Pulmonary artery size as an indication for thoracoscopic repair of congenital diaphragmatic hernia in neonates

Pulmonary artery diameter ratio as a prognostic indicator of congenital diaphragmatic hernia

Background

Following on from an earlier study published in 2008 about left pulmonary artery (LPA) flow measured on serial echocardiography being strongly prognostic in left-sided congenital diaphragmatic hernia (CDH) and the ratio of LPA to right pulmonary artery (RPA) diameters being a simple and reliable indicator for commencing nitric oxide (NO) therapy, the ratio of LPA:RPA diameters (PA ratio or PAR) was hypothesized to possibly reflect cardiopulmonary stresses accompanying CDH better.

Methods

Subjects with isolated left-sided CDH treated between 2007 and 2020 at a single pediatric surgical center were recruited and classified according to survival. Data obtained retrospectively for subject demographics, clinical course, LPA/RPA diameters, and PAR were compared between survivors and non-survivors. The value of PAR for optimizing the prognostic value of PA diameter data in CDH were analyzed with receiver operating characteristic (ROC) curve analysis.

Results

Of 65 subjects, there were 54 survivors (82.3%) and 11 non-survivors (17.7%); 7 of 11 non-survivors died before surgical repair could be performed. Mean PAR for survivors (0.851±0.152) was significantly higher than for non-survivors (0.672±0.108) (p=0.0003). Mean PAR for non-survivors was not affected by surgical repair. Characteristics of survivors were: LPA ≥2 mm (n=52 of 54; mean PAR=0.866±0.146) and RPA ≥3 mm (n=46 of 54; mean PAR=0.857±0.152). Non-survivors with similar LPA and RPA diameters to survivors had significantly lower mean PAR. ROC curve cut-off for PAR was 0.762. Subjects with high PAR (≥0.762) required high-frequency oscillatory ventilation/NO less than subjects with low PAR (<0.762) (p=0.0244 and p=0.0485, respectively) and subjects with high PAR stabilized significantly earlier than subjects with low PAR (1.71±0.68 days vs 3.20±0.87 days) (p<0.0001).

Conclusions

PAR would appear to be strongly correlated with clinical outcome in CDH and be useful for planning management of cardiopulmonary instability in CDH.

Safety of surgery for neonatal congenital diaphragmatic hernia as reflected by arterial blood gas monitoring: thoracoscopic versus open repair

PURPOSE

We monitored arterial blood gases during thoracoscopic (TR) and open repair (OR) of congenital diaphragmatic hernia (CDH) to assess the safety of intraoperative hypercapnia and acidosis.

METHODS

We reviewed 30 neonatal CDH cases (OR = 10, TR = 20) diagnosed prenatally or within 6 h of birth at out institution from 2002 to 2014 not requiring inhaled nitric oxide (NO) intraoperatively. OR, routine until 2006 was replaced by TR in 2007. All subjects were managed identically.

RESULTS

Five TR cases requiring conversion to OR were excluded. Prenatal diagnosis, gestational age at birth, gender, birth weight, and side of CDH were similar. Preoperative PaCO2 and pH were not significantly different. However, while intraoperative increase in mean PaCO2 (38.8-62.8 mmHg; p < 0.01) and decrease in mean pH (7.44-7.25; p < 0.01) were significant in TR, intraoperative PaCO2 was <70 mmHg in 12/15 cases and intraoperative pH was >7.20 in 11/15 cases. Both PaCO2 and pH reverted to normal on completion of surgery; pre- and postoperative results were comparable. There were no postoperative complications.

CONCLUSIONS

It would appear that neonatal cases of CDH not requiring NO can tolerate TR, despite transient reversible deterioration in acid/base balance, indicating that TR is safe for the treatment of selected cases of CDH.

Advances in the surgical approach to congenital diaphragmatic hernia

Congenital diaphragmatic hernia is a birth defect that affects about one in 2500 live births. Although the overall survival has improved over the last several decades thanks to advancements in postnatal resuscitation and intensive care treatment, morbidity and mortality remain high. The surgical management of these infants is far from being standardized, and many aspects are still disputed among experts. The timing of surgical repair remains controversial and the indications for the ideal time for surgery have not been validated. The main novelty in the surgical treatment is related to the use of minimally invasive techniques, although these have been associated with intraoperative blood gas disturbances and higher recurrence rates. Herein, we report and comment on the main controversies of postnatal CDH repair in this rapidly evolving field.

[Indication: scientific and ethical basis of medical practice]

The medical indication provides a rational foundation for treatment decisions. An indication can be defined as the reasonable professional judgement that a medical procedure is suitable and useful to reach a specific therapeutic goal with a certain probability. An indication includes empirical, causal and purposive considerations and justifications, and a scrutiny of the individual case. This ensures that medical aspects of the patient, therapeutic goals and evidence-based knowledge are integrated and represented in the indication. An indication justifies a treatment proposal to the patient, which may only be carried out after a procedure of informed consent. Indications can be considered as the ethical basis of treatment decisions and as the heart of professionalism: indications should be used as a professional tool to protect against irrational therapeutic expectations, while ensuring the patient's right for reasonable treatment. In health care that is increasingly shaped by economic constraints, conscientious indications ensure the professional and ethical basis of medical treatment decisions.

Surgical intervention for congenital diaphragmatic hernia: open versus thoracoscopic surgery

PURPOSE

To compare open repair (OR) with thoracoscopic repair (TR) for congenital diaphragmatic hernia (CDH) in neonates.

METHODS

Twenty-four neonatal CDH cases diagnosed prenatally or within 6 h of birth at our institute from 2002 to 2012 with mild pulmonary hypertension managed without inhaled nitric oxide, were studied. OR was routine until 2006 (n = 14; L:R = 12:2) and TR became routine in 2007 (n = 10; L:R = 10:0). All subjects had identical management.

RESULTS

Gestational age at birth: OR 37.4 ± 1.6 vs. TR: 38.3 ± 1.1 weeks (p = 0.10); birth weight 2,636 ± 490 vs. 2,887 ± 429 grams (p = 0.20); preoperative A-aDO(2): 308 ± 200 vs. 331 ± 195 mmHg (p = 0.79); and operating time (min): 161 ± 42 vs. 194 ± 76 (p = 0.27). In TR, intraoperative cardiopulmonary status was stable, intraoperative hemorrhage was significantly less (4.8 ± 6.0 vs. 1.1 ± 0.1 grams; p = 0.038), wound cosmesis was excellent without surgical site infections, while, maximum postoperative CRP (2.0 ± 1.5 vs. 1.5 ± 1.1 mg/dL; p = 0.30), commencement of enteral feeding (6.9 ± 2.8 vs. 5.6 ± 2.8 days; p = 0.27), and length of postoperative hospitalization (36 ± 22 vs. 34 ± 12 days; p = 0.66) were improved, but not significantly. One OR case required surgery for intestinal obstruction.

CONCLUSIONS

Thoracoscopic repair appears to be as effective as OR for treating selected cases of CDH in neonates, with excellent wound cosmesis.