Effect of Elevated Intra-Abdominal Pressure on Portal Vein and Superior Mesenteric Artery Blood Flow in a Rat

Effect of intraabdominal hypertension on splanchnic blood flow in children with appendicular peritonitis

Background and Aims:

Intraabdominal hypertension (IAH) is poorly diagnosed condition that cause splanchnic hypoperfusion and abdominal organs ischemia and can lead to multiple organ failure. There are no scientific data regarding effect of intraabdominal pressure (IAP) on splanchnic circulation in children.

Material and Methods:

Ninety-four children after surgery for appendicular peritonitis were enrolled in the study. After IAP measurement children were included in one of two groups according IAP levels: “without IAH” (n = 51) and “with IAH” (n = 43). Superior mesenteric artery (SMA) and portal vein (PV) blood flows (BF_SMA, BF_PV, mL/min) were measured, and SMA and PV blood flow indexes (BFI_SMA, BFI_PV, ml/min*m2) and abdominal perfusion pressure (APP) were calculated in both groups.

Results:

Median BFI_SMA and BFI_PV in group “with IAH” were lower by 54.38% (P < 0.01) and 63.11% (P < 0.01) respectively compared to group “without IAH”. There were strong significant negative correlation between IAP and BFI_SMA (r_s = –0.66; P < 0.0001), weak significant negative correlation between IAP and BFI_PV (r_s = –0.36; P = 0.0001) in group “with IAH” and weak significant negative correlation between IAP and BFI_SMA (r_s = –0.30; P = 0.0047) in group “without IAH”. There were no statistically significant correlations between IAP and BFI_PV in group “without IAH”, between BFI_SMA and APP in both groups and between BFI_PV and APP in both groups.

Conclusion:

Elevated IAP significantly reduces splanchnic blood flow in children with appendicular peritonitis. BFI_SMA and BFI_PV negatively correlate with IAP in these patients. There is no correlation between BFI_SMA/BFI_PV and APP in children with IAH due to appendicular peritonitis.

Deepening of sedation with propofol has limited effect on intra-abdominal pressure - An interventional study in mechanically ventilated adult patients with intra-abdominal hypertension

PURPOSE

To evaluate the effect of deepening of sedation on intra-abdominal pressure (IAP).

METHODS

37 adult mechanically ventilated ICU patients with intra-abdominal hypertension received a bolus dose and subsequent infusion of propofol (bolus: 1 mg/kg, infusion: 3 mg/kg/h). IAP, mean arterial pressure (MAP), abdominal perfusion pressure (APP), depth of sedation according to Richmond Agitation-Sedation Scale (RASS), respiratory parameters, and vasopressor dose were assessed after bolus and at 15, 30 and 60 min of infusion of propofol.

RESULTS

Median IAP at baseline was 15 (13-16) mm Hg. During the intervention, median IAP decreased by 1 mm Hg at all time points. In 24% of patients IAP decreased by ≥3 mm Hg. Compared to baseline, MAP and APP were reduced at all time points. Deepening of sedation per RASS was achieved in 70% of patients at all time points. No changes in respiratory tidal volumes nor plateau pressures were observed. Vasopressor therapy with noradrenaline was started or increased in 43% of patients, whereas the increase in patients already receiving noradrenaline prior to the intervention was not significant.

CONCLUSIONS

Deepening of sedation with propofol results in a small decrease in IAP and greater simultaneous decrease in MAP and APP, requiring increased vasopressor support in some cases.

Fumigant toxicity of some essential oils against Red Flour Beetles, Tribolium castaneum (Herbst) and its safety to mammals

