Heart failure in general and cardiac transplant patients with COVID-19

Coronavirus disease 2019 (COVID-19) is primarily an infection of the respiratory tract, but it can have multisystem manifestations. Cardiac complications of COVID-19 can range from acute myocardial injury, cardiac arrhythmias, or heart failure, amongst others. Heart failure (HF) in COVID-19 can be a de novo process or due to worsening of pre-existing cardiovascular ailment. HF in a patient with COVID-19 not only poses challenges in clinical presentation and management of COVID-19 but also affect prognosis of the patient. This article aims to succinctly revisit the implications of this pandemic regarding pre-existing HF or new-onset HF based on prevailing data. It also focuses on the management and special recommendations from prior studies and guidelines.

Dexmedetomidine or Propofol for Sedation in Mechanically Ventilated Adults with Sepsis

BACKGROUND

Guidelines currently recommend targeting light sedation with dexmedetomidine or propofol for adults receiving mechanical ventilation. Differences exist between these sedatives in arousability, immunity, and inflammation. Whether they affect outcomes differentially in mechanically ventilated adults with sepsis undergoing light sedation is unknown.

METHODS

In a multicenter, double-blind trial, we randomly assigned mechanically ventilated adults with sepsis to receive dexmedetomidine (0.2 to 1.5 μg per kilogram of body weight per hour) or propofol (5 to 50 μg per kilogram per minute), with doses adjusted by bedside nurses to achieve target sedation goals set by clinicians according to the Richmond Agitation-Sedation Scale (RASS, on which scores range from -5 [unresponsive] to +4 [combative]). The primary end point was days alive without delirium or coma during the 14-day intervention period. Secondary end points were ventilator-free days at 28 days, death at 90 days, and age-adjusted total score on the Telephone Interview for Cognitive Status questionnaire (TICS-T; scores range from 0 to 100, with a mean of 50±10 and lower scores indicating worse cognition) at 6 months.

RESULTS

Of 432 patients who underwent randomization, 422 were assigned to receive a trial drug and were included in the analyses - 214 patients received dexmedetomidine at a median dose of 0.27 μg per kilogram per hour, and 208 received propofol at a median dose of 10.21 μg per kilogram per minute. The median duration of receipt of the trial drugs was 3.0 days (interquartile range, 2.0 to 6.0), and the median RASS score was -2.0 (interquartile range, -3.0 to -1.0). We found no difference between dexmedetomidine and propofol in the number of days alive without delirium or coma (adjusted median, 10.7 vs. 10.8 days; odds ratio, 0.96; 95% confidence interval [CI], 0.74 to 1.26), ventilator-free days (adjusted median, 23.7 vs. 24.0 days; odds ratio, 0.98; 95% CI, 0.63 to 1.51), death at 90 days (38% vs. 39%; hazard ratio, 1.06; 95% CI, 0.74 to 1.52), or TICS-T score at 6 months (adjusted median score, 40.9 vs. 41.4; odds ratio, 0.94; 95% CI, 0.66 to 1.33). Safety end points were similar in the two groups.

CONCLUSIONS

Among mechanically ventilated adults with sepsis who were being treated with recommended light-sedation approaches, outcomes in patients who received dexmedetomidine did not differ from outcomes in those who received propofol. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01739933.).

Intensive care unit complications and outcomes of adult patients with hemophagocytic lymphohistiocytosis: A retrospective study of 16 cases

AIM

To study the management, complications and outcomes of adult patients admitted with hemophagocytic lymphohistiocytosis (HLH) in the intensive care unit (ICU).

METHODS

We performed a retrospective observational study of adult patients with the diagnosis of “HLH” admitted to the two academic medical ICUs of Baylor College of Medicine between 01/01/2013 to 06/30/2017. HLH was diagnosed using the HLH-2004 criteria proposed by the Histiocyte Society.

RESULTS

Sixteen adult cases of HLH were admitted to the medical ICUs over 4 years. Median age of presentation was 49 years and 10 (63%) were males. Median Sequential Organ Failure Assessment (SOFA) score at the time of ICU admission was 10. Median ICU length of stay (LOS) was 11.5 d and median hospital LOS was 29 d. Septic shock and acute respiratory failure accounted for majority of diagnoses necessitating ICU admission. Septic shock was the most common ICU complication seen in (88%) patients, followed by acute kidney injury (81%) and acute respiratory failure requiring mechanical ventilation (75%). Nine patients (56%) developed disseminated intravascular coagulation and eight (50%) had acute liver failure. 10 episodes of clinically significant bleeding were observed. Multi system organ failure was the most common cause of death seen in 12 (75%) patients. The 30 d mortality was 37% (6 cases) and 90 d mortality was 81% (13 cases). There was no difference in mortality based on age (above or less than 50 years), SOFA score on ICU admission (more than or less than 10), immunosuppression, time to diagnose HLH or direct ICU admission versus floor transfer.

CONCLUSION

HLH is a devastating disease associated with poor outcomes in ICU. Intensivists need to have a high degree of clinical suspicion for HLH in patients with septic shock/multi system organ failure and progressive bi/pancytopenia who are not responding to standard management in ICU.

"Sacred Pause" in the ICU: Evaluation of a Ritual and Intervention to Lower Distress and Burnout

BACKGROUND

Increased exposure to deaths in the intensive care unit (ICU) generate grief among ICU staff, which remains unresolved most of the time. Unresolved grief becomes cumulative and presents a risk factor for burnout. "sacred pause" is a ritual performed at patient's death to honor the lost life and recognize the efforts of the health-care team.

OBJECTIVE

To study the impact of the ritual of sacred pause on the attitudes and behaviors of the ICU physicians and nurses.

