A hydrodynamic study of pleural drainage systems: some practical consequences

BACKGROUND: A pleural drainage system must be capable of efficiently evacuating the air or fluids from the pleural cavity so that adequate lung reexpansion can take place. The air flow and negative pressure of the system will depend on the particular design of each model. This experimental study analyzes the specifications and performance of the pleural drainage systems currently on the market. METHODS: Thirteen models of pleural drainage systems connected to wall suction were examined. The models were classified into the following three groups: dry systems; wet systems; and single-chamber systems. We determined the ambient air flow and the negative pressure generated according to the suction level. The components of each model are also described. RESULTS: Under normal conditions, dry (except for the Sentinel Seal; Sherwood Medical; Tullamore, Ireland), wet, and single-chamber systems reach similar air flow rates (17 to 30, 24 to 27, and 22 to 28 L/min, respectively). With higher wall suction levels, wet systems increase the air flow (26 to 49 L/min) but the negative pressure becomes unstable because of the water loss phenomenon, dry systems increase the air flow (29 to 50 L/min) without modifying the regulator pressure, and single-chamber systems also raise the air flow (45 to 51 L/min) but increase the negative pressure. When there is an air leak, dry systems (except for the Sentinel Seal) lose less negative pressure than the other systems. CONCLUSIONS: The functioning of these systems can be optimized only by applying a suitable wall suction level adjusted to each case. Although the three types of systems are capable of evacuating adequate air flow rates, the negative pressure and the capacity to maintain it in the presence of an air leak are different in each system. Being fitted with valves and not water compartments makes the dry systems the safest and the ideal for use when the patient has to be moved.     

Acquired pure red cell aplasia: a study of six cases

Persistent infection by parvovirus B19 associated with pure red cell aplasia (PRCA) has been documented in immunocompromised patients. Bone marrow failure is associated with conditions in which immune surveillance is impaired, and in these instances occult parvovirus infection may be suspected. In this study we have assessed by serological and molecular methods whether parvovirus B19 infection may be a more frequent cause of PRCA than hitherto suspected and whether it may be present in the absence of a typical bone marrow picture. Six patients with PRCA — two with isolated PRCA and no apparent underlying disease, two with a lymphoproliferative disease, one with thymoma, and one with chronic myelomonocytic leukemia — have been studied. Four of the six patients had overt PCRA and were clearly immunocompromised. Parvovirus B19 was not detected in any of the six patients by PCR analysis and serology investigating the presence of IgM or IgG antibodies. Although parvovirus B19 infection needs to be ruled out in PRCA it represents only one, and probably not the most frequent, etiological factor of PRCA.     

Healing of periodontal suprabony defects following treatment with open flap debridement with or without an enamel matrix derivative: A randomized controlled clinical study

Clinical Oral Investigations - To compare the healing of suprabony defects following treatment with either open flap debridement (OFD) and application of an enamel matrix derivative (EMD) with OFD...     

Understanding Athletic Trainers' Beliefs Toward a Multifacted Sport-Related Concussion Approach: Application of the Theory of Planned Behavior

Context:

Practice guidelines recommend a multifaceted approach for managing concussions, but a relatively small percentage of athletic trainers (ATs) follow these recommendations. Understanding ATs'' beliefs toward the recommended concussion practice guidelines is the first step in identifying interventions that could increase compliance. The theory of planned behavior (TPB) allows us to measure ATs'' beliefs toward the recommended concussion practice guidelines.

Objective:

To examine the influence of ATs'' beliefs toward the current recommended concussion guidelines on concussion-management practice through an application of the TPB.

Design:

Cross-sectional study.

Setting:

A Web link with a survey was e-mailed to 1000 randomly selected members of the National Athletic Trainers'' Association (NATA).

Patients or Other Participants:

A total of 221 certified ATs working in secondary school/clinic, high school, and college/university settings.

Main Outcome Measure(s):

A 66-item survey reflecting the current recommended concussion guidelines of the NATA and International Conference on Concussion in Sport was created to measure beliefs using the TPB constructs attitude toward the behavior (BA), subjective norms (SN), perceived behavioral control (PBC), and behavioral intention (BI) of ATs. We used a linear multiple regression to determine if the TPB constructs BA, SN, and PBC predicted BI and if PBC and BI predicted behavior according to the TPB model.

Results:

We found that BA, SN, and PBC predicted BI (R = 0.683, R² = 0.466, F_3,202 = 58.78, P < .001). The BA (t₂₀₂ = 5.53, P < .001) and PBC (t₂₀₂ = 9.64, P < .001) contributed to the model, whereas SN (t₂₀₂ = −0.84, P = .402) did not. The PBC and BI predicted behavior (R = 0.661, R² = 0.437, F_2,203 = 78.902, P < .001).

