Amphetamines and cannabinoids testing in hair: Evaluation of results from a two-year period.

This paper presents an overview of a set of amphetamines and cannabinoids tests performed on head hair samples from the Medico-Legal sector at the Madrid Department of the Spanish National Institute of Toxicology and Forensic Sciences during the years 2013 and 2014. The hair samples were tested for five stimulant phenylalkylamine derivatives -amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxy-amphetamine (MDA), and 3,4-methylenedioxy-N-ethylamphetamine (MDEA)- and/or two cannabinoids-Δ(9)-tetrahydrocannabinol (THC) and cannabinol (CBN)- by gas chromatography equipped with mass spectrometry detection in selected-ion monitoring mode, applying a method accredited to ISO/IEC 17025 standards. The test results were interpreted according to the confirmation cut-offs proposed by the Society of Hair Testing (SoHT) to identify chronic drug use. The ratios of positive results were studied in relation to gender, age, hair colour, dyeing and length of the tested samples to assess the independence from these variables or the association with them. Low, medium and high ranges of concentration were also estimated for each drug. 21.94% of the 2954 hair samples tested for phenylalkylamine derivatives were positive for one or more substances. 16.38% of the samples were positive for AP, 12.09% for MDMA and only 0.44% for MA. 6.60% of the tested samples were positive for AP/MDMA combination. A total of 3178 samples were tested for cannabinoids, resulting in 53.40% positive for THC and CBN. Simultaneous tests for phenylalkylamine derivatives and cannabinoids were performed in 2931 of the samples; 14.94% of them were positive for THC, CBN, and one or more amphetamines. According to the results from the statistical analysis, the use of THC and MDMA vary with age and gender among the Medico-Legal sector in an extended area of Spain, while the use of AP appears to be independent of these variables. On the other hand, the results of THC in hair could be influenced by the length of the tested segment; therefore, a consensus regarding the hair length between 3.0 and 5.5cm for THC testing should be reached.

Efficacy of single-dose antibiotic against early-onset pneumonia in comatose patients who are ventilated.

BACKGROUND: Comatose patients present a high risk of early-onset ventilator-associated pneumonia (EO-VAP) for which antibiotic prophylaxis has been proposed. Comatose patients were studied to evaluate the efficacy of a single-dose of antibiotic prophylaxis at intubation against EO-VAP. METHODS: A prospective cohort of comatose patients (Glasgow Coma Score ≤ 8) who were admitted in 2009-2010 and administered a single-dose of antibiotic within 4 h of intubation was compared with comatose patients (admitted ≥ 4 h after intubation in 2009-2010 or admitted in 2007-2008) who did not receive antibiotic prophylaxis. We analyzed the incidence of EO-VAP, late-onset VAP, and ventilator-associated tracheobronchitis in both groups. Propensity scores for receiving antibiotic prophylaxis were derived on the basis of patients' characteristics (eg, age and severity) to assess its impact on EO-VAP development. RESULTS: We included 129 patients (71 in the prophylaxis group and 58 in the control group). The global incidence of VAP and incidence of EO-VAP were lower in the prophylaxis group: 10.8 vs 28.4 episodes/1,000 days on mechanical ventilation (P = .015) and 4.4 vs 23.1 episodes/1,000 days on mechanical ventilation (P = .02), respectively. The incidence of late-onset VAP did not differ. The prophylaxis group tended toward lower incidence of ventilator-associated tracheobronchitis (15.5% vs 25.9%, P = .14). No differences in mortality were found between groups. The propensity-score regression analysis confirmed that a single dose of antibiotic prophylaxis was independently associated with lower incidence of EO-VAP (OR, 0.11; 95% CI, 0.02-0.58; P = .009). CONCLUSIONS: A single dose of antibiotic prophylaxis at intubation might lower the incidence of EO-VAP. However, a randomized clinical trial should be conducted to confirm our findings.

Nurses' detection of ineffective inspiratory efforts during mechanical ventilation.

UNLABELLED: BACKGROUND PATIENT: ventilator dyssynchrony is common and may influence patients' outcomes. Detection of such dyssynchronies relies on careful observation of patients and airway flow and pressure measurements. Given the shortage of specialists, critical care nurses could be trained to identify dyssynchronies. OBJECTIVE: To evaluate the accuracy of specifically trained critical care nurses in detecting ineffective inspiratory efforts during expiration. METHODS: We compared 2 nurses' evaluations of measurements from 1007 breaths in 8 patients with the evaluations of experienced critical care physicians. Sensitivity, specificity, positive predictive value, negative predictive value, and the Cohen κ for interobserver agreement were calculated. RESULTS: For the first nurse, sensitivity was 92.5%, specificity was 98.3%, positive predictive value was 95.4%, negative predictive value was 97.1%, and κ was 0.92 (95% CI, 0.89-0.94). For the second nurse, sensitivity was 98.5%, specificity was 84.7%, positive predictive value was 70.7%, negative predictive value was 99.3%, and κ was 0.74 (95% CI, 0.70-0.78). CONCLUSION: Specifically trained nurses can reliably detect ineffective inspiratory efforts during expiration.