Acute pancreatitis. Experimental evaluation of steroid, albumin and trasylol therapy

The efficacy of steroids, albumin and Trasylol administration in the treatment of experimental pancreatitis was evaluated. An isolated, ex vivo, perfused canine pancreas preparation was used and pancreatitis was initiated by free fatty acid infusion. Steroid administration worsened pancreatitis, Trasylol had no effect, and albumin was markedly effective in ameliorating pancreatitis. These results were interpreted as evidence against enzyme extravasation and for capillary injury as the initial step in the pathogenesis of pancreatitis.     

Aspiration pneumonia: a ten-year review.

Aspiration pneumonitis is an important cause of many anesthetic and non-surgical deaths and complication. One hundred and eight cases from 1964 to 1974 were reviewed to study the factors associated with aspiration pneumonia. Forty surgical and 68 non-surgical patients were evaluated and compared. Predisposing factors included impaired consciousness, esophageal and neurological disorders, cardiac resuscitation, debilitation, presence of a nasogastric tube or tracheostomy. The most common findings in both groups were dyspnea, cough, cyanosis, fever, tachycardia, rhonchi, rales and wheezes. Sputa of 64 patients failed to reveal the precise etiologic agent. High mortality (30%) and morbidity were found in both groups even with optimum treatment. The causes of morbidity in both groups of patients were pneumonia, lung abscess, myocardial infarction, gastrointestinal hemorrhage, and pulmonary embolus. Prevention, with particular attention to high-risk patients and to factors influencing aspiration in groups of surgical and non-surgical patients, is the solution to the problem.     

Aspiration pneumonia: beneficial and harmful effects of positive end-expiratory pressure.

With an ex vivo, isolated, ventilated, perfused canine pulmonary lobe, the effects of various levels of positive end-expiratory pressure (PEEP) were evaluated following acid injury. Following intrabronchial instillation of hydrochloric acid, eight lobes were ventilated with 5 cm of H2O of PEEP, 12 lobes with 10 cm of PEEP, and eight lobes with 15 cm of PEEP during a 4 hour perfusion period. Blood flow was kept constant in all preparations. Lobes with 5 cm of PEEP developed a 39% intrapulmonary shunt and increased their weight by 220%. When PEEP was increased to 10 cm, weight gain was similar (184%), but shunting decreased markedly, to 7%. When PEEP was increased further to 15 cm, shunting remained low (13%), but weight gain increased markedly, to 411% of the initial lobe weight. This study demonstrates the beneficial effects of PEEP in aspiration pneumonia, but it also points out that increasing levels of PEEP can magnify acid-pulmonary injury by causing a further increase in interstitial and intralveolar edema.     

Intraoperative fibrinolytic therapy: experimental evaluation

Percutaneous intra-arterial infusion of fibrinolytic agents has emerged as an alternative to embolectomy in selected patients with acute arterial occlusions. The combination of fibrinolytic therapy and embolectomy may be superior to either modality alone. This experiment was designed to determine safety and efficacy of intraoperative fibrinolytic therapy as an adjunct to catheter embolectomy. Forty hind limbs in 20 adult mongrel dogs were embolized with thrombus created in vitro. After 24 hours, bilateral transfemoral embolectomy was followed by intra-arterial, intraoperative infusion. Fifteen limbs (control) received 250 ml of saline solution during a 30-minute period; 25 limbs (experimental) received an arterial infusion of 60,000 units of streptokinase during a 30-minute period (SK 30'). In five limbs of each group, 500 units of heparin (H) was added. In five experimental limbs the streptokinase infusion time was increased to 60 minutes (SK 60'). Arteriograms and blood flow measurements were obtained before and after embolectomy (PE) and after infusion (PI); the results were compared. Improvement between the PE and PI angiograms was seen in 20% (3 of 15 dogs) of control subjects. In contrast, improvement after the infusion was evident in 100% (5 of 5 dogs) of dogs given SK plus H 30' (p less than 0.01), in 80% (12 of 15 dogs) of dogs given SK 30' (p less than 0.01), and in 20% (1 of 5 dogs) of dogs given SK 60'. A trend toward increased blood flow was noted in the experimental group. There were no intraoperative complications with hemostasis or postoperative bleeding (36-hour observation). We conclude that intraoperative fibrinolytic therapy in dogs is safe and effective as an adjunct to thromboembolectomy. A human clinical trial is recommended.     

Effect of steroid therapy in experimental head trauma

Since steroid therapy has been mostly utilized on an empirical basis in the management of head injury, this experimental study to assess the efficacy of steroid therapy was performed. Swiss-Webster mice (n = 85) were given 0.2 m of 50% ethanol intraperitoneally (IP) and lightly anaesthetized with ether. Ten randomly chosen mice were set aside and received no further treatment (non-head injury controls: Group A). The remaining mice (n = 75) were subjected to head injury and the survivors at 30 minutes (n = 52) were assigned randomly to two Groups, B and C. Group B was given 0.1 ml of saline IP at 30 minutes, 28 hours and 48 hours post-injury. At similar time intervals, animals in Group C received methylprednisolone 30 mg/kg IP. All animals were observed up to seven days and the number of survivors in each group recorded. All ten animals in Group A survived seven days. The daily mortality in Groups B and C were similar, and all animals were dead at seven days. Steroids were not found to be efficacious in this animal model.     

