Radiation safety education reduces the incidence of adult fingers on neonatal chest radiographs.

A previous audit revealed a high frequency of adult fingers visualised on neonatal intensive care unit (NICU) chest radiographs-representing an example of inappropriate occupational radiation exposure. Radiation safety education was provided to staff and we hypothesised that the education would reduce the frequency of adult fingers visualised on NICU chest radiographs. Two cross-sectional samples taken before and after the administration of the education were compared. We examined fingers visualised directly in the beam, fingers in the direct beam but eliminated by technologists editing the image, and fingers under the cones of the portable x-ray machine. There was a 46.2% reduction in fingers directly in the beam, 50.0% reduction in fingers directly in the beam but cropped out, and 68.4% reduction in fingers in the coned area. There was a 57.1% overall reduction in adult fingers visualised, which was statistically significant (Z value - 7.48, P < 0.0001). This study supports radiation safety education in minimising inappropriate occupational radiation exposure.

Arm placement of the Cook titanium Petite Vital-Port: results of radiologic placement in 125 patients with cancer.

OBJECTIVE: Patients with cancer require reliable venous access for therapy and phlebotomy. Traditionally, insertion of venous ports has been performed in the operating room. However, the interventional radiology service has recently become involved in the placement of a variety of venous access devices. This study examines the technique and complications associated with the placement of venous ports in the arm for patients with cancer. METHODS: Cook titanium Petite Vital-Ports (Cook Canada, Stouffville, Ont.) were implanted in patients with cancer, and implantation was performed in the medical imaging vascular/interventional suite. Patients were followed prospectively by periodic chart review for a maximum of 42 months after port insertion. Minimum follow-up in patients who did not die from cancer was 6 months. RESULTS: The authors implanted 125 Vital-Ports. The mean duration of port implantation was 265 days (range 2 to 1278 days, total catheter days 33 221). Venous thrombosis developed in 5 patients (4%, or 0.06 episodes/1000 catheter days). Four patients (3.2%, or 0.12 episodes/1000 catheter days) had suspected infection of the port or catheter, and 2 had culture-positive infection (1.6%, or 0.06 episodes/1000 catheter days). Two patients (1.6%, or 0.06 episodes/1000 catheter days) required port or catheter revision owing to mechanical difficulties. CONCLUSION: The Cook titanium Petite Vital-Port, implanted in the arm in the medical imaging vascular/interventional suite, is relatively safe and effective. As a result, it has been widely accepted by the patients and clinicians at the hospital where this study was conducted.

Doppler ultrasonographic examination of the leg veins of patients with Parkinson disease.

OBJECTIVE: To determine the incidence of deep venous thrombosis (DVT) in patients with Parkinson disease. DESIGN: Prospective study. SETTING: Outpatient neurology clinic. PATIENTS: Eighty-one patients with Parkinson disease. OUTCOME MEASURES: Duplex ultrasonographic scans consisting of M mode images and compression images, Doppler flow assessment and augmentation of flow assessment. RESULTS: Four patients had leg DVT; in 3 of the patients the thrombi were in calf veins, whereas in 1 patient the thrombosis was in the superficial femoral vein. Of the patients with DVT, 1 (1.23%) had stage 2 Parkinson disease, 1 (1.23%) had stage 2.5, and the other 2 (2.46%) had stage 4. CONCLUSIONS: There was no statistically significant difference in the incidence of DVT among patients who were more severely disabled by Parkinson disease. However, an overall incidence of DVT of 4.9% in a group of asymptomatic patients is clinically meaningful, suggesting that patients with Parkinson disease are at risk for asymptomatic leg DVT.

Interobserver variability in the measurement of internal carotid stenosis.

