Adherence to Best Practice Advice for Diagnosis of Pulmonary Embolism

PURPOSE

This study evaluated clinician adherence to the American College of Physicians Best Practice Advice for diagnosis of pulmonary embolism.

DESIGN

A prospective, single-center, descriptive design was utilized.

METHODS

A heterogeneous sample of 111 hemodynamically stable adult inpatients with a computed tomography pulmonary angiogram ordered was consented. Electronic medical records were reviewed for demographic and clinical variables to determine adherence. The 6 individual best practice statements and the overall adherence were evaluated by taking the sum of "yes" answers divided by the sample size.

RESULTS

Overall adherence was 0%. Partial adherence was observed with clinician-recorded clinical decisions rules and obtaining d-dimer (3.6% [4/111] and 10.2% [9/88], respectively) of low/intermediate probability scorers. Age adjustment of d-dimer was not recorded. Computed tomography pulmonary angiogram was the first diagnostic test in 89.7% (79/88) in low/intermediate probability patients.

CONCLUSION

In hemodynamically stable, hospitalized adults, adherence to best practice guidelines for diagnosis of pulmonary embolism was minimal. Clinical utility of the guidelines in hospitalized adults needs further evaluation. Systems problems (eg, lack of standardized orders, age-adjusted d-dimer values, information technology support) likely contributed to poor guideline adherence.

Implementation of an Interdisciplinary AACN Early Mobility Protocol

BACKGROUND

Increasing mobility in the intensive care unit is an important part of the ABCDEF bundle. Objective To examine the impact of an interdisciplinary mobility protocol in 7 specialty intensive care units that previously implemented other bundle components.

METHODS

A staggered quality improvement project using the American Association of Critical-Care Nurses mobility protocol was conducted. In phase 1, data were collected on patients with intensive care unit stays of 24 hours or more for 2 months before and 2 months after protocol implementation. In phase 2, data were collected on a random sample of 20% of patients with an intensive care unit stay of 3 days or more for 2 months before and 12 months after protocol implementation.

RESULTS

The study population consisted of 1266 patients before and 1420 patients after implementation in phase 1 and 258 patients before and 1681 patients after implementation in phase 2. In phase 1, the mean (SD) mobility level increased in all intensive care units, from 1.45 (1.03) before to 1.64 (1.03) after implementation (P < .001). Mean (SD) ICU Mobility Scale scores increased on initial evaluation from 4.4 (2.8) to 5.0 (2.8) (P = .01) and at intensive care unit discharge from 6.4 (2.5) to 6.8 (2.3) (P = .04). Complications occurred in 0.2% of patients mobilized. In phase 2, 84% of patients had out-of-bed activity after implementation. The time to achieve mobility levels 2 to 4 decreased (P = .05). Intensive care unit length of stay decreased significantly in both phases.

CONCLUSIONS

Implementing the American Association of Critical-Care early mobility protocol in intensive care units with ABCDEF components in place can increase mobility levels, decrease length of stay, and decrease delirium with minimal complications.

Accuracy of Measuring Bladder Volumes With Ultrasound and Bladder Scanning

BACKGROUND

Removal of urinary catheters depends on accurate noninvasive measurements of bladder volume. Patients with acute kidney injury often have low bladder volumes/ascites, possibly causing measurement inaccuracy.

OBJECTIVE

To evaluate the accuracy of bladder volumes measured with bladder scanning and 2-dimensional ultrasound (US) compared with urinary catheterization among different types of clinicians.

METHODS

Prospective correlational descriptive study of 73 adult critical care patients with low urine output receiving hemodialysis or unable to void. Bladder volumes were independently measured by (1) a physician and an advanced practice registered nurse using US, (2) an advanced practice registered nurse and a bedside nurse using bladder scanning, and (3) urinary catheterization (cath). Bland-Altman and χ2 analyses were conducted.

RESULTS

Mean (SD) cath volume was 171.7 (269.7) mL (range, 0-1100 mL). Abdominal fluid was observed in 28% of patients. Bias was -1.3 mL for US vs cath and 3.3 mL for bladder scanning vs cath. For patients with abdominal fluid and cath volume less than 150 mL, decisions to not catheterize patients were accurate more often when based on US measurements (97%-100%) than when based on bladder scanning measurements (86%-89%; P = .02). In patients with cath volume of 300 mL or more, decisions to catheterize patients were accurate more often when based on bladder scanning measurements (94%-100%) than when based on horizontal US measurements (50%-56%; P = .001).

CONCLUSIONS

Bladder volume can be measured accurately with bladder scanning or US, but abdominal fluid remains a confounding factor limiting accuracy of bladder scanning.

Excluding Pulmonary Embolism with End-tidal Carbon Dioxide: Accuracy, Cost, and Harm Avoidance

A non-randomized single center prospective, descriptive, correlational design was used to determine what end-tidal carbon dioxide (EtCO₂) level provided the best sensitivity, specificity, and negative predictive value to exclude pulmonary embolism (PE) diagnosis in hemodynamically stable hospitalized adults (n = 111). The financial impact and harm avoidance of adding EtCO₂ to the PE diagnostic process also were examined. PE diagnosis was determined by computed tomography pulmonary angiography (CTPA). PE prevalence was 18.9%. Mean±SD EtCO₂ was lower for PE positive than negative participants (28 ± 7.8 to 33 ± 8.1 mmHg respectively 95% CI: 1.22-8.96; P = .01). For PE exclusion, an EtCO₂ cutoff ≥42 mmHg yielded 100% sensitivity, 12.2% specificity, and 100% negative predictive value. For every six inpatients assessed with EtCO₂, one could be saved from unnecessary CTPA. Eliminating unnecessary CTPA removes the potential harm associated with radiation and intravenous contrast exposure. Additionally, an EtCO₂ cutoff ≥42 mmHg could eliminate ~$88,000/year in healthcare waste at this institution.

Leverage points to improve smoking cessation treatment in a large tertiary care hospital: a systems-based mixed methods study

OBJECTIVES

To generate system insights on patient and provider levers and strategies that must be activated to improve hospital-based smoking cessation treatment.

DESIGN

Mixed methods study including a series of in-depth group model building sessions, which informed the design of an online survey completed by healthcare providers and a structured interview protocol administered at the bedside to patients who smoke.

SETTING

Large, tertiary care hospital in the Midwestern United States.

PARTICIPANTS

Group model building: 28 healthcare providers and 22 previously-hospitalised patients; Online survey: 308 healthcare providers; Bedside interviews: 205 hospitalised patients.

PRIMARY AND SECONDARY OUTCOME MEASURES

Hypothesis-generating, participatory qualitative methods informed the examination of the following quantitative outcomes: patient interest versus provider perception of patient interest in smoking cessation and treatment; patient-reported receipt versus provider-reported offering of inpatient smoking cessation interventions; and priority ratings of importance and feasibility of strategies to improve treatment.

