The dimensions of the posterior arch of C2 for instrumented screw fixation. A radiological study in the Spanish population

BACKGROUND

To describe the feasibility of the posterior arch of C2 accepting two crossing screws in the Spanish population.

METHODS

One hundred and fifty patients who underwent a routine neck CT scan for non-cervical pathology were enrolled. Submillimeter slices (thickness 0.7 mm) every 0.4 mm were performed with a 64 multi-detector CT scan, which allows isometric measurements. We measured the length and height of the cortical and cancellous (endomedullar) region of the lamina and the spinous process, inclination, maximal screw length and spinolaminar angle.

RESULTS

The average (standard deviation) measurements of the lamina were: width of the left cortical 7.2 (1.5) mm, right cortical 6.9 (1.3) mm, width of the cancellous part of the left lamina 4.8 (1.5) mm, right side 4.6 (1.4) mm. The mean left cortical height was 13.0 (1.5) mm and 13.1 (1.6) mm for the right. The mean height of the cancellous part was 9.0 mm for both sides. The average measurements of the spinous process were: cortical length 15.7 (3.5) mm, endomedullar length 12.5 (3.9) mm; cortical height 11.9 (2.2) mm, endomedullar height 8.4 (2.1) mm; spinolaminar angle 49º (4); the maximum screw length 3.18 cm, and the inclination angle 143º.

CONCLUSION

A CT scan with submillimeter slices is necessary in order to avoid malpositioning of the screws. The outer cortical measurements are 2 to 4 mm bigger than the endomedullar ones. Taking into account the dimensions of the spinous process, 24% of the population would not be candidates for this crossing screw technique.

Postoperative nausea and vomiting: physiopathology, risk factors, prophylaxis and treatment

Recognising the importance of the prevention and early treatment of postoperative nausea and vomiting (PONV) is essential to avoid postoperative complications, improve patient satisfaction and enable the development of major outpatient surgery and fast-track surgery. The topic of PONV might seem to have become stagnant, but we are moving forward. New concepts and problems like post-discharge nausea and vomiting, new risk factors and new drugs are appearing. However, there continue to be mistaken notions about PONV, such as the association between PONV and post-anaesthesia care unit stays, or assuming that it is a risk factore characteristic of the patient, anaesthesia or surgery when it is not. Perhaps, now is the moment to tackle PONV in a different manner, implementing guidelines and going for more aggressive prophylaxis in some groups of patients. We present an extensive review of this topic.

Dual source CT: state of the art in the depiction of coronary arteries anatomy, anatomical variants and myocardial segments

Cardiovascular disease is the leading cause of death in adults in western countries. Coronary angiography remains the gold standard for the diagnosis of coronary artery disease, a procedure that carries risks. Nowadays, a significant number of the coronary angiographies performed every year are only diagnostic. Multidetector computed tomography (MDCT) allows non-invasive evaluation of coronary arteries. It is a continuously developing technique, and actually the top technology is represented by Dual Source CT. This scanner of new conception permits an improvement in image quality, and visualization of distal vessels and small collateral branches. The aim of our work is to illustrate the actual state of the art in non-invasive coronary arteries evaluation represented by Dual Source CT, presenting images of coronary arteries normal anatomy, anatomical variants and myocardial segment.

[Postoperative nausea and vomiting and opioid-induced nausea and vomiting: guidelines for prevention and treatment]

Postoperative nausea and vomiting (PONV) causes patient discomfort, lowers patient satisfaction, and increases care requirements. Opioid-induced nausea and vomiting (OINV) may also occur if opioids are used to treat postoperative pain. These guidelines aim to provide recommendations for the prevention and treatment of both problems. A working group was established in accordance with the charter of the Sociedad Española de Anestesiología y Reanimación. The group undertook the critical appraisal of articles relevant to the management of PONV and OINV in adults and children early and late in the perioperative period. Discussions led to recommendations, summarized as follows: 1) Risk for PONV should be assessed in all patients undergoing surgery; 2 easy-to-use scales are useful for risk assessment: the Apfel scale for adults and the Eberhart scale for children. 2) Measures to reduce baseline risk should be used for adults at moderate or high risk and all children. 3) Pharmacologic prophylaxis with 1 drug is useful for patients at low risk (Apfel or Eberhart 1) who are to receive general anesthesia; patients with higher levels of risk should receive prophylaxis with 2 or more drugs and baseline risk should be reduced (multimodal approach). 4) Dexamethasone, droperidol, and ondansetron (or other setrons) have similar levels of efficacy; drug choice should be made based on individual patient factors. 5) The drug prescribed for treating PONV should preferably be different from the one used for prophylaxis; ondansetron is the most effective drug for treating PONV. 6) Risk for PONV should be assessed before discharge after outpatient surgery or on the ward for hospitalized patients; there is no evidence that late preventive strategies are effective. 7) The drug of choice for preventing OINV is droperidol.