OBJECTIVE: To assess interobserver variability in the measurement of carotid stenoses from digital subtraction angiograms displayed in different ways (nonmagnified or magnified, white or black arteries); and to compare human readers with computer-generated densitometric measurements of vessel stenosis. METHODS: Digital subtraction angiograms of 20 proximal internal carotid artery stenoses were laser printed in the following ways: (1) Nonmagnified white artery on a black background; (2) Magnified white artery on a black background; (3) Nonmagnified black artery on a white background; (4) Magnified black artery on a white background. This resulted in 80 images of internal carotid artery stenoses. These stenoses were independently measured by 4 radiologists using the North American Symptomatic Carotid Endarterectomy Trial method. A computer-generated densitometric measurement of the black nonmagnified images was also obtained. RESULTS: The most reliable stenosis measurements were obtained from the nonmagnified black and white artery images. The interobserver variability in the measurement of internal carotid stenoses using these images was quite small. Variability increased with the use of magnification. The computer-generated stenosis measurements were consistently much higher than those of the radiologists. CONCLUSION: There was significant variability in measurements made from magnified images and between human readers and computer-generated measurements. This has great clinical significance. Readers of digital angiographic images must determine the most reliable, reproducible images generated by their equipment, as these measurements significantly affect treatment of patients with symptomatic internal carotid artery stenosis.

Traumatic pseudoaneurysm of the hepatic artery after percutaneous liver biopsy and laparoscopic cholecystectomy in a patient with biliary cirrhosis: a case report.

Hemobilia is a rare but recognizable complication of percutaneous transhepatic diagnostic or therapeutic procedures. The diagnosis is sometimes difficult because of the time lag between the procedure and the first symptoms, which can be intermittent. A 35-year-old woman had hemobilia after percutaneous Trucut biopsy of the liver followed by laparoscopic cholecystectomy. The diagnosis of hemobilia was made on clinical grounds, and a pseudoaneurysm of the right hepatic artery was detected on selective angiography. The patient was successfully treated with arterial embolization during angiography.

Comparison of digital angiographic images with conventional radiographs for detection of pneumothorax after needle biopsy of lung.

OBJECTIVE: To compare the rate of detection of pneumothoraces from images obtained from a digital angiographic system (1024 x 1024 matrix) and from conventional film-screen chest radiographs, following fine-needle biopsy of the lung. PATIENTS AND METHOD: For 102 patients who underwent fine-needle biopsy, 2 digital fluoroscopic chest images and 1 film-screen chest radiograph were obtained during expiration after the biopsy. The images were interpreted by 4 blinded readers. RESULTS: There were 30 pneumothoraces, of which 96.6% were detected from standard chest radiographs and 54.2% were detected from digital images. CONCLUSIONS: The detection of pneumothorax from digital images was far inferior to that from standard film-screen chest radiographs. Therefore, standard chest radiographs are recommended after fine-needle biopsy of the lung.

Pseudoaneurysm secondary to pancreatitis presenting as GI bleeding.

Pseudoaneurysm formation is a rare but potentially dev approximately astating complication of pancreatitis. It can be diag approximately nosed by using various imaging modalities including computer tomography, ultrasound, and angiography and should be entertained in any patient with a history of pancreatitis. We present the imaging findings in three patients with pseudoaneurysm formation secondary to pancreatitis who initially presented with gastrointestinal bleeding.

Respiratory outcomes with early extubation after coronary artery bypass surgery.

