Rob Graham - Academia.edu (original) (raw)

Papers by Rob Graham

Neonatology Today, 2021

Ever since mechanical ventilators were first used on babies nearly 60 years ago, the consequences... more Ever since mechanical ventilators were first used on babies nearly 60 years ago, the consequences of positive pressure ventilation (PPV) have been apparent. Despite many advancements in the technology behind mechanical ventilators, normal breathing involves negative pressure, and PPV is fundamentally unnatural. Despite the best of intentions and use of lung-protective ventilation strategies, PPV too often results in abnormal pulmonary development with attending long-term sequelae. While the whole may be greater than the sum of its parts, the failure of one of those parts makes that part the most valuable of all. This is never more so than when the lungs fail. The failure of lungs before they have fully developed presents a veritable quagmire akin to a whack-a-mole game from hell; the fix for one problem creates or is the opposite fix for another. Pulmonary development is at its infancy (no pun intended) in the sub-25-week post-conceptual age (PCA) baby, and barely able to sustain life, let alone growth at 22 weeks PCA. Be that as it may, Dr. Jonathan Klein of Iowa has shown us that with extreme skill, these infants can and do survive and grow, albeit after a long, costly course in the hospital. Even with the best of care, much of the NICU stay is spent recovering from our efforts to keep them alive.

Neonatology Today, 2021

We are accustomed to referring to the first hour of a baby's life as "the golden hour." If the fi... more We are accustomed to referring to the first hour of a baby's life as "the golden hour." If the first hour is golden, then the first ten minutes of that hour are platinum.

Neonatology Today, 2021

In June's Neonatology Today column we discussed "just right" values relating to PaCO 2. This mont... more In June's Neonatology Today column we discussed "just right" values relating to PaCO 2. This month's focus is on oxygen. In utero development occurs in a relatively hypoxic environment with PaO 2 of approximately 20 mmHg, (1) thus even room air represents a hyperoxic environment to the newborn infant. To protect the infant from hyperoxia and resulting formation of reactive oxygen species (ROS) (free radicals), just prior to term gestation non-enzymatic antioxidants (i.e. glutathione, vitamins C and E, and carotenoids) cross the placenta and endogenous antioxidant systems are up-regulated immediately prior to birth and are further up-regulated upon exposure to room air. Glutathione (GSH) is by far the most abundant antioxidant in the human body, and premature infants have low levels of GSH. (2)

Neonatology Today, 2021

Despite being used routinely for over 30 years, controversies remain regarding the method of admi... more Despite being used routinely for over 30 years, controversies remain regarding the method of administration and surfactant formulations themselves. Adverse events such as spontaneous airway obstruction, pneumothorax, pulmonary hemorrhage, changes in cerebral perfusion, bradycardia, and desaturations have been reported (1). There is also great variation in the delivery methods and positioning of infants during surfactant administration. Controversy also remains regarding the safety and effectiveness of various surfactant formulations and animal-derived vs. synthetic products, with some studies indicating no difference and others favouring animal-derived formulations. I have personal experience with three formulations: bovine lipid extracted surfactant (bLES, a bovine extract available in Canada), beractant (Survanta), and poractant alpha (Curosurf). In my limited experience with Curosurf, I have found the need for second dosing higher than with bLES. Units in Canada used Survanta for approximately one year due to temporary closure of the facility that manufactures bLES. Anecdotally, I found the incidence of pneumothorax greater with Survanta (an observation shared informally between colleagues from other units). Survanta also has a slower onset of action and seemed to require a second dose more frequently than bLES. These observations are not consistent with some published literature (2). There are no studies comparing bLES to other formulations to the best of my knowledge, although calfactant appears to be more beneficial initially (3). That being said, another Toronto NICU was trading two vials of Survanta for one of our vials of bLES still in stock during that "year without bLES."

Neonatology Today, 2021

With COVID-19 ICU admissions at record levels in several Canadian jurisdictions, this month, I wi... more With COVID-19 ICU admissions at record levels in several Canadian jurisdictions, this month, I will stray from the NICU to the ICU. (With full admission that adult ventilation is not my field of specialty). High-frequency jet ventilation (HFJV) has been used in the NICU for decades. It has proven beneficial in treating varying pathologies, such as pneumothoraces, broncho-pleural fistulae, and pulmonary interstitial emphysema (PIE).

