Diaphragmatic paralysis after cardiac surgery in children: incidence, prognosis and surgical management

In a porcine model of implantable pacemakers for pediatric unilateral diaphragm paralysis, the phrenic nerve is the best target

BACKGROUND

A frequent complication of Fontan operations is unilateral diaphragmatic paresis, which leads to hemodynamic deterioration of the Fontan circulation. A potential new therapeutic option is the unilateral diaphragmatic pacemaker. In this study, we investigated the most effective stimulation location for a potential fully implantable system in a porcine model.

METHODS

Five pigs (20.8 ± 0.95 kg) underwent implantation of a customized cuff electrode placed around the right phrenic nerve. A bipolar myocardial pacing electrode was sutured adjacent to the motor point and peripherally at the costophrenic angle (peripheral diaphragmatic muscle). The electrodes were stimulated 30 times per minute with a pulse duration of 200 µs and a stimulation time of 300 ms. Current intensity was the only variable changed during the experiment.

RESULTS

Effective stimulation occurred at 0.26 ± 0.024 mA at the phrenic nerve and 7 ± 1.22 mA at the motor point, a significant difference in amperage (p = 0.005). Even with a maximum stimulation of 10 mA at the peripheral diaphragm muscle, however, no effective stimulation was observed.

CONCLUSION

The phrenic nerve seems to be the best location for direct stimulation by a unilateral thoracic diaphragm pacemaker in terms of the required amperage level in a porcine model.

Pulmonary blood flow in children with univentricular heart and unilateral diaphragmatic paralysis

OBJECTIVES

Spontaneous breathing has an important effect on pulmonary arterial blood flow in patients with Glenn/Fontan circulation. Unilateral diaphragmatic paralysis (DP) is a frequent complication after heart surgery in congenital heart disease. The aim of this study was to investigate the influence of unilateral DP on blood flow distribution in the pulmonary arteries with Glenn/Fontan circulation.

METHODS

Magnetic resonance phase-contrast imaging was used to evaluate stroke volume index (SVI) in the left and right pulmonary arteries in patients with Glenn/Fontan circulation with unilateral DP. Data for 18 patients with univentricular heart and unilateral DP were analysed, 8 in the Glenn stage and 10 in the Fontan stage. Ten patients had right-sided DP, and 8 had left-sided DP. A diaphragmatic plication was performed in 7 patients. The control group consisted of 36 patients with Glenn (n = 16)/Fontan (n = 20) circulation without DP.

RESULTS

In both left- and right-sided DP, the SVI to the ipsilateral side was significantly lower than in controls [2.81 (1.45-4.50) ml/m2 left vs 11.97 (7.36-16.37) ml/m2 in controls, P < 0.0002; 8.2 (4.49-12.64) ml/m2 with right vs 12.64 (9.66-16.61) ml/m2 in controls; P = 0.0284]. The SVI to the contralateral side showed a slight but non-significant increase in the presence of unilateral DP.

CONCLUSIONS

Unilateral DP in patients with Glenn/Fontan circulation has a negative impact on pulmonary arterial SVI on the side of the paralysis.

Towards Zero Phrenic Nerve Injury in Reoperative Pediatric Cardiac Surgery: The Value of Intraoperative Phrenic Nerve Stimulation

BACKGROUND

Phrenic nerve injury is a devastating complication that results in significant morbidity and mortality. We developed a novel technique to localize the phrenic nerve and evaluate its success.

METHODS

Two groups of children underwent repeat sternotomy for a variety of indications. Group I (69 patients, nerve stimulator) and Group II (78 patients, no nerve stimulator).

RESULTS

There was no significant difference in the mean age and weight between the two groups: (6.4 ± 6.5 years vs. 5.6 ± 6.4 years; p = 0.65) and (25.2 ± 24.1 vs. 22.6 ± 22.1; p = 0.69), respectively. The two groups were comparable in the following procedures: pulmonary conduit replacement, bidirectional cavopulmonary anastomosis, aortic arch repair, and Fontan, while Group I had more pulmonary arterial branch reconstruction (p = 0.009) and Group II had more heart transplant patients (p = 0.001). There was no phrenic nerve injury in Group I, while there were 13 patients who suffered phrenic nerve injury in Group II (p < 0.001). No early mortality in Group I, while five patients died prior to discharge in Group II. Eleven patients underwent diaphragm plication in Group II (p = 0.001). The mean number of hours on the ventilator was significantly higher in Group II (137.3 ± 324.9) compared to Group I (17 ± 66.9), p < 0.001. Group II had a significantly longer length of ICU and hospital stays compared to Group I (p = 0.007 and p = 0.006 respectively).

