479 Penetrating Chest Trauma Causing A Superior Mesenteric Artery-Inferior Vena Cava Fistula and Pancreatic Injury: A Case Report

Penetrating traumatic injuries can present a challenging scenario due to the potential for multisystem involvement requiring swift collaboration between surgical specialities. We present the case of a 66-year-old female who was stabbed in the right posterior chest. CT revealed a diaphragmatic injury, liver laceration involving segments 6/7 with active bleeding, and a posterior superior mesenteric artery (SMA) to anterior inferior vena cava (IVC) fistula. Due to the proximity of the SMA injury to a replaced right hepatic artery origin, the fistulous connection with the suprarenal IVC, and suspected pancreatic and duodenal injuries, a hybrid rather than a purely endovascular approach was taken. A large compliant occlusion balloon was placed percutaneously in the hepatic IVC. Subsequent trauma laparotomy and right medial visceral rotation identified SMA and SMV injuries, which were repaired with temporary supracoeliac aortic clamping. Further kocherisation of the duodenum revealed a 10 cm longitudinal IVC laceration causing sudden large volume venous haemorrhage. This was repaired after control was gained with supracoeliac aortic clamping, infrarenal IVC vessel loop and balloon inflation. An abdominal VAC dressing was applied. Before transfer to ICU, however, 1L of blood was noted in the VAC cannister and a relook laparotomy demonstrated more than 1L of intrabdominal fresh blood. Bleeding vessels around the uncinate process were ligated. After 48 hours, a relook laparotomy revealed no significant bleeding, and the abdomen was closed. A post-operative MRCP demonstrated pancreatic divisum and likely laceration of the aberrant ventral duct. A subsequent peripancreatic collection was managed conservatively.

Tension hemothorax following endovascular thoracic aortic transection repair: case report

Thoracic aortic transection (TAT) is the second commonest cause of death from blunt trauma surpassed only by head injury and is associated with a mortality of 80% to 90%. The injury site is typically anteromedial at the aortic isthmus where differential shear forces act during rapid deceleration. The authors report a lateral aortic laceration managed by endovascular repair that required open thoracotomy for tension hemothorax resulting from an endoleak.

Subzero nonfreezing storage of the mammalian cardiac explant. I. Methanol, ethanol, ethylene glycol, and propylene glycol as colligative cryoprotectants

We employed hyperosmotic concentrations of penetrating cryoprotective agents (CPA) to store the isolated rat hearts unfrozen at subzero temperatures. The effect of acute exposure to CPA was assessed by flushing the hearts with CP-14, a cardioplegic solution, containing methanol (MeOH), ethanol (EtOH), ethylene glycol (EG), or propylene glycol (PG) for 2 min and reperfusing immediately with Krebs-Henseleit buffer in a working-heart model. The maximal doses that did not cause irreversible suppression of heart function were: MeOH, 1.78 M; EtOH, 1.27 M; EG, 0.84 M; and PG, 0.87 M. For nonfreezing storage, the hearts were flushed with CP-14 containing the highest tolerable concentrations of MeOH, EtOH, EG, or PG, stored for 6 h at -3.7, -2.8, and -1.4 degrees C, respectively, and then reperfused. Control cardiac output (CO) was 76.2 +/- 1.8 ml/min. Post-reperfusional recovery of CO was 86% in MeOH hearts, 82% in EtOH hearts, 76% in EG hearts, and 79% in PG hearts. Thus MeOH offered not only the least cardiac-suppressing effect but the lowest nonfreezing storage temperature. When storage time was extended, recovery and myocardial ATP level decreased with time in hearts flushed with CP-14 + 1.78 M MeOH and stored at -3.7 degrees C. The decay of function was faster than the decay of ATP level, suggesting energy was better preserved than function. The low return of function, however, may be related to CPA toxicity, osmotic stress, and ischemia/reperfusion injury. Nonfreezing storage at subzero temperatures using these CPAs may provide a novel approach to long-term cardiac preservation.

Freezing preservation of the mammalian cardiac explant. VI. Effect of thawing rate on functional recovery

This study investigated the effect of thawing rate on the preservation of frozen isolated rat hearts. The hearts were flushed with a hyperosmotic cardioplegic solution, CP-14/EtOH (1.15 Osm/kg), frozen at a rate of 0.18 degree C/hr for 6 h to -3.2 degrees C. Thereafter, the hearts were thawed at rates ranging from 0.08 to 1.1 degrees C/min for 1 to 14 min until the heart temperature reached -2.1 degrees C, the melting point (MP) of the flush solution; then they were held at -1 degree C for 11 to 24 min so that the total thaw time was 25 min. Post-thaw function was assessed by working reperfusion and expressed as percentage of unstored control function. Cardiac output (CO) and other hemodynamic performance showed biphasic responses to the thaw rate. At 0.08 degree C/min rate, CO recovered to 29.1 +/- 4.1 ml/min (40.8 +/- 5.8% of control). Thawing at 0.13 degree C/min enhanced the recovery of CO to 60.5 +/- 4.9%. Between 0.13 and 0.34 degree C/min, recovery was statistically insignificant. Faster thawing at 0.59 and 1.1 degrees C/min caused progressively less recovery. Overall, 0.13 degree C/min offered the highest recovery. In conclusion, function in slowly frozen heart is intimately affected by the thawing rate; there was an optimal intermediate thawing rate and both too slow and too fast thawing were detrimental.

Freezing preservation of the mammalian cardiac explant. V. Cryoprotection by ethanol

We studied the colligative cryoprotective effect of ethanol (EtOH) in preserving the isolated rat heart frozen at -3.4 degrees C or unfrozen at -1.4 degrees C. Addition of 4.7% (v/v) EtOH to a cardioplegic solution, CP-14, raised the osmolality from 280 to 1100 mOsm/kg H2O and lowered the melting point from -0.52 to -2.1 degrees C. Freezing of the cardiac explant at -3.4 degrees C for 6 h resulted in 34.3 +/- 1.9% of the tissue water as ice; recovery of cardiac output (CO) was 50%. Polyethylene glycol, which at 5% (w/v) has been shown to cryoprotect the hearts during freezing at -1.4 degrees C, did not improve the protective effect of 4.7% EtOH. CP-14 + 4.7% EtOH did not freeze at -1.4 degrees C. After 6 h storage, CO in hearts flushed with CP-14 + 4.7% EtOH oxygenated with 95% O2/5%CO2 returned to almost control level and was much higher than that in hearts flushed with 100% O2 saturated-CP-14 + 4.7% EtOH. Storage of 8 and 12 h reduced CO to 87 +/- 9 and 60 +/- 5% of control. By employing EtOH as a colligative cryoprotectant, we preserved the adult mammalian heart frozen at -3.4 degrees C or unfrozen at -1.4 degrees C, suggesting that this small molecular weight, penetrating substance may be a suitable cryoprotectant for long-term storage of the cardiac explant at high subzero temperatures.