Fumigant activities for three essential oils; Garlic oil (Allium sativum L); Chili pepper (Capsicum annuum L.) and Nigella (Nigella sativa L.) were assessed at different concentrations against the adult and 20-days old larval stages of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) in the laboratory. The accumulative mortality was observed at different exposure periods (3, 5 and 7 days). The residual effect of garlic oil that was the effective oil, on the treated wheat grains was evaluated with respect to histological changes in the liver, kidney, and stomach of rat fed on this treated wheat. The results showed that the mortality rates of treated stages increased with increasing the time of fumigation treatment. Moreover the highest essential oils toxicity at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (126, 53, and 47 mg/L air) for adult stage and were (79, 62, and 41 mg/L air) for larval stage, respectively in the case of Garlic oil treatment. While, the lowest essential oils effective was Nigella oil at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (3594, 629, and 335 mg/L air) for adult stage and were (1040, 416, and 227 mg/L air) for larval stage, respectively. The toxicity effect of various essential oils against adults and larvae of T. castaneum at the LC50at 7 days fumigation could be arranged in descending order as follows: Garlic oil, Chili pepper oil, and Nigella oil. The histological changes showed that the organs slightly affected at the fumigation for 3 days. It may be concluded that the garlic essential oil is the good effective fumigant to control T. castaneum in the stored products and it recommended that the fumigation period does not exceed 3 days. The garlic essential oil has the potential for applications in IPM programs for stored-grain pests because of its high volatility and fumigant activity and its safety.

Effect of pneumoperitoneum on the recovery from intense neuromuscular blockade by rocuronium in healthy patients undergoing laparoscopic surgery

BACKGROUND

This study investigated the effect of pneumoperitoneum on the recovery from intense neuromuscular blockade by rocuronium in healthy patients undergoing laparoscopic abdominal surgery.

METHODS

Thirty adult patients undergoing laparoscopic abdominal surgery were studied. Anesthesia was induced with 1.5 mg/kg of propofol, 12 ug/kg of alfentanil and 0.6 mg/kg of rocuronium and maintained with 2 vol% of sevoflurane and 0.05-0.2 µg/kg/min remifentanil. The neuromuscular relaxation was monitored by Train-of-Four (TOF) and post-tetanic count (PTC). Additional rocuronium of 0.2 mg/kg was administered for deep neuromuscular blockade at 30 min after pneumoperitoneum. Before (PPpre) and 30 min after pneumoperitoneum (PPpost), PTC was measured at 6 min intervals. The relationship between PTC and the time interval to reappearance of T1 response was observed.

RESULTS

The mean ± SD of the intervals between the detection of 4 counts of the PTC and the first response to TOF stimulation was 13.0 ± 1.1 min and 16.4 ± 6.3 min PPpre and PPpost, respectively (P = 0.20). There were significant negative relationships between PTC observed and the time interval to reappearance of T1 response (adjusted R(2) = 0.869, P < 0.001 for PPpre data, and adjusted R(2) = 0.561, P < 0.001 for PPpost data). Comparing the difference of regression equation between PPpre and PPpost data using a parallelism test, there was no statistically significant difference (P = 0.193).

CONCLUSIONS

This study showed that PP with intra-abdominal pressure at the level of 13-14 mmHg did not affect the recovery from intense neuromuscular blockade by rocuronium in healthy patients undergoing laparoscopic abdominal surgery.

Effects of carbon dioxide pneumoperitoneum on hepatic and renal morphology of rats after segmental colectomy and colonic anastomosis

PURPOSE

To evaluate the effects of increased intraperitoneal pressure caused by carbon dioxide pneumoperitoneum on the hepatic and renal morphology of rats.

METHODS

Fifty-four adult male rats were randomly divided into three groups (P, PP and C) after anesthesia: P - in 18 animals, pneumoperitoneum was established for 30 minutes immediately before laparotomy; PP - in 18 animals, pneumoperitoneum was established for 60 minutes divided into 30 immediately before laparotomy and 30 after abdominal closure; control group (C) - 18 animals underwent laparotomy without pneumoperitoneum induction. The pneumoperitoneum was maintained at a pressure of 5 mm Hg. Nine animals in each group were killed on the 3(rd) and 7(th) postoperative days, when kidney and liver samples were collected for morphological analysis. The liver specimens were stained with hematoxylin and eosin (HE), and the kidney specimens, with HE and von Kossa. Blinded examiners analyzed the slides.

RESULTS

No changes in renal morphology were found. Liver samples showed histological signs of degeneration in animals in the pneumoperitoneum groups killed on the 7(th) postoperative day (p=0.029).

CONCLUSION

The CO(2) pneumoperitoneum did not affect renal morphology but caused hydropic degeneration in the liver of animals killed on the 7(th) postoperative day.