Action guidance for addressing pollution from inhalational anaesthetics.

Climate change is a real and accelerating existential danger. Urgent action is required to halt its progression, and everyone can contribute. Pollution mitigation represents an important opportunity for much needed leadership from the health community, addressing a threat that will directly and seriously impact the health and well-being of current and future generations. Inhalational anaesthetics are a significant contributor to healthcare-related greenhouse gas emissions and minimising their climate impact represents a meaningful and achievable intervention. A challenge exists in translating well-established knowledge about inhalational anaesthetic pollution into practical action. CODA is a medical education and health promotion charity that aims to deliver climate action-oriented recommendations, supported by useful resources and success stories. The CODA-hosted platform is designed to maximise engagement of the global healthcare community and draws upon diverse experiences to develop global solutions and accelerate action. The action guidance for addressing pollution from inhalational anaesthetics is the subject of this article. These are practical, evidence-based actions that can be undertaken to reduce the impact of pollution from inhalational anaesthetics, without compromising patient care and include: removal of desflurane from drug formularies; decommissioning central nitrous oxide piping; avoidance of nitrous oxide use; minimising fresh gas flows during anaesthesia; and prioritising total intravenous anaesthesia and regional anaesthesia when clinically safe to do so. Guidance on how to educate, implement, measure and review progress on these mitigation actions is provided, along with means to share successes and contribute to the essential, global transition towards environmentally sustainable anaesthesia.

Analysis of the acute postoperative pain experience following oral surgery: identification of 'unaffected', 'disabled' and 'depressed, anxious and disabled' patient clusters.

BACKGROUND: Pain is defined as both a sensory and an emotional experience. Acute postoperative tooth extraction pain is assessed and treated as a physiological (sensory) pain while chronic pain is a biopsychosocial problem. The purpose of this study was to assess whether psychological and social changes occur in the acute pain state. METHODS: A biopsychosocial pain questionnaire was completed by 438 subjects (165 males, 273 females) with acute postoperative pain at 24 hours following the surgical extraction of teeth and compared with 273 subjects (78 males, 195 females) with chronic orofacial pain. Statistical methods used a k-means cluster analysis. RESULTS: Three clusters were identified in the acute pain group: 'unaffected', 'disabled' and 'depressed, anxious and disabled'. Psychosocial effects showed 24.8 per cent feeling 'distress/suffering' and 15.1 per cent 'sad and depressed'. Females reported higher pain intensity and more distress, depression and inadequate medication for pain relief (p < 0.001). Distress and depression were associated with higher pain intensity. The developed questionnaire had tested reliability (test-retest r = 0.89) and estimated validity. CONCLUSION: Cluster analysis showed constituent groups with a range of psychosocial effects in acute postoperative dental extraction pain and is associated with an increase in pain intensity.

Shortened analog of the gramicidin A channel argues for the doubly occupied channel as the dominant conducting state.

A shortened analog of the gramicidin A transmembrane channel has been synthesized and its transport characterized in planar lipid bilayer membranes. General considerations of a shorter diffusional length and a shorter distance over which the voltage drop occurs (i.e., an increased electric field) would contribute to an increase in single-channel conductance. The finding of a decreased single-channel conductance supports the perspective that the dominant conducting state is the doubly occupied channel wherein distance-dependent repulsion due to the first ion in the channel impedes entry of the second ion in the shorter channel.

Prostate seed implant quality assessment using MR and CT image fusion.

