Guillermo Domínguez-Cherit

Critically Ill Patients With 2009 Influenza A(H1N1) in Mexico

CONTEXT In March 2009, novel 2009 influenza A(H1N1) was first reported in the southwestern United States and Mexico. The population and health care system in Mexico City experienced the first and greatest early burden of critical illness. OBJECTIVE To describe baseline characteristics, treatment, and outcomes of consecutive critically ill patients in Mexico hospitals that treated the majority of such patients with confirmed, probable, or suspected 2009 influenza A(H1N1). DESIGN, SETTING, AND PATIENTS Observational study of 58 critically ill patients with 2009 influenza A(H1N1) at 6 hospitals between March 24 and June 1, 2009. Demographic data, symptoms, comorbid conditions, illness progression, treatments, and clinical outcomes were collected using a piloted case report form. MAIN OUTCOME MEASURES The primary outcome measure was mortality. Secondary outcomes included rate of 2009 influenza (A)H1N1-related critical illness and mechanical ventilation as well as intensive care unit (ICU) and hospital length of stay. RESULTS Critical illness occurred in 58 of 899 patients (6.5%) admitted to the hospital with confirmed, probable, or suspected 2009 influenza (A)H1N1. Patients were young (median, 44.0 [range, 10-83] years); all presented with fever and all but 1 with respiratory symptoms. Few patients had comorbid respiratory disorders, but 21 (36%) were obese. Time from hospital to ICU admission was short (median, 1 day [interquartile range {IQR}, 0-3 days]), and all patients but 2 received mechanical ventilation for severe acute respiratory distress syndrome and refractory hypoxemia (median day 1 ratio of Pao(2) to fraction of inspired oxygen, 83 [IQR, 59-145] mm Hg). By 60 days, 24 patients had died (41.4%; 95% confidence interval, 28.9%-55.0%). Patients who died had greater initial severity of illness, worse hypoxemia, higher creatine kinase levels, higher creatinine levels, and ongoing organ dysfunction. After adjusting for a reduced opportunity of patients dying early to receive neuraminidase inhibitors, neuraminidase inhibitor treatment (vs no treatment) was associated with improved survival (odds ratio, 8.5; 95% confidence interval, 1.2-62.8). CONCLUSION Critical illness from 2009 influenza A(H1N1) in Mexico occurred in young individuals, was associated with severe acute respiratory distress syndrome and shock, and had a high case-fatality rate.

Pressure-induced Rhabdomyolysis after Bariatric Surgery

Rhabdomyolisis most commonly occurs after muscle injury, alcohol ingestion, drug intake and exhaustive exercise. Prolonged muscle compression at the time of surgery may produce this complication. Obesity has been reported as a risk factor for pressure-induced rhabdomyolysis, but no reports associated with bariatric surgery could be found in the literature. We report 3 superobese patients who developed rhabdomyolysis after bariatric surgery. This complication was attributed to direct and prolonged pressure of the bed against the dorsal and gluteal muscles.

Anesthesia for Morbidly Obese Patients

Abstract. Bariatric surgery is the most effective method for treating patients with morbid obesity, and participation of the anesthesiologist in the treatment of these patients is more and more frequent. Therefore it is important for anesthesiologists to be familiar with anatomic and physiologic implications and the pharmacologic changes associated with obesity, so they can offer optimal perioperative treatment. The present study describes a series of 37 patients with an average body mass index of 50.3 kg/m 2 who underwent bariatric surgery in a third-level teaching hospital in Mexico City. Preoperative assessment, airway management, perioperative treatment, and the incidence of complications are analyzed. We found a high frequency of associated diseases, among which diabetes mellitus and systemic arterial hypertension were the most prominent. Cardiorespiratory complications such as obstructive sleep apnea syndrome and obesity-hypoventilation syndrome were particularly frequent (16.2% and 22.0%, respectively). Both general anesthesia and mixed anesthesia (peridural block plus light general anesthesia) were employed. The incidence of complications related to perioperative and anesthetic management was low. We discuss and propose protocols for the evaluation and management of airway and associated cardiorespiratory complications.

