ACUTE MESENTERIC ISCHÆMIA

The experience of acute mesenteric ischæmia at St Vincent's Hospital, Melbourne, has been reviewed over 17 years. The mortality remains appallingly high. This applies particularly to those patients who had thrombosis of the superior mesenteric artery, amongst whom the mortality in this series was 97%. The mortality was slightly less in the group suffering from embolic occlusion of the superior mesenteric artery (66%), and in those suffering from thrombosis of the superior mesenteric vein (60%). A mortality of 66% was also found in patients suffering from non-occlusive gut ischæmia. Delay in diagnosis accounted for this high mortality. Early diagnosis is all-important, and this depends on the performance of mesenteric angiography in any patient suspected of having mesenteric ischæmia. Appropriate surgery may then be carried out in the occlusive group and supportive treatment, including intraarterial papaverine infusion, given to those with non-occlusive ischæmia. There is a pressing need for simple non-invasive tests to segregate those patients suffering from acute mesenteric ischæmia from those whose acute abdomen is due to some other cause.     

AN OVERVIEW OF CARDIAC SURGERY

The scope of cardiac surgery has extended greatly in the last decade, advances being particularly in the areas of perfusion technology, ischæmic heart disease, and congenital defects in the infant. This paper sets out to summarize accepted current practice in the surgery of the heart and great vessels. Principles have been emphasized at the expense of detail, since the aim has been to present information which might be of interest to surgeons in general. Some aspects which have a special relevance to general surgical practice have been grouped separately for the sake of emphasis.     

RENAL ANGIOGRAPHY AND THE MANAGEMENT OF SEVERE CLOSED RENAL TRAUMA1

The purpose of this study was to determine the place of selective renal angiography in the assessment of major renal trauma. Thirty-one cases of renal injury assessed by urography and angiography were reviewed, and the radiological features correlated with the subsequent clinical course. Based on the angiographic findings, a classification of these more severe injuries is proposed, and the prognostic significance of renal ischæmia demonstrated. Because conservative treatment in those cases with significant ischæmia is likely to fail, early elective surgery is recommended. In this selected group, viable renal tissue can be preserved, and the necessity for subsequent nephrectomy due to secondary hæmorrhage, or continuing urine leakage, is avoided.     

A Comparison of Perfusates for 24-Hour Preservation of Ischæmically Damaged Canine Kidneys

A comparison is made of the efficacies of three solutions for brief perfusion of ischæmically damaged canine kidneys before 24 hours' preservation in ice and autotransplantation. Perfusion with a plasma-red-cell mixture, with intracellular electrolyte solution (Collins C₃), mid perfusion with an extracellular “electrolyte solution” all gave comparable results, similar to those in a control group with no perfusion.     

Anæmia and Surgery: A Retrospective Clinical Study

A study has been made comparing the surgical performances of 145 anæmic patients who had hæmoglobin levels below 10 gm/100 ml of blood with the surgical performances of 412 routine surgical cases. While there appeared to be an apparent increase in cardiac arrests or deaths during surgery or in the early postoperative period in the anæmic cases, it is doubtful whether this is significant. Other surgical or postoperative complications did not appear to occur more frequently in the anæmic cases than in the controls, nor did the complications in the anæmic patients require treatment not given to patients in the control series.     

CLAUDICATION OF THE CAUDA EQUINA

The term “claudication of the cauda equina” is examined. It has arisen from semantic errors, and a belief in ischæmia for which there is no scientific evidence. Its use tends to hamper rather than assist the investigation of patients with obscure pain in the lower limb. A preferable alternative term, “atypical sciatica”, is suggested.     

The Influence of Technical Factors upon Renal Homograft Function1

Though immunological rejection is the chief obstacle to the prolonged survival of renal homografts, a significant number of graft failures can be attributed to complications of surgical technique. The purpose of this paper is to analyse the influence of vascular anomalies in the donor kidney upon graft function. Factors considered include the duration of “warm” and “cold” ischæmia, the technical improvisation of the vascular anastomoses, and the utilization of both kidneys from any cadaver. During the past three and a half years, 43 renal homografts have been transplanted into 40 patients at the Prince Henry Hospital, Sydney. Although there has been a high incidence of vascular anomaly in this series, no donor kidney has been discarded for this reason, and satisfactory graft function has been obtained in 31 of the transplanted kidneys.     