METHODS

Ten-question online anonymous survey was sent to ICU physicians and nurses in the medical ICU of a tertiary care hospital in July 2017.

RESULTS

Thirty-four ICU team members completed the survey including 12 physicians and 22 nurses. Seventy sacred pause rituals were performed from July 2016 to June 2017. Seventy-nine percent respondents believed that the ritual brought closure and helped them overcome the feelings of disappointment, grief, distress, and failure after the death of their patient in ICU. Seventy-three percent agreed that the ritual has instilled and encouraged a sense of team effort. Eighty-two percent responded that the ritual makes their efforts feel appreciated. Many felt that the ritual should be a universal phenomenon in all ICUs. Only 55% respondents felt that the practice has a potential to decrease ICU burnout, many of them (42%) were undecided.

CONCLUSION

Sacred pause brings closure, prevents cumulative grief and distress, builds resilience, promotes team effort, and improves professional satisfaction of ICU team. It may lower burnout syndrome in ICU, but further studies are warranted.

Diagnosing obstructive lung disease

Preview There is considerable overlap in features and treatment of chronic obstructive pulmonary disease and asthma. Why, then, is it necessary to distinguish between the two? As the authors explain, the two diseases have different causes, risk factors, and clinical courses. Correct diagnosis, described in this article, allows physicians to take measures that reduce exacerbations and to accurately assess progress.

Effect of Yoga Breathing (Pranayama) on Exercise Tolerance in Patients with Chronic Obstructive Pulmonary Disease: A Randomized, Controlled Trial

OBJECTIVE

Pulmonary rehabilitation improves exercise tolerance in patients with chronic obstructive pulmonary disease (COPD). However, many patients do not have access to pulmonary rehabilitation programs. We hypothesized that an alternative to pulmonary rehabilitation to improve exercise tolerance is the practice of pranayama, or yoga breathing, which could be done independently at home. We also sought to determine whether yoga nonprofessionals could adequately teach pranayama to patients.

DESIGN

Proof-of-concept, randomized, double-blind, controlled pilot trial.

SETTINGS/LOCATION

Two academic pulmonary practices.

SUBJECTS

Forty-three patients with symptomatic, moderate-to-severe COPD.

INTERVENTIONS

Twelve weeks of pranayama plus education versus education alone. Two yoga professionals trained the research coordinators to conduct all pranayama teaching and monitored the quality of the teaching and the practice of pranayama by study participants.

OUTCOME MEASURES

The primary outcome was a change in the 6-min walk distance (6MWD). Secondary outcomes included changes in lung function, markers of oxidative stress and systemic inflammation, and measures of dyspnea and quality of life.

RESULTS

The 6MWD increased in the pranayama group (least square mean [95% confidence interval] = 28 m [-5 to 61]) and decreased in the control group (-15 m [-47 to 16]), with a nearly significant treatment effect (p = 0.06) in favor of pranayama. Pranayama also resulted in small improvements in inspiratory capacity and air trapping. Both groups had significant improvements in various measures of symptoms, but no overall differences in respiratory system impedance or markers of oxidative stress or systemic inflammation.

CONCLUSION

This pilot study successfully demonstrated that pranayama was associated with improved exercise tolerance in patients with COPD. Lay personnel were able to adequately teach patients to practice pranayama. These results suggest that pranayama may have significant clinical benefits for symptomatic patients with COPD, a concept that needs to be confirmed in future, larger clinical trials.

Update in Management of Severe Hypoxemic Respiratory Failure

Mortality related to severe-moderate and severe ARDS remains high. We searched the literature to update this topic. We defined severe hypoxemic respiratory failure as Pao₂/Fio₂ < 150 mm Hg (ie, severe-moderate and severe ARDS). For these patients, we support setting the ventilator to a tidal volume of 4 to 8 mL/kg predicted body weight (PBW), with plateau pressure (Pplat) ≤ 30 cm H₂O, and initial positive end-expiratory pressure (PEEP) of 10 to 12 cm H₂O. To promote alveolar recruitment, we propose increasing PEEP in increments of 2 to 3 cm provided that Pplat remains ≤ 30 cm H₂O and driving pressure does not increase. A fluid-restricted strategy is recommended, and nonrespiratory causes of hypoxemia should be considered. For patients who remain hypoxemic after PEEP optimization, neuromuscular blockade and prone positioning should be considered. Profound refractory hypoxemia (Pao₂/Fio₂ < 80 mm Hg) after PEEP titration is an indication to consider extracorporeal life support. This may necessitate early transfer to a center with expertise in these techniques. Inhaled vasodilators and nontraditional ventilator modes may improve oxygenation, but evidence for improved outcomes is weak.

Cleistanthus collinus poisoning: experience at a medical intensive care unit in a tertiary care hospital in south India

BACKGROUND & OBJECTIVES

Ingestion of Cleistanthus collinus causes hypokalemia and cardiac arrhythmias leading to mortality in most cases. We undertook this retrospective study to evaluate the clinical presentation and predictors of outcome in critically ill patients admitted with C. collinus poisoning.

METHODS

The case records of 56 patients admitted to the medical intensive care unit (MICU) of a tertiary care teaching hospital in south India (2000-2014) with C. collinus poisoning were retrospectively analysed.

