Multi-detector computed tomography in coronary artery bypass graft assessment: a meta-analysis

Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures.     

Endogenous tyrosine hydroxylase activity in the developing chick heart: a possible source of extraneuronal catecholamines

The source of catecholamines in the developing chick heart was investigated by using catecholamine assays and tyrosine hydroxylase assays on hearts from normal and chemically-sympathectomized chick embryos. A biochemical index of sympathetic nerve development in the heart was obtained by monitoring the ability of sympathetic nerves in the atria to take up [3H]-norepinephrine in vitro. Specific neuronal uptake of [3H]-norepinephrine in atria was first detected on incubation day 11 and increased throughout the incubation period. High performance liquid chromatography with electrochemical detection was used to measure the norepinephrine concentration and content of embryonic hearts. The cardiac norepinephrine concentration fluctuated throughout the incubation period but was particularly low (0.01 +/- 0.005 ng/mg wet wt) on incubation days 10 to 13, coincident with the arrival of sympathetic nerves in the heart. The highest norepinephrine concentration was measured on incubation day 7 (2.09 +/- 0.50 ng/mg wet wt) prior to the arrival of sympathetic nerves in the heart. Sympathetic nerve axotomy produced by chronic treatment with 6-hydroxydopamine reduced [3H]-norepinephrine uptake in atria and norepinephrine concentration in whole hearts on incubation day 20 to 33 and 47% of control, respectively. Tyrosine hydroxylase activity was detected in normal hearts on incubation day 7, 3 to 4 days before the heart is innervated by sympathetic nerves. Tyrosine hydroxylase activity persisted in the heart on incubation day 20, despite treatment with 6-hydroxydopamine on incubation days 13 to 19. The tyrosine hydroxylase activity in 6-hydroxydopamine lesioned hearts was not significantly different from saline-treated controls. This data indicates that tyrosine hydroxylase activity is present in the immature chick heart prior to the arrival of sympathetic innervation and following chemical sympathectomy; hence, an extraneuronal source of tyrosine hydroxylase, the rate limiting enzyme for catecholamine biosynthesis, exists in the embryonic chick heart.     

Axillary lymph node status,but not tumor size,predicts locoregional recurrence and overall survival after mastectomy for breast cancer

OBJECTIVE: To assess the significance of axillary lymph node status and tumor size for predicting locoregional recurrence (LRR) and overall survival after mastectomy for breast cancer and to discuss the utility of postmastectomy radiation therapy. SUMMARY BACKGROUND DATA: Patients with locally advanced breast cancer require multimodality treatment combining chemotherapy (and/or hormonal therapy), surgery, and radiation. Randomized trials have demonstrated that postmastectomy radiation reduces LRR, but no overall survival benefit has been established. METHODS: Criteria for accrual to the Alabama Breast Cancer Project (1975-1978) were female gender and T2-3 breast cancer with M0 status. Patients underwent a radical or a modified radical mastectomy. Node-positive patients received adjuvant cyclophosphamide, methotrexate, and fluorouracil chemotherapy or adjuvant melphalan. Patients were evaluated for LRR and overall survival based on the number of positive axillary lymph nodes and (in N0 patients) pathologic tumor size. Significance was determined using chi-square analysis. Survival curves were generated using the Kaplan-Meier method and were compared by log-rank analysis. RESULTS: After median follow-up of 15 years, neither type of surgery nor chemotherapy was shown to affect locoregional disease-free or overall survival. LRR rates were higher and overall survival rates were lower in patients with nodal involvement, while tumor size was not shown to significantly affect these rates. CONCLUSIONS: Patients with axillary lymph node metastases may benefit from postmastectomy radiation, but the use of postmastectomy radiation in N0 patients is not supported when it is based on tumor size alone.     

Cytokines and growth factors in keratinocytes and sweat glands in chronic venous leg ulcers. An immunohistochemical study

The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing.     

