What is the value of topical cooling as an adjunct to myocardial protection?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'What is the value of topical cooling as an adjunct to myocardial protection?' Using the reported search, 9 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The studies included four randomized controlled trials (RCTs). Two RCTs demonstrated no cardioprotective effects of topical hypothermia as they found no statistically significant differences in myocardial markers between patients with or without topical cooling. In a randomized study of 249 patients undergoing elective cardiac surgery, phrenic nerve injury and failure of extubation occurred more frequently with the use of topical hypothermia with iced slush (P = 0.009 and P = 0.034, respectively). One retrospective analysis found that patients who received iced topical hypothermia had longer postoperative hospitalization, higher incidence of atelectasis and higher left diaphragms on chest X-ray. Another study showed increased morbidity and mortality associated with postoperative diaphragmatic dysfunction resulting from the use of iced slush topical cooling of the heart. We conclude that topical cooling is an unnecessary adjunct to myocardial protection in patients undergoing cardiac surgery. There is no evidence of any additional cardioprotective benefit. Several studies showed that the use of topical hypothermia is associated with phrenic nerve injury, leading to diaphragmatic paralysis and increased pulmonary complications. Moreover, long-term follow-up data showed often incomplete regression of the phrenic nerve paralysis. However, few randomized studies exist on the value of topical cooling as an adjunct to myocardial protection.

Which patients should be on renin-angiotensin system blockers after coronary surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'which patients should be on renin-angiotensin system blockers after coronary surgery?' Using the reported search, 12 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The 12 studies included 5 prospective randomized controlled trials (RCTs) and 1 meta-analysis. One RCT of 2553 stable patients post-coronary artery bypass surgery (CABG) with left ventricular (LV) ejection fraction ≤40% showed that angiotensin-converting enzyme inhibition (ACEI) therapy can and probably should be delayed beyond 7 days due to increased cardiovascular morbidity and mortality associated with immediate postoperative initiation of ACEI treatment. Another study showed that the cardioprotective benefits of ACEI following CABG are persistent with respect to an LV ejection fraction below or above 40% and whether percutaneous coronary intervention (PCI) or CABG was performed. A large multicentre international study of 4224 patients undergoing CABG looking at a composite outcome of rates of cardiac, cerebral and renal events and in-hospital mortality showed that continuous treatment with ACEI compared with no ACEI was associated with reductions of risks of non-fatal events (P = 0.009, odds ratio 0.69, 95% confidence interval 0.52-0.91). Addition of ACEI de novo following surgery was also associated with significant reduction in the risk of the composite outcome (P = 0.004) and of a cardiovascular event (P = 0.04). We conclude that angiotensin-converting enzyme inhibitor treatment plays an important role in minimizing ischaemic events after CABG even in low-risk patients. The cardioprotective benefits of these drugs are persistent at mid- and long-term follow-up, with respect to LV ejection fraction below or above 40% and whether PCI or CABG was performed. Not only continuation of angiotensin-converting enzyme inhibition early after surgery but also adding ACEI de novo postoperatively can be associated with better cardiovascular and renal outcomes.

Long-term outcomes following high intensity focused ultrasound ablation for atrial fibrillation.

BACKGROUND AND OBJECTIVE: The aim of this study is to assess the safety and efficacy of the Epicor high intensity focused ultrasound (St. Jude, Inc.®, Minneapolis, MN, USA) system using seven-day ambulatory electrocardiogram (ECG) monitoring over a two-year follow-up period. METHODS: One hundred and ten patients undergoing ablation were included from a single center between January 2006 and December 2009. Rhythm was assessed using seven-day ambulatory ECG or permanent pacemaker interrogation. Seventeen patients were lost to follow-up, seven through death. Results were reported according to atrial fibrillation (AF) class preoperatively: paroxysmal, persistent, and long-standing persistent (LSP). RESULTS: Forty-nine percent of patients remained in sinus rhythm at greater than two years. The percentage of patients in sinus rhythm according to preoperative AF class were 81% (paroxysmal AF), 56% (persistent AF), and 18% (long-standing AF). The class of AF prior to surgery, left atrium size, and body mass index determined the long-term outcome. There were no procedure-related complications. CONCLUSIONS: We conclude that high intensity focused ultrasound ablation for atrial fibrillation using the Epicor system is safe and effective for surgical patients with paroxysmal AF. The persistent and LSP AF results suggest that alternative ablation strategies should be considered for these patients.