RESULTS

The mean age of patients was 36.7±13.3 yr; there were 30 males. Salient clinical manifestations included hypokalemia (58%), neutrophilic leucocytosis (48.2%), acute kidney injury (AKI) (42.9%), acute respiratory failure requiring mechanical ventilation (AcRFMv) (32.1%), shock (21.4%); cardiac arrhythmias and neuromuscular weakness (19.6% each); 21 patients (37.5%) had adverse outcome. Longer time-lapsed from consumption to reaching emergency room [median (interquartile range)] (hours) [49 (22-97) vs. 28 (7-56), p =0.0380 ]; higher acute physiology and chronic health evaluation II (APACHE II) score at presentation [14 (8.25-14.75) vs. 2 (0-6) P<0.001]; and presence of the following [odds ratio (95% confidence intervals)] at initial presentation: shock [37.40 (4.29-325.98), P=0.001]; AcRFMv [26.67 (5.86-121.39), P<0.001]; elevated alanine aminotransferase [5.71 (1.30-25.03), p0 =0.021]; metabolic acidosis [5.48 (1.68-17.89), P=0.005]; acute kidney injury (AKI) [5 (1.55-16.06), P=0.007]; hyponatremia [4.67 (1.25-17.44), P=0.022]; and neutrophilic leucocytosis [3.80 (1.02-14.21), P=0.047] predicted death. A significant (P<0.001) increasing trend in mortality was observed with increasing International Program on Chemical Safety Poisoning Severity Score (IPCS-CSS) grade.

INTERPRETATION & CONCLUSIONS

C. collinus is a lethal poison associated with high mortality for which there is no specific antidote. Careful search and meticulous monitoring of the predictors of death and initiating appropriate corrective measures can be life saving.

Critical Illness in Pregnancy: Part II: Common Medical Conditions Complicating Pregnancy and Puerperium

The first of this two-part series on critical illness in pregnancy dealt with obstetric disorders. In Part II, medical conditions that commonly affect pregnant women or worsen during pregnancy are discussed. ARDS occurs more frequently in pregnancy. Strategies commonly used in nonpregnant patients, including permissive hypercapnia, limits for plateau pressure, and prone positioning, may not be acceptable, especially in late pregnancy. Genital tract infections unique to pregnancy include chorioamnionitis, group A streptococcal infection causing toxic shock syndrome, and polymicrobial infection with streptococci, staphylococci, and Clostridium perfringens causing necrotizing vulvitis or fasciitis. Pregnancy predisposes to VTE; D-dimer levels have low specificity in pregnancy. A ventilation-perfusion scan is preferred over CT pulmonary angiography in some situations to reduce radiation to the mother's breasts. Low-molecular-weight or unfractionated heparins form the mainstay of treatment; vitamin K antagonists, oral factor Xa inhibitors, and direct thrombin inhibitors are not recommended in pregnancy. The physiologic hyperdynamic circulation in pregnancy worsens many cardiovascular disorders. It increases risk of pulmonary edema or arrhythmias in mitral stenosis, heart failure in pulmonary hypertension or aortic stenosis, aortic dissection in Marfan syndrome, or valve thrombosis in mechanical heart valves. Common neurologic problems in pregnancy include seizures, altered mental status, visual symptoms, and strokes. Other common conditions discussed are aspiration of gastric contents, OSA, thyroid disorders, diabetic ketoacidosis, and cardiopulmonary arrest in pregnancy. Studies confined to pregnant women are available for only a few of these conditions. We have, therefore, reviewed pregnancy-specific adjustments in the management of these disorders.

Obstructive sleep apnea in pregnancy: reliability of prevalence and prediction estimates

OBJECTIVE

We sought to ascertain the validity of two screening scales for obstructive sleep apnea (OSA) in pregnancy and to establish the prevalence of OSA in pregnancy.

STUDY DESIGN

In this prospective observational study, two screening scales were administered. Screen positive subjects were referred for diagnostic polysomnography (PSG); if admitted for antepartum care, screen positive subjects underwent a modified study with a type 3 device (T3D).

RESULT

A total of 1509 subjects underwent OSA screening; 58 completed diagnostic testing. Neither measure was a reliable diagnostic tool for OSA as determined by T3D or PSG (detection rates of 10.3% and 18.0%, respectively). Among screen positive subjects undergoing PSG or T3D testing, 15.5% ultimately met 'gold standard' OSA diagnostic criteria for an estimated point prevalence of 4.9%.

CONCLUSION

In this prospective trial, screening positive on the Berlin questionnaire or Epworth sleepiness scale was poorly predictive of OSA among gravidae and was associated with a high false referral rate.

Burnout in the intensive care unit professionals

BACKGROUND

Professional burnout has been widely explored in health care. We conducted this study in our hospital intensive care unit (ICU) in United States to explore the burnout among nurses and respiratory therapists (RT).

MATERIALS AND METHODS

A survey consisting of two parts was used to assess burnout. Part 1 addressed the demographic information and work hours. Part 2 addressed the Maslach Burnout Inventory-Human Service Survey.

RESULTS

The analysis included 213 total subjects; Nurses 151 (71%) and RT 62 (29%). On the emotional exhaustion (EE) scale, 54% scored "Moderate" to "High" and 40% scored "Moderate" to "High" on the depersonalization (DP) scale. Notably 40.6% scored "Low" on personal accomplishment (PA) scale.

CONCLUSION

High level of EE, DP and lower PAs were seen among two groups of health care providers in the ICUs.

Comparison of anxiety, depression, and post-traumatic stress symptoms in relatives of ICU patients in an American and an Indian public hospital

Context:

An intensive care unit (ICU) admission of a patient causes considerable stress among relatives. Whether this impact differs among populations with differing sociocultural factors is unknown.

Aims:

The aim was to compare the psychological impact of an ICU admission on relatives of patients in an American and Indian public hospital.

Settings and Design:

A cross-sectional study was carried out in ICUs of two tertiary care hospitals, one each in major metropolitan cities in the USA and India.

