Right Ventricular "Bubble Time" to Identify Patients With Right Ventricular Dysfunction

STUDY OBJECTIVE

We propose a novel method of evaluating right ventricular (RV) dysfunction in the emergency department (ED) using RV "bubble time"-the duration of time bubbles from a saline solution flush are visualized in the RV on echocardiography. The objective was to identify the optimal cutoff value for RV bubble time that differentiates patients with RV dysfunction and report on its diagnostic test characteristics.

METHODS

This prospective diagnostic accuracy study enrolled a convenience sample of hemodynamically stable patients in the ED. A sonographer administered a 10-mL saline solution flush into the patient's intravenous catheter, performed a bedside echocardiogram, and measured RV bubble time. Subsequently, the patient underwent a comprehensive cardiologist-interpreted echocardiogram within 36 hours, which served as the gold standard. Patients with RV strain or enlargement of the latter found on an echocardiogram were considered to have RV dysfunction. Bubble time was evaluated by a second provider, blinded to the initial results, who reviewed the ultrasound clips. The primary outcome measure was the optimal cutoff value of RV bubble time that identifies patients with and without RV dysfunction.

RESULTS

Of 196 patients, median age was 67 year, and half were women, with 69 (35.2%) having RV dysfunction. Median RV bubble time among patients with RV dysfunction was 62 seconds (interquartile range [IQR]: 52, 93) compared with 21 seconds (IQR: 12, 32) among patients without (P<.0001). The optimal cutoff value of RV bubble time for identifying patients with RV dysfunction was 40 or more seconds, with a sensitivity of 0.97 (95% CI 0.93 to 1.00) and specificity of 0.87 (95% CI 0.82 to 0.93).

CONCLUSION

In patients in the ED, an RV bubble time of 40 or more seconds had high sensitivity in identifying patients with RV dysfunction, whereas an RV bubble time of less than 40 seconds had good specificity in identifying patients without RV dysfunction. These findings warrant further investigation in undifferentiated patient populations and by emergency physicians without advanced ultrasound training.

Ultrasound Identification of Retrobulbar Hematomas by Emergency Physicians in a Cadaveric Model

INTRODUCTION

Retrobulbar hemorrhage (RBH) is a rare complication of facial trauma that can lead to dangerous orbital compartment pressures and must be rapidly recognized to prevent permanent vision loss. Point-of-care ultrasound (POCUS) offers a rapid modality for evaluating a wide variety of ocular pathologies, and prior case reports demonstrate the ability of clinicians to recognize RBH using ultrasound. This study aimed to assess the ability of clinicians at various stages of training to identify a RBH using POCUS in a cadaveric model. Clinicians also were assessed for self-reported comfort using ultrasound for ocular pathology before and after the study.

METHODS

Participants included 17 physicians who evaluated 10 eyes (from five cadavers) that were independently randomized to have either a modeled RBH or no hemorrhage. Participants' final diagnosis of each eye was recorded (RBH present or not), and participants also completed pre- and post-activity surveys.

RESULTS

The overall sensitivity and specificity to correctly diagnose retrobulbar fluid was 87% and 88%, respectively. Sensitivity and specificity were higher after excluding clinicians in their early phase of training. Additionally, self-reported comfort level with ocular ultrasound was significantly improved by this activity.

CONCLUSION

Emergency physicians at a variety of training levels can correctly identify a cadaveric model of retrobulbar hemorrhage. Use of this cadaveric model can improve exposure of clinicians to the appearance of a rare but vision-threatening ocular pathology such as RBH.

Gonococcal Tenosynovitis Diagnosed with the Aid of Emergency Department Bedside Ultrasound

BACKGROUND

Gonorrhea is the second most common sexually transmitted infection. Disseminated gonococcal infection (DGI) consists of gonococcal infection plus one or more of the triad of arthritis, tenosynovitis, and dermatitis. Diagnosis in the emergency department (ED) must be suspected clinically, as confirmatory tests are often not available. Point-of-care ultrasound (POCUS) can aid in diagnosis and appropriate management by identifying tenosynovitis and excluding arthritis.

