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

Jun 182018
 
Driving Pressure in Airway Pressure Release Ventilation: a fool’s errand?

Jon-Emile S. Kenny MD [@heart_lung] “One of the symptoms of an approaching nervous breakdown is the belief that one’s work is terribly important.” -Bertrand Russel I read with great interest a recent letter penned by Taylor and Camporota in response to an investigation on airway pressure release ventilation [APRV] by Zhou and colleagues.  Their brief [… read more]

May 232018
 
A Free On-Line Hemodynamic Curriculum Grows

Jon-Emile S Kenny MD [@heart_lung] “What is memory but a story about how we have lived?” -Mark Doty During the recent ‘Hospitalist and the Resuscitationist’ conference in Montreal, there were discussions around the hemodynamics of prone positioning as well as using venous Doppler as a hemodynamic metric.  Much of this discussion was generated and driven [… read more]

May 162018
 
ICU Physiology in 1000 Words: Airway Pressure Release Ventilation – Part 3

Jon-Emile S. Kenny MD [@heart_lung] Lung Stress in Pulmonary & Extrapulmonary ARDS Initially described in the late 1990s, the distinction between direct pulmonary insults [i.e. pulmonary ARDS] and indirect pulmonary insults [i.e. extra-pulmonary ARDS] is important [1].  Additionally, direct pulmonary injury such as gastric acid aspiration may have a different molecular phenotype from indirect, extra-pulmonary [… read more]

May 152018
 
ICU Physiology in 1000 Words: Airway Pressure Release Ventilation – Part 2

Jon-Emile S. Kenny MD [@heart_lung] In the previous segment, time constants [t] – and their limitations – were described as a lesson in applied respiratory physiology for setting T-Low and prediction of auto-PEEP in airway pressure release ventilation [APRV].  In this brief missive an alternative approach to titrating T-low is described and critiqued.  As well, [… read more]

May 142018
 
ICU Physiology in 1000 Words: Airway Pressure Release Ventilation – Part 1

Jon-Emile S. Kenny MD [@heart_lung] While the lung in the throes of acute respiratory distress syndrome [ARDS] is shrunken, edematous and inflamed, a basic management maneuver is to ‘recruit’ lost pulmonary surface area.  In other words, unfold alveolar-capillary units with the ventilator like a respirothoracic party horn.  One ‘unconventional’ method of maximizing and maintaining lung [… read more]

Apr 232018
 
Lectures from the Inaugural 'Hospitalist and the Resuscitationist' Conference in Montreal, Canada

Jon-Emile S. Kenny MD [@heart_lung] “The real process of education should be the process of learning to think through the application of real problems.” -John Dewey On April 18 & 19, 2018, I had the pleasure of participating in the inaugural conference “The Hospitalist and the Resuscitationist” in Montreal.  The entirety of this meeting was [… read more]

Apr 042018
 
Are balanced crystalloids better than saline? SMART Talk with Dr. Michael Pinsky

Jon-Emile S. Kenny MD [@heart_lung] with illustrations by Carla M Canepa MD “Each time new experiments are observed to agree with the predictions, the theory survives and our confidence in it is increased; but if ever new observation is found to disagree, we have to abandon or modify the theory.” — Stephen Hawking A 47 [… read more]

Mar 242018
 
High-Flow Nasal Cannula, Work of Breathing & Mechanical Power: is there benefit?

Jon-Emile S. Kenny MD [@heart_lung] “I grow old … I grow old … I shall wear the bottoms of my trousers rolled.” -T. S. Eliot Background While it is tempting to isolate nasal high flow [NHF] into one’s cognitive schema for hypoxemia, NHF rightly deserves an esteemed position within one’s cerebral scaffolds for both hypercapnia [… read more]

Mar 122018
 
Is There Synergy between PEEP & Prone Position in ARDS?

Jon-Emile S. Kenny MD [@heart_lung] “… when you walk around a kitchen, you will say to yourself, this is interesting, this is grand, this is beautiful like Chardin.” -Marcel Proust Background Titration of positive end-expiratory pressure [PEEP] in the acute respiratory distress syndrome [ARDS] is achieved by a diverse assortment of practices undergirded by equally [… read more]

Feb 222018
 
The Great Lactate Debate Part 2: can we ‘myth-bust’ the strong ion approach?

Jon-Emile S. Kenny MD [@heart_lung] “The truth is rarely pure and never simple.” -Oscar Wilde In part 1, the crux of this ‘Great Lactate Debate’ was distilled into the unclear origin of the proton in the setting of ‘lactic acidosis.’  Is the [H+] secondary to biochemical work and ATP hydrolysis or is the proton from [… read more]

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]