The influence of perceptions and beliefs of civilian physiotherapist working for the Ministry of Defence in their management of back pain: an exploratory study using mixed methods.

BACKGROUND: There is a high prevalence of Lower Back Pain (LBP) within military populations. Physiotherapeutic management has a primary role for patient care, but there is a need to establish the most effective management. Civilian physiotherapists provide the majority of clinical provision throughout the Defence Medical Rehabilitation Programme for British Armed Forces personnel. To date no study has been carried out looking at their perceptions and beliefs with regards to management of non-specific LBP and the potential impact this had on the delivery of rehabilitation across Defence. METHODS: This mixed methods exploratory study aimed to explore the potential complexities surrounding the decision making process with regards to management of non-specific LBP using semi-structured interviews with 14 MOD civilian physiotherapists. All interviews were transcribed verbatim. The transcribed data was then subjected to a categorical content analysis. RESULTS: The analysis of the interview data revealed four interrelated themes that influence civilian physiotherapists in their management of back pain in military personnel: the military environment, integration of military procedures, physiotherapist treatment approach and communication. DISCUSSION: This paper highlights the value civilian physiotherapists place on experience when managing non-specific LBP. This experience however was gained through 'patient mileage' rather than integration of best evidence into practice. Several problems were identified in patient management including specific types of patients and their expectations and the importance of the right communication between Health Care Professionals, but also with patients.

Treatment-related morbidity and hospital league tables: experience from a national audit of radiotherapy-induced morbidity in cervical carcinoma.

Data are now available from a U.K. audit of survival and late morbidity following curative radiotherapy for cancer of the cervix treated in 1993. The complication rate per centre ranges from 0 to 67%. Although the frequency of complications following curative radiotherapy for cancer of the cervix might be considered to be an indicator of clinical performance, variation in treatment outcomes can be explained by sampling variability rather than real differences in quality of care. In the present study we have asked the question: could the disparity in complication rates between centres be no more or less than would be expected by chance? Our analysis suggests that this is the case, and for this reason it would be premature to use such outcome data to produce league tables or to assess institutional differences. Thus, ranking centres according to complication rate would not be valid, as the differences in rates observed are probably not significantly different from the national average. It is important that audit data are not used inappropriately and this analysis further highlights the need for reliable prospective collection of clinical information and the importance of considering sampling variability in interpreting the results of such studies.

TNP-470 reduces collagen and macrophage accumulation in expanded polytetrafluoroethylene tube implants.

BACKGROUND: TNP-470 is a potent angiogenic inhibitor that has been demonstrated to decrease the rate of cutaneous wound healing. This study investigated the effect that TNP-470 has upon collagen growth and macrophage infiltration into expanded polytetrafluoroethylene (e-PTFE) tube implants. METHODS: e-PTFE tubes (1.0 cm in length) were implanted into the dorsum of male Swiss-Webster mice (8-10 weeks old). TNP-470 was administered subcutaneously in doses of 0.5, 1.0, or 5.0 mg/kg for determination of hydroxyproline accumulation on day 18 after implantation. Additionally, TNP-470 was administered at 5.0 mg/kg for determination of macrophage infiltration on days 4, 8, 13, and 18 after implantation. RESULTS: Administration of TNP-470 at doses of 1.0 and 5.0 mg/kg on days 0, 2, and 4 significantly (P < 0.05) decreased hydroxyproline accumulation in e-PTFE implants on day 18 after implantation. Administration of 0.5 mg/kg of TNP-470 yielded no significant difference vs the vehicle control (P < 0.81). Additionally, administration of TNP-470 at 5.0 mg/kg on days 0, 2, and 4 significantly (P < 0.05) decreased macrophage infiltration into e-PTFE implants on day 4 after implantation. There was also a significantly (P < 0.05) increased percentage of macrophages in the e-PTFE implants on day 13 after wounding. No significant differences were observed between the experimental and control groups on days 8 and 18. CONCLUSIONS: Administration of TNP-470 significantly decreases hydroxyproline accumulation in e-PTFE implants. These data suggest that while TNP-470 is administered, macrophage infiltration is impaired; however, upon discontinuing administration, macrophage infiltration increases. Possible mechanisms to account for these findings are discussed.

