Exploring pressures, tissue reperfusion and body positioning: a pilot evaluation.

OBJECTIVE: To assess the relationship in healthy adults and critically ill patients between: patient position, body mass index (BMI), patient body temperature, interface pressure (IP) and tissue reperfusion (TR). Also to determine the relationship in critically ill patients between: Sequential Organ Failure Assessment (SOFA) score, Braden Scale score for predicting pressure injury risk, Acute Physiology and Chronic Health Evaluation II (APACHE II) severity of disease classification score, IP and TR. METHODS: This study took place in a 27-bed intensive care unit (ICU) of an Australian tertiary hospital. IP and TR outcomes were measured at the sacrum and greater trochanter. Repeated measures analyses of variance (ANOVAs) and doubly multivariate repeated measures ANOVAs were conducted using peak pressure index (PPI), peak time (PT), settled time constant (STC) and normalised hyperaemic area (NHA) measures of TR as outcomes. Participant type, body mass index (BMI), Braden and APACHE II scores and patient body temperature were considered as between-groups factors and covariates. RESULTS: We recruited 23 low- and high-acuity ICU patients and nine healthy adult volunteers. Not all IP readings could be obtained from ICU patients. TR readings were collected from all recruited patients, but not all TR measurements were mutually uncorrelated. Controlling for age, PPI readings differed between participant types (p=0.093), with the highest values associated with high-acuity patients and the lowest with healthy adults; the association was not substantive when controlling for age and BMI. Age was a significant variable (p=0.008), with older participants having higher scores than younger ones. No statistically significant associations between any measured parameter and TR variables were observed. However, temperature was revealed to be related to TR (p=0.091). CONCLUSIONS: Although not powered to detect significant effects, this pilot analysis has determined several associations of importance, with differences in outcomes observed between low- and high-acuity ICU patients; and between ICU patients and healthy volunteers.

WE-E-218-01: Writing and Reviewing Papers in Medical Physics.

There is an art to writing a scientific paper so that it communicates accurately, succinctly, and comprehensively. Developing this art comes with experience, and sharing that experience with younger physicists is an obligation of senior scientists, especially those with editorial responsibilities for the journal. In this workshop, the preparation of a scientific manuscript will be dissected so participants can appreciate how each part is developed and then assembled into a complete paper. Then the review process for the paper will be discussed, including how to examine a paper and write an insightful and constructive review. Finally, we will consider the challenge of accommodating the concerns and recommendations of a reviewer in preparing a revision of the paper. A second feature of the workshop will be a discussion of the process of electronic submission of a paper for consideration by Medical Physics. The web-based PeerX-Press engine for manuscript submission and management will be examined, with attention to special features such as epaps and line-referencing. Finally, new features of Medical Physics will be explained, such as Vision 20/20 manuscripts, Physics Letters and the standardized formatting of book reviews. LEARNING OBJECTIVES: 1. Improve the participants' abilities to write a scientific manuscript. 2. Understand the review process for Medical Physics manuscripts and how to participate in and benefit from it. 3. Appreciate the many features of the PeerX-Press electronic management process for Medical Physics manuscripts. 4. Develop a knowledge of new features of Medical Physics.

Cross section for b-Jet production in &pmacr;p collisions at radicals = 1.8 TeV

Bottom-quark production in &pmacr;p collisions at sqrt[s] = 1.8 TeV is studied with 5 pb(-1) of data collected in 1995 by the D0 detector at the Fermilab Tevatron Collider. The differential production cross section for b jets in the central rapidity region ( | y(b)|<1) as a function of jet transverse energy is extracted from a muon-tagged jet sample. Within experimental and theoretical uncertainties, D0 results are found to be higher than, but compatible with, next-to-leading-order QCD predictions.

Ring avulsion injuries.

BACKGROUND: Ring avulsion injuries can vary in severity from mere breach of the skin through to complete amputation or degloving. Management of the more severe injuries remains controversial in deciding whether to salvage or amputate. METHOD: Six cases managed between 1991 and 1997 are presented. RESULTS: Results were comparable to the larger series published. CONCLUSION: Referral to a microsurgical unit and attempted repair where possible are recommended.

Gastric teratoma: the sixth reported case in a female infant.

Teratomas are derived from tissues of all three germ layers. Gastric teratomas are rare and represent 1% of all teratomas in boys. This report describes the sixth occurrence of gastric teratoma in a girl.

Thoracoscopically assisted esophagectomy with gastric pull-up for esophageal cancer.

Thoracoscopically assisted esophagectomy with gastric pull-up was done in a 56-year-old man with esophageal cancer. The thoracoscopic technique, including the use of intraoperative ultrasound, is discussed. The addition of thoracoscopy offers safer and more complete esophageal dissection than transhiatal blunt esophagectomy and is less invasive than conventional thoracotomy.

Median nerve injury and the transverse wrist crease incision in open carpal tunnel release.

The author has recently had referred to him three patients with median nerve injuries who have had open carpal tunnel decompression via a small transverse wrist incision. Despite previous adverse reports, some surgeons persist with this technique.

Endoscopic carpal tunnel release. Use of the modified Chow technique in 215 cases.