Neonatology Today, 2021

Ever since mechanical ventilators were first used on babies nearly 60 years ago, the consequences... more Ever since mechanical ventilators were first used on babies nearly 60 years ago, the consequences of positive pressure ventilation (PPV) have been apparent. Despite many advancements in the technology behind mechanical ventilators, normal breathing involves negative pressure, and PPV is fundamentally unnatural. Despite the best of intentions and use of lung-protective ventilation strategies, PPV too often results in abnormal pulmonary development with attending long-term sequelae. While the whole may be greater than the sum of its parts, the failure of one of those parts makes that part the most valuable of all. This is never more so than when the lungs fail. The failure of lungs before they have fully developed presents a veritable quagmire akin to a whack-a-mole game from hell; the fix for one problem creates or is the opposite fix for another. Pulmonary development is at its infancy (no pun intended) in the sub-25-week post-conceptual age (PCA) baby, and barely able to sustain life, let alone growth at 22 weeks PCA. Be that as it may, Dr. Jonathan Klein of Iowa has shown us that with extreme skill, these infants can and do survive and grow, albeit after a long, costly course in the hospital. Even with the best of care, much of the NICU stay is spent recovering from our efforts to keep them alive.

Neonatology Today, 2021

We are accustomed to referring to the first hour of a baby's life as "the golden hour." If the fi... more We are accustomed to referring to the first hour of a baby's life as "the golden hour." If the first hour is golden, then the first ten minutes of that hour are platinum.

Neonatology Today, 2021

In June's Neonatology Today column we discussed "just right" values relating to PaCO 2. This mont... more In June's Neonatology Today column we discussed "just right" values relating to PaCO 2. This month's focus is on oxygen. In utero development occurs in a relatively hypoxic environment with PaO 2 of approximately 20 mmHg, (1) thus even room air represents a hyperoxic environment to the newborn infant. To protect the infant from hyperoxia and resulting formation of reactive oxygen species (ROS) (free radicals), just prior to term gestation non-enzymatic antioxidants (i.e. glutathione, vitamins C and E, and carotenoids) cross the placenta and endogenous antioxidant systems are up-regulated immediately prior to birth and are further up-regulated upon exposure to room air. Glutathione (GSH) is by far the most abundant antioxidant in the human body, and premature infants have low levels of GSH. (2)

Neonatology Today, 2021

Despite being used routinely for over 30 years, controversies remain regarding the method of admi... more Despite being used routinely for over 30 years, controversies remain regarding the method of administration and surfactant formulations themselves. Adverse events such as spontaneous airway obstruction, pneumothorax, pulmonary hemorrhage, changes in cerebral perfusion, bradycardia, and desaturations have been reported (1). There is also great variation in the delivery methods and positioning of infants during surfactant administration. Controversy also remains regarding the safety and effectiveness of various surfactant formulations and animal-derived vs. synthetic products, with some studies indicating no difference and others favouring animal-derived formulations. I have personal experience with three formulations: bovine lipid extracted surfactant (bLES, a bovine extract available in Canada), beractant (Survanta), and poractant alpha (Curosurf). In my limited experience with Curosurf, I have found the need for second dosing higher than with bLES. Units in Canada used Survanta for approximately one year due to temporary closure of the facility that manufactures bLES. Anecdotally, I found the incidence of pneumothorax greater with Survanta (an observation shared informally between colleagues from other units). Survanta also has a slower onset of action and seemed to require a second dose more frequently than bLES. These observations are not consistent with some published literature (2). There are no studies comparing bLES to other formulations to the best of my knowledge, although calfactant appears to be more beneficial initially (3). That being said, another Toronto NICU was trading two vials of Survanta for one of our vials of bLES still in stock during that "year without bLES."

Neonatology Today, 2021

With COVID-19 ICU admissions at record levels in several Canadian jurisdictions, this month, I wi... more With COVID-19 ICU admissions at record levels in several Canadian jurisdictions, this month, I will stray from the NICU to the ICU. (With full admission that adult ventilation is not my field of specialty). High-frequency jet ventilation (HFJV) has been used in the NICU for decades. It has proven beneficial in treating varying pathologies, such as pneumothoraces, broncho-pleural fistulae, and pulmonary interstitial emphysema (PIE).