Radiotherapy-related early morbidity in head and neck cancer: quantitative clinical radiobiology as deduced from the CHART trial.

BACKGROUND AND PURPOSE: Early reactions after radiotherapy for head and neck cancer may become the limiting factor in current attempts to intensify loco-regional therapy through altered fractionation or combination of radiotherapy with chemotherapy. The aim of the present study was to quantify the dependence of early reactions on the dose-fractionation used in radiotherapy and on patients' age and radiation field size. PATIENTS AND METHODS: The data analyzed are from the randomized controlled trial of CHART (continuous hyperfractionated accelerated radiotherapy) vs. conventional radiotherapy in head and neck cancer. The trial accrued 918 patients from March 1990 to April 1995. Several early morbidity items were evaluated weekly for the first 8 weeks after the start of treatment. Weekly evaluation was continued in patients with early reactions extending beyond 8 weeks. Linear regression was used to analyze the time with reactions in individual patients. Polychotomous ordinal response regression was used to analyze the peak grade of early reactions in individual patients. RESULTS: The main findings of this analysis were as follows. (1) The incidence and peak prevalence of confluent mucositis was higher after CHART than after conventional radiotherapy. Therefore, the average time spent with confluent mucositis per patient treated was significantly longer after CHART than after conventional fractionation. (2) In patients who actually developed confluent mucositis, the average duration of this grade of reaction was not significantly different after CHART compared with conventional radiotherapy. (3) Confluent mucositis developed earlier after the start of treatment (2.9 vs. 4.9 weeks) but also started to improve sooner (5.4 vs. 7.5 weeks after the start of treatment) after CHART than after conventional radiotherapy. (4) The dose recovered per 1-day protraction of overall treatment time, D(prolif), was estimated at 0.80 Gy with 95% confidence limits 0.7 and 1.1 Gy/day for human mucosa. (5) For human skin erythema, the estimate of D(prolif) was 0.12 Gy/day with 95% confidence limits -0.12 and 0.22 Gy/day. (6) Highly significant relationships were found between the grade of morphological mucositis on one hand and dysphagia, pain on swallowing and prescribed analgesics on the other. Patients with confluent mucositis had fewer functional problems if this was confined to the larynx as compared with other subsites in the head and neck. (7) Although the incidence of confluent mucositis was higher in the oral cavity and oropharynx than in the hypopharynx and larynx, the radiobiological properties of mucosal reactions did not show significant variation among the various subsites within the head and neck region. (8) For a given dose and overall treatment time, a highly significant increase in incidence and severity of both mucositis and erythema was seen with increasing field size. Thus, a significant dose-volume or dose-area effect exists for both of these tissues. (9) Patients' age had no significant influence on the incidence and severity of mucositis or erythema. CONCLUSIONS: This study provides quantitative estimates of the dose-time and dose-volume relationships for human skin and normal mucosa in the head and neck region based on an analysis of data from 918 patients entered into a randomized-controlled trial of altered dose fractionation in radiotherapy.

Predictors of acquiring a nosocomial bloodstream infection on extracorporeal membrane oxygenation.

