Samia Madi-Jebara

Prophylactic ondansetron is effective in the treatment of nausea and vomiting but not on pruritus after cesarean delivery with intrathecal sufentanil-morphine

STUDY OBJECTIVES To assess the safety and efficacy of ondansetron for prevention of pruritus, nausea and vomiting after cesarean delivery with intrathecal sufentanil-morphine. DESIGN Randomized, double-blind, placebo-controlled study. SETTING Referral center, institutional practice. PATIENTS 100 nonbreastfeeding women undergoing elective cesarean delivery with sufentanil-morphine-bupivacaine anesthesia. INTERVENTIONS After the umbilical cord was clamped, patients in Group 1 received ondansetron 8 mg intravenously (IV) and patients in Group 2 received placebo. MEASUREMENTS Frequency and severity of postoperative (24-hour) pruritus, nausea and vomiting, surgical pain, and side effects related to ondansetron were recorded. MAIN RESULTS In the ondansetron group, 38 patients had pruritus (16 mild and 22 severe) and 9 patients had nausea and vomiting (5 mild and 4 severe). In the placebo group, 41 patients had pruritus (21 mild and 20 severe) and 29 patients had nausea and vomiting (9 mild and 15 severe). The frequency and severity of the nausea and vomiting episodes were significantly reduced in the ondansetron group. Pain scores were comparable between groups. No side effects related to ondansetron were reported. CONCLUSIONS Prophylactic IV ondansetron 8 mg is safe and effective in reducing the frequency and the severity of nausea and vomiting, but not pruritus, following cesarean delivery with intrathecal sufentanil-morphine.

Effect of vital capacity manoeuvres on arterial oxygenation in morbidly obese patients undergoing open bariatric surgery.

Background: Arterial oxygenation may be compromised in morbidly obese patients undergoing bariatric surgery. The aim of this study was to evaluate the effect of a vital capacity manoeuvre (VCM), followed by ventilation with positive end‐expiratory pressure (PEEP), on arterial oxygenation in morbidly obese patients undergoing open bariatric surgery. Methods: Fifty‐two morbidly obese patients (body mass index >40 kg m−2) undergoing open bariatric surgery were enrolled in this prospective and randomized study. Anaesthesia and surgical techniques were standardized. Patients were ventilated with a tidal volume of 10 mL kg−1 of ideal body weight, a mixture of oxygen and nitrous oxide (FiO2 = 40%) and respiratory rate was adjusted to maintain end‐tidal carbon dioxide at a level of 30–35 mmHg. After abdominal opening, patients in Group 1 had a PEEP of 8 cm H2O applied and patients in Group 2 had a VCM followed by PEEP of 8 cm H2O. This manoeuvre was defined as lung inflation by a positive inspiratory pressure of 40 cm H2O maintained for 15 s. PEEP was maintained until extubation in the two groups. Haemodynamics, ventilatory and arterial oxygenation parameters were measured at the following times: T0 = before application of VCM and/or PEEP, T1 = 5 min after VCM and/or PEEP and T2 = before abdominal closure. Results: Patients in the two groups were comparable regarding patient characteristics, surgical, haemodynamic and ventilatory parameters. In Group 1, arterial oxygen partial pressure (PaO2) and arterial haemoglobin oxygen saturation (SaO2) were significantly increased and alveolar‐arterial oxygen pressure gradient (A‐aDO2) decreased at T2 when compared with T0 and T1. In Group 2, PaO2 and SaO2 were significantly increased and A‐aDO2 decreased at T1 and T2 when compared with T0. Arterial oxygenation parameters at T1 and T2 were significantly improved in Group 2 when compared with Group 1. Conclusion: The addition of VCM to PEEP improves intraoperative arterial oxygenation in morbidly obese patients undergoing open bariatric surgery.

Postoperative oral amiodarone versus oral bisoprolol as prophylaxis against atrial fibrillation after coronary artery bypass graft surgery: A prospective randomized trial

BACKGROUND Postoperative atrial fibrillation (AF) occurs in up to 50% of patients undergoing coronary artery bypass (CABG) surgery and is associated with complications. Amiodarone and beta blockers are effective as prophylaxis for AF after CABG. The purpose of this study was to compare oral amiodarone versus oral bisoprolol for prevention of AF after CABG. METHODS In this randomized study, 200 patients admitted for elective CABG were given oral amiodarone (n=98 patients) or oral bisoprolol (n=102 patients) beginning 6 h after surgery. Amiodarone patients received 15 mg/Kg then 7 mg/Kg/day for one month. Bisoprolol patients received 2.5 mg then 2.5 mg bid indefinitely. RESULTS Postoperative AF occurred in 15.3% of the patients in the amiodarone group and 12.7% of the patients in the bisoprolol group (p=0.60). Maximal ventricular rate tended to be lower in the bisoprolol group (125+/-6 beats/min) compared with the amiodarone group (144+/-7 beats/min, p=.06). Preoperative beta blockage did not affect AF incidence in either study group. There was no difference between the 2 groups for the onset time of AF episodes, total AF duration, AF recurrence and postoperative length of hospital stay. No serious postoperative complications occurred in the two study groups. Two reversible low cardiac output cases occurred with bisoprolol. CONCLUSIONS Postoperative oral bisoprolol and amiodarone are equally effective for prophylaxis of AF after CABG. Treatment with bisoprolol resulted in a trend to lower ventricular response rate in AF cases. Both regimens were well tolerated.

