Jon-Emile S. Kenny

Dr. Kenny is slowly curating the 'Finnegans Wake of Critical Care Blogs.' His favourite places are: Pier 64, The Hall of Ocean Life, Grand Central Station and the cafe at the top of Fotografiska. He has inherited his grandmother's fascination with the cosmos and Carl Sagan. Enjoy his homage to classical cardiorespiratory physiology at www.heart-lung.org

Feb 192018
 
The Great Lactate Debate Part 1: should we be counting protons or strong ions?

Jon-Emile S. Kenny MD [@heart_lung] “….  She was here on earth to grasp the meaning of its wild enchantment and to call each thing by its right name …” -Boris Pasternak Background Over the last half-decade, there has been a distinct shift in the approach to lactate elevation.  The long-held belief that elevated serum lactate [… read more]

Jan 312018
 
Choose Wisely – Avoid Sildenafil for Pulmonary Hypertension in Corrected Left-Heart Valvular Disease (SIOVAC Trial)

Jon-Emile S. Kenny MD [@heart_lung] “It’s these expressions, I never give, That keep me searching for a heart of gold … And I’m gettin’ old.” -Neil Young An 86 year old woman is admitted with progressive dyspnea and lower extremity edema.  8 months ago she received a trans-catheter aortic valve replacement (TAVR) for severe aortic [… read more]

Jan 292018
 
ICU Physiology in 1000 Words: Venous Doppler & Volume Tolerance

Jon-Emile S. Kenny MD [@heart_lung] With the birth of ‘fluid responsiveness’ physiology [1], there has been a slow and solemn drumbeat ushering the central venous pressure [CVP] up the squeaking planks of the hemodynamic gallows [2, 3].  Despite this, a few years ago I made a humble defense of the central venous pressure.  Importantly, I was [… read more]

Dec 262017
 
ICU Physiology in 1000 Words: Visualizing Heart-Lung Interaction

Jon-Emile S. Kenny MD [@heart_lung] “Upward, not northward.” -E. A. Abbott A pressure chamber within a pressure chamber; the heart within the thorax.  These are two pumps beating in-and-out of time, varying in physiology and pathophysiology between patients and within any one patient during the arc of an illness.  As such, when we inspect the [… read more]

Dec 182017
 
Esmolol in Sepsis: Microcirculatory Savior or Autoregulation Annihilator?

Jon-Emile S. Kenny MD [@heart_lung] Background If venous pressure were always the downstream pressure of an artery, then when flow is zero, the arterial pressure should equal the venous pressure.  For example, if one were to measure the coronary artery pressure and coronary sinus pressure at zero flow, their pressures should be equal.  Yet, this [… read more]

Dec 022017
 
A Great Lecture on Applied Respiratory Physiology

Jon-Emile S. Kenny MD [@heart_lung] -What is the world record for longest breath hold? -Why does the diagnosis of brain death require a rise in PaCO2 to at least 60 mmHg? -What minute ventilation can a human achieve? -What’s the difference between an elevated PaCO2 in someone who ‘won’t’ versus ‘can’t’ breathe? I’d like to [… read more]

Nov 262017
 
Sepsis, Diastolic Dysfunction & Hypernatremia

Jon-Emile S. Kenny MD [@heart_lung] with illustrations by Carla M Canepa MD “… And you may ask yourself … well, how did I get here? … And you may tell yourself … my God!  What have I done?” -David Byrne A 92 year old woman is transferred to the coronary care unit for treatment of pulmonary edema.  She [… read more]

Nov 112017
 
ICU Physiology in 1000 Words: Venous Excess & the Myth of Venous Return

Jon-Emile S. Kenny MD [@heart_lung] In the last few weeks I have been contacted by curious clinical physiologists craving my conceptions of ‘venous excess’ [1].  These words will address this model, concisely and – I pray – clearly. The Myth of Venous Return The roots of venous excess took hold within the fertile soil of [… read more]

Oct 192017
 
ICU Physiology in 1000 Words: Fighter Pilots!

Jon-Emile S. Kenny MD [@heart_lung] with illustrations by Carla M. Canepa MD Pilots of high-performance, tactical fighter jets each have continuous positive airway pressure [i.e. CPAP] masks as a part of their flight suit.  Strikingly, beyond the clinically-commonplace airway pressure of 5-15 cm of H2O, a fighter pilot may endure a mask-applied pressure of 90 [… read more]

Sep 292017
 
State-of-the-ART Trial: Do Recruitment Maneuvers & Higher PEEP Raise Mortality?