CONCLUSION

Phrenic nerve injury in children continues to be associated with significant morbidities and increased length of stay. The use of intraoperative phrenic nerve stimulator can be an effective way to localize the phrenic nerve and avoid its injury.

Predicting Factors for Mortality in Patients After the Modified Blalock-Taussig Shunt Procedure in Developing Countries: A Retrospective Study

Background

Blalock-Taussig (BT) is a palliative procedure that preserves blood circulation to the lungs and alleviates cyanosis in patients with congenital heart diseases and reduced pulmonary blood flow. BT shunt remains a routinely performed procedure in developing countries before definitive surgery. However, evidence on predictor factors of mortality after this procedure is still scarce in Indonesia. This study evaluated the predictive factors of mortality after the BT shunt procedure.

Methods

This retrospective study evaluated the medical record data of all postoperative BT shunt patients at Dr. Cipto Mangunkusumo Hospital, Jakarta, Indonesia, from 2016 to 2020. We performed univariate and multivariate analyses to identify the predictors of in-hospital mortality.

Results

The total subjects in this study were 197 children, 107 (54.3%) boys and 90 (45.7%) girls. The median values for age and body weight at the time of surgery were 20 months (11 days - 32 years) and 7.9 (2.7-42) kg. The most prevalent diagnosis was the Tetralogy of Fallot, found in 80 (40.6%) patients. In-hospital postoperative mortality was 20.8% (41 patients). Based on multivariate analysis, predictors associated with mortality were weight <4.25 kg (OR 20.9; 95% CI 7.4-59.0; p < 0.0001) and emergency procedures (OR 3.5; 95% CI 1.3-9.5; p = 0.016).

Conclusion

The mortality rate after BT shunt at PJT Rumah Sakit Cipto Mangunkusumo was 20.8%. Based on multivariate analysis, weight <4.25 kg and emergency procedures are two predictors of mortality in BT shunt.

Hemi-Diaphragm Plication and/or Tracheostomy Are Valuable Adjunctive Procedures After Repair of Congenital Heart Defects in Children: A Systematic Review

Diaphragmatic paralysis (DP), whether unilateral or bilateral, often leads to extended recovery and more severe complications, particularly in neonates and infants undergoing congenital heart surgery. This condition's impact is most pronounced after single-ventricle palliative procedures. Tracheostomy prevalence is rising in pediatric patients with congenital heart disease (CHD) despite its association with high resource utilization and in-hospital mortality. This study examines the reported incidence of diaphragmatic paralysis and timing of tracheostomy in pediatric patients undergoing surgery for congenital heart disease in the literature and a retrospective analysis of cases in our institution between 2018 and 2023, offering insights for prospective management. An electronic search of PubMed databases retrieved 10 studies on pediatric tracheostomy and 11 studies on DP. Our retrospective analysis included 15 patients, of whom 10 underwent tracheostomy, four underwent diaphragmatic plication, and one underwent both. Postoperative tracheostomy had an 11.8% mortality rate in our systematic review, rising to 40% in our observational study. Diaphragm repair and early diagnosis can reduce morbidity, prevent complications, and improve patients' quality of life.

