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W Shoemaker

Publications and source records attributed to W Shoemaker.

17 recordsLinked to original sources
PubMed1998

TRISS methodology in trauma: the need for alternatives.

BACKGROUND: Trauma and Injury Severity Score (TRISS) methodology has become a standard tool for evaluating the performance of trauma centres and identifying cases for critical review. Recent work has identified several limitations and questioned the validity of the methodology in certain types of trauma. METHODS: The usefulness and limitations of the TRISS methodology were evaluated in an urban trauma centre. Trauma registry data of 5445 patients with major trauma were analysed with respect to 30 demographic, prehospital, injury severity and hospitalization attributes. The performance of TRISS was measured primarily by the percentage of misclassifications, including false positives and false negatives, comparing the survival status predicted by TRISS with the true status. Sensitivity, specificity, and positive and negative predictive values were also measured for subgroups defined by the 30 attributes. Logistic regression analysis was used to identify significant independent factors related to the performance of TRISS. RESULTS: The overall misclassification rate was 4.3 per cent. However, in many subgroups of patients with severe trauma the misclassification rate was very high: 34 per cent in patients older than 54 years with Injury Severity Score (ISS) greater than 20; 29 per cent in those with fall injuries and ISS above 20; 29 per cent in patients with injuries involving four or more body areas and ISS greater than 20; 28.6 per cent in patients with injuries needing admission to the intensive care unit (ICU) and ISS greater than 20; 26.4 per cent in patients in severe distress before reaching hospital with ISS greater than 20; and 26.1 per cent in patients whose ISS score was above 20 and who had complications in hospital. CONCLUSION: The TRISS methodology has major limitations in many subgroups of patients, especially in severe trauma. In its present form TRISS has no useful role in major urban trauma centres. Its use should be seriously reconsidered, if not abandoned.

Aged↗
PubMed1998

One hundred five penetrating cardiac injuries: a 2-year prospective evaluation.

OBJECTIVES: To analyze the parameters measured in the field, during transport, and upon arrival of the physiologic condition of patients sustaining penetrating cardiac injuries, along with the Cardiovascular Respiratory Score (CVRS) component of the Trauma Score, the mechanism and anatomical site of injury, operative characteristics, and cardiac rhythm as predictors of outcome. We also set out to identify a set of patient characteristics that best predict mortality outcome and to correlate cardiac injury grade as determined by the American Association for the Surgery of Trauma-Organ Injury Scale (AAST-OIS) with mortality. METHODS: This report was a prospective study at American College of Surgeons Level I urban trauma center. Interventions included thoracotomy, sternotomy, or both, for resuscitation and definitive repair of cardiac injury. The main outcome measures used were those parameters measuring physiologic condition of patients, CVRS, mechanism and anatomical site of injury, mortality, and grade of injury. RESULTS: A total of 105 patients sustained penetrating cardiac injuries: 68 injuries (65%) were gunshot wounds and 37 injuries (35%) were stab wounds. The mean Injury Severity Score was 36. Of the 105 wounds, 23 wounds (22%) involved multiple-chamber injuries. The overall survival was 35 of 105 patients (33%): survival of gunshot wound victims was 11 of 68 patients (16%); survival of stab wound victims was 24 of 37 patients (65%). Emergency department thoracotomy was performed in 71 of the 105 patients (68%) with 10 survivors (14%). CVRS: 94% mortality (50 of 53) when CVRS = 0, 89% mortality (57 of 64) when CVRS = 0 to 3, and 31% mortality (12 of 39) when CVRS 4 to 11 (p < 0.001). The presence of sinus rhythm when pericardium was opened predicted survival (p < 0.001). Anatomical site of injury (injured chamber) and the presence of tamponade did not predict survival. Stepwise logistic regression analysis identified gunshot wound, exsanguination, and restoration of blood pressure as most predictive variables of mortality. AAST-OIS injury grade and mortality: grade I, 0 of 1 (0%); grade II, 1 of 2 (50%); grade III, 2 of 3 (66%); grade IV, 28 of 50 (56%); grade V, 29 of 38 (76%); grade VI, 10 of 11 (91%). Overall incidence: grades IV-VI, 99 of 105 (94%). CONCLUSIONS: Parameters measuring physiologic condition, CVRS, and mechanism of injury are significant predictors of outcome in penetrating cardiac injuries. AAST-OIS injury grades I-III are rare in penetrating cardiac trauma. AAST-OIS Injury grades IV-VI are common in penetrating cardiac trauma and accurately predict outcome.

