Clinical Instructor, Medicine
Acetazolamide and N-acetylcysteine in the treatment of chronic mountain sickness (Monge's disease)
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
2017; 246: 1–8
Patients suffering from chronic mountain sickness (CMS) have excessive erythrocytosis. Low -level cobalt toxicity as a likely contributor has been demonstrated in some subjects. We performed a randomized, placebo controlled clinical trial in Cerro de Pasco, Peru (4380m), where 84 participants with a hematocrit (HCT) ≥65% and CMS score>6, were assigned to four treatment groups of placebo, acetazolamide (ACZ, which stimulates respiration), N-acetylcysteine (NAC, an antioxidant that chelates cobalt) and combination of ACZ and NAC for 6 weeks. The primary outcome was change in hematocrit and secondary outcomes were changes in PaO2, PaCO2, CMS score, and serum and urine cobalt concentrations. The mean (±SD) hematocrit, CMS score and serum cobalt concentrations were 69±4%, 9.8±2.4 and 0.24±0.15μg/l, respectively for the 66 participants. The ACZ arm had a relative reduction in HCT of 6.6% vs. 2.7% (p=0.048) and the CMS score fell by 34.9% vs. 14.8% (p=0.014) compared to placebo, while the reduction in PaCO2 was 10.5% vs. an increase of 0.6% (p=0.003), with a relative increase in PaO2 of 13.6% vs. 3.0%. NAC reduced CMS score compared to placebo (relative reduction of 34.0% vs. 14.8%, p=0.017), while changes in other parameters failed to reach statistical significance. The combination of ACZ and NAC was no better than ACZ alone. No changes in serum and urine cobalt concentrations were seen within any treatment arms. ACZ reduced polycythemia and CMS score, while NAC improved CMS score without significantly lowering hematocrit. Only a small proportion of subjects had cobalt toxicity, which may relate to the closing of contaminated water sources and several other environmental protection measures.
View details for PubMedID 28720395
Evaluation of a novel 5-group classification system of sepsis by vasopressor use and initial serum lactate in the emergency department.
Internal and emergency medicine
Prognostication in sepsis is limited by disease heterogeneity, and measures to risk-stratify patients in the proximal phases of care lack simplicity and accuracy. Hyperlactatemia and vasopressor dependence are easily identifiable risk factors for poor outcomes. This study compares incidence and hospital outcomes in sepsis based on initial serum lactate level and vasopressor use in the emergency department (ED). In a retrospective analysis of a prospectively identified dual-center ED registry, patients with sepsis were categorized by ED vasopressor use and initial serum lactate level. Vasopressor-dependent patients were categorized as dysoxic shock (lactate >4.0 mmol/L) and vasoplegic shock (≤4.0 mmol/L). Patients not requiring vasopressors were categorized as cryptic shock major (lactate >4.0 mmol/L), cryptic shock minor (>2.0 and ≤4.0 mmol/L), and sepsis without lactate elevation (≤2.0 mmol/L). Of 446 patients included, 4.9% (n = 22) presented in dysoxic shock, 11.7% (n = 52) in vasoplegic shock, 12.1% (n = 54) in cryptic shock major, 30.9% (n = 138) in cryptic shock minor, and 40.4% (n = 180) in sepsis without lactate elevation. Group mortality rates at 28 days were 50.0, 21.1, 18.5, 12.3, and 7.2%, respectively. After adjusting for potential confounders, odds ratios for mortality at 28 days were 15.1 for dysoxic shock, 3.6 for vasoplegic shock, 3.8 for cryptic shock major, and 1.9 for cryptic shock minor, when compared to sepsis without lactate elevation. Lactate elevation is associated with increased mortality in both vasopressor dependent and normotensive infected patients presenting to the emergency department (ED). Cryptic shock mortality (normotension + lactate >4 mmol/L) is equivalent to vasoplegic shock mortality (vasopressor requirement + lactate <4 mmol/L) in our population. The odds of normotensive, infected patients decompensating is three to fourfold higher with hyperlactemia. The proposed Sepsis-3 definitions exclude an entire group of high-risk ED patients. A simple classification in the ED by vasopressor requirement and initial lactate level may identify high-risk subgroups of sepsis. This study may inform prognostication and triage decisions in the proximal phases of care.
View details for DOI 10.1007/s11739-017-1607-y
View details for PubMedID 28132131
Composition of the Sepsis Definitions Task Force
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
2016; 316 (4): 460
View details for PubMedID 27458964