1. Great case, extremely complicated. Nightmare for anyone.
2. If you feared BIPAP would kill pt, wouldn’t possible pressure after intubation be similar? Might have tried “lowish” BIPAP settings to hopefully improve pulm mechanics, decrease work of breathing, lower PaCO2
3. Likely deterioration was induction of anesthesia, not positive pressure. As PICU doc and pediatric anesthesiologist, would have strongly considered blind nasal intubation. Have had luck w teenagers in severe heart failure literally inhaling endotracheal tube w gasping respiratory effort, then starting gentle positive pressure, rate 10-12, PEEP 5-ish and inspiratory time 1s or less to let Fontan heart fill passively. If rate = 10/min and I-time is 1s, then 10s of the 60s resp cycle is inspiration and 50s allows no effect from positive pressure except minimal PEEP that hopefully helps lungs more than it hurts heart.
4. Fontan patients can and do tolerate positive pressure. In fact, a successful Fontan post-op returns to PICU anesthetized, on ventilatory settings not unlike mentioned above…and pt has normal blood pressure, heart rate.
5. Getting beyond my expertise, but positive pressure obviously can impair venous filling, a problem for Fontan patients. The positive pressure can actually help the failing ventricle by “reducing afterload” by functionally compressing ventricle and facilitating ejection during the judicious use of “just enough” positive pressure balanced with intervals allowing venous return.
6. I once had Fontan pt w poor ventricular function on mechanical ventilation and some pressors. Pt was “stable”; I watched my colleague wean and extubate pt with idea that “Fontans do better w spontaneous ventilation”. Pt immediately deteriorated, but was fortunately able to be re-intubated and quickly stabilize.
7. In retrospect, I think BIPAP as temporizing measure while getting pressors started at low dose, BIPAP buying time while preparing for blind nasal intubation…all biased by knowing that induction agents or induction itself resulted in immediate cardiac arrest.
8. I am going to forward to a pediatric anesthesia forum for their more expert comments.
Hi Robert! Thank you for such a thoughtful reply! I appreciate all of your thoughts and comments. I agree, quite a scary scenario, even for the most seasoned of clinicians. Running through your thoughts, I agree, positive pressure after intubation would likely be just as bad as the positive pressure from BiPAP. When talking to some of my congenital cardiology colleagues, they recommended considering avoiding paralytics at all, so the patient could breathe on his/her own. I think what you describe in point 3 is a great idea for crashing heart failure kiddos. I, personally, do not have much, if any, experience with blind nasal intubations, but what you describe seems very reasonable and effective. Looking at your points 4, 5, and 6, I see your point that these patients can tolerate positive pressure, but I am still cautions in the ER to use much, if any positive pressure. My understanding is that too much positive pressure will increase their intrathoracic pressure and then decrease their pulmonary blood flow. Eventually, this would decrease their preload, causing their pressure to drop. When you have these patients in the PICU, post-op, do you keep the settings low to allow for mostly passive filling, like you describe in point 3? It seems reasonable to me that they can likely tolerate and even at times be helped by very minimal positive pressure. I’m very interested to know what your pediatric anesthesia colleagues think, please let me know! Again, I really appreciate all of your thoughtful comments, thank you!
What are the downsides to prophylactically starting a epi push or infusion prior to intubation. For patients with distributive or hypovolemic shock I’ve seen this used well - obviously I don’t know the first thing about the congenital cardiac surgery population
1. Great case, extremely complicated. Nightmare for anyone.
2. If you feared BIPAP would kill pt, wouldn’t possible pressure after intubation be similar? Might have tried “lowish” BIPAP settings to hopefully improve pulm mechanics, decrease work of breathing, lower PaCO2
3. Likely deterioration was induction of anesthesia, not positive pressure. As PICU doc and pediatric anesthesiologist, would have strongly considered blind nasal intubation. Have had luck w teenagers in severe heart failure literally inhaling endotracheal tube w gasping respiratory effort, then starting gentle positive pressure, rate 10-12, PEEP 5-ish and inspiratory time 1s or less to let Fontan heart fill passively. If rate = 10/min and I-time is 1s, then 10s of the 60s resp cycle is inspiration and 50s allows no effect from positive pressure except minimal PEEP that hopefully helps lungs more than it hurts heart.
4. Fontan patients can and do tolerate positive pressure. In fact, a successful Fontan post-op returns to PICU anesthetized, on ventilatory settings not unlike mentioned above…and pt has normal blood pressure, heart rate.
5. Getting beyond my expertise, but positive pressure obviously can impair venous filling, a problem for Fontan patients. The positive pressure can actually help the failing ventricle by “reducing afterload” by functionally compressing ventricle and facilitating ejection during the judicious use of “just enough” positive pressure balanced with intervals allowing venous return.
6. I once had Fontan pt w poor ventricular function on mechanical ventilation and some pressors. Pt was “stable”; I watched my colleague wean and extubate pt with idea that “Fontans do better w spontaneous ventilation”. Pt immediately deteriorated, but was fortunately able to be re-intubated and quickly stabilize.
7. In retrospect, I think BIPAP as temporizing measure while getting pressors started at low dose, BIPAP buying time while preparing for blind nasal intubation…all biased by knowing that induction agents or induction itself resulted in immediate cardiac arrest.
8. I am going to forward to a pediatric anesthesia forum for their more expert comments.
Hi Robert! Thank you for such a thoughtful reply! I appreciate all of your thoughts and comments. I agree, quite a scary scenario, even for the most seasoned of clinicians. Running through your thoughts, I agree, positive pressure after intubation would likely be just as bad as the positive pressure from BiPAP. When talking to some of my congenital cardiology colleagues, they recommended considering avoiding paralytics at all, so the patient could breathe on his/her own. I think what you describe in point 3 is a great idea for crashing heart failure kiddos. I, personally, do not have much, if any, experience with blind nasal intubations, but what you describe seems very reasonable and effective. Looking at your points 4, 5, and 6, I see your point that these patients can tolerate positive pressure, but I am still cautions in the ER to use much, if any positive pressure. My understanding is that too much positive pressure will increase their intrathoracic pressure and then decrease their pulmonary blood flow. Eventually, this would decrease their preload, causing their pressure to drop. When you have these patients in the PICU, post-op, do you keep the settings low to allow for mostly passive filling, like you describe in point 3? It seems reasonable to me that they can likely tolerate and even at times be helped by very minimal positive pressure. I’m very interested to know what your pediatric anesthesia colleagues think, please let me know! Again, I really appreciate all of your thoughtful comments, thank you!
I wrote a heart attack from the pacemaker's point of view.
https://open.substack.com/pub/thebiologicalimagination/p/the-funerals-i-held-in-silence?utm_campaign=post-expanded-share&utm_medium=web
What are the downsides to prophylactically starting a epi push or infusion prior to intubation. For patients with distributive or hypovolemic shock I’ve seen this used well - obviously I don’t know the first thing about the congenital cardiac surgery population
Acute MI