PURPOSE: After a seed implant of the prostate, computerized tomography (CT) is ideal for determining seed distribution but soft tissue anatomy is frequently not well visualized. Magnetic resonance (MR) images soft tissue anatomy well but seed visualization is problematic. We describe a method of fusing CT and MR images to exploit the advantages of both of these modalities when assessing the quality of a prostate seed implant. METHODS AND MATERIALS: Eleven consecutive prostate seed implant patients were imaged with axial MR and CT scans. MR and CT images were fused in three dimensions using the Pinnacle 3.0 version of the ADAC treatment planning system. The urethra and bladder base were used to "line up" MR and CT image sets during image fusion. Alignment was accomplished using translation and rotation in the three ortho-normal planes. Accuracy of image fusion was evaluated by calculating the maximum deviation in millimeters between the center of the urethra on axial MR versus CT images. Implant quality was determined by comparing dosimetric results to previously set parameters. RESULTS: Image fusion was performed with a high degree of accuracy. When lining up the urethra and base of bladder, the maximum difference in axial position of the urethra between MR and CT averaged 2.5 mm (range 1.3-4.0 mm, SD 0.9 mm). By projecting CT-derived dose distributions over MR images of soft tissue structures, qualitative and quantitative evaluation of implant quality is straightforward. CONCLUSIONS: The image-fusion process we describe provides a sophisticated way of assessing the quality of a prostate seed implant. Commercial software makes the process time-efficient and available to any clinical practice with a high-quality treatment planning system. While we use MR to image soft tissue structures, the process could be used with any imaging modality that is able to visualize the prostatic urethra (e.g., ultrasound).

Arytenoid sparing during irradiation of early stage vocal cord cancer.

PURPOSE: Optimal position of the posterior field border when irradiating early stage vocal cord cancer is controversial. Several experts recommend moving the posterior field border 5-15 mm anteriorly after 50-60 Gy to decrease the chance of arytenoid edema. This article will evaluate the effect of field position on arytenoid dose. METHODS AND MATERIALS: 5 x 5 cm opposed lateral fields centered on the glottis were set up on a patient with typical anatomy. Isodose profiles were obtained with equally weighted 6 MV photon beams attenuated with 15 degree wedge filters using contours from an axial CT scan. Profiles with the posterior field border overlaying, 5, and 10 mm posterior to the posterior edge of the thyroid cartilage are presented. RESULTS: With the posterior field border 10 mm posterior to the thyroid cartilage, the arytenoids are included in the 95% isodose volume. Reducing the field by 5 mm has no significant effect on the position of the 95 and 90% isodose lines relative to the arytenoids. A field reduction of 10 mm places the arytenoids in the beam penumbra and leaves approximately 10 mm between the 95% isodose line and the midpoint of the true vocal cord. CONCLUSION: To achieve a significant dose differential between the arytenoids and the anterior portion of the vocal cord when using opposed lateral 6 MV photon beams the posterior field border must be at, or anterior to, the posterior edge of the thyroid cartilage. In view of the excellent results reported from institutions that include the arytenoids in the high-dose volume throughout treatment, it would seem appropriate to limit the use of arytenoid-sparing techniques to patients in whom there is no ambiguity about tumor location and in whom the treatment setup is very reproducible.

Tissue-shrinkage correction factor in the calculation of prostate cancer volume.

Many studies that have calculated prostate cancer volumes from microscopic slides have used correction factors, ranging from 1.22 to 1.5, to compensate for tissue shrinkage during tissue processing. We undertook a study to measure tissue shrinkage directly because our experience suggested less shrinkage than that reported by others. Ten prostatectomy specimens were processed in a uniform manner. Multiple identical linear measurements were taken at four stages of processing: in the fresh state, following fixation, following processing, and from the microscopic slide. Linear shrinkage following fixation was minimal (4.1%) but increased to 14.5% following tissue processing. With rehydration and expansion on the flotation bath, tissues swelled so that net linear tissue shrinkage was 4.3%, and net volumetric tissue shrinkage was 12.4%, which translates into a correction factor for tissue shrinkage of 1.14. The following variables had no statistically significant effect on shrinkage: concentration of formalin, whole-mount versus quadrant sections, thickness of tissue slices, length of time in the alcohol dehydration steps, and temperature of the flotation bath over a range of 35 to 45 degrees C. This study suggests that (a) tissue-shrinkage correction factors that have been used in some previous studies may not be applicable for all laboratories because of interlaboratory variations in tissue-processing procedures or differences in measuring shrinkage; and (b) some calculated tumor volumes that have been used for prognostic thresholds may be high because of inflated tissue-shrinkage correction factors.

Pneumopericardium associated with bronchogenic carcinoma.