Aspiration pneumonia: Incidence of aspiration with endotracheal tubes

Aspiration has been suggested as a source of pulmonary complications seen in patients with tracheal intubation. A previous study demonstrated that the high incidence of aspiration in patients with tracheostomies can be decreased by modification of the tracheostomy tube cuff design. In the present protocol, 100 patients with endotracheal tubes in place were studied to document the incidence of aspiration and to attempt to decrease the incidence by modification of cuff design. Utilizing an Evans blue dye test to detect aspiration, 27 of the 48 patients (56 per cent) with standard low volume, high pressure cuffed tubes had positive tests. In 17 patients with modified standard cuffed tubes, the incidence of aspiration was decreased to 29 per cent (5 patients). Aspiration was further decreased to 20 per cent (7 patients) in the 35 patients with high volume, low pressure cuffed tubes. These results demonstrate that the incidence of aspiration in patients with endotracheal tubes can be decreased by modification of endotracheal tube cuff design.     

Aspiration pneumonia. Prevention of aspiration in patients with tracheostomies

Previous work has documented the incidence of aspiration in patients with tracheostomies to be very high. This has been suggested as a reason for the frequent pulmonary complications seen in patients with tracheostomies. In this study, two modified tracheostomy tube cuffs were evaluated as to their ability to act as a mechanical barrier and prevent aspiration. Forty spontaneously breathing patients with tracheostomies were studied. Utilizing an Evans blue dye test for aspiration, 13 (87%) of the 15 patients with standard tracheostomy tubes aspirated. Aspiration in the two study groups in which modified tracheal cuffs were used was decreased to 17% (2/12) and 15% (2/13). It is suggested that by proper tracheostomy cuff design, the high incidence of aspiration in patients with tracheostomies can be decreased.     

Histology and immunohistochemical evaluation of phimotic prepuce: The role of steroid therapy

Phimosis is one of the most frequent andrological diseases in paediatric age. Steroids are useful to treat phimosis. Through a retrospective study of histological and immunohistochemical analysis, we evaluated the effectiveness of topical steroid treatment in patients undergoing circumcision. Cases of patients treated for phimosis were selected during the two-year study period. All patients underwent circumcision and were divided into four groups: groups A (religiously circumcised patients), B (phimotic patients not undergoing steroid treatment), C (phimotic patients who do not respond to cortisone treatment) and D (hypospadic patients undergoing urethroplasty). An histological evaluation of the degree of fibrosis and an immunohistochemical evaluation of collagen IV and tenascin were carried out. Study results demonstrate that the grade of fibrosis is age-related. On histological and immunohistochemical evaluation, fibrosis was found to be lower in patients receiving steroids; higher degrees of fibrosis were found in older patients (p < .05). Different degrees of fibrosis have also been found in hypospadic patients. We can conclude that study results correlated with the clinical history of the patients. The success rate of medical therapy seems to be age-related.     

Aspiration pneumonia and the laryngeal mask airway

A case of aspiration pneumonia is reported after the use of a laryngeal mask airway in a young woman undergoing an elective cholecystectomy. The case illustrates the hazards of regurgitation with the laryngeal mask airway and the need for further evaluation when used with controlled mechanical ventilation.     

Donor-transmitted pneumonia in experimental lung allografts. Successful prevention with donor antibiotic therapy.

Bacterial pneumonia is the most common cause of early morbidity and mortality (less than 2 weeks) after heart-lung transplantation. The majority (76%) of cultures taken from human donor tracheas at the time of explant grew bacteria. The abnormal immune response of the lung allograft and the common finding of bacterial contamination of lung donors led us to hypothesize that clinically silent bacterial contamination of the donor lung progresses to pneumonia in the recipient and that antibiotic treatment of donors will prevent the development of pneumonia in the recipient. Inocula of Streptococcus pneumoniae were instilled into the left middle lobe of normal and donor dogs to identify the number of bacteria that would result in pneumonia in a normal animal and the amount that, when given to a donor, would result in pneumonia in the recipient. Initial studies established that inocula of 10(4) colony-forming units of S. pneumoniae did not result in pneumonia in normal or immunosuppressed animals. When 10(4) colony-forming units or as few as 10(2) were instilled into the left middle lobe of donors 24 hours before explantation and use of the lung for transplantation, severe acute bronchopneumonia developed in all 18 recipients. Treatment of donors with aerosol and intravenous antibiotics, but not with either alone, prevented pneumonia in the recipients. We conclude that bacterial contamination of the donor lung leads to pneumonia in recipients. Intravenous and aerosol antibiotic treatment of donors with bacterial contamination prevents pneumonia in canine lung recipients. Treatment of human donors with this antibiotic regimen may decrease the prevalence of early bacterial pneumonia.