PURPOSE: The aim of this study was to identify independent predictors of acquiring a nosocomial bloodstream infection (BSI) during extracorporeal membrane oxygenation (ECMO). METHODS: This retrospective cohort consisted of 202 neonates treated with ECMO from 1989 to 1998 at the author' institution. Data collected included patient demographics, primary and secondary diagnoses, white blood cell counts, antibiotic usage, presence of central lines, operative procedures, and outcome. Surveillance blood cultures were drawn daily from the circuit using sterile technique to identify acquired pathogens. Statistical analyses included logistic regression, Cox proportional regression analysis, and discriminate analysis. RESULTS: There were 1,245 blood cultures drawn on 202 patients (6.2 cultures per patient), and a nosocomial BSI was identified in 7 patients (3.4%) during this 10-year span. These were infections that were neither present nor incubating on admission. Pre-ECMO diagnoses of patients who had a nosocomial BSI while on bypass included group B beta-hemolytic streptococcal sepsis (n = 2), herpes simplex viral sepsis (n = 1), congenital diaphragmatic hernia (n = 2), persistent pulmonary hypertension (n = 1), and congenital heart disease (n = 1). The median time on ECMO before obtaining a positive culture was 390 hours. The infectious agents responsible for these BSIs included Staphylococcus epidermidis (n = 5), Staphylococcus aureus (n = 1), and Escherichia coli (n = 1). The major factor associated with acquiring a nosocomial BSI on ECMO was the duration of bypass (391 v 141 hours, P =.002). Additionally, patients in the BSI group were more likely to have had an arterial catheter in place (16 v 7 days, P =.009) and to have received more screening blood cultures (16 v 6 cultures, P < 001). White blood cell counts, absolute neutrophil counts, and immature/total (I/T) ratios were not useful in predicting a nosocomial BSI. Of the 31 patients who required ECMO for more than 10 days, 7 (23%) had a positive blood culture, and 5 of these 7 infants (71%) died (P =.03). CONCLUSIONS: The only predictor of acquiring a nosocomial BSI on ECMO was the duration of support for greater than 10 days. Because classical predictors of infection are unreliable while the patient is on ECMO, the authors suggest that obtaining daily surveillance blood cultures beginning on the tenth day should be performed with prolonged ECMO courses. The authors confirmed previous reports of the association between a prolonged ECMO course and a high mortality rate. However, the authors speculate that, in actuality, the primary diagnosis leads to the prolonged course of support and is the major factor in the infant' demise.

Interaction of angiogenesis inhibitor TNP-470 with basic fibroblast growth factor receptors.

TNP-470 is a synthetic analogue of fumagillin that acts as a potent angiogenesis inhibitor. Recently, our laboratory demonstrated that systemic administration of TNP-470 (5.0 mg/kg) decreased the rate of cutaneous wound healing by greater than 20%. In this study, we tested the hypothesis that TNP-470 interferes with the wound repair-stimulating action of basic fibroblast growth factor (bFGF) by competing with endogenous bFGF for its binding sites on the receptor protein. The influence of TNP-470 was examined in vitro in a ligand competition assay of high- and low-affinity receptor binding to (125)I-bFGF in NIH/3T3 cells. Results demonstrated that recognition of (125)I-bFGF by low-affinity growth factor binding sites was significantly decreased (P < 0.01) in the presence of TNP-470. However, TNP-470 inhibition of radiolabeled bFGF binding to high-affinity sites was not significantly affected (P = 0.07). In view of recent studies demonstrating that the low-affinity receptors of bFGF were heparan sulfate proteoglycans, we suggest that the influence of TNP-470 on diminished wound healing is due to its direct recognition by these molecules.

Clinical radiation doses for spinal cord: the 1998 international questionnaire.

BACKGROUND AND PURPOSE: Emmanuel van der Schueren gave a keynote lecture at the 1988 ASTRO annual conference pointing out that the spinal cord 'tolerance doses' then prescribed were probably unnecessarily cautious, resulting in probable underdosing of some tumours. This lecture was supported both by an international questionnaire which he and two of the present authors had conducted, and by animal experimental data. In 1997 he initiated a 10-year follow-up questionnaire, the results of which are summarised here. MATERIALS AND METHODS: The present report analyses the change in prescriptions from 1988 to 1998 and the variation in prescriptions among various regions of the World. RESULTS AND CONCLUSIONS: The main conclusion is that prescribed dose levels have increased significantly in this period. Large geographical variations still exist. Among responders who use a formula to correct for changed dose per fraction, 90% are now using the linear-quadratic model vs. 33% in 1988. The current status of clinically acceptable doses to spinal cord in 2-Gy fractions is discussed briefly. Further details from the responses to the 1998 questionnaire will be presented in another publication.

Selection of active drugs for ovarian cancer based on CA-125 and standard response rates in phase II trials.