RECONSTRUCTION OF VERTEBRAL ARTERY STENOSIS1

Eight patients with transient attacks of cerebrovascular insufficiency were treated by reconstruction of an atheromatous stenosis at the origin of a vertebral artery. The technique was relatively simple and safe, and was effective in relieving symptoms. Previous reviews suggest that the symptoms of vertebrobasilar insufficiency tend to be persistent, frequent and distressing, and that they can be a prelude to brain stem infarction. The collateral circulation to the vertebrobasilar system may be restricted by anatomical variations and by disease, particularly affecting the circle of Willis. Bilateral vertebral artery disease can cause appreciable ischæmia even without associated carotid artery disease. Carotid endarterectomy is not particularly effective in relieving vertebrobasilar symptoms. Vertebral artery reconstruction appears to be the appropriate treatment for vertebrobasilar insufficiency.     

胃肠道脂肪瘤及其并发症MSCT表现

目的探讨胃肠道脂肪瘤及其并发症的MSCT表现。方法回顾性分析258例MSCT检查发现胃肠道脂肪瘤患者的临床、病理及影像学资料,患者均接受MSCT平扫+增强扫描。结果258例中,单发230例(230/258,89.15%),多发28例(28/258,10.85%),共发现脂肪瘤296个。单发肿瘤以空肠近段最常见(81/230,35.39%),其次是十二指肠(69/230,30.00%),直肠最少(1/230,0.43%)。病变体积0.000 9~198.59cm~3,中位数[0.71(0.31,1.75)]cm~3。肿瘤CT值-258~-35HU,增强扫描均无强化。296个脂肪瘤中,圆形147个(147/296,49.66%),椭圆形111个(111/296,37.50%),不规则形17个(17/296,5.74%),条状20个(20/296,6.76%),锥形1个(1/296,0.34%)。肿瘤并发肠梗阻18例(18/258,6.98%),其中重度梗阻6例,中度5例,轻度7例。并发肠梗阻、并发肠套叠及无并发症的脂肪瘤体积分别为(55.22±20.64)cm~3、(20.54±16.22)cm~3和(11.24±8.97)cm~3(F=140.200,P0.001)。结论胃肠道脂肪瘤体积和CT值可能是引起继发性肠套叠和肠梗阻的主要风险因素。MSCT能准确评估胃肠道脂肪瘤及其并发症。     

Ileosigmoid Knot at Week 13 of Pregnancy: Report of a Case

The ileosigmoid knot (ISK) is a rare cause of intestinal obstruction. ISK is a condition in which the ileum wraps around the base of the sigmoid colon and forms a knot, leading to high mortality with rapid progression to bowel gangrene. We herein report a rare case of ISK at week 13 of pregnancy. The ISK was diagnosed by computed tomography, and the patient underwent emergency surgery for acute abdomen. Laparotomy showed segmental gangrenous change in the sigmoid colon, which was twisted around the distal ileal loop. The gangrenous bowel was resected, and primary anastomosis was performed. To our knowledge, the present case involves the first and earliest pregnancy in which a preoperative diagnosis of ISK was made and successful treatment was performed with surgery. A radiologic approach should be undertaken for prompt diagnosis and optimal management, even in early pregnancy.Key words: Ileosigmoid knot, Pregnancy, Emergency surgery, Strangulation, Small bowel obstructionThe ileosigmoid knot (ISK) is a rare cause of intestinal obstruction. ISK is characterized by wrapping of the ileum around the base of the sigmoid colon, forming a mechanical bowel obstruction with rapid progression to bowel gangrene. ISK is associated with 0.5% to 1.7% of intestinal obstructions, and the reported mortality rate varies from 0% to 48% (mean, 35.5%).^1–3 The mortality rate of ISK with bowel gangrene is reportedly as high as 20% to 100%.³ Because the knot involving the ileum and sigmoid colon can be difficult to untie, this condition usually requires laparotomy. We experienced a rare case of ISK in a patient in early pregnancy who underwent emergency surgery for acute abdomen.     

Identification of a Linkage Disequilibrium Block in Chromosome 1q Associated With BMD in Premenopausal White Women

Osteoporosis is a complex disease with both genetic and environmental risk factors. A major determinant of osteoporotic fractures is peak BMD obtained during young adulthood. We previously reported linkage of chromosome 1q (LOD = 4.3) with variation in spinal areal BMD in healthy premenopausal white women. In this study, we used a two‐stage genotyping approach to identify genes in the linked region that contributed to the variation of femoral neck and lumbar spine areal BMD. In the first stage, 654 SNPs across the linked region were genotyped in a sample of 1309 premenopausal white women. The most significant evidence of association for lumbar spine (p = 1.3 × 10^?6) was found with rs1127091 in the GATAD2B gene. In the second stage, 52 SNPs around this candidate gene were genotyped in an expanded sample of 1692 white women. Significant evidence of association with spinal BMD (p < 10^?5), and to a lesser extent with femoral neck BMD, was observed with eight SNPs within a single 230‐kb linkage disequilibrium (LD) block. The most significant SNP (p = 3.4 × 10^?7) accounted for >2.5% of the variation in spinal BMD in these women. The 230‐kb LD block contains 11 genes, but because of the extensive LD, the specific gene(s) contributing to the variation in BMD could not be determined. In conclusion, the significant association between spinal BMD and SNPs in the 230‐kb LD block in chromosome 1q indicates that genetic factor(s) in this block plays an important role in peak spinal BMD in healthy premenopausal white women.     

