or shock index>1) who were randomized to PoCUS or control (standard care with no PoCUS) groups. All scans were performed by PoCUS-trained physicians within one hour of arrival in the ED. Demographics, clinical details and study findings were collected prospectively. A threshold incidence for positive findings of 10% was established as significant for the purposes of assessing the appropriateness of the core recommendations. Results: 138 patients had a PoCUS screen completed. All patients had cardiac, lung, IVC, aorta, abdominal, and pelvic scans. Reported abnormal findings included hyperdynamic LV function (59; 43%); small collapsing IVC (46; 33%); pericardial effusion (24; 17%); pleural fluid (19; 14%); hypodynamic LV function (15; 11%); large poorly collapsing IVC (13; 9%); peritoneal fluid (13; 9%); and aortic aneurysm (5; 4%). Conclusion: The 3 core SHoC Protocol recommendations included appropriate scans to detect all pathologies recorded at a rate of greater than 10 percent. The 3 most frequent findings were cardiac and IVC abnormalities, followed by lung. It is noted that peritoneal fluid was seen at a rate of 9%. Aortic aneurysms were rare. This data from the first RCT to compare PoCUS to standard care for undifferentiated hypotensive ED patients, supports the use of the prioritized SHoC protocol, though a larger study is required to confirm these findings.
Introduction: Point of care ultrasound (PoCUS) is an established tool in the initial management of patients with undifferentiated hypotension in the emergency department (ED). While PoCUS protocols have been shown to improve early diagnostic accuracy, there is little published evidence for any mortality benefit. We report the findings from our international multicenter randomized controlled trial, assessing the impact of a PoCUS protocol on survival and key clinical outcomes. Methods: Recruitment occurred at 7 centres in North America (4) and South Africa (3). Scans were performed by PoCUS-trained physicians. Screening at triage identified patients (SBP<100 or shock index>1), randomized to PoCUS or control (standard care and no PoCUS) groups. Demographics, clinical details and study findings were collected prospectively. Initial and secondary diagnoses were recorded at 0 and 60 minutes, with ultrasound performed in the PoCUS group prior to secondary assessment. The primary outcome measure was 30-day/discharge mortality. Secondary outcome measures included diagnostic accuracy, changes in vital signs, acid-base status, and length of stay. Categorical data was analyzed using Fishers test, and continuous data by Student T test and multi-level log-regression testing. (GraphPad/SPSS) Final chart review was blinded to initial impressions and PoCUS findings. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. There was no difference between groups for the primary outcome of mortality; PoCUS 32/129 (24.8%; 95% CI 14.3-35.3%) vs. Control 32/129 (24.8%; 95% CI 14.3-35.3%); RR 1.00 (95% CI 0.869 to 1.15; p=1.00). There were no differences in the secondary outcomes; ICU and total length of stay. Our sample size has a power of 0.80 (α:0.05) for a moderate effect size. Other secondary outcomes are reported separately. Conclusion: This is the first RCT to compare PoCUS to standard care for undifferentiated hypotensive ED patients. We did not find any mortality or length of stay benefits with the use of a PoCUS protocol, though a larger study is required to confirm these findings. While PoCUS may have diagnostic benefits, these may not translate into a survival benefit effect.
Introduction: Point of Care Ultrasound (PoCUS) protocols are commonly used to guide resuscitation for emergency department (ED) patients with undifferentiated non-traumatic hypotension. While PoCUS has been shown to improve early diagnosis, there is a minimal evidence for any outcome benefit. We completed an international multicenter randomized controlled trial (RCT) to assess the impact of a PoCUS protocol on key resuscitation markers in this group. We report diagnostic impact and mortality elsewhere. Methods: The SHoC-ED1 study compared the addition of PoCUS to standard care within the first hour in the treatment of adult patients presenting with undifferentiated hypotension (SBP<100 mmHg or a Shock Index >1.0) with a control group that did not receive PoCUS. Scans were performed by PoCUS-trained physicians. 4 North American, and 3 South African sites participated in the study. Resuscitation outcomes analyzed included volume of fluid administered in the ED, changes in shock index (SI), modified early warning score (MEWS), venous acid-base balance, and lactate, at one and four hours. Comparisons utilized a T-test as well as stratified binomial log-regression to assess for any significant improvement in resuscitation amount the outcomes. Our sample size was powered at 0.80 (α:0.05) for a moderate effect size. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. There was no significant difference in mean total volume of fluid received between the control (1658 ml; 95%CI 1365-1950) and PoCUS groups (1609 ml; 1385-1832; p=0.79). Significant improvements were seen in SI, MEWS, lactate and bicarbonate with resuscitation in both the PoCUS and control groups, however there was no difference between groups. Conclusion: SHOC-ED1 is the first RCT to compare PoCUS to standard of care in hypotensive ED patients. No significant difference in fluid used, or markers of resuscitation was found when comparing the use of a PoCUS protocol to that of standard of care in the resuscitation of patients with undifferentiated hypotension.
