Wednesday, November 22, 2017


Question Does the addition of home noninvasive ventilation to home oxygen therapy prolong time to readmission or death for patients with chronic obstructive pulmonary disease and persistent hypercapnia following a life-threatening exacerbation?

Findings In this randomized clinical trial of 116 patients, the addition of home noninvasive ventilation significantly prolonged time to readmission or death from 1.4 months to 4.3 months.

Meaning The addition of home noninvasive ventilation to home oxygen therapy may improve outcomes in patients with severe chronic obstructive pulmonary disease and persistent hypercapnia following hospital admission.

Tuesday, November 21, 2017

An attempted classification to encompass the diverse phenotypes of diabetes

The different forms of diabetes no longer lend them selves to two simple categories. Various efforts to refine the classification have been met with controversy and complicated by evolving understanding. Here is my attempt to summarize the current thinking.

Type 1: caused by complete autoimmune destruction of the beta cells. A good practical definition is that patients require exogenous insulin in order to stay alive. That is, they will invariably develop ketoacidosis (DKA) when deprived of insulin, even in the basal state. It is important to specify the basal state, because patients with other forms of diabetes can go into DKA as well, but only in the presence of some stressor such as sepsis, MI, stroke, etc. This designation has changed little in recent decades and remains useful, though it has seen some tweaks as noted below.

Type 1b aka 1.5: These designations are no longer very useful for a variety or reasons. They originally (especially 1b) referred to a group of patients in certain ethnic groups with phenotypic characteristics of both type 1 and type 2 diabetes who seemingly transitioned from type 1 to type 2 and/or back, due to a non autoimmune mechanism: intermittent reversible severe beta cell failure due to an exaggerated form of glucotoxicity. This group has subsequently been found to be more heterogeneous than previously thought, both in terms of ethnicity and pathogenesis. To confuse things further, these terms (especially 1.5) have also been used to denote late autoimmune diabetes of adulthood (LADA), an unrelated condition. The terms were partially replaced in popular usage with ketosis prone type 2 diabetes but that too has been waning in popularity, largely abandoned. The ADA, recognizing that there are patients who develop DKA but lack antibodies, created the category of “idiopathic type 1 diabetes.” A more recently proposed category recognizes the heterogeneity in these patients (and subclassifies them accordingly) and is known as ketosis prone diabetes (see below). To confuse things a bit, KPD also incorporates patients who do not fit this phenotype, in order to encompass all diabetic patients who go into ketoacidosis apart from some severe stress. (Note: a very early designation for patients seemingly transitioning between the phenotypes of DM 1 and 2 was Flatbush diabetes).

Ketosis prone diabetes (KPD): This is a proposed designation to replace the category immediately above and adds some other mechanisms, attempting to encompass all patients who spontaneously develop DKA. It recognizes the heterogeneity of the phenotype above, specifically the fact that some forms have an autoimmune pathogenesis. Its 4 categories are based on the presence or absence of beta cell reserve and the presence or absence of autoimmunity.

Type 2: DM 2 is pretty well defined and I will not spend a great deal of time here other than to caution against defining it as any case of diabetes that does not develop DKA in the basal state. That is to say that some forms of diabetes, that don’t invariably cause DKA in the basal state, are not appropriately classified as DM 2 as will be discussed below. Although DM 2 is itself heterogeneous the patients have in common insulin resistance, gradual beta cell fatigue and the metabolic syndrome.

Type 3: Here’s where it gets even more confusing. While often a wastebasket there are some forms of diabetes that rightfully belong in this category though in current literature they have varied and sometimes quite limited degrees of acceptance. There are numerous subcategories. Here they are.

Type 3, no letter designation: This is a theoretical construct that Alzheimer disease is essentially diabetes (insulin resistance) localized to the brain and might be effectively treated with insulin sensitizing agents.

Additional categories of DM 3, designated by letter, were taken from this site:

Type 3 A refers to genetic defects in beta cells, essentially MODY. Inheritance is monogenic autosomal dominant as opposed to the polygenic inheritance of DM 2.

Type 3 B refers to severe genetically determined insulin resistance as seen in Donohue syndrome and related disorders.

