Dynamic arterial elastance measured by uncalibrated pulse contour analysis predicts arterial-pressure response to a decrease in norepinephrine.

BACKGROUND: Dynamic arterial elastance (Eadyn) has been proposed as an indicator of vascular tone that predicts the decrease in arterial pressure in response to changes in norepinephrine (NE). The purpose of this study was to determine whether Eadyn measured by uncalibrated pulse contour analysis (UPCA) can predict a decrease in arterial pressure when the NE dosage is decreased. METHODS: We conducted a prospective study in a university hospital intensive care unit. Patients with vasoplegic syndrome for whom the intensive care physician planned to decrease the NE dosage were included. Haemodynamic and UPCA (VolumeView and FloTrac; Edwards Lifesciences, Irvine, CA, USA) values were obtained before and after decreasing the NE dosage. Responders were defined by a >10% decrease in mean arterial pressure (MAP). RESULTS: Of 35 patients included, 11 (31%) were pressure responders with a median decrease of 13%. Eadyn was correlated to systolic arterial pressure (SAP) (r=0.255; P=0.033), diastolic arterial pressure (r=0.271; P=0.024), MAP (r=0.310; P=0.009), heart rate (r=0.543; P=0.0001), and transthoracic echography cardiac output (r=0.264; P=0.024). Baseline Eadyn was correlated with MAP changes (r=0.394; P=0.019) and SAP changes (r=0.431; P=0.009). Eadyn predicted the decrease in arterial pressure with an area under the receiver-operating-characteristic curve of 0.84 (95% confidence interval: 0.70-0.97). The best cut-off was 0.90. CONCLUSIONS: The present study confirms the ability of Eadyn measured by UPCA to predict an arterial pressure response to a decrease in NE. Eadyn may constitute an easy-to-use functional approach to arterial tone assessment regardless of the monitor used to measure its determinant. CLINICAL TRIAL REGISTRATION: DRCIT95.

Management of breech and twin labor during registrarship: A two-year prospective, observational study.

INTRODUCTION: Breech presentation and twin pregnancy are regarded as stressful situations for medical staff. This stress is often associated with an increased likelihood of intervention during labor - especially when the on-shift obstetrician lacks experience. MATERIAL AND METHODS: We performed a 2-year prospective, observational study of cesarean section (CSDs) and assisted vaginal (AVDs) deliveries in a tertiary maternity unit for attempted vaginal deliveries of breech presentations and twin pregnancies. The obstetric management decisions taken by a group of four registrars were compared with those taken by a group of 11 experienced obstetricians. Changes over time in practice were also monitored. RESULTS: Registrars managed 66 and 52 breech presentations and twin pregnancies respectively (30 and 27 in the experienced group). Groups' neonatal outcomes were similar. There were no intergroup differences in proportions of CSDs for either breech presentations (25 [37.5%] vs. 15 [50%] in the registrar and experienced groups, respectively; P=0.26) or twin pregnancies (11 [21.1%] vs. 6 [22.2%], respectively; P=0.91) or in proportion of AVDs for twin pregnancies (41 [78.8%] vs. 21 [77.8%], respectively; P=0.91). Proportions of CSDs for breech presentation and AVDs for twin pregnancies did not change over time in either group. However, proportion of CSDs for twin pregnancies increased over time in the registrar group (P=0.004). DISCUSSION: Well-trained registrars appeared to have acquired the skills required to safely manage an obstetric ward; this pleads to maintain clinical practice during residency to preserve low CSD and AVD rates.

Respiratory stroke volume variation assessed by oesophageal Doppler monitoring predicts fluid responsiveness during laparoscopy.