Materials and Methods:

A total of 90 relatives visiting patients were verbally administered a questionnaire between 48 hours and 72 hours of ICU admission that included the Hospital Anxiety and Depression Scale (HADS), Beck Depression Inventory-II (BDI-II) and Impact of Events Scale-Revised (IES-R) for post-traumatic stress response.

Statistical Analysis:

Statistical analysis was done using the Mann-Whitney and chi-square tests.

Results:

Relatives in the Indian ICU had more anxiety symptoms (median HADS-A score 11 [inter-quartile range 9-13] vs. 4 [1.5-6] in the American cohort; P<0.0001), more depression symptoms (BDI-II score 14 [8.5-19] vs. 6 [1.5-10.5], P<0.0001) but a comparable post-traumatic stress response (IES-R score>30). 55% of all relatives had an incongruous perception regarding “change in the patient's condition” compared to the objective change in severity of illness. “Change in worry” was incongruous compared to the perception of improvement of the patient's condition in 78% of relatives.

Conclusions:

Relatives of patients in the Indian ICU had greater anxiety and depression symptoms compared to those in the American cohort, and had significant differences in factors that may be associated with this psychological impact. Both groups showed substantial discordance between the perceived and objective change in severity of illness.

Obstructive sleep apnea screening in pregnancy, perinatal outcomes, and impact of maternal obesity

We employed accepted, validated symptom-based screening measures to discern attributable risk of obstructive sleep apnea (OSA) to adverse pregnancy outcomes, taking into account potential maternal confounders. Commonly employed OSA screening measures (Berlin and Epworth scales) were performed in the second and third trimesters; maternal and neonatal outcome data were thereafter obtained. The relationship between OSA and outcomes of interest were explored in stratified and multivariate models controlling for potential confounders. The overall prevalence of OSA was 25.4%. Given a nonlinear increase by body mass index (BMI) strata (8.9%, 46%; p < 0.0001), stratified multivariate analysis was subsequently performed. Among nonobese (BMI <30) gravidae, frequency of preeclampsia was significantly higher among women with OSA (adjusted odds ratio = 6.58, 95% confidence interval = 1.04, 38.51; p = 0.035). Among the obese (BMI ≥30) gravidae, infant birth weight ratio (or birth weight by gestational age) was higher with OSA + screening than OSA - (1.099 versus 1.035; p = 0.04), and this association remained significant after adjustment for potential confounders (p = 0.05). OSA prevalence increases significantly among obese gravidae, raising concerns for the overall validity of commonly employed screening measures in pregnancy. Nevertheless, OSA status continues to exert an independent influence, as obese and nonobese gravidae are at increased risk for a limited number of adverse perinatal outcomes in multivariate models.

Management principles of the critically ill obstetric patient

The goals in management of critically ill obstetric patients involve intensive monitoring and physiologic support for patients with life-threatening but potentially reversible conditions. Management principles of the mother should also take the fetus and gestational age into consideration. The most common reasons for intensive care admissions (ICU) in the United States and United Kingdom are hypertensive disorders, sepsis, and hemorrhage. The critically ill obstetric patient poses several challenges to the clinicians involved in her care, because of the anatomic and physiologic changes that take place during pregnancy.

A multi-center, randomized, double-blind, parallel, placebo-controlled trial to evaluate the efficacy, safety, and pharmacokinetics of intravenous ibuprofen for the treatment of fever in critically ill and non-critically ill adults

Introduction

Hospitalized patients are often unable to ingest or tolerate oral antipyretics and recently an aqueous formulation of intravenous (IV) ibuprofen was approved by the US-FDA for the reduction of fever in adults.

Methods

We evaluated IV ibuprofen to reduce fever exceeding 101.0°F, measured as the percentage of subjects achieving a temperature <101.0°F at four hours after a single dose of IV ibuprofen vs. placebo. Secondary evaluations included the effect on temperature at 24 hours. Nine sites randomized patients to receive either a placebo or IV ibuprofen (100, 200, or 400 mg), and patients were given four hours for six doses. Subjects were excluded for platelet count <30 k and/or creatinine >3.0 mg/dL.

Results

At entry, there were no significant baseline differences between the IV ibuprofen group and placebo, n = 120. At four hours, the number (percentage) with T<101.0°F was: Placebo n = 9/28 (32%); 100 mg IV ibuprofen n = 19/31 (61%), P = 0.0264; 200 mg IV ibuprofen n = 21/30 (70%) P = 0.0043; 400 mg IV ibuprofen n = 24/31 (77%) P = 0.0005. A total of 53/120 patients (44%) were prospectively defined as critically ill at baseline and similar temperature reductions were observed in this subgroup. There were no statistically significant differences between treatment groups or when compared to placebo in transfusion, bleeding, renal failure or mortality.

Conclusions

All doses of IV ibuprofen tested reduced fever at four hours and throughout the first 24 hours of dosing. The 400 mg dose was effective in lowering temperature to normal and maintaining this over the first 24 hours of dosing. IV ibuprofen was effective in reducing fevers in critically ill and non-critically ill groups. Following 24 hours of administration of IV ibuprofen, no clinically significant differences in any safety parameter including renal function or bleeding occurred through the 28-day follow-up period.

Trial registrations

Clinicaltrials.gov registration number: NCT01131000.