Selective laser melting‐produced porous titanium scaffolds regenerate bone in critical size cortical bone defects

Porous titanium scaffolds have good mechanical properties that make them an interesting bone substitute material for large bone defects. These scaffolds can be produced with selective laser melting, which has the advantage of tailoring the structure's architecture. Reducing the strut size reduces the stiffness of the structure and may have a positive effect on bone formation. Two scaffolds with struts of 120‐µm (titanium‐120) or 230‐µm (titanium‐230) were studied in a load‐bearing critical femoral bone defect in rats. The defect was stabilized with an internal plate and treated with titanium‐120, titanium‐230, or left empty. In vivo micro‐CT scans at 4, 8, and 12 weeks showed more bone in the defects treated with scaffolds. Finally, 18.4 ± 7.1 mm³ (titanium‐120, p = 0.015) and 18.7 ± 8.0 mm³ (titanium‐230, p = 0.012) of bone was formed in those defects, significantly more than in the empty defects (5.8 ± 5.1 mm³). Bending tests on the excised femurs after 12 weeks showed that the fusion strength reached 62% (titanium‐120) and 45% (titanium‐230) of the intact contralateral femurs, but there was no significant difference between the two scaffolds. This study showed that in addition to adequate mechanical support, porous titanium scaffolds facilitate bone formation, which results in high mechanical integrity of the treated large bone defects. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 792–799, 2013     

Ischaemic optic neuropathy after spinal fusion

Purpose

We report a case of ischaemic optic neuropathy which occurred after prolonged spine surgery in the prone position in an obese, diabetic patient.

Clinical features

The patient was a 44-yr-old, 123 kg, 183 cm man for decompressive laminectomy and instrumented fusion of the lumbar spine. Anaesthesia was induced with thiopentone, fentanyl and succinylcholine and maintained with nitrous oxide, oxygen, isoflurane and a fentanyl infusion. He was positioned prone on the Relton-Hall frame and had an uneventful intraoperative course. Estimated blood loss was 3,000 ml. He was taken to the surgical intensive care unit (SICU) and the trachea was extubated 3.5 hr later. He had no pulmonary or haemodynamic problems and went to a regular nursing floor in the morning. He was discharged home on postoperative day #5. He telephoned his surgeon on postoperative day #7 to say that his vision had been blurry since surgery. His visual acuity was decreased, and on examination, he had a bilateral papillary defect, optic swelling and a splinter haemorrhage in the right eye. Magnetic resonance imaging (MRI) scan of the head and orbits detected no other abnormality. Based on this examination, he was felt to have bilateral ischaemic optic neuropathy and treated conservatively. By postoperative day #47, his visual acuity was greatly improved and near normal. Careful review of possible contributing factors suggests that the cause of the ischaemic optic neuropathy was venous engorgement.

Conclusion

This patient developed ischaemic optic neuropathy from a prolonged interval in the prone position of the Relton-Hall frame, which may be related to venous engorgement.

Objectif

Nous rapportons un cas de neuropathie optique ischémique consécutive à une chirurgie rachidienne prolongée en décubitus ventral chez un obèse diabétique.

