Operative videothoracoscopy in the surgical treatment of penetrating firearms wounds of the chest

We prospectively analyzed our experience with operative videothoracoscopy (OVT) performed in a field military hospital in cases of penetrating firearms wounds of the thorax (PFAWT) sustained in Chechnya. From February to April 1996, we treated 206 wounded patients, of whom 37 (18.0%) had sustained chest injuries. PFAWT were present in 23 soldiers, accounting for 62.2% of all chest injuries. Twelve injuries were confined to the thorax, eight patients had associated injuries, and three soldiers had thoracoabdominal injuries. Nineteen patients had pleural drainage performed during medical evacuation. The thoracic injuries were right-sided (17), involved bullets or shell splinters (23); were through and through (16), represented solitary wounds (19), and were associated with internal organ injuries (21). Fifteen patients had indications for OVT when they were delivered from the battle-field 1.5 to 22 hours after injury. All patients manifested signs of hemorrhagic shock and hemodynamic instability. Indications for OVT were ongoing intrapleural bleeding (6), clotted hemothorax (6), or marked air leakage (3) preventing lung inflation with the OP-02 apparatus (field modification). OVT revealed 12 lung wounds, nine of which were multiple wounds, pleural bleeding in 6 patients, clotted hemothorax in 11 patients, and foreign bodies in 5 patients. Two patients underwent thoracotomy, one for suspicion of heart injury and the second because we could not adequately visualize and control bleeding revealed at OVT to be from the intercostal artery in the left costovertebral angle. Eight of 23 patients had no indication for operative videothoracoscopy and were managed with continued pleural aspiration and drug therapy. Wedge resection of the lung using an Endo-GIA-30 stapler was necessary in two patients because of parenchymal destruction and bleeding. Evacuation of clotted blood by fragmentation and aspiration was satisfactory in all cases. Satisfactory manual suturing of selected lung injuries was obtained largely with intracorporeal knot tying. The duration of the procedures ranged from 40 to 90 minutes. No morbidity nor mortality was encountered in patients undergoing OVT. Postoperative pain was minimized by using OVT placement of catheters in the chest wall soft tissue with local administration of 2% Trimecain. Patients were able to stand in 10 to 12 hours and to walk by the end of the first postoperative day. All patients who underwent OVT were evacuated without drains by the third or fourth postoperative day, all tolerating sitting and standing positions. We conclude that early OVT in the military field hospital for continued bleeding, clotted hemothorax, and continued major air leakage has several advantages in military patients with PFAWT: early definition and management of organ injury; identification and control of bleeding in most instances; earlier and more accurate assessment for thoracotomy; vigorous lavage and removal of projectiles such as bone fragments and evacuation of clotted hemothorax; early debridement with suture closure of the thoracic wall canal; and minimal postoperative pain with dramatically reduced suppurative sequelae and bronchopleural fistulae.     

Measurement of myocardial blood flow with oxygen-15 labelled water: comparison of different administration protocols

Positron emission tomography (PET) in conjunction with C15O2 or H215O can be used to measure myocardial blood flow (MBF) and tissue fraction (TF), i.e. the fraction of the tissue mass in the volume of the region of interest. However, with C15O2 inhalation, the tissue fraction in the septum is overestimated. Bolus injection of H215O together with arterial cannulation gives very precise results but is invasive. The purpose of this study was to develop a method which circumvents these problems. A four-parameter model with parameters for MBF, TF and spill-over fractions from both left and right ventricular cavities was developed. This method was compared with a three-parameter model (no right ventricular cavity spill-over) in both septal and non-septal regions of interest for three different administration protocols: bolus injection of H215O, infusion of H215O and inhalation of C15O2. It was found that MBF can be measured with intravenous administration of H215O without the requirement for arterial cannulation. The four-parameter protocol with bolus injection was stable in clinical studies. The four-parameter model proved essential for the septum, where it gave highly significantly better fits than did the three-parameter model (P<0.00003 in each of 15 subjects). Administration of H215O together with this four-parameter model also circumvented the problem of overestimation of TF in the septum seen with C15O2 inhalation. In addition, the radiation dose of H215O protocols is lower than that of C15O2 inhalation. Using a left atrial input curve instead of a left ventricular cavity input curve gave the same mean MBF and TF.     

Secondary prevention of ischemic heart disease after coronary revascularization

This study was aimed to assess the compliance with policies for secondary prevention of coronary heart disease (CHD) one year after coronary artery revascularization with special attention to the management of hyperlipidemia. One year after coronary revascularization during the year 1994, patients were contacted by letter to determine the modification of their risk factors, the treatment patterns for hypercholesterolemia and to have their plasma lipid level and blood pressure measured. Of the 245 consecutive patients contacted (110 after coronary artery bypass grafting, and 135 after percutaneous transluminal coronary angioplasty), 186 (76%) provided the information required for further analysis. Excluding the patients older than 65 years, only 29 out of 97 patients (30%) with a total cholesterol of more than 5.2 mmol/l, and only 20 out of 52 patients (38%) with a total cholesterol of more than 6.2 mmol/l were receiving lipid lowering therapy 1 year after coronary artery revascularization. In contrast, 97% (n = 180) of the entire population studied were taking antiplatelet drugs and/or coumadine. Participation in an in-house rehabilitation program yielded a positive influence on smoking, but not on treatment of hypercholesterolemia. In conclusion, only a small proportion of patients with documented CHD and hypercholesterolemia were being treated for their lipid disorder 1 year after coronary artery revascularization. In contrast, the great majority of patients received antiplatelet and/or coumadine therapy: These results indicate that the compliance with published treatment guidelines for hyperlipidemia in patients with CHD is still highly inadequate, irrespective of the participation in a rehabilitation program.     

