Critical Care

Nov 302019
 
ICU Physiology in 1000 Words: Pulmonary Embolism & Right Ventricular Ischemia

Jon-Emile S. Kenny MD [@heart_lung] Commonly, we are sold that acute pulmonary thromboembolism [PE] burns the right ventricular [RV] candle at both ends.  This is because perfusion of the right coronary artery [RCA] is mediated by both its upstream mean arterial pressure [MAP] and downstream right ventricular end-diastolic pressure [RVEDP].  Given that a PE may decrease [… read more]

Nov 242019
 
ICU Physiology in 1000 Words: Pulmonary Embolism & Pulmonary Vascular Resistance

Jon-Emile S. Kenny MD [@heart_lung] What if I told you that in acute pulmonary thromboembolism [PE] that the initiation of intravenous norepinephrine [NE] decreases the calculated pulmonary vascular resistance [cPVR]?  Would you believe me?  Certainly, you would trust that an infusion of a thrombolytic does so.  Of great interest, both NE and thrombolytics decrease the cPVR [… read more]

Nov 172019
 
Vitamin E acetate in THC liquid is major cause of vaping lung injury, says CDC

The CDC has concluded that vitamin E acetate in vaping oils containing THC (tetrahydrocannabinol) is responsible for many cases of vaping-related lung injury. There have been over 2,051 confirmed and probable cases of e-cigarette or vaping-associated lung injury (EVALI), with 39 deaths. CDC made its advisement based on the consistent presence of vitamin E acetate [… read more]

Nov 112019
 
ICU Physiology in 1000 Words: Pulmonary Embolism & Syncope

Jon-Emile S. Kenny MD [@heart_lung] The transient and reversible loss of consciousness that may accompany pulmonary embolism [PE] is well-documented [1-7].  This brief post will not address the controversy regarding the prevalence of PE in ‘unexplained’ syncope; rather, it will focus on pathomechanisms and serve as the foundation for a few forthcoming entries on pulmonary thromboembolism [… read more]

Nov 072019
 
In sepsis, antibiotics reduced yield of blood cultures by almost 40%

by Molly Walker, Associate Editor, MedPage Today If you want an accurate reading from sepsis patients’ blood cultures, don’t start antibiotics until you’ve drawn the blood samples, a new study suggested. Among patients with severe sepsis, blood cultures taken prior to antibiotic therapy were positive for one or more microbial pathogens in 31.4% of patients [… read more]

Oct 312019
 
Vitamin C reduces mortality from sepsis with ARDS in CITRIS-ALI randomized trial ... ?

Vitamin C infusion has generated tremendous interest as an adjunctive treatment for patients with sepsis, since a widely publicized cohort study claimed vitamin C dramatically reduced sepsis-related mortality at a single institution. The publicity, the plausible pathophysiologic mechanism, and the lack of any therapy for sepsis have led many intensivists to prescribe the so-called Marik [… read more]

Oct 302019
 
Vaping-Associated Lung Injury – Part 2

Jon-Emile S. Kenny MD [@heart_lung] “There are sadistic scientists who hurry to hunt down errors instead of establishing the truth.” -Marie Curie In part 1 of Vaping-Associated Lung Injury, the very basics of electronic nicotine delivery systems [ENDS] were covered as well as highlights on clinical presentation, radiology and pathology.  In this second part, flurries of [… read more]

Oct 292019
 
Vaping-Associated Lung Injury – Part 1

Jon-Emile S. Kenny MD [@heart_lung] with illustration by Carla M. Canepa MD [@_carlemd_] “Inside the word ‘emergency’ is ‘emerge’; from an emergency, new things come forth.” -Rebecca Solnit Case A 32-year-old man is admitted with three days of fevers, chills, malaise, dyspnea and productive cough.  He works in a stressful job in the heart of Manhattan [… read more]

Oct 182019
 
Prolonged hypothermia improved neurologic outcomes after non-shockable cardiac arrests (HYPERION, CRICS-TRIGGERSEP)

Targeted temperature management (TTM, or therapeutic hypothermia) has become standard therapy after cardiac arrest, especially for ventricular tachycardia and fibrillation–so called shockable rhythms. A new randomized trial has shown that deep, prolonged cooling after cardiac arrest from non-shockable rhythms (PEA and asystole) improved neurologic outcomes. But how robust were the results, and should they change [… read more]

Sep 062019
 
Prophylactic IVC filters prevent PE in high-risk trauma patients, but were often unnecessary

Inferior vena cava filters placed prophylactically in patients hospitalized for trauma prevented symptomatic pulmonary embolism in those patients with persistent contraindications to anticoagulation, in a significant randomized trial. However, prophylactic IVC filter placement for all post-trauma patients did not improve outcomes generally. Trauma teams have always faced a difficult dilemma in the prevention and treatment [… read more]

Sep 032019
 
Advisory from CDC re: Severe Pulmonary Disease Associated with Using E-Cigarette Products

From the Centers for Disease Control and Prevention (CDC) and distributed here in the interest of the public health. PulmCCM is not affiliated with the CDC. Distributed via the CDC Health Alert Network August 30, 2019, 0935 AM ET (9:35 AM ET) CDCHAN-00421 The Centers for Disease Control and Prevention (CDC) is providing: 1) background [… read more]

Aug 232019
 
APRV and Esophageal Manometry: a new way to titrate T-Low?

