Risk factors for early-onset, ventilator-associated pneumonia in critical care patients: selected multiresistant versus nonresistant bacteria

BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.     

Diagnosis and treatment of hepatic artery thrombosis after liver transplantation

The aim of this study was to examine the clinical presentation and time of hepatic artery thrombosis (HAT) after orthotopic liver transplantation (OLT), stressing the role of imaging modalities. Therapeutic options are described, such as retransplantation (Re-OLT), hepatic resections and revascularization procedures, focusing on complications and outcome in a consecutive series of 687 OLT. Over the period from 1986 to 1999, 687 OLT were carried out in 601 patients, 592 of whom were adults and 95 pediatric subjects. Of these operations 601 were primary OLT and 86 Re-OLT (71 I Re-OLT, 14 II Re-OLT and 1 III Re-OLT). In this retrospective study, we reviewed rejection episodes, time of HAT (early or late), possible cause of HAT, day of suspected diagnosis of HAT and day of confirmation of diagnosis. Clinical presentation, management, complications, outcome, survival rates and the need for Re-OLT were also recorded. The incidence of HAT was 2.47% (17/687). Early HAT (n = 9, < 30 days) was diagnosed 15.6 days after OLT (range: 3-25 days), whereas late HAT (n = 8, > 30 days) occurred 295.1 days after OLT (range: 38-1830 days). In two asymptomatic patients (2/17: 11.7%), HAT was discovered incidentally. Most of the patients (11/17: 64.7%) presented with increased liver function test values and fever. Relapsing bacteremia occurred in 7/17 cases (41.1%), whereas a biliary stricture and biliary leak were diagnosed in 3/17 (17.6%) and in 1/17 patients (5.8%), respectively. Fulminant hepatic failure was the clinical presentation in 2/17 cases (11.7%). In one case the clinical presentation was acute and chronic rejection (1/17: 5.8%). Intrahepatic abscesses were diagnosed in one case (1/17: 5.8%), as well as an intrahepatic haemorrhage (1/17: 5.8%). Doppler ultrasound (DUS) correctly revealed HAT in 9 of the 17 patients (52.9% sensitivity). In 8 of the 9 patients (88.8%) in whom HAT was diagnosed by DUS, angiography was also performed to confirm the diagnosis. Overall, angiography detected HAT in 14/17 patients (82.3% sensitivity). HAT management consisted of immediate Re-OLT in 6 patients 6.8 days (range: 3-12 days) after diagnosis. Delayed Re-OLT was performed in 6 patients 529.1 days (range: 68-1920 days) after diagnosis. The overall retransplantation rate was 70.5% (12/17). Two patients died despite undergoing intraarterial urokinase treatment. Three grafts were salvaged, but suffered biliary stricture due to ischemic cholangitis and underwent hepatico-jejunostomy. A II Re-OLT was carried out in 4 of 12 patients (33.3%). The overall mortality rate was 41.1% (7/17). One-year and 3-year overall survival rates were 58.8% (10/17) and 47.0% (8/17), respectively. Both 5- and 10-year overall survival rates were 11.7% (2/17). Although the results of OLT have improved dramatically over the past few years, HAT is still associated with substantial morbidity, a high incidence of graft failure and high mortality rates. The use of DUS to screen for HAT has permitted earlier diagnosis, but early angiographic evaluation of the hepatic arteries is still needed for accurate diagnosis of HAT and remains the gold standard. Retransplantation is the definitive solution for HAT in the majority of cases, though it is essentially the patient's clinical condition that dictates the form of management.     

Forensic identification of skeletal remains from members of Ernesto Che Guevara’s guerrillas in Bolivia based on DNA typing

We report the positive identification of several members of the guerrillas led by Ernesto “Che” Guevara on the 1960 s in Bolivia by means of DNA fingerprinting. Successful DNA typing of both short tandem repeat loci and the hypervariable region of the human mitochondrial DNA was achieved after extracting total DNA from bones obtained from two burial sites. Given the size of the Cuban database for the STR allele frequencies, a conservative approach was followed to estimate the statistical significance of the genetic evidence. The estimated probabilities of paternity for the two cases in which the paternity logic was applied were higher than 99%. One case was analyzed using mitochondrial DNA and could not be excluded from the identity proposed by the forensic anthropology team. A fourth case was identified by exclusion, on the basis of the positive identification of the other remains, the historical and other anthropological evidence. Received: 19 January 1999 / Received in revised form: 15 April 1999     