PURPOSE: To determine whether precise definitions of response based on serial CA-125 levels can predict the activity of drugs in phase II trials for ovarian cancer as accurately as standard criteria. PATIENTS AND METHODS: Fourteen different drugs for relapsed ovarian cancer were analyzed in 25 treatment groups in 19 clinical trials. Response rates were estimated in 1,457 assessable patients according to standard criteria and in 1,092 assessable patients according to CA-125. For each drug trial, the observed response rates acted as the input data for an evaluation of how the two criteria would perform in a hypothetical Gehan two-stage phase II trial, accepting a target drug efficacy rate of 20% and a rejection error of 5%. RESULTS: CA-125 and clinical response criteria were concordant in 20 of the 25 groups, with less than 5% chance of rejecting the drug in nine groups and greater than 5% in 11 groups. In four groups, the drug had less than 5% chance of being rejected by CA-125 but greater than 5% chance of being rejected by standard criteria. The difference in the classification of drugs by the standard and CA-125 response criteria was not statistically significant (P =.38, McNemar's test). CA-125 response rates were slightly higher than standard response rates by a factor of 1.11. CONCLUSION: Definitions based on a 50% or 75% decrease of CA-125 levels accurately predicted which drugs in phase II trials for relapsed ovarian cancer were active and justified further investigation.

National audit of the management and outcome of carcinoma of the cervix treated with radiotherapy in 1993.

The aim of the study was to investigate the UK prevalence of late, severe side-effects associated with radical radiotherapy for cancer of the cervix and try to identify associated factors. All patients treated for cancer of the cervix with radical radiotherapy in 1993 were identified and retrospective case notes studied to determine mortality and severe complications occurring following treatment. Of the 55 radiotherapy departments in the UK that were treating gynaecological malignancy in 1993, 53 participated in the study. There were 1558 patients with carcinoma of the cervix receiving radical radiotherapy as part of their treatment regimen in 1993, whose patterns of treatment were assessed. The main outcome measures were the development of late severe complications as defined by the Franco-Italian Glossary and mortality. Of the patients receiving surgery and radiotherapy, 58.5% underwent Wertheim's procedure. The crude rate of late severe complications in all patients with cervical cancer treated with radical radiotherapy in 1993 was 6.1% (actuarial rate 8%) at 5 years, and only four of the 91 patients who developed complications died as a result of their morbidity. There was no significant correlation of stage, centre size, surgery or radiotherapeutic approach with late morbidity in univariate analysis. The overall survival at 5 years was 47% and was lower than that of the European data from FIGO's 1990-92 cohort, for all stages. Increasing FIGO stage was the only factor significantly associated with mortality. The absence of variables that were significantly associated with late complications may well be related to the relatively low event rate compared to the sample size. Differences in surgical treatment prior to radiotherapy and radiation technique may be confounding the comparison of outcomes. The relatively poor survival for locally advanced disease and the difficulty with which these data were collated indicates that national prospective data collection is urgently required to monitor performance and hence derive best practice.

Angiogenesis inhibitor TNP-470 inhibits murine cutaneous wound healing.

BACKGROUND: TNP-470 (AGM-1470) is a potent inhibitor of angiogenesis with potential therapeutic applications in neoplastic and angio-proliferative diseases. This study evaluated its effect on cutaneous wound healing in a murine dorsal excisional wound model. MATERIALS AND METHODS: Full-thickness wounds (1.60 cm2) were created on the dorsum of homozygous/hairless mice (7 to 9 weeks). Wound areas were measured on alternate days for 16 days. Experimental groups consisted of (1) TNP-470 administered in doses of 0.05, 0.5, and 5.0 mg/kg on Days 0, 2, and 4 or Days 0 through 6; (2) TNP-470 (5.0 mg/kg) coadministered with minocycline (4.0 and 10 mg/kg) on Days 0, 2, and 4; and (3) TNP-470 (5.0 mg/kg on Days 0, 2, and 4) coadministered with topical basic fibroblast growth factor (bFGF) 1. 0 microg/wound on Days 0, 1, and 2. Hematoxylin and eosin staining was used to compare experimental and control wounds. RESULTS: TNP-470 administration significantly decreased wound healing in a dose-dependent manner versus controls (P <.05). The 5.0 mg/kg concentration yielded the greatest effect by maintaining an average wound area 20.4% greater than controls and a marked delay in wound healing on H&E staining. Alternate-day dosing was as effective as consecutive day administration. Minocycline did not augment the wound healing inhibition of TNP-470. Coadministration of TNP-470 and bFGF eliminated any rate-altering effect of TNP-470 upon wound healing and resulted in wound areas similar to controls. CONCLUSION: Therapy with TNP-470 induces a significant delay in murine cutaneous wound healing. This effect may be exploited for use in situations where wound healing is excessive and debilitating. Topical application of bFGF can overcome TNP-470-induced wound healing inhibition.

