Adrea Kristofy, M.D., attending anesthesiologist at Kosair Children’s Hospital, discusses single lung ventilation in pediatrics. Dr Kristofy is an Assistant Professor of Anesthesiology at the University of Louisville School of Medicine. She is also a Diplomate of the American Board of Anesthesiology.
Single Lung Ventilation In Pediatrics
The goal is to answer 2 questions:
- How do we determine the need for single lung ventilation?
- How do we proceed once we have made that decision?
Indications for Single Lung Ventilation.
- Absolute Indications – Isolate on lungs because of Contamination, Infection, Bleeding, control of ventilation for bronchopleural fistula, large cyst, ect..
- Relative Indications – Surgical Exposure, thoracic aortic aneurysm, pneumonectomy, ect…
Three Different techniques used to achieve single lung ventilation.
- Simplest – Single tube right or left mainstem, right easier than left.
- Balloon tip bronchial blocker such as uninvent tube.
- Double lumen tubes.
Downside with single lumen tube only.
Inadequate seal, failure of lung to collapse, easier to get contamination from one side to the other.
Balloon tip bronchial blockers.
Can be placed on either side.
Can be dislodged somewhat easily.
Balloon low volume and high pressure.
Can Not suction threw the bronchial blocker.
Discrepancy between outer and inner lining of the tube and be problematic in small children
Double Lumen Endotracheal Tubes
Most common is the Carlens tube, carinal hook endotracheal tubes used in the past.
Two tubes equal length, with two cuffs one tracheal cuff and one bronchial cuff.
The size is measured in French not in millimeters.
So a 26fr double lumen endotracheal tube has an outer diameter of 9.3mm.
Advantages of Double lumen tubes
You can provide positive pressure ventilation
You can suction either the operative or the non-operative lung as needed
The cuffs are high volume and low pressure
One thing to remember with pediatrics and double lumen tubes is that a size 26fr corresponds with approximately at 5.5-6mm cuffed singled lumen endotracheal tube.
So if your patient can tolerated that size single lumen tube then they can tolerate a double lumen tube.
Physiologic concerns with single lung ventilation.
If decrease in saturation occurs check: Is the tube dislodged, secretions.
Most of the time desaturation occurs because of mismatch of ventilation and perfusion. To help fix this add CPAP to non-dependent, non-ventilated lung or add PEEP to ventilated lung. May have decrease TV and increase frequency to keep ventilation pressures the same.
If desaturation continues talk with your surgeon to see if you can intermittently re-expand the operative lung.
If still no increase in saturation then the surgeon may be able to put a temporary or possibly a permanent ligature on the pulmonary artery.
If all else fails talk with the surgeon and go directly to re-expansion of both lungs then continue trouble shooting.
Hammer, G. B., Fitzmaurice, B. G., & Brodsky, J. B. (1999). Methods for Single-Lung Ventilation in Pediatric Patients. Anesthesia & Analgesia, 89(6), 1426 1410.1213/00000539-199912000-199900019.