Pulse Pressure Variation Predicts Fluid Responsiveness in Elderly Patients After Coronary Artery Bypass Graft Surgery

OBJECTIVE To assess the ability of pulse pressure variation to predict fluid responsiveness in mechanically ventilated elderly patients after coronary artery bypass graft surgery. DESIGN A prospective, interventional study. SETTING An academic, tertiary referral hospital. PARTICIPANTS Sixty patients >70 years old and mechanically ventilated after coronary artery bypass graft surgery. INTERVENTIONS Intravascular volume expansion using 6% hydroxyethyl starch solution, 7 mL/kg over 20 minutes. MEASUREMENTS AND MAIN RESULTS Heart rate, arterial blood pressure, pulse pressure variation, central venous pressure, pulmonary artery occlusion pressure, and stroke volume index were measured immediately before and after volume expansion. Fluid responsiveness was defined as an increase in stroke volume index ≥ 15% after volume expansion. Forty-one patients were fluid responders and 19 patients were nonresponders. In contrast to central venous pressure or pulmonary artery occlusion pressure, pulse pressure variation was higher in the responders than in the nonresponders (22 ± 6% v 9.3 ± 3%, p = 0.001) and correlated with the percent changes in the stroke volume index after volume expansion (r = 0.47, p = 0.001). The area under the receiver operating characteristic curve for pulse pressure variation was 0.85 (95% confidence interval 0.75-0.94). The threshold value of 11.5% allowed the discrimination between responders and nonresponders with a sensitivity of 80% and a specificity of 74%. CONCLUSIONS Pulse pressure variation is a reliable predictor of fluid responsiveness in mechanically ventilated elderly patients after coronary artery bypass graft surgery.

Can Femoral Artery Pressure Monitoring Be Used Routinely in Cardiac Surgery

OBJECTIVE The purpose of this study was to evaluate the safety of femoral arterial pressure monitoring in cardiac surgery. DESIGN Prospective, observational study. SETTING Cardiac surgery unit (CSU) in a university hospital. PARTICIPANTS Of a total of 2,350 consecutive patients scheduled for elective cardiac surgery with cardiopulmonary bypass, 2,264 patients with femoral artery pressure monitoring were included. INTERVENTIONS A femoral arterial catheter was inserted percutaneously before the induction of anesthesia. The catheter was withdrawn 40 to 96 hours after surgery. It was replaced by a radial artery catheter in patients staying for more than 4 days in the CSU or in case of pulse loss or lower limb ischemia. The catheter was removed and sent for cultures whenever it showed local changes, discharge, or if sepsis was suspected. MEASUREMENTS AND MAIN RESULTS Pain on insertion ranged from 0 to 20 mm on the 100-mm visual analog scale. Complications related to femoral artery cannulation were recorded. No cases of femoral artery thrombosis, lower extremity ischemia, or hematoma requiring surgery were noted. Small hematomas were observed in 3.3% of patients. The incidence of oozing was 2.1% after the insertion of the catheter and 4.9% after its removal. Three cases (0.13%) of serious bleeding occurred; 2 required surgery. Eight percent of catheter tips were sent for culture, and positive bacterial growth was recorded in 18.6% of them. Catheter-related blood stream infection occurred in 0.5% of the total patient population included. CONCLUSIONS Femoral artery pressure monitoring was associated with a low complication rate and, therefore, it can be used routinely in cardiac surgery.

The effect of low-dose intravenous ketamine on continuous intercostal analgesia following thoracotomy

Ketamine, a noncompetitive N-methyl-d-aspartate antagonist, provides analgesia and prevents chronic pain following thoracotomy. The study was aimed to assess the effect of intravenous low-dose ketamine on continuous intercostal nerve block analgesia following thoracotomy. The study was a prospective, randomized, double-blinded, and placebo-controlled clinical study, performed in a single university hospital. Sixty patients, undergoing elective lobectomy through an open posterolateral thoracotomy, were included. For postoperative pain, all patients received a continuous intercostal nerve block with bupivacaine plus intravenous paracetamol and ketoprofen. In addition, patients were randomized to have intravenous ketamine (0.1 mg/kg as a preincisional bolus followed by a continuous infusion of 0.05 mg/kg/h) in group 1 or intravenous placebo in group 2. Patients reporting a visual analog scale pain score at rest ≥40 mm received intravenous morphine sulfate as rescue analgesia. The following parameters were assessed every 6 hours for 3 postoperative days: Visual analog scale pain scores at rest and during coughing, requirement of rescue analgesia with morphine, Ramsay sedation scores and psychomimetic adverse effects. Both the groups were statistically comparable regarding visual analog scale pain scores at rest (P=0.75) and during coughing (P=0.70), number of morphine deliveries (P=0.17), cumulative dose of rescue morphine (P=0.2), sedation scores (P=0.4), and psychomimetic adverse effects (P=0.09). Intravenous low-dose ketamine, when combined with continuous intercostal nerve block, did not decrease acute pain scores and supplemental morphine consumption following thoracotomy.