Evaluation of post extracorporeal membrane oxygenation follow-up testing.

The purpose of this study was to evaluate all post extracorporeal membrane oxygenation (ECMO) tests for their ability to detect any change in the incidence of unanticipated medical problems, and their charge to the patient. The current post ECMO protocol consists of the following tests: brain stem auditory evoked response, head computed tomography, cerebral blood flow, head ultrasonography, electroencephalography, eye examination for retinopathy of prematurity, and pneumocardiography. A retrospective review was conducted for all surviving neonatal ECMO patients treated from January, 1985, to December, 1994. The results of each test were classified as either normal, having a minor abnormality, or having a major abnormality. Statistical analyses were performed on each test comparing the incidence of minor and major abnormalities to all neonates in the neonatal intensive care nursery. Two hundred ninety-six infants survived their course on ECMO, and composed the study population. There were no significant differences between the incidence of abnormal results compared with the expected values for the following tests: cerebral blood flow (p=0.13), the eye examination (p=0.54), and pneumocardiography (p=0.22). The analyses for the brain stem auditory response, head computed tomography, head ultrasonography, and electroencephalography showed higher than expected incidences of abnormal results (p < 0.01). The data also were evaluated for major abnormalities on computed tomography and head ultrasonography. Of 161 infants who had both tests performed, 11 (6.8%) had normal head ultrasonography results, yet had a major abnormality noted on computed tomography (p < 0.01). This study is the first to review the current post ECMO protocol comprehensively, and the results suggest excluding the cerebral blood flow, eye, and pneumocardiography tests. This would result in a significant savings of $1,400 without compromising patient care. In addition, comparisons of neuroradiographic studies indicate that computed tomography of the head is sensitive enough to detect all central nervous system abnormalities that were found by ultrasonography. Excluding the post ECMO head ultrasonography, an additional savings of $300 would occur. These recommended changes reflect the current post ECMO protocol at Kosair Children's Hospital.

Complicated cannula insertions and cannula dislodgments associated with extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation therapy remains a life saving modality for neonates with cardiopulmonary disease that is unresponsive to conventional therapy. Vital to its success is the insertion and maintenance of appropriately sized vascular cannulas. Problematic insertion and accidental dislodgments can be life threatening. To determine the treatment and outcome of these complications, a survey of participating Extracorporeal Life Support Organization centers was undertaken. Venous cannulation complications (13 patients) were due to inadequate vein size or tearing during initial attempts at cannulation. Proximal and alternative site cannulation were used. Difficult arterial cannulations (seven patients) were most often due to creation of an intimal flap that was corrected by proximal cannulation of the same vessel. The 10 cases of accidental dislodgment were most often associated with changes in position. Despite copious hemorrhage in many instances, 6 of 10 patients survived with intact neurologic status. Methods for dealing with these life threatening cannula related complications are described.

Cutaneous burns caused by sulfuric acid drain cleaner.

BACKGROUND: Highly concentrated solutions of sulfuric acid are available to unclog drains. We have noted a substantial number of both accidental and intentional cutaneous burns caused by these agents. METHODS: A retrospective review was conducted of children and adults who sustained sulfuric acid burns over a 13-year period ending in May 1996. Reports of injuries related to drain cleaners filed with the United States Consumer Product Safety Commission between 1991 and 1995 were also reviewed. RESULTS: Twenty-one patients (13 children, 8 adults) sustained cutaneous burns caused by concentrated sulfuric acid solutions. In 8 instances, the burn was accidental, whereas in 13 cases, sulfuric acid was used as a weapon. Median total body surface area burned was 5% (range, 1-25%). Approximately 50% of burns involved the face and neck. Skin grafting was required in 14 patients (66%). It is estimated that nationwide approximately 3,000 injuries per year are related to drain cleaners and that one-third of these involve cutaneous burns. CONCLUSION: Highly concentrated sulfuric acid drain cleaner can produce full-thickness cutaneous burns that require skin grafting in the majority of cases. Proper use of these agents and sequestering them from children may reduce accidental contact; however, their abuse as agents of assault remains a source of significant morbidity.