BACKGROUND: This study was designed to assess the ability of the stroke volume respiratory variation (ΔrespSV) determined by oesophageal Doppler monitoring (ODM) to predict the response to volume expansion (VE) during pneumoperitoneum. The predictive value of ΔrespSV was evaluated according to the concept of the 'grey zone'. METHODS: Patients operated on laparoscopy and monitored by ODM were prospectively included. The exclusion criteria were frequent ectopic beats or preoperative arrhythmia, right ventricular failure, and spontaneous breathing. Haemodynamic parameters and oesophageal Doppler indices [stroke volume (SV), peak velocity (PV), cardiac output (CO), corrected flow time (FTc), respiratory variation of PV (ΔrespPV) and SV (ΔrespSV)] were collected before and after VE. Responders were defined as a ≥15% increase in SV after VE. RESULTS: Thirty-eight (64%) of the 59 patients were responders. A cut-off of >14% ΔrespSV predicted fluid responsiveness with an area under the ROC curve (AUC) of 0.92 [95% confidence interval (CI): 0.82-0.98, P<0.0001]. The grey zone of ΔrespSV ranged between 13 and 15%. With an AUC of 0.71 (95% CI: 0.56-0.83, P=0.005), ΔrespPV fairly accurately predicted fluid responsiveness. FTc was unable to accurately predict fluid responsiveness. CONCLUSIONS: ΔrespSV and ΔrespPV predicted fluid responsiveness during laparoscopy under strict physiological conditions. FTc was not predictive of fluid responsiveness during laparoscopy.

[Unanticipated difficult extubation]. / Extubation difficile imprévue.

Complications at extubation remain an important risk factor in anaesthesia. Airway related complications at extubation are relatively frequent but are usually dealt with by simple basic measures. We report a new case of respiratory complications associated with tracheal extubation in a 59-year-old woman. Her medical history included obesity, no criteria difficult intubation and no adverse events during her previous anesthetic procedures. At the end of surgery, immediately after extubation, the patient developed respiratory distress requiring reintubation. A second extubation performed in postoperative recovery room was complicated by a new respiratory distress with reintubation. The patient was then admitted to the ICU. The examination on admission was unremarkable. Chest X-ray and a chest CT scan were performed in search of an etiology. Both tests showed a large thyroid "goitre plongeant" (plunging goiter) and compressive. In the suites, a thyroidectomy was performed with excision of a large cervical plunging goiter para- and retropharyngeal bilateral chest, allowing extubation successfully. The postoperative course was uneventful.

Ability of stroke volume variation measured by oesophageal Doppler monitoring to predict fluid responsiveness during surgery.

BACKGROUND: The objective of this study was to test whether non-invasive assessment of respiratory stroke volume variation (ΔrespSV) by oesophageal Doppler monitoring (ODM) can predict fluid responsiveness during surgery in a mixed population. The predictive value of ΔrespSV was evaluated using a grey zone approach. METHODS: Ninety patients monitored using ODM who required i.v. fluids to expand their circulating volume during surgery under general anaesthesia were studied. Patients with a preoperative arrhythmia, right ventricular failure, frequent ectopic beats, or breathing spontaneously were excluded. Haemodynamic variables and oesophageal Doppler indices [peak velocity (PV), stroke volume (SV), corrected flow time (FTc), cardiac output (CO), ΔrespSV, and respiratory variation of PV (ΔrespPV)] were measured before and after fluid expansion. Responders were defined by a >15% increase in SV after infusion of 500 ml crystalloid solution. RESULTS: SV was increased by ≥15% after 500 ml crystalloid infusion in 53 (59%) of the 90 patients. ΔrespSV predicted fluid responsiveness with an area under the receiver-operating characteristic (AUC) curve of 0.91 [95% confidence interval (95% CI): 0.85-0.97, P<0.0001]. The optimal ΔrespSV cut-off was 14.4% (95% CI: 14.3-14.5%). The grey zone approach identified 12 patients (14%) with a range of ΔrespSV values between 14% and 15%. FTc was not predictive of fluid responsiveness (AUC 0.49, 95% CI: 0.37-0.62, P=0.84). CONCLUSIONS: ΔrespSV predicted fluid responsiveness accurately during surgery over a ΔrespSV range between 14% and 15%. In contrast, FTc did not predict fluid responsiveness.