Findings and outcomes of psychological evaluations of gastric bypass applicants.

BACKGROUND: Among severely obese persons seeking surgical treatment, lifetime prevalence rates of Axis 1 psychiatric disorders range up to 50%; 27% to 42% have a diagnosable psychiatric disorder at the time of evaluation. Despite recommendations by the National Institutes of Health Consensus Development Panel that evaluation for surgery include a mental health component, little data are available on the outcomes of such evaluations. Similarly, there are also few data on the frequency and type of psychotropic medication use by these patients. The primary objective of this study was to describe the recommendations resulting from psychological evaluations of bariatric surgery applicants; a secondary purpose was to describe the point and lifetime prevalences of psychotropic medication use. METHODS: We examined the psychological evaluation recommendations of successive gastric bypass applicants at the Medical University of South Carolina. RESULTS: Results indicated that the overwhelming majority (81.5%) of gastric bypass applicants had no psychological contraindication to surgery. A smaller percentage (15.8%) required psychological treatment before surgery, and only 2.7% of all applicants were considered psychologically inappropriate for surgery. Results also indicate that 47.7% were using at least 1 psychotropic medication at the time of the evaluation, and that 9.2% were using more than 1. The overwhelming majority of medications used were antidepressants, followed by antianxiety medications and mood stabilizers. CONCLUSIONS: These results indicate that the vast majority of patients will not be denied surgery as the result of a psychological assessment, yet approximately 20% of patients may be considered, based on psychological evaluation, psychologically inappropriate for immediate surgery, at least without initial treatment. These data also suggest that pharmacologic treatment of psychiatric disorders is quite common among gastric bypass applicants.

Complications of surgery for obesity.

Morbidly obese patients are already considered high-risk because of their comorbidities. Surgical procedures for obesity are, for the most part, completely elective. Careful counseling of the patient before and after the surgery is extremely important. This article reviews the general complications of bariatric surgery and specific complications of restrictive procedures.

ApoE knockout mice expressing human matrix metalloproteinase-1 in macrophages have less advanced atherosclerosis.

Matrix metalloproteinase-1 (MMP-1), or interstitial collagenase, has been hypothesized to contribute to the progression of the human atherosclerotic lesions by digesting the fibrillar collagens of the neointimal ECM. The apolipoprotein E knockout (apoE0) mouse model develops complex atherosclerotic lesions, but mice do not possess a homologue for MMP-1. To provide an in vivo evaluation of the role of MMP-1 in atherogenesis, we created a transgenic mouse model that expresses this enzyme specifically in the macrophage, under the control of the scavenger receptor A (SCAV) enhancer/promoter. The MMP-1 transgenic mice were crossed into the apoE0 background and fed an atherogenic diet for 16-25 weeks. Surprisingly, the transgenic mice demonstrated decreased lesion size compared with control littermates. The lesions of the transgenic animals were less extensive and immature, with fewer cellular layers and a diminished content of fibrillar collagen. There was no evidence of plaque rupture. Our data suggest that remodeling of the neointimal extracellular matrix by MMP-1 is beneficial in the progression of lesions.

Continuous infusions of lorazepam, midazolam, and propofol for sedation of the critically ill surgery trauma patient: a prospective, randomized comparison.