Type 3 C is a more accepted category and denotes diabetes due to damage to the pancreas as a whole, eg pancreatitis, pancreatic cancer or pancreatic trauma. [1] [2]. This is important because it is usually misdiagnosed as DM 2 yet has unique treatment implications.

Type 3 D is DM caused by other endocrinopathies eg Cushing’s.

Type 3 E refers to DM caused by drugs such as corticosteroids.

Type 3 F refers to DM caused by infection. In the cite referenced above congenital rubella was given as the example. Would Hep C fit in here?

Type 3 G refers to diabetes associated with unusual autoimmune diseases, eg stiff person syndrome.

Type 3 H refers to diabetes associated with Down’s syndrome.

Note: Although all the entities mentioned above under type 3 are real I could find little or no independent support in the literature for the nomenclature except for the one with no letter designation (Alzheimer disease) and type 3C.

Type 4 This is a theoretical construct based on an animal model, attempting to explain some instances of apparent DM 2 in lean adults. This may not be an important entity in man if it exists at all and might be confused with LADA.

Miscellaneous forms:

Latent autoimmune diabetes in adults (LADA). It is sometimes been referred to as DM 1.5.

Double diabetes. You could be unlucky and have both 1 & 2. Or, in DM 1, if you treat overeating with more and more and more insulin and thereby gain of sufficient weight the characteristics of DM 2 could develop secondarily.

Monday, November 20, 2017

Sunday, November 19, 2017

Saturday, November 18, 2017

Appropriate and inappropriate use of troponin assays

The article offers a useful perspective on troponin testing but, if I’m not mistaken (correct me if I’m wrong) starts out with an error:

Troponin is a protein in striated muscle that regulates excitation and contraction, and consists of 3 molecules: C, I, and T. Troponin I and T are specific to cardiac tissue…

I’m pretty sure skeletal muscle has troponin I and T.

At any rate, the key point of the article is that in the old days of the early generation troponins, any elevation meant the patient was having an acute MI, usually due to acute coronary syndrome. Several generations (and sensitivity improvements) later that is no longer the case. The problem is, too many of us apparently interpret troponins the way we did in those good old days. This, as the author points out, can lead to problems such as knee jerk anticoagulation.

The remedy for this, according to the author, is to do a history and physical before ordering a troponin. That’s easier said than done in the crazy environment of hospital medicine where time is of the essence and we often have to utilize a shotgun approach to very sick patients. The reality is that troponin positivity has now become much more complex and requires considerable skill in applying the result to the prevailing clinical context.

Friday, November 17, 2017

Antipyretic therapy in septic patients

Thursday, November 16, 2017

Your critically ill patient went into atrial fibrillation. Amiodarone was started. Now what?

Sound familiar? This paper makes the case for cardiology consultation, at least if the drug is going to be continued at discharge.

Wednesday, November 15, 2017

Monday, November 13, 2017

Atrial flutter

This review is mainly about the various mechanisms and electrocardiographic patterns.

Sunday, November 12, 2017

Fluid overload and sepsis and using bioimpedence to monitor it

Guideline-directed therapy for sepsis calls for early fluid resuscitation. Often patients receive large volumes of intravenous fluids. Bioimpedance vector analysis (BIVA) is a noninvasive technique useful for measuring total body water. In this prospective observational study, we enrolled 18 patients admitted to the intensive care unit for the treatment of sepsis syndromes. Laboratory data, clinical parameters, and BIVA were recorded daily. All but one patient experienced volume overload during the course of treatment. Two patients had greater than 20 L of excess volume. Volume overload is clinically represented by tissue edema. Edema is not a benign condition, as it impairs tissue oxygenation, obstructs capillary blood flow, disrupts metabolite clearance, and alters cell-to-cell interactions. Specifically, volume overload has been shown to impair pulmonary, cardiac, and renal function. A positive fluid balance is a predictor of hospital mortality. As septic patients recover, volume excess should be aggressively treated with the use of targeted diuretics and renal replacement therapies if necessary.

Saturday, November 11, 2017

EP testing in bradyarrhythmias

This free full text review deals mainly with the various mechanisms of AV block, clues on the surface ECG and when EP testing is needed.