OBJECTIVE: Aortocoronary bypass surgery has undergone recent changes, promoting the concept of "fast tracking," in which patients are extubated and discharged postoperatively at an accelerated pace compared with previous historic patterns. Postoperative respiratory function and complications have not been previously studied in patients selected for "fast tracking." DESIGN: Matched retrospective cohort study. SETTING: Referral university teaching hospital. PATIENTS: Thirty-one patients who were compared with a retrospective matched cohort of 112 patients. Matching was based on forced vital capacity, age, and gender. INTERVENTIONS: Respiratory physiological outcomes defined as pneumonia, postoperative pulmonary spirometry, chest x-ray atelectasis or lobar collapse, and gas exchange were compared. MAIN RESULTS: The increase in atelectasis score compared with preoperative (0 = no atelectasis, 4 = lobar collapse) was higher (p < 0.01) on the day of extubation in the late extubation group (4.1 +/- 1.4) compared with the early extubation group (2.6 +/- 1.3). These chest radiographic findings were not related to pain (0 to 10 visual analog scalei, which were equivalent between groups (4.0 +/- 2.3 v 4.2 +/- 1.6). The decreases in spirometry on postoperative day 5 (FVC 1.15 +/- 0.42 v 0.86 +/- 0.54 liters; FEV1 0.92 +/- 0.38 v 0.59 +/- 0.50 liters) were greater (p < 0.001) in the late extubation group. A significantly (p < 0.001) greater decrease in FEV1/FVC ratio in the late extubation group (3.25 +/- 0.87 v -1.6 +/- 1.11%) was indicative of greater airway obstruction. Fluid balance until extubation was greater in the late extubation group (4.0 +/- 2.1 v 1.4 +/- 1.2 liters). CONCLUSIONS: Differences in chest radiographs in the late extubation group at the time of extubation may be related to greater use of fluids or increased airway obstruction. The rationale of early extubation is based on cost minimization to decrease hospital duration. This article suggests that respiratory physiological outcomes are not worsened in patients who are extubated and discharged early after elective aortocoronary bypass surgery.

Retroperitoneal actinomycosis masquerading as inflammatory pseudotumor.

Inflammatory pseudotumors present clinically as mass lesions and microscopically show a spectrum of nonspecific inflammatory and regenerative changes. When the mesentery or retroperitoneum are involved, differentiation from inflammatory fibrosarcoma poses a diagnostic problem. The authors report on a 7-year-old boy who presented with fever, anemia, weight loss, and a retroperitoneal mass. Needle biopsy results of the mass showed features consistent with inflammatory pseudotumor. Examination of the resected mass showed actinomycosis.

Depletion of activated neutrophils by a filter during cardiac valve surgery.

PURPOSE: To determine whether inclusion of a neutrophil-specific filter into the extracorporeal circuit during open heart valve surgery alters postoperative outcomes. METHODS: Convenience sampling of 24 patients undergoing elective open heart valve surgery between July 1993 and June 1994. Patients were randomized to a neutrophil-specific filter (n = 11) or to a standard blood filter (n = 13) during cardiopulmonary bypass. RESULTS: Neutrophil-specific filter diminished (P < 0.02) the expression of CD18, a neutrophil surface adhesion molecule, at I (84.5 +/- 4.2 vs 94.8 +/- 3.8%), 4 (80.0 +/- 4.2 vs 95.1 +/- 3.9%) and 24 hr (75.2 +/- 4.2 vs 98.2 +/- 3.9%) post-operatively compared with standard filter. Total white blood cell count, neutrophil count, and pro-inflammatory cytokines (IL-6, IL-8) were similar between groups at all times. Measured outcomes including: PaO2 cardiac index, ejection fraction, haemodynamic variables, use of inotropes, spirometry (FEV1, FVC), and hospitalization duration were similar between groups. CONCLUSIONS: Inclusion of the neutrophil filter during open heart valve surgery selectively depletes activated neutrophils. There were no other detectable differences between the two groups and the use of a neutrophil-specific filter in routine clinical practice for patients undergoing open heart valve surgery is not supported.

Respiratory function after cardiac surgery.