OBJECTIVE: To compare the efficacy, safety, and cost of continuous infusions of lorazepam, midazolam, and propofol in a critically ill trauma/surgery patient population. DESIGN: A prospective, randomized, nonblinded, single center. SETTING: A 16-bed intensive care unit. PATIENTS: A total of 30 ventilated patients who were 18-70 yrs of age and required pharmacologic sedation. Patients with renal and/or liver failure, a history of alcohol abuse, a head injury, or in a coma were excluded. INTERVENTIONS: Patients were randomized by block design to receive lorazepam, midazolam, or propofol. Initial boluses and infusion rates were as follows: lorazepam 0.05 mg/kg, then 0.007 mg/kg/hr; midazolam 0.05 mg/kg, then 0.003 mg/kg/hr; and propofol 0.25 mg/kg, then 0.06 mg/kg/hr. Sedation was assessed and agents titrated every 5-10 mins to achieve > or =2 and <5 on the modified Ramsay scale. Once adequate response was achieved, agents were titrated to maintain the desired level of sedation. MEASUREMENTS AND MAIN RESULTS: Maintenance doses of lorazepam 0.02+/-0.01 mg/kg/hr, midazolam 0.04+/-0.03 mg/kg/hr, and propofol 2.0+/-1.5 mg/kg/hr achieved the desired level of sedation 68%, 79%, and 62% of the time, respectively. Oversedation occurred most often with lorazepam, compared with midazolam and propofol, at 14%, 6%, and 7% of the assessment times, respectively. Undersedation occurred most frequently with propofol compared with lorazepam and midazolam, at 31%, 18%, and 16% of the assessment times, respectively. The mean number of dosage changes per day was 7.8+/-4.3 for lorazepam, 4.4+/-2.9 for midazolam, and 5.6+/-6.0 for propofol (p = .91). Sedation costs per patient day (mean +/- SD) were $48+/-$76 (lorazepam), $182+/-$98 (midazolam), and $273+/-$200 (propofol) (p = .005). The potential savings, if all study patients had received lorazepam, is $14,208 compared with $8,808 if all received midazolam. CONCLUSIONS: The data suggest that lorazepam appears to be a cost-effective choice for sedation; however, oversedation may be problematic. Midazolam is the most titratable drug in our population, avoiding excessive oversedation or undersedation. Trauma patients may respond inadequately to propofol even at higher doses. Lorazepam may be the sedative of choice in critically ill trauma/surgery patients.

A pilot study evaluating the efficacy of a fully acetylated poly-N-acetyl glucosamine membrane formulation as a topical hemostatic agent.

BACKGROUND: Topical hemostatic agents are frequently needed for control of intraoperative bleeding. Currently available topical products each have potential drawbacks, making a more effective topical hemostatic agent desirable. This study was performed to evaluate the effectiveness of a particular formulation of a newly available polysaccharide polymer, poly-N-acetyl glucosamine (p-GlcNAc), as a topical hemostatic agent for use in the operating room. Swine splenic incision and splenic capsular stripping hemorrhage models were initially used, with a subsequent pilot human study then performed. METHODS: For the swine splenic incision model, anesthetized immature female Yorkshire white swine had a 3 x 8 mm incision created on the spleen. One of 3 agents (p-GlcNAc membrane, oxidized cellulose, or absorbable collagen) was sequentially applied to individual wounds and digitally compressed for 20 seconds. The wound was observed without pressure for 2 minutes. Up to 8 wounds per animal were created in 7 animals. For the swine splenic capsular stripping model a 2 x 2 cm area of capsular stripping on the surface of the spleen to a depth of 3 mm was created. Either p-GlcNAc membrane or oxidized cellulose was applied and digitally compressed for 60 seconds, followed by observation without pressure for 2 minutes. Six wounds per animal were created in 2 animals. If bleeding persisted in either model, a new cycle of compression was applied. These steps were repeated until hemostasis was achieved. No change in hemodynamics or coagulation factors was observed in either model. Subsequently, 10 consecutive patients undergoing elective small-bowel surgery were enrolled on pilot study. A 5 x 3 x 3 mm cruciate incision was created midway between the mesenteric and antimesenteric borders of the small bowel. Either p-GlcNAc membrane formulation or oxidized cellulose was applied (the sequence alternated per patient) with a 400-mg weight used for even, direct pressure. A second cruciate incision was then created on the contralateral side of the bowel to evaluate the second material. The number of applications required for hemostasis was assessed. Hemodynamics, small-bowel pathologic condition, and hematologic parameters were evaluated. RESULTS: The p-GlcNAc membrane required fewer cycles of compression in the swine splenic incision model to achieve hemostasis than either absorbable collagen or oxidized cellulose (1.25 vs 2.58 and 3.41, respectively; P < .01) and caused more effective immediate cessation of bleeding (79% for p-GlcNAc vs 17% for both absorbable collagen and oxidized cellulose). With the more traumatic splenic capsular stripping model, p-GlcNAc required fewer cycles of compression to achieve hemostasis than oxidized cellulose (average, 2.5 versus 6.8 respectively; P < .01) and was able to achieve hemostasis with greater efficacy (50%) in 2 applications than did oxidized cellulose (0%; P < .01). When used in the human pilot study, p-GlcNAc membranes required fewer cycles of compression than oxidized cellulose (2.5 vs 5.4, respectively; P < .002), was able to stop bleeding with greater efficacy in 1 cycle of compression (50% vs 0%, respectively; P < .01), and ultimately accomplished hemostasis in 80% of the cases as opposed to 20%. CONCLUSIONS: On the basis of its greater hemostatic efficacy as compared with collagen or oxidized cellulose-based products, p-GlcNAc holds promise as an effective topical hemostatic agent and deserves further evaluation.