Friday, November 10, 2017

Arrhythmogenic cardiomyopathy (aka arrhythmogenic right ventricular cardiomyopathy/dysplasia)

The new terminology relates to the increasing recognition of left ventricular involvement. Free full text review.

Thursday, November 09, 2017

Drug therapy to reduce AICD shocks

Wednesday, November 08, 2017

How to take a high yield history

Tuesday, November 07, 2017

High flow nasal canula: a game changer in respiratory medicine

Monday, November 06, 2017

Liberal versus restrictive transfusion strategy: the debate is not quite over

Although a hemoglobin of 7 has become a widely accepted threshold for transfusion in a variety of situations there remain areas of uncertainty. One of these areas is ischemic heart disease. The NIH sponsored MINT is being organized to address this question. (Public Citizen thinks it should not be carried out). One of the questions here is whether there is equipoise for such a trial. Public Citizen, while leveling their principal objections toward trial ethics and the informed consent process, implies that there is no equipoise and a higher hemoglobin threshold should be accepted. The argument that equipoise exists is based on the fact that for ischemic heart disease there are only low level data to guide transfusion practices. High level trials lumped patients together having many different underlying diseases. How might transfusion thresholds apply to various subgroups? That raises nearly endless questions.

What about, for example, oncology patients with septic shock? Check out the results of this single center RCT:

Objective: To assess whether a restrictive strategy of RBC transfusion reduces 28-day mortality when compared with a liberal strategy in cancer patients with septic shock.

Design: Single center, randomized, double-blind controlled trial.

Setting: Teaching hospital.

Patients: Adult cancer patients with septic shock in the first 6 hours of ICU admission.

Interventions: Patients were randomized to the liberal (hemoglobin threshold, less than 9 g/dL) or to the restrictive strategy (hemoglobin threshold, less than 7 g/dL) of RBC transfusion during ICU stay.

Measurements and Main Results: Patients were randomized to the liberal (n = 149) or to the restrictive transfusion strategy (n = 151) group. Patients in the liberal group received more RBC units than patients in the restrictive group (1 [0–3] vs 0 [0–2] unit; p less than 0.001). At 28 days after randomization, mortality rate in the liberal group (primary endpoint of the study) was 45% (67 patients) versus 56% (84 patients) in the restrictive group (hazard ratio, 0.74; 95% CI, 0.53–1.04; p = 0.08) with no differences in ICU and hospital length of stay. At 90 days after randomization, mortality rate in the liberal group was lower (59% vs 70%) than in the restrictive group (hazard ratio, 0.72; 95% CI, 0.53–0.97; p = 0.03).

Conclusions: We observed a survival trend favoring a liberal transfusion strategy in patients with septic shock when compared with the restrictive strategy. These results went in the opposite direction of the a priori hypothesis and of other trials in the field and need to be confirmed.

This contributes to the evidence we have to guide transfusion practices but also serves as a reminder that there is no pat answer. Clinical judgment must surpass slavish adherence to pathways and guidelines, which is what evidence based medicine is all about.

Sunday, November 05, 2017

Saturday, November 04, 2017

Thursday, November 02, 2017

Assessment of fluid responsiveness is associated with improvement in robust outcomes

The big question is how invasive you need to be to accomplish this.

Wednesday, November 01, 2017

Tuesday, October 31, 2017

COPD: another example of the epidemic of misdiagnosis


Guidelines recommend the confirmation of a COPD diagnosis with spirometry. International Classification of Diseases, Ninth Revision, Clinical Modification, diagnostic codes are frequently used to identify patients with COPD for administrative purposes. However, coding the diagnosis of COPD does not require confirmation using spirometry. The purpose of this study was to determine how often the discharge diagnosis of COPD is supported by spirometric measurements in the Veterans Affairs (VA) health system.


We reviewed records of patients hospitalized for COPD in a VA teaching hospital between 2005 and 2015. Individuals were counted once; rehospitalizations for COPD in the same time frame were excluded. Patient records were assessed for the presence of spirometric measurements and for spirometric evidence of COPD.


