Variable versus conventional lung protective mechanical ventilation during open abdominal surgery (PROVAR): a randomised controlled trial.

BACKGROUND: Experimental studies showed that controlled variable ventilation (CVV) yielded better pulmonary function compared to non-variable ventilation (CNV) in injured lungs. We hypothesized that CVV improves intraoperative and postoperative respiratory function in patients undergoing open abdominal surgery. METHODS: Fifty patients planned for open abdominal surgery lasting >3 h were randomly assigned to receive either CVV or CNV. Mean tidal volumes and PEEP were set at 8 ml kg-1 (predicted body weight) and 5 cm H2O, respectively. In CVV, tidal volumes varied randomly, following a normal distribution, on a breath-by-breath basis. The primary endpoint was the forced vital capacity (FVC) on postoperative Day 1. Secondary endpoints were oxygenation, non-aerated lung volume, distribution of ventilation, and pulmonary and extrapulmonary complications until postoperative Day 5. RESULTS: FVC did not differ significantly between CVV and CNV on postoperative Day 1, 61.5 (standard deviation 22.1) % vs 61.9 (23.6) %, respectively; mean [95% confidence interval (CI)] difference, -0.4 (-13.2-14.0), P=0.95. Intraoperatively, CVV did not result in improved respiratory function, haemodynamics, or redistribution of ventilation compared to CNV. Postoperatively, FVC, forced expiratory volume at the first second (FEV1), and FEV1/FVC deteriorated, while atelectasis volume and plasma levels of interleukin-6 and interleukin-8 increased, but values did not differ between groups. The incidence of postoperative pulmonary and extrapulmonary complications was comparable in CVV and CNV. CONCLUSIONS: In patients undergoing open abdominal surgery, CVV did not improve intraoperative and postoperative respiratory function compared with CNV. CLINICAL TRIAL REGISTRATION: NCT 01683578.

Verbal memory impairment in congestive heart failure.

Cognitive dysfunction, mainly memory impairment, characterizes congestive heart failure (CHF). Aim of this study was to verify whether: (1) CHF has differential effects on primary and secondary memory; (2) memory dysfunction can be diagnosed by a screening instrument. In a multicenter study we enrolled 369 patients with stable CHF who underwent a structured assessment of verbal memory mechanisms and selected cognitive functions. Performance on some verbal memory indexes (Recency, Rey's immediate and delayed recall, Learning efficiency) progressively decreased from II to IV New York Heart Association (NYHA) class. Rate of forgetting was uniformly high across NYHA classes II-IV. Verbal memory indexes were highly correlated with most nonverbal scores. The Mini Mental State Examination (MMSE) had poor sensitivity and specificity versus primary or secondary verbal memory dysfunction. Therefore, a deficit of both primary and secondary memory is relatively common in CHF but cannot be accurately recognized by a screening neuropsychological test.

Effects of pneumoperitoneum and reverse Trendelenburg position on cardiopulmonary function in morbidly obese patients receiving laparoscopic gastric banding.

We prospectively evaluated the effects of pneumoperitoneum and reverse Trendelenburg position on cardiopulmonary function in 20 ASA physical status II-III morbidly obese patients (body mass index > 35 kg m(-2)) undergoing laparoscopic gastric banding. After general anaesthesia was induced, patients' lungs were ventilated using intermittent positive pressure ventilation (at measurement times, the following parameters were used: tidal volume 12 mL kg(-1) ideal body weight, respiratory rate of 12 bpm, an inspiratory to expiratory time ratio of 1:2). Haemodynamic variables, blood gas parameters, and lung/chest compliance were recorded: in the supine position, after induction of general anaesthesia (T0, baseline) and induction of pneumoperitoneum (T1); after placing the patient in a 25 degree reverse Trendelenburg position (T2); during the surgical time (T3); before deflating the abdomen (T4); after pneumoperitoneum resolution (T5), and before the end of anaesthesia, with the patient supine (T6). The PaO2, PaO2/FiO2 ratio, and lung/chest compliance decreased during the study. After the pneumoperitoneum had been resolved, lung/chest compliance but not oxygenation parameters returned to baseline values. The arterial to end-tidal CO2 tension difference progressively increased from 0.38+/-0.3 kPa (2.85+/-2.25 mmHg) (T0) to 0.63+/-0.3 kPa (4.73+/-2.25 mmHg) (T6). In morbidly obese patients, undergoing laparoscopic gastric banding, a CO2 pneumoperitoneum markedly affected gas exchange and lung/chest compliance, while positioning the patient in a 25 degree reverse Trendelenburg position had no beneficial effects.

