Intensive care management of varicella pneumonia.

To determine the clinical features, treatment and outcome of severe varicella pneumonia with hypoxic respiratory failure requiring intensive care management, a prospective survey of consecutive cases was undertaken. Fifteen consecutive adult cases of varicella pneumonia with respiratory failure admitted to a 10-bed respiratory intensive care unit over a period of 10 y from 1984-1993 were studied. All patients were given acyclovir immediately on admission. The level of ventilatory support needed was determined by the severity of gas exchange abnormality, and varied from face mask oxygen (three patients), through continuous positive airway pressure (CPAP) by face mask (eight patients), to continuous positive pressure ventilation (CPPV) (four patients). The majority of patients were young females, only one of whom was pregnant. All patients had been in close contact with a known case of chickenpox. All patients responded well to acyclovir and ventilatory support with improved oxygenation. Monitoring with pulse oximetry was important to detect episodes of desaturation on inadvertent discontinuation of positive and expiratory pressure (PEEP). Two patients were admitted with bacterial superinfection, and one patient, who had required intubation and CPPV, developed nosocomial respiratory tract infection. There were no deaths. This experience suggests that intensive care admission, with the early administration of intravenous acyclovir and recognition of the severity of the hypoxaemia resulting from varicella pneumonia (which can be reversed with PEEP), should reduce the mortality of severe varicella pneumonia in adults.

The intensive care management, mortality and prognostic indicators in severe community-acquired pneumococcal pneumonia.

OBJECTIVE: To determine mortality and factors that might predict outcome in severe community-acquired pneumococcal pneumonia treated by a standard protocol. DESIGN: Prospective, non-concurrent study. SETTING: Respiratory intensive care unit (ICU) in a teaching hospital. PATIENTS: 63 patients who were diagnosed by positive blood culture or Gram stain and culture of sputum or tracheal aspirate were included. MEASUREMENTS AND RESULTS: Clinical features, severity scores including Acute Physiology and Chronic Health Evaluation (APACHE) II, organ failure and lung injury scores, and the clinical course in the ICU were documented; 79% of patients required mechanical ventilation. Bacteraemia was present in 34 patients (54%); there were no distinguishing clinical features between bacteraemic and non-bacteraemic cases. The overall mortality was 21%, with only 5 deaths (15% mortality) in the bacteraemic group. Shock and a very low serum albumin (< 26 g/l) were the only clinical features that differentiated survivors from non-survivors; lung injury, APACHE II and multiple organ failure scores were all predictive of outcome. The positive predictive value and specificity in predicting death in individuals for the modified British Thoracic Society rule 1 were 26 and 64%; APACHE II > 2057 and 88%; > 2 organ failure 64 and 92%; and lung injury > 233 and 73%, respectively. CONCLUSIONS: These results suggest that even in bacteraemic cases mortality should be below 25% with intensive care management and that conventional scoring systems, while predictive of group mortality, are unreliable in individuals.

The influence of surgery on cytokines in patients with intra-abdominal sepsis.

The cytokine cascade which is triggered by severe sepsis may contribute to progressive organ dysfunction and death from sepsis. This cascade may be accentuated by surgery for sepsis and pre-treatment with cytokine blockers could possibly ameliorate the response. This prospective controlled study determined the effect of surgery in 11 haemodynamically stable patients undergoing laparotomy for intra-abdominal sepsis. Serum levels of endotoxin, IL-1, IL-6, IL-8 and TNF-alpha were determined; blood cultures, features of systemic inflammatory response, and organ dysfunction were monitored over the peri-operative period. There was considerable variation in the serum cytokine levels. The preoperative IL-6 levels were significantly elevated in the septic patients and a threefold increase in IL-6 levels occurred in both groups postoperatively. An increase in TNF-alpha did not achieve significance because of high levels in control patients with cancer. Cytokine release which occurs during abdominal surgery is increased in patients with intra-abdominal sepsis.