A case of pneumopericardium associated with primary bronchogenic carcinoma is reported. This association between bronchogenic carcinoma and pneumopericardium has not been reported. The roentgenographic features of pneumopericardium are discussed.

Integrated optical surface plasmon resonance immunoprobe for simazine detection.

This paper presents the detailed design and characterisation of a regenerable integrated optical surface plasmon resonance immunoprobe as a detector for the triazine herbicide simazine. A sensor design theoretically optimised for use in the aqueous environment is presented and its fabrication described. Experimental results on the sensitivity to changes in bulk refractive index of the analyte and on non-specific binding of ovalbumin are presented. Binding inhibition immunoassays were conducted for simazine and the lower limit of detection determined to be 0.16 microgram/l using anti-simazine IgG antibodies and 0.11 microgram/l using anti-simazine Fab fragments. A sample test cycle of 20 min was established.

Unusual cause for recurrent Cushing syndrome and its diagnosis by computed tomography and NP-59 radiocholesterol scanning.

Cushing syndrome can recur following an adrenalectomy. One of the primary causes is recurrence of adrenal carcinoma either locally or from metastases. Hyperplasia and hyperfunction of adrenal remnants may also occur if there is pituitary stimulation. We have a patient in whom recurrent Cushing syndrome developed from small nonmalignant deposits of adrenal tissue in the perirenal adipose tissue following adrenalectomy of a benign adenoma. These deposits were identifiable by computed tomography. A false-negative NP-59 iodocholesterol scan was instructive in pointing out some problems in the interpretation of this type of scan for adrenal tissue.

Ureteral changes in Gardner's syndrome simulating retroperitoneal fibrosis.

The development of desmoid tumors in patients with Gardner's syndrome may produce ureteral findings on excretory urogram which, by themselves, are indistinguishable from other causes of retroperitoneal fibrosis.

Computed tomographic diagnosis of renal infarction.

Two cases of renal infarcts diagnosed on CT scans are presented which demonstrate findings that should be identifiable and diagnostic to indicate renal infarction. The examination is more reliable and specific if it is performed after the administration of intravenous radiographic contrast material. The contrast can be given either by a bolus or an infusion injection. The findings after contrast-enhanced scan should be specific enough to identify the cause of the patient's symptoms. A percutaneous CT guided biopsy can be performed to confirm the diagnosis.

Value of computerized tomography in evaluation of kidney.

The use of intravenous iodinated contrast material after a preliminary computerized axial tomographic scan of the kidney has been an extremely valuable adjunct in differentiating benign, malignant, and some inflammatory processes. The diagnosis of type of lesion present has been facilitated and allows direction for further diagnosis and therapy.

Renal arterial injury associated with percutaneous nephrostomy.

A case of pseudoaneurysm and subcapsular hematoma as a complication of a percutaneous nephrostomy with unusual clinical findings is presented. Bleeding following a closed nephrostomy must be kept in mind as a potential hazard. Computerized tomography (CT) examination should be performed in such cases using intravenous radiographic contrast material whenever possible to identify the potential bleeding site rapidly.

Percutaneous nephroscopy using fiberoptic bronchoscope: removal of renal calculus.

A method for percutaneous removal of renal calculus within the collecting system is presented. Thus utilized, a flexible fiberoptic bronchoscope with fluoroscopic guidance provides a safe and quick alternative treatment to reoperative surgery for retained renal calculi.

Computed tomographic evaluation of pear-shaped bladder.

Computed tomography (CT) was used to distinguish between pelvic lipomatosis and idiopathic inferior vena caval thrombosis as a cause of a pear-shaped bladder seen on intravenous urography. The findings on CT were explicit in explaining the patient's clinical problem.

MR imaging of corpus callosotomy.