A double-blind comparison of ropivacaine, bupivacaine, and mepivacaine during sciatic and femoral nerve blockade.

UNLABELLED: No study has evaluated the efficacy of ropivacaine in peripheral nerve block of the lower extremity. The purpose of this prospective, randomized, double-blind study was to compare ropivacaine, bupivacaine, and mepivacaine during combined sciatic-femoral nerve block. Forty-five ASA physical status I or II patients scheduled for elective hallux valgus repair with thigh tourniquet were randomized to receive combined sciatic-femoral block with 0.75% ropivacaine (ROPI, n = 15), 0.5% bupivacaine (BUPI, n = 15), and 2% mepivacaine (MEPI, n = 15). Time required for onset of sensory and motor block on the operated limb (readiness for surgery) and resolution of motor block, as well as onset of postsurgical pain and time of first analgesic requirement, were recorded. The three groups were similar with regard to demographic variables, duration of surgery, and measured visual analog pain scores. Onset of sensory and motor blockade was similar in Groups ROPI and MEPI and significantly shorter than in Group BUPI (P = 0.002 and P = 0.001, respectively). Resolution of motor block occurred later in Groups ROPI and BUPI than in Group MEPI (P = 0.005 and P = 0.0001, respectively). Duration of postoperative analgesia was significantly longer in Groups ROPI (670+/-227 min) and BUPI (880+/-312 min) compared with Group MEPI (251+/-47 min) (P = 0.0001), with a significant decrease in postoperative pain medication requirements (P < 0.05). We conclude that for sciatic-femoral nerve block, 0.75% ropivacaine has an onset similar to that of 2% mepivacaine and a duration of postoperative analgesia between that of 0.5% bupivacaine and 2% mepivacaine. IMPLICATIONS: Quick onset of block with prolonged postoperative analgesia is an important goal in peripheral nerve blockade. We evaluated the clinical properties of 0.5% bupivacaine, 2% mepivacaine, and 0.75% ropivacaine for sciatic-femoral nerve block and demonstrated that ropivacaine has an onset similar to that of mepivacaine but allows for postoperative analgesia between that of bupivacaine and mepivacaine.

A clinical comparison between needle-through-needle and double-segment techniques for combined spinal and epidural anesthesia.

BACKGROUND AND OBJECTIVES: The goal of the present investigation was to compare the double-segment and the needle-through-needle techniques for combined spinal and epidural anesthesia (CSE) in a prospective, randomized, blinded study. METHODS: With Ethical Committee approval and patient's consent, 120 patients were randomized to receive CSE by the needle-through-needle (SST; n=60) or the double-segment technique (DST; n=60). A blind observer measured the time required from skin disinfection to readiness for surgery (loss of pinprick sensation up to T10), failure of dural puncture, need for epidural top-up before surgery, patient acceptance, and occurrence of complications. RESULTS: No neurologic complications were observed in either group. Time to readiness for surgery was 22.7+/-8.2 minutes in the SST group and 29.8+/-8.31 minutes in the DST one (P < .001). Dural puncture was unsuccessful in three patients in the SST group (5%) and in one patient in the DST group (1.6%) (ns); inadequate spread of spinal anesthesia was observed in five patients in the SST group (8.3%) and in eight patients in the DST group (13.3%) (ns). No difference in the incidence of hypotension, postdural puncture headache, and back pain was observed between the two groups. Acceptance of anesthetic procedure was better in the SST (85%) than in the DST group (66.6%) (P < .05). CONCLUSIONS: The needle-through-needle technique for CSE requires less time, has no greater failure rate, and results in greater patient satisfaction than the double-segment technique. The use of a spinal needle with an adjustable locking mechanism and protruding up to 15 mm beyond the Tuohy needle improved successful spinal block in the needle-through-needle technique compared with previous reports.

Femoral Arterial Hemostasis using the Angio-Sealª System after Coronary and Vascular Percutaneous Angioplasty and Stenting.

