Describing the appropriate use and interpretation of odds and risk ratios.

In sport medicine, epidemiology of sport-related injury provides the foundation for understanding what types of injuries and illnesses occur and who is at the highest risk. Thus, accurate and transparent reporting and interpretation of risk metrics is essential to sports epidemiology. Odds ratios (OR) and risk ratios (RR) are two statistics used to quantify the association between exposure and outcome and are frequently seen in sports medicine literature. While similarities exist, there are optimal ways to use and interpret OR and RR based on the study design and outcome incidence in the target population. In this short communication, we will present common study designs (e.g. prospective cohort, case-control, cross-sectional) along with recommendations for the use and interpretation of OR and RR. This will ultimately assist practitioners in choosing and interpreting these frequently confused measures of association and also help journal reviewers better understand the appropriate use of these measures when evaluating a manuscript.

The diagnosis of intraabdominal visceral injury.

This article outlines the different modalities that have been used for the diagnosis of intraabdominal visceral injury. The methods span decades, and their development was driven by the need to provide an accurate and rapid diagnosis of intraabdominal injury for the patient. Some of these modalities parallel the explosion in technology. Each has been validated and criticized but eventually had developed its own "niche" in the assessment of the injured patient. Finally, they have all withstood the test of time.

Percutaneous tracheostomy: one center's experience with a new modality.

BACKGROUND: A retrospective review of our experience with percutaneous tracheostomy was performed to determine our complication rate and pattern of use since this modality was introduced at our institution. METHODS: A retrospective chart review captured all patients in whom tracheostomy was performed or supervised by a trauma/critical care faculty member. Dates of hospital admission, ICU admission, intubation, discontinuation of mechanical ventilation, type and location of procedure, procedural complications, Injury Severity Score, charges, and patient demographics were collected. Percutaneous tracheostomy (PT) and open tracheostomy (OT) experiences were compared. RESULTS: Three hundred sixty-eight tracheostomies were performed (190 OT and 178 PT). The average time to tracheostomy (TTT) for PT patients decreased from 12.7 to 7.4 days. The average TTT for OT patients remained stable at 14.0 days. The complication rate was 3.5%, with 4 complications (1.5%) associated with OT and 9 complications (5.1%) associated with PT. All complications in the PT group occurred before using a single dilator system. The 9 complications in the PT group occurred among 5 surgeons, all before their 11th attempt. PT saves 444 dollars in charges per procedure. CONCLUSION: OT continues to be a safe method of performing tracheostomies. PT has a steep learning curve but can be mastered quickly. Benefits include a shorter time to tracheostomy, elimination of patient transport, and saving in charges. Initial PT attempts should be supervised by an experienced surgeon.

Trauma surgery malpractice risk: perception versus reality.

OBJECTIVE: We set out to compare the malpractice lawsuit risk and incidence in trauma surgery, emergency surgery, and elective surgery at a single academic medical center. SUMMARY AND BACKGROUND DATA: The perceived increased malpractice risk attributed to trauma patients discourages participation in trauma call panels and may influence career choice of surgeons. When questioned, surgeons cite malpractice risk as a rationale for not providing trauma care. Little data substantiate or refute the perceived high trauma malpractice risk. We hypothesized that the malpractice risk was equivalent between an elective surgical practice and a trauma/emergency practice. METHODS: Three prospectively maintained institutional databases were used to calculate and characterize malpractice incidence and risk: a surgical operation database, a trauma registry, and a risk management/malpractice database. Risk groups were divided into elective general surgery (ELECTIVE), urgent/emergent, nontrauma general surgery (URGENT), and trauma surgery (TRAUMA). Malpractice claims incidence was calculated by dividing the total number of filed lawsuits by the total number of operative procedures over a 12-year period. RESULTS: Over the study period, 62,350 operations were performed. A total of 21 lawsuits were served. Seven were dismissed. Three were granted summary judgments to the defendants. Ten were settled with payments to the plaintiffs. One went to trial and resulted in a jury verdict in favor of the defendants. Total paid liability was 4.7 million dollars(391,667 dollars/year). Total legal defense costs were 1.3 million dollars(108,333 dollars/year). The ratio of lawsuits filed/operations performed and incidence in the 3 groups is as follows: ELECTIVE 14/39,080 (3.0 lawsuits/100,000 procedures/year), URGENT 5/17,958, (2.3 lawsuits/100,000 procedures/year), and TRAUMA 2/5312 (3.1/100,000 procedures/year). During the study period, there were an estimated 49,435 trauma patients evaluated. The incidence of malpractice lawsuits using this denominator is 0.34 lawsuits/100,000 patients/year. CONCLUSIONS: These data demonstrate no increased risk of lawsuit when caring for trauma patients, and the actual risk of a malpractice lawsuit was low.