Oxygen delivery during cardiopulmonary bypass (and renal outcome) using two systems of extracorporeal circulation: a retrospective review.

OBJECTIVES: To investigate the combined influence of blood flow and haemodilution with either a miniaturized (Mini-CPB) or a conventional cardiopulmonary bypass (C-CPB) circuit on average oxygen delivery during bypass. The influence of this on clinical outcome, particularly renal dysfunction after routine coronary artery bypass surgery (CABG), was measured. METHODS: Retrospective analysis in two groups of 160 patients based on the surgeon's preference for bypass circuit. We compared consecutive patients undergoing isolated CABG surgery by two surgeons using Mini-CPB with a matched cohort of patients, from the same period, undergoing isolated CABG surgery by four other surgeons using a C-CPB. No trial-related intervention occurred. Data on bypass circuit parameters and clinical outcomes were acquired from routinely collected data sources. RESULTS: Average cardiopulmonary bypass pump flow was significantly lower with Mini-CPB compared with C-CPB. Mini-CPB resulted in significantly less haemodilution. The resultant calculated average oxygen delivery provided by the two systems was the same. Percentage change in plasma creatinine was significantly and inversely related to the oxygen delivery during CPB. There was no difference in percentage change in plasma creatinine between groups. The risk of having Acute Kidney Injury Network (AKIN) score ≥ 1 increased 1% for every 1 ml min(-1) m(-2) decrease in oxygen delivery (P = 0.0001, OR 0.990, 95% CI 0.984-0.995). CONCLUSIONS: Despite aiming for the same target pump flow, periodic limitations of venous return to the pump resulted in a significant reduction in average flow delivered to the patient by Mini-CPB. Less haemodilution compensated for this reduction, so that the average oxygen delivery was the same. The association between oxygen delivery and postoperative change in plasma creatinine was evident in both groups. Further work to understand whether there is a particular cohort of patients who benefit (or are put at risk) by one method of CPB vs the other is warranted.

Ambulatory intercostal drainage for the management of malignant pleural effusion: a single center experience.

BACKGROUND: Malignant pleural effusions are common and can be difficult to manage. We have reviewed our use of ambulatory drains (Pleurex drains) in this regard with particular reference to hospital stay, duration of drainage, and incidence of complications. MATERIALS AND METHODS: Of 125 patients with malignant pleural effusion with trapped lung or failed previous pleurodesis who underwent insertion of ambulatory pleural drain, 41 patients were under local anesthesia and 84 patients were under general anesthesia. Mean age was 66.5 years with male:female = 80:45. Data were collected retrospectively from the clinical notes, and the family doctors' clinics were contacted to enquire about the patients' survival. RESULTS: When data collection concluded, 48 patients (38.4%) had died, giving mean survival following drain insertion of 84.1 days. There were no in-hospital deaths related to the procedure. One procedure was converted to a mini-thoracotomy to control bleeding from a lung tear. Mean duration of catheter placement was 87.01 days (5-434). Video-assisted thoracoscopic surgery was used in 77 patients (61.6%), and Seldinger's technique was used in 48 patients (38.4%). Mesothelioma was the most common malignant cause. Minor complications were encountered in 15 patients (12%), and they were managed as outpatients. CONCLUSION: The use of ambulatory pleural catheters for managing malignant pleural effusion is a safe and effective strategy. It has only minor complications that are related to prolonged drainage. We feel that this strategy should be considered the first choice option for these patients.

Stented esophageal transfixion injury.