Magnetic resonance imaging differentiates between necrotizing and non-necrotizing fasciitis of the lower extremity.

BACKGROUND: Distinction between uncomplicated infective fasciitis and early necrotizing fasciitis can be extremely difficult without operation, yet the management and prognosis of both conditions depend greatly on early recognition and assessment of the extent of involvement. STUDY DESIGN: This was a prospective review of the utility of magnetic resonance imaging (MRI) in nine patients with suspected infective or necrotizing fasciitis treated at an academic medical center or a Veterans Administration hospital. RESULTS: Magnetic resonance imaging documented fascial inflammation, characterized by low intensity on T1-weighted images and high intensity on T2-weighted images, in all nine patients. Absence of gadolinium contrast enhancement on T1-weighted images reliably detected fascial necrosis in all six patients who required operative debridement. Magnetic resonance imaging was extremely useful in defining the extent of fasciitis and was more accurate in predicting necrosis or pyomyositis than was myoglobinuria or elevation of serum creatine kinase or lactate dehydrogenase. Operation was avoided in two patients without evidence of necrosis on MRI. One patient without evidence of necrosis, explored because of contradictory clinical findings, was confirmed at operation to have cellulitis without necrosis. CONCLUSIONS: Magnetic resonance imaging with gadolinium contrast accurately determines the presence of necrosis and the need for operation in patients with fasciitis of the lower extremity. Preoperative determination of the extent of involvement facilitates operative planning.

Abdominal compartment syndrome.

PURPOSE: Two cases of abdominal compartment syndrome are described and the pathophysiology associated with it is reviewed. CLINICAL FEATURES: The first patient was a 46-yr-old man who sustained extensive blunt abdominal injuries following a fall. The second was a 54-yr-old man involved in a motor vehicle accident with blunt abdominal trauma. In both cases, the patients developed an extremely tense abdomen, increasing peak inspiratory pressures, hypercarbia and oliguria. Both demonstrated improvement in cardiac performance and ventilatory variables following an emergency decompressive celiotomy. CONCLUSION: Abdominal compartment syndrome results in impairment of organ function secondary to increased intraabdominal pressure. These patients require emergency decompressive celiotomy to relieve the symptoms. However, the incidence of intractable asystole and hypotension during this procedure is high and vigilance must be maintained during the release of the increased intraabdominal pressure.

Trans-jugular extraction of bullet embolus to the heart.

Bullet emboli to the heart are rare and are typically treated by operative extraction through a median sternotomy and cardiotomy. This report details the case of an 18-year-old male who sustained two gunshot wounds, one of which lodged in his left renal vein. At laparotomy, the bullet embolized to the right atrium via the inferior vena cava. Under fluoroscopic guidance the bullet was retrieved with a snare introduced percutaneously through the right internal jugular vein. Sternotomy and possible cardiopulmonary bypass were avoided.

Application of American College of Surgeons' field triage guidelines by pre-hospital personnel.