Appendicitis: why so complicated? Analysis of 5755 consecutive appendectomies.

A perceived high rate of complicated (gangrenous or perforated) appendicitis, despite advances in laboratory and radiographic diagnostic modalities, prompted a review of our experience with appendicitis followed by a prospective analysis that examined the time course from presentation to definitive treatment in 218 consecutive patients. In 5755 appendectomies, our overall rate of complicated appendicitis was 32 per cent; higher in males, in the young, and in the elderly; and relatively stable over each year reviewed. Prospectively, we determined that of the various time intervals, the time from the onset of symptoms to first seeking medical attention is the only significant predictor of complicated appendicitis (39.8 vs 16.5 hours for acute appendicitis). On the other hand, the time from surgical evaluation to operative intervention was significantly shorter for complicated appendicitis (3.8 vs 4.7 hours for acute appendicitis). The high rate of complicated appendicitis with its subsequent sequelae of increased morbidity and resource expenditure is primarily the direct result of patient delay in seeking medical attention and not the result of diagnostic dilemma or surgical delay. Public education, specifically targeting those groups at risk, may provide a substantial and significant solution to the complicated appendix.

Blunt splenic injuries: dedicated trauma surgeons can achieve a high rate of nonoperative success in patients of all ages.

BACKGROUND: Selective nonoperative management (NOM) of blunt splenic injuries is becoming a more prevalent practice. Inclusion criteria for NOM, which have been a source of controversy, continue to evolve. Age > or = 55 years has been proposed as a predictor for failure of and even a contraindication to NOM of blunt splenic trauma. Additionally, the high rate of NOM in children (up to 79%) has been attributed to their management by pediatric surgeons. We evaluated our experience with NOM of blunt splenic injury with special attention to these age groups. METHODS: By using our trauma registry, all patients with blunt splenic injuries (documented by computed tomography, operative findings, or both) cared for over a 36-month period, at a single American College of Surgeons verified Level I trauma center were reviewed. Detailed chart reviews were performed to examine admission demographics, laboratory data, radiologic findings, outcome measures, and patient management strategy. All patients were managed by nonpediatric trauma surgeons. We then compared our adult data with that in the recent literature and our pediatric data with that of the National Pediatric Trauma Registry over the same time period. RESULTS: We identified 251 consecutive patients with blunt splenic injuries. Eighteen patients who expired in the immediate postinjury period were excluded from statistical evaluation. No deaths occurred as a result of splenic injury. Of the remaining 233 patients, 73 patients (31%) required early celiotomy, 160 patients (69%) were selected for NOM, with 151 patients (94%) being successfully managed without operation. Blunt splenic injury occurred in 23 patients age 55 years or older. Eighteen patients (78%) were selected for NOM and 17 patients (94%) were successfully treated without operation. Blunt splenic injury occurred in 35 patients less than 16 years of age. Thirty-two patients (91%) were selected for NOM. Thirty-one patients (89% of all pediatric patients) were successfully treated without operation. CONCLUSION: Age > or = 55 years is not a contraindication to nonoperative management of blunt splenic injuries. Children with blunt splenic injuries can be successfully managed nonoperatively by nonpediatric trauma surgeons.