The etiology and antimicrobial susceptibility patterns of microorganisms in acute community-acquired lung abscess.

OBJECTIVE: To determine the spectrum and antibiotic susceptibility patterns of microorganisms causing acute community-acquired lung abscess. DESIGN: A prospective survey. SETTING: Medical emergency department and wards of a tertiary teaching hospital. PATIENTS: Thirty-four adult patients with both clinical and radiologic features compatible with a diagnosis of acute community-acquired lung abscess who had received less than 48 h of antibiotic therapy. INTERVENTIONS: Microbiologic specimens obtained by percutaneous lung aspiration and with a protected specimen brush via fiberoptic bronchoscopy were submitted for aerobic and anaerobic culture. MAIN OUTCOME MEASURES: Identification of all microorganisms, including anaerobes, and determination of antibiotic susceptibility. RESULTS: A mean of 2.3 bacterial species per patient was isolated, anaerobes alone being isolated in 44% of cases, aerobes alone in 19%, and mixed aerobic and anaerobic isolates in 22%. Aerobic Gram-negative pathogens were uncommon. In seven patients, Mycobacterium tuberculosis was identified; in two it was associated with other bacteria. In four patients, no organisms were isolated. All the nonmycobacterial isolates were susceptible to amoxicillin-clavulanate and in addition the anaerobes were all susceptible to chloramphenicol and almost all to a combination of penicillin and metronidazole. Among the anaerobes, the level of resistance to penicillin, metronidazole, and clindamycin individually was 21%, 12%, and 5%, respectively. CONCLUSIONS: Community-acquired acute lung abscess is usually caused by multiple anaerobic and less frequently aerobic Gram-positive microorganisms, which should respond to empirical therapy with amoxicillin-clavulanate, chloramphenicol, or a combination of penicillin and metronidazole. Tuberculosis, which may be indistinguishable from an acute lung abscess, occurred in 21% of patients in our study. Most bacterial pathogens are sensitive to conventional antimicrobial therapy and further investigation with percutaneous lung aspiration or bronchoscopy is indicated only when there is lack of early response to therapy or there is the presence of atypical clinical features.

Long-term effects of selective decontamination on antimicrobial resistance.

OBJECTIVE: To determine whether selective decontamination of the digestive tract exerts any long-term effects on antimicrobial resistance patterns. DESIGN: A surveillance and interventional study comparing the antimicrobial sensitivity patterns of clinically important bacterial isolates the year before a 2-yr, double-blind, randomized, controlled study of selective decontamination of the digestive tract, and for the year thereafter when no use of the regimen was made. SETTING: A ten-bed respiratory intensive care unit (ICU) in a 1,200-bed teaching hospital. PATIENTS: All 1,528 patients admitted to the ICU over the 4-yr study period were included. There were 406 patients admitted in the year before the study of decontamination of the digestive tract (65% medical, 23% surgical, and 12% trauma), of whom 76% required mechanical ventilation. There were 719 patients admitted during the 2-yr study of selective decontamination (55% medical, 28% surgical, and 17% trauma), of whom 79.6% required mechanical ventilation. There were 403 patients admitted in the subsequent year (61% medical, 25% surgical, and 14% trauma), of whom 76.9% required mechanical ventilation. INTERVENTIONS: We performed daily clinical monitoring to detect nosocomial infection, with microbiological investigation when clinically indicated, as well as twice-weekly routine microbiological surveillance sampling. Antimicrobial susceptibility testing using standard laboratory methods was also performed. Selective decontamination of the digestive tract included parenteral cefotaxime and oral and enteral polymyxin E, amphotericin B, and tobramycin. MEASUREMENTS AND MAIN RESULTS: The occurrence rate of nosocomial infection was 20.6%, 16.6%, and 25.3%, respectively, in the three study periods. In the year after selective decontamination, there was an increase in the occurrence rate of infection (p = .005), with an-associated increase in infections caused by the Enterobacteriaceae, while a reduction in the level of resistance to the third-generation cephalosporins were found (p = .07). There was a progressive increase in the occurrence rate of infections caused by Acinetobacter species (p = .05). Only 11 infections over the 4 yrs were caused by Enterococcus species. Staphylococcal infections were uncommon (5.7% of admissions), and the level of methicillin resistance did not change. No increase in aminoglycoside resistance occurred. CONCLUSION: No long-term effects on antimicrobial resistance or the spectrum of nosocomial pathogens could be attributed to the use of selective decontamination of the digestive tract over a 2-yr period in a respiratory ICU admitting all categories of patients.