Blood Pressure↗
PubMed1997

A unified approach to the surgical exposure of pancreatic and duodenal injuries.

One of the greatest challenges to any surgeon is the intraoperative detection and surgical management of duodenal and pancreatic injuries. A uniform approach to the surgical exposure of all suspected pancreatic and duodenal injuries will decrease their morbidity and mortality by identifying all injuries. Proper intraoperative assessment and grading will help with procedure selection from the broad surgical armamentarium available to manage these injuries.

Duodenum↗
PubMed1997

Penetrating esophageal injuries: time interval of safety for preoperative evaluation--how long is safe?

OBJECTIVES: This study was performed to assess the experience with penetrating esophageal injuries of an urban Level I trauma center and to attempt to correlate the time to establish a diagnosis with outcome including death, surgical intensive care unit length of stay, and esophageal-related complications. METHODS: Retrospective study over a 72-month period at a single institution comparing age, admission blood pressure, Revised Trauma Score (RTS), Injury Severity Score (ISS), mechanism and anatomic location of injury, and time interval from admission to the operating room (OR) between nonsurvivors and survivors. Patients who survived to reach the operating room were divided into two groups: those who went immediately to the operating room (no preoperative evaluation) and those who underwent diagnostic studies to identify their injuries (preoperative evaluation). Data analysis was done of the same parameters plus average number of associated injuries, complications, and intensive care unit length of stay. Statistical methods used univariate analysis (Fisher's exact test and Student's t test). RESULTS: Forty-three patients were identified with penetrating esophageal injuries and had the following characteristics: 36 males (84%) and 7 females (16%); mean RTS, 9.39; mean ISS, 28.1; mean time interval to OR, 9.8 hours. Associated injuries occurred with 42 patients (98%). The overall complication rate was 14 of 32 (44%), and the overall mortality was 11 of 43 (26%). Corrected mortality was 22%. Differences were noted between nonsurvivors and survivors in the following parameters: admission blood pressure < 90, 11 of 11 versus 3 of 29 (p < 0.001); RTS, 2.364 versus 11.406 (p < 0.001); ISS, 45 versus 21 (p < 0.001); time interval from admission to OR, 18.3 minutes versus 9.8 hours (p < 0.05). Thirty-six patients survived to reach the operating room, 18 in the no preoperative evaluation group and 17 in the preoperative evaluation group. No statistically significant differences were noted between these two groups in the following parameters: age, RTS, ISS, admission blood pressure, anatomic location of injury, number of associated injuries, or intensive care unit length of stay. Average length of time to the operating room was 16.7 hours in the preoperative evaluation group and 1.4 hours in the no preoperative evaluation group (p < 0.001). Twelve complications (all esophageal-related) occurred among seven patients in the preoperative evaluation group, and seven complications (five esophageal-related) occurred among seven patients in the no preoperative evaluation group. Because of the small sample size, this failed to reach a statistical difference (p < 0.05). CONCLUSIONS: Esophageal injuries carry a high morbidity and mortality. Although no definite conclusion can be drawn because of the small sample size, there does appear to be an increased morbidity associated with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, the rapid diagnosis and definitive repair of esophageal injury should be made a high priority.

Adult↗
PubMed1995

Biochemical actions of chronic ethanol exposure in the mesolimbic dopamine system.

In previous studies, we have demonstrated that chronic administration of morphine or cocaine produces some common biochemical adaptations in the ventral tegmental area (VTA) and nucleus accumbens (NAc), components of the mesolimbic dopamine system implicated in the reinforcing actions of these and other drugs of abuse. Since this neural pathway is also implicated in the reinforcing actions of ethanol, it was of interest to determine whether chronic ethanol exposure results in similar biochemical adaptations. Indeed, as seen for chronic morphine and cocaine treatments, we show here that chronic ethanol treatment increased levels of tyrosine hydroxylase and glial fibrillary acidic protein immunoreactivity, and decreases levels of neurofilament protein immunoreactivity, in the VTA. Also like morphine and cocaine, ethanol increases levels of cyclic AMP-dependent protein kinase activity in the NAc. These actions of ethanol required long-term exposure to the drug, and were in most cases not seen in the substantia nigra or caudateputamen, components of the nigrostriatal dopamine system studied for comparison. Altered levels of tyrosine hydroxylase in catecholaminergic cells frequently reflect altered states of activation of the cells. Moreover, increasing evidence indicates that ethanol produces many of its acute effects on the brain by regulating NMDA glutamate and GABAA receptors. We therefore examined the influence of chronic ethanol treatment on levels of expression of specific glutamate and GABA receptor subunits in the VTA. It was found that long-term, but not short-term, ethanol exposure increased levels of immunoreactivity of the NMDAR1 subunit, an obligatory component of NMDA glutamate receptors, and of the GluR1 subunit, a component of many AMPA glutamate receptors; but at the same time, long-term ethanol exposure decreased immunoreactivity levels of the alpha 1 subunit of the GABAA receptor complex. These changes are consistent with an increased state of activation of VTA neurons inferred from the observed increase in tyrosine hydroxylase (TH) expression. These results demonstrate that chronic ethanol exposure results in several biochemical adaptations in the mesolimbic dopamine system, which may underlie prominent changes in the structural and functional properties of this neural pathway related to alcohol abuse and alcoholism.