RESULTS

System insights included patients frequently leaving the floor to smoke, which created major workflow disruption. Leverage points included interventions to reduce withdrawal symptoms, and action ideas included nurse-driven protocols for timely administration of nicotine replacement therapy. Quantitative data corroborated system insights; for instance, 80% of providers reported that patients frequently leave the floor to smoke, leading to safety risks, missed assessments and inefficient use of staff time. Patients reported significantly lower rates of receiving any smoking cessation interventions, compared with provider reports (mean difference=17.4%-33.7%, p<0.001). Although 92% of providers cited patient interest as a key barrier, only 4% of patients indicated no interest in quitting or reducing smoking.

CONCLUSIONS

Engaging hospital providers and patients in participatory approaches to develop an implementation strategy revealed discrepant perceptions of patient interest and frequency of hospital-based treatment for smoking. These findings spurred adoption of standardised point-of-care treatment for cigarette smoking, which remains highly prevalent yet undertreated among hospitalised patients.

Diagnosis of pulmonary embolism: Following the evidence from suspicion to certainty

Accurate, timely and cost-effective identification of pulmonary embolism remains a diagnostic challenge. This article reviews the pulmonary embolism diagnostic process with a focus on the best practice advice from the American College of Physicians. Benefits and risks of each diagnostic step are discussed. Emerging diagnostic tools, not included in the algorithm, are briefly reviewed.

Comparison of nasal and forehead oximetry accuracy and pressure injury in critically ill patients

BACKGROUND

In critically ill patients, clinicians can have difficulty obtaining accurate oximetry measurements.

OBJECTIVE

To compare the accuracy of nasal alar and forehead sensor measurements and incidence of pressure injury.

METHODS

43 patients had forehead and nasal alar sensors applied. Arterial samples were obtained at 0, 24, and 120 hours. Oxygen saturations measured by co-oximetry were compared to sensor values. Skin was assessed every 8 hours.

RESULTS

Oxygen saturations ranged from 69.8%-97.8%, with 18% of measures < 90%. Measurements were within 3% of co-oximetry values for 54% of nasal alar compared to 35% of forehead measurements. Measurement failures occurred in 6% for nasal alar and 22% for forehead. Three patients developed a pressure injury with the nasal alar sensor and 13 patients developed a pressure injury with the forehead sensor (χ2 = 7.68; p = .006).

CONCLUSIONS

In this group of patients with decreased perfusion, nasal alar sensors provided a potential alternative for continuous monitoring of oxygen saturation.

Chlorhexidine gluconate bathing to reduce methicillin-resistant Staphylococcus aureus acquisition

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is a virulent organism causing substantial morbidity and mortality in intensive care units. Chlorhexidine gluconate, a topical antiseptic solution, is effective against a wide spectrum of gram-positive and gram-negative bacteria, including MRSA. Objectives To examine the impact of a bathing protocol using chlorhexidine gluconate and bath basin management on MRSA acquisition in 5 adult intensive care units and to examine the cost differences between chlorhexidine bathing by using the bath-basin method versus using prepackaged chlorhexidine-impregnated washcloths.

METHODS

The protocol used a 4-oz bottle of 4% chlorhexidine gluconate soap in a bath basin of warm water. Patients in 3 intensive care units underwent active surveillance for MRSA acquisition; patients in 2 other units were monitored for a new positive culture for MRSA at any site 48 hours after admission.

RESULTS

Before the protocol, 132 patients acquired MRSA in 34333 patient days (rate ratio, 3.84). Afterwards, 109 patients acquired MRSA in 41376 patient days (rate ratio, 2.63). The rate ratio difference is 1.46 (95% CI, 1.12-1.90; P = .003). The chlorhexidine soap and bath basin method cost $3.18 as compared with $5.52 for chlorhexidine-impregnated wipes (74% higher).

CONCLUSIONS

The chlorhexidine bathing protocol is easy to implement, cost-effective, and led to decreased unit-acquired MRSA rates in a variety of adult intensive care units.

A usability evaluation exploring the design of American Nurses Association state web sites

National leaders are calling for opportunities to facilitate the Future of Nursing. Opportunities can be encouraged through state nurses association Web sites, which are part of the American Nurses Association, that are well designed, with appropriate content, and in a language professional nurses understand. The American Nurses Association and constituent state nurses associations provide information about nursing practice, ethics, credentialing, and health on Web sites. We conducted usability evaluations to determine compliance with heuristic and ethical principles for Web site design. We purposefully sampled 27 nursing association Web sites and used 68 heuristic and ethical criteria to perform systematic usability assessments of nurse association Web sites. Web site analysis included seven double experts who were all RNs trained in usability analysis. The extent to which heuristic and ethical criteria were met ranged widely from one state that met 0% of the criteria for "help and documentation" to states that met greater than 92% of criteria for "visibility of system status" and "aesthetic and minimalist design." Suggested improvements are simple yet make an impact on a first-time visitor's impression of the Web site. For example, adding internal navigation and tracking features and providing more details about the application process through help and frequently asked question documentation would facilitate better use. Improved usability will improve effectiveness, efficiency, and consumer satisfaction with these Web sites.

Successful treatment of macrophage activation syndrome complicating adult Still disease with anakinra

A previously healthy 20-year-old man presented with adult Still disease (ASD). He developed life-threatening macrophage activation syndrome (MAS), which was refractory to standard immunosuppression but responded dramatically to the IL-1 receptor antagonist anakinra. Subsequent immunological investigations included assessment of the perforin expression of natural killer (NK) cells and CD8+ T cells, which confirmed MAS.

National survey of central venous catheter flushing in the intensive care unit

BACKGROUND

Evidence is needed on the best solution for flushing central venous catheters.

OBJECTIVE

To understand current flushing practices for short-term central venous catheters among critical care nurses before implementation of a randomized, controlled trial comparing physiological saline with heparin solution for flushing to maintain catheter patency.

METHODS

A 6-item survey including demographic data was mailed to 2000 practicing critical care nurses in the United States. An additional 316 surveys were completed at the annual conference of the American Association of Critical-Care Nurses.

RESULTS

Most (71.5%) of the 632 respondents who completed the survey were staff nurses. Most respondents (64.6%; 95% CI, 60.86%-68.34%) reported using physiological saline exclusively to flush central venous catheters and maintain patency. For heparin-containing solutions, the concentration and volume used varied. The most commonly reported volumes for flushing were 10 mL for saline (63%; 95% CI, 59.18%-66.82%) and 3 mL for heparin (50.2%; 95% CI, 43.5%-56.9%).