There were 1,278 discharges with the principal diagnosis of COPD and allied conditions in the time frame. A total of 826 discharged patients were included. Among them, 21% had no spirometric measurements, 12% were unable to perform the breathing maneuvers correctly, 56% had spirometric evidence of airways obstruction, and 11% had normal prebronchodilator or postbronchodilator FEV1/FVC measurements. Older patients were more likely to fail the spirometry test or have no documented spirometry. Younger patients were more likely to have the first spirometry conducted after their COPD hospitalizations.


Caution must be taken when using the discharge diagnosis database to measure health-care outcomes and determine resource management. Efforts are needed to assure that patients clinically suspected of having COPD are tested with spirometry to improve the accuracy of a COPD diagnosis.

Monday, October 30, 2017

Acute eosinophilic pneumonia

Sunday, October 29, 2017

Early head CT post cardiac arrest


Neurological emergencies can lead to cardiac arrest, and post-arrest patients can develop life-threatening neurological abnormalities. This study aims to estimate and characterize the use of early head CT (HCT), and its potential impact on post-resuscitation management.


This retrospective study analyzed 213 adults who suffered an out-of-hospital cardiac arrest (OHCA) and survived for at least 24 h. Demographics were collected and arrest-related variables were documented. Timing of HCT was recorded and if abnormalities were found on HCT within 24 h of resuscitation, any resulting changes in management were recorded. Outcome was measured by cerebral performance category at discharge.


Only 54% of patients who survived OHCA underwent HCT in the first 24 h after resuscitation. Patients who underwent HCT were healthier and had better pre-arrest functional status and shorter duration of arrest. Acute abnormalities were found on 38% of HCT and 34% of these abnormal scans resulted in management changes.


Early HCT is not consistently performed after OHCA and may be heavily influenced by a patient’s premorbid status and duration of arrest. Early HCT can demonstrate acute abnormalities that can result in significant changes in patient management.

Saturday, October 28, 2017

Friday, October 27, 2017


Thursday, October 26, 2017

What are the best agents for fever and neutropenia?


To compare the effectiveness and safety of antipseudomonal β-lactam empiric monotherapy for febrile neutropenia by network meta-analysis.


Searches using Pubmed, Cochrane CENTRAL, EMBASE and Web of Science Core Collection were carried out in June 2016. English articles, non-English articles, full-length articles, short articles and conference abstracts were allowed. Eligible trial design was a parallel-group individual randomization. We included febrile neutropenia adult and paediatric patients undergoing chemotherapy for either solid tumours or haematological malignancies and treated with intravenous antipseudomonal β-lactams for initial empiric therapy. Protocol was registered with PROSPERO ID 42016043377.


Of 1275 articles detected by the search, 50 studies with 10 872 patients were finally included. Among the guideline-recommended cefepime, meropenem, imipenem/cilastatin, piperacillin/tazobactam and ceftazidime; imipenem/cilastatin showed the highest odds of treatment success without modification, which was the primary endpoint, based on the random-effect model network analysis. Ceftazidime was related to lower treatment success rate without modification compared with imipenem/cilastatin with OR of 0.71 (95% CI 0.57–0.89, p 0.006). Imipenem/cilastatin showed the lowest odds of all-cause death. Patients treated with cefepime had higher risk for all-cause death compared with those treated with imipenem/cilastatin (OR 2.05, 95% CI 1.11–3.78, p 0.029). Any adverse event was significantly more prevalent in the imipenem/cilastatin arm; however, there was no difference concerning adverse events leading to discontinuation.


Imipenem/cilastatin, piperacillin/tazobactam and meropenem may be reasonable first-choice medications for empiric therapy of febrile neutropenia.

Wednesday, October 25, 2017

Diabetic striatopathy


•“Diabetic striatopathy” denotes a clinico-radiologic syndrome of chorea-ballism and striatal hyperintensities on MR imaging.
•It is common in elderly females with hyperglycemic hyperosmolar state but rare in diabetic ketoacidosis.
•Chorea-ballism usually resolves with intensive management of diabetic ketoacidosis.


“Diabetic striatopathy” is characterized by dyskinesias with basal ganglia hyperintensities on neuroimaging. It is usually reported in elderly females with hyperglycemic hyperosmolar state and rare in patients with diabetic ketoacidosis. Here, we report two young males with diabetic ketoacidosis presenting as striatopathy, along with review of literature.