Is prompt exploratory laparotomy the best attitude for mesenteric ischemia after cardiac surgery

Mesenteric ischemia following cardiac surgery is a life-threatening complication. Early identification of patients may help optimizing management and improving outcome. Between January 2000 and July 2007, surgical exploration was realized when mesenteric ischemia was suspected after coronary-artery bypass grafts (CABG). Patients were divided in two groups according to diagnosis confirmation upon laparotomy. Peri-operative predictors of complication and death were analyzed. Of 1634 consecutive patients, 13 (0.8%) developed acute abdomen with suspicion of mesenteric ischemia. Seven (0.4%) underwent resection for ischemic lesions (group 1), of whom two were during a second look laparotomy. The other six patients had normal bowel (group 2). Both groups were comparable according to preoperative status, clinical signs, biological and radiological findings. Delays to laparotomy were 13.7+/-19.0 and 51.4+/-29.0 h in group 1 and 2, respectively (P=0.02). Mortality rates were 46.1% (6/13) overall, 42.8% for group 1 and 50% for group 2. All deaths occurred within the first nine postoperative days. Mesenteric ischemia following CABG is a fatal complication in almost half the cases. Diagnostic tools and timely laparotomy still need to be optimized. Low threshold-based strategy for prompt surgical intervention is efficient for both diagnosis and treatment.

Correlation between central venous oxygen saturation and oxygen delivery changes following fluid therapy

Background: The rationale for using central venous oxygen saturation (ScvO2) in various clinical scenarios is that it reflects the balance between oxygen delivery (DO2) and demands. In this study, we evaluated the correlation between ScvO2 and DO2 changes (ΔDo2, ΔScvO2) in patients receiving fluid therapy following coronary surgery. We also correlated the changes of mean arterial pressure (ΔMAP) and central venous pressure (ΔCVP), with ΔDO2.

Ondansetron for prevention of intrathecal opioids-induced pruritus, nausea and vomiting after cesarean delivery.

We have read with interest the article by Charuluxananan et al. (1) that compares the effectiveness of nalbuphine and ondansetron in the prevention of intrathecal morphine-induced pruritus after cesarean delivery. The authors found that prophylactic nalbuphine and ondansetron were both effective in reducing pruritus but not nausea and vomiting induced by 0.2 mg of intrathecal morphine. In a similar study (2), we assessed the efficacy of ondansetron for the prevention of pruritus, nausea, and vomiting induced by intrathecal sufentanil-morphine in 100 patients undergoing cesarean delivery. Doses of drugs used were 8 mg of ondansetron, 0.1 mg of morphine, and 2.5 g of sufentanil. The incidence of nausea and vomiting, in this study, was significantly reduced in the treatment group when compared with the placebo group (18% vs 48%; P 0.001). However, the incidence of pruritus was not decreased in the treatment group when compared with the placebo group (76% versus 82%; P 0.46). These results are not in agreement with the data reported by Charuluxananan et al. Failure of ondansetron to prevent pruritus in our study may be explained by the fact that sufentanil—which is a highly lipophilic opioid with a quick onset of action—was added to intrathecal morphine. The serotonin receptors in the spinal cord were probably activated by sufentanil before they were blocked by ondansetron. Furthermore, and because the incidence of nausea and vomiting following intrathecal opioids is dosedependent (3), the effectiveness of ondansetron in our study could be related to the low dose (0.1 mg) of the intrathecally administrated morphine as compared with the higher dose (0.2 mg) used by Charuluxananan et al. In conclusion, prophylactic ondansetron decreases the incidence of intrathecal opioid-induced pruritus, nausea, and vomiting after cesarean delivery. However, ondansetron may not be effective when highly lipophilic opioids or increased doses of morphine are administrated.

Accuracy of radial arterial pressure measurement during surgery under controlled hypotension

Background: Radial arterial pressure underestimates the pressure in the aorta in several clinical situations. A central‐to‐radial pressure gradient was attributed to intense vasodilation. The aim of this study was to evaluate the accuracy of radial pressure monitoring during controlled hypotension achieved with profound arterial vasodilation.