A novel putative low-affinity insulin-like growth factor-binding protein, LIBC (lost in inflammatory breast cancer), and RhoC GTPase correlate with the inflammatory breast cancer phenotype.

Inflammatory breast cancer is a rapidly growing, distinct form of locally advanced breast cancer that carries a guarded prognosis. To identify the genes that contribute to this aggressive phenotype, we compared under- and overexpressed sequences in an inflammatory breast tumor cell line with those of actively replicating normal human mammary epithelial cell lines using differential display. Of the 17 transcripts isolated and characterized from these experiments, overexpression of RhoC GTPase and loss of expression of a novel gene on 6q22, LIBC (lost in inflammatory breast cancer), were highly correlated (P<0.0095 and P<0.0013, respectively) with the inflammatory phenotype when a panel of archival inflammatory breast cancers was compared with noninflammatory stage III breast cancers by in situ hybridization. This study suggests two new molecular markers specific for inflammatory breast cancer.

Subchronic inhalation studies of complex fragrance mixtures in rats and hamsters.

Users of consumer products are invariably and intentionally exposed to complex mixtures in such products. With finished fragrance products, these mixtures may represent 100 or more fragrance raw materials (FRMs). The objective of the described studies was to evaluate the safety of finished fragrance products via the inhalation route. In total, the finished products contained approximately 100 FRMs at concentrations of 1% or greater. Major FRMs evaluated included benzyl acetate, coumarin, hydroxycitronellal, musk ketone, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-gamma-2-be nzopyran (HHCB) and phenyl ethyl alcohol. Groups of rats or hamsters were exposed by inhalation (whole body) to the mixtures at 5, 9 or 50 mg/m3 for 4 h per day, 5 days per week for 6 or 13 weeks. For each of the fragrance products, the doses used generally represented a ten- to 100-fold exaggeration of levels expected to be achieved during typical use by consumers. With one exception, the fragrances were aerosolized prior to introduction into the inhalation chamber. The exception product was formulated with a propellant, packaged in a pressurized container and expelled with an automated actuator. In all studies, chamber concentrations of fragrance were monitored. Particle sizes ranged from 0.5 to 7.5 microm, depending on the study. Subchronic exposure to all fragrance mixtures resulted in no toxicologically significant effects on animal survival, behavior, body weights or weight gains, organ weights, or in hematology, clinical chemistry, or urinalysis parameters. No gross pathological or histopathological findings related to test material exposures were observed. These studies support the conclusions that the fragrance mixtures would not pose a hazard to product users based on repeated and exaggerated inhalation exposures of animals.

Contig map of the Parkinson's disease region on 4q21-q23.

We have constructed a yeast artificial chromosome contig (YAC) map of human chromosome 4q21-q23 across the Parkinson's disease region by combining molecular and fluorescence in situ hybridization techniques. This map contains 55 YACs and 51 molecular markers, including 23 polymorphic markers. We have also isolated one P1 and 33 bacterial artificial chromosomes located within this contig. Plasmid libraries were generated from 11 of these BAC and P1 clones, and 614 random plasmid clones were sequenced for a total of about 200 kb. This contig allowed us to precisely determine the location of 18 transcripts within the D4S2460-D4S2986 interval, including the alpha-synuclein gene found to be mutated in some families with Parkinson's disease.

A stingray spine in the scapula of a bottlenose dolphin.

A stingray spine was found lodged in the scapula of a deceased 272 cm, male bottlenose dolphin (Tursiops truncatus) from South Carolina (USA) following skeletal preparation, nearly 6 mo after necropsy. No external puncture wound, internal bruising, or laceration of muscle tissue surrounding the scapula was evident during necropsy of the animal. Implantation of the spine did not appear to be related to the death of the dolphin, but probably occurred at an early age. Abnormal development of bone surrounding the spine resulted in the formation of a cavity at the wound site. Two mechanisms were considered as contributors for the cavity formation. These were the mechanical action of the spine stimulating the body's defense system for managing foreign objects, and the release of potent toxins from the spine sheath.