STUDY OBJECTIVE: Cardiac surgery is complicated by decreased postoperative respiratory muscle strength and spirometry with accompanying increased atelectasis. The specific respiratory symptoms attributable to these physiologic changes are unknown, and this study looked at the symptoms and underlying physiology. DESIGN: Convenience sampling of observational cohort. SETTING: Tertiary care university hospital. PATIENTS: One hundred thirty-eight patients undergoing elective surgery were enrolled. INTERVENTIONS: Changes from admission to 8-week postoperative values in atelectasis, pleural effusions, spirometry (forced vital capacity and forced expiratory volume in one second), and respiratory muscle strength (negative inspiratory pressure) were measured. These physiologic changes were compared with changes in respiratory symptoms of cough, wheeze, phlegm, and dyspnea on walking up a slight hill noted from admission to 8-week follow-up by stepward logistic regression. MEASUREMENTS AND RESULTS: Spirometry and negative inspiratory pressure decreased and atelectasis increased from admission to discharge. These disturbances had only incompletely resolved at 8-week follow-up. Some patients reported fewer symptoms of cough (11%), phlegm (9%), wheeze (35%), and dyspnea (46%) at 8 weeks follow-up. Other patients reported increased symptoms of cough (15%), phlegm (10%), wheeze (6%), and dyspnea (4%) at 8 weeks follow-up. Residual atelectasis at 8 weeks was predictive of fewer symptoms of dyspnea (odds ratio [OR] 0.335, p = 0.199; 95% confidence interval [CI] 0.188, 0.597), increased symptoms of dyspnea (OR 855, p = 0.006; 95% CI 6.6, 11052), and increased symptoms of cough (OR 260, p = 0.023; 95% CI 2.13, 31829). Negative inspiratory pressure at 8 weeks was predictive of fewer symptoms of dyspnea (OR 1.05, p = 0.032; 95% CI 1.02, 1.09) and increased symptoms of wheeze (OR 0.7, p = 0.45; 95% CI 0.533, 0999). Forced vital capacity at 8 weeks was predictive of increased symptoms of wheeze (OR 0.005; p = 0.015; 95% CI 0.0060, 0.775). CONCLUSIONS: Postoperative changes in respiratory muscle strength and spirometry can persist up to at least 8 weeks postoperatively. Many patients report a change in respiratory symptoms of cough, phlegm, dyspnea, or wheeze. The change in respiratory symptoms at 8 weeks is correlated with residual respiratory muscle weakness, decrease in spirometry, and residual atelectasis.

The effect of physical therapy on respiratory complications following cardiac valve surgery.

STUDY OBJECTIVE: To determine whether higher personnel intensive chest physical therapy can prevent the atelectasis that routinely follows cardiac valve surgery. DESIGN: Randomized, controlled trial. SETTING: Tertiary care hospital. PATIENTS: Seventy-eight patients undergoing elective cardiac valve surgery between October 1991 and April 1993 were enrolled. INTERVENTIONS: Patients were randomized in an unmasked fashion to receive early mobilization and sustained maximal inflations (lower-intensity treatment) or to receive early mobilization, sustained maximal inflations, and single-handed percussions (higher-intensity treatment.) MEASUREMENTS AND RESULTS: Clinical efficacy was determined by extent of atelectasis, length of ICU stay, total length of hospital stay, and personnel costs. The extent of postoperative atelectasis was similar in both groups on the fifth postoperative day. Postoperative values of FVC and FEV1 were reduced to a similar extent in both groups. Hospital stays and ICU stays were similar regardless of treatment. Physical therapy costs were highest in the higher-intensity therapy group. CONCLUSIONS: Postoperative respiratory dysfunction is common but does not usually cause significant morbidity or prolong hospital stay. The routine prescription of high-intensity physical therapy does not improve patient outcomes but does add significantly to patient costs.

Nephrotoxicity of ioxaglate and ioversol assessed by glomerular filtration rate: a pilot study.