Éléments cliniques

Un patient de 44 ans, pesant 123 kg et mesurant 183 cm était opéré pour une laminectomie décompressive avec ostéosynthèse instrumentale de la colonne lombaire. Le thiopental associé à du fentanyl et de la succinylcholine a servi à induire l’anesthésie, qui a été entretenue avec du protoxyde d’azote, de l’oxygène, de l’isoflurane et une perfusion de fentanyl. Il était immobilisé en décubitus ventral sur un cadre de Relton-Hall et l’opération s’est déroulée sans incident. On a estimé la perte sanguine à 3000 ml. Il a été transféré à l’unité des soins intensifs (USI) et extubé 3,5 h plus tard. Il ne présentait aucun problème respiratoire et hémodynamique et on l’a ramené dans son unité de soins le lendemain matin. Il était libéré le cinquième jour. Par téléphone, il avisait son chirurgien le septième jour que sa vision était embrouillée depuis l’intervention. Son acuité visuelle avait diminué et à l’examen, il présentait une lésion papillaire bilatérale, de l’oedème du nerf optique et une hémorragie linéaire de l’oeil droit. L’imagerie par résonance magnétique de la tête et des orbites ne montrait aucune autre anomalie. Cet examen suggérait une neuropathie optique ischémique bilatérale qui fut traitée de façon conservatrice. Le 47^e jour postopératoire, son acuité visuelle s’était améliorée considérablement et était presque redevenue normale. Parmi les facteurs contributoires possibles cette neuropathie ischémique, il faut retenir l’engorgement veineux.

Conclusion

À la suite d’une immobilisation prolongée en décubitus ventral sur un cadre de Relton-Hall, ce patient a présenté une neuropathie optique par ischémie causée vraisemblablement par engorgement veineux.     

Supraceliac aortic occlusion: A safe approach to pararenal aortic aneurysms

Twenty-four patients who underwent surgery for pararenal aortic aneurysms between January 1992 and April 1997 are reviewed. Eighteen patients had primary atherosclerotic aneurysms, three patients had symptomatic infected aneurysms, two patients had an aneurysm proximal to a prior aortic repair, and one patient had a pseudoaneurysm of a proximal aortic graft anastomosis. Thirteen patients underwent elective operation, five had an urgent operation, and six patients underwent an emergency procedure. Five patients had the proximal aortic clamp placed between the renal arteries (Group I), three patients had it placed between the superior mesenteric and the renal arteries (Group II), and 16 patients had it placed in a supraceliac location (Group III). Aneurysm size, age, sex, preoperative blood chemistries (including hemoglobin, hematocrit, liver function studies, and coagulation studies) were similar in all groups. Two patients in Group III were on hemodialysis preoperatively. Preoperative renal function (blood urea nitrogen and creatinine) was the same in all groups. Visceral ischémic time was 43.4 ± 9.37 min to the distal kidney in Group I, 26.6 ± 7.63 min in Group II, and 24.5 ± 6.22 min in Group III. Mean transfusion requirements were similar in all groups. Two patients in Group I required postoperative hemodialysis. No patient in either Group II or III developed renal insufficiency. Mortality was the same in each group but was related to the urgency of operation (elective 7.6%, urgent 40%, emergent 50%). Intrarenal clamping (Group I) was associated with more renal and gastrointestinal complications than either suprarenal or supraceliac clamping. Although suprarenal and supraceliac clamping had similar results, our preference is supraceliac clamping because it is technically easy to achieve and is associated with few end-organ complications.     

Pediatric surgery workforce: population and economic issues

Background

Whether a shortage of pediatric surgeons exists in the United States, such as those observed in the total physician and general surgical workforces, is an important issue that will affect decisions regarding training, credentialing, and reimbursement. Our goal was to update information regarding the demand and supply of pediatric surgeons.

Methods

Online American Pediatric Surgical Association (APSA) membership directory gave numbers of pediatric surgeons and their residence by metropolitan statistical areas (MSA), defined by the US census. Population and economic data were obtained from appropriate US government agencies.

Results

There were 835 APSA members and 375 MSA. Eliminated were 86 MSA (with 12 APSA members) with incomplete data, 14 MSA (0 members) with populations less than 100,000, and 25 members with listed locations outside an MSA. The remaining 798 members and 275 MSA comprised the study. The number of APSA members in an MSA correlated closely with MSA population (R² = 0.836) and 2006 births (R² = 0.767). Metropolitan statistical areas without an APSA member had a smaller population and birth rate than those with one or more members (P = .0001). An MSA with 1 APSA member had a higher population (P = .0003) and births per APSA member ratios (P = .0014) than MSA with 2 and 3 or more members. The presence of a medical school or a pediatric training program had no effect on population or births-to-APSA member ratios. There was no correlation between numbers of APSA members and state GDP or state GDP per capita. We used a low, medium, and high threshold to predict the need for pediatric surgeons based upon population per APSA member ± 1 SD (272,466 ± 163,386) to predict a need of 82 to 1344 pediatric surgeons, an increase in the APSA membership by 10% to 168%.

Conclusion

Based on population estimates and APSA membership, a current shortage of pediatric surgeons exists. Measures should be taken to address this workforce issue.     