Evaluation of obstructive lung disease with vibration response imaging

As optimal treatment and prognosis differ between asthma and COPD, a new diagnostic approach to differentiating between the two disorders would be clinically desirable. We evaluated the utility of vibration response imaging in differentiating between asthma and COPD. Sixty-six subjects with asthma or COPD were recorded, before and after the administration of a short-acting bronchodilator, using a computerized lung sound analysis device. Gray-scale images of breath sound distribution in the lungs, quantitative data in breath sound graphs (timing, amplitude) and automatic crackle and wheeze detection programs were used to differentiate between asthma and COPD subjects. Imaging data were compared with the clinical diagnosis, made by the standard methods (medical history, physical examination, and spirometric indices). Blinded evaluation of images demonstrated a significantly higher rate of improvement in image dynamics, shape and overall improvement following bronchodilator in subjects with asthma compared with those with COPD. Quantitative data showed distinct patterns in timing and amplitude for these two pathologies. Combined analyses based on qualitative image evaluation and quantitative data demonstrated an overall 85% accuracy (84% for asthma, 86% for COPD) in differentiating between asthma and COPD. Combined qualitative and quantitative evaluations of lung sounds are quite sensitive in distinguishing between lung sound recordings of COPD and asthma individuals. Lung sound features of synchronization in timing and intensity provide objective data that may further differentiate these two airway disorders.

Validation of automatic wheeze detection in patients with obstructed airways and in healthy subjects

Computerized lung-sound analysis is a sensitive and quantitative method to identify wheezing by its typical pattern on spectral analysis. We evaluated the accuracy of the VRI, a multi-sensor, computer-based device with an automated technique of wheeze detection. The method was validated in 100 sound files from seven subjects with asthma or chronic obstructive pulmonary disease and seven healthy subjects by comparison of auscultation findings, examination of audio files, and computer detection of wheezes. Three blinded physicians identified 40 sound files with wheezes and 60 sound files without wheezes. Sensitivity and specificity were 83% and 85%, respectively. Negative predictive value and positive predictive value were 89% and 79%, respectively. Overall inter-rater agreement was 84%. False positive cases were found to contain sounds that simulate wheezes, such as background noises with high frequencies or strong noises from the throat that could be heard and identified without a stethoscope. The present findings demonstrate that the wheeze detection algorithm has good accuracy, sensitivity, specificity, negative predictive value and positive predictive value for wheeze detection in regional analyses with a single sensor and multiple sensors. Results are similar to those reported in the literature. The device is user-friendly, requires minimal patient effort, and, distinct from other devices, it provides a dynamic image of breath sound distribution with wheeze detection output in less than 1 minute.

Mechanical ventilation for asthma: a 10-year experience

BACKGROUND

Asthmatics requiring admission to the intensive care unit and/or mechanical ventilation have increased morbidity and mortality. The purpose of this study is to examine morbidity and mortality in patients requiring intubation and mechanical ventilation for asthma over a 10-year period. This study also reviews the clinical features and management of these patients.

METHODS

We performed a retrospective review of medical records over a 10-year period of adult patients who required mechanical ventilation for a primary diagnosis of asthma. The study was conducted at a university-affiliated, county hospital.

RESULTS

One hundred twenty-seven patients with 162 episodes of asthma requiring mechanical ventilation were identified. The majority of the patients (64%) were women. The predominant ethnicity was African-American (65%). These patients had multiple risk factors for asthma mortality, including recent hospital admissions, prior episodes of near-fatal asthma, medication non-compliance, and poor outpatient follow-up. Over the 10 years of the study, outpatient management of these patients changed, with the percentage of admissions in which patients had been given inhaled corticosteroids increasing from 18 percent in 1990 to 80 percent in 1998. Management of mechanical ventilation also changed. The average tidal volume settings significantly decreased after 1995. The most common complication was atelectasis, which was seen in 33 cases. Evidence of barotrauma, including pneumothorax, pneumomediastinum, and subcutaneous emphysema, was present in 10 cases. There were four deaths. All four of the patients suffered cardiopulmonary arrest in the field with subsequent anoxic brain injury and withdrawal of care.

CONCLUSIONS

Although these patients had multiple risk factors for mortality from asthma, no deaths in this study were related to complications of mechanical ventilation. This low mortality may be related to changes in management of mechanical ventilation as well as changes in chronic outpatient asthma therapy.

Review of ventilatory techniques to optimize mechanical ventilation in acute exacerbation of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major global healthcare problem. Studies vary widely in the reported frequency of mechanical ventilation in acute exacerbations of COPD. Invasive intubation and mechanical ventilation may be associated with significant morbidity and mortality. A good understanding of the airway pathophysiology and lung mechanics in COPD is necessary to appropriately manage acute exacerbations and respiratory failure. The basic pathophysiology in COPD exacerbation is the critical expiratory airflow limitation with consequent dynamic hyperinflation. These changes lead to further derangement in ventilatory mechanics, muscle function and gas exchange which may result in respiratory failure. This review discusses the altered respiratory mechanics in COPD, ways to detect these changes in a ventilated patient and formulating ventilatory techniques to optimize management of respiratory failure due to exacerbation of COPD.

Acute severe asthma: recent advances

PURPOSE OF REVIEW

Acute severe asthma is challenging to the clinician both in terms of recognition and appropriate treatment. About 30% of these episodes need admission to the medical intensive care unit with a mortality of 8%. Relapse rates vary from 7 to 15% depending on how well the patient is managed. The purpose of this review is to discuss recent advances in identification of risk factors, pathophysiology and management of acute severe asthma.

RECENT FINDINGS

Although the exact mechanism for acute severe asthma is unclear, some that are implicated include inflammation, airway remodeling and downregulation of beta-receptors. None of the environmental factors have been clearly related to the development of near fatal attacks. Genetic polymorphisms have been associated with severe asthma. Lack of steroid responsiveness has been linked to severe asthma attacks. Chemokines and basement membrane changes characteristic of severe asthma are reported in a few studies. Lack of symptom perception in a certain group of patients with acute severe asthma leads to delayed interventions. Specific treatment modalities and ventilator management is reviewed.