CASE REPORT

A 26-year-old man with multiple recent sex partners presented to the ED with slowly progressing right wrist pain and swelling over 5 days. His dorsal right wrist was swollen, with slightly decreased range of motion owing to mild pain, and no warmth, tenderness, erythema, or drainage. Multiple hemorrhagic, gray-purple blisters were noted over both hands. Serum white blood cell count was 12 × 10³/μL; C-reactive protein was 30.3 mg/L. POCUS of the dorsal right wrist found no joint effusion; the extensor tendon sheath contained a large anechoic space with clear separation of the extensor tendons, suggesting a tendon sheath effusion/tenosynovitis. DGI was suspected, without septic arthritis. The patient was admitted and treated with ceftriaxone and azithromycin. Gonococcus grew from blood cultures and pharyngeal swabs. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: DGI must be suspected clinically, as confirmatory tests are often not available in the ED. Not all patients present with arthritis, tenosynovitis, and dermatitis. It is often difficult to differentiate tenosynovitis from arthritis. POCUS can aid in diagnosis by identifying tenosynovitis (vs. arthritis or simple soft-tissue swelling), allowing timely appropriate DGI diagnosis and management, and, importantly, averting unnecessary arthrocentesis.

Ultrasound-Guided Femoral Nerve Block to Facilitate the Closed Reduction of a Dislocated Hip Prosthesis

Prosthetic hip dislocation is a common but unfortunate complication in patients who have undergone total hip arthroplasty. Successful closed reduction in the emergency department leads to a reduced length of stay and rate of hospitalization.1,2 The use of regional anesthesia by femoral nerve block represents a novel approach for controlling pain in patients with hip pathologies.3 Ultrasound-guided approaches have been used with great success for controlling pain in patients with hip fractures.4,5 Here we report the case of a 90-year-old male who presented with a dislocated hip prosthesis, which was subsequently corrected with closed reduction following delivery of regional anesthesia to the femoral nerve under ultrasound guidance. To our knowledge, this represents the first reported use of an ultrasound-guided femoral nerve block to facilitate closed reduction of a dislocated prosthetic hip, and highlights a novel approach that avoids the use of procedural sedation in an elderly patient.

Prevalence and service implications of health anxiety in genitourinary medicine clinics

A comparison of the prevalence of health anxiety in genitourinary medicine (GUM) clinics in two UK centres was carried out using a new rating scale, the Health Anxiety Inventory (HAI). The relationship of health anxiety to demographic and clinical variables, and its impact on service contacts, was also examined in one of these centres. 694 patients were assessed and significant health anxiety was identified in 8–11%. HAI scores were stable over time and high levels persisted in the absence of treatment. Attenders with sexually transmitted infections had significantly lower levels of health anxiety than those with other conditions. Contacts with clinic doctors and health advisors in the nine months before and after assessment were significantly greater in those with high health anxiety, with doctor appointments 37% higher in the high HAI group ( P = 0.005). Health anxiety is a source of considerable morbidity in GUM clinics deserving further study.

The financial and service implications of splitting fixed-dose antiretroviral drugs - a case study

In 2010/2011, regional commissioners withdrew payment for the fixed-dose combination Combivir, forcing a switch to component drugs. This was deemed clinically acceptable and annual savings of £44 k expected. We estimated the true costs of switching and examined patient outcomes. Information for 46 patients using Combivir was extracted from case notes for each clinical contact in the 12 months pre- and post-switch (clinician seen, tests, antiretrovirals). Post-switch care costs £93/patient more annually versus pre-switch (95% CI £424 to £609), yielding £4278/year more post-switch for all patients. Drug and pathology costs were more expensive post-switch and extra clinical visits required. None of these results were statistically significant. Forty-two per cent of patients switched directly or in the subsequent year to an alternative fixed-dose combination rather than generics. Costs in this group were significantly higher post-switch driven by drug cost. Six patients (13%) reported problems with the switch including confusion around dosing and new side effects. As less-expensive generic antiretroviral drugs become available, it may appear cheaper to switch from fixed-dose combinations to component drugs. However, the additional clinical costs involved may outweigh the initial cost savings of the drugs and switching may cause confusion for some patients, risking loss of adherence.