OBJECTIVE: To present my experience using the modified Chow two-portal technique of endoscopic carpal tunnel release. PATIENTS: Two hundred and fifteen patients with a clinical diagnosis of carpal tunnel syndrome of more than three months' duration, unresponsive to conservative treatment. Only those few with the specific contraindications of recurrence, a florid flexor tenosynovitis or an acute crush injury were excluded. INTERVENTION: The operation used the modified Chow two-portal endoscopic method of carpal tunnel release. The original Chow method was used in another 15 patients. MAIN OUTCOME MEASURE: Symptomatic relief of pain and paraesthesia. RESULTS: Most patients made a rapid and dramatic recovery, with an early return to work, when compared with both my and patients' previous experience of open carpal tunnel release. Complications were few--two cases of mild reflex sympathetic dystrophy, two of unrelieved symptoms, and no permanent nerve or tendon injury. CONCLUSION: The modified Chow two-portal technique of endoscopic release of the carpal tunnel is effective, with a rapid recovery and few complications--provided that it is done by a surgeon experienced in this method.

Hide and seek: pre-operative ultrasonic localization of non radio-opaque foreign bodies.

Ultrasound has long been used as a diagnostic and therapeutic tool in surgery. We have extended its use to hand surgery, where is has several applications. Non radio-opaque foreign body extraction is invariably a frustrating exercise of 'hide and seek'. Accurate pre-operative localization with ultrasound illustrating size, shape, depth, soft tissue and bony relationships can ensure rapid and complete removal. Several cases are presented to demonstrate the use of ultrasound for the detection of non radio-opaque foreign bodies. The technique used will be described. We feel pre-operative localization by ultrasound is a useful technique to assist with the removal of non radio-opaque foreign bodies.

The dorsal plate of the proximal interphalangeal joint.

There exists on the articular surface of the central slip of the extensor tendon slip overlying the P.I.P. joint a constant structure which is morphologically similar to the patella of the knee joint and histologically similar to the fibro-cartilaginous palmar plate of the P.I.P. joint. It has been termed the dorsal plate. A study of 70 fingers, including 30 examined under magnification and 20 examined histologically, confirmed its constant presence and structure. Its functions appear to include stabilisation of the central extensor tendon and participation in stabilisation of the proximal interphalangeal joint.

The modified Kleinert splint in zone II flexor tendon injuries.

The Kleinert controlled passive mobilisation splint has been modified to increase the passive range of motion of the proximal and distal interphalangeal joints to near normal. 12 fingers with complete divisions of both flexor tendons in Zone II treated by this method have been reviewed after six months. Nine regained full motion and two good motion while one, with an associated crush compound fracture of the proximal phalanx, had a poor result. The increased mobilisation did not adversely affect wound healing or associated repair of digital nerves.

Surgical rehabilitation of the upper limb in quadriplegia.

Fifteen quadriplegic (tetraplegic) patients from the Spinal Injuries Unit of the Austin Hospital have had surgery to improve function in 17 of their upper limbs. Changes in strength, function, subjective ratings and the influence on 198 activities of daily living are reviewed. The posterior third of the deltoid muscle was transferred into 8 triceps tendons to provide active elbow extension in seven patients. Six patients had transfers of forearm muscles to provide grasp and lateral pinch or active extension of wrist and fingers. Other operations included transfer of the latissimus dorsi to the forearm producing elbow flexion, medial advancement of the anterior deltoid origin improving shoulder control (an operation which has not been described previously), and tenodesis for stabilizing the wrist. The objective results were satisfactory in 12 patients. Eleven patients had either good or excellent subjective results. The maximum force of active elbow extension achieved was 6.8 kg and the peak grip strength reached was 10.5 kg. Six patients achieved subjective results higher than would have been expected from objective assessment. All patients benefited in some way, 13 patients felt that surgery was worthwhile and no patient lost appreciable function. The results of this series indicate that upper limb surgery has a definite place in rehabilitation of the quadriplegic patient. Improved surgical technique may reduce the time required for postoperative rehabilitation and thus make these procedures feasible for a larger number of patients.

Analgesic and gastrointestinal effects of nalbuphine--a comparison with pethidine.

A double-blind comparison of some analgesic and gastrointestinal effects of nalbuphine and pethidine was performed in 28 women undergoing laparoscopic sterilisation. The opioid was given as an initial loading dose prior to the induction of general anaesthesia and further doses were given on demand in the postoperative period to achieve and maintain adequate pain relief. Gastric emptying in the immediate postoperative period was also assessed in each patient by measuring the rate of absorption of orally administered paracetamol. Nalbuphine was equally effective as pethidine as a postoperative analgesic, but may have been a less effective supplement to anaesthesia in the doses used in this study. Gastric emptying was profoundly depressed in all patients irrespective of which analgesic was used.

Newer methods of delivery of opiates for relief of pain.

Successful pain management using opiates requires both an analgesic with sufficient intrinsic activity and an effective administration system. Most instances of unsatisfactory pain control, however, are due to failure to achieve and maintain adequate blood concentrations of the chosen drug. Newer techniques of administration aim to overcome this problem. Oral opiate therapy with conventional or sustained-release formulations of morphine provide good control of terminal cancer pain provided that a regular dosing pattern is established and reviewed according to the patient's needs. This represents a significant departure from the traditional 'as required' prescription of this type of drug. In the management of acute severe pain, sublingual and intravenous opiates--self-administered as needed, or given by mandatory dosing schedules--have also been shown to overcome the limitations of intermittent intramuscular injections. A further novel development, stemming from basic neuroscience research, is the selective application of opiates to the spinal cord via the epidural or intrathecal route. This controversial technique has led to major improvements in treatment of some types of acute and chronic pain.