[Quantification of left ventricular function and mass in dual-source CT (DSCT).]

OBJECTIVES

To evaluate the interobserver agreement in quantifying left ventricular function and mass and to assess the accuracy of conventional manual contour tracing compared to semiautomatic segmentation analysis software.

MATERIAL AND METHODS

Twenty consecutive subjects who underwent cardiac DSCT with retrospective ECG-gating were included. Two different multiphase image reconstructions were done in 5% steps throughout the entire cardiac cycle (0-95% of the R-R interval) with effective slice thickness of 1mm in the axial plane and 8mm in the short-axis orientation. Left ventricular function and mass were calculated by two independent observers, tracing endocardial and epicardial borders manually and using a semiautomatic software tool (Circulation II, Siemens). Ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), cardiac output (CO), and myocardial mass were evaluated by two independent observers blind to each other's assessments. The interobserver agreement and the reliability of the different segmentation methods were calculated. The time required for manual contouring and semiautomatic contour tracing was also registered.

RESULTS

We found an excellent correlation (r>0.94; p<0.05) between the two independent observers for the quantification of left ventricular function and mass. Left ventricular functional parameters derived from semiautomatic contour software and conventional manual tracing method were not significantly different (p>0.05). The semiautomatic contour detection algorithm overestimated LV mass significantly compared with the manual contouring method (mean difference 29.45+/-1.64g; p<0.05). The time needed to calculate these parameters with the semiautomatic tool was significantly lower (248.85+/-99.8s) than with manual contouring (452.7+/-73.92s) (p<0.05).

CONCLUSIONS

Interobserver agreement for quantifying left ventricular function and mass using DSCT is excellent. Despite overestimating left ventricular mass, the semiautomatic software tool allows cardíac parameters to be quantified with the same reliability as the conventional manual method in half the time.

Global cardiac evaluation without heart rate control: preliminary experience with dual source CT (DSCT)

AIM

The aim of this work was to assess the role of dual source computed tomography (DSCT) in global cardiac evaluation without heart rate control, assessing the effect of average heart rate on coronary image quality, optimal reconstruction interval, ventricular function, and evaluation of left chamber valves.

METHODS

Fifteen consecutive patients under-went coronary CT angiography. For coronary evaluation, data sets were reconstructed in 5% steps from 30% to 80% of the RR interval. For the assessment of cardiac function, image were reconstructed with a slice thickness of 2.0 mm and 2.0 mm increment, at 10% steps from 0% to 90% of the RR interval. Two blinded independent readers assessed the image quality of the coronary arteries and left chamber valves.

RESULTS

The mean heart rate during the scan was 73+/-11.8 bpm (range 56-97). At the best reconstruction interval excellent diagnostic image quality (score 4) was achieved in 95.5% (43/45) of coronary arteries. Excellent inter-observer agreement was observed for image quality rating (k=0.82). No significant correlation was found between the average heart rate and the mean quality scores (rho=0.29). Comparison of image quality of the coronary arteries in systolic and diastolic reconstructions in each patient showed no statistically significant differences.

CONCLUSION

DSCT is an excellent technique for global cardiac imaging, as it allows to obtain coronary arteries of excellent quality and evaluate ventricular function and valvular area independent of the heart rate.

[Dual-source CT coronary angiography]

Multidetector computed tomography (MDCT) has been demonstrated to be a very useful technique to non-invasively study coronary arteries. Despite the high spatial and temporal resolution of 64-slice MDCT scanners, this technique has several limitations. Dual-source computed tomography (DSCT) allows to study coronary arteries with excellent diagnostic quality in all subjects independent of the heart rate, thus avoiding the use of beta-blockers. In this article DSCT studies from three subjects with elevated heart rate and irregular heart rhythm are described. Usefulness of this technique to obtain studies of excellent quality in cases in which conventional 64-row-MDCT might present limitations is emphasized.