Is there a role for selective decontamination of the digestive tract in primarily infected patients in the ICU?

The role of selective decontamination of the digestive tract (SDD) for the prevention of nosocomial infection in critically ill patients remains controversial, and the efficacy of this technique in patients who are already infected on presentation to the intensive care unit has not previously been assessed. We performed a double-blind randomized placebo controlled trial of SDD (parenteral cefotaxime, six-hourly oral and enteral polymyxin E, tobramycin, and amphotericin B vs placebo) for all infected patients presenting to the ICU requiring mechanical ventilation for more than 48 hours and ICU stay of more than 5 days. Daily clinical and microbiological monitoring for secondary infection was undertaken until hospital discharge. In all, 59 selective decontamination and 76 placebo fully comparable patients fulfilled criteria for enrollment and analysis (APACHE II 15.2 vs 15.1). The number of patients receiving SDD who developed nosocomial infections was significantly reduced (P = 0.048), and there were no infections caused by the enterobacteriaceae or Candida spp in this group. No difference in ICU (17.5 vs 18.8 days) or hospital stay (32.7 vs 34.2 days) or mortality (17% vs 22.3%) was shown. Critically ill, primarily infected patients are protected from nosocomial infection by the use of SDD.

Prophylactic use of the new quinolones for prevention of nosocomial infection in the intensive care unit.

The new quinolone antimicrobial agents, particularly those with less activity against anaerobes, selectively prevent colonisation of the alimentary tract by Gram-negative bacilli and staphylococci without substantially affecting the normal anaerobic flora, which preserve the colonisation resistance of the gut. These properties ideally position this class of antibacterial agent for selective decontamination of the digestive tract (SDD) in the prevention of nosocomial infection. The rationale for this procedure is based on the presumption that a significant proportion of infections in compromised patients are endogenous in origin, arising from the host's own microbial flora. If this colonisation by potentially pathogenic microflora within the normal flora can be significantly reduced without being replaced by other more pathogenic microorganisms, the risk of endogenous infection should be minimised. The quinolones have proved to be ideal agents for use in preventing infection in bone marrow transplant and other neutropenic patients. They have been used for SDD in the general intensive care unit population, although the technique has not received widespread acceptance. There have been only 4 reported randomised studies using quinolones as part of SDD regimens and only 301 patients have been evaluated. Although the incidence of ventilator-associated pneumonia has been significantly reduced from 36 to 15%, no effect has been shown on mortality. The cost of using SDD is significantly less with the quinolones than with other regimens, and induction of resistance has not been noted. The new quinolones, and in particular the more recently developed agents with extended Gram-positive activity, appear to be ideally suited for SDD, and their careful evaluation in further large, well designed trials is warranted.

Automatic weaning from mechanical ventilation using an adaptive lung ventilation controller.

