Comparison of the effects of lactated Ringer solution with and without hydroxyethyl starch fluid resuscitation on gut edema during severe splanchnic ischemia

The type of fluid used during resuscitation may have an important impact on tissue edema. We evaluated the impact of two different regimens of fluid resuscitation on hemodynamics and on lung and intestinal edema during splanchnic hypoperfusion in rabbits. The study included 16 female New Zealand rabbits (2.9 to 3.3 kg body weight, aged 8 to 12 months) with splanchnic ischemia induced by ligation of the superior mesenteric artery. The animals were randomized into two experimental groups: group I (N = 9) received 12 mL·kg-1·h-1 lactated Ringer solution and 20 mL/kg 6 percent hydroxyethyl starch solution; group II (N = 7) received 36 mL·kg-1·h-1 lactated Ringer solution and 20 mL/kg 0.9 percent saline. A segment from the ileum was isolated to be perfused. A tonometric catheter was placed in a second gut segment. Superior mesenteric artery (Q SMA) and aortic (Qaorta) flows were measured using ultrasonic flow probes. After 4 h of fluid resuscitation, tissue specimens were immediately removed for estimations of gut and lung edema. There were no differences in global and regional perfusion variables, lung wet-to-dry weight ratios and oxygenation indices between groups. Gut wet-to-dry weight ratio was significantly lower in the crystalloid/colloid-treated group (4.9 ± 1.5) than in the crystalloid-treated group (7.3 ± 2.4) (P < 0.05). In this model of intestinal ischemia, fluid resuscitation with crystalloids caused more gut edema than a combination of crystalloids and colloids.

The Comparative Effect of Fentanyl and Isoflurane on Splanchnic Perfusion during Cardiac Surgery / 대한마취과학회지

BACKGROUND: Splanchnic perfusion derangement commonly occurs during cardiac surgery, while splanchnic ischemia is known to increase morbidity in surgical and critically ill patients. We hypothesized that anesthetic agents may have different effects on splanchnic perfusion during cardiac surgery. METHODS: Twenty-four patients undergoing cardiac surgery were randomly divided into fentanyl (n = 12) and isoflurane (n = 12) groups. Gastric intramucosal PrCO2 and pHi were measured using tonometry. Patient temperature was maintained at 28 degrees C during cardiopulmonary bypass (CPB). Measurements were made at the following times: (1) baseline, after the induction of anesthesia, (2) 30 minutes into CPB, (3) 60 minutes into CPB, (4) at the end of CPB, (5) one hour after CPB, and (6) 24 hours after CPB. Statistical analysis was performed using repeated measures of ANOVA and the unpaired t-test. RESULTS: The observed hemodynamic changes were similar in both groups. The pHi decreased significantly during hypothermic CPB and remained in this attenuated state up to 24 hours postoperatively in both groups. The pHi in the isoflurane group began to decrease at 30 minutes after starting CPB while that in the fentanyl group decreased at 60 minutes after starting CPB. The pHi of isoflurane group was significantly lower than that of the fentanyl group during CPB and 1 hour after the end of CPB. However, the pHi at 24 hours after CPB was similar in both groups. CONCLUSIONS: We conclude that fentanyl provides more protection from splanchnic ischemic insult than isoflurane during cardiac surgery with hypothermic CPB.

The Effect of Low-dose Dopamine on Splanchnic and Renal Blood Flow in Patients with Septic Shock under the Treatment of Norepinephrine / 대한구급학회지

BACKGROUND: Norepinephrine, which is frequently administered as a vasopressor to the patients with septic shock, can decrease splanchnic and renal blood flows and aggravate splanchnic and renal ischemia. The low-dose dopamine (LDD) has been frequently combined with norepinephrine to ameliorate renal and splanchnic hypoperfusion in patients with septic shock. However, the effect of the LDD on the splanchnic and renal blood flow has not been fully elucidated. This investigation was carried out to determine the effect of the LDD on the splanchnic and renal blood flow in the patients with septic shock under the treatment of norepinephrine. METHODS: Eleven patients with septic shock were included in this study. All of them were under the norepinephrine treatment as the mean arterial pressure (MAP) was less than 70 mm Hg in spite of the adequate fluid resuscitation. With stabilization of MAP, the LDD (2 g/kg/min) was administered for two hours in each patients. Hemodynamics, gastric intramucosal pH (pHi), gastric regional PCO2 (rPCO2), rPCO2 - PaCO2, urine volume, urine sodium excretion and creatinine clearance were compared between with and without the LDD infusion. Diuretics was not used during the study period. RESULTS: Age of patients (n=11) was 64 12 and the APACHE III score was 84 17. The mortality rate of the subjects was 64%. Dosage of norepinephrine was 0.55 0.63 g/kg/min during the study period. There were no significant differences in hemodynamics (central venous pressure, cardiac output, pulmonary artery occlusion pressure, mixed venous gas), pHi, rPCO2, rPCO2 - PaCO2 depending on the concomitant infusion of the LDD. The volume of urine tended to increase (P=0.074) after concomitant LDD, but the changes in urine sodium excretion and creatinine clearance were not significantly different. CONCLUSIONS: The combined infusion of the LDD with norepinephrine did not improve splanchnic and renal blood flow in the patients with septic shock.