Results of long-term follow-up for transanal excision for rectal cancer

Low anterior resection and abdominoperineal resection are the surgical techniques used most frequently in the treatment of rectal cancer. It is our hypothesis that selected patients with early T stage, well or moderate grade of differentiation, and small tumor size are good candidates for transanal excision in terms of minimal morbidity, low recurrence rate, and sphincter preservation. From January 1993 until August 2001 30 patients underwent transanal excision; three patients were excluded because they had histology other than adenocarcinoma. Factors analyzed included those related to the patient [age (years), gender, race, body mass index, and anal tone], tumor [size (cm), distance from the anal verge (cm), differentiation, and American Joint Committee on Cancer stage], and additional treatment. Median follow-up of the group was 40.7 months (range 0.6-99) and the primary end points were local and distant recurrence. Data are presented as mean (range). The median age of the group was 58.9 years (range 27-94); 52 per cent were female and 48 per cent were male. The mean body mass index was 25.9 (range 22.7-36.7). Preoperatively 81, 11, and 4 per cent of the patients had stage I, II, and III/IV cancer, respectively. Preoperative size of the tumor was 2.0 cm (1-3 cm), and distance from the anal verge was 5.0 cm (3-15 cm). Blood loss was 50 cm3 (5-200 cm3), and there were no operative complications. Tumor differentiation levels were well (37%) and moderate (63%). All patients had negative margins. Additional treatment consisted of radiation therapy in seven patients (six postoperative and one preoperative). Chemotherapy was given to seven patients (six postoperative and one preoperative). The local recurrence rate was 7.4 per cent (two patients), and 3.7 per cent recurred distantly (one patient). Transanal excision of low rectal cancer in selected patients is an acceptable alternative to formal resection. Important selection criteria include early T stage, well or moderate differentiation, relatively small tumor size, and negative microscopic margins. The roles of radiation and chemotherapy remain controversial.     

Arteriovenous malformation mimicking a renal-cell carcinoma

We describe a renal arteriovenous malformation in a patient with a 1-month history of flank pain. Imaging studies were interpreted as being consistent with renal-cell carcinoma. However, Doppler ultrasonography demonstrated turbulent blood flow, and selective renal angiography confirmed the diagnosis of an arteriovenous malformation. Embolization relieved the pain. This case calls attention to the need to consider arteriovenous malformations in the differential diagnosis of central homogenously enhancing renal lesions.     

Right hemicolectomy anastomotic leak study: a review of right hemicolectomy in the binational clinical outcomes registry (BCOR)

Backgrounds

Surgery remains mainstay management for colon cancer. Post-operative anastomotic leak (AL) carries significant morbidity and mortality. Rates of, and risk factors associated with AL following right hemicolectomy remain poorly documented across Australia and New Zealand. This study examines the Bowel Cancer Outcomes Registry (BCOR) to address this.

Methods

A retrospective cohort study was undertaken of consecutive BCOR-registered right hemicolectomy patients undergoing resection for colon cancer (2007–2021). The primary outcome measure was AL incidence. Clinicopathological data were extracted from the BCOR. Factors associated with AL and primary anastomosis were identified using logistic regression. AL-rate trends were assessed by linear regression.

Results

Of 13 512 patients who had a right hemicolectomy (45.2% male, mean age 72.5 years, SD 12.1), 258 (2.0%) had an AL. On multivariate analysis, male sex (OR 1.33; 95% CI 1.03–1.71) and emergency surgery (OR 1.41; 95% CI 1.04–1.92) were associated with AL. Private health insurance status (OR 0.66; 95% CI 0.50–0.88) and minimally-invasive surgery (OR 0.61; 95% CI 0.47–0.79) were protective for AL. Anastomotic technique (handsewn versus stapled) was not associated with AL (P = 0.84). Patients with higher ASA status (OR 0.47; 95% CI 0.39–0.58), advanced tumour stage (OR 0.56; 95% CI 0.50–0.63), and emergency surgery (OR 0.16; 95% CI 0.13–0.20) were less likely to have a primary anastomosis. AL-rate and year of surgery showed no association (P = 0.521).