Introduction: Point of care ultrasonography (PoCUS) is an established tool in the initial management of hypotensive patients in the emergency department (ED). It has been shown rule out certain shock etiologies, and improve diagnostic certainty, however evidence on benefit in the management of hypotensive patients is limited. We report the findings from our international multicenter RCT assessing the impact of a PoCUS protocol on diagnostic accuracy, as well as other key outcomes including mortality, which are reported elsewhere. Methods: Recruitment occurred at 4 North American and 3 Southern African sites. Screening at triage identified patients (SBP<100 mmHg or shock index >1) who were randomized to either PoCUS or control groups. Scans were performed by PoCUS-trained physicians. Demographics, clinical details and findings were collected prospectively. Initial and secondary diagnoses were recorded at 0 and 60 minutes, with ultrasound performed in the PoCUS group prior to secondary assessment. Final chart review was blinded to initial impressions and PoCUS findings. Categorical data was analyzed using Fishers two-tailed test. Our sample size was powered at 0.80 (α:0.05) for a moderate effect size. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. The perceived shock category changed more frequently in the PoCUS group 20/127 (15.7%) vs. control 7/125 (5.6%); RR 2.81 (95% CI 1.23 to 6.42; p=0.0134). There was no significant difference in change of diagnostic impression between groups PoCUS 39/123 (31.7%) vs control 34/124 (27.4%); RR 1.16 (95% CI 0.786 to 1.70; p=0.4879). There was no significant difference in the rate of correct category of shock between PoCUS (118/127; 93%) and control (113/122; 93%); RR 1.00 (95% CI 0.936 to 1.08; p=1.00), or for correct diagnosis; PoCUS 90/127 (70%) vs control 86/122 (70%); RR 0.987 (95% CI 0.671 to 1.45; p=1.00). Conclusion: This is the first RCT to compare PoCUS to standard care for undifferentiated hypotensive ED patients. We found that the use of PoCUS did change physicians’ perceived shock category. PoCUS did not improve diagnostic accuracy for category of shock or diagnosis.
In the United States alone, ∼14,000 children are hospitalised annually with acute heart failure. The science and art of caring for these patients continues to evolve. The International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was held on February 4 and 5, 2015. The 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute was funded through the Andrews/Daicoff Cardiovascular Program Endowment, a philanthropic collaboration between All Children’s Hospital and the Morsani College of Medicine at the University of South Florida (USF). Sponsored by All Children’s Hospital Andrews/Daicoff Cardiovascular Program, the International Pediatric Heart Failure Summit assembled leaders in clinical and scientific disciplines related to paediatric heart failure and created a multi-disciplinary “think-tank”. The purpose of this manuscript is to summarise the lessons from the 2015 International Pediatric Heart Failure Summit of Johns Hopkins All Children’s Heart Institute, to describe the “state of the art” of the treatment of paediatric cardiac failure, and to discuss future directions for research in the domain of paediatric cardiac failure.
The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), outbreak in British Columbia and Alberta, Canada, currently extends over 18.3 million ha of pine forest. The principal host of the insect is lodgepole pine, Pinus contorta var. latifolia Englemann (Pineaceae) although it is a generalist herbivore on pines. Mountain pine beetles do not typically colonise spruce. However, during the current outbreak, several instances of mountain pine beetle attack on interior hybrid spruce, Picea glauca (Moench) Voss×Picea engelmannii Parry ex. Engelmann (Pinaceae) have been noted in areas where severe lodgepole pine mortality has occurred. Occasionally, beetle reproduction within spruce has been successful. Reproductive behaviours of mountain pine beetles reared from pine and spruce, such as female host acceptance and male joining behaviour, were studied on bolts of pine and spruce in laboratory bioassays. Females more readily accepted spruce host material relative to pine. Females that developed in spruce had higher rates of host acceptance of both pine and spruce host material than females that had developed in pine. We interpret these latter results with caution, however, as inference is partially restricted by sourcing viable insects from one spruce in this study. Implications of these findings to the concepts of host adaptation and population dynamics of this eruptive herbivore are discussed.
