Monitoring of gastric PCO2 for evaluation of splanchnic mucosal microcirculatory impairment during mesenteric venous occlusion and reperfusion

Laparoscopic-assisted combined colon and liver resection for primary colorectal cancer with synchronous liver metastases: initial experience

BACKGROUND

Laparoscopic approaches have become increasingly used in selected patients with either colorectal or liver cancer. However, the feasibility of laparoscopic-assisted combined colon and liver resection in primary colorectal cancer with synchronous liver metastases remains unknown. The aim of the present study was to determine the feasibility of laparoscopic-assisted combined colon and liver resection for primary colorectal cancer with synchronous liver metastases.

METHODS

Laparoscopic surgery involving intestinal anastomosis was performed for primary colorectal cancer. The liver was then mobilized with the assistance of a hand inserted through the upper midline incision. For minor resections, the parenchymal transection was performed laparoscopically. For major resection involving a hilar dissection, transection was performed according to the standard open techniques under direct vision through the incision. Resected specimens were retrieved directly through the midline incision.

RESULTS

Ten patients with primary colorectal cancer and synchronous liver metastases underwent the above procedure between September 2006 and April 2007. Surgical procedures for colorectal cancer included 5 low anterior resections, 3 anterior resections, 1 right hemicolectomy, and 1 subtotal colectomy. Combined hepatic surgery included 6 major hepatectomies, 3 segmentectomies, and 1 tumorectomy. All procedures were successful, with no conversions to open surgery required. The median operation time was 439 min (range: 210-690 min), and the median estimated blood loss was 350 ml (range: 300-1,200 ml). There was no surgical mortality or major morbidity, except in one patient in whom postoperative bleeding at the site of para-aortic node dissection was promptly controlled.

CONCLUSIONS

Laparoscopic-assisted combined colon and liver resection is a feasible and safe procedure for the treatment of primary colorectal cancer with synchronous liver metastases.

Effects of amrinone in an experimental model of hepatic ischemia-reperfusion injury

BACKGROUND

During some surgical interventions, temporary occlusion of the hepatic blood supply may cause ischemia-reperfusion (IR) injury. Recent studies suggest that type 3 phosphodiesterase inhibitors may have a beneficial effect on liver IR injury. The aim of this study was to investigate whether amrinone, a type 3 phosphodiesterase inhibitor, could have a protective effect on liver having experimental liver IR injury.

MATERIALS AND METHODS

Sixty Wistar albino rats were randomly divided into three groups. The IR and amrinone groups were subjected to 1 h total hepatic ischemia, followed by 2 h of reperfusion. The sham group underwent midline laparotomy only. Amrinone 10 microg/kg/min was infused to the amrinone group during the 3 h of the IR period. Histopathological examination, biochemical liver function, and liver adenosine triphosphate concentration after reperfusion and survival rate on the seventh day after the IR insult were recorded.

RESULTS

Serum aspartate aminotransferase, alanine aminotransferase, lactic dehydrogenase levels, and histological damage scores in the amrinone and IR groups were significantly higher compared with the sham group (P < 0.01). However, all of these values were significantly lower in the amrinone group than in the IR group (P < 0.05). Liver adenosine triphosphate levels and the rat survival rate in the amrinone and IR groups were significantly lower than those in the sham group (P < 0.01). However, these values were significantly higher in the amrinone group compared to those in the IR group (P < 0.01).

CONCLUSIONS

These results suggest that amrinone plays a significant role in the protection of liver against IR injury and that this treatment may be a novel pharmacological agent for safe and efficient liver surgery.

Active spleno-femoral shunt avoids splanchnic congestion during portal triad occlusion: an experimental study

Portal triad occlusion (PTO) is often performed during hepatic resections for trauma or malignancies to minimize intraoperative blood loss. The pringle maneuver is also regularly required during liver transplantation. This maneuver leads to temporary hepatic ischemia and may be associated with splanchnic blood flow congestion, promoting undesirable hemodynamic disturbances in some patients. Veno-venous bypass is a useful, easily performed technique that may avoid those deleterious hemodynamic effects of PTO. We tested the hypothesis that an active spleno-femoral shunt maintains hemodynamic stability and promotes complete decompression of the mesenteric bed, avoiding intestinal mucosal blood congestion, during PTO.

METHODS

Seven dogs (17.2 +/- 0.9 kg) were subjected to 45 minutes of hepatic ischemia during which there was an active spleno-femoral shunt. Systemic hemodynamics were evaluated through Swan-Ganz and arterial catheters. Splanchnic perfusion was assessed by portal vein blood flow and hepatic artery blood flow (PVBF and HABF, ultrasonic flowprobe), intestinal mucosal-arterial pCO(2) gradient (D(t-a)pCO(2), tonometry), and regional O(2)-derived variables.

RESULTS

No significant changes in systemic and regional parameters were observed during the ischemia period. During reperfusion, a significant decrease in mean arterial pressure, PVBF, and arterial pH was observed. A significant increase in ALT and D(t-a)pCO(2) (4.8 +/- 2.5 to 18.9 +/- 3 mm Hg) was also observed following hepatic blood flow restoration.

CONCLUSION

Spleno-femoral shunt maintains systemic hemodynamic stability, with an effective decompression of the splanchnic bed during portal triad occlusion. The deleterious hemodynamic and metabolic effects observed during reperfusion period, such as transitory hypotension, high D(t-a)pCO(2), and acidemia, were associated with an isolated hepatic ischemia-reperfusion injury, not with the blood congestion in the splanchnic bed.