BACKGROUND: The American College of Surgeons' Committee on Trauma (ACSCOT) has developed field triage guidelines intended to identify seriously injured patients. Unlike the 1990 version, the 1993 revision calls for on-line medical control assistance with the triage decision for patients whose only marker of severe injury is the mechanism of their injury. We prospectively examined the application of the 1990 ACSCOT field triage guidelines to evaluate Emergency Medical Service (EMS) utilization of these guidelines and the potential effects of the 1993 revision. STUDY DESIGN: Emergency Medical Service personnel identified all ACSCOT criteria applicable to patients delivered to the level 1 trauma center at the Medical University of South Carolina. Trauma registry data were used to compare actual injury severity with applicable indicators. Patients with an injury severity score greater than or equal to 16 were considered seriously injured. The South Carolina state trauma and EMS databases were queried to estimate systemwide overtriage and undertriage rates. RESULTS: Questionnaires were completed for 753 patients over 19 months of study. One hundred twenty-two patients had serious injuries. The estimated systemwide overtriage and undertriage rates were 2.7 and 20.3 percent, respectively. Physiologic criteria had a 64.8 percent sensitivity and a 41.8 percent positive predictive value (PPV). The addition of anatomic criteria increased sensitivity to 82.8 percent and decreased PPV to 26.9 percent. Adding mechanism of injury increased sensitivity to 95.1 percent but further reduced PPV to 18.2 percent. Review of EMS records suggests that the addition of on-line medical control for patients in whom only the mechanism of injury triage guidelines apply could improve PPV with little effect on sensitivity. CONCLUSIONS: The current ACSCOT field triage guidelines are appropriate when applied by field EMS personnel.

Application of field triage guidelines by pre-hospital personnel: is mechanism of injury a valid guideline for patient triage?

We prospectively investigated the appropriateness of Mechanism of Injury as an exclusive indicator for trauma center triage. For all patients transported to our level 1 trauma center, EMS personnel identified applicable American College of Surgeons' Committee on Trauma field triage guidelines. A total of 112 questionnaires were completed. Mechanism of injury was the only reason for trauma center transport in 29. Neither intubation nor emergent surgery was required in any of these patients, and all survived. Only two had an ISS > 15. The remaining 83 patients had an 11% mortality rate. Fourteen (16.9%) had ISS scores > 15. Defining an ISS of 16 or greater as severe injury, mechanism of injury alone had a positive predictive value of only 6.9%. Mechanism of injury may not, by itself, justify bypass of local hospitals in favor of trauma centers.

In situ pulmonary vascular perfusion for improved recovery of pulmonary intravascular macrophages.

The microcirculation contains mononuclear phagocytes, with features characteristic of macrophages, adhered to luminal capillary surfaces by intercellular adhesion plaques. These pulmonary intravascular macrophages may play an important role in regulating lung vascular tone and capillary permeability, and may modulate capillary endothelial cell growth and replication by the secretion of soluble mediators (i.e., arachidonate metabolites, cytokines). This study describes a technique which utilizes in situ lung perfusion to remove intravascular macrophages in large numbers from the microcirculation of porcine lung (n = 26). This technique yielded 3.8 +/- 0.5 x 10(8) (mean +/- SEM) mononuclear cells which were highly phagocytic toward particulate carbon (phagocytic index, 80 +/- 6%). Harvested mononuclear phagocytes reestablished intercellular adhesion plaques when placed on small vessel porcine pulmonary artery endothelial cell monolayers and exhibited histochemical characteristics typical of monocyte/macrophage lineage cells. Mononuclear cells obtained from lung microcirculation displayed size heterogeneity varying from 10.4 to 16.5 microns in diameter. Both large and small cell populations phagocytosed particulate carbon. Morphometric studies performed on collagenase-treated lung demonstrated that in situ perfusion removed significant numbers of intravascular macrophages in lung capillaries. The technique described permits the rapid removal of anchored mononuclear phagocytes from lung capillaries with minimal postmortem delay.