Adenylyl Cyclases↗
PubMed1995

Gunshot wounds seen at a county hospital before and after a riot and gang truce: Part Two.

An analysis was undertaken of the number of gunshot wound victims seen at a Los Angeles County hospital both before and after the Los Angeles riot. Since the LA riot the gang truce between the "Bloods" and the "Crips" resulted in a significant decrease in the number of gunshot wound victims seen at a level I trauma center in Los Angeles. Unfortunately, this lasted for only three months. The resurgence of shootings, mainly of the drive-by type (82%), to an occurrence rate higher than ever before, has negated any positive effect of the gang truce and indicates the need for additional measures to control gang violence.

Adolescent↗
PubMed1994

Asymptomatic stab wounds of the chest.

In a prospective study of 4,106 consecutive cases of initially asymptomatic stab wounds of the chest, 88% were successfully treated as outpatients after negative findings on a repeat chest x-ray film 6 hours after presentation, 12% of patients required tube thoracostomy for delayed pneumothoraces of hemothoraces, 0.2% required thoracotomy for delayed and continued bleeding or cardiac injuries, 1% of patients with small pneumothoraces (subjectively less than 20%) were observed, and 68% patients remained asymptomatic. The accuracy of the initial chest x-ray film was 95% overall, with a specificity of 99.9%. The negative predictive value of only 87.4% precludes the immediate outpatient management of these asymptomatic patients. The overall mortality was 0.1%, mortality during or following surgery was 50%. Of the four patients with initially unsuspected cardiac injuries, two patients died in the operating room. Asymptomatic patients (with normal findings on chest x-ray films) may be discharged after 8 hours of observation. Asymptomatic patients with nonprogressive small pneumothoraces (less than 20%) not requiring a chest tube may be discharged after 48 hours of observation. Thirty-two percent of those observed for initially small pneumothoraces on chest x-ray films, had progression of their injuries and required tube thoracostomy. All patients should have close outpatient follow-up.

Adult↗
PubMed1994

Spent bullets and their injuries: the result of firing weapons into the sky.

People often celebrate holidays by firing guns into the air without realizing that this can cause serious injury or death. The present study identified 118 patients treated since 1985 who were hit with spent bullets. Most (77%) were hit in the head. The mortality rate was 32%, which is significantly higher than for all gunshot wound victims in general seen at the same medical center. Laws have been enacted to help prevent people shooting into the sky, but more education and enforcement are required to prevent these serious and preventable injuries.

Adolescent↗
PubMed1994

Extremity gunshot wounds: Part one--Identification and treatment of patients at high risk of vascular injury.

Cost containment is important in this time of inner-city economic and health-care crisis. This paper examines patients who were treated for gunshot wounds (GSWs) of the extremities. During the study period 1978 through 1992, 16,316 patients (18,349 extremities) were treated for extremity GSWs. Nine patients with asymptomatic injuries in proximity to vascular structures who were treated before the use of duplex Doppler ultrasonography (DDU) were later found to have surgically treatable vascular injuries. These were identified and treated on an outpatient basis with no long-term morbidity or mortality. With the advent of DDU, asymptomatic vascular injuries were no longer missed. A conservative estimate of the cost savings from this study is more than $47,000,000.00. The use of DDU and the enclosed protocols for treating asymptomatic extremity wounds prevented 16,450 needless angiograms, with an additional savings of $32,900,000.00, for a total savings of more than $79,900,000.00. With a more liberal use of DDU and angiography to eliminate the rare missed vascular injuries (0.09%), and the use of protocols to analyze patients with asymptomatic injuries, many extremity GSW victims (79% in this study) can be safely treated as outpatients, eliminating the need for expensive in-hospital observation.