SUMMARY

Severe asthma is a phenotype of asthma with variable pathology and clinical presentation. Early recognition and timely intervention is needed to prevent significant mortality and morbidity.

Hypotension is a predictor of mortality in acute exacerbations of chronic obstructive pulmonary disease

OBJECTIVES

To identify variables that predict the in-hospital course and prognosis of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

A retrospective analysis of 94 patients (20 females) with AECOPD. Twenty-one variables including arterial blood gas studies were analysed.

RESULTS

The mean age was 61.2 years. The in-hospital mortality rate was 12.8%; 28.6% of patients required invasive mechanical ventilation and 37.2% required ICU care. In univariate analysis, aypotension at presentation (systolic blood-pressure < 90 mmHg) [p = 0.002, odds ratio OR 10.95, 95% confidence interval (CI) 1.90-63.00); central cyanosis (p = 0.007, OR 6.91, 95% CI 1.42-33.59); and cor-pulmonale (p = 0.009, OR 10.46, 95% CI 1.26-86.46) were univariately associated with in-hospital mortality. On multivariate analysis, hypotension (p = 0.049, OR 18.419, 95% CI 1.013-334.752) remained the only independent predictor.

CONCLUSIONS

More than the markers of poor gas exchange, the presence of hypotension indicates a poor in-hospital prognosis in AECOPD.

Role of vocal cord function and dysfunction in patients presenting with symptoms of acute asthma exacerbation

A total of 48 patients presenting to the emergency department as acute asthma exacerbation were prospectively studied. Rhinolaryngoscopy was conducted with simultaneous flow measurements and spirometry performed before and after the procedure. Measurements of the vocal cord opening during various phases of respiration were analyzed. Only 4 of 48 patients had anterior two-thirds closure of the vocal cords with a diamond-shaped opening posteriorly during expiration. One additional patient had inspiratory and expiratory closure of the vocal cords. The previously unreported high incidence of anterior two-thirds closure (10.4%) of the vocal cords suggests that the upper airway has a role to play in a significant number of patients presenting with symptoms of asthma exacerbation.

Smoking and systemic disease

Cigarette smoking is associated with a number of adverse health effects, including well-established links to cardiopulmonary disease and several cancers. Some of the other important systemic diseases associated with smoking are the subjects of this article, such as diabetes mellitus and insulin resistance, and thyroid diseases. Also reviewed here is the impact of smoking on male and female infertility, on selected dermatologic conditions, and on gastrointestinal diseases including peptic ulcer and inflammatory bowel diseases.

Predictors of development and outcome in patients with acute respiratory distress syndrome due to tuberculosis

OBJECTIVE

To study the predictors of development and determinants of outcome in patients with acute respiratory distress syndrome (ARDS) due to tuberculosis (TB).

METHODS

Retrospective case-control study of demographic, clinical and laboratory data of hospitalised adult patients with active TB.

RESULTS

Of 2733 TB patients treated during 1980-2003, 29 (1.06%; 1.21 patients/year; mean age 31.6 +/- 10.9 years; 16 males) developed ARDS (cases). Seven had pulmonary TB and 22 had miliary TB (MTB); 298 (mean age 32.0 +/- 14.2 years; 110 males) who did not develop ARDS constituted controls. Presence of MTB (OR 4.6, 95%CI 1.2-17.8; P = 0.02), duration of illness beyond 30 days at presentation (OR 177.9, 95%CI 39-811.7; P < 0.001), absolute lymphocyte count < 1625/ mm3 (OR 4.5, 95%CI 1.1-19.3; P = 0.04) and serum ALT > 100 IU (OR 15.7, 95%CI 3.0-81.1, P < 0.001) were independent predictors of ARDS development. Twelve cases died (41.4%). Patients with APACHE II score >18; those with APACHE II score <18 in the presence of hyponatraemia and PaO2/FIO2 ratio <108.5 were likely to die.

CONCLUSIONS

In patients with TB, prolonged illness, MTB, absolute lymphocytopaenia and elevated ALT are independently associated with ARDS development. APACHE II score, serum sodium and PaO2/FIO2 ratio are determinants of outcome.

Neurologic disorders in pregnancy

BACKGROUND

Neurologic dysfunction, coma, and seizures are common in obstetric patients in the intensive care unit.

OBJECTIVE

To review common neurologic disorders resulting in critical illness in pregnancy.

REVIEW

Obstetric disorders causing coma and seizures include eclampsia, acute fatty liver of pregnancy, and amniotic fluid embolism. Preexisting disorders such as epilepsy may worsen in one-third of pregnant patients, and seizures are common during labor. Changes in hemodynamics, blood volume, and hormonal effects on the vessel wall increase risk of bleeding from berry aneurysms and arteriovenous malformations during pregnancy and the postpartum period. Acute intermittent porphyria produces seizures and hypertension, closely mimicking eclampsia. Cerebral venous sinus thrombosis is common in postpartum patients, especially in developing countries. Brain tumors invariably enlarge during pregnancy because of fluid retention and the presence of estrogen and progesterone receptors on tumor cells. Infections such as cerebral malaria and acute viral hepatitis with fulminant hepatic failure are common causes of coma and seizures during pregnancy in tropical regions of Asia, Africa, and Latin America. Patients may be admitted to the intensive care unit with type II respiratory failure due to myasthenic crisis, Guillain-Barre syndrome and spinal cord disease. Relapses of multiple sclerosis are infrequent during pregnancy but increase in the postpartum period.