The success of central line-associated bloodstream infection (CLABSI) prevention programs in intensive care units (ICUs) has led to the expansion of surveillance at many hospitals. We sought to compare non-ICU CLABSI (nCLABSI) rates with national reports and describe methods of surveillance at several participating US institutions.
Design and Setting.
An electronic survey of several medical centers about infection surveillance practices and rate data for non-ICU Patients.
Ten tertiary care hospitals.
In March 2011, a survey was sent to 10 medical centers. The survey consisted of 12 questions regarding demographics and CLABSI surveillance methodology for non-ICU patients at each center. Participants were also asked to provide available rate and device utilization data.
Hospitals ranged in size from 238 to 1,400 total beds (median, 815). All hospitals reported using Centers for Disease Control and Prevention (CDC) definitions. Denominators were collected by different means: counting patients with central lines every day (5 hospitals), indirectly estimating on the basis of electronic orders (n = 4), or another automated method (n = 1). Rates of nCLABSI ranged from 0.2 to 4.2 infections per 1,000 catheter-days (median, 2.5). The national rate reported by the CDC using 2009 data from the National Healthcare Surveillance Network was 1.14 infections per 1,000 catheter-days.
Only 2 hospitals were below the pooled CLABSI rate for inpatient wards; all others exceeded this rate. Possible explanations include differences in average central line utilization or hospital size in the impact of certain clinical risk factors notably absent from the definition and in interpretation and reporting practices. Further investigation is necessary to determine whether the national benchmarks are low or whether the hospitals surveyed here represent a selection of outliers.
Automated surveillance using electronically available data has been found to be accurate and save time. An automated Clostridium difficile infection (CDI) surveillance algorithm was validated at 4 Centers for Disease Control and Prevention Epicenter hospitals. Electronic surveillance was highly sensitive, specific, and showed good to excellent agreement for hospital-onset; community-onset, study facility-associated; indeterminate; and recurrent CDI.
The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
To compare incidence of hospital-onset Clostridium difficile infection (CDI) measured by the use of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) discharge diagnosis codes with rates measured by the use of electronically available C. difficile toxin assay results.
Cases of hospital-onset CDI were identified at 5 US hospitals during the period from July 2000 through June 2006 with the use of 2 surveillance definitions: positive toxin assay results (gold standard) and secondary ICD-9-CM discharge diagnosis codes for CDI. The x2 test was used to compare incidence, linear regression models were used to analyze trends, and the test of equality was used to compare slopes.
Of 8,670 cases of hospital-onset CDI, 38% were identified by the use of both toxin assay results and the ICD-9-CM code, 16% by the use of toxin assay results alone, and 45% by the use of the ICD-9-CM code alone. Nearly half (47%) of cases of CDI identified by the use of a secondary diagnosis code alone were community-onset CDI according to the results of the toxin assay. The rate of hospital-onset CDI found by use of ICD-9-CM codes was significantly higher than the rate found by use of toxin assay results overall (P<.001), as well as individually at 3 of the 5 hospitals (P<.001 for all). The agreement between toxin assay results and the presence of a secondary ICD-9-CM diagnosis code for CDI was moderate, with an overall k value of 0.509 and hospital-specific k values of 0.489–0.570. Overall, the annual increase in CDI incidence was significantly greater for rates determined by the use of ICD-9-CM codes than for rates determined by the use of toxin assay results (P = .006).
Although the ICD-9-CM code for CDI seems to be adequate for measuring the overall CDI burden, use of the ICD-9-CM discharge diagnosis code for CDI, without present-on-admission code assignment, is not an acceptable surrogate for surveillance for hospital-onset CDI.
To evaluate the impact of cases of community-onset, healthcare facility (HCF)-associated Clostridium difficile infection (CDI) on the incidence and outbreak detection of CDI.