Tuesday, October 24, 2017

Type 2 diabetes: it’s about more than “getting the numbers down”

We’ve known this for years now, so why are we still obsessed with it?

This article is spot on:

An important challenge in the management of patients with type 2 diabetes is cardiovascular disease (CVD) prevention. While it is well established that intensive glycemic control prevents the onset and slows the progression of certain microvascular complications, such a strategy utilized in multiple clinical trials over the past few decades has failed to show a similar benefit with regard to cardiovascular events, including mortality. Despite this, a major hope has been the discovery of glucose-lowering medications that simultaneously improve cardiovascular outcomes. Over the past year and a half, four randomized clinical trials (involving empagliflozin, pioglitazone, liraglutide, and semaglutide) have reported important benefits in preventing adverse cardiovascular outcomes in patients with or at risk for type 2 diabetes and established CVD. On the basis of these landmark trials, we propose that a paradigm shift in the management of patients with type 2 diabetes, specifically in those with prior macrovascular disease. A transition from current algorithms based primarily on hemoglobin A1c values to a more comprehensive strategy additionally focused on CVD prevention seems warranted.

Monday, October 23, 2017

SGLT2 inhibitors associated with no more DKA than other drugs in an insurance database


Overall, unadjusted DKA incidence were similar between SGLT2 and non-SGLT2 agents.

Overall, unadjusted DKA incidence dropped by ∼50% when excluding potential autoimmune diabetes.

Primary analysis found no statistically significant increased risk of DKA with SGLT2 inhibitors.

No increased risk of DKA with SGLT2 inhibitors when excluding potential autoimmune diabetes.

More than half of the DKA cases met the definition of potential autoimmune diabetes.



To estimate and compare incidence of diabetes ketoacidosis (DKA) among patients with type 2 diabetes who are newly treated with SGLT2 inhibitors (SGLT2i) versus non-SGLT2i antihyperglycemic agents (AHAs) in actual clinical practice.


A new-user cohort study design using a large insurance claims database in the US. DKA incidence was compared between new users of SGLT2i and new users of non-SGLT2i AHAs pair-matched on exposure propensity scores (EPS) using Cox regression models.


Overall, crude incidence rates (95% CI) per 1000 patient-years for DKA were 1.69 (1.22–2.30) and 1.83 (1.58–2.10) among new users of SGLT2i (n = 34,442) and non-SGLT2i AHAs (n = 126,703). These rates more than doubled among patients with prior insulin prescriptions but decreased by more than half in analyses that excluded potential autoimmune diabetes (PAD). The hazard ratio (95% CI) for DKA comparing new users of SGLT2i to new users of non-SGLT2i AHAs was 1.91 (0.94–4.11) (p = 0.09) among the 30,196 EPS-matched pairs overall, and 1.13 (0.43–3.00) (p = 0.81) among the 27,515 EPS-matched pairs that excluded PAD.


This was the first observational study that compared DKA risk between new users of SGLT2i and non-SGLT2i AHAs among patients with type 2 diabetes, and overall no statistically significant difference was detected.

Of note, although not statistically significant, there was a pretty strong signal toward more DKA with SGLT2i when a broader definition of DM 2 was used, which may have included some patients with previously undiagnosed autoimmune diabetes. For a stricter cohort of DM 2, patients with any prior history of insulin monotherapy and those under 40 were excluded.

Sunday, October 22, 2017

Saturday, October 21, 2017

Cardiac manifestations of neuromuscular diseases

An AHA scientific statement. Free full text.

Friday, October 20, 2017

Discontinuation of low dose aspirin leads to increased cardiovascular events

Results: During a median of 3.0 years of follow-up, 62 690 cardiovascular events occurred. Patients who discontinued aspirin had a higher rate of cardiovascular events than those who continued (multivariable-adjusted hazard ratio, 1.37; 95% confidence interval, 1.34–1.41), corresponding to an additional cardiovascular event observed per year in 1 of every 74 patients who discontinue aspirin. The risk increased shortly after discontinuation and did not appear to diminish over time.