CONCLUSION

Flushing practices for central venous catheters vary widely. A randomized controlled trial is needed to determine the optimal flushing solution to maintain short-term patency.

Before–after study of a standardized hospital order set for the management of septic shock*

OBJECTIVE

To evaluate a standardized hospital order set for the management of septic shock in the emergency department.

DESIGN

Before-after study design with prospective consecutive data collection.

SETTING

Emergency department of a 1,200-bed academic medical center.

PATIENTS

A total of 120 patients with septic shock.

INTERVENTIONS

Implementation of a standardized hospital order set for the management of septic shock.

MEASUREMENTS AND MAIN RESULTS

A total of 120 consecutive patients with septic shock were identified. Sixty patients (50.0%) were managed before the implementation of the standardized order set, constituting the before group, and 60 (50.0%) were evaluated after the implementation of the standardized order set, making up the after group. Demographic variables and severity of illness measured by the Acute Physiology and Chronic Health Evaluation II were similar for both groups. Patients in the after group received statistically more intravenous fluids while in the emergency department (2825 +/- 1624 mL vs. 3789 +/- 1730 mL, p = .002), were more likely to receive intravenous fluids of >20 mL/kg body weight before vasopressor administration (58.3% vs. 88.3%, p < .001), and were more likely to be treated with an appropriate initial antimicrobial regimen (71.7% vs. 86.7%, p = .043) compared with patients in the before group. Patients in the after group were less likely to require vasopressor administration at the time of transfer to the intensive care unit (100.0% vs. 71.7%, p < .001), had a shorter hospital length of stay (12.1 +/- 9.2 days vs. 8.9 +/- 7.2 days, p = .038), and a lower risk for 28-day mortality (48.3% vs. 30.0%, p = .040).

CONCLUSIONS

Our study found that the implementation of a standardized order set for the management of septic shock in the emergency department was associated with statistically more rigorous fluid resuscitation of patients, greater administration of appropriate initial antibiotic treatment, and a lower 28-day mortality. These data suggest that the use of standardized order sets for the management of septic shock should be routinely employed.

Esophageal Doppler monitoring for hemodynamic assessment

This article reviews the importance of hemodynamic monitoring in adding to the clinical assessment of critically ill patients. The esophageal Doppler monitor (EDM) provides a less invasive way of obtaining hemodynamic information quickly and safely at the bedside. The concepts of Doppler signal acquisition and important nursing considerations are reviewed. Case studies are provided to understand how data from the EDM can impact patient care decisions at the bedside.

Short communication: Efficacy of parenteral ceftiofur for treatment of systemically mild clinical mastitis in dairy cattle

The objective of this study was to evaluate the effect of intramuscular (i.m.) ceftiofur (2.2 mg/kg) on important outcomes of systemically mild clinical mastitis episodes in lactating dairy cattle. Cows with clinical mastitis were randomly assigned to a treatment group: pirlimycin intramammary (i.m.m.) (n = 35), pirlimycin i.m.m. and ceftiofur i.m.m. (n = 36), cephapirin i.m.m. (n = 40), cephapirin i.m. and ceftiofur i.m. (n = 33). Sixty-nine, 22, and 9% of initial cultures were gram-negative, gram-positive, and mixed, respectively. Logistic regression analysis showed no significant associations between treatment groups and loss of quarter, recurrence, or culling. Mixed infections, positive milk culture at 7 d after leaving hospital pen, decreased rumen motility, and absence of udder firmness were associated with increased odds of mastitis recurrence. The results suggest that i.m. ceftiofur treatment has no beneficial effects on the outcome of systemically mild clinical mastitis.

The Effect of an Education Program on the Incidence of Central Venous Catheter-Associated Bloodstream Infection in a Medical ICU

OBJECTIVE

To determine whether an education initiative could decrease the rate of catheter-associated bloodstream infection.

DESIGN

Preintervention and postintervention observational study.

SETTING

The 19-bed medical ICU in a 1,400-bed university-affiliated urban teaching hospital.

PATIENTS

Between January 2000 and December 2003, all patients admitted to the medical ICU were surveyed prospectively for the development of catheter-associated bloodstream infection.

INTERVENTION

A mandatory education program directed toward ICU nurses and physicians was developed by a multidisciplinary task force to highlight correct practices for the prevention of catheter-associated bloodstream infection. The program consisted of a 10-page self-study module on risk factors and practice modifications involved in catheter-related bloodstream infections and in-services at scheduled staff meetings. Each participant was required to complete a pretest before reviewing the study module and an identical test after completion of the study module. Fact sheets and posters reinforcing the information in the study module were also posted throughout the ICU.

MEASUREMENTS AND MAIN RESULTS

Seventy-four episodes of catheter-associated bloodstream infection occurred in 7,879 catheter-days (9.4 per 1,000 catheter-days) in the 24 months before the introduction of the education program. Following implementation of the intervention, the rate of catheter-associated bloodstream infection decreased to 41 episodes in 7,455 catheter days (5.5 per 1,000 catheter-days) [p = 0.019]. The estimated cost savings secondary to the decreased rate of catheter-associated bloodstream infection for the 24 months following introduction of the education program was between $103,600 and $1,573,000.

CONCLUSIONS

An intervention focused on the education of health-care providers on the prevention of catheter-associated bloodstream infections may lead to a dramatic decrease in the incidence of primary bloodstream infections. Education programs may lead to a substantial decrease in medical-care costs and patient morbidity attributed to central venous catheterization when implemented as part of mandatory training.

Reporting of medical errors: An intensive care unit experience

OBJECTIVE

To determine the occurrence and type of medical errors in an intensive care setting using a voluntary reporting method.

DESIGN

Prospective, single-center, observational study.

SETTING

The medical intensive care unit (19 beds) at an urban teaching hospital.

PATIENTS

Adult patients requiring at least 48 hrs of intensive care.

INTERVENTIONS

Prospective reporting of medical errors.

MEASUREMENTS AND MAIN RESULTS

During a 6-month period, 232 medical events were reported involving 147 patients. A total of 2598 patient days were surveyed yielding 89.3 medical events reported per 1000 intensive care unit days. The source of the reports included nurses, who reported most of the medical events (59.1%), followed by physicians-in-training (27.2%) and intensive care unit attending physicians (2.6%). One hundred thirty (56.2%) medical events occurred within the intensive care unit and were judged to involve patient careproviders who were working directly in the intensive care unit area. One hundred and two (43.8%) medical events were commissions or omissions that occurred outside of the intensive care unit during patient transports or in the emergency department and hospital floors. Twenty-three (9.9%) medical events leading to a medical error resulted in the need for additional life-sustaining treatment, and seven (3.0%) medical errors may have contributed to patient deaths.