CONCLUSIONS

In all instances, the effects of the disorders, diagnostic tests, and treatment on the fetus must be carefully weighed. Prompt delivery may be lifesaving for mother and fetus in conditions such as eclampsia and acute fatty liver of pregnancy; expectant treatment may be more appropriate in others.

Localization and upregulation of cysteinyl leukotriene-1 receptor in asthmatic bronchial mucosa

We have tested the hypothesis that the CysLT(1) receptor is expressed by a variety of bronchial mucosal immune cells and that the numbers of these cells increase in asthma, when stable and in exacerbations. We have applied in situ hybridization and immunohistochemistry to endobronchial biopsy tissue to identify and count inflammatory cells expressing CysLT(1) receptor mRNA and protein, respectively, and used double immunohistochemistry to identify the specific cell immunophenotypes expressing the receptor. Double-labeling demonstrated that bronchial mucosal eosinophils, neutrophils, mast cells, macrophages, B-lymphocytes, and plasma cells, but not T-lymphocytes, expressed the CysLT(1) receptor. The numbers of CysLT(1) receptor mRNA and protein positive inflammatory cells in nonsmoking, nonatopic control subjects without asthma were 13 and 16 mm(-2), respectively (median values; n = 15), and were significantly greater in stable asthma (50 and 43 mm(-2), respectively; n = 17; P < 0.001). Compared with stable asthma, there were further significant increases in subjects hospitalized for a severe exacerbation of their asthma (mRNA: median = 113 and protein: 156 mm(-2); n = 15; P < 0.002). For the combined data of both asthma subgroups, there were strong positive correlations between the increased numbers of CD45+ leukocytes and the greater numbers of cells expressing CysLT(1) receptor (mRNA: r = 0.60, P < 0.001; protein: r = 0.73, P < 0.0001). In conclusion, a variety of immunohistologically distinct inflammatory cells express the CysLT(1) receptor in the bronchial mucosa and both these and the total number of leukocytes increase in mild stable disease and increase further when there is a severe exacerbation of asthma.

Critically ill obstetric patients in an American and an Indian public hospital: comparison of case-mix, organ dysfunction, intensive care requirements, and outcomes

OBJECTIVE

To compare case-mix, health care practices, and outcome in obstetric ICU admissions in inner-city teaching hospitals in economically developed and developing countries.

DESIGN

Retrospective study.

SETTING

Ben Taub General Hospital (BTGH), Houston, Texas, and King Edward Memorial Hospital (KEMH), Mumbai, India.

PATIENTS

Women admitted during pregnancy or 6 weeks postpartum between 1992 and 2001.

MEASUREMENTS AND RESULTS

Patients from BTGH (n=174) and KEMH (n=754) had comparable age, number of organs affected, incidence of medical disorders (30%), liver dysfunction, and thrombocytopenia. Fewer KEMH patients received prenatal care (27 vs 86%) and came to hospital within 24 h of onset of symptoms (60 vs 90%). They had higher APACHE II scores (median 16 vs 10), greater incidence of neurological (63 vs 36%), renal (50 vs 37%), and cardiovascular dysfunction (39 vs 29%). Severe malaria, viral hepatitis, cerebral venous thrombosis, and poisoning were common medical disorders. The BTGH group had higher incidence of respiratory dysfunction (59 vs 46%) and disseminated intravascular coagulation (40 vs 23%), placental anomalies, HELLP syndrome, chorioamnionitis, peripartum cardiomyopathy, puerperal sepsis, urinary infection, bacteremia, substance abuse, and asthma. More BTGH patients required mechanical ventilation and blood component therapy, whereas more KEMH patients needed dialysis. Of BTGH patients, 78.2% were delivered by cesarean section (vs 15.4%). Maternal (2.3 vs 25%) and fetal (13 vs 51%) mortality were lower in BTGH patients.

CONCLUSIONS

There were marked differences in medical diseases, organ failure, and intensive care needs. Higher mortality in the Indian ICU may be due to difference in case mix, inadequate prenatal care, delay in reaching hospital, and greater severity of illness.

Effect of airway pressure display on interobserver agreement in the assessment of vascular pressures in patients with acute lung injury and acute respiratory distress syndrome*

BACKGROUND

Previous investigations have identified significant interobserver variability in the measurements of central venous pressure and pulmonary artery occlusion pressure in critically ill patients. Large interobserver variability in the measurement of vascular pressures could potentially lead to inappropriate treatment decisions.

OBJECTIVE

We postulated that adding an airway pressure signal (Paw) to pressure tracings of central venous pressure and pulmonary artery occlusion pressure would improve interobserver agreement by facilitating identification of end-expiration.

DESIGN

To test this hypothesis, six independent experts used a standard protocol to interpret strip-chart recordings of central venous pressure and pulmonary artery occlusion pressure with or without Paw. Two observers were said to agree if their measurements were within 2 mm Hg of each other. SETTING/SUBJECTS/INTERVENTIONS: A total of 459 strip-chart recordings (303 without Paw and 156 with Paw) were obtained from 121 patients enrolled in the ARDSnet Fluids and Catheters Treatment Trial (FACTT) in 16 different hospitals.

RESULTS

Agreement within 2 mm Hg between two measurements was 79% for central venous pressure strips without Paw vs. 86% with Paw. For pulmonary artery occlusion pressure, agreement increased from 71% without Paw to 83% with Paw. The increase in agreement with the addition of Paw was greater for strips demonstrating >8 mm Hg phasic respiratory variation compared with strips demonstrating less phasic respiratory variation.

