Pediatric patients with tetralogy of Fallot and pulmonary atresia appear to have an increased likelihood of complications following pulmonary rehabilitation surgery, according to a retrospective review.
The findings, presented at the 2017 annual meeting of the Society for Pediatric Anesthesia/American Academy of Pediatrics Section on Anesthesiology and Pain Medicine (abstract CA1-36), come from an analysis of the outcomes of 108 patients who received pulmonary artery angioplasty, with or without stent placement, between 2010 and 2015 at Nationwide Children’s Hospital, in Columbus, Ohio.
The investigators reviewed data on the diagnoses, procedures, anesthetic techniques used, whether or not bronchial blockers were used, incidence of pulmonary bleeding, vascular injury on chest X-ray, the postoperative course taken, and intraoperative hemodynamic data, including right ventricle/femoral artery (RV/FA) ratios (Table).
|Table. Periprocedural Data in Children|
|With TOF + Pulmonary Atresia||Without Condition||P Value|
|Preprocedure RV/FA ratio||1±0.1||0.8±0.3||0.0002|
|Branches dilated, n||4±1||3±2||0.00015|
|Postprocedure RV/FA ratio||0.9±0.1||0.6±0.2||<0.001|
|Complications, n (%)||14 (38.9)||14 (19.4)||0.04|
|Case time, minutes||278.4±84||230.4±82||0.008|
|RV/FA, right ventricle/femoral artery; TOF, tetralogy of Fallot|
They found that patients who have tetralogy of Fallot with pulmonary atresia (n=38), compared with those without the condition (n=72), experienced postoperative complications, specifically pulmonary hemorrhage and acute lung reperfusion injury, about twice as often (38.9% vs. 19.4%; P=0.04). Additionally, higher RV/FA pressure ratios increased the risk for complications.
Rosie Foster, MD, a pediatric anesthesiology fellow at Nationwide Children’s, said the findings were not surprising, but noted there is a paucity of data in this area in the literature. “The study helps verify our suspicions of patients who are higher risk. Patients with tetralogy of Fallot with pulmonary atresia are at higher risk when undergoing pulmonary artery rehabilitation procedures. It is beneficial to have a multidisciplinary discussion before the case to evaluate whether the patient is at higher risk for complications based on the underlying etiology of pulmonary stenosis, and the severity and burden of pulmonary stenosis.”
In the study, Dr. Foster and her colleagues noted that bronchial blockers were infrequently used, but this infrequency likely reflected the evolution of their practice, as their current protocol is to place a bronchial blocker at the beginning of the procedure in patients deemed to be at high risk for pulmonary hemorrhage, either through the lumen of the endotracheal tube or outside.
“Our experience has been that since these patients are higher risk, we should consider preemptively placing a bronchial blocker in the event of significant pulmonary hemorrhage or reperfusion injury,” she said.
“If you have significant hemorrhage or reperfusion injury that would affect your ability to oxygenate or ventilate adequately, you can quickly isolate the unaffected lung and perform one-lung ventilation. This prevents hemorrhage or reperfusion injury fluid from contaminating the unaffected lung and saves time while you’re trying to stabilize,” Dr. Foster said. “If you have severe hemorrhage or reperfusion injury without a bronchial blocker in place, you risk significant spillover into or contamination of the unaffected lung, which further compromises ability to oxygenate and/or ventilate while working to control the bleeding and attempting to achieve lung isolation. It’s a much more difficult situation.”
She noted further that patients with higher RV/FA pressure ratios are at higher risk for complications when undergoing pulmonary artery rehabilitation procedures.
Although this study confirmed her suspicions about which patients were at high risk, she wanted to see more data on the subject. “Any retrospective study gives you an idea of what you can do better with a prospective study,” she said.
Kelly Chilson, MD, director of pediatric cardiothoracic anesthesia in the Department of Anesthesiology at Washington University in St. Louis, said she would have expected to see a higher rate of complications in patients with tetralogy of Fallot with pulmonary atresia, but she would not have necessarily expected the relative rate of complications to be as high as it was. “I think it would be interesting to do a prospective look at the kids and see if you could predict, apart from the diagnosis, w hich ones would be likely to have complications.”
Dr. Chilson added that in her practice, she typically does not use bronchial blockers in this patient population. “If I have a patient who has really high right-sided pressures and tetralogy of Fallot with pulmonary atresia, I might consider that if there are going to be a lot of dilations being done. I think it might creep into practice, if they can better define the population of patients it might be indicated in.”