Conclusions: In long-term users, discontinuation of low-dose aspirin in the absence of major surgery or bleeding was associated with a greater than 30% increased risk of cardiovascular events. Adherence to low-dose aspirin treatment in the absence of major surgery or bleeding is likely an important treatment goal.

These were people who were on it for either primary or secondary prevention.

Thursday, October 19, 2017

Atrioesophageal fistula after atrial fibrillation ablation

This is frightening. Fortunately, quite rare.

From the paper:

Esophageal perforation is a dreaded complication of atrial fibrillation ablation that occurs in 0.1% to 0.25% of atrial fibrillation ablation procedures. Delayed diagnosis is associated with the development of atrial-esophageal fistula (AEF) and increased mortality. The relationship between the esophagus and the left atrial posterior wall is variable, and the esophagus is most susceptible to injury where it is closest to areas of endocardial ablation. Esophageal ulcer seems to precede AEF development, and postablation endoscopy documenting esophageal ulcer may identify patients at higher risk for AEF. AEF has been reported with all modalities of atrial fibrillation ablation despite esophageal temperature monitoring. Despite the name AEF, fistulas functionally act 1 way, esophageal to atrial, which accounts for the observed symptoms and imaging findings. Because of the rarity of AEF, evaluation and validation of strategies to reduce AEF remain challenging. A high index of suspicion is recommended in patients who develop constitutional symptoms or sudden onset chest pain that start days or weeks after atrial fibrillation ablation. Early detection by computed tomography scan with oral and intravenous contrast is safe and feasible, whereas performance of esophageal endoscopy in the presence of AEF may result in significant neurological injury resulting from air embolism. Outcomes for esophageal stenting are poor in AEF. Aggressive intervention with skilled cardiac and thoracic surgeons may improve chances of stroke-free survival for all types of esophageal perforation.

Wednesday, October 18, 2017

Neurotoxicity of cefepime in relation to plasma concentration


In this single-centre retrospective cohort study, we enrolled all adult hospitalized patients receiving cefepime and undergoing TDM from January 2013 through July 2016. The primary outcome was the incidence of clinical toxicity; a secondary outcome was clinical failure. Plasma samples were analysed via high-performance liquid chromatography with ultraviolet detection.


A total of 161 cefepime concentrations were drawn from 93 patients. Roughly half (82/161, 51%) and one-third (49/161, 30%) were trough and steady-state levels from patients receiving intermittent and continuous infusions, respectively; median concentrations were 17.6 mg/L (IQR 9.7-35.2) and 29.2 mg/L (IQR 18.9-45.9). Ten patients (11%) experienced a neurologic event considered at least possibly related to cefepime; neurotoxicity was associated with poorer renal function (median creatinine clearance 54 (IQR 39-97) vs. 75 mL/min/1.732 (IQR 44-104)) and longer cefepime durations (mean 8.3 (SD±6.7) vs. 13.3 days (± 14.2), p = 0.071). Patients with trough levels greater than 20 mg/L had a fivefold higher risk for neurologic events (OR 5.05, 95% CI 1.3-19.8).


Neurotoxicity potentially related to cefepime occurred at plasma concentrations greater than 35 mg/L. For those receiving intermittent infusions, trough concentrations greater than 20 mg/L should be avoided until further information is available from prospective studies.

Tuesday, October 17, 2017

Which of the two popular regimens for community acquired pneumonia is best?


The best treatment option for hospitalized patients with community-acquired pneumonia (CAP) has not been defined. The effectiveness of β-lactam/fluoroquinolone (BLFQ) versus β-lactam/macrolide (BLM) combinations for the treatment of patients with CAP was evaluated.


PubMed, Scopus and the Cochrane Library were searched for observational cohort studies, non-randomized and randomized controlled trials providing data for patients with CAP receiving BLM or BLFQ. Mortality was the primary outcome. A meta-analysis was performed. MINORS and GRADE were used for data quality assessment.


