The effect of pulsatile versus non-pulsatile flow during cardiopulmonary bypass on cerebral oxygenation: A randomized trial.

BACKGROUND: The present study aims to compare regional oxygen supply determined by Near-Infrared Spectroscopy in the course of pulsatile perfusion with non-pulsatile perfusion during cardiopulmonary bypass in patients undergoing valvular heart surgery. METHODS: In this prospective randomized single-blinded trial, we enrolled adult subjects aged 18-65 years scheduled for elective valvular heart repair/replacement surgery with non-stenotic carotid arteries, employing a consecutive sampling method. Eligible patients were then randomly assigned in a 1:1 ratio to pulsatile or non-pulsatile perfusion during aortic cross-clamp. The primary outcome was regional cerebral oxygenation monitored by Near-Infrared Spectroscopy in each group. RESULTS: Seventy patients were randomly assigned, and each group comprised 35 patients. Mean age was 46.8 and 46.5 years in pulsatile and non-pulsatile groups, respectively. There were no significant between-group differences in regional cerebral oxygen saturation at different time points of cardiopulmonary bypass (p-value for analysis of variance repeated measures: 0.923 and 0.223 for left and right hemispheres, respectively). Moreover, no significant differences in regional cerebral oxygen saturation levels from baseline between pulsatile and non-pulsatile groups at all desired time points for the left (p = 0.51) and right (p = 0.22) hemispheres of the brain were detected. CONCLUSION: Pulsatile perfusion during cardiopulmonary bypass does not offer superior regional cerebral oxygenation measured by Near-Infrared Spectroscopy than non-pulsatile perfusion during cardiopulmonary bypass. Nonetheless, the efficacy of pulsatile flow in the subgroup of patients in whom cerebral blood flow is impaired due to carotid artery stenosis needs to be explored and evaluated by this method in future studies.

Modified translaryngeal tracheostomy for ventilator-dependent cardiac patients: A pilot of nonrandomized study.

INTRODUCTION: A significant proportion of ventilator-dependent cardiac patients need tracheostomy during intensive care unit (ICU) stay. Three different methods including traditional (surgical), percutaneous dilatation tracheostomy, translaryngeal tracheostomy (TLT), and classical Fantoni method have been developed. In this study, modified translaryngeal tracheostomy (MTLT) has been introduced to reduce and correct the technical difficulty of classical TLT through the larynx. MATERIALS AND METHODS: The patients hospitalized because of cardiac diseases whose stay in ICU and coronary care unit lasted longer than 3 weeks, and were consulted and advised for elective tracheostomy. Afterwards, MTLT was performed for all patients (the new method). RESULTS: From the 159 patients, 64.2% were women. The mean age was 65.25 ±â€Š14.35 years. There was no considerable hemorrhage (bleeding >5-10 mL). The mean values of arterial oxygen pressure, oxygen saturation, heart rate, systolic blood pressure, and a peak airway pressure before and after MTLT had a significant improvement (P < .05), which reflects a better hemodynamic state after tracheostomy. All of the tracheostomies (MTLT) were successful and without any complications. There was no considerable bleeding despite the high international normalized ratio levels. CONCLUSIONS: Unlike the classical Fantoni method, this study indicates that using a new improved method of tracheostomy through larynx did not impose any difficulty on retrograde passage of guide wire and this procedure could be safely conducted on patients with coagulation disorders.

Suprasternal innominate artery cannulation for reoperative aortic surgery: a technical note.

Suprasternal cannulation of the innominate artery in aortic reoperations may be useful in specific situations. Over a period of 3.5 years, 9 patients (6 males, average age = 49.2 ± 16.1 years) underwent suprasternal cannulation prior to resternotomy. Cannulation was performed using a side graft. All operations were successfully completed. Two patients died after surgery because of coagulopathy and multiorgan failure. There were no complications related to access or technique, and no site complications were detected during follow-up. Suprasternal cannulation of the innominate artery may play a role in selected reoperations.

Intravenous patient-controlled remifentanil versus paracetamol in post-operative pain management in patients undergoing coronary artery bypass graft surgery.

BACKGROUND: Pain management after cardiac surgery has been based on parenteral long-acting opioids such as morphine. The other alternatives are paracetamol and remifentanil. OBJECTIVES: In this prospective, double-blind, randomized study, we compared the efficacy of intravenous patient-controlled analgesia (IV-PCA) paracetamol and remifentanil for post cardiac surgery pain relief. MATERIALS AND METHODS: One-hundred patients scheduled for elective coronary artery bypass grafting from May to October 2011, were randomized into two groups after the surgery. For the first group (group R, n = 50, with mean age of 58.16 ± 11.80), the IV-PCA protocol was remifentanil infusion 100 µg/h; bolus of 25 µg and lockout time of 15 minutes. In the second group (group P, n = 50, with mean age of 53.8 ± 15.08), patients received paracetamol 15 mg/kg as a bolus at the end of surgery and then IV-PCA protocol was 100 µg/h, bolus of 25 µg; and lockout time of 15 minutes. Pain was assessed with visual analog scale score (VAS) in the first 24 hours after surgery for seven times. RESULTS: The trend of pain scores did not have any significantly difference between group R and group P except for hour 8 and hour 18 after surgery that VAS was significantly lower in group P than group R (P = 0.031, P = 0.023, respectively). Respiratory rate (RR) was also statistically lower in group R comparing to group P in all seven evaluating times. The groups were similar in terms of hemodynamic, ABG results (except for PaO2, which was significantly lower in group R than group P at 6 evaluating times), intubation time, renal function tests, and incidences of atelectasis, myocardial infarction or adverse effects. CONCLUSIONS: Both PCA techniques provided effective pain scores (< 3) after cardiac surgery; but generally, PCA-paracetamol infusion has a better analgesic effect.

The Effects of Positive Airway Pressure Ventilation during Cardiopulmonary Bypass on Pulmonary Function Following Open Heart Surgery.

BACKGROUND: Intrapulmonary shunt as a result of atelectasis following cardiac surgeries is an important and common postoperative complication that results into pulmonary dysfunction typically lasting more than a week following surgery. Different methods have been provided to prevent these complications. OBJECTIVES: In order to prevent postoperative pulmonary complications, investigation of the effectiveness of continuous positive airway pressure (CPAP) and intermittent mandatory ventilation (IMV) during cardiopulmonary bypass (CPB) in patients undergoing coronary artery bypass grafting (CABG). MATERIALS AND METHODS: In this prospective interventional study, 300 patients, candidate for elective CABG (On-Pump), were randomly allocated to 3 groups: A, B, C. Group A (CPAP) patients received CPAP at 10 cm H2O during CPB. Group B (IMV) patients received IMV with a tidal volume of 2 cc/kg and respiratory rate of 15/min and group C (control) patients did not receive any type of ventilation during CPB. Other procedures were similar between groups. Arterial blood samples were taken at 8 moments and arterial blood gas (ABG) analysis were compared between groups. Chest x-rays after CABG were also evaluated with respect to atelectasis. RESULTS: The demographic data were similar in between three groups. Graft number, pump time and preoperative ABGs were not significantly different. Postoperative PaO2 were significantly higher in the CPAP and IMV groups and (A-a) DO2 were significantly lower in these two groups, compared to the control group. CONCLUSIONS: In the present study, applying positive airway pressure methods (CPAP or IMV) during CPB was associated with better postoperative ABG measurements and (A-a) DO2.