Enhanced pulmonary function using dimethylthiourea for twelve-hour lung preservation.

Area of Science:

• Transplantation Biology
• Cardiovascular and Respiratory System Physiology
• Pharmacology

Background:

• Current lung preservation methods limit ischemic time to 6 hours, impacting transplant success.
• Extending preservation time is crucial for improving organ availability and patient outcomes in lung transplantation.

Purpose of the Study:

• To investigate the efficacy of dimethylthiourea (DMTU) as a free radical scavenger in prolonging lung preservation.
• To evaluate the impact of DMTU on lung function and survival following extended hypothermic storage and transplantation.

Main Methods:

• A canine lung transplantation model was employed to assess lung function after preservation.
• Donor lungs were flushed with modified Euro-Collins solution containing either DMTU (5 g) or saline, followed by 12-hour hypothermic storage at 4°C.
• Lungs were transplanted into recipient dogs, and functional parameters were monitored for 8 hours post-reperfusion.

Main Results:

• All dogs receiving DMTU treatment survived the 8-hour observation period, while one-third of the control group (saline) did not survive.
• DMTU-treated lungs exhibited significantly higher arterial oxygen tension (PaO2) compared to controls.
• Pulmonary vascular resistance (PVR) was significantly lower in the DMTU group, indicating improved pulmonary hemodynamics.

Conclusions:

• Dimethylthiourea effectively improves pulmonary function and survival after extended (12-hour) hypothermic lung storage in a canine model.
• DMTU's properties as a free radical scavenger mitigate ischemic injury, offering a potential strategy to extend lung preservation intervals.
• This study suggests DMTU as a promising adjunct for enhancing lung transplant viability and outcomes.