Impact of surgically-induced weight loss on respiratory function: a prospective analysis.

Background: Morbid obesity (MO) causes several degrees of respiratory impairment that may resolve after weight reduction. The aims of the present study were to investigate the frequency of respiratory impairment in a selected cohort of morbidly obese patients with BMI 40-50 kg/m2 with no respiratory symptoms and to evaluate the impact of surgically-induced weight loss on respiratory function. Methods: Prospective analysis of respiratory impairment was conducted before surgery and 1 year after surgery in a cohort of patients with MO who underwent vertical banded gastroplasty (VBG). 30 consecutive patients with MO who underwent VBG (14 open and 16 laparoscopic) in a 1-year period were studied. Respiratory function tests, arterial blood gases and hemoglobin were obtained in all patients before and 1 year after VBG. Results: Results were analyzed using the Wilcoxon signed-rank test and Spearman for variables without normal distribution. Mean age was 35±8 years; there were 3 males and 27 females. BMI was 44±4 kg/m2 before surgery and 32±4 kg/m2 at 1-year follow-up. By respiratory function tests, the diagnosis of obstructive disease was made before surgery in 4 patients and a restrictive disorder was identified in 4 additional patients. Evidence of pulmonary disease was absent in all patients 1 year after surgery. Forced vital capacity, inspiratory and expiratory forces, tidal volume, SaO2, and PaCO2 significantly improved after weight reduction. Conclusion: Surgically-induced weight loss significantly improves pulmonary function.

Open versus laparoscopic vertical banded gastroplasty: a randomized controlled double blind trial.

Background:Vertical banded gastroplasty (VBG) is a frequently used surgical procedure for the treatment of morbid obesity. It can be done open (OVBG) or laparoscopic (LVBG). The aim of this double-blind randomized clinical trial was to compare the postoperative outcome and 1-year follow-up of 2 cohorts of patients who underwent either OVBG or LVBG. Patients and Methods: 30 patients with morbid obesity were randomized into 2 groups (14 OVBG and 16 LVBG). Pain intensity, analgesic requirements, respiratory function, and physical activity were blindly analyzed during the first 3 postoperative days. Complications, weight loss, and cosmetic results after 1 year follow-up were evaluated. Results: Both groups were highly comparable before surgery. Surgical time was longer in the laparoscopic procedure. Patients in this group required less analgesics during the first postoperative day.There was an earlier recovery in the expiratory and inspiratory forces, as well as faster recovery of physical activities in patients who underwent LVBG. Postoperative complications were more frequent in the open group. Excess body weight loss after 1 year was similar in both groups. Cosmetic results were significantly better in the laparoscopic group. Conclusions: LVBG had advantages over the open procedure in terms of analgesic requirements, respi function, postoperative recovery, and cosmetic results.

Prognostic factors in patients with systemic lupus erythematosus admitted to the intensive care unit.

The objectives of this study were to identify risk factors associated with mortality in patients with systemic lupus erythematosus (SLE) admitted to the intensive care unit (ICU) and to evaluate the usefulness of Acute Physiologic and Chronic Health Evaluation (APACHE) II score to predict outcomes in these patients, through the use of a retrospective patient record review from a multidisciplinary intensive care unit in a teaching hospital. One hundred and four patients with SLE admitted to the ICU were included in the study. The mean age of patients was 32.44 years, 96.2% were female and 61.5% were admitted with infection. The mean APACHE II score was 19.7, 46.2% had acute renal dysfunction, 67.3% received inotropics/ vasopressors, 27.9% pulmonary artery catheter and 74% invasive mechanical ventilation. The mean length of stay in ICU was 18.5 days and mortality rate was 32.7%. In the univariate logistic regression analysis, factors associated with mortality were high APACHE II score, use of inotropics/vasopressors, pulmonary artery catheter and invasive mechanical ventilation. High APACHE II score and use of inotropics/vasopressors remained significant in the multi-variate analysis. The area under the receiver operating characteristic curve of the APACHE II score to predict mortality was 0.689 (95% CI 0.586—0.791 p = 0.002) and the Hosmer— Lemeshow χ 2 was 5.094 (p = 0.747). We conclude that the mortality rate in patients with SLE admitted to the ICU is high. The most common cause of admission was infection. The factors associated with mortality were high APACHE II score and the use of inotropics/vasopressors. APACHE II score was unable to accurately predict mortality. Lupus (2009) 18, 1252—1258.