OBJECTIVE: To determine the effect of ioxaglate and ioversol on glomerular filtration rate (GFR) in a heterogeneous inpatient group to allow calculation of the necessary sample size for a randomized trial. PATIENTS AND METHODS: The study group consisted of 36 men and 12 women, ranging in age from 25 to 79 (mean 63) years. Fourteen of the patients, those undergoing abdominal aortography with or without renal arteriography, received ioxaglate (Hexabrix 320; 40 to 240 [mean 141] mL), and the remaining 34, those receiving intravenous injections and those undergoing computed tomography with arterioportography or carotid arteriography, received ioversol (Optiray 320; 20 to 180 [mean 87] mL). GFR was measured by determining the clearance of diethyl-enetriaminepenta-acetic acid labelled with technetium-99m up to 72 hours before and 24 hours after administration of the contrast medium. Risk factors for nephrotoxicity included diabetes (7 patients) and pre-existing renal impairment (mild in 11 and severe in 6). RESULTS: GFR decreased by 20% to 34% in six patients (13%); in only one of these was the serum level of creatinine increased at 24 hours. One of these six patients had received 120 mL of ioversol for carotid arteriography and had no risk factors for nephrotoxicity. The other five had received 40 to 187 (mean 115) mL of ioxaglate, three for abdominal aortography and two for selective renal arteriography. The risk factors in these patients included diabetes (two patients) and severe pre-existing renal impairment (two patients). Renal failure necessitating treatment did not develop in any of the patients. CONCLUSIONS: A decrease in GFR occurred more often with ioxaglate than with ioversol and usually occurred in patients with additional risk factors. Injection of contrast medium into the abdominal aorta or the renal artery may increase the risk of nephrotoxicity. Changes in serum level of creatinine at 24 hours were not reliable in identifying patients with decreased GFR. On the basis of these data, the authors estimate that a group of 194 patients would be necessary for a randomized trial comparing the nephrotoxicity of ioxaglate and ioversol for abdominal aortography.

Temporary inferior vena cava filters: in vitro comparison with permanent IVC filters.

PURPOSE: An in vitro comparison of clot-trapping abilities of permanent and temporary inferior vena cava (IVC) filters. MATERIALS AND METHODS: A flow model was used to simulate the IVC. Two permanent IVC filters, the titanium Greenfield and LG-Medical (LGM), were compared with two temporary filters, the Filcard International and Gunther. Clot sizes used were 2.5 x 2.5 mm, 2.5 x 5 mm, 5 x 5 mm, 5 x 10 mm, and 5 x 20 mm. Individual clots were presented to the filters with the simulated IVC in a horizontal or vertical orientation. Clot-trapping dynamics and pressure gradient changes during the injection of multiple, sequential clots were also examined. RESULTS: As clot size diminished, all filters trapped fewer clots; however, the temporary filters trapped more small clots than the permanent filters. Very little difference was observed in clot-trapping abilities among the filters for clots of 5 x 10 mm or greater. In the horizontal orientation, the permanent filters trapped 38% of all clots delivered, while the temporary filters trapped 73%, chi 2 = 24.8 (P < .001). In the vertical orientation, the overall clot-trapping abilities of the filters improved, with the permanent filters trapping 73% of all clots delivered, while the temporary filters trapped 95%, chi 2 = 18 (P < .001). During trapping of multiple clots, the temporary filters allowed fewer clots to pass. CONCLUSION: The temporary filters performed better than the permanent filters in both individual clot-trapping orientations. During multiple clot-trapping experiments, fewer clots were allowed to pass by the temporary filters. The temporary filters demonstrated the ability to capture clots both inside and outside the wire struts.

Depletion of neutrophils by filter during aortocoronary bypass surgery transiently improves postoperative cardiorespiratory status.