Retaining extracorporeal membrane oxygenation cannulae after extracorporeal support in the neonate: is it safe?

The retention of extracorporeal membrane oxygenation (ECMO) cannulae of ECMO is discontinued was originally developed to avoid reexploration of the neck in patients who may require a second course of ECMO. Because of the incidence, at the authors' institution, of thrombi noted on the ends of retained cannulae and their potential to cause significant morbidity, a critical review of this procedure was initiated. A telephone survey of 72 Extracorporeal Life Support Organization (ELSO) centers was conducted, and ELSO registry forms were requested for patients who had their cannulae retained. Twenty-four of these centers had performed the procedure of retaining ECMO cannulae. There were 324 neonatal and pediatric patients who had their cannulae retained, with 41 patients (12%) requiring a second course of ECMO and 17 of 41 (41%) surviving the second course. Twelve of the 24 ELSO centers that retain cannulae have reported complications. Analyses of the patients who had their cannulae retained showed that the three best predictors for requiring a second course of ECMO were the diagnosis of congenital diaphragmatic hernia (CDH) a high oxygenation index just before the initiation of ECMO, and a lengthy first ECMO course. The only difference between the survivors and nonsurvivors of the second course of ECMO was the length of the first ECMO course (P < .05). Five of the 25 patients who required two courses of ECMO had serious complications from their retained cannulae and all were nonsurvivors. The authors conclude that patients with retained ECMO cannulae are at high risk for developing thrombi, which can lead to severe embolic events. Therefore, the procedure of retaining cannulae should only be used in patients at high risk for requiring a second course of ECMO and not for the convenience of surgical availability to remove the cannulae.

Survival of patients with congenital diaphragmatic hernia during the ECMO era: an 11-year experience.

BACKGROUND/PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with significant mortality and morbidity. To evaluate the impact of extracorporeal membrane oxygenation (ECMO) on survival, a review of our experience with CDH patients was initiated. METHODS: The authors performed a retrospective nonrandomized analysis of 98 consecutive CDH patients who were ECMO candidates, and were symptomatic within the first day of life, and underwent repair between May 1985 and May 1996. The patients were divided into three groups: Group 1 (n = 38) refers to patients who were clinically stable and underwent repair before 48 hours of age and did not need ECMO rescue; Group 2 (n = 29) consists of patients who underwent repair but required ECMO rescue; and Group 3 (n = 31) refers to patients who met ECMO criteria preoperatively and required ECMO for stabilization and later underwent repair on ECMO. The Kaplan-Meier survival graph was used for survival analysis. RESULTS: During the 11-year span, the overall survival rate of all CDH patients was 72% (71 of 98). The survival rate of patients who did not require ECMO support was 92% (35 of 38), whereas patients who required ECMO after repair had a 72% (21 of 29) survival rate. These were compared with a 48% (15 of 31) survival rate for those undergoing repair on ECMO. The differences in survival among the three groups were statistically significant using the log-rank test (P = .0018). CONCLUSIONS: Survival was significantly better for infants who underwent successful repair without ECMO than those who required ECMO rescue pre- or postrepair. The overall improved survival of CDH patients to 72% compared with historical controls of 38% to 58% may be attributed to ECMO, but the requirement of ECMO before repair, as well as the presence of congenital anomalies (P < .01), prematurity (P < .01), the need for a Gore-Tex patch at repair (P < .05), prenatal diagnosis at less than 25 weeks' gestation (P < .01), and the occurrence of an intracranial hemorrhage (P < .01), decreases the chances of survival.

Air-powered guns: too much firepower to be a toy.

OBJECTIVE: This study reviews our experience and calls attention to the potential danger of air-powered guns. DESIGN: Retrospective analysis. MATERIALS AND METHODS: Review of patients with air-powered gun-injuries admitted to a Level I trauma center and air gun deaths reported to the United States Consumer Product Safety Commission over a 5-year period ending July 1994. RESULTS: Sixteen children (median age 10) were admitted after sustaining BB or pellet gun injuries. Three children had cranial penetration; one remains severely brain impaired. One of two thoracic injuries required left ventriculorrhaphy. All five children sustaining abdominal wounds underwent laparotomy for enteric perforations; one was complicated by an intra-arterial pellet embolus. Three of five children with neck wounds had penetrating tracheal injury. Overall nine children required operative intervention. No deaths occurred in our series, but there were 33 air gun deaths reported to the United States Consumer Product Safety Commission during this period. CONCLUSION: Our data demonstrate that injuries from air-powered guns should be treated in a manner similar to those from low velocity powder firearms. We can no longer continue to underestimate the potential for life-threatening injury from these weapons.

