Triiodothyronine resuscitates the impaired liver function after Pringle's maneuver

To evaluate the changes in thyroid hormone levels and the effectiveness of exogenous triiodothyronine (T3) in shock caused by prolonged use of Pringle's maneuver (cross-clamping of hepatic triads).

Pringle's maneuver was performed on dogs for 1 hour. In the T3 group (n = 7), 1 microgram/kg per hour of T3 was administered intravenously for 3 hours after declamping. In the control group (n = 7), the same volume of saline solution without T3 was administered.

Serum T3, reverse T3, thyroxine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and the ketone body ratio (AKBR), which reflect the hepatic energy charge, were measured. Tissue blood flow, tissue blood velocity, and tissue blood mass of the liver were measured by means of a laser Doppler flowmeter. Oxygen saturation of the hemoglobin in the liver tissue was measured by tissue near-infrared spectroscopy. Dogs were observed until the seventh postoperative day.

In the control group, the low T3 syndrome was observed. None of the dogs recovered from the shock and none survived for more than 24 hours. In the T3 group, all dogs recovered from the shock and survived. In the control group, hepatic tissue blood flow and oxygen saturation of hemoglobin in liver tissue were decreased, and the AKBR was deteriorated. In the T3 group, however, these parameters were markedly improved.

It is suggested that T3 administration is beneficial in managing the critical resuscitation period of liver function after Pringle's maneuver is performed in dogs.