Post-cardiopulmonary bypass hypoxaemia in paediatric patients undergoing congenital heart disease surgery: risk factors, features, and postoperative pulmonary complications

Effect of one-lung ventilation in children undergoing lateral thoracotomy cardiac surgery with cardiopulmonary bypass on postoperative atelectasis and postoperative pulmonary complications

BACKGROUND

Right lateral thoracotomy is increasingly used because of its cosmetic benefits, shorter hospital stays, rapid return to full activity, and ease of reoperation in pediatric patients with uncomplicated congenital heart disease. Currently, one-lung ventilation (OLV) is used in these children to facilitate surgical exposure. We aimed to assess the effect of OLV on postoperative outcomes.

METHODS

Children aged 6 months to 6 years undergoing right lateral thoracotomy cardiac surgery with cardiopulmonary bypass (CPB) were randomized into an OLV group or a control group. For the OLV group, the tidal volume was 5 ml/kg with 6 cmH₂O positive end-expiratory pressure from the incision until the end of CPB, whereas patients in the control group received two-lung ventilation, except during vena cava occlusion. Lung ultrasonography was performed twice in the supine position for each patient: first, 3 min after intubation before surgery (T1), and second, 3 min after lung recruitment maneuvers at the end of surgery (T2). The primary outcome was the incidence of postoperative pulmonary complications within 72 h of surgery and significant atelectasis (defined by a consolidation score of ≥ 2 in any region) at T2.

RESULTS

Overall, 54/96 (56.3%) children developed postoperative pulmonary complications after lateral thoracotomy cardiac surgery with CPB. The incidence of postoperative pulmonary complications was 52.1% (25/48) and 60.4% (29/48) in the OLV and control groups, respectively (odds ratio: 0.712; 95% confidence interval: 0.317-1.600; p = .411). At the end of surgery, the incidence of significant atelectasis was 37.5% in the OLV group compared to 64.6% in the control group (odds ratio: 0.329; 95% confidence interval: 0.143-0.756; p = .008). The consolidation score of the left lung (dependent lung) in the OLV group was significantly lower than that in the control group (p = .007); there was no significant difference in the right lung's postoperative consolidation score between the two groups (p = .051).

CONCLUSIONS

There was no significant difference in the incidence of postoperative pulmonary complications within 72 h of surgery between the two groups. However, children who underwent right lateral thoracotomy cardiac surgery with CPB in the OLV group showed a low incidence of atelectasis at the end of surgery.

TRIAL REGISTRATION

ChiCTR, ChiCTR2100048720. Registered on July 13, 2021, www.chictr.org.cn .

Effect of nitric oxide delivery via cardiopulmonary bypass circuit on postoperative oxygenation in adults undergoing cardiac surgery (NOCARD trial): a randomised controlled trial

BACKGROUND

Cardiac surgery involving cardiopulmonary bypass induces a significant systemic inflammatory response, contributing to various postoperative complications, including pulmonary dysfunction, myocardial and kidney injuries.

OBJECTIVE

To investigate the effect of Nitric Oxide delivery via the cardiopulmonary bypass circuit on various postoperative outcomes.

DESIGN

A prospective, single-centre, double-blinded, randomised controlled trial.

SETTING

Rabin Medical Centre, Beilinson Hospital, Israel.

PATIENTS

Adult patients scheduled for elective cardiac surgery were randomly allocated to one of the study groups.

INTERVENTIONS

For the treatment group, 40 ppm of nitric oxide was delivered via the cardiopulmonary bypass circuit. For the control group, nitric oxide was not delivered.

OUTCOME MEASURES

The primary outcome was the incidence of hypoxaemia, defined as a p a O2 /FiO 2 ratio less than 300 within 24 h postoperatively. The secondary outcomes were the incidences of low cardiac output syndrome and acute kidney injury within 72 h postoperatively.

RESULTS

Ninety-eight patients were included in the final analysis, with 47 patients allocated to the control group and 51 to the Nitric Oxide group. The Nitric Oxide group exhibited significantly lower hypoxaemia rates at admission to the cardiothoracic intensive care unit (47.1 vs. 68.1%), P  = 0.043. This effect, however, varied in patients with or without baseline hypoxaemia. Patients with baseline hypoxaemia who received nitric oxide exhibited significantly lower hypoxaemia rates (61.1 vs. 93.8%), P  = 0.042, and higher p a O2 /FiO 2 ratios at all time points, F (1,30) = 6.08, P  = 0.019. Conversely, this benefit was not observed in patients without baseline hypoxaemia. No significant differences were observed in the incidence of low cardiac output syndrome or acute kidney injury. No substantial safety concerns were noted, and toxic methaemoglobin levels were not observed.

CONCLUSIONS

Patients with baseline hypoxaemia undergoing cardiac surgery and receiving nitric oxide exhibited lower hypoxaemia rates and higher p a O2 /FiO 2 ratios. No significant differences were found regarding postoperative pulmonary complications and overall outcomes.

TRIAL REGISTRATION

NCT04807413.

Comparison of high-flow nasal cannula oxygenation and non-invasive ventilation for postoperative pediatric cardiac surgery: a meta-analysis

OBJECTIVE

To evaluate the efficacy of high-flow nasal cannula oxygenation (HFNC) versus non-invasive ventilation (NIV) in pediatric patients post-congenital heart surgery (CHS) through a meta-analysis.

METHODS

A comprehensive literature search was conducted across the Chinese biomedical literature database, Vip database, CNKI, Wanfang, PubMed, Embase, Cochrane Library, and Web of Science until December 20, 2022. We selected RCTs or cohort studies that met inclusion criteria for a meta-analysis using RevMan 5.4 software.

RESULTS

Our search yielded five publications, comprised of one randomized controlled trial and four cohort studies. Meta-analysis revealed a significant reduction in reintubation rates in children post-CHS treated with HFNC as compared to NIV [RR = 0.36, 95%CI(0.25 ~ 0.53), P < 0.00001]. There was also a notable reduction in the duration of ICU stay [MD = -4.75, 95%CI (-9.38 ~ -0.12), P = 0.04]. No statistically significant differences were observed between HFNC and NIV in terms of duration of mechanical ventilation, 24 h PaO2, and PaCO2 post-treatment (P > 0.05). Furthermore, both groups showed no significant difference in the duration of extracorporeal circulation [MD = -8.27, 95%CI(-17.16 ~ 0.62), P = 0.07].

CONCLUSIONS

For pediatric patients post-CHS, HFNC appears to be more effective than NIV in reducing reintubation rates and shortening the CICU stay.