Pilot Study to Optimize Goal-directed Hemodynamic Management During Pancreatectomy.

INTRODUCTION: Intraoperative goal-directed hemodynamic therapy (GDHT) is a cornerstone of enhanced recovery protocols. We hypothesized that use of an advanced noninvasive intraoperative hemodynamic monitoring system to guide GDHT may decrease intraoperative hypotension (IOH) and improve perfusion during pancreatic resection. METHODS: The monitor uses machine learning to produce the Hypotension Prediction Index to predict hypotensive episodes. A clinical decision-making algorithm uses the Hypotension Prediction Index and hemodynamic data to guide intraoperative fluid versus pressor management. Pre-implementation (PRE), patients were placed on the monitor and managed per usual. Post-implementation (POST), anesthesia teams were educated on the algorithm and asked to use the GDHT guidelines. Hemodynamic data points were collected every 20 s (8942 PRE and 26,638 POST measurements). We compared IOH (mean arterial pressure <65 mmHg), cardiac index >2, and stroke volume variation <12 between the two groups. RESULTS: 10 patients were in the PRE and 24 in the POST groups. In the POST group, there were fewer minimally invasive resections (4.2% versus 30.0%, P = 0.07), more pancreaticoduodenectomies (75.0% versus 20.0%, P < 0.01), and longer operative times (329.0 + 108.2 min versus 225.1 + 92.8 min, P = 0.01). After implementation, hemodynamic parameters improved. There was a 33.3% reduction in IOH (5.2% ± 0.1% versus 7.8% ± 0.3%, P < 0.01, a 31.6% increase in cardiac index >2.0 (83.7% + 0.2% versus 63.6% + 0.5%, P < 0.01), and a 37.6% increase in stroke volume variation <12 (73.2% + 0.3% versus 53.2% + 0.5%, P < 0.01). CONCLUSIONS: Advanced intraoperative hemodynamic monitoring to predict IOH combined with a clinical decision-making tree for GDHT may improve intraoperative hemodynamic parameters during pancreatectomy. This warrants further investigation in larger studies.

Dynamic adaptation of liver mitochondria to chronic alcohol feeding in mice: biogenesis, remodeling, and functional alterations.

Liver mitochondria undergo dynamic alterations following chronic alcohol feeding to mice. Intragastric alcohol feeding to mice resulted in 1) increased state III respiration (109% compared with control) in isolated liver mitochondria, probably due to increased levels of complexes I, IV, and V being incorporated into the respiratory chain; 2) increased mitochondrial NAD(+) and NADH levels (∼2-fold), with no change in the redox status; 3) alteration in mitochondrial morphology, with increased numbers of elongated mitochondria; and 4) enhanced mitochondrial biogenesis in the liver, which corresponded with an up-regulation of PGC-1α (peroxisome proliferator-activated receptor γ coactivator-1α). Oral alcohol feeding to mice, which is associated with less liver injury and steatosis, slightly enhanced respiration in isolated liver mitochondria (30.8% compared with control), lower than the striking increase caused by intragastric alcohol feeding. Mitochondrial respiration increased with both oral and intragastric alcohol feeding despite extensive N-acetylation of mitochondrial proteins. The alcohol-induced mitochondrial alterations are probably an adaptive response to enhance alcohol metabolism in the liver. Isolated liver mitochondria from alcohol-treated mice had a greater rate of acetaldehyde metabolism and respiration when treated with acetaldehyde than control. Aldehyde dehydrogenase-2 levels were unaltered in response to alcohol, suggesting that the greater acetaldehyde metabolism by isolated mitochondria from alcohol-treated mice was due to increased mitochondrial respiration that regenerated NAD(+), the rate-limiting substrate in alcohol/acetaldehyde metabolism. Overall, our work suggests that mitochondrial plasticity in the liver may be an important adaptive response to the metabolic stress caused by alcohol intake and could potentially play a role in many other vital functions performed by the liver.

Peri-Hilar Cystic Lymphangioma Mimicking a Biliary Cystic Lesion Causing Biliary Obstruction: A Case Report and Literature Review.