Single-dose aprepitant vs ondansetron for the prevention of postoperative nausea and vomiting: a randomized, double-blind phase III trial in patients undergoing open abdominal surgery

BACKGROUND

The neurokinin(1) antagonist aprepitant is effective for prevention of chemotherapy-induced nausea and vomiting. We compared aprepitant with ondansetron for prevention of postoperative nausea and vomiting.

METHODS

Nine hundred and twenty-two patients receiving general anaesthesia for major abdominal surgery were assigned to receive a single preoperative dose of oral aprepitant 40 mg, oral aprepitant 125 mg, or i.v. ondansetron 4 mg in a randomized, double-blind trial. Vomiting episodes, use of rescue therapy, and nausea severity (verbal rating scale) were documented for 48 h after surgery. Primary efficacy endpoints were complete response (no vomiting and no use of rescue therapy) 0-24 h after surgery and no vomiting 0-24 h after surgery. The secondary endpoint was no vomiting 0-48 h after surgery.

RESULTS

Aprepitant at both doses was non-inferior to ondansetron for complete response 0-24 h after surgery (64% for aprepitant 40 mg, 63% for aprepitant 125 mg, and 55% for ondansetron, lower bound of 1-sided 95% CI > 0.65), superior to ondansetron for no vomiting 0-24 h after surgery (84% for aprepitant 40 mg, 86% for aprepitant 125 mg, and 71% for ondansetron; P < 0.001), and superior for no vomiting 0-48 h after surgery (82% for aprepitant, 40 mg, 85% for aprepitant, 125 mg, and 66% for ondansetron; P < 0.001). The distribution of peak nausea scores was lower in both aprepitant groups vs ondansetron (P < 0.05).

CONCLUSIONS

Aprepitant was non-inferior to ondansetron in achieving complete response for 24 h after surgery. Aprepitant was significantly more effective than ondansetron for preventing vomiting at 24 and 48 h after surgery, and in reducing nausea severity in the first 48 h after surgery. Aprepitant was generally well tolerated.

[Intestinal pneumatosis and portomesenteric gas: a case review]

Intestinal pneumatosis (presence of gas in the intestinal wall and in the portomeseteric veins) is an infrequent clinical situation that has been associated with extended bowel necrosis and fatal outcome. However, there are other reasons that can justify these findings without such an outcome. Recent advances in diagnostic imaging techniques, especially multislice computerized tomography (MSCT), have allowed precise and quick diagnosis of these entities. In this article, we review the MSCT radiological manifestations of intestinal pneumatosis, as well as the different diagnoses related with the findings observed in a patient diagnosed with esophageal carcinoma under chemotherapy treatment.

[Vascular access guidelines for hemodialysis]

Quality of vascular access (VA) has a remarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Spanish Society of Neprhology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care, monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to make aproppiate decissions. Several quality standars are also included.

[Video-assisted thoracoscopy for resecting solitary pulmonary nodules]

The objective of this study was to evaluate the usefulness of video assisted thoracoscopy in the resection of solitary pulmonary nodules. Thirty-three patients with solitary pulmonary nodules diagnosed by video assisted thoracoscopy were enrolled prospectively. A preoperative computed tomography scan was obtained for each patient. Harpoons were implanted preoperatively to locate the lesion in patients whose tumors were in the parenchyma. When endoscopic resection proved impossible in five patients, the surgeon resorted to thoracotomy. All were diagnosed after the procedure. One was a case of pulmonary lymphoma, 2 were primary adenocarcinomas of the lung, 2 were oat-cell cancers, 1 was Wegener's disease, 4 were tuberculomas, 3 involved pulmonary infarction and 20 were single pulmonary metastases. Patients who needed thoracotomy required more days of postsurgical drainage (p < 0.05). The size of resected nodules ranged from 0.4 to 6 centimeters. Preoperative positron emission tomographs were available for four patients. No perioperative (< 30 days) mortality occurred and morbidity consisted of one case of prolonged airway leak (> 7 days). Use of video-assisted thoracoscopy reduced perioperative morbidity and hospital stay.

[Reconstruction of a palatal defect with pedicled myomucosal flap of buccinator muscle]

The myomucosal flap from buccinator muscle is a versatile flap useful on reconstruction of defects located in the palatine region. We report the case of a vascular tumor located in the left palate which was removed and rebuilt with a myomucosal flap taken from buccinator muscle. We proceed previously to the embolization of its nutritional artery (a. palatina major).