Seventeen studies (16 684 patients) were included. Randomized trials were not identified. A variety of β-lactams, fluoroquinolones and macrolides were used within and between the studies. Mortality was reported at different time points. The available body of evidence had very low quality. In the analysis of unadjusted data, mortality with BLFQ was higher than with BLM (risk ratio 1.33, 95% CI 1.15–1.54, I2 28%). BLFQ was associated with higher mortality regardless of the study design, mortality recording time, study period and study BLM group mortality. BLFQ was associated with higher mortality in American but not European studies. No difference was observed in patients with bacteraemia and septic shock. In the meta-analysis of adjusted mortality data, a non-significant difference between the two regimens was observed (eight studies, adjusted risk ratio 1.26, 95% CI 0.95–1.67, I2 43%).


In the absence of data from randomized controlled trials recommendations cannot be made for or against either of the studied regimens in this group of hospitalized patients with CAP. Well designed randomized controlled trials comparing the two regimens are warranted.

Of interest, they didn’t compare fluoroquinolone monotherapy which is also popular and endorsed by CAP guidelines.

Monday, October 16, 2017

Sunday, October 15, 2017

The coming microbial apocalypse: Staph aureus in retreat?

Twenty years ago the post antibiotic era was predicted for gram positive infections. Five years or so later CA-MRSA began to overtake HA-MRSA. The takeover is complete, with the result that today’s MRSA, though resistant to most beta lactam antibiotics, is sensitive to several older antimicrobial agents besides vancomycin, in contrast to the older traditional MRSA (HA-MRSA). In a new development, a goodly number of MSSA  infections show susceptibility to plain penicillin.

Friday, October 13, 2017

Inappropriate IVC filter use continues apace

This is despite mounting evidence supporting restricted use as recommended in guidelines. This was the topic of several articles of interest in the May issue of Thrombosis Research.

Methods and results

We analyzed hospital discharge records of all patients with active cancer who were admitted to a California hospital specifically for acute DVT or PE between 2005 through 2009. Propensity and competing risk methodology were used to determine if IVCF-use lowered either 30-day mortality or the risk of recurrent PE, DVT, and major bleeding within 180 days. Among 14,000 patients, an IVCF was placed in 2747 (19.6%), but only 577 (21%) of these IVCF patients had an apparent indication for filter use because of acute bleeding or undergoing major surgery. Data on anticoagulation use was not available. Filter-use provided no reduction in either 30-day mortality (HR = 1.12, 95% CI: 0.99–1.26, p = 0.08) or the adjusted 180-day risk of subsequent PE (±DVT) (HR = 0.81, 95% CI: 0.52–1.27, p = 0.36). Filter use was, however, associated with an increase in the adjusted180-day risk of recurrent DVT (HR = 2.10, 95% CI: 1.53–2.89, p less than 0.0001).


We conclude that in this population-based study, approximately 20% of cancer patients with acute VTE received an IVCF, but only 21% of these had an indication for IVCF use. Overall, IVCF use provided neither a short-term survival benefit nor a reduction in risk of recurrent PE, but IVCF use was associated with a higher risk of recurrent DVT.


Inferior vena cava filters are used to prevent embolization of a lower extremity deep vein thrombosis when the risk of pulmonary embolism is thought to be high. However, evidence is lacking for their benefit and guidelines differ on the recommended indications for filter insertion. The study aim was to determine the reasons for inferior vena cava filter placement and subsequent complication rate.

Materials and methods

A retrospective cohort of patients receiving inferior vena cava filters in Edmonton, Alberta, Canada from 2007 to 2011. Main outcome was the indication of inferior vena cava filter insertion. Other measures include baseline demographic and medical history of patients, clinical outcomes and filter retrieval rates.


464 patients received inferior vena cava filters. An acute deep vein thrombosis with a contraindication to anticoagulation was the indication for 206 (44.4%) filter insertions. No contraindication to anticoagulation could be identified in 20.7% of filter placements. 30.6% were placed in those with active cancer, in which mortality was significantly higher. Only 38.9% of retrievable filters were successfully retrieved.


Inferior vena cava filters were placed frequently in patients with weak or no guideline-supported indications for filter placement and in up to 20% of patients with no contraindication to anticoagulation. The high rates of cancer and the high mortality rate of the cohort raise the possibility that some filters are placed inappropriately in end of life settings.

Here are a couple of related editorials: [1] [2]