H1N1 influenza pandemic of 2009 compared with other influenza pandemics: epidemiology, diagnosis, management, pulmonary complications, and outcomes.

Influenza pandemics are complex events that have occurred frequently throughout human history, three during the past century alone. Now the world is facing the first 21st century pandemic, and the comparison among them is essential to identify common epidemiologic patterns, clinical characteristics, and outcomes. The evolution of medicine, including diagnostic and treatment options, the critical care advances, and global responses are new interventions that could modify the general outcome of the pandemic. Learning from past and current events could lead to a plan for prompt and efficient response in future pandemics and may be help us to predict the unpredictable.

A Canadian Critical Care Trials Group project in collaboration with the international forum for acute care trialists - Collaborative H1N1 Adjuvant Treatment pilot trial (CHAT): study protocol and design of a randomized controlled trial

BackgroundSwine origin influenza A/H1N1 infection (H1N1) emerged in early 2009 and rapidly spread to humans. For most infected individuals, symptoms were mild and self-limited; however, a small number developed a more severe clinical syndrome characterized by profound respiratory failure with hospital mortality ranging from 10 to 30%. While supportive care and neuraminidase inhibitors are the main treatment for influenza, data from observational and interventional studies suggest that the course of influenza can be favorably influenced by agents not classically considered as influenza treatments. Multiple observational studies have suggested that HMGCoA reductase inhibitors (statins) can exert a class effect in attenuating inflammation. The Collaborative H1N1 Adjuvant Treatment (CHAT) Pilot Trial sought to investigate the feasibility of conducting a trial during a global pandemic in critically ill patients with H1N1 with the goal of informing the design of a larger trial powered to determine impact of statins on important outcomes.Methods/DesignA multi-national, pilot randomized controlled trial (RCT) of once daily enteral rosuvastatin versus matched placebo administered for 14 days for the treatment of critically ill patients with suspected, probable or confirmed H1N1 infection. We propose to randomize 80 critically ill adults with a moderate to high index of suspicion for H1N1 infection who require mechanical ventilation and have received antiviral therapy for ≤ 72 hours. Site investigators, research coordinators and clinical pharmacists will be blinded to treatment assignment. Only research pharmacy staff will be aware of treatment assignment. We propose several approaches to informed consent including a priori consent from the substitute decision maker (SDM), waived and deferred consent. The primary outcome of the CHAT trial is the proportion of eligible patients enrolled in the study. Secondary outcomes will evaluate adherence to medication administration regimens, the proportion of primary and secondary endpoints collected, the number of patients receiving open-label statins, consent withdrawals and the effect of approved consent models on recruitment rates.DiscussionSeveral aspects of study design including the need to include central randomization, preserve allocation concealment, ensure study blinding compare to a matched placebo and the use novel consent models pose challenges to investigators conducting pandemic research. Moreover, study implementation requires that trial design be pragmatic and initiated in a short time period amidst uncertainty regarding the scope and duration of the pandemic.Trial Registration NumberISRCTN45190901

Influenza A (H1N1pdm09)-Related Critical Illness and Mortality in Mexico and Canada, 2014.