Osteopathic Manipulative Treatment Decreases Hospital Stay and Healthcare Cost in the Neonatal Intensive Care Unit

Osteopathic manipulative treatment (OMT) is used in both inpatient and outpatient settings. Evidence suggests that OMT can reduce both patients' recovery time and the financial cost of their acute medical treatment and rehabilitation. Multiple studies from neonatal intensive care units (NICUs) are presented in this article that demonstrate infants treated with OMT recover faster, are discharged earlier, and have lower healthcare costs than their non-OMT-treated counterparts. Data clearly show that adjunctive OMT facilitates feeding coordination in newborns, such as latching, suckling, swallowing, and breathing, and increases long-term weight gain and maintenance, which reduces hospital length of stay (LOS). Osteopathic techniques, such as soft tissue manipulation, balanced ligamentous tension, myofascial release, and osteopathic cranial manipulation (OCM), can reduce regurgitation, vomiting, milky bilious, or bloody discharge and decrease the need for constipation treatment. OMT can also be effective in reducing the complications of pneumonia in premature babies. Studies show the use of OCM and lymphatic pump technique (LPT) reduces the occurrence of both aspiration and environmentally acquired pneumonia, resulting in significantly lower morbidity and mortality in infants. Based on published findings, it is determined that OMT is clinically effective, cost efficient, a less invasive alternative to surgery, and a less toxic choice to pharmacologic drugs. Therefore, routine incorporation of OMT in the NICU can be of great benefit in infants with multiple disorders. Future OMT research should aim to initiate clinical trial designs that include randomized controlled trials with larger cohorts of infants admitted to the NICU. Furthermore, a streamlined and concerted effort to elucidate the underlying molecular mechanisms associated with the beneficial effects of OMT will aid in understanding the significant value of incorporating OMT into optimal patient care.

Diagnostic Utility of Point-of-Care Ultrasound in the Pediatric Cardiac Intensive Care Unit

Purpose of Review

Recent Findings

Summary

Supplementary Information

Management of phrenic nerve injury post-cardiac surgery in the paediatric patient

BACKGROUND

Phrenic nerve injury is a common complication of cardiac and thoracic surgical procedures, with potentially severe effects on the health of a child. This review aims to summarise the available literature on the diagnosis and management of PNI post-cardiac surgery in paediatric patients with CHD.

MAIN BODY

The presence of injury post-surgery can be difficult to detect and may present with non-specific symptoms, emphasising the importance of an effective diagnostic strategy. Chest X-ray is usually the first investigation for a suspected diagnosis of PNI, which is usually confirmed using fluoroscopy, ultrasound scan, or phrenic nerve stimulation (gold standard). Management options include supportive ventilation and/or invasive diaphragmatic plication surgery. While the optimal timing of plication surgery remains controversial, it is now the most widely accepted treatment for PNI in children post-CHD surgery, especially for very young patients who cannot be weaned off supportive ventilation. Further research is needed to determine the optimal timing of surgical intervention for positive outcomes and to explore the benefits of using minimally invasive surgical techniques in children.

CONCLUSION

PNI is a common and serious complication of CHD surgery, therefore, its diagnosis and management in the paediatric population are of major importance. Further research is needed to determine the optimal timing of surgical intervention for positive outcomes and to explore the benefits of using minimally invasive surgical techniques in children.

Fluorographic findings of diaphragmatic paralysis with spontaneous recovery

BACKGROUND

Postoperative diaphragmatic paralysis is an unavoidable complication of cardiovascular surgery. Although diaphragmatic plication, as a surgical treatment, can be performed, spontaneous recovery is possible. We aimed to identify differences in fluorographic findings of diaphragmatic paralysis between pediatric patients with and without spontaneous recovery within 1 year of intrathoracic surgery.

METHODS

Ten children, who had been followed-up for at least 1 year post-surgery and who had not received diaphragmatic plication were included and classified into those with or without spontaneous recovery. The presence or absence of the paradoxical movement of the diaphragm and mediastinum was evaluated based on fluorographic findings. Fisher's exact test was used to compare the presence or absence of paradoxical movement between the groups.

RESULTS

Eight patients experienced spontaneous recovery. The mean ± standard deviation time to spontaneous recovery was 150 ± 114 days (range, 18-338 days). In the spontaneous recovery group, no patient had paradoxical movement of the mediastinum, and a significant between-group difference was observed in the presence of the paradoxical movement of the mediastinum (present/absent in patients with vs. without spontaneous recovery: 0/8 vs. 2/0, P = 0.02). There was no significant between-group difference in paradoxical movement of the diaphragm (present/absent in patients with vs. without spontaneous recovery: 1/7 vs. 2/0, P = 0.07). Pediatric patients without paradoxical movement of the mediastinum spontaneously recovered within 1 year of intrathoracic surgery.