The procedures of left cardiac catheterization and revascularization by angioplasty are associated with a substantial risk of hemorrhagic complications. This risk increases clearly in patients with an intravascular stent who require early high doses of anticoagulant therapy. The first purpose of our study was to evaluate the effectiveness of a mechanical system of femoral hemostasis (Angio-Sealª, Sherwood Davis & Geck, St. Louis, Missouri) deployed in a group of 411 consecutive patients (302 males, 109 females, mean age 59 +/- 15) who successfully underwent percutaneous angioplasty (PA) and application of an intravascular stent (378 coronary, 33 vascular). The arterial closure system consists of a small absorbable anchor and a collagen pad connected to a suture thread which, at the end of the procedure, is positioned by percutaneous introduction at the site of the femoral puncture. All the patients studied received long-term platelet anti-aggregant therapy (ticlopidine 500 mg/day and ASA 150 mg/day) for 3Ð4 days before and for one month after the procedure, and an anticoagulant regimen of heparin sodium administered via intravenous bolus (10,000 IU) during the procedure, followed by subcutaneous heparin calcium (12,500 IU/day) for 21 days. Thirteen patients were treated intravenously with 10 mg abciximab and seven received pre-procedure coumadin. The ACT when the hemostasis system was positioned was 355 +/- 43 seconds. Successful hemostasis was reached in more than 95% of the patients (394/411 pts., 95.86%). In 17 (4.14%) of the 411 patients studied, the system failed; nine (2.19%) of these were attributed by the operator to a failure of the positioning device procedure, and the remaining 8 (1.95%) were attributed to a malfunction of the system. Overall complications were observed in 23/411 (5.6%) of the patients (pts) studied; eighteen were minor non-surgical hemorrhagic complications (bleeding and/or hematoma) which occurred primarily in the first 4 hours. In 4 cases (1%) vascular surgery was necessary for femoral pseudoaneurysm repair (2 pts) and femoral hematoma (2 pts). One patient (0.24%) complained of severe claudication related to a severe stenosis in the femoral artery caused by a malpositioning of the anchor. This patient was successfully treated with balloon angioplasty and stenting of the femoral artery. The average time to early mobilization was 9 hours, and all the patients without complications were completely mobile within 12 hours after the procedure; 380/411 (92.46%) of the patients were discharged 18Ð24 hours after percutaneous angioplasty. The second purpose of our study was to compare data from 411 consecutive patients treated with the Angio-Sealª device after coronary and vascular angioplasty and stenting (Angio-Seal group), to a group of 387 consecutive patients where the femoral arterial hemostasis was obtained using manual compression after coronary angioplasty and stenting (manual compression group). We found significant differences (p < 0.01) in the most important elements concerning general patient management after the interventional procedure, with excellent improvements using the Angio-Seal device, including: successful hemostasis (95.86% vs. 88.37%); reduction of non-surgical hematomas (1.22% vs. 4.65%); reduction of surgical hematomas (0.49% vs. 2.84%); mobilization time (9 +/- 3 hours vs. 19 +/- 8 hours); and discharge within 18Ð24 hours (92.46% vs. 0.00%).

[Effects of filtering techniques on time-domain analysis of signal-averaged ECG after acute myocardial infarction: a multicenter study, GISS-3 arrhythmia sub-project]. / Effetti delle techniche di filtraggio sull'analisi nel dominio del tempo del signal-averaged ecg dopo infarto miocardico acuto: studio multicentrico, GISSI-3 sottoprogetto aritmie. GISSI-3 Sottoprogetto Aritmie (Elenco dei Centri in ultima pagina).

AIM OF THE STUDY: To evaluate the influence of different filtering techniques on the measurement of ventricular late potentials (VLP) the Sottoprogetto Aritmie of GISSI-3 collected signal-averaged ECG (SAECG) from 647 patients. METHODS: Data were recorded after myocardial infarction (10 +/- 4 days) in 20 Italian Coronary Units. Three main filtering algorithms were used in the different commercial devices: Bidirectional Filter (ART, Aerotel, Fidelity Medical) (BF: 340 Patients), Spectral Filter (Marquette) (SF: 258 Patients) and Del Mar Filter (Del Mar Avionics) (DF: 49 Patients). QRS duration (QRSD), low amplitude signal duration (LAS40) and root mean-square-voltage (RMS40), were measured with various filters set at 40-250 Hz high and low pass frequencies. RESULTS: After correction for clinical variables the measurements of VLP in the three different groups were different. QRSD value obtained by BF (100.6 +/- 13 ms) was shorter than that obtained by SF (109.1 +/- 12 ms). No differences were found in LAS40 and RMS40 values between SF and BF, while DF gave longer LAS40 and lower RMS40 than SF and BF. Residual noise was lower in BF (0.3 +/- 0.1 muV). than in SF and DF (0.5 +/- 0.1 muV). Applying standard criteria DF gave a higher prevalence of VLP (48.9%) than BF (23.8%) and SF (19%) groups. CONCLUSIONS: This study demonstrates that the use of different filters produces discordant result on VLP measurements. For correct application of SAECG analysis in risk stratification after myocardial infarction, normal and abnormal values must be specifically established for the different filter techniques.