Jon-Emile S. Kenny MD [@heart_lung] “To believe in medicine would be the height of folly, if not to believe in it were not a greater folly still.” -Proust A 32 year old man with no past medical history save for a BMI of 51 is admitted with severe acute pancreatitis following a large intake of [… read more]

Sep 142017
 
ICU Physiology in 1000 Words: High Flow Oxygen Therapy

Jon-Emile S. Kenny MD [@heart_lung] That high flow oxygen applied via nasal cannula lends itself to treating hypoxemic respiratory failure may be obvious.  With adequate heat and humidification, oxygen can be employed relatively comfortably at very high flow rates – upwards of 60 L/min – to the nares.  At such rates, the effort of the [… read more]

Aug 302017
 
An Illustrated Guide to the Phases of ARDS: Implications for management

Jon-Emile S. Kenny MD [@heart_lung] with illustrations by Carla M. Canepa MD “Our life consists partly in madness, partly in wisdom: whoever writes about it merely respectfully and by rule leaves more than half of it behind.” -Montaigne Marking the 50 year anniversary of the first description of the adult respiratory distress syndrome – later [… read more]

Jul 292017
 
ICU Physiology in 1000 Words: IVC Collapse, Revisited – Part 2

Jon-Emile S. Kenny MD [@heart_lung] Please read part 1 and view the vodcast on inferior vena cava collapse prior to reading below; this post seeks to explain the interesting findings of Juhl-Olsen & colleagues [1] as well as provide a physiological rationale to Dr. Marik’s comments on my vodcast; there is a new explanatory animation [… read more]

Jul 222017
 
ICU Physiology in 1000 Words: IVC Collapse, Revisited – Part 1

Jon-Emile S. Kenny MD [@heart_lung] Three years ago I wanted to share my physiology website heart-lung.org; I needed a topic to stoke some interest, so I sent a brief essay to Matt here at pulmccm.org.  In it, I briefly described inspiratory IVC collapse and its relationship to volume status and volume responsiveness.  With this, the [… read more]

Jun 232017
 
ICU Physiology in 1000 Words: The Mean Systemic Filling Pressure – Part 2

Jon-Emile S. Kenny MD [@heart_lung] Briefly, part 1 of this reflection on the mean systemic filling pressure [Pmsf] considered an analogy for volume status as the vastness of an ocean beyond the hull of a leaking ship; I argue that looking only inside the hull of the ship cannot tell you the volume of the [… read more]

Jun 162017
 
ICU Physiology in 1000 Words: The Mean Systemic Filling Pressure – Part 1

Jon-Emile S. Kenny MD [@heart_lung] It’s 4 in the morning; I am somewhere between Riga and Stockholm.  The moon is full and bright and rippling across the black, Baltic Sea.  This warm, June darkness is cut like onyx by deep vibrations of a cruise ship and its collections of giggling Swedes; they karaoke ‘Spaceman’ by [… read more]

Apr 222017
 
ICU Physiology in 1000 Words: Weaning-Induced Cardiac Dysfunction & the Passive Leg Raise

Jon-Emile S. Kenny MD [@heart_lung] Reminder: Help me with my master’s thesis!  Please complete a learning module, and fill out this exceptionally brief survey! Perhaps the landmark trial elaborating an evolving cardiac dysfunction during the spontaneous breathing trial [SBT] is that of Lemaire and colleagues – published in 1988 [1].  One particularly memorable patient of [… read more]

Apr 062017
 
Free Online Hemodynamic Physiology Modules: an update & request

Jon-Emile S. Kenny MD [@heart_lung] “Oh, East is East and West is West, and never the twain shall meet …” -Kipling Last year, I began adding physiology modules to heart-lung.org as a part of a Master’s Degree I am undertaking at the Karolinska Institutet in Stockholm, Sweden.  The goal of these modules has been to encourage [… read more]

Mar 202017
 
ICU Physiology in 1000 Words: Heliox & Mechanical Power

Jon-Emile S. Kenny MD [@heart_lung] Of the countless things taught to me by Dr. Chitkara at the Palo Alto VA Health Care System, one that sticks is the difference between density-dependent and viscosity-dependent airflow.  He often used the chronic bronchitic suffering through the viscous, humid New York City summers as a teaching example.  The importance [… read more]

Feb 142017
 
A Primer on the Perils of Intravenous Fluids – Part 2

Jon-Emile S. Kenny [@heart_lung] Read part 1 here Fluids and the Glycocaylx Critically-ill patients all likely have endothelial dysfunction to some degree.  This perturbation in microvascular physiology may be underpinned by abnormal glycocalyx structure and function.  Sepsis, trauma, surgery and ischemic insults are all known to disrupt the glycocalyx which will increase vascular fluid capacitance.  [… read more]