The measurement of blood flow in mouse femur and its correlation with239Pu deposition

Summary The concentration of¹⁸F was measured in three parts of the femur and in the blood of 36 mice killed at intervals of from 1 min to 2 h after intravenous injection. Blood supply to the bone sections, calculated by dividing the increase in¹⁸F concentration in bone by the integral of¹⁸F concentration in blood between selected time intervals, was shown to be unaffected by the return of¹⁸F from bone to blood at times earlier than 90 min following injection. The supply of blood per unit mass of bone was greatest in distal end of the femur, less in proximal end and least in shaft. In whole femur average blood flow was 230 mm³ per gram fresh bone per min. The deposition of²³⁹Pu in the three parts of the mouse femur was shown to be linearly related to blood flow and the nature of the relationship is discussed.     

A comparison of chest tubes versus bulb-suction drains in pediatric thoracic surgery

Background/Purpose

Chest tubes are commonly used to evacuate the pleural space of air and fluid after thoracic surgery. The safety and efficacy of postoperative traditional chest tubes (CTs) versus soft bulb-suction drains (BDs) in the management of pediatric patients undergoing thoracic procedures were investigated.

Methods

An institutional review board-approved, retrospective review was performed on all patients who required noncardiac, nontraumatic thoracic operations from January 2000 to December 2005. Patient data included BD or CT drainage, age at operation, indication for surgery, open or thoracoscopic approach, days of postoperative drainage, the development of a postremoval pneumothorax, and complications. Statistical comparisons were made using t test and χ² test.

Results

During the study period, 186 patients with complete records underwent a thoracic operation. One hundred twenty (65%) received a CT, whereas 66 (35%) received a BD. Patients who received CT averaged 5.6 days of drainage compared with 4.4 days in the group that received BD. Postremoval pneumothorax developed in 5 (4%) patients with CT compared with 4 (6%) patients with BD. Two patients in the CT group required reinsertion of another CT. None of the BD patients required further intervention.

Conclusion

For thoracoscopic and open thoracic operations, BDs are as safe and efficacious as traditional CT.     

ASPECTS OF THE MICROCIRCULATION

The microcirculation is an important but little understood part of the cardiovascular system. As new techniques have been developed, more accurate information has become available concerning the changes in the microcirculation in both health and disease. A review has been made of some of the more important facets of the microcirculation of particular interest to surgeons. Reference is made to basic physiology, especially the mechanisms controlling flow in the microcirculation. The significance of changes in small blood vessels in hypovolæmic, septic, and progressive shock is also discussed, and the role of platelet aggregation in shock states is explored.     

Circulating mitochondrial DNA in serum: A universal diagnostic biomarker for patients with urological malignancies

ObjectiveCell-free circulating mitochondrial DNA (mtDNA) has been proposed as universal diagnostic and prognostic biomarker in cancer patients.Patients and methodsCell-free DNA was isolated from 1 ml serum from patients with bladder cancer (BCA, n = 84), renal cell carcinoma (RCC, n = 33), and prostate cancer (CaP, n = 23), and compared with healthy individuals (n = 79). Quantitative real-time PCR was used to analyze the levels of a 79 bp (mtDNA-79), and 220 bp (mtDNA-220) fragment of the mitochondrial specific 16S-RNA. The mitochondrial DNA integrity (mtDNA-integrity) was defined as ratio of mtDNA-220 to mtDNA-79 fragments.ResultsIn healthy controls, mtDNA-79 levels were increased in male volunteers; mtDNA-230 levels and mtDNA-integrity were correlated with age. Neither mtDNA levels nor mtDNA-integrity were correlated with age or gender in cancer patients. Circulating mtDNA-79 (median 8.75 × 10⁶ vs. 0.43 × 10⁶ copies/ml) and mtDNA-230 (8.11 × 10⁶ vs. 0.27 × 10⁶ copies/ml) levels were significantly increased in cancer patients and allowed sensitive (84%) and specific (97%) discrimination from healthy controls. mtDNA levels were unequally distributed among the different cancer entities (mtDNA-79: BCA 9.54 × 10⁶ vs. RCC 6.69 × 10⁶ vs. CaP 4.48 × 10⁶ copies/ml; mtDNA-230: BCA 9.78 × 10⁶ vs. RCC 6.74 × 10⁶ vs. CaP 1.94 × 10⁶ copies/ml). The mtDNA-integrity was increased in RCC and BCA patients compared to control subjects and CaP patients. Serum mtDNA-integrity was correlated with pathological stage in RCC and with tumor grade in BCA patients.ConclusionCirculating mtDNA levels are associated with gender and age in healthy individuals, but not in cancer patients. Quantification of circulating mtDNA may help identify patients with urologic malignancies.