Efficacy of peritoneal oxygenation using a novel artificial oxygen carrier (TRM-645) in a rat respiratory insufficiency model.
OBJECTIVE
Supplemental oxygenation is essentially important in critically ill patients with potentially reversible pulmonary insufficiency. An extracorporeal membrane oxygenator and percutaneous cardiopulmonary support have been used for these patients. However, these techniques are associated with so many complications that an additional new therapeutic modality is required. The purpose is to investigate if the peritoneal cavity can be used as "extrapulmonary respiration" that is analogous to peritoneal dialysis and utilizes the efficacy of liposome-encapsulated hemoglobin (artificial oxygen carrier; TRM-645).


METHODS
Rats weighing an average of 300 g (n = 18) received an incision in the right chest to generate pneumothorax, which resulted in severe and lethal hypoxia. Oxygenated TRM-645 and human red blood cells (MAP group) were administered into the peritoneum in the experimental rats' pneumothorax model. No treatment except the right pneumothorax was administered to the sham group.


RESULTS
Survival times from the pneumothorax were significantly longer in the TRM-645 and MAP groups than in the sham group (32.0 +/- 6.9 and 22.0 +/- 4.9 min vs 9.2 +/- 1.9 min, P < 0.01). In addition, an arterial blood gas analysis showed that the oxygenation in levels significantly improved.


CONCLUSIONS
The abdomen (peritoneum) can potentially become an "artificial lung" that can be employed in critical care settings. TRM-645 provides an alternative to the use of washed human red blood cells.
Matsutani
Noriyuki
N
Department of Surgery II, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan.
Takase
Bonpei
B
Nogami
Yashiro
Y
Ozeki
Yuichi
Y
Kaneda
Shinichi
S
Maehara
Tadaaki
T
Kikuchi
Makoto
M
Ishihara
Masayuki
M
D000818:Animals; D001784:Blood Gas Analysis; D001802:Blood Substitutes / Q000494:pharmacology*; D004195:Disease Models, Animal; D017707:Erythrocyte Transfusion; D006454:Hemoglobins / Q000494:pharmacology*; D006801:Humans; D008081:Liposomes / Q000494:pharmacology*; D010100:Oxygen / Q000378:metabolism*; D010537:Peritoneum / Q000378:metabolism*; D011031:Pneumothorax, Artificial; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012131:Respiratory Insufficiency / Q000503:physiopathology / Q000628:therapy*; D015996:Survival Rate
D001802:Blood Substitutes; D006454:Hemoglobins; D008081:Liposomes; D010100:Oxygen