Neuropilin2 regulates the guidance of post-crossing spinal commissural axons in a subtype-specific manner

BACKGROUND

Spinal commissural axons represent a model system for deciphering the molecular logic that regulates the guidance of midline-crossing axons in the developing central nervous system (CNS). Whether the same or specific sets of guidance signals control the navigation of molecularly distinct subtypes of these axons remains an open and largely unexplored question. Although it is well established that post-crossing commissural axons alter their responsiveness to midline-associated guidance cues, our understanding of the repulsive mechanisms that drive the post-crossing segments of these axons away from the midline and whether the underlying guidance systems operate in a commissural axon subtype-specific manner, remains fragmentary at best.

RESULTS

Here, we utilize axonally targeted transgenic reporter mice to visualize genetically distinct dorsal interneuron (dI)1 and dI4 commissural axons and show that the repulsive class 3 semaphorin (Sema3) guidance receptor Neuropilin 2 (Npn2), is selectively expressed on the dI1 population and is required for the guidance of post-crossing dI1, but not dI4, axons. Consistent with these observations, the midline-associated Npn2 ligands, Sema3F and Sema3B, promote the collapse of dI1, but not dI4, axon-associated growth cones in vitro. We also identify, for the first time, a discrete GABAergic population of ventral commissural neurons/axons in the embryonic mouse spinal cord that expresses Npn2, and show that Npn2 is required for the proper guidance of their post-crossing axons.

CONCLUSIONS

Together, our findings indicate that Npn2 is selectively expressed in distinct populations of commissural neurons in both the dorsal and ventral spinal cord, and suggest that Sema3-Npn2 signaling regulates the guidance of post-crossing commissural axons in a population-specific manner.

Health advisor workload

Health advisors (HAs) are an integral part of the multidisciplinary team within genitourinary (GU) medicine clinics, with a pivotal role in the National Sexual Health Strategy by enhancing liaison between community sexual health provision and GU medicine services. Greater clarity is needed about HAs' current activities and workload in order to enable benchmarking and ensure accurate workforce planning. We describe a tool for assessing HA workload and activity and evaluating its use in real clinic environments through a prospective time and motion model.

Ten centres (63% of those invited to participate) within a single region did so. Median HA working times were calculated at almost 15 min/patient consultation and approximately 10 min/telephone call.

Although there were strong positive correlations between HA availability and some markers of clinical activity, these were weaker than similar correlations applied to medical staff, raising the possibility of suboptimal HA workforce planning.

High prevalence of stress hyperglycaemia in children with febrile seizures and traumatic injuries

Although hyperglycaemia is relatively frequent in the course of severe illnesses and may be looked upon as the possible result of an uncoordinated insulin response to the increased glucose that the body may need during periods of stress, it is generally agreed that it does not constitute a prediabetic condition. Numerous studies have aimed to explain the pathophysiology of this occurrence but none has looked at which conditions are more prone to develop stress hyperglycaemia (SH). Therefore, the aim of this study was to evaluate the main clinical conditions that may be associated with SH in children. A total of 1199 children was studied: 833 children (439 M, 394 F, mean age 5.2 +/- 4.5 y) admitted for an acute illness or injury constituted the stress-exposed group, while 366 children (222 M, 144 F, mean age 6.2 +/- 4.6 y) admitted for elective minor surgery represented the stress-unexposed group and were considered as the control group. SH was defined as plasma glucose concentrations > or = 8.3 mmol l(-1) during an acute illness. Stress-exposed patients had significantly higher glycaemic levels than controls (5.6 +/- 1.4 vs 4.7 +/- 0.7 mmol l(-1); p < 0.0001). SH was found in 41 (4.9%) stress-exposed patients and in none of the controls. SH was significantly more prevalent in children affected by febrile seizures (12.9%) or traumatic injuries (11.7%; p < 0.008 and p < 0.02, respectively, vs other diagnoses). A significant correlation was found between glycaemia and systolic pressure (r = 0.1; p < 0.01), white cell count (r = 0.12; p < 0.0003) and body temperature (r = 0.16; p < 0.0001). SH was more frequent in patients with body temperature > 39 degrees C (14%) than in those with a temperature < or = 39 degrees C (4%; p < 0.0008). SH was more prevalent in clinical conditions of fever associated with seizures or pain (12.9% and 12.5%, respectively) than fever alone (4.4%). After a mean period of 3.5 +/- 0.6 y of follow-up none of the hyperglycaemic patients had developed diabetes mellitus.