Conclusions:

In this sample, the TPB constructs predicted BI and behavior of ATs'' compliance with recommended concussion-management guidelines. The BA and PBC were the most influential constructs, indicating that those with positive attitudes toward concussion-management recommendations are more likely to implement them, and ATs are less likely to implement them when they do not believe they have the power to do so. We theorize that interventions targeting ATs'' attitudes and control perceptions will lead to improved compliance.Key Words: concussion management, traumatic brain injuries, practice guidelines

Key Points

• Using the theory of planned behavior constructs to investigate the application of recommended concussion-management guidelines by athletic trainers, we found that attitudes toward the behavior and perceived behavioral control were most influential.
• Interventions that take into account athletic trainers'' attitudes and perceived control may help to increase compliance with concussion-management guidelines.

Given estimates of 1.6 to 3.8 million sport-related concussions occurring in the United States each year,¹ sports medicine professionals must be able to evaluate and manage concussions properly. With most athletic injuries, the sports medicine team can clearly define the presence and severity of an injury; however, factors such as an athlete''s age² and sex³ and the location and magnitude of an impact⁴ can make it difficult to clearly define the severity of a concussion.To help sports medicine professionals who care for concussed athletes, a number of organizations^5–8 have proposed the use of a multifaceted approach to evaluate and manage sport-related concussions. The guidelines established by these organizations for the evaluation and management of sport-related concussions endorse the use of (1) a clinical examination,^5,7,8 (2) a symptom checklist,⁶ (3) postural-control assessment,^6–8 (4) neuropsychological testing,^5–8 (5) baseline testing when available for high–concussion-risk athletes,^6,7 and (6) a return-to-play protocol with a daily increase in activity once an athlete has been deemed symptom free.^5–8 Also, the recommendations emphasize that it is imperative to focus on the athlete''s data gathered from the evaluation when making a return-to-play (RTP) decision throughout the concussion-management process rather than relying on a predetermined timeline.^6–8The multifaceted approach to evaluating and managing concussions has been recommended since 2002.⁵ Sports medicine professionals have shown a steady but slow increase in compliance with the recommendations over the past decade, yet barriers to incorporation of these standards remain.^9–11 To improve compliance, it is important to understand sports medicine professionals'' beliefs about the multifaceted approach to concussion management.¹² If we can understand why a minority of sports medicine professionals use recommended concussion-management guidelines, we can identify strategies to change common practices. The theory of planned behavior (TPB) offers an avenue to investigate these beliefs.The TPB focuses on theoretical constructs that are concerned with individual motivational factors (behavioral intention [BI]) as determinants of the likelihood of performing a specific behavior.^13–15 The TPB includes measures of attitude, subjective normative perceptions, and perceived behavioral control (PBC) that determine BI, with BI leading to a behavior. The TPB assumes that all other factors, including demographics and the environment, operate through the model constructs and do not independently contribute to explaining the likelihood of performing a behavior.The TPB has 4 guiding constructs: (1) attitude toward the behavior (BA), or an individual''s positive or negative evaluation of self-performance of a behavior and an individual''s belief about the consequences of that behavior; (2) subjective norms (SN), or an individual''s perception of what other persons think about the individual performing the behavior and the individual''s motivation to comply; (3) PBC, or a perception that the individual has control over performing a behavior; and (4) BI, or the individual''s intent to perform or not perform the behavior based on the weight of the first 3 constructs (Figure 1). The TPB depicts behavior (B) as a linear regression function: B = w₁BI + w₂PBC, where w₁ and w₂ are empirically determined weights.Open in a separate windowFigure 1. Theory of planned behavior results with Pearson r (beta weight) for each construct. ^a Significant at P < .001.The following is an example of how the TPB can help us understand the decision-making process of a sports medicine professional in determining whether to use a concussion-management technique. An athletic trainer (AT) believes it is important to implement neuropsychological testing after every concussion (BA). The AT may or may not be influenced by his or her perceptions about how the head coach feels regarding this concussion-management tool (SN). Finally, the AT must decide if he or she has enough authority in the athletic department to acquire the funds to purchase the neuropsychological tests (PBC). According to the TPB, the summation of these 3 constructs results in the AT''s intention to perform neuropsychological tests. An AT who intends to perform neuropsychological tests is more likely to do so. However, if the AT feels that he or she lacks full volitional control over the behavior (PBC), the BI may have less influence on behavior.To understand why a minority of sports medicine professionals are currently applying the concussion-management guidelines, we would like to understand their beliefs and perceptions regarding the guidelines. Therefore, the purpose of our study was to examine the influence of ATs'' attitudes and beliefs toward the current recommended concussion-management guidelines through an application of the TPB.     