CONCLUSION

Medical errors appear to be common among patients requiring intensive care. Medical events resulting in an error can result in the need for additional life-sustaining treatments and, in some circumstances, can contribute to patient death. Patient healthcare providers appear to be in a unique position to identify medical errors. Institutions should develop formalized methods for the reporting and analysis of medical errors to improve patient care.

Physicians' estimates of cardiac index and intravascular volume based on clinical assessment versus transesophageal Doppler measurements obtained by critical care nurses

OBJECTIVES

To compare physicians' estimates of cardiac index and intravascular volume with transesophageal Doppler measurements obtained by critical care nurses, to assess the overall safety of transesophageal Doppler imaging by critical care nurses, and to compare hemodynamic measurements obtained via transesophageal Doppler imaging with those obtained via pulmonary artery catheterization.

METHODS

Data were collected prospectively on 106 patients receiving mechanical ventilation. Physicians estimated cardiac index and intravascular volume status by using bedside clinical assessment; critical care nurses, by using transesophageal Doppler imaging. In 24 patients, Doppler measurements were obtained within 6 hours of placement of a pulmonary artery catheter and recording of cardiac output and pulmonary artery occlusion pressure.

RESULTS

With Doppler measurements as the reference, physicians correctly estimated cardiac index in 46 (43.8%) of 105 patients, underestimated it in 24 (22.9%), and overestimated it in 35 (33.3%). They correctly estimated volume status in 31 patients (29.5%), underestimated it in 16 (15.2%), and overestimated it in 58 (55.2%). Doppler measurements of cardiac output correlated with those obtained via pulmonary artery catheterization (r = 0.778; P < .001). Two patients had minor complications: dislodgement of a nasogastric tube and inability to obtain a Doppler signal.

CONCLUSION

Physicians' assessment of cardiac index and intravascular volume in patients receiving mechanical ventilation is correct less than half of the time. Transesophageal Doppler imaging by critical care nurses appears to be a safe method for measuring cardiac index and estimating intravascular volume. Measurements obtained via Doppler imaging correlate well with those obtained via pulmonary artery catheterization.

Physicians’ Estimates of Cardiac Index and Intravascular Volume Based on Clinical Assessment Versus Transesophageal Doppler Measurements Obtained by Critical Care Nurses

• Objectives To compare physicians’ estimates of cardiac index and intravascular volume with transesophageal Doppler measurements obtained by critical care nurses, to assess the overall safety of transesophageal Doppler imaging by critical care nurses, and to compare hemodynamic measurements obtained via transesophageal Doppler imaging with those obtained via pulmonary artery catheterization.

• Methods Data were collected prospectively on 106 patients receiving mechanical ventilation. Physicians estimated cardiac index and intravascular volume status by using bedside clinical assessment; critical care nurses, by using transesophageal Doppler imaging. In 24 patients, Doppler measurements were obtained within 6 hours of placement of a pulmonary artery catheter and recording of cardiac output and pulmonary artery occlusion pressure.

• Results With Doppler measurements as the reference, physicians correctly estimated cardiac index in 46 (43.8%) of 105 patients, underestimated it in 24 (22.9%), and overestimated it in 35 (33.3%). They correctly estimated volume status in 31 patients (29.5%), underestimated it in 16 (15.2%), and overestimated it in 58 (55.2%). Doppler measurements of cardiac output correlated with those obtained via pulmonary artery catheterization (r = 0.778; P &lt; .001). Two patients had minor complications: dislodgement of a nasogastric tube and inability to obtain a Doppler signal.

• Conclusion Physicians’ assessment of cardiac index and intravascular volume in patients receiving mechanical ventilation is correct less than half of the time. Transesophageal Doppler imaging by critical care nurses appears to be a safe method for measuring cardiac index and estimating intravascular volume. Measurements obtained via Doppler imaging correlate well with those obtained via pulmonary artery catheterization.

Ambulatory care-sensitive conditions: clinical outcomes and impact on intensive care unit resource use

BACKGROUND

We identified risk factors and clinical outcomes associated with ambulatory care-sensitive conditions requiring intensive care unit (ICU) admission.

METHODS

This prospective cohort study included 4,144 patients admitted to the medical ICU of an urban teaching hospital during a 3-year period.

RESULTS

A total of 627 patients were classified as having ambulatory care-sensitive conditions (ie, potentially preventable ICU admissions). Black race, decreasing Acute Physiology and Chronic Health Evaluation II (APACHE II) score, younger age, female sex, and absence of immunodeficiency were independently associated with ambulatory care-sensitive conditions. Patients classified as having ambulatory care-sensitive conditions accounted for 2,006 ventilator days, 2,508 ICU days, and 5,392 hospital days. The hospital mortality rate was statistically lower for patients with ambulatory care-sensitive conditions than for patients without these conditions. Patients classified as having ambulatory care-sensitive conditions were also statistically more likely than other patients to lack health insurance and to sign out of the hospital against medical advice.

CONCLUSION

Patients with ambulatory care-sensitive conditions account for a substantial portion of all admissions to the intensive care unit. These data suggest that interventions aimed at preventing such admissions could improve ICU bed use.

Early versus late enteral feeding of mechanically ventilated patients: results of a clinical trial

BACKGROUND

This study sought to compare 2 strategies for the administration of enteral feeding to mechanically ventilated medical patients.

METHODS

The prospective, controlled, clinical trial was carried out in a medical intensive care unit (19 beds) in a university-affiliated, urban teaching hospital. Between May 1999 and December 2000, 150 patients were enrolled. Patients were scheduled to receive their estimated total daily enteral nutritional requirements on either day 1 (early-feeding group) or day 5 (late-feeding group) of mechanical ventilation. Patients in the late-feeding group were also scheduled to receive 20% of their estimated daily enteral nutritional requirements during the first 4 days of mechanical ventilation.

RESULTS

Seventy-five (50%) consecutive eligible patients were entered into the early-feeding group and 75 (50%) patients were enrolled in the late-feeding group. During the 5 five days of mechanical ventilation, the total intake of calories (2370 +/- 2000 kcal versus 629 +/- 575 kcal; p < .001) and protein (93.6 +/- 77.2 g versus 26.7 +/- 26.6 g; p < .001) were statistically greater for patients in the early-feeding group. Patients in the early-feeding group had statistically greater incidences of ventilator-associated pneumonia (49.3% versus 30.7%; p = .020) and diarrhea associated with Clostridium difficile infection (13.3% versus 4.0%; p = .042). The early-feeding group also had statistically longer intensive care unit (13.6 +/- 14.2 days versus 9.8 +/- 7.4 days; p = .043) and hospital lengths of stay (22.9 +/- 19.7 days versus 16.7 +/- 12.5 days; p = .023) compared with patients in the late-feeding group. No statistical difference in hospital mortality was observed between patients in the early-feeding and late-feeding groups (20.0% versus 26.7%; p = .334).