Open lung biopsy in pediatric patients on extracorporeal membrane oxygenation.

Open lung biopsy has proven beneficial in the treatment of life-threatening pulmonary diseases. Its safety and efficacy in infants and children placed on extracorporeal membrane oxygenation (ECMO) for severe respiratory failure is not known. The authors reviewed eight cases (4 neonates, 3 infants, 1 child) who underwent open lung biopsy while on ECMO. The primary diagnoses were pneumonia (4), lymphoma (1), primary pulmonary hypertension (1), and complex congenital heart disease (2). The patients underwent biopsy after they had been on ECMO an average of 9.6 days (range, 1 to 14 days). Biopsy results confirmed the clinical diagnosis in five patients, two of whom had irreversible alveolar destruction resulting in ECMO withdrawal. Three patients had pathological diagnoses, which resulted in major therapy revisions (1 fungal infection and 2 noninfectious lesions that required steroid treatment). The overall average duration of ECMO treatment was 16.3 days (range, 10 to 24 days). Three patients were weaned successfully from ECMO, but only one infant survived to discharge. One nonlethal bleeding complication occurred after biopsy. Open lung biopsy is well tolerated during ECMO. It accurately determines pulmonary pathology and provides valuable prognostic information. Earlier biopsy for patients whose diagnoses are uncertain or who are not responding to ECMO may improve the mortality rate for this high-risk group.

Use of two-dimensional and contrast echocardiography for venous cannula placement in venovenous extracorporeal life support.

The objective of this study was to determine the efficacy of two-dimensional and contrast echocardiograms to identify venous cannula position. Sequential sampling of 20 infants was evaluated by contrast echocardiography after meeting institutional criteria for extracorporeal life support. Each infant was placed on venovenous extracorporeal life support using a double-lumen cannula. After surgical placement was thought to be satisfactory, optimal two-dimensional images of the cannula were obtained via a subxiphoid or apical view and 2 ml agitated normal saline were injected rapidly into the nearest infusion port. Patient demographics and mixed venous saturations were noted. Distance of the venovenous cannula to tricuspid valve and distance of the venovenous cannula from the intra-atrial septum was recorded. Echocardiograms were available for review on 18 of the 20 patients. Position of the venovenous cannula in relationship to the tricuspid valve was as follows: < 5 mm (8); 5-10 mm (5); > 10 mm (5). Mixed venous saturations decreased, which indicated less recirculation when the orientation of the tip of the cannula was toward the lateral wall in those who required repositioning. The authors conclude that two-dimensional and contrast echocardiography aid in the positioning of the venovenous cannula. Satisfactory position is approximately 5 mm from the tricuspid valve, with orientation toward the lateral wall of the right atrium.

The use of a second course of extracorporeal membrane oxygenation in neonatal patients.

Extracorporeal membrane oxygenation (ECMO) has been successful in rescuing near term or term infants in cardio-respiratory failure that results from a reversible disease process. In most cases, only one course of ECMO is needed to save these infants. However, a second course of ECMO may be beneficial in a select group of infants when recurrent persistent pulmonary hypertension develops. Other than abstract form, this is the first report of the use of a second course of ECMO in the literature. The authors report on three infants, two with recurrent persistent pulmonary hypertension secondary to congenital diaphragmatic hernia and one with necrotizing tracheobronchitis after Group B streptococcal sepsis who were treated at their institution with a second course of ECMO. Technical considerations in using a second course of ECMO depend upon the initial vessel cannulation site, time elapsed between cannulations, and the condition of the original artery and vein. By adopting a stenting procedure in those infants whose initial trial off was equivocal, a second cannulation may be prevented in neonatal patients with recurrent persistent pulmonary hypertension.