CONCLUSION

Traumatic injuries, febrile seizures or conditions in which an elevated body temperature may be found are frequently associated with SH in children. In the presence of these conditions specific studies directed towards unmasking a prediabetic state may be unnecessary.

Virus-receptor interactions of human parainfluenza viruses types 1, 2 and 3

Human parainfluenza viruses types 1, 2 and 3 (HPF 1, 2 and 3) are important pathogens in children. While these viruses share common structures and replication strategies, they target different parts of the respiratory tract; the most common outcomes of infection with HPF3 are bronchiolitis and pneumonia, while HPF 1 and 2 are associated with croup. While the HPF3 fusion protein (F) is critical for membrane fusion, our previous work revealed that the receptor binding hemagglutinin-neuraminidase (HN) is also essential to the fusion process; interaction between HN and its sialic acid-containing receptor on cell surfaces is required for HPF3 mediated cell fusion. Using our understanding of HPF3 HN's functions in the cell-binding and viral entry process, we are investigating the ways in which these processes differ in HPF 1 and 2, in part by manipulating receptor availability. Three experimental treatments were used to compare the HN-receptor interaction of HPF 1, 2 and 3: infection at high multiplicity of infection (m.o.i.); bacterial neuraminidase treatment of cells infected at low m.o.i.; and viral neuraminidase treatment of cells infected at low m.o.i. (using Newcastle disease virus [NDV] neuraminidase or UV irradiated HPF3 as sources of neuraminidase). In cells infected with HPF3, we have shown that infection with high m.o.i. blocks fusion, by removing sialic acid receptors for the viral HN. However, in cells infected with HPF 1 and 2, infection with high m.o.i. did not block fusion; the fusion increases with increasing m.o.i. In cells infected with HPF 1 and 2, neither bacterial nor NDV neuraminidase blocked cell fusion, using amounts of neuraminidase that completely block fusion of HPF3 infected cells. However, when inactivated HPF3 was used as a source of viral neuraminidase, the treatment inhibited fusion of cells infected with HPF 1 and 2 as well as 3. The differences found between these viruses in terms of their interaction with the cell, ability to modulate cell-cell fusion and response to exogenous neuraminidases of various specificities, may reflect salient differences in biological properties of the three viruses.

A double-blind placebo-controlled phase II trial of thalidomide in asymptomatic HIV-positive patients: clinical tolerance and effect on activation markers and cytokines

A randomized double-blind, placebo-controlled study was performed to determine the safety, efficacy, and effect of thalidomide on a variety of immunological and biochemical parameters in asymptomatic human immunodeficiency virus (HIV)-positive patients. Nineteen male patients with elevated markers of immune activation and CD4 cell counts above 400/mm3 were randomized to either placebo or thalidomide at 100 mg/day for 24 weeks. However, only 3 (of 10) patients receiving thalidomide completed all 24 weeks compared to 6 (of 9) patients receiving placebo. This was mainly due to fatigue (somnolence is a recognized side effect), although this was also seen to a lesser extent in the placebo group and so may not be drug attributable. No significant changes in CD4/CD8 count, activation markers, TNF-alpha, or TNFR1 were observed. However, a nonsignificant trend toward inhibition of mitogen-induced TNF-alpha production was observed in the thalidomide arm. The lack of systemic effect and the lower tolerance of thalidomide (at this dose) in asymptomatic patients highlights the need for pharmacokinetic analysis to address possible absorption problems and the need for more potent and less toxic TNF-alpha inhibitors to be developed for use in this type of study.

Using continuous quality improvement tools to improve pediatric immunization rates

BACKGROUND

In August 1992 the medical director of the 19 Group Health medical clinics (now part of HealthPartners) in Minnesota chartered a continuous quality improvement (CQI) team to improve the pediatric (two-year-old) immunization rates. THE TEAM'S WORK: The team created a process flow for the current immunization process, collected data on the process, determined the causes of late or missed immunizations, collected data on children not up-to-date with immunization, analyzed the data, acted on recommendations, and obtained buy-in. The chief reasons for the child's not being up-to-date on immunizations included missed opportunities (when the child is in the clinic receiving care, perhaps for an acute illness, and could have safely received the immunization but did not), no previous visits or chart, and parents instructed to have their child return at two years.

