Defibrillation probability and impedance change between shocks during resuscitation from out-of-hospital cardiac arrest

From Resuscitation via Science Direct:


Technical data now gathered by automated external defibrillators (AEDs) allows closer evaluation of the behavior of defibrillation shocks administered during out-of-hospital cardiac arrest. We analyzed technical data from a large case series to evaluate the change in transthoracic impedance between shocks, and to assess the heterogeneity of the probability of successful defibrillation across the population.


We analyzed a series of consecutive cases where AEDs delivered shocks to treat ventricular fibrillation (VF) during out-of-hospital cardiac arrest. Impedance measurements and VF termination efficacy were extracted from electronic records downloaded from biphasic AEDs deployed in three EMS systems. All patients received 200 J first shocks; second shocks were 200 J or 300 J, depending on local protocols. Results presented are median (25th, 75th percentiles).


Of 863 cases with defibrillation shocks, 467 contained multiple shocks because the first shock failed to terminate VF (n = 61) or VF recurred (n = 406). Defibrillation efficacy of subsequent shocks was significantly lower in patients that failed to defibrillate on first shock than in patients that did defibrillate on first shock (162/234 = 69% vs. 955/1027 = 93%; p < 0.0001). The failed VF terminations were distributed heterogeneously across the population; 5% of patients accounted for 71% of failed shocks. Shock impedance decreased by 1% [0%, 4%] and peak current increased by 1% [0%, 4%] between 200 J first and 200 J second shocks. Shock impedance decreased 4% [2%, 6%] and current increased 27% [25%, 29%] between 200 J first and 300 J second shocks. In all 499 pairs of same-energy consecutive shocks, impedance changed by less than 1% in 226 (45%), increased >1% in 124 (25%) and decreased >1% in 149 (30%).


Impedance change between consecutive shocks is minimal and inconsistent. Therefore, to increase current of a subsequent shock requires an increase of the energy setting. Distribution of failed shocks is far from random. First shock defibrillation failure is often predictive of low efficacy for subsequent shocks.

Court: State Budget Crisis Doesn’t Justify Pay Cut for Doctors

From the Wall Street Journal Health Blog:

Even if your state is so broke that it’s handing out IOUs instead of paying its bills, there’s a limit to how much you can cut payments to the doctors, dentists and other providers who are caring for the poor, a court ruled on Thursday. Here’s the story from the Los Angeles Times.

The backstory: Last year, as California was heading into its current financial crunch, the state legislature passed a law that would have cut by 10% reimbursements for treating patients covered by Medi-Cal. That’s the state’s version of Medicaid, the health insurance program for the poor, which is jointly funded by the state and federal governments.

Health-care providers sued to block the cuts last year, and a federal judge in Los Angeles ruled in their favor. A three-judge appeals panel yesterday upheld the ruling. The panel found that the cuts drove so many doctors and others to stop seeing Medi-Cal patients that patients’ ability to get care was jeopardized, violating a federal law that covers Medicaid funding to the states.

Nontraumatic Headaches in the Emergency Department: Evaluation of a Clinical Pathway

From Headche via Wiley Interscience:

Objective.—To determine the impact and efficacy of a clinical pathway in the management of patients with nontraumatic and afebrile headache (NTAH) in the emergency department (ED).

Background.—Nontraumatic and afebrile headache is one of the most common neurological symptoms in the ED. However, data about the application of an evidence-based operative protocol are lacking.

Methods.—A before–after intervention study comparing adult patients presenting to the ED with atraumatic headache was conducted during a 6-month period from April to September 2005 and with the same type of patients in the same period in 2006 after a clinical pathway had been implemented. According to their clinical presentations, patients of the 2006 group were divided into 3 subgroups and managed following the established protocol.

Study results were based on analysis of 6 months of clinical outcome, the number of CT head scans in the ED, number of neurological consultations in the ED, number of admissions, and length of stay in the ED.

Results.—A total of 686 patients were enrolled in the study, of which 374 were those presenting to our ED with NTAH in 2006 and managed with the aid of the study protocol; the other 312 patients were those who presented in 2005, before the intervention.

The study protocol was strictly applied to 247 patients (66%) of the 2006 group. There were fewer neurological consultations after the intervention (41.2% vs 52.5%, difference: −11.3%, 95% confidence intervals [CI]: −18.7% to −3.9%; P = .003); likewise, admissions were significantly reduced after the intervention (9.0% vs 14.7%, difference: −5.7%, 95% CI: −10.6% to −0.8%; P = .02). No significant differences were found between the 2 groups for number of CT head scans (42.2% vs 38.4%, difference: 3.7%, 95% CI: −3.5% to 11%; P = .3).

Mean length of stay in the ED was lower after the intervention, though not significantly (170.6 ± 102 minutes vs 180.5 ± 105 minutes, difference: −9.8 minutes, 95% CI: −20.3 to 5.7; P = .09). A 6-month follow-up was completed involving 302 (96.7%) patients in the first group and 370 (98.9%) in the second group. There was only one misdiagnosis after the intervention while 2 incorrect diagnoses were made before the intervention (0.27% vs 0.6%, difference: −0.33%, 95% CI: −2.1% to 0.9%; P = .5).