CONCLUSION

Paw display is a simple, inexpensive method to facilitate the identification of end-expiration that can significantly improve interobserver agreement.

Critical illness and pregnancy: review of a global problem

Obstetric patients are a small but important group of patients in the intensive care unit (ICU). Their problems are unique and need specialized attention. Decision making may be confounded by physiologic changes in pregnancy. In developed countries with good antenatal care, comparatively fewer obstetric patients are admitted to ICUs, but the maternal mortality rate remains high in the developing countries. Medical disorders and organ dysfunction caused by critical illness of pregnancy differ from region to region. With improvement in antenatal care, the number of ICU admissions for obstetric disorders would decline in developing countries; however, this number may increase gradually in developed countries because of increasing maternal age and pregnancies in women with complicated chronic medical disorders.

Smoking and systemic disease

Cigarette smoking is associated with a number of adverse health effects, including well-established links to cardiopulmonary disease and several cancers. Some of the other important systemic diseases associated with smoking are the subjects of this article, such as diabetes mellitus and insulin resistance and thyroid diseases. Also reviewed here is the negative impact of smoking on male and female infertility, on selected dermatologic conditions, and on gastrointestinal diseases including peptic ulcer and inflammatory bowel diseases.

Respiratory failure in interstitial lung disease

PURPOSE OF REVIEW

Respiratory failure associated with interstitial lung disease (ILD) occurs commonly, often as a terminal event after a prolonged course of illness. Diagnosis and management of the underlying ILD and respiratory failure pose great challenges.

RECENT FINDINGS

Respiratory failure in the absence of a clearly identifiable cause has a high mortality and frequent complications. Patients with idiopathic pulmonary fibrosis who are admitted with respiratory failure have a grim prognosis and may not benefit from prolonged aggressive therapy including mechanical ventilation. Presence of diffuse alveolar damage or usual interstitial pneumonia on lung biopsy specimens from patients with respiratory failure may be a marker of poor prognosis. Recently, the importance of the clinical-radiologic-pathologic diagnosis has been emphasized.

SUMMARY

The prognosis and treatment may vary according to the type of ILD and the cause of the respiratory failure, which must therefore be established before treatment is initiated. Prevention of iatrogenesis and timely application of palliation are as important as specific treatment of underlying ILD.

Early thickening of the reticular basement membrane in children with difficult asthma

Remodeling of the airway wall occurs in adults with asthma, and reticular basement membrane (RBM) thickening is pathognomonic of the asthma process. To investigate whether RBM thickening is present in children with difficult asthma and comparable to that seen in adults with asthma, we used light microscopy to measure RBM thickness in plastic-embedded endobronchial biopsy sections from 19 children with difficult asthma who were prescribed 1,600 microg/day or more of inhaled steroids (age range, 6-16 years), 10 children without asthma (7-16 years), and three adult groups: 8 healthy control subjects (21-42 years), 10 mild steroid-naive subjects with asthma (18-41 years), and 6 adults (3 steroid naive and 3 on inhaled steroids) intubated after a life-threatening attack of asthma (20-64 years). RBM thickness in the children with asthma was similar to that in adults with either mild or life-threatening asthma (median 8.2 [range 5.4-11.1] versus 8.1 [5.8-10.0] and 7.2 [2.8-10.0] microm, respectively) and greater than either adult or pediatric control subjects (8.2 [5.4-11.1] versus 4.4 [3.2-6.3] microm, p < 0.01, and 4.9 [3.7-8.3] microm, p < 0.01). We conclude that RBM thickening is already present in children with difficult asthma and to a similar extent to that seen in adults with asthma. In addition, we find no association with age, symptom duration, lung function, or concurrent eosinophilic airway inflammation.

The effect of heliox-driven bronchodilator aerosol therapy on pulmonary function tests in patients with asthma

To compare the effects of heliox-driven (He 80:O2 20) to air-driven (N 79:O2 21) beta2-agonist aerosol therapy on pulmonary function tests (PFTs) in patients with asthma, a prospective randomized crossover study was undertaken in the asthma clinic of the university-affiliated county hospital in Houston, TX. Thirty-one patients (22 female, age range 18-44) with clinically stable asthma consented. All patients were studied on two different days with both heliox and air as driving gas, therefore serving as their own controls. The PFTs including forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), maximal mid-expiratory flow rate (FEF(25-75)), and maximal expiratory flow rate (FEFmax) were obtained while breathing ambient air at baseline and 30 min after the bronchodilator treatment. Albuterol sulfate 2.5 mg was nebulized with either heliox or compressed air at 8 L/min for 8 min. When heliox was used as driving agent, additional heliox was delivered via a closed system and no entrainment of external air was allowed. Primary outcome measure was absolute change in FEV1 (deltaFEV1). There were no statistically significant differences in baseline PFTs on the two days of the study. All patients had good bronchodilator response (> or = 12% improvement in FEV1) with either driving gas. The deltaFEV1 after heliox-driven bronchodilator (HDBD) and air-driven bronchodilator (ADBD) were 0.68+/-0.38 L/sec (CI: 0.54-0.82) vs. 0.51+/-0.26 L/sec (CI: 0.42-0.60), respectively (p=0.004). The deltaFEV1 with HDBD was 49+/-90% (range -36% to 433%) more than ADBD. A subgroup analysis showed this was largely due to better response rates in patients with moderate to severe obstruction. There was more improvement in both FVC and FEFmax with HDBD than ADBD (p<0.05). The changes in FEF(25-75) were similar. We conclude that HDBD therapy improves FEV1, FVC, and FEFmax significantly more than ADBD in patients with asthma. Further large randomized studies are needed to better characterize responders and the impact on clinical outcomes.