CONCLUSIONS

The administration of more aggressive early enteral nutrition to mechanically ventilated medical patients is associated with greater infectious complications and prolonged lengths of stay in the hospital. Clinicians must balance the potential for complications resulting from early enteral feeding with the expected benefits of such therapy.

Deep vein thrombosis during prolonged mechanical ventilation despite prophylaxis

OBJECTIVE

To determine the prevalence of deep vein thrombosis (DVT) among patients requiring prolonged mechanical ventilation in the intensive care unit.

DESIGN

Prospective cohort study.

SETTING

Medical intensive care unit of a university-affiliated urban teaching hospital.

PATIENTS

Patients requiring mechanical ventilation for >7 days.

INTERVENTIONS

All patients admitted to the medical intensive care unit requiring prolonged mechanical ventilation underwent duplex ultrasonography of their lower extremities and upper extremities every 7 days. The main outcome identified was the presence of DVT. Secondary outcomes included hospital mortality, hospital and intensive care unit lengths of stay, and the occurrence of pulmonary embolism.

MEASUREMENTS AND MAIN RESULTS

A total of 110 patients requiring mechanical ventilation for >7 days were enrolled. Prophylaxis against DVT was employed in 110 of the patients (100%). A total of 26 patients (23.6%) developed DVT. Patients with DVT were statistically more likely to have underlying malignancy (30.8% vs. 8.3%; p =.004) and longer durations of central venous catheterization (26.9 +/- 22.2 days vs. 14.5 +/- 12.1 days; p =.024) compared with patients without DVT. There were no statistically significant differences in hospital mortality or lengths of stay in the hospital and intensive care unit for patients with and without DVT. Patients documented to have DVT by using duplex ultrasonography had a statistically greater frequency of subsequent pulmonary embolism during their hospitalization (11.5% vs. 0.0%; p =.012).

CONCLUSION

The occurrence of DVT is common among patients requiring prolonged mechanical ventilation in the intensive care unit setting despite the use of prophylaxis measures. These data suggest that alternative strategies for the prevention of DVT should be evaluated. Additionally, early detection methods should be considered to reduce the potential morbidity associated with untreated DVT in this high-risk population.

Migraine and hypertension. Is there a relationship?

BACKGROUND Migraine and hypertension are common conditions that frequently coexist. The relastionship between the two is usually coincidental, but some evidence suggests that poor control of blood pressure may exacerbate the frequency and severity of migraine. OBJECTIVE To review the relationship between migraine, other headaches and blood pressure and to discuss guidelines for suitable therapy for both conditions when they occur together. DISCUSSION Establishing the blood pressure should be a routine task in the assessment of all headache patients. Severe hypertension in the setting of new acute headache may indicate a serious underlying cause and requires urgent investigation. In patients with migraine and established hypertension, good control of blood pressure may be beneficial in controlling their headache. Many of the drugs used to treat hypertension may cause headache and some agents used to treat migraine can exacerbate hypertension and so careful consideration of the therapeutic options is important.

Relaxation of mouse isolated aorta to adenosine and its analogues does not involve adenosine A(1), A(2) or A(3) receptors

Relaxations to adenosine and analogues were investigated in the mouse aorta in the presence of the adenosine A(1) receptor-selective antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 30 nM), which did not affect relaxations to adenosine or its analogue N(6)-R-phenylisopropyladenosine (R-PIA) but abolished contractile adenosine A(1) receptor-mediated responses to these agonists. Relaxations to adenosine, 5'-N-ethylcarboxamidoadenosine, R-PIA, 2-[p-(2-carbonylethyl)-phenylethylamino]-5'-N-ethylcarboxamidoadenosine (CGS 21680), and N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) were unaffected by the adenosine A(1)/A(2) receptor antagonist 8-sulphophenyltheophylline (100 microM). IB-MECA relaxations were unaffected by the adenosine A(3) receptor-selective antagonist 3-ethyl-5-benzyl-2-methyl-6-phenyl-4-phenylethynyl-1,4-(+/-)-dihydropyridine-3,5-dicarboxylate (MRS1191, 30 microM) and R-PIA relaxations were unaffected by N(G)-nitro-L-arginine methyl ester (100 microM) and endothelium removal. In conclusion, relaxant responses to adenosine and analogues do not involve adenosine A(1), A(2) or A(3) receptors and are endothelium- and nitric oxide-independent.

Controversies in the use of the pulmonary artery catheter

The pulmonary artery catheter (PAC) has been in use for more than 30 years. The amount and detail of hemodynamic information provided by the PAC cannot be matched by any other single technology. Whether or not this information makes a difference in the clinical outcomes of critically ill patients is uncertain, however. The Pulmonary Artery Catheter Consensus Conference scrutinized the available research data on the catheter and provided guidelines for clinicians on its use. This article summarizes the controversy and the guidelines available for use of the PAC. It notes the need for further research on patient outcomes.

Inadequate treatment of nosocomial infections is associated with certain empiric antibiotic choices

OBJECTIVE

The purpose of this study was to determine the impact of scheduled changes of antibiotic classes, used for the empirical treatment of suspected or documented Gram-negative bacterial infections, on the occurrence of inadequate antimicrobial treatment of nosocomial infections.

DESIGN

Prospective observational study.

SETTING

Medical (19-bed) and surgical (18-bed) intensive care units in an urban teaching hospital.

PATIENTS

A total of 3,668 patients requiring intensive care unit admission were prospectively evaluated during three consecutive time periods.

INTERVENTIONS

During each time period, one antibiotic class was selected for the empirical treatment of Gram-negative bacterial infections as follows: time period 1 (baseline period) (1,323 patients), ceftazidime; time period 2 (1,243 patients), ciprofloxacin; and time period 3 (1,102 patients), cefepime.

MEASUREMENTS AND MAIN RESULTS

The overall administration of inadequate antimicrobial treatment for nosocomial infections decreased during the course of the study (6.1%, 4.7%, and 4.5%; p = .15). This was primarily because of a statistically significant decrease in the administration of inadequate antibiotic treatment for Gram-negative bacterial infections (4.4%, 2.1%, and 1.6%; p < .001). There were no statistically significant differences in the overall hospital mortality rate among the three time periods (15.6%, 16.4%, and 16.2%; p = .828) despite a significant increase in severity of illness as measured with Acute Physiology and Chronic Health Evaluation (APACHE) II scores (15.3 +/- 7.6, 15.7 +/- 8.0, and 20.7 +/- 8.6; p < .001). The hospital mortality rate decreased significantly during time period 3 (20.6%) compared with time period 1 (28.4%; p < .001) and time period 2 (29.5%; p < .001) for patients with an APACHE II score > or = 15.