STUDY OBJECTIVE: To evaluate a new method of closed-loop mechanical ventilation using an adaptive lung ventilation (ALV) controller in patients with different pathologic causes of respiratory failure at a time when they first met standard weaning criteria. STUDY DESIGN: Prospective, open, selected case study. SETTING: The 10-bed, multidisciplinary respiratory intensive care unit at Groote Schuur hospital, which is a teaching unit of the University of Cape Town. PATIENTS: Twenty-seven patients (9 patients in each of 3 groups: normal lungs, parenchymal lung disease, and COPD) who required prolonged mechanical ventilation and who met standard weaning criteria were included. Our institutional committee for ethical research approved the study and informed consent was obtained. INTERVENTIONS: The patients were mechanically ventilated and had daily measurements of vital capacity, respiratory rate, and arterial blood gas analysis until they met standard weaning criteria. On the day that each patient met the weaning criteria, a closed loop control algorithm providing ALV was implemented on a modified ventilator (Hamilton AMADEUS) with a PC-based lung function analyzer. After measuring gross alveolar ventilation, patients were placed in ALV and ventilatory and hemodynamic parameters were measured at baseline, 5 min, 30 min, and 2 h. Pertinent parameters measured included airway pressures, pressure support levels, respiratory rates, rapid shallow breathing indices, airway resistance indices, and patient respiratory drive and work indices. MEASUREMENTS AND RESULTS: In 22 patients, ALV reduced pressure support to 5 cm H2O and an intermittent mandatory ventilation rate of 4 breaths/min within 30 min, and all but 1 of these patients were successfully extubated within 24 h. In four patients, pressure support was maintained by ALV at a mean level of 14.6 cm H2O +/- for 2 h and these patients were recorded as having failed to wean. There was a measurable difference in an index of airway resistance relative to muscular activity between the successfully weaned and failed wean patients with COPD during the attempted wean by the ALV controller. CONCLUSIONS: ALV will provide a safe, efficient wean and will respond immediately to inadequate ventilation in patients when standard weaning criteria are met.

Fatal Capnocytophaga canimorsus (DF-2) septicaemia. A case report.

A 45-year-old man died 2 months after being bitten on the hand by a dog. He developed the rare but characteristic clinical picture of fulminant septicaemia and peripheral gangrene caused by a Gram-negative bacillus, Capnocytophaga canimorsus, previously known as dysgonic fermenter type 2 (DF-2), which is an occasional commensal in the oral flora of dogs and cats. This disease must be anticipated and dog bites appropriately managed to avoid the mortality associated with infection by this micro-organism. Initial treatment includes appropriate prophylactic antibiotics and debridement, while early exchange transfusion and emergency amputation may be of value in fulminant cases.

Microbiological surveillance during selective decontamination of the digestive tract (SDD)

The use of selective decontamination of the digestive tract (SDD) as prophylaxis against nosocomial respiratory tract infection remains controversial, largely because of concerns that, in the long term, it may promote the emergence of antibiotic-resistant strains. This report describes the results of surveillance cultures and susceptibility testing undertaken during the course of a 2-year, double-blind study of the efficacy of SDD which was conducted in a respiratory intensive care unit (ICU). Surveillance specimens from the alimentary tract and trachea were obtained from each patient on admission and then twice weekly until 48 h after discharge from the unit. Specimens were cultured semiquantitatively and organisms from morphologically distinct colonies were identified by standard methods; the susceptibilities of these isolates were determined by the disc diffusion method. Five thousand, nine hundred and sixty surveillance samples from 239 patients were processed in this way. Compared with the placebo group, SDD caused a significant reduction in the incidence of colonization of the alimentary tract with aerobic Gram-negative bacilli (AGNB), and Candida spp. were almost totally eliminated. The incidence of colonization with enterococci increased in both groups, while the incidence of both colonization of the alimentary tract with strains of coagulase-negative staphylococci and methicillin-resistant Staphylococcus aureus and infection caused by these organisms increased in the SDD group. Acinetobacter spp. were the most common bacteria associated with unit-acquired colonization and lower respiratory tract infection in both groups. The acquisition of strains of Pseudomonas aeruginosa and cefotaxime- and/or tobramycin-resistant Enterobacteriaceae was significantly greater in the placebo group than in the SDD group, although tobramycin-resistant strains of Proteus, Morganella and Providencia spp. were isolated from three of 114 patients receiving SDD. The use of SDD did not lead to an overall increase in antibiotic resistance amongst the AGNB usually associated with ICU-acquired infection. However, colonization with strains which were either resistant to one or more of the antibiotic components of the regimen or which were not inhibited by the regimen was observed and may subsequently lead to infection.

