Can dantrolene protect spinal cord against ischemia/reperfusion injury? An experimental study.

BACKGROUND: The aim of this experimental study was to investigate the possible protective effect of dantrolene on neuronal injury induced by aortic ischemia/reperfusion (I/R). METHODS: Nineteen rabbits were divided into three groups: sham (group 1, n = 5, no I/R), control (group 2, n = 7, only I/R) and dantrolene (group 3, n = 7, dantrolene + I/R). Abdominal aortic occlusion between the renal arteries and iliac bifurcations was carried out for 30 min. The spinal cord functions of the subjects were assessed using the Tarlov Scale. Blood and cord tissue samples were taken for biochemical and histopathological evaluation. RESULTS: Tarlov scores in group 3 were significantly higher than in group 2 ( P < 0.05). In group 3, the MDA levels of the spinal cord decreased significantly compared to those of group 2 ( P < 0.05). In rabbits with I/R (group 2), the GSH levels of the spinal cord decreased significantly compared to those of group 1 ( P < 0.01), but dantrolene pretreatment significantly prevented a decrease in GSH levels. Histopathological examination showed that group 3 had less vascular proliferation, hemorrhage, edema and neuron loss than group 2. CONCLUSIONS: It was concluded that dantrolene applied after ischemia might help protect the spinal cord against ischemia/reperfusion injury.

Reconstruction of the vena cava with the peritoneum: the effect of temporary distal arteriovenous fistula on patency (an experimental study).

OBJECTIVE: To determine the effect of increasing inferior vena cava blood flow by means of distal arteriovenous fistula on the patency of a peritoneal tube graft. MATERIALS AND METHODS: In 16 mongrel dogs, a 3-4 cm long circular defect was created at the infrarenal inferior vena cava. The defect was interposed with peritoneal tube graft. A temporary distal femoro-femoral arteriovenous fistula was also constructed in 8 dogs just after the caval interposition. Graft patency was evaluated by Doppler ultrasonography and angiography. Histological evaluation was also performed. RESULTS: Seven dogs in each group survived. All control grafts occluded within the first week, compared to no occlusions in fistula group (Fisher's exact test, p<0.005). However one 'fistula' dog with a still patent graft was sacrificed on the 18th day due to ultrasonographically occluded arteriovenous fistula. CONCLUSION: In dogs, the peritoneum may be used as graft material for reconstruction of the inferior vena cava, provided a distal arteriovenous fistula is constructed.

Cardiac tamponade caused by an ingested sewing needle. A case report.

Ingested sharp-pointed foreign bodies can cause serious complications. A case of a 16-year-old girl with cardiac tamponade due to ingestion of a sewing needle is presented. Ingested needles have often been reported as a cause of gastrointestinal injuries but in this rare case the sewing needle actually migrated into the myocardium.

Reduction of spinal cord injury with pentobarbital and hypothermia in a rabbit model.

OBJECTIVES: to evaluate the effects of hypothermia and pentobarbital on spinal cord ischaemia induced in a rabbit model. MATERIALS AND METHODS: thirty-two rabbits, allocated into four equal groups, had the infrarenal aorta clamped distal to the left renal artery and above the iliac bifurcation for 40 min. Groups 3 and 4 had infusion of 15 mg/kg of pentobarbital intravenously for 5 min, 15 min before the cross-clamping. Groups 2 and 4 had infusion of 20 ml of Ringer's lactate (LR) solution at 3 degrees C for 3 min during aortic cross clamp into the isolated aortic segment. Group 1 was untreated and served as control. Postoperative functions of spinal cord were assessed. RESULTS: paraplegia occurred in all rabbits in Group 1, in one in each of Groups 2 and 3, whereas no paraplegia was observed in Group 4. In addition 2 and 3 animals of Groups 2 and 3, respectively revealed varying degree of neurological disturbances, whereas all animals of Group 4 had normal function. This difference between Groups 2, 3, and 4 vs Group 1 was significant (p<0.002). So was the difference between Groups 2 and 4 (p=0.03), whereas the difference between Groups 3 and 4 was not significant. CONCLUSIONS: hypothermia and pentobarbital was more effective than hypothermia alone for prevention of spinal cord ischaemia in a rabbit model.

Does aprotinin reduce lung reperfusion damage after cardiopulmonary bypass?

OBJECTIVE: The role of aprotinin in the prevention of lung reperfusion injury was investigated in the patients undergoing cardio-pulmonary bypass (CPB) for coronary artery bypass grafting (CABG) operations. METHODS: The study was planned randomly and prospectively. Two hundred milliliters of physiological saline solution was added to the prime solution of patients in group I (n=10) whereas, 200 ml aprotinin (Trasylol, Bayer AG) was given to patients in group II (n=10). In order to measure lung tissue malondialdehyde (MDA) levels, glutathion peroxidase (GSH-Px) activity levels and polymorphonuclear leukocytes (PMNs) numbers, lung tissue samples were taken before CPB and 5 min after removing the cross clamp. In addition, alveolo-arterial oxygen difference (AaDO(2)) for tissue oxygenation was calculated by obtaining arterial blood gas samples. RESULTS: MDA levels before CPB increased from 41.72+/-21.00 nmol/g tissue to 66.71+/-13.44 nmol/g tissue in group I and from 43.44+/-5.16 nmol MDA/g tissue to 53.22+/-10.95 nmol MDA/g tissue in group II after cross clamp removal (P=0.001 and P=0.021, respectively). The increase in group II was found to be significantly lower than group I (P=0.048). With the initiation of reperfusion, GSH-Px activity decreased in group I from 3.05+/-0.97 to 2.31+/-0.46 U/mg protein (P=0.015) whereas GSH-Px activity in group II decreased from 3.18+/-1.01 to 2.74+/-0.81 U/mg protein (P=0. 055). This decrease in the group II was less than group I (P=0.049). AaDO(2) significantly increased in the group I and II (P=0.012 and P=0.020, respectively), but elevation in the group I was significant than in the Group II (P=0.049). In histopathological examination, it was observed that neutrophil counts in the lung parenchyma rose significantly following removal of cross clamp in both groups (P=0. 001). The increase in group I was significantly larger than in group II (P=0.050). CONCLUSION: Results represented in our study indicate that addition of aprotinin (2 million units) into the prime solution during CPB can reduce lung reperfusion injury.