Algorithms↗
PubMed1994

Civilian gunshot wounds--outpatient management.

Cost containment is important in this time of inner-city economic and health-care crisis. Of 28,150 patients treated for gunshot wounds (GSWs) from 1977 through 1991, 16,892 (60%) were treated as outpatients after emergency department evaluation and treatment. The complication rate was 1.8% (mostly infections), and nine patients were later found to have vascular injuries requiring surgical treatment. These were identified later at outpatient follow-up and treated with no long-term morbidity or mortality. A conservative estimate of the cost savings from this study was more than $37 million. With a more liberal use of angiography to eliminate rare missed vascular injuries, many GSW victims can be safely treated as outpatients, eliminating the need for expensive in-hospital observation.

Adult↗
PubMed1992

Prospective trial of supranormal values as goals of resuscitation in severe trauma.

We prospectively tested the effect of the early postinjury attainment of supranormal values of cardiac index (> or = 4.52 L/min per square meter), oxygen delivery (> or = 670 mL/min per square meter), and oxygen consumption (> or = 166 mL/min per square meter) on outcome in traumatized patients with an estimated blood loss of 2000 mL or more. The goals in control patients were to attain normal values for all hemodynamic measurements. During the 6-month period, 33 protocol patients and 34 control patients with similar vital signs, estimated blood losses, and severity of injuries were enrolled in the study. Eight (24%) protocol patients died, while 15 (44%) control patients died. The protocol patients had fewer mean (+/- SEM) organ failures per patient (0.76 +/- 1.21 vs 1.59 +/- 1.60), shorter stays in the intensive care unit (5 +/- 3 vs 12 +/- 12), and fewer mean days requiring ventilation (4 +/- 3 vs 11 +/- 10) than did the control patients (P < .05 for each). We conclude that attaining supranormal circulatory values improves survival and decreases morbidity in the severely traumatized patient.

Adolescent↗
PubMed1991

Opioid-dependent behaviors in infant rats: effects of prenatal exposure to ethanol.

Pregnant rats were given diets containing either 5% ethanol, an isocaloric (pair-fed) diet, or casein pellets. Offspring were tested at postnatal day 10 for isolation-induced ultrasonic vocalizations and subsequent stress-induced analgesia. Rats prenatally exposed to ethanol vocalized significantly less in the five minutes during isolation. The opiate, morphine, caused a greater suppression of vocalizations in alcohol-exposed pups compared to controls, while the increased calling normally seen with the opiate antagonist, naltrexone, was attenuated. In a test in which the pup withdraws a paw from a hot plate (48 degrees C), prenatal alcohol offspring demonstrated baseline latencies (no isolation) similar to controls but had greatly attenuated responses in their isolation-induced analgesia. Since both vocalization and analgesia responses have been determined to be modulated by the endogenous opioid system, the aberrant responses of the prenatal-ethanol-exposed offspring can be interpreted as failures to respond by opioid release/secretion to appropriate stimuli.

Aging↗
PubMed1984

The eye as a peripheral sensor.

The eye is no longer an organ onto itself, but is now being used as a sensor for the rest of the body. The development, clinical uses, and future applications of conjunctival capillary monitoring are presented.

Adult↗
PubMed1982

Noninvasive evaluation of peripheral vascular disease using transcutaneous oxygen tension.

Transcutaneous oxygen tension (PtcO2) was used for noninvasive determination of blood supply in 25 patients evaluated for peripheral arterial disease. PtcO2 values were compared with segmental Doppler pressure, pulse volume recording, pulse reappearance time, and angiography in patients being evaluated for wound healing problems, amputations, and peripheral bypass procedures. PtcO2 was measured using a heated (45 degrees C) Clark polarographic electrode to quantitate the oxygen which diffuses from the dermal capillaries to the skin surface. Control PtcO2 values recorded over the chest or shoulder taken while patients were breathing room air were 78 +/- 8 mm Hg. PtcO2 values greater than 50 mm Hg predicted success for levels of amputation and for wound healing without reconstructive procedures; values of 40 mm Hg or less were associated with continued wound problems and complication after amputation. Increased PtcO2 values after vascular reconstruction of the legs predicted improved clinical status on follow-up examinations up to 6 months. PtcO2 predicted the extent of vascular disease as well as the other noninvasive tests and angiography. We conclude that (1) PtcO2 tension is a simple, accurate, noninvasive method to determine the appropriate level of amputation, wound healing potential, and effectiveness of bypass procedures, and (2) PtcO2 values correlate well with angiography and noninvasive evaluations.

Aged↗