Jon-Emile S. Kenny MD [@heart_lung] “I had some dreams, they were clouds in my coffee, clouds in my coffee …” -Carly Simon Background  A recent letter to the editor in Critical Care posed a rather provocative question – ‘Are we really preventing lung collapse with APRV?’  The authors cited a case report of esophageal manometry used in [… read more]

Jul 182019
 
ICU Physiology in 1000 Words: Venous Doppler & Veno-Cardiac Coupling – Part 2

Jon-Emile S. Kenny MD [@heart_lung] In part 1, the basics of ventriculo-arterial coupling [VAC] were described and related to the Guyton Diagram.  In this second part, the notion of cardiac performance [Eh] is explored in relation to venous Doppler velocimetry.  Subsequently, I hypothesize that ‘veno-cardiac uncoupling’ – a concept analogous to VAC – is a [… read more]

Jul 172019
 
ICU Physiology in 1000 Words: Venous Doppler & Veno-Cardiac Coupling – Part 1

Jon-Emile S. Kenny MD [@heart_lung] Background Concepts have been clanging around my head since I participated in Philippe Rola’s [@thinkingCC] sedulous Hospitalist & Resuscitationist Conference in Montreal.  Initially, the abstractions of ventriculo-arterial coupling, Guytonian physiology and venous Doppler seemed insuperably sundered; but the cognitive haranguing recently gave way to harmony. What is ventriculo-arterial coupling and [… read more]

Jun 302019
 
Intravenous Fluids Act as Inotropes in Recent Sepsis Study

Jon-Emile S. Kenny MD [@heart_lung] “I’ve looked at clouds from both sides now …” -Joni Mitchell Background In a recent physiological study – brought to my attention by the erudite and kinetic [@iceman_ex] – the detailed physiological effects of intravenous fluids, norepinephrine and dobutamine were sequentially evaluated in patients with sepsis.  Sepsis was defined as [… read more]

Jun 092019
 
Dexmedetomidine helpful but inadequate alone for sedation (SPICE III)

In a new randomized trial, use of dexmedetomidine (Precedex) as the primary sedative in mechanically ventilated patients in the ICU resulted in no reduction in 90 day mortality. Dexmedetomidine resulted in a small improvement in delirium and ventilator days, but was almost never adequate to sedate patients on its own, and brought a small increase [… read more]

May 302019
 
Neuromuscular blockade for ARDS was no help, in supine patients

Continuous neuromuscular blockade for severe ARDS became common practice after the ACURASYS trial (2010) showed it reduced mortality by an absolute 9%. A larger trial, ROSE, now finds no benefit of the therapy over usual care — but leaves lingering questions due to major design differences. The ROSE trial was a multicenter randomized trial in [… read more]

May 282019
 
Pitfalls when using Doppler Ultrasound to Measure Peripheral Flow: A Lecture from the Hospitalist & Resuscitationist Conference

Jon-Emile S. Kenny MD [@heart_lung] “I am fearful, or suspicious of generalizations … they cannot guide me reliably in making decisions about particular individuals.” -Ruth Bader Ginsburg Between the 22nd and 24th of May, I participated in the “Hospitalist and the Resuscitationist” conference in Montreal, Canada.  I spoke on the stanchions of physiology and evidence [… read more]

May 272019
 
Integrating the Evidence and Physiology of IVC Collapse: A Lecture from the Hospitalist & Resuscitationist Conference in Montreal

Jon-Emile S. Kenny MD [@heart_lung] “There is no power for change greater than a community discovering what it cares about.” -Margaret J. Wheatley Between the 22nd and 24th of May, I participated in the galvanic, second-annual “Hospitalist and the Resuscitationist” conference in Montreal, Canada.  The entirety of this meeting was organized by Dr. Philippe Rola [… read more]

Apr 292019
 
ICU Physiology in 1000 Words: The Respiratory System Pressure-Volume Curve

Jon-Emile S. Kenny MD [@heart_lung] More than 20 years ago Amato and colleagues reported a significant mortality reduction in ARDS patients who had their ventilator settings guided by the pressure-volume [PV] curve [1].  The 28-day mortality reduction was profound – 71% versus 38% – in favour of the patients who had their positive end-expiratory pressure [… read more]