BACKGROUND Lymphangiomas are rare and benign malformations of the lymphatic system. The presentation of intra-abdominal lymphangiomas, especially from within the hepatoduodenal ligament, is rare in the adult population. In this report, we examine a lymphangioma within the hepatoduodenal ligament resulting in biliary obstruction. CASE REPORT A 62-year-old man with surgical history of cholecystectomy presented to the hepatobiliary clinic for a peri-hilar cystic lesion identified on surveillance magnetic resonance imaging (MRI). The patient's MRI revealed a 5.5-cm cystic lesion at the peri-hilar region, likely arising from the biliary tree, which had been increasing in size and causing biliary dilatation. The patient underwent an endoscopic ultrasound, showing a 4.3×2.2 cm cystic structure likley arising from the cystic duct stump with internal septation. An endoscopic retrograde cholangiopancreatography (ERCP) was performed and demonstrated no communication between the biliary tree and the cystic lesion. Given the uncertain etiology of the lesion and its obstructive nature, the patient was moved to the operating room for a complete excision. A well-encapsulated cystic lesion was identified between the cystic duct and the common hepatic duct, which did not communicate with the biliary tree. Pathology confirmed the diagnosis of lymphangioma with features of vascular channel proliferation in the background of fibrotic stroma and lymphoid aggregates. The vascular channel proliferation demonstrated positive immunohistochemical staining for D2-40. At 3-year follow-up, there was no evidence of post-resection recurrence. CONCLUSIONS This case represents an acquired lymphangioma occurring as a sequela of cholecystectomy, likely caused by interruption of the lymphatic drainage system secondary to surgical manipulation.

Perivascular epithelioid cell tumour-mimicking retroperitoneal leiomyosarcoma.

A young man in his 40s was evaluated in the emergency department for abdominal and right flank pain. A CT scan of the abdomen and pelvis showed a solid, well-circumscribed lesion measuring 7.1×8.1×5.4 cm, which was arising from the retroperitoneum and extending from the third portion of the duodenum towards the right kidney. A percutaneous core biopsy was obtained, demonstrating an atypical smooth muscle neoplasm suggestive of a low-grade leiomyosarcoma. The patient underwent surgery for an en-block resection of the mass and the final pathology confirmed a perivascular epithelioid cell neoplasm without significant pleomorphism, mitosis or necrosis. Our case adds to the small number of perivascular epithelioid cell tumour cases reported in the literature and we present it in order to increase our understanding of this tumour and to assist in its appropriate diagnosis and management.

Retrievable inferior vena cava filters in geriatric trauma: Is there an age bias?

BACKGROUND: Trauma patients are at increased risk for developing venous thromboembolic (VTE) disease. The EAST (Eastern Association for the Surgery of Trauma) practice management guidelines identified risk factors for VTE, as well as indications for prophylactic inferior vena cava filters (IVCF). In a 2009 study, our institution found a 26% retrieval rate for IVCF. Lack of retrieval was most consistently due to lack of follow-up. Our study is a follow-up analysis for retrieval rate of IVCF, since the formation of a geriatric trauma service. We anticipated that geriatric trauma patients would have a lower rate of IVCF retrieval compared to the general trauma patient. METHODS: Our study population consisted of trauma patients admitted from January 2008 to August 2013, with documented VTE or high risk for VTE with contraindication to anticoagulation. INCLUSION CRITERIA: IVCF placed in trauma patients. EXCLUSION CRITERIA: permanent filters, retrievable filters placed permanently, non-trauma patients, superior vena cava filters and patients who died before discharge. RESULTS: During the study period, 160 trauma patients had an IVCF placed, of which 147 survived and were discharged. Of those patients, 66% (97/147) were planned for retrieval. Overall, the retrieval rate was 34% (33/97). Following age categorization, rates were 47% (30/64) and 9% (3/33) for those <65 and >/=65 years old, respectively. Applying Fisher's Exact Test to a crosstab of planned retrieval by age category yielded a statistically significant difference, p<0.0005 at alpha=0.05. In the geriatric population with IVCFs not retrieved, 23% (7/30) died and 67% (20/30) were lost to follow-up. CONCLUSION: IVCF plays a critical role in the management of trauma patients with VTE, particularly the geriatric population. Since our 2009 study, we have improved nearly ten percentage points (26% to 34%); however, we exposed an age bias with retrieval rate being lower in patients >/=65 compared to those <65 (9% vs. 47%).