CONCLUSIONS

Pediatric patients without paradoxical movement of the mediastinum, based on fluorography findings, spontaneously recovered within 1 year of surgery. The timing of spontaneous recovery varied between cases.

Outcome analysis of a conservative approach to diaphragmatic paralysis following congenital cardiac surgery in neonates and infants: a bicentric retrospective study

 

OBJECTIVES

Diaphragmatic paralysis following congenital cardiac surgery is associated with significant morbidity and mortality. Spontaneous recovery of diaphragmatic function has been described, contrasting with centres providing early diaphragmatic plication. We aimed to describe the outcomes of a conservative approach, as well as to identify factors associated with a failure of the strategy.

METHODS

This is a retrospective study of patients admitted after cardiac surgery and suffering unilateral diaphragmatic paralysis within 2 French Paediatric Cardiac Surgery Centers. The conservative approach, defined by the prolonged use of ventilation until successful weaning from respiratory support, was the primary strategy adopted in both centres. In case of unsuccessful evolution, a diaphragmatic plication was scheduled. Total ventilation time included invasive and non-invasive ventilation. Diaphragm asymmetry was defined by the number of posterior rib segments counted between the 2 hemi-diaphragms on the chest X-ray after cardiac surgery.

RESULTS

Fifty-one neonates and infants were included in the analysis. Patients' median age was 12.0 days at cardiac surgery (5.0-82.0), and median weight was 3.5 kg (2.8-4.9). The conservative approach was successful for 32/51 patients (63%), whereas 19/51 patients (37%) needed diaphragm plication. There was no difference in patients' characteristics between groups. Respiratory support prolonged for 21 days or more and diaphragm asymmetry more than 2 rib segments were independently associated with the failure of the conservative strategy [odds ratio (OR) 6.9 (1.29-37.3); P = 0.024 and OR 6.0 (1.4-24.7); P = 0.013, respectively].

CONCLUSIONS

The conservative approach was successful for 63% of the patients. We identified risk factors associated with the strategy's failure.

A novel sonographic sign of paradoxical movement of diaphragmatic paralysis in pediatric patients after cardiovascular surgery

We demonstrate a quick sliding of the descending aorta toward the unaffected side of the diaphragm as a new sonographic finding during breathing in pediatric patients with diaphragmatic paralysis. We present three pediatric patients with diaphragmatic paralysis after cardiovascular surgery with this new sonographic finding. This finding consisted of paradoxical movement of the diaphragm as shown by fluorography. This sonographic sign was only obtained by a B-mode scan in the subxiphoid plane, was easily demonstrated at the patient's bedside, and may be useful for diagnosing severe diaphragmatic paralysis.

Early diagnosis of diaphragm palsy after pediatric cardiac surgery and outcome after diaphragm plication - A single-center experience

Objective :

The aims of our prospective observational study were to evaluate the (1) reliability of clinical signs in the early detection of diaphragm palsy (DP); (2) reliability of ultrasonography using echo machine as a bedside tool for the diagnosis of DP; and (3) does early diaphragm plication result in the improved outcome? We also sought to determine the incidence and predominant risk factors for DP and diaphragm plication at our center.

Materials and Methods :

This prospective observational study included patients with suspected DP from January 2015 to December 2018. Patients with suspected DP were initially evaluated by bedside ultrasonography using echo machine and confirmed by fluoroscopy. Diaphragm plication was considered for patients having respiratory distress, difficult weaning, or failed extubation attempt without any obvious cardiac or pulmonary etiology. Patients were followed for 3 months after discharge to assess diaphragm function.

Results:

A total of 87 patients were suspected of DP based on clinical signs. DP was diagnosed in 61 patients on fluoroscopy. The median time from index operation to diagnosis was 10 (1–59) days. Diaphragm plication was done among 52 patients and not done in nine patients. Bedside ultrasonography using echo machine was 96.7% sensitive and 96.15% specific in diagnosing DP. Early plication (<14 days) significantly reduced the need for nasal continuous positive airway pressure (65% vs. 96%, P = 0.02), duration of mechanical ventilation (12 vs. 25 days, P = 0.018), intensive care unit (ICU) stay (25 days vs. 39 days, P = 0.019), and hospital stay (30 days vs. 46 days, P = 0.036).