Fiberoptic bronchoscopy in the intensive care unit--a prospective study of 147 procedures in 107 patients.

OBJECTIVE: To determine the value and safety of fiberoptic bronchoscopy in an intensive care unit (ICU). DESIGN: Prospective survey. SETTING: ICUs at a tertiary care hospital (except for seven procedures that were performed at a peripheral hospital ICU). PATIENTS: A total of 107 patients with a mean age of 43.9 yrs (range 15 to 84). INTERVENTIONS: One hundred forty-seven fiberoptic bronchoscopy procedures (116 performed on patients who were undergoing mechanical ventilation) were performed on 107 patients. Ninety-four procedures were for diagnostic reasons (upper and lower airway inspection, focal and diffuse pulmonary infiltrates), 37 for therapeutic reasons (bronchial toilet, pulmonary hemorrhage, endotracheal intubation), and 16 for both reasons. Topical anaesthesia was used for fiberoptic bronchoscopy; sedation was rarely needed. Appropriate diagnostic and therapeutic procedures were performed. MEASUREMENTS AND MAIN RESULTS: Oxygen saturation, electrocardiogram, and blood pressure were monitored. Transbronchial biopsies (all on mechanical ventilation) for diffuse pulmonary infiltrates were diagnostic in five of seven cases, and were suggestive of the diagnosis in a further case. Endobronchial biopsies were not diagnostic in any of three cases. Bronchial brushings for microbiology were positive in nine of 50 procedures and for cytology in one of nine procedures. Protected specimen brushes for pulmonary infiltrates gave positive microbiology findings in five of 23 procedures. In pulmonary hemorrhage, focal bleeding was found in five cases, diffuse bleeding in four, and no bleeding source in three. In lobar atelectasis, bronchial toilet led to full reexpansion (n = 20 procedures), partial reexpansion (n = 5), and no change (n = 3). Intubation with fiberoptic bronchoscopy was successful in four of five patients. Hypoxemia (oxygen saturation < 90%) occurred in 29 procedures; it caused no problems. Complications included hemorrhage (n = 2), supraventricular tachycardia (n = 1), pneumothorax (n = 1), pneumatocele (n = 1), and bronchospasm (n = 1). No deaths were attributable to fiberoptic bronchoscopy. CONCLUSIONS: Fiberoptic bronchoscopy in the ICU is safe, contributes valuable diagnostic information, and is useful for therapeutic purposes.

Selective decontamination of the digestive tract in multiple trauma patients--is there a role? Results of a prospective, double-blind, randomized trial.

OBJECTIVE: To evaluate the efficacy of the technique of selective decontamination of the digestive tract in preventing the development of secondary infection and its influence on morbidity and mortality rates in multiple trauma patients with chest injuries requiring intermittent positive-pressure ventilation. DESIGN: Prospective, double-blind, randomized study. SETTING: A multidisciplinary respiratory intensive care unit (ICU) in a 1,500-bed teaching hospital. PATIENTS: Seventy-two patients (mean Injury Severity Score of 29.5) who were intubated for > 48 hrs and remained in the ICU for > 5 days. INTERVENTIONS: Patients were randomized on admission to receive selective decontamination therapy or placebo. All patients received intravenous cefotaxime for 72 hrs and the treatment group received oral and enteral selective decontamination with amphotericin B, polymyxin E, and tobramycin (n = 39), while the placebo group received a placebo containing oral paste and enteral solution (n = 33). MEASUREMENTS: Secondary infection was determined clinically and microbiologically and surveillance cultures were monitored for gastrointestinal colonization. RESULTS: The patient groups were fully comparable for age, severity of illness, and compromising factors. There was no difference in the number of patients infected (11 treatment group vs. 11 placebo), infections (17 vs. 16) and deaths (5 vs. 3); the duration of ICU (15.5 vs. 14.2 days) and hospital stays (26.3 vs. 25.5) were also similar. Microbiological surveillance cultures confirmed effective elimination of aerobic Gram-negative bacilli, and infections in the treatment group were largely due to Staphylococcus aureus and Staphylococcus epidermidis. CONCLUSION: We have been unable to show any benefit from the use of selective decontamination of the digestive tract in the prevention of secondary infections in multiple trauma patients.