Mutation in the alpha-synuclein gene identified in families with Parkinson's disease.

Parkinson's disease (PD) is a common neurodegenerative disorder with a lifetime incidence of approximately 2 percent. A pattern of familial aggregation has been documented for the disorder, and it was recently reported that a PD susceptibility gene in a large Italian kindred is located on the long arm of human chromosome 4. A mutation was identified in the alpha-synuclein gene, which codes for a presynaptic protein thought to be involved in neuronal plasticity, in the Italian kindred and in three unrelated families of Greek origin with autosomal dominant inheritance for the PD phenotype. This finding of a specific molecular alteration associated with PD will facilitate the detailed understanding of the pathophysiology of the disorder.

Percutaneous penetration of N-nitrosodiethanolamine through human skin (in vitro): comparison of finite and infinite dose applications from cosmetic vehicles.

N-Nitroso compounds (nitrosamines) have been detected at the parts per billion level in a wide variety of matrices including industrial chemicals, pharmaceuticals, and food. Although N-nitrosodiethanolamine (NDELA) may be detected as an impurity in some cosmetic products, studies on NDELA absorption through human skin have been limited. A study to determine the extent of NDELA absorption following topical application was therefore undertaken to assist in the proper assessment of risk following unintended exposure. NDELA absorption was measured in vitro through human cadaver skin using isopropyl myristate (IPM) and generic prototype personal-care formulations (sunscreen and shampoo) spiked with [14C]NDELA. When applied as a finite dose at a concentration of 0.06% or lower, NDELA absorption was found to be a linear function of concentration. Total absorption at 48 hr ranged from approximately 35 to 65% of the dose and was formulation dependent (IPM > shampoo > or = sunscreen). Absorption occurred relatively rapidly from all formulations and peak rates of absorption were seen within the first 5 hr from the IPM and shampoo formulations. When applied as an infinite dose, total NDELA absorption followed a different rank order (shampoo > or = IPM > sunscreen) and evidence of barrier damage was seen with the shampoo formulation.

Is exploratory celiotomy necessary for all patients with truncal stab wounds?

Mandatory exploratory celiotomy was carried out in 1241 consecutive patients with truncal stab wounds. Four hundred seventy-one (38%) patients who had no intra-abdominal injury identified at operation developed 16 complications (3%), with one patient (0.2%) dying postoperatively. The average length of hospitalization (5 days) was increased if the patient: (1) required a simultaneous operation for associated site injuries (9 days), (2) developed postoperative complications (16 days), or (3) required reoperation (27 days). The 1990 projected cost per patient for routine celiotomy has increased 92% over that seen 10 years ago. Selective management protocols using observation, repeated physical examination, and special diagnostic procedures could be instituted for asymptomatic hemodynamically stable patients with truncal stab wounds if appropriate facilities and personnel are available. Successful implementation should preserve medical resources for those patients with trauma requiring a life-saving operation.

Angioplasty and stenting of completely occluded iliac arteries.

Percutaneous angioplasty and placement of balloon-expandable intraluminal stents were performed in 12 iliac occlusions in 12 patients. Indications were limb salvage in seven and claudication in five. After successful stenting, ankle-brachial indexes improved by 0.15 or more in 11 of 12 patients (mean increase, 0.40), transstenotic pressure gradients decreased to less than 5 mm Hg (mean, 0.58 mm Hg) in all patients, and improvement in clinical grade was seen in all patients. At follow-up at 1-14 months (median, 6 months), ankle-brachial indexes were stable (mean, 0.95), and clinical grades were unchanged in all patients. Complications occurred in two patients; both experienced distal embolization, and one, who was receiving corticosteroid therapy, also suffered stent thrombosis. Local surgical embolectomy was successful in both patients, and the thrombosed stent was recanalized with urokinase. This early experience suggests that stenting may play an important role in the management of iliac occlusions, especially in poor surgical candidates.