Conclusion

The AL rate in Australia and New Zealand following right hemicolectomy is consistent with the published literature and was stable throughout the study period. Sex, emergency surgery, insurance status, and minimally invasive surgery are associated with AL incidence.     

Pilot study of a novel pain management strategy: evaluating the impact on patient outcomes

Background

Our objective was to evaluate the impact of a novel multimodal pain management strategy on intraoperative opioid requirements, postoperative pain, narcotic use, and length of stay.

Methods

Consecutive patients undergoing elective laparoscopic colorectal resection were managed with an experimental protocol. The protocol uses a post-induction, pre-incision bilateral TAP block and local peritoneal infiltration at port sites with long-acting liposomal bupivacaine (20 mL long-acting liposomal bupivacaine, 30 mL 0.25 % bupivacaine, 30 mL saline). Experimental patients were matched on age, body mass index, gender, comorbidity, diagnosis, and procedure to a control group that received no block or local wound infiltration. Both groups followed a standardized enhanced recovery pathway. Demographics, perioperative, and postoperative outcomes were evaluated. The main outcome measures were intraoperative opioids, postoperative pain, opioid use, and length of stay.

Results

Fifty patients were analyzed—25 experimental and 25 controls. Patients were well matched on all demographics. In both cohorts, the main diagnosis was colorectal cancer and primary procedure performed a segmental resection. Operative times were similar (p = 0.41). Experimental patients received significantly less intraoperative fentanyl (mean 158 mcg experimental vs. 299 mcg control; p < 0.01). The experimental group had significantly lower initial (p < 0.01) and final PACU pain scores (p = 0.04) and shorter LOS (3.0 vs. 4.1 days, p = 0.04) compared to controls. Experimental patients trended toward shorter PACU times and lower opioid use and daily pain scores throughout the hospital stay. Postoperative complication and readmission rates were similar across groups. There were no reoperations or mortality.

Conclusions

Our multimodal pain management strategy reduced intraoperative opioid administration. Postoperatively, improvements in PACU time, postoperative pain and narcotic use, and lengths of stay were seen in the experimental cohort. With the favorable finding from the pilot study, further investigation is warranted to fully evaluate the impact of this pain management protocol on patient satisfaction, clinical and financial outcomes.

     

The Hemodynamic Mechanisms of Lung Injury and Systemic Inflammatory Response Following Brain Death in the Transplant Donor

Brain-dead donors are the major source of lungs for transplantation. Brain death is characterized by two hemodynamic phases. Initially, massive sympathetic discharge results in a hypertensive crisis. This is followed by neurogenic hypotension. Up-regulation of pro-inflammatory mediators occurs in all organs and lung injury develops; this can adversely affect graft function post-transplantation. The mechanisms of the systemic and lung inflammation are unknown. We hypothesized that the hemodynamic changes are responsible for these inflammatory phenomena. Brain death was induced by intra-cranial balloon inflation in rats. This resulted in hypertensive crisis, followed by hypotension. There was a significant increase in blood neutrophil CD11b/CD18 expression and pro-inflammatory cytokine levels in serum and bronchoalveolar lavage, compared with control animals. Rupture of the capillary-alveolar membrane was demonstrated by electron microscopy. Elimination of the hypertensive response by α-adrenergic antagonist pre-treatment prevented inflammatory lung injury, reduced the systemic inflammatory markers and preserved capillary-alveolar membrane integrity. Correction of the neurogenic hypotension with noradrenaline ameliorated the systemic inflammatory response and improved oxygenation. We conclude that the sympathetic discharge triggers systemic and lung inflammation, which can be further enhanced by neurogenic hypotension. Management of the brain-dead donor with early anti-inflammatory treatment and vasoconstrictors is warranted.