Conclusion :

Hoover's sign and raised hemidiaphragm on chest X-ray are the most specific clinical signs to suspect unilateral DP. Bedside ultrasonography using an echo machine is a good diagnostic investigation comparable to fluoroscopy. Early plication facilitates weaning from the ventilator and thereby decreases the ICU stay and hospital stay.

Extracardiac Complications in Intensive Care Units after Surgical Repair for Congenital Heart Disease: Imaging Review with a Focus on Ultrasound and Radiography

Pediatric patients show various extracardiac complications after cardiovascular surgery, and radiography and ultrasound are routinely performed in the intensive care unit to detect and evaluate these complications. This review presents images of these complications, sonographic approach, and timing of occurrence that are categorized based on their extracardiac locations and include complications pertaining to the central nervous system, mediastinum, thorax and lung parenchyma, diaphragm, liver and biliary system, and kidney along with pleural effusion and iatrogenic complications. This pictorial review will make it easier for medical doctors in intensive care units to identify and manage various extracardiac complications in pediatric patients after cardiovascular surgery.

Diaphragm Paralysis After Pediatric Cardiac Surgery: An STS Congenital Heart Surgery Database Study

BACKGROUND

Previous single-center studies of diaphragm paralysis (DP) after pediatric cardiac surgery report incidence of 0.3% to 12.8% and associate DP with respiratory complications, prolonged ventilation and length of stay, and mortality. To better define incidence and associations between DP and various procedures and outcomes, we performed a multicenter study.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried to identify children who experienced DP after cardiac surgery (2010-2018; 126 centers). Baseline characteristics and postoperative outcomes were compared between patients with and without DP as well as between patients who underwent plication and those who did not. Associations between center volume and center rates of DP and use of plication were also explored.

RESULTS

A total of 2214 of 191,463 (1.2%) patients experienced DP. Postoperative DP portended worse outcomes, including mortality (5.6% vs 3.5%; P < .001), major morbidity (37.2% vs 10.7%; P < .001), tracheostomy (7.1% vs 0.9%; P < .001), prolonged mechanical ventilation (38.0% vs 7.8%; P < .001), and 30-day readmission (22.0% vs 10.6%; P < .001). A total of 1105 of 2214 (49.9%) patients with DP underwent plication. Patients who underwent plication were younger, were smaller, had more risk factors, and underwent more complex surgeries. Plication rates varied widely across centers. There was no correlation between center volume and center risk-adjusted rates of DP (r = .05, P = .5), nor frequency of plication (r = .08, P = .4).

CONCLUSIONS

DP complicating pediatric heart surgery is rare but portends significantly worse outcomes. One-half of patients underwent plication. Center-level risk-adjusted rates of DP and plication are not associated with case volume. Significant variability in plication practices suggests a target for quality improvement.

Ultrasonographic postoperative evaluation of diaphragm function of patients with congenital heart defects

Background

This study aims to investigate the role of ultrasonography in the postoperative evaluation of diaphragm function in patients with congenital heart defect.

Methods

This prospective study included a total of 360 patients (176 males, 184 females; mean age 2 years; range, 1 month to 8 years) who underwent congenital heart surgery and 44 patients (22 males, 22 females; mean age 1 years; range, 1 month to 4 years) who underwent diaphragm ultrasonography between September 2018 and March 2019. Ultrasonography was performed for the patients who had difficulty in weaning from mechanical ventilation or who were thought to have diaphragm dysfunction due to pathological findings on postoperative chest X-rays. The findings were interpreted as normal, paresis, or paralysis.

Results

Diaphragm dysfunction was demonstrated in 23 patients (6.3%), paralysis in 11 patients (3%), and paresis in 12 patients (3.3%). A median sternotomy was performed in 21 patients (91%), and seven of them (30%) were redo cases. Five patients (21%) had single ventricle physiology. Six patients (1.6%) needed an intervention due to diaphragm dysfunction. The interventional procedures were diaphragm plication in three patients (0.8%) and tracheotomy in three patients (0.8%). Three of these patients had a single ventricle and three had biventricular physiology. The median time after surgery for these procedures was 36 days. One patient (0.2%) died in the intensive care unit. The mean length of stay in the intensive care unit and hospital was 36±12 and 48±21 days, respectively.