CONCLUSIONS

These data suggest that scheduled changes of antibiotic classes for the empirical treatment of Gram-negative bacterial infections can reduce the occurrence of inadequate antibiotic treatment for nosocomial infections. Reducing inadequate antibiotic administration may improve the outcomes of critically ill patients with APACHE II scores > or = 15.

A school and community outbreak of tuberculosis in Auckland

AIM

To describe a school and community outbreak of tuberculosis in South Auckland in 1997/8.

METHODS

Cases were diagnosed according to national guidelines at Middlemore, Green Lane and Starship Hospitals. Public health follow-up was conducted by Auckland Healthcare.

RESULTS

Twelve cases were diagnosed during the outbreak. Nine cases were from the same South Auckland secondary school; six reported no association outside school. Three cases were in younger children who had close household contact with two of the school cases. Nine cases (including eight from the school) had identical Mycobacterium tuberculosis isolates on restriction fragment length polymorphism testing. No microbiological culture was obtained from the three remaining cases. Contact investigation detected five of the cases. Chemoprophylaxis was prescribed for twenty-six school students, two adult staff, and nine household contacts.

CONCLUSION

This is the first published account of a tuberculosis outbreak in a New Zealand school setting for decades. Recognition of the outbreak was delayed. DNA fingerprinting played a valuable role in the investigation. The source case may have been a school student. The social impact of the outbreak and preventability with routine adolescent BCG vaccination are discussed.

Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation

OBJECTIVE

To compare a practice of protocol-directed sedation during mechanical ventilation implemented by nurses with traditional non-protocol-directed sedation administration.

DESIGN

Randomized, controlled clinical trial.

SETTING

Medical intensive care unit (19 beds) in an urban teaching hospital.

PATIENTS

Patients requiring mechanical ventilation (n = 321).

INTERVENTIONS

Patients were randomly assigned to receive either protocol-directed sedation (n = 162) or non-protocol-directed sedation (n = 159).

MEASUREMENTS AND MAIN RESULTS

The median duration of mechanical ventilation was 55.9 hrs (95% confidence interval, 41.0-90.0 hrs) for patients managed with protocol-directed sedation and 117.0 hrs (95% confidence interval, 96.0-155.6 hrs) for patients receiving non-protocol-directed sedation. Kaplan-Meier analysis demonstrated that patients in the protocol-directed sedation group had statistically shorter durations of mechanical ventilation than patients in the non-protocol-directed sedation group (chi-square = 7.00, p = .008, log rank test; chi-square = 8.54, p = .004, Wilcoxon's test; chi-square = 9.18, p = .003, -2 log test). Lengths of stay in the intensive care unit (5.7+/-5.9 days vs. 7.5+/-6.5 days; p = .013) and hospital (14.0+/-17.3 days vs. 19.9+/-24.2 days; p < .001) were also significantly shorter among patients in the protocol-directed sedation group. Among the 132 patients (41.1%) receiving continuous intravenous sedation, those in the protocol-directed sedation group (n = 66) had a significantly shorter duration of continuous intravenous sedation than those in the non-protocol-directed sedation group (n = 66) (3.5+/-4.0 days vs. 5.6+/-6.4 days; p = .003). Patients in the protocol-directed sedation group also had a significantly lower tracheostomy rate compared with patients in the non-protocol-directed sedation group (10 of 162 patients [6.2%] vs. 21 of 159 patients [13.2%], p = .038).

CONCLUSIONS

The use of protocol-directed sedation can reduce the duration of mechanical ventilation, the intensive care unit and hospital lengths of stay, and the need for tracheostomy among critically ill patients with acute respiratory failure.

A comparison of infrared ear thermometry with electronic predictive thermometry in a geriatric setting

This project had three purposes: to determine the test/retest reliability of three thermometers--an infrared ear thermometer, an oral electronic predictive thermometer, and an oral mercury-in-glass thermometer (MIGT); determine the validity (accuracy) of the first two thermometers using the MIGT as the gold standard; and calculate the thermometers' sensitivity and specificity for detecting fever using 37.5 degrees C on the MIGT as the criterion. The MIGT had the best reliability, followed by the electronic predictive and infrared ear thermometer (for validity, the former was more accurate than the latter). Little difference existed in the latter two thermometers' sensitivity and specificity. However, the confidence intervals were wide, and further studies with larger samples need to be done to elucidate the thermometers' diagnostic properties.

A decentralized admission screening protocol for a geriatric rehabilitation program: does it make a difference?

The purpose of this retrospective evaluation study was to compare outcomes related to two distinct processes for screening people referred for admission to a geriatric rehabilitation program at a chronic care hospital in southern Ontario. Data were collected through chart review and focus group methods. The results were unexpected in that the projected outcomes associated with the newer referral screening process did not materialize. For both referral screening processes, findings are discussed in terms of the percentage of achieved patient rehabilitation goals. The average lengths of patient stay associated with both screening processes were also compared. No statistically significant differences between the two processes were found in terms of either the percentage of goals achieved or the length of patient stay. Focus group sessions were held to elicit team members' perceptions of the effectiveness of each of the referral processes. Participants in the focus groups were supportive of the newer referral screening and admission process although the evidence gathered from the chart review did not demonstrate improvements in patients' length of stay or an increase in the percentage of rehabilitation goals achieved.

The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation

STUDY OBJECTIVE

To determine whether the use of continuous i.v. sedation is associated with prolongation of the duration of mechanical ventilation.

DESIGN

Prospective observational cohort study.

SETTING

The medical ICU of Barnes-Jewish Hospital, a university-affiliated urban teaching hospital.

PATIENTS

Two hundred forty-two consecutive ICU patients requiring mechanical ventilation.

INTERVENTIONS

Patient surveillance and data collection.

MEASUREMENTS AND RESULTS

The primary outcome measure was the duration of mechanical ventilation. Secondary outcome measures included ICU and hospital lengths of stay, hospital mortality, and acquired organ system derangements. A total of 93 (38.4%) mechanically ventilated patients received continuous i.v. sedation while 149 (61.6%) patients received either bolus administration of i.v. sedation (n=64) or no i.v. sedation (n=85) following intubation. The duration of mechanical ventilation was significantly longer for patients receiving continuous i.v. sedation compared with patients not receiving continuous i.v. sedation (185+/-190 h vs 55.6+/-75.6 h; p<0.001). Similarly, the lengths of intensive care (13.5+/-33.7 days vs 4.8+/-4.1 days; p<0.001) and hospitalization (21.0+/-25.1 days vs 12.8+/-14.1 days; p<0.001) were statistically longer among patients receiving continuous i.v. sedation. Multiple linear regression analysis, adjusting for age, gender, severity of illness, mortality, indication for mechanical ventilation, use of chemical paralysis, presence of a tracheostomy, and the number of acquired organ system derangements, found the adjusted duration of mechanical ventilation to be significantly longer for patients receiving continuous i.v. sedation compared with patients who did not receive continuous i.v. sedation (148 h [95% confidence interval: 121, 175 h] vs 78.7 h [95% confidence interval: 68.9, 88.6 h]; p<0.001).