INTERVENTION

Recommendations pertained to missed opportunities, record keeping, and enhanced patient and provider responsibility. For example, providers were given algorithms for catch-up of patients not on schedule or with incomplete immunizations. Another CQI team was launched to address and simplify the myriad locations in a medical record for recording information on immunizations. An automated vaccine administration record is now being piloted at two clinics.

RESULTS

Immunizations have increased from a mean of 53.5% before the team started to meet to a mean of 86.5% for the most recent four quarters for which data are available.

CONCLUSIONS

A problem is best addressed by the very people who will have to bring about the necessary changes for the desired improvements.

Elective lymph node dissection in stage I cutaneous malignant melanoma of the head and neck. A report from the Swedish Melanoma Study Group

The effect of elective lymph node dissection in patients with cutaneous malignant melanoma of the head and neck was investigated in a retrospective study. Of 517 patients in clinical stage I, 84 underwent elective dissection of the ipsilateral neck lymph nodes. In six of these patients, lymph node metastases were demonstrated at histopathological examination. There was a slight reduction in the incidence of recurrent disease in the regional lymph nodes in the group of patients who had undergone elective lymph node dissection, but this difference was not statistically significant. No significant differences were seen between the two groups regarding overall survival of disease-related survival.

Adverse effects of drugs used in the management of opportunistic infections associated with HIV infection

Pneumocystis carinii pneumonia (PCP) is one of the most common AIDS-defining diagnoses. First-line therapy is cotrimoxazole (trimethoprim-sulfamethoxazole), despite a high incidence of toxic effects, and a greater incidence of hypersensitivity reactions among HIV-positive patients compared with the seronegative population. Alternative agents such as intravenous pentamidine, or clindamycin with primaquine, and trimethoprim with dapsone, also have a wide range of serious adverse effects, but remain treatment options. Atovaquone appears promising for the treatment of both PCP and toxoplasmosis, and has a lower reported incidence of toxicity than the alternative agents. The most toxic antifungal drugs are reserved for serious infections, such as cryptococcal meningitis. Liposomal amphotericin B has less renal toxicity than standard formulations, and exemplifies that new formulations of existing drugs, although often expensive, may have a better adverse effect profile. There are 2 different drugs currently available for cytomegalovirus (CMV) infections, ganciclovir and foscarnet. Both have a high incidence of serious adverse effects; ganciclovir mainly causes bone marrow toxicity and foscarnet leads to renal toxicity. The drugs used for mycobacterial infection (including mycobacteria as well as tuberculosis) have a wide range of adverse effects, particularly skin rashes and drug-induced hepatitis. Some of these compounds are quite new, such as rifabutin and clarithromycin, and it is important to be ever vigilant for previously unreported adverse effects.

Cutaneous malignant melanoma of the head and neck. Analysis of treatment results and prognostic factors in 581 patients: a report from the Swedish Melanoma Study Group

BACKGROUND

Results of surgical treatment of cutaneous malignant melanoma (CMM) have been highly variable, probably because of patient selection. Therefore, a study of representative patients with this disease was performed.

METHODS

In a defined area of Sweden, 581 patients were analyzed. Clinical records and histopathologic findings were reviewed. The minimum follow-up time was 7 years. Prognostic factors were evaluated by the Cox proportional hazards model.

RESULTS

Evaluation of sex distribution, age, and anatomic site of the primary tumor showed that the patients were representative of all Swedish patients with CMM of the head and neck. The mean patient age at diagnosis was 64 years for both sexes. Fifty-three percent of the patients were women. Female patients had more tumors of the face than did male patients, whereas male patients were overrepresented among patients with tumors of the auricle-external ear canal and scalp-neck area. Localization to the face was observed in 68%, which is an overrepresentation of three to four times when skin surface is taken into consideration. Twenty-four percent of the patients had lentigo maligna melanoma. Only 33% of the patients had superficial spreading melanoma. In univariate analyses, sex, anatomic site of the primary tumor, histogenetic type, Clark level of invasion, and tumor thickness had prognostic power. In a multivariate analysis, tumor thickness, anatomic site of the primary tumor, and sex of the patient were independent prognostic factors.

CONCLUSIONS

In representative patients with CMM of the head and neck, tumor thickness, anatomic site of the primary tumor, and sex of the patients were independent prognostic factors.