MR findings in 13 patients who underwent corpus callosotomy for medically intractable seizures were reviewed. Preoperative MR studies were available in nine patients: five showed at least one morphological and/or MR signal abnormality including corpus callosal thinning (four cases), cerebellar atrophy (two cases), cortical atrophy (two cases), and periventricular hyperintensity on T2-weighted images (one case). Four patients had normal MR studies. Postoperative MR studies were obtained in 11 patients with subtotal callosotomy and two with total callosotomy. Of all pulse sequences, sagittal T1-weighted images best showed the surgical division, although two cases displayed a coaptation artifact, which was misleading. A surgical clip placed at the posterior extent of the callosotomy was best visualized with sagittal T1-weighted imaging. Two patients (15%) had MR findings consistent with subacute blood in the callosum, and three patients (23%) demonstrated parafalcial hyperintensity on T2-weighted images 1 week after callosotomy. Motion artifact was a significant problem with coronal imaging and T2-weighted pulse sequences in postoperative patients. Patients selected for corpus callosotomy may have a normal baseline MR or show nonspecific abnormalities. MR imaging is an effective method for evaluating callosal division, and in some cases, may demonstrate signal changes consistent with surgically related edema and/or blood.

The Beirut terrorist bombing.

The Beirut terrorist bombing on October 23, 1983, caused 234 immediate deaths and injured at least 112 survivors. Military medical records were available for each casualty; postmortem examination reports were available for each immediate fatality. This represented a unique opportunity to assess type, incidence, treatment, and outcome of neurological injuries suffered in a mass casualty terrorist bombing situation. Three categories of neurological injuries are described: head injuries, spine and spinal cord injuries, and peripheral nerve injuries. The following types and numbers of injuries occurred among the 112 immediate survivors of the explosion: 37 head injuries--28 concussions, 20 scalp lacerations, 13 skull fractures, 6 facial bone fractures, 4 cerebral contusions, 5 dural lacerations, 2 cerebrospinal fluid fistulas, and 2 intracerebral hematomas; 2 spine or spinal cord injuries--1 cervical and 1 thoracolumbar spine fracture associated with neurological deficit; and 9 peripheral nerve injuries--1 facial nerve palsy, 2 brachial plexus palsies, 1 median and 1 radial nerve palsy, and 4 peroneal nerve palsies. Among 234 immediate fatalities, the types and numbers of neurological injuries were: 167 head injuries--93 scalp lacerations, 85 skull fractures, and 24 facial bone fractures; and 22 spine and spinal cord injuries--15 cervical and 7 thoracolumbar fractures. Seven of the 112 immediate survivors died; 4 of these deaths were related to severe head injuries. The treatment and outcome of survivors with neurological injuries is briefly described. One-third of the immediate survivors who suffered either a scalp laceration or a concussion had a concomitant skull fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Unusual metastasis to the cauda equina: case report.

A case of intradural metastasis from endometrial carcinoma to the cauda equina is presented. The clinical presentation and radiographic findings were misleading and suggested a herniated nucleus pulposus. Findings at operation were most suggestive of an ependymoma, but final pathological diagnosis revealed endometrial carcinoma. This has never been reported. Once again it demonstrates that surgeons managing lumbar disc disease must be prepared for possible intradural exploration with an appropriate team.

Combined embolization and operation in the treatment of cervical arteriovenous malformations.

The effectiveness of a combined approach of embolization and operation for cervical vascular malformations is stressed. Lesions that seem to be inoperable may have their blood flow sufficiently reduced by preoperative embolization to allow surgical extirpation. Polyvinyl alcohol foam is an ideal embolic agent; not only may it be used preoperatively, but its permanency allows it to be used for primary therapy.

Prolactin suppression of leukocyte chemotaxis in vitro.

Leukocyte chemotaxis in vitro was studied for cells from patients with pituitary adenomas. Leukocytes obtained preoperatively from two of three patients with elevated serum prolactin levels demonstrated chemotaxic alterations described in other malignant disease. Statistically significant suppression of chemotaxis occurred in the leukocytes of four of 12 specimens from normal donors at concentrations of 1000 ng/ml, and in four of eight specimens at 2000 ng/ml of prolactin in preincubation media. Thus prolactin concentration may influence the motility of leukocytes. The variable neoplastic behavior of morphologically similar pituitary adenomas may, in part, reflect a neurohormonally altered host response to the presence of these lesions.