Pneumatic dilation for the treatment of achalasia in untreated patients and patients with failed Heller myotomy

BACKGROUND: Laparoscopic Heller myotomy (HM) has become an increasingly preferred modality to treat achalasia. However, the treatment course after a failed myotomy is controversial with fears that pneumatic dilation (PD) has high perforation risk. GOAL: To compare success and safety of graded PD with Rigiflex balloons in achalasia patients without a prior HM (untreated cases) and those with a failed HM. STUDY: A total of 108 patients were retrospectively evaluated: 96 untreated cases (53 male, 43 female, mean age 51 years) and 12 failed HM(7 male, 5 female, mean age 54 years). Symptoms (dysphagia and regurgitation) and physiologic studies, lower esophageal sphincter pressure (LESP) and timed barium swallow, assessed pre- and post-PD. Success was defined as: 1) symptom improvement to /=80% decrease in 5-minute barium column height from initial timed barium swallow. RESULTS: A total of 139 PDs performed (117 untreated cases, 22 failed HM): 2 perforations in untreated cases and none in failed HM group. Baseline demographics were similar, but failed HM patients had significantly lower LESP and timed barium swallow columns. Despite less LES resistance, failed HM group (symptom and physiologic success: 50% and 10%) did not do as well after PD as compared with untreated cases (symptom and physiologic success: 74% and 52%, respectively). Five failed HM patients had good symptom relief after PD compared with poor responders these patients were older (>50 years) and had LESP >17 mm Hg. CONCLUSIONS: PD perforation risk is not higher after HM. Despite lower LES pressure, patients undergoing PD after failed HM do not do as well as untreated cases. Factors predicting better outcome include older age and higher LES pressure.     

Circulating non-22 kDa growth hormone isoforms after a repeated GHRH stimulus in normal subjects.

The aim of this study was to evaluate the proportion of non-22 kDa GH isoforms in relation to total GH concentration after a repeated GHRH stimulus in healthy subjects. We studied 25 normal volunteers (12 males and 13 females, mean age 13.1 years, range 6-35), who received two GHRH bolus (1.5 mug/kg body weight, i.v.) administered separately by an interval of 120 minutes. The proportion of non-22 kDa GH was determined by the 22 kDa GH exclusion assay (GHEA), which is based on immunomagnetic extraction of monomeric and dimeric 22 kDa GH from serum, and quantitation of non-22 kDa GH isoforms using a polyclonal GH assay. Samples were collected at baseline and at 15-30 min intervals up to 240 min for total GH concentration. Non-22 kDa GH isoforms were measured in samples where peak GH after GHRH was observed. Total GH peaked after the first GHRH bolus in all subjects (median 37.2 ng/ml; range: 10.4-94.6). According to GH response to the second GHRH stimulus, the study group was divided in "non-responders" (n=7; 28%), with GH peak levels lower than 10 ng/ml (median GH: 8.7 ng/ml; range 7.3-9.6) and "responders" (n=18; 72%), who showed a GH response greater than 10 ng/ml (median 17 ng/ml; range 10.1-47.0). The median proportion of non-22 kDa GH on the peak of GH secretion after the first GHRH administration was similar in both groups ("responders" median: 8.6%, range 7-10.9%; "non-responders" median: 8.7%, range 6.7-10.3%), independently of the type of response after the second GHRH. In contrast, the median proportion of non-22 kDa GH was greater at time of GH peak after the second GHRH bolus in the "non-responders" (median 11.4%; range 9.1-14.3%) in comparison with the "responders" (median 9.1%; range 6.7-11.9%; p=0.003). A significant negative correlation between the total GH secreted and the percentage of non-22 kDa isoforms was seen in the "non-responders" (p=0.003). These differences in GH response to repeated GHRH stimulation and in the pattern of GH isoforms at GH peak among subjects might be due to distinct recovery patterns of somatrotrophic function and/or differences in metabolic clearance of GH isoforms.     

Rethinking Medicaid Coverage and Payment Policy to Promote High Value Care: The Case of Long-Acting Reversible Contraception

Context

Long-acting reversible contraception (LARC) is the most effective reversible method to prevent unplanned pregnancies. Variability in state-level policies and the high cost of LARC could create substantial inconsistencies in Medicaid coverage, despite federal guidance aimed at enhancing broad access. This study surveyed state Medicaid payment policies and outreach activities related to LARC to explore the scope of services covered.