Objectives:The 2009–2010 influenza A (H1N1pdm09) pandemic caused substantial morbidity and mortality among young patients; however, mortality estimates have been confounded by regional differences in eligibility criteria and inclusion of selected populations. In 2013–2014, H1N1pdm09 became North America’s dominant seasonal influenza strain. Our objective was to compare the baseline characteristics, resources, and treatments with outcomes among critically ill patients with influenza A (H1N1pdm09) in Mexican and Canadian hospitals in 2014 using consistent eligibility criteria. Design:Observational study and a survey of available healthcare setting resources. Setting:Twenty-one hospitals, 13 in Mexico and eight in Canada. Patients:Critically ill patients with confirmed H1N1pdm09 during 2013–2014 influenza season. Interventions:None. Measurements and Main Results:The main outcome measures were 90-day mortality and independent predictors of mortality. Among 165 adult patients with H1N1pdm09-related critical illness between September 2013 and March 2014, mean age was 48.3 years, 64% were males, and nearly all influenza was community acquired. Patients were severely hypoxic (median PaO2-to-FIO2 ratio, 83 mm Hg), 97% received mechanical ventilation, with mean positive end-expiratory pressure of 14 cm H2O at the onset of critical illness and 26.7% received rescue oxygenation therapy with prone ventilation, extracorporeal life support, high-frequency oscillatory ventilation, or inhaled nitric oxide. At 90 days, mortality was 34.6% (13.9% in Canada vs 50.5% in Mexico, p < 0.0001). Independent predictors of mortality included lower presenting PaO2-to-FIO2 ratio (odds ratio, 0.89 per 10-point increase [95% CI, 0.80–0.99]), age (odds ratio, 1.49 per 10 yr increment [95% CI, 1.10–2.02]), and requiring critical care in Mexico (odds ratio, 7.76 [95% CI, 2.02–27.35]). ICUs in Canada generally had more beds, ventilators, healthcare personnel, and rescue oxygenation therapies. Conclusions:Influenza A (H1N1pdm09)-related critical illness still predominantly affects relatively young to middle-aged patients and is associated with severe hypoxemic respiratory failure. The local critical care system and available resources may be influential determinants of patient outcome.

Pulmonary hypertension secondary to hyperviscosity in a patient with rheumatoid arthritis and acquired von Willebrand disease: a case report

IntroductionAcquired von Willebrand disease is initiated by autoantibodies and hyperviscosity syndrome caused by a massive polyclonal hypergammaglobulinemia. Acquired von Willebrand disease associated with autoimmune disease in addition to pulmonary hypertension during emergency room presentation is a rare condition. To the best of our knowledge, this is the second case reported in the literature treated with success; the first one was reported in 1987.Case presentationA 28-year-old mestizo man with a 3-year history of inflammatory arthritis was admitted to our hospital. An overlap of rheumatoid arthritis with systemic lupus erythematosus was suspected; therefore methotrexate was initiated, and later changed to leflunomide because of liver toxicity. Prothrombin time, international normalized ratio and activated partial thromboplastin times were normal (11/10.4 seconds; 1.2; 31.1/26.9 seconds, respectively), von Willebrand factor activity was observed with low ristocetin cofactor at 33.6UI/dL, high von Willebrand factor antigen >200UI/dL, and a low von Willebrand factor: ristocetin cofactor to von Willebrand factor antigen ratio. He was admitted to the emergency room with a 24-hour evolution of progressive dyspnea, cough, thoracic pain, and palpitations, 104 beats/min, 60/40 mmHg, temperature of 38°C, pulse oximetric saturation 88% and 30 breaths/minute. Cold, pale and mottled skin was also observed. He was then transferred to the intensive care unit. The placement of a pulmonary artery catheter was made. The initial patterns showed a precapillary pulmonary hypertension; acute pulmonary embolism was the first choice for diagnosis. Pulmonary angiography was conducted, and when no clot was discovered, pulmonary artery hypertension associated with connective tissue disease was considered. Serum protein electrophoresis confirmed the presence of a massive polyclonal hypergammaglobulinemia, and no paraproteinemia or monoclonal cell population was found from the electrophoretic pattern of the patient’s plasma. Hypergammaglobulinemia was the cause of hyperviscosity syndrome associated with autoantibodies. Three sessions of plasma exchange therapy were made, and clinical improvement was observed. He was then discharged from the intensive care unit and hospital, respectively. He is now attended by an external consult and has no respiratory symptomatology.ConclusionsHyperviscosity syndrome with pulmonary arterial hypertension presentation in a patient with acquired von Willebrand disease in an autoimmune context is a rare condition that can be treated successfully with plasmapheresis and critical care support.