Combined percutaneous-endoscopic pancreatic pseudocyst drainage--a new technique

Surgical drainage has been the traditional approach to treating pancreatic pseudocysts. Percutaneous and endoscopic treatment of pancreatic pseudocyst were recently suggested as an alternative to surgery. In order to avoid the difficulties that can be observed in some patients in the percutaneous or endoscopic management of pancreatic pseudocysts we have used a combined procedure. We have treated by the "rendezvous" technique two patients suffering from pancreatic fistula complicating pancreatic pseudocysts. A percutaneous-endoscopic approach was used to place an internal stent between the pseudocyst and the duodenum. We have applied the same combined approach to the main pancreatic duct that is usual for bile duct obstruction without noticeable complications. Although application of this technique will be very limited, we advocate in the future the combined approach to treating pancreatic pseudocyst when there is a fistula between the fluid collection and pancreatic duct, and the downstream main pancreatic duct is obstructed, preventing use of the transpapillary approach.

[Endoscopic resection of juvenile nasopharyngeal fibromas]

Current surgical approaches to juvenile nasopharyngeal angiofibromas (JNA) are exclusively external. This implies not only incisions that are mostly visible, but also a potential loss of function as well as secondary lesions and high perioperative risks. Radiotherapy aims to avoid surgery, but cannot exclude complications and possible sequelae. These consequences are commonly accepted as the "costs" for both therapies, although neither is negligible. For both surgery and radiotherapy, recurrences or persistence rates have been described, so that outcome may result in questions for the treatment used as well as the complications or sequelae. We report our experiences with two cases of JNA operated on under endoscopic control and discuss our indications for the endoscopic approach to these tumors, preoperative conditions, surgical technique, and the possible difficulties of surgery and outcome. Our results encourage us to recommend use of endoscopic surgery as a valid alternative method to approach resections of certain JNA.

Jugular venous oxygen monitoring: a helpful technique in the early diagnosis of a traumatic carotid-cavernous sinus fistula

This report describes the early diagnosis of a right traumatic carotid-cavernous sinus fistula (CCSF) in a patient with head injury manifested as an acute increase in right jugular venous oxygen saturation and with no ophthalmic clinical signs. High values of jugular venous oxygen saturation must be cautiously interpreted with the clinical examination and computed tomographic findings to establish an accurate diagnosis of hyperemia with or without a CCSF.

Percutaneous vascular and nonvascular puncture under US guidance: role of color Doppler imaging

Although ultrasound guidance is extensively used in percutaneous interventional procedures, the limitations of B-mode, gray-scale sonographic guidance can restrict clinical use. Little attention has been paid to the use of color Doppler sonography during such procedures. There are several ways in which color Doppler sonography can facilitate percutaneous procedures that involve insertion of a needle or catheter. The advantages of color Doppler sonography include the following: (a) better visualization of the shaft and tip of the needle, especially in solid, echogenic lesions, when the needle is moving, or when the beam-needle angle is narrow; (b) improved targeting of either vessels or non-vascular structures (ie, biliary ducts) to be punctured; (c) avoidance of interposed vascular structures and highly vascular areas during puncture of lesions; (d) improved visualization of poorly echogenic catheters, allowing proper placement; and (e) prompt detection of complications, including active bleeding, after withdrawal of the needle.

CT-guided paracoccygeal drainage of pelvic abscesses

OBJECTIVE

Using the transrectal/transvaginal routes for the drainage of pelvic abscesses complicating colorectal surgery (anterior resection or abdominoperineal resection) is not always possible. The conventional transgluteal approach through the greater sciatic foramen, although proven to be a valuable access route, can have complications (mainly local pain).

MATERIALS AND METHODS

To avoid these difficulties, a CT-guided paracoccygeal-infragluteal approach was used in the percutaneous drainage of deep pelvic (presacral and ischiorectal) abscesses presenting after colorectal surgery in six patients.

RESULTS

Percutaneous drainage through this approach was successful in preventing the need for surgery in all six patients. No complications or recurrences were noted, and catheters were removed an average of 15 days after insertion.

CONCLUSION

In comparison with the classical transgluteal approach, the paracoccygeal-infragluteal approach minimizes patient discomfort and minimizes the risk of potential injury to the sciatic plexus or blood vessels. This initial series shows that a CT-guided paracoccygeal-infragluteal approach is well tolerated, safe, and effective for the percutaneous drainage of pelvic abscesses developing after colorectal surgery.