CONCLUSION

We conclude from these preliminary observational data that the use of continuous i.v. sedation may be associated with the prolongation of mechanical ventilation. This study suggests that strategies targeted at reducing the use of continuous i.v. sedation could shorten the duration of mechanical ventilation for some patients. Prospective randomized clinical trials, using well-designed sedation guidelines and protocols, are required to determine whether patient-specific outcomes (eg, duration of mechanical ventilation, patient comfort) can be improved compared with conventional sedation practices.

A randomized clinical trial comparing an extended-use hygroscopic condenser humidifier with heated-water humidification in mechanically ventilated patients

STUDY OBJECTIVE

To determine the safety and cost-effectiveness of mechanical ventilation with an extended-use hygroscopic condenser humidifier (Duration; Nellcor Puritan-Bennett; Eden Prairie, Minn) compared with mechanical ventilation with heated-water humidification.

DESIGN

Prospective randomized clinical trial.

SETTING

Medical and surgical ICUs of Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital.

PATIENTS

Three hundred ten consecutive qualified patients undergoing mechanical ventilation.

INTERVENTIONS

Patients requiring mechanical ventilation were randomly assigned to receive humidification with either an extended-use hygroscopic condenser humidifier (for up to the first 7 days of mechanical ventilation) or heated-water humidification.

MEASUREMENTS

Occurrence of ventilator-associated pneumonia, endotracheal tube occlusion, duration of mechanical ventilation, lengths of intensive care and hospitalization, acquired multiorgan dysfunction, and hospital mortality.

RESULTS

One hundred sixty-three patients were randomly assigned to receive humidification with an extended-use hygroscopic condenser humidifier, and 147 patients were randomly assigned to receive heated-water humidification. The two groups were similar at the time of randomization with regard to demographic characteristics, ICU admission diagnoses, and severity of illness. Risk factors for the development of ventilator-associated pneumonia were also similar during the study period for both treatment groups. Ventilator-associated pneumonia was seen in 15 (9.2%) patients receiving humidification with an extended-use hygroscopic condenser humidifier and in 15 (10.2%) patients receiving heated-water humidification (relative risk, 0.90; 95% confidence interval=0.46 to 1.78; p=0.766). No statistically significant differences for hospital mortality, duration of mechanical ventilation, lengths of stay in the hospital ICU, or acquired organ system derangements were found between the two treatment groups. No episode of endotracheal tube occlusion occurred during the study period in either treatment group. The total cost of providing humidification was $2,605 for patients receiving a hygroscopic condenser humidifier compared with $5,625 for patients receiving heated-water humidification.

CONCLUSION

Our findings suggest that the initial application of an extended-use hygroscopic condenser humidifier is a safe and more cost-effective method of providing humidification to patients requiring mechanical ventilation compared with heated-water humidification.

Sequential increases in the intrahepatic expression of epidermal growth factor, basic fibroblast growth factor, and transforming growth factor beta in a bile duct ligated rat model of cirrhosis

Chronic hepatic regeneration constitutes an important part of the cirrhotic process. The factors regulating chronic hepatic regeneration, however, remain unclear. We therefore analyzed the intrahepatic messenger RNA (mRNA) expression of growth factors (epidermal growth factor [EGF], basic fibroblast growth factor [bFGF], hepatocyte growth factor [HGF], transforming growth factor [TGF]-alpha, and TGF-beta) at progressive time points (postoperative days 2, 7, 14, and 21) in a rat bile duct-ligated (BDL) model of cirrhosis versus sham controls. Intrahepatic growth factor mRNA expression was quantitatively assessed by polymerase chain reaction (PCR) using a dot-blot hybridization technique. Cirrhosis was associated with statistically significant (P < .05) progressive increases in the intrahepatic mRNA expression of bFGF (80-fold), EGF (25-fold), and TGF-beta (fourfold) in BDL animals versus controls. Furthermore, immunohistochemistry of hepatic sections showed a progressive up-regulation of bFGF protein in areas of bile duct proliferation. These areas also showed a dramatic increase in the number of hepatic stellate cells (HSC). In contrast, the intrahepatic expression of hepatocyte growth factor (HGF) mRNA was only significantly increased at postoperative days 7 and 14 in BDL animals before returning to control levels as cirrhosis developed. There were no significant differences found at any timepoint in the expression of TGF-alpha in BDL animals versus controls. In conclusion, the development of cirrhosis in this BDL rat model was associated with a progressive increase in the intrahepatic expression of EGF, bFGF, and TGF-beta. Early increased expression of HGF was not maintained in established cirrhosis. The findings suggest that these growth factors may play important roles in the pathogenesis of chronic hepatic regeneration in cirrhosis.

Patient transport from intensive care increases the risk of developing ventilator-associated pneumonia

STUDY OBJECTIVE

To determine whether patient transport out of the ICU is associated with an increased risk of developing ventilator-associated pneumonia.

DESIGN

Prospective cohort study.

SETTING

ICUs of Barnes-Jewish Hospital, a university-affiliated teaching hospital.

PATIENTS

Five hundred twenty-one ICU patients requiring mechanical ventilation for > 12 h.

INTERVENTION

Prospective patient surveillance and data collection.

MEASUREMENTS AND RESULTS

The primary outcome measure was the development of ventilator-associated pneumonia. A total of 273 (52.4%) mechanically ventilated patients required at least one transport out of the ICU while 248 (47.6%) patients did not undergo transport. Sixty-six (24.2%) of the transported patients developed ventilator-associated pneumonia compared with 11 (4.4%) patients in the group not undergoing transport (relative risk=5.5; 95% confidence interval [CI]=2.9 to 10.1; p<0.001). Multiple logistic regression analysis demonstrated that a preceding episode of transport out of the ICU was independently associated with the development of ventilator-associated pneumonia (adjusted odds ratio=3.8; 95% CI=2.6 to 5.5; p<0.001). Other variables independently associated with the development of ventilator-associated pneumonia included reintubation, presence of a tracheostomy, administration of aerosols, and male gender.

CONCLUSIONS

We conclude that patient transport out of the ICU is associated with an increased risk for the development of ventilator-associated pneumonia.