Conclusions.—Our diagnostic protocol for NTAH appears to be safe and sensitive in diagnosing malignant headaches. In addition, it may improve use of resources by reducing the need for neurological consultations and admissions without increasing the number of CT scans or prolonging length of stay in the ED. Furthermore, when using the protocol ED physicians seem more confident in their evaluations of headache resulting in fewer requests for specialist input.

Grassley Takes Closer Aim at Nonprofit Hospitals

From the Wall Street Journal Health Blog:

Sen. Chuck Grassley has a record of hammering nonprofit hospitals about whether they’re restricting care based on patients’ ability to pay and about how much care they provide for the uninsured in relation to the tax exemptions they enjoy.

Now Grassley, the top Republican on the Senate Finance Committee, and Chairman Max Baucus are trying to force change. They are considering provisions as part of the health-care overhaul that would target nonprofits’ tax breaks, which were designed to help those hospitals provide charity care, according to the WSJ.

Options include setting a minimum threshold of charity care that nonprofit hospitals must provide, limiting the amount they charge the uninsured and curbing instances of aggressive collection practices. Hospitals not meeting goals would be penalized with an excise tax, according to the ideas under consideration.

The scrutiny of nonprofits and their tax benefits has heightened amid the drive to overhaul health care. In theory at least, there should be less need for charity care if the number of uninsured Americans drops, as would be the goal if a revamped health system that requires universal coverage or something close to it.

Hemostasis in cardiac arrest patients treated with mild hypothermia initiated by cold fluids

From Resuscitation via Science Direct:

Aim of the study

Application of mild hypothermia (32–33 °C) has been shown to improve neurological outcome in patients with cardiac arrest. However, hypothermia affects hemostasis, and even mild hypothermia is associated with bleeding and increased transfusion requirements in surgery patients. On the other hand, crystalloid hemodilution has been shown to induce a hypercoagulable state. The study aim was to elucidate in which way the induction of mild therapeutic hypothermia by a bolus infusion of cold crystalloids affects the coagulation system of patients with cardiac arrest.


This was a prospective pilot study in 18 patients with cardiac arrest and return of spontaneous circulation (ROSC). Mild hypothermia was initiated by a bolus infusion of cold 0.9% saline fluid (4 °C; 30 ml/kg/30 min) and maintained for 24 h. At 0 h (before hypothermia), 1, 6 and 24 h we assessed coagulation parameters (PT, APPT), platelet count and performed thrombelastography (ROTEM) after in vitro addition of heparinase.


A total amount of 2528 (±528) ml of 0.9% saline fluid was given. Hematocrit (p < 0.01) and platelet count (−27%; p < 0.05) declined, whereas APTT increased (2.7-fold; p < 0.01) during the observation period. All ROTEM parameters besides clotting time (CT) after 1 h (−20%; p < 0.05) did not significantly change.


Mild hypothermia only slightly prolonged clotting time as measured by rotation thrombelastography. Therefore, therapeutic hypothermia initiated by cold crystalloid fluids has only minor overall effects on coagulation in patients with cardiac arrest.

Out-of-hospital cardiac arrest due to drowning: An Utstein Style report of 10 years of experience from St. Marys Hospital

From Resuscitation via Science Direct:


Drowning is a unique form of cardiac arrest and is often preventable. “Utstein Style for Drowning” was published in 2003 by the International Liaison Committee on Resuscitation (ILCOR) to improve the knowledge-base, to provide epidemiological stratification, to recommend appropriate treatments and to ultimately save lives. We report on the largest single-center study of the Utstein Style resuscitation for drowning.


All patients with out-of-hospital cardiac arrest (OHCA) due to drowning admitted to St. Mary’s Hospital between 1998 and 2007 were included. Utstein Style variables and other time intervals not included in the Utstein Style guidelines were evaluated for their ability to predict survival. The primary end point of this study was survival to discharge.


We enrolled 131 patients with OHCA due to drowning; 21 patients (16.03%) had survival to discharge and 9 patients (6.87%) were discharged with a good neurologic outcome, i.e., cerebral performance categories (CPC) of 1 or 2. For the Utstein Style variables witnessed, the duration of submersion and the time of first emergency medical systems (EMS) resuscitation attempt influenced survival. For other time intervals, the transportation time (i.e., time interval from witnessing of the drowning to EMS arrival at the hospital, or if events were not witnessed, the time interval from calling the EMS to EMS arrival at the hospital), the duration of advanced cardiovascular life support (ACLS) and the duration of total arrest time were associated with survival.


Our report is the largest single-center study of OHCA due to drowning reported according to the guidelines of the Utstein Style. Being witnessed, having a short duration of submersion, having early resuscitation by EMS, and rapid transportation are important for survival after drowning.

8 Common First Aid Mistakes And Myths That Make Things Worse

From HealthWatchCenter:

1. A child pulls a pot of boiling water off the stove or sticks their hand on a hot burner

Do you put butter or mayonnaise on the burn? Hurriedly remove the child’s clothing because it is stuck to the burn? Get out the ice?

Those are the common reactions in the case of a burn, but all of them are myths.

Butter, mayo or other types of grease may cause even more damage to tender skin and pulling clothing or other materials stuck to the burn could damage the tissue or pull the skin off completely.

The correct action is to rinse gently with cool water and coat the burn with antibiotic ointment. If the burn is on a sensitive area of the body such as the face or if there are a lot of blisters, then go to the ER and do not pop the blisters.

You also want to seek medical assistance if a burn completely circles a limb or is larger than your hand.