Stochastic response surface methods (SRSMs) for uncertainty propagation: application to environmental and biological systems

Indicators of self-efficacy and motivation to change (stage of change) with regard to drinking and to drinking and driving were examined in a sample of Driving Under the Influence (DUI) offenders in a court-mandated intervention program. Self-administered questionnaires that contained pertinent measures were completed by 210 consenting offenders (34 of whom were female) during the intervention program. A factor analysis of efficacy and stages of change items showed distinct factors for the respective constructs; however, drinking and drinking-and-driving items of the same type (e.g., efficacy or stages of change) tended to codefine common factors, and the factor pattern suggested that motivations and efficacy for changing drinking behavior are critical for avoiding the drinking-and-driving sequence. Most participants were classified into the action stage in both drinking and drinking-and-driving domains. In regression analysis, contemplation of action and self-efficacy measures pertaining to drinking and driving predicted prior crashes and arrests; however, after accounting for recent alcohol problems, action items pertaining to drinking and driving were the best predictors of recent drinking-and-driving incidents.     

Virus-specific CD8(+) T cell numbers are maintained during gamma-herpesvirus reactivation in CD4-deficient mice

The murine gamma-herpesvirus 68 replicates in epithelial sites after intranasal challenge, then persists in various cell types, including B lymphocytes. Mice that lack CD4(+) T cells (I-Ab-/-) control the acute infection, but suffer an ultimately lethal recrudescence of lytic viral replication in the respiratory tract. The consequences of CD4(+) T cell deficiency for the generation and maintenance of murine gamma-herpesvirus 68-specific CD8(+) set now have been analyzed by direct staining with viral peptides bound to major histocompatibility complex class I tetramers and by a spectrum of functional assays. Both acutely and during viral reactivation, the CD8(+) T cell responses in the I-Ab-/- group were no less substantial than in the I-Ab+/+ controls. Indeed, virus-specific CD8(+) T cell numbers were increased in the lymphoid tissue of clinically compromised I-Ab-/- mice, although relatively few of the potential cytotoxic T lymphocyte effectors were recruited back to the site of pathology in the lung. Thus the viral reactivation that occurs in the absence of CD4(+) T cells was not associated with any exhaustion of the virus-specific cytotoxic T lymphocyte response. It seems that CD8(+) T cells alone are insufficient to maintain long-term control of this persistent gamma-herpesvirus.     

Evaluation of the ability of power to predict low frequency lifting capacity

An experiment was conducted to examine the role that maximal lifting power has in predicting maximum acceptable weight of lift (MAWL) for a frequency of one lift per 8 h. The secondary aim of the study was to compare the ability of power to predict MAWL to previously used measures of capacity including two measures of isometric strength, five measures of isokinetic strength, and isoinertial capacity on an incremental lifting test. Twenty-five male subjects volunteered to participate in the experiment. The isometric tests involved maximum voluntary contractions for composite lifting strength at vertical heights of 15 and 75 cm. Peak isokinetic strength was measured at velocities of 0.1, 0.2, 0.4, 0.6 and 0.8 m s-1 using a modified CYBEX II isokinetic dynamometer. Isoinertial lifting capacity was measured on the X-factor incremental lifting machine and peak power was measured on the incremental lifting machine by having subjects lift a 25 kg load as quickly as possible. The results indicate that peak isoinertial power is significantly correlated with MAWL, and this correlation was higher than any of the correlations between the other predictor variables and MAWL. The relationships between the isokinetic strength measures and MAWL were stronger than the relationships between the isometric measures and MAWL. Overall, the results suggest that tests used to predict MAWL should be dynamic rather than static.     

A novel Asn344 deletion in the core domain of coagulation factor XIII A subunit: its effects on protein structure and function

We re-evaluated three schemes of liver organization: the classic lobule, the portal lobule, and Rappaport's liver acinus. The lobular angioarchitecture of normal rat liver and the three-dimensional structure of pseudolubules found in rat livers with fibrosis induced by swine serum were compared with the classic lobule of the pig. Normal and fibrotic rat livers and pig livers were perfused, injected with either India ink or 0.75% OsO4 through the portal and/or hepatic vein, and immersionfixed. Whole lobes and hand-cut thick sections were made transparent with a solution of benzyl benzoate and methyl salicylate. The angioarchitecture of normal rat liver differs from pig liver. In the former, terminal portal branches and central veins interdigitate, and in the latter, numerous terminal portal branches that arise from interlobular portal veins establish a vascular basket surrounding one central vein and forming classic lobule. The structure of liver acinus is never found in the pig liver. The terminal portal branch, together with the terminal hepatic artery and bile duct, are present inside each pseudolobule of fibrotic rat livers. Blood from the terminal portal branch flows through inlet venules into radiating sinusoids, and, at the periphery converges into newly formed septal and angular outlet venules; these venules terminate in fibrotic central veins located at each corner. Pseudolobules are not rugby ball-like as Rappaport's liver acini are but are polyhedron in shape. The rat pseudolobules are comparable with the portal lobule; its structure and microcirculation are the reverse of the pig classic lobule. Rat pseudolobules are different from liver acini, as shown by the following: 1) their three-dimensional shape is different; and 2) they have a reverse relationship to classic lobules while acini are defined to subdivide classic lobules. In normal and fibrotic rat livers, the liver unit is the portal lobule with a terminal portal branch as the axial branch and central veins at the periphery. The co-existence of liver acini and classic lobules is doubtful.