Mechanical ventilation with or without daily changes of in-line suction catheters

The purpose of this study was to determine the safety and cost-effectiveness of not routinely changing in-line suction catheters for patients requiring mechanical ventilation. Patients were randomly assigned to receive either no routine in-line suction catheter changes (n = 258) or in-line suction catheter changes every 24 h (n = 263). The main outcome measure was the incidence of ventilator-associated pneumonia. Other outcomes evaluated included hospital mortality, acquired organ system derangements, duration of mechanical ventilation, lengths of intensive care and hospital stay, and the cost for in-line suction catheters. Ventilator-associated pneumonia was seen in 38 patients (14.7%) receiving no routine in-line suction catheter changes and in 39 patients (14.8%) receiving in-line suction catheter changes every 24 h (relative risk, 0.99; 95% CI, 0.66 to 1.50). No statistically significant differences for hospital mortality, lengths of stay, the number of acquired organ system derangements, death in patients with ventilator-associated pneumonia, or mortality directly attributed to ventilator-associated pneumonia were found between the two treatment groups. Patients receiving in-line suction catheter changes every 24 h had 1,224 catheter changes costing a total of $11,016; patients receiving no routine in-line suction catheter changes had a total of 93 catheter changes costing $837. Our findings suggest that the elimination of routine in-line suction catheter changes is safe and can reduce the costs associated with providing mechanical ventilation.

A randomized, controlled trial of protocol-directed versus physician-directed weaning from mechanical ventilation

OBJECTIVE

To compare a practice of protocol-directed weaning from mechanical ventilation implemented by nurses and respiratory therapists with traditional physician-directed weaning.

DESIGN

Randomized, controlled trial.

SETTING

Medical and surgical intensive care units in two university-affiliated teaching hospitals.

PATIENTS

Patients requiring mechanical ventilation (n = 357).

INTERVENTIONS

Patients were randomly assigned to receive either protocol-directed (n = 179) or physician-directed (n = 178) weaning from mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was the duration of mechanical ventilation from tracheal intubation until discontinuation of mechanical ventilation. Other outcome measures included need for reintubation, length of hospital stay, hospital mortality rate, and hospital costs. The median duration of mechanical ventilation was 35 hrs for the protocol-directed group (first quartile 15 hrs; third quartile 114 hrs) compared with 44 hrs for the physician-directed group (first quartile 21 hrs; third quartile 209 hrs). Kaplan-Meier analysis demonstrated that patients randomized to protocol-directed weaning had significantly shorter durations of mechanical ventilation compared with patients randomized to physician-directed weaning (chi 2 = 3.62, p = .057, log-rank test; chi 2 = 5.12, p = .024, Wilcoxon test). Cox proportional-hazards regression analysis, adjusting for other covariates, showed that the rate of successful weaning was significantly greater for patients receiving protocol-directed weaning compared with patients receiving physician-directed weaning (risk ratio 1.31; 95% confidence interval 1.15 to 1.50; p = .039). The hospital mortality rates for the two treatment groups were similar (protocol-directed 22.3% vs. physician-directed 23.6%; p = .779). Hospital cost savings for patients in the protocol-directed group were $42,960 compared with hospital costs for patients in the physician-directed group.

CONCLUSION

Protocol-guided weaning of mechanical ventilation, as performed by nurses and respiratory therapists, is safe and led to extubation more rapidly than physician-directed weaning.

The Biosure Study: influence of composition of diet and food consumption on longevity, degenerative diseases and neoplasia in Wistar rats studied for up to 30 months post weaning

The 1200-rat Biosure Study had six interrelated aims: (1) To see whether dietary restriction (80% ad lib.) reduces the age-standardized incidence of fatal or potentially fatal neoplasia before the age of 30 months. (2) To see whether the beneficial effects of diet restriction can be achieved by (a) limiting the daily period of access to food to 6 hr, or by (b) limiting the energy value of the diet. (3) To see whether reduced calorie intake between weaning and age 4 months influences survival and/or incidence of non-neoplastic and neoplastic diseases. (4) To compare effects of food consumption, energy intake and protein intake on survival and disease. (5) To study the relationships between body weight at different ages with eventual survival and disease incidence. (6) To provide a database for studying relationships between various in-life measurements and eventual survival and disease incidence in individual animals. Twelve groups of SKF Wistar rats consisting of 50 animals of each sex were fed according to different dietary regimens from when they were weaned at the age of 3 wk until they died, or had to be killed because they were sick, or until the experiment was terminated at 30 months. For five of the 12 dietary regimens, satellite groups consisting of 30 animals per sex were maintained in parallel and used to supply information on the effect of diet on circulating hormone levels during the course of the study. During the 13 wk post weaning a Standard Breeder diet (SB) was provided either ad lib. (four groups), 80% ad lib. (three groups), or with access to food limited to 6 hr per day (one group). During this same period two other groups were fed a Low Nutrient Breeder diet (LB) ad lib. A further group was fed a Low Nutrient Maintenance (high fibre) diet (LM) ad lib. Finally, one group was fed the high protein Porton Rat diet (PR) ad lib.(ABSTRACT TRUNCATED AT 400 WORDS)

Pulmonary complications of trauma

Pulmonary complications can be the result of direct chest trauma or can occur from indirect trauma outside of the thorax. Understanding the mechanism of pulmonary function in determining intrapulmonary shunt and physiologic deadspace can assist the clinician in assessing the severity and monitoring the progression of pulmonary injury in patients. This article reviews assessment parameters, physiology, and treatment of direct and indirect pulmonary trauma.

Risks of premature death and cancer predicted by body weight in early adult life

In a study of 30 months duration, involving 600 male and 600 female Wistar rats fed on 12 different diets/dietary regimes, none of which involved deliberate exposure to any known genotoxic carcinogen, highly significant between-group differences were observed in survival and incidence of various neoplastic and non-neoplastic diseases. A full report of the findings is being prepared. Here we report that, irrespective of diet or dietary regime, there were highly significant correlations of body weight at 29 weeks of age with premature death (P less than 0.0001 in both males and females), with development of benign or malignant neoplasm of any site (P less than 0.0001 in males and P less than 0.01 in females) and with development of malignant neoplasm at any site (P less than 0.0001 for sexes combined). Numerous kinds of neoplasm contributed to these overall correlations. The most significant were pituitary tumour (P less than 0.0001), mammary gland tumour (P less than 0.0001), squamous or anaplastic carcinoma of the jaw (P less than 0.001), and subcutaneous mesodermal tumours (P less than 0.05). The 20% of rats that were heaviest at 29 weeks were more than twice as likely to die prematurely than the lightest 20% (2.56 times--males, and 2.11 times--females), and almost twice as likely to develop a malignant tumour (1.87 times for the sexes combined). These findings have important implications for the design and interpretation of carcinogenicity tests in rodents and of laboratory and human studies of relationships between diet, ageing-related degenerative diseases, and cancer.