Current management of calculi in horseshoe kidneys

OBJECTIVES: To assess treatment options for calculi in horseshoe kidneys and the impact of extracorporeal shockwave lithotripsy (ESWL) on the management of renal stones. MATERIAL AND METHODS: From June 1971 to January 1998, 52 patients with horseshoe kidneys and calculi received treatment at our Urologic Stone Unit. There were 40 men (77%) and 12 women (23%). Average patient age was 41 years (range: 10-70 years). Clinical onset, treatment received and outcome were evaluated retrospectively. A successful outcome was defined as a patient without residual calculi or with fragments <0.4 cm in size. RESULTS: Clinical onset was mainly low back pain in 37 patients (71%). Eighty-nine stones were treated, i.e. an average of 1.7 treatments per patient. Before the ESWL era (May 1987), we performed two heminephrectomies, 16 pyelolithotomies, 12 pyelolithotomies combined with ureteropyeloplasty and one percutaneous nephrolithotomy. Since the advent of ESWL, seven pyelolithotomies and three pyelolithotomies combined with ureteropyloplasty have been done. ESWL was used to treat 48 calculi. In three cases the patient was placed in the prone position due to difficulties in stone focusing. In 37 cases (77%) patients were either rendered stone-free or had residual fragments <0.4 cm in size. Urinary diversion for obstruction was carried out in two cases (4%). CONCLUSIONS: At present ESWL is the first-choice treatment for calculi in horseshoe kidneys. It involves no significant focusing difficulties and is associated with a low incidence of obstructive complications. Open surgery is indicated in cases of stone-related pyeloureteral stenosis and in the presence of calculi >2-2.5 cm in size.     

Tetraplegia in the immediate postoperative period of stapedectomy

Management of the cervical spine in orotracheal intubation for general anesthesia is an important aspect of daily practice in anesthesiology. Also important are the requirements, techniques and consequences of patient position during surgery. We report a case of tetraplegia during the early postoperative period after stapedectomy for otosclerosis. After surgery, the spontaneously breathing patient was transferred to the recovery room, where a clinical picture of anesthesia and paralysis of all four limbs was evident. We ordered an emergency magnetic resonance image of the cervical spine, which revealed a massive acutely herniated disk at C6-C7 with signs of ischemia or necrosis of the medulla at the same level. After eight months, the patient was still paraplegic and lacked sensation in the lower limbs. Sensation and motor function in the upper limbs was nearly normal. We review the etiopathogenetic mechanisms that might be responsible for this clinical profile.     

Locoregional anesthesia for external ear surgery and postoperative analgesia

OBJECTIVES: To evaluate a change in the classical technique for local-regional anesthesia (periauricular "V" infiltration) for surgery on the outer ear, specifically adding a new infiltration of the osteocartilaginous juncture of the external acoustic meatus and the auditory foramen, as an alternative to general anesthesia in adults, including assessment of postoperative analgesia. PATIENTS AND METHODS: The new technique was used in 45 operations on 23 patients. We analyzed pain during and after surgery on a simple verbal scale. RESULTS: After modifying the technique it was possible to perform surgery on the outer ear without causing pain, patients reporting "0" pain on a scale of 0 to 10. Eight patients reported "0" for postoperative pain, while one assessed pain as "4" and one as "2". No signs of emesis or cardiac events were observed. CONCLUSIONS: The described local-regional blockade of the outer ear used as the only anesthetic method, is indicated for both cosmetic surgery and repair of outer ear injuries, given its excellent analgesia during and after surgery. The characteristics of this type of block of the pavilion make it ideal for major outpatient surgery and a valid alternative to general anesthesia in adults.     

Reduction of blood transfusion need with aprotinin in orthopedic surgery. Spanish Study Group on the Use of Aprotinin in Hip Arthroplasty (GEEEAAC)

Aprotinin is a protease inhibitor of interest for its antifibrinolytic effect of reducing perioperative bleeding in certain types of surgery, with wide use in heart surgery, liver transplantation and vascular surgery. The application of aprotinin during orthopedic surgery has recently been suggested. Such use is controversial, as there is lack of consensus as to the type of patient for whom aprotinin administration would be indicated, the surgical procedure during which it would be most effective (hip or knee arthroplasty, spinal arthrodesis, major tumor or septic surgery), the doses to administer, its safety and its real efficacy for conserving homologous blood. That is to say, there is no agreement as to the cost/benefit relation of aprotinin for the various types of orthopedic surgery. This critical review of the literature leads to the conclusion that aprotinin is a promising drug for use in orthopedic surgery, given that published studies have established the benefit in blood product savings and decreased blood loss during surgery.     

Descending necrotizing mediastinitis

Between 1990-1999, six patients (mean age, 41.5 years) with the diagnosis of descending necrotizing mediastinitis were surgically treated at our institution. All patients underwent cervical drainage plus an aggressive mediastinal debridement and drainage via posterolateral thoracotomy. The outcome was favorable in all cases. All patients received initially a high dose of broad-spectrum antibiotics. In four patients, a tracheostomy was necessary for respiratory management. We also review the literature.