Micro- and macrocirculatory effects of norepinephrine on anaesthesia-induced hypotension: a prospective preliminary study.

BACKGROUND: Intraoperative arterial hypotension (IOH) leads to increased postoperative morbidity. Norepinephrine is often use to treat IOH. The question regarding the mode of administration in either a bolus or continuous infusion remains unanswered. The aim of the present study was to describe and compare the effects on macrocirculation and microcirculation of a bolus and a continuous infusion of norepinephrine to treat IOH. METHODS: We conducted a prospective observational study with adult patients who underwent neurosurgery. Patients with invasive arterial blood pressure and cardiac output (CO) monitoring were screened for inclusion. All patients underwent microcirculation monitoring by video-capillaroscopy, laser doppler, near-infrared spectroscopy technology, and tissular CO2. In case of IOH, the patient could receive either a bolus of 10 µg or a continuous infusion of 200 µg/h of norepinephrine. Time analysis for comparison between bolus and continuous infusion were at peak of MAP. The primary outcome was MFI by videocapillaroscopy. RESULTS: Thirty-five patients were included, with 41 boluses and 33 continuous infusion. Bolus and continuous infusion induced an maximal increase in mean arterial pressure of +30[20-45] and +23[12-34] %, respectively (P=0,07). For macrocirculatory parameters, continuous infusion was associated with a smaller decrease in CO and stroke volume (p<0.05). For microcirculatory parameters, microvascular flow index (-0,1 vs. + 0,3, p=0,03), perfusion index (-12 vs. +12%, p=0,008), total vessel density (-0,2 vs. +2,3 mm2/mm2, p=0,002), showed significant opposite variations with bolus and continuous infusion, respectively. CONCLUSIONS: These results on macro and microcirculation enlighten the potential benefits of a continuous infusion of norepinephrine rather than a bolus to treat anaesthesia-induced hypotension. TRIAL REGISTRATION: (NOR-PHARM: 1-17-42 Clinical Trials: NCT03454204), 05/03/2018.

Swallowing disorders as a predictor of unsuccessful extubation: a clinical evaluation.

BACKGROUND: Unsuccessful extubation may be due to swallowing dysfunction that causes airway obstruction and impairs patients' ability to cough and expectorate. OBJECTIVE: To determine whether swallowing assessment before extubation is helpful in predicting unsuccessful extubation due to airway secretions. METHODS: This prospective study included all patients intubated orotracheally for more than 6 days. Before extubation, 3 tests designed to assess (1) cervical, oral, labial, and lingual motility; (2) gag reflex; and (3) swallowing were used at the bedside. Causes of reintubation were identified, and their relationship to patients' swallowing function before extubation was evaluated. RESULTS: Sixty-two patients were enrolled. Data on 55 patients reintubated for swallowing dysfunction were analyzed. Nine patients were reintubated because of obstruction related to upper airway secretions. Evaluation before extubation enabled prediction of 7 of those 9 unsuccessful extubations. Among the 23 patients with central nervous system disease, 3 of 4 unsuccessful extubations were predicted. According to a multivariate logistic regression model, motility and swallowing were independent predictors of unsuccessful extubation (area under receiver-operating-characteristic curve, 80%). The gag reflex was the only significant predictor of the ability to cough (area under curve, 73%) and excessive pulmonary secretion (area under curve, 67%). Swallowing was an independent predictor of the need for suctioning (area under curve, 78%). CONCLUSIONS: Using simple bedside tests to evaluate swallowing before extubation is helpful when deciding whether to extubate patients who have been intubated for more than 6 days. Involvement of nurses in these decisions would improve patients' management.

Survey of the use of catecholamines by French physicians.

OBJECTIVE: The objective of the study was to perform a descriptive approach of the current use of catecholamines by French physicians. DESIGN: A questionnaire of 12 questions with 4 items established by a group of French intensivists. POPULATION: French physicians from 433 departments working in the following practicing areas: intensive care unit (ICU), emergency department, and pre-hospital setting. MEASUREMENTS: Responding physicians were asked about the catecholamine that they would select in various clinical settings. RESULTS: The response rate was 82%. Of the responding physicians, 277 (78%) worked in an ICU, 28 (8%) in an emergency department, and 21 (6%) in a pre-hospital setting. Dobutamine was chosen for patients with cardiogenic shock by 90% of the respondents. Norepinephrine was the first choice agent as vasopressor in patients with septic shock in 52% of the cases. Dopamine was selected in a clinical setting requiring an optimization of regional blood flow, as in the concept of high-risk surgical patients. Dopexamine was used as a second or third choice agent to improve regional blood flow and cardiac output. The indications of epinephrine for anaphylactic shock and cardio-circulatory arrest were obvious for more than 90% of responding physicians. CONCLUSION: A lack of standardization appears in the use of catecholamines by French physicians, particularly for improvement of regional circulation and management of high-risk surgical patients. Guidelines that define the place of each catecholamine in these settings are required to improve the quality of prescription.