Ventilation strategy for video-assisted thoracoscopic clipping of patent ductus arteriosus in children

Lung protective ventilation in patients undergoing major surgery: a systematic review incorporating a Bayesian approach

OBJECTIVE

Protective ventilation (PV) has been validated in patients with acute respiratory distress syndrome. However, the effect of PV in patients undergoing major surgery is controversial. The study aimed to explore the beneficial effect of PV on patients undergoing a major operation by systematic review and meta-analysis.

SETTING

Various levels of medical centres.

PARTICIPANTS

Patients undergoing general anaesthesia.

INTERVENTIONS

PV with low tidal volume.

PRIMARY AND SECONDARY OUTCOME MEASURES

Study end points included acute lung injury (ALI), pneumonia, atelectasis, mortality, length of stay (LOS) in intensive care unit (ICU) and hospital.

METHODS

Databases including PubMed, Scopus, EBSCO and EMBASE were searched from inception to May 2015. Search strategies consisted of terms related to PV and anaesthesia. We reported OR for binary outcomes including ALI, mortality, pneumonia, atelectasis and other adverse outcomes. Weighted mean difference was reported for continuous outcomes such as LOS in the ICU and hospital, pH value, partial pressure of carbon dioxide, oxygenation and duration of mechanical ventilation (MV).

MAIN RESULTS

A total of 22 citations were included in the systematic review and meta-analysis. PV had protective effect against the development of ALI as compared with the control group, with an OR of 0.41 (95% CI 0.19 to 0.87). PV tended to be beneficial with regard to the development of pneumonia (OR 0.46, 95% CI 0.16 to 1.28) and atelectasis (OR 0.68, 95% CI 0.46 to 1.01), but statistical significance was not reached. Other adverse outcomes such as new onset arrhythmia were significantly reduced with the use of PV (OR 0.47, 95% CI 0.48 to 0.93).

CONCLUSIONS

The study demonstrates that PV can reduce the risk of ALI in patients undergoing major surgery. However, there is insufficient evidence that such a beneficial effect can be translated to more clinically relevant outcomes such as mortality or duration of MV.

TRIAL REGISTRATION NUMBER

The study was registered in PROSPERO (http://www.crd.york.ac.uk/PROSPERO/) under registration number CRD42013006416.

Continuous positive airway pressure and lung separation during cardiopulmonary bypass to facilitate congenital heart surgery via the right thorax in children

We describe a fast track anesthesia technique that facilitates congenital heart surgery via right axillary thoracotomy in children. Continuous positive airway pressure on the dependent lung, before and during cardiopulmonary bypass, approximates the heart towards the chest wall incision, and significantly improves the surgeon's access to the heart.

High-frequency jet ventilation: Utility in posterior left atrial catheter ablation

BACKGROUND

Percutaneous catheter ablation in the posterior left atrium (LA) is a technically demanding procedure that in our experience is best accomplished using general anesthesia, including endotracheal intubation and mechanical ventilation. However, using conventional intermittent positive-pressure ventilation (IPPV) technique, we were dissatisfied with motion of the posterior LA. This occurred during changes in lung volume, which destabilized ablation electrode-endocardial contact. We hypothesized that use of high-frequency jet ventilation (HFJV), a low-volume, fast-rate technique, would reduce posterior LA motion and thus facilitate the ablation procedure.

OBJECTIVES

The purpose of this study was to demonstrate that, relative to IPPV, HFJV reduces posterior LA motion and facilitates catheter ablation in this region.

METHODS

Patients who underwent posterior LA ablation using HFJV (n = 36) were retrospectively compared with those in whom IPPV (n = 36) was used. Indices examined included number of radiofrequency energy applications, electrode temperature, and procedure time. A prospective direct comparison of the impact of HFJV and IPPV on LA volume and mechanical function was performed in an additional 10 patients.

RESULTS

Fewer ablation lesions were required in the HFJV group because of fewer incidences of ablation electrode dislodgment, resulting in significantly decreased procedure time. Although there was no significant difference in maximal electrode temperature achieved during radiofrequency application, temperature variation was diminished in the HFJV group. Direct comparison demonstrated that HFJV produced less variation in LA volume, pressure, pulmonary vein blood flow velocity, and posterior LA position than IPPV.

CONCLUSION

Relative to IPPV, HFJV yields a more stable posterior LA environment, thus facilitating catheter ablation. Use of HFJV may be applicable to other interventional cardiovascular procedures.

Tolerance of laparoscopy and thoracoscopy in neonates

OBJECTIVES

Video-surgery in neonates is recent. Data on the respiratory, hemodynamic, and thermic effects during the first month of life are still sparse. This study aimed to evaluate the tolerance of video-surgery in neonates and to determine the risk factors of per-operative complications.

METHODS

From 1994 to 2004, 49 neonates (mean age: 11 days; weight: 3285 g) underwent 50 video-surgical procedures. Indications for laparoscopy were duodenal atresias, volvulus with malrotation, pyloric stenosis, gastroesophageal reflux, cystic lymphangiomas, ovarian cysts, biliary atresia, and congenital diaphragmatic hernias; indications for thoracoscopy were esophageal atresias and tracheoesophageal fistula.

RESULTS

Median operative time was 79 minutes. Mean insufflation pressure was 6.7 mm Hg (range: 3-13). Oxygen saturation decreased, especially with thoracic insufflation or high-pressure pneumoperitoneum. Systolic arterial pressure, which decreased in 20% of the patients, was controlled easily with vascular expansion. Thermic loss (mean postoperative temperature: 35.6 degrees C) was proportional to the duration of insufflation. No surgical incident was noted. Ten anesthetic incidents occurred (20%), 3 of which required temporary or definitive interruption of insufflation (O2 saturation <70%). Risk factors for an incident were low preoperative temperature, high variation of end-tidal pressure of CO2, surgical time >100 minutes, thoracic insufflation, and a high oxygen or vascular expansion requirement at the beginning of insufflation.

CONCLUSION

The neonate's high sensitivity to insufflation is an important limiting factor of video-surgery. The described profile of the neonate at risk may help to reduce the frequency of adverse effects of this technique and improve its tolerance.