STUDY OBJECTIVE: To determine whether inclusion of a leukocyte specific filter into the extracorporeal circuit during aortocoronary bypass surgery alters postoperative cardiopulmonary function. DESIGN: Randomized, double-blinded control trial. SETTING: Tertiary care hospital. PATIENTS: Convenience sampling of patients undergoing elective aortocoronary bypass between October 1992 and June 1993. INTERVENTIONS: A total of 32 patients were randomized to a leukocyte specific filter (n = 16) or to a standard blood filter (n = 16) during the surgical procedure. MEASUREMENTS AND RESULTS: White blood cell count in the standard filter group (12.2 +/- 3.6 10(9)/L) was higher (p = 0.047) than in the leukocyte filter group (9.9 +/- 2.6 10(9)/L) at 4 h postoperatively but counts were similar (p = 0.063) at 24 h (10.8 +/- 2.7 vs 8.9 +/- 2.6 10(9)/L, respectively). Leukocyte activation assessed by chemiluminescence was similar between groups at all measurement periods. We noted transient improvements (p < 0.05) in intrapulmonary shunt (19 +/- 50% vs 24 +/- 9%) and mean blood pressure (85 +/- 8 vs 76 +/- 9 mm Hg, respectively) in the leukocyte filter group compared with the standard filter group, respectively. Otherwise there were no differences noted between groups. CONCLUSIONS: Inclusion of a leukocyte filter during cardiopulmonary bypass caused transient cardiorespiratory improvement that was lost within 24 h and did not offer any significant clinical benefits.

Transcranial Doppler signals during cerebral angiography and cardiac catheterization.

Cerebral angiography is associated with a 0.45-4% risk of neurological complications and a less than 1% risk of permanent neurological deficit. Recently, air embolism has been implicated as a major cause of these complications. Cardiac catheterization is associated with a neurological complication rate of less than 1%; the predominant mechanism appears to be embolic. We used transcranial Doppler ultrasonography to detect high-intensity signals suspected to be related to air emboli, a potential cause of neurological complications in patients undergoing coronary and carotid angiography. We prospectively examined a total of 42 consecutive patients with transcranial Doppler ultrasound. Twenty-one patients underwent cerebral angiography, and 21 patients underwent cardiac catheterization. In both groups of patients, high-intensity bidirectional Doppler signals were recorded during different phases of angiography. High-intensity, longduration Doppler signals completely masking the background cardiac cycle signals were observed during machine-powered rapid injection of contrast medium with good correlation between the duration of Doppler signals and the duration of automated injection. In addition, high-intensity signals of much shorter duration were also observed during manual injection of saline or contrast medium and during catheter manipulation. In our study, the high-intensity Doppler signals recorded were identical in all patients who underwent cerebral and coronary angiography. No spontaneous emboli were seen. None of our 42 patients developed any type of neurological symptoms during or after the procedure. These high-intensity signatures do not represent air embolism exclusively; rather, they are likely a combination of turbulence in the bloodstream created during rapid injection, air emboli, and, perhaps, echogenicity of the contrast medium.

Preliminary clinical experience with the Gunther temporary inferior vena cava filter.

PURPOSE: The authors describe their preliminary clinical experience with the Gunther temporary inferior vena cava (IVC) filter. PATIENTS AND METHODS: Seven women and 10 men, mean age 52 years (range, 19-85 years), were treated with the temporary IVC filter. Indications for filter placement were pulmonary embolism (PE) in four patients and iliofemoral deep venous thrombosis in six. In these patients anticoagulation was contraindicated because of planned major surgery. Filters were placed in four patients following massive PE and in three for prophylaxis following cranial trauma. Four patients had underlying malignant disease. Filters were introduced through the right common femoral vein in 14 patients, the left common femoral vein in two, and the left internal jugular vein in one. RESULTS: No patient developed recurrent PE with the filter in place. All filters were removed without complication 3-14 days (mean, 7 days) after placement. Two of the patients with underlying malignant disease required placement of a permanent filter. Two patients developed IVC thrombosis with the filter in place, and both developed recurrent PE after filter removal. Two patients developed insertion vein thrombosis. One patient developed a bleeding disorder that caused a massive hematoma at the insertion vein site, which may have contributed to her death. CONCLUSION: The Gunther temporary filter can be used in selected patients; however, patients with underlying malignant disease may be more appropriately treated with a permanent filter. The temporary filter does not appear to reduce the rate of insertion vein and IVC thrombosis.