Esophageal perforation is a rare, but life-threatening condition with a mortality rate ranging between 10% and 40%. It can happen at the level of the cervical, intrathoracic, or intra-abdominal segment. It usually occurs as a result of iatrogenic injury after endoscopic procedures or as a spontaneous rupture. It is seen less frequently in trauma after gunshot or stab wounds. Stenting of the esophagus after iatrogenic perforation is well documented in the literature, but yet it is to be published for management of penetrating injury. We report a case of esophageal perforation with a wooden fence post treated successfully with a covered esophageal stent.

Risk factors of spontaneous pneumothorax in Kuwait.

OBJECTIVES: To determine the risk factors of spontaneous pneumothorax (SP) in Kuwait. SUBJECTS AND METHODS: From January 2002 through December 2003, 254 consecutive cases with a diagnosis of SP were reviewed. Analyses of pneumothorax rates by age, sex, smoking, body mass index (BMI) and climatic conditions were evaluated. RESULTS: Of the 254 patients, 242 (95%) were male and 12 (5%) were female; a larger proportion of 180 (88%) were Kuwaitis and 74 (12%) were expatriates. Two hundred and eight (82%) episodes were regarded as primary SP and 46 (18%) as secondary SP. The mean age was 24.5 +/- 5.8 years for primary SP and 45.7 +/- 14.5 years for secondary SP. One hundred and ninety-six (77%) individuals were current smokers. BMI in primary and secondary SP was 19.3 and 22.4, respectively (p < 0.001). There was no relationship between SP and climatic conditions (a rise or fall in temperature, humidity or atmospheric pressure). However, a slight increase in SP occurred in July, probably the hottest month in Kuwait. CONCLUSIONS: The data indicate that the most important risk factors of SP in Kuwait are smoking, low BMI and the male gender.

Pulmonary complications following major lung resection for benign and malignant lung diseases.

OBJECTIVE: To assess the incidence and to identify the possible associated risk factors for postoperative pulmonary complications after major lung resection. SUBJECTS AND METHODS: One hundred and sixty-eight consecutive patients undergoing major lung resection for benign and malignant lung disease over a 3-year period were included in the study. Preoperative assessment clinical parameters, intraoperative and postoperative events were recorded. Pulmonary complications were noted according to a precise definition. The risk of complications associated with age, comorbidity, forced vital capacity (FVC), blood transfusion and extended operation was evaluated using logistic regression analysis. RESULTS: The mean age of the patients was 47.1 years (range 16-80 years), 137 (77%) patients underwent lobectomy, 23 (14%) pneumonectomy, and 15 (9%) bilobectomy. Forty-six (27%) patients developed postoperative pulmonary complications and 2 (1.1%) died within 30 days following the operation. Age > or =65 years (OR 3.7, 95% CI: 1.5-8.6, p = 0.002), the presence of comorbid cardiopulmonary disease (OR 0.2, 95% CI: 0.1-0.5, p = 0.001), FVC <50% (OR 0.2, 95% CI: 0.1-0.8, p = 0.02), blood transfusion (OR 0.2, 95% CI: 0.1-0.4, p = 0.0001), and extended operation (OR 0.2, 95% CI: 0.07-0.6, p = 0.005) were the identified factors associated with the development of postoperative pulmonary complications, which necessitated an increased length of hospital stay. CONCLUSION: Postoperative pulmonary complications are more likely to develop in patients with age > or =65 years with comorbid cardiopulmonary disease, FVC <50%, blood transfusion, and extended operation.

Pulmonary arteriovenous malformation presenting with severe hypoxemia.

OBJECTIVE: To report a case of right pulmonary arteriovenous malformation (PAVM) affecting the right upper lobe, following the incidence of empyema thoracis in the contralateral lung. CLINICAL PRESENTATION AND INTERVENTION: A 19-year-old, previously healthy male presented with acute respiratory distress, left pleuritic chest pain, fever and hypoxemia. Clinical findings, laboratory and radiological examinations including pulmonary angiogram were consistent with the diagnosis of left pneumonia complicated with parapneumonic pleural effusion and right upper lobe PAVM. The patient was intubated and ventilated because of persistent hypoxemia. He was successfully treated by percutaneous transcatheter embolization. CONCLUSION: This case shows that percutaneous transcatheter embolization is a safe and effective first option for the treatment of PAVM.