A retrospective multicenter cohort study.
Five university-affiliated, acute care HCFs in the United States.
We collected data (including results of C. difficile toxin assays of stool samples) on all of the adult patients admitted to the 5 hospitals during the period from July I, 2000, through June 30, 2006. CDI cases were classified as HCF-onset if they were diagnosed more than 48 hours after admission or as community-onset, HCF-associated if they were diagnosed within 48 hours after admission and if the patient had recently been discharged from the HCF. Four surveillance definitions were compared: cases of HCF-onset CDI only (hereafter referred to as HCF-onset CDI) and cases of HCF-onset and community-onset, HCF-associated CDI diagnosed within 30, 60, and 90 days after the last discharge from the study hospital (hereafter referred to as 30-day, 60-day, and 90-day CDI, respectively). Monthly CDI rates were compared. Control charts were used to identify potential CDI outbreaks.
The rate of 30-day CDI was significantly higher than the rate of HCF-onset CDI at 2 HCFs (P < .01 ). The rates of 30-day CDI were not statistically significantly different from the rates of 60-day or 90-day CDI at any HCF. The correlations between each HCF's monthly rates of HCF-onset CDI and 30-day CDI were almost perfect (ρ range, 0.94-0.99; P < .001). Overall, 12 time points had a CDI rate that was more than 3 standard deviations above the mean, including 11 time points identified using the definition for HCF-onset CDI and 9 time points identified using the definition for 30-day CDI, with discordant results at 4 time points (k = 0.794; P < .001).
Tracking cases of both community-onset and HCF-onset, HCF-associated CDI captures significantly more CDI cases, but surveillance of HCF-onset, HCF-associated CDI alone is sufficient to detect an outbreak.
Studies indicate that a student's career interest at medical school entry is related to his or her ultimate career. We sought to determine the level of interest in emergency medicine among students at the time of medical school entry, and to describe characteristics associated with students primarily interested in emergency medicine.
We surveyed students in 18 medical school classes from 8 Canadian universities between 2001 and 2004 at the commencement of their studies. Participants listed their top career choice and the degree to which a series of variables influenced their choices. We also collected demographic data.
Of 2420 surveys distributed, 2168 (89.6%) were completed. A total of 6.1% (95% confidence interval 5.1%–7.1%) of respondents cited emergency medicine as their first career choice. When compared with students primarily interested in family medicine, those primarily interested in emergency medicine reported a greater influence of hospital orientation and a lesser influence of social orientation on their career choice. When compared with students primarily interested in the surgical specialties, those primarily interested in emergency medicine were more likely to report medical lifestyle and varied scope of practice as important influences. When compared with students primarily interested in the medical specialties, those who reported interest in emergency medicine were more likely to report that a hospital orientation and varied scope of practice were important influences, and less likely to report that social orientation was important.
Students primarily interested in emergency medicine at medical school entry have attributes that differentiate them from students primarily interested in family medicine, the surgical specialties or the medical specialties. These findings may help guide future initiatives regarding emergency medicine education.
We consider how Antarctic seals may respond to changes in climate, realizing that
anthropogenic alteration of food webs will influence these responses. The
species considered include the ice-obligate - crabeater (Lobodon carcinophaga), Weddell (Leptonychotes weddellii), Ross (Ommataphoca rossii) and leopard (Hydrurga leptonyx) seal - and the ice-tolerant Antarctic fur
seal (Arctocephalus gazella) and southern
elephant seal (Mirounga leonina). The data
analysed are from long-term censuses of Weddell seals in McMurdo Sound
(1997–2006), and of Weddell, fur and elephant seals at Arthur
Harbour, Antarctic Peninsula (1974–2005). After considering their
responses to recent changes in environmental features, as well as projected and
current changes to their habitat our conclusions are that the distribution and
abundance of 1) crabeater and Weddell seals will be negatively affected by
changes in the extent, persistence and type of annual sea ice, 2) Ross and
leopard seal will be the least negatively influenced by changes in pack ice
characteristics, although, as may be the case for crabeater and Weddell,
population size and distribution may be altered through changes in food web
dynamics, and 3) southern elephant and fur seals will respond in ways opposite
to the pack ice species, but could also be influenced most immediately by
changes in their food resources due to factors other than climate.