Severe pneumococcal pneumonia complicated by massive pulmonary gangrene.

Massive pulmonary gangrene is a rare complication of pneumonia, particularly in the postantibiotic era. We report two cases of community-acquired Streptococcus pneumoniae pneumonia in young patients with a background of heavy alcohol abuse, but no other preexisting disease, which failed to respond to appropriate antibiotic therapy and intensive care. In both, there was extensive unilateral involvement, with initial dense consolidation followed by cavitation, but the previously reported classic later radiologic feature of coalescence into a large cavity with free-floating slough was not seen. Owing to ongoing sepsis with the development of multiple organ failure and the obvious failure of appropriate medical therapy, both patients underwent pneumonectomy with a successful outcome. These cases serve to emphasize the role of surgery in the management of massive pulmonary gangrene.

Neurologic disease requiring long-term ventilation. The role of selective decontamination of the digestive tract in preventing nosocomial infection.

STUDY OBJECTIVE: To evaluate the efficacy of the technique of selective decontamination of the digestive tract (SDD) in preventing secondary infections in patients with neurologic diseases requiring intensive care. DESIGN: Randomized, double-blind, placebo-controlled trial using amphotericin B, polymyxin E, and tobramycin applied to the oropharynx and enterally; all patients received intravenous cefotaxime for 72 h. SETTING: Respiratory ICU. PATIENTS: Forty patients with neurologic diseases requiring ventilation for > 48 h and ICU stay > 5 days. Neurologic diagnosis included acute inflammatory demyelinating neuropathy (15), meningoencephalitis (10), status epilepticus (6), tetanus (6), and myasthenia gravis (3). INTERVENTIONS: Microbiologic surveillance samples of oropharyngeal and tracheal secretions, gastric aspirates, stool, urine, and any other potentially infected sites were taken at the time of ICU admission and twice weekly thereafter until 3 days after discharge from the unit. The SDD was applied every 6 h to the oropharynx and enterally. MEASUREMENTS AND RESULTS: Effective decontamination of the gastrointestinal tract was achieved in the patients receiving the active regimen; however, there was no reduction in the incidence of infections (11 in the active group vs 10 in placebo), and duration of ICU stay (30.1 +/- 22.5 vs 20.6 +/- 17.7 days) and hospital stay (49.3 +/- 31.9 vs 40 +/- 33.4 days) were unaffected as was the mortality (15 percent vs 15 percent). CONCLUSIONS: SDD did not reduce the incidence of secondary infection in patients with neurologic disease, nor did it affect morbidity or mortality; however, it adds considerably to the cost of patient care.

Anaplastic large-cell Ki-1 lymphoma. Pulmonary presentation mimicking miliary tuberculosis.

An unusual presentation of anaplastic large-cell (ALC) Ki-1 lymphoma is described, in which pulmonary involvement mimicked miliary tuberculosis. Lung involvement is uncommon in this type of lymphoma, and it is not clear from previous reports whether this was a presenting feature. Bone marrow involvement, rare in Ki-1 lymphoma, also was present in this case. Despite therapy skin involvement subsequently developed, and the patient died 3 months after presentation. Postmortem examination revealed lymphomatous involvement of the heart, liver, kidneys, stomach, and lymph nodes. This case highlights the need for awareness of ALC Ki-1 lymphoma particularly when it presents at uncommon extranodal sites.