Timing of elective surgery as a perioperative outcome variable: analysis of pancreaticoduodenectomy.

OBJECTIVES: The timing of major elective operations is a potentially important but rarely examined outcome variable. This study examined elective pancreaticoduodenectomy (PD) timing as a perioperative outcome variable. METHODS: Consecutive patients submitted to PD were identified. Determinants of 90-day morbidity (prospectively graded and tracked), anastomotic leak or fistula, and mortality, including operation start time (time of day), day of week and month, were assessed in univariate and multivariate analyses. Operation start time was analysed as a continuous and a categorical variable. RESULTS: Of the 819 patients identified, 405 (49.5%) experienced one or more complications (total number of events = 684); 90-day mortality was 3.5%. On multivariate analysis, predictors of any morbidity included male gender (P = 0.009) and estimated blood loss (P = 0.017). Male gender (P = 0.002), benign diagnosis (P = 0.002), presence of comorbidities (P = 0.002), American Society of Anesthesiologists (ASA) score (P = 0.025), larger tumour size (P = 0.013) and positive resection margin status (P = 0.005) were associated with the occurrence of anastomotic leak or fistula. Cardiac and pulmonary comorbidities were the only variables associated with 90-day mortality. Variables pertaining to procedure scheduling were not associated with perioperative morbidity or mortality. Operation start time was not significant when analysed as a continuous or a categorical variable, or when stratified by surgeon. CONCLUSIONS: Perioperative outcome after PD is determined by patient, disease and operative factors and does not appear to be influenced by procedure timing.

Management of hepatocellular adenoma: comparison of resection, embolization and observation.

INTRODUCTION: Hepatocellular adenoma (HA) is an uncommon benign hepatic tumour with the potential for malignant change or spontaneous haemorrhage. Resection has been the recommended treatment, but outcomes with other approaches are ill defined. METHODS: Demographic and outcomes data were retrospectively collected on patients diagnosed with HA at a tertiary hepatobiliary centre from 1992-2011 whom underwent resection, bland embolization or observation. RESULTS: In total, 52 patients with 100 adenomas were divided into single HA (n = 27), multiple HA (n = 18), and adenomatosis (n = 7) groups. Eighty-seven per cent were female and 37% had a history of hormone use. Median sizes of resected, embolized and observed adenomas were 3.6 cm, 2.6 cm and 1.2 cm, respectively. Forty-eight adenomas were resected as a result of suspicion of malignancy (39%) or large size (39%); 61% of these were solitary. Thirty-seven were embolized for suspicion of malignancy (56%) or hsemorrhage (20%); 92% of these were multifocal. Two out of three resected adenomas with malignancy were ≥10 cm and recurred locally [4%, confidence interval (CI) 1-14%]. Ninety-two per cent of the embolized adenomas were effectively treated; three persisted (8.1%, CI 2-22%). Most observed lesions did not change over time. CONCLUSIONS: While solitary adenomas are often resected, multifocal HAs are frequently embolized. Small adenomas can safely be observed. Given low recurrence rates, select HAs can be considered for embolization.

Anticoagulation dilemma in a high-risk patient with On-X valves.

Thromboembolism continues to be a major concern in patients with mechanical heart valves, especially in those with unsatisfactory anticoagulation levels. The new On-X valve (On-X Life Technologies, Austin, TX, USA) has been reported as having unique structural characteristics that offer lower thrombogenicity to the valve. We report a case where the patient received no or minimal systemic anticoagulation after placement of On-X mitral and aortic valves due to development of severe mucosal arterio-venous malformations yet did not show any evidence of thromboembolism. This case report reinforces the findings of recent studies that lower anticoagulation levels may be acceptable in patients with On-X valves and suggests this valve may be particularly useful in those in whom therapeutic levels of anticoagulation cannot be achieved due to increased risk of bleeding.

Intraoperative ultrasound and tissue elastography measurements do not predict the size of hepatic microwave ablations.

RATIONALE AND OBJECTIVES: Image-guided thermal ablation is used to treat primary and secondary liver cancers. Evaluating completeness of ablation is difficult with standard intraoperative B-mode ultrasound. This study evaluates the ability of B-mode ultrasound (US) and tissue elastography to adequately measure the extent of ablation compared to pathologic assessment. MATERIALS AND METHODS: An in vivo porcine model was used to compare B-mode ultrasonography and elastography to pathologic assessment of the microwave ablation zone area. In parallel, intraoperative ablations in patients were used to assess the ability of B-mode US and elastographic measures of tissue strain immediately after ablation to predict ablation size, compared to postprocedural computed tomography (CT). RESULTS: In the animal model, ablation zones appeared to decrease in size when monitored with ultrasound over a 10-minute span with both B-mode US and elastography. Both techniques estimated smaller zones than gross pathology, however, the differences did not reach statistical significance. Biopsies from the edges of the ablation zone, as assessed by US, contained viable tissue in 75% of the cases. In the human model, B-mode US and elastography estimated similar ablation sizes; however, they underestimate the final size of the ablation defect as measured on postprocedure CT scan (median area [interquartile range]: CT, 7.3 cm(2) [5.2-9.5] vs. US 3.6 cm(2) [1.7-6.3] and elastography 4.1 cm(2) [1.4-5.1]; P = .005). CONCLUSIONS: Ultrasound and elastography provide an accurate gross estimation of ablation zone size but are unable to predict the degree of cellular injury and significantly underestimate the ultimate size of the ablation.

Ablation of perivascular hepatic malignant tumors with irreversible electroporation.

BACKGROUND: Ablation is increasingly used to treat primary and secondary liver cancer. Ablation near portal pedicles and hepatic veins is challenging. Irreversible electroporation (IRE) is a new ablation technique that does not rely on heat and, in animals, appears to be safe and effective when applied near hepatic veins and portal pedicles. This study evaluated the safety and short-term outcomes of IRE to ablate perivascular malignant liver tumors. STUDY DESIGN: A retrospective review of patients treated with IRE between January 1, 2011 and November 2, 2011 was performed. Patients were selected for IRE when resection or thermal ablation was not indicated due to tumor location. Treatment outcomes were classified by local, regional, and systemic recurrence and complications. Local failure was defined as abnormal enhancement at the periphery of an ablation defect on post-procedure contrast imaging. RESULTS: Twenty-eight patients had 65 tumors treated. Twenty-two patients (79%) were treated via an open approach and 6 (21%) were treated percutaneously. Median tumor size was 1 cm (range 0.5 to 5 cm). Twenty-five tumors were <1 cm from a major hepatic vein; 16 were <1 cm from a major portal pedicle. Complications included 1 intraoperative arrhythmia and 1 postoperative portal vein thrombosis. Overall morbidity was 3%. There were no treatment-associated mortalities. At median follow-up of 6 months, there was 1 tumor with persistent disease (1.9%) and 3 tumors recurred locally (5.7%). CONCLUSIONS: This early analysis of IRE treatment of perivascular malignant hepatic tumors demonstrates safety for treating liver malignancies. Larger studies and longer follow-up are necessary to determine long-term efficacy.