Conclusion

Diaphragm dysfunction should be kept in mind in patients undergoing congenital heart surgery and in those who need prolonged intubation during the postoperative period. Ultrasonography is a non-invasive diagnostic tool which can be used to identify diaphragm dysfunction and the best course of management of this clinical condition.

Characteristics and outcomes of children with congenital heart disease needing diaphragm plication

BACKGROUND

Diaphragm dysfunction following surgery for congenital heart disease is a known complication leading to delays in recovery and increased post-operative morbidity and mortality. We aimed to determine the incidence of and risk factors associated with diaphragm plication in children undergoing cardiac surgery and evaluate timing to repair and effects on hospital cost and length of stay.

METHODS

We conducted a multi-institutional retrospective observational cohort study. Forty-three hospitals from the Pediatric Health Information System database were included, and a total of 112,110 patients admitted between January 2004 and December 2014 were analysed.

RESULTS

Patients less than 18 years of age who underwent cardiac surgery were included. Risk Adjustment for Congenital Heart Surgery was utilized to determine procedure complexity. The overall incidence of diaphragm dysfunction was 2.2% (n = 2513 out of 112,110). Of these, 24.0% (603 patients) underwent diaphragm plication. Higher complexity cardiac surgery (Risk Adjustment for Congenital Heart Surgery 5-6) and age less than 4 weeks were associated with a higher likelihood of diaphragm plication (p-value < 0.01). Diaphragmatic plication was associated with increased hospital length of stay (p-value < 0.01) and increased medical cost.

CONCLUSIONS

Diaphragm plication after surgery for congenital heart disease is associated with longer hospital length of stay and increased cost. There is a strong correlation of prolonged time to plication with increased length of stay and medical cost. The likelihood of plication increases with younger age and higher procedure complexity. Methods to improve early recognition and treatment of diaphragm dysfunction should be developed.

Diaphragmatic paralysis in young children: A literature review

Diaphragmatic paralysis (DP) is a rare cause of respiratory distress in young children. In the first years of life, the main cause is phrenic nerve injury after cardiothoracic surgery or obstetrical trauma. DP usually presents as respiratory distress. Asymmetrical thorax elevation, difficulty weaning from mechanical ventilation, pulmonary atelectasis, and repeated pulmonary infections are other suggestive signs or complications. DP is usually suspected on chest X-ray showing abnormal hemidiaphragm elevation. Although fluoroscopy was considered the gold standard for DP confirmation, it has gradually been replaced by ultrasound, which can be done at the bedside. Some electrophysiological tools may be useful for a better characterization of phrenic nerve injury and chance of recovery. The management of DP is mainly based on clinical severity. In mild asymptomatic cases, DP may only require close monitoring. In more severe cases, adequate ventilatory support and/or surgical diaphragmatic plication may be needed. Electrophysiological tools may help clinicians assess the ideal timing for diaphragmatic plication.

Pressure support ventilation, sigh adjunct to pressure support ventilation, and neurally adjusted ventilatory assist in infants after cardiac surgery: A physiologic crossover randomized study

OBJECTIVES

We sought to compare gas exchange, respiratory mechanics, and asynchronies during pressure support ventilation (PSV), sigh adjunct to PSV (PSV SIGH), and neurally adjusted ventilatory assist (NAVA) in hypoxemic infants after cardiac surgery.

DESIGN

Prospective, single-center, crossover, randomized physiologic study.

SETTING

Tertiary-care pediatric intensive care unit.

PATIENTS

Fourteen hypoxemic infants (median age 11.5 days [8.7-74]).

INTERVENTIONS

The protocol begins with a 1 hour step of PSV, followed by two consecutive steps in PSV SIGH and NAVA in random order, with a washout period of 30 minutes (PSV) between them.

MAIN RESULTS

Three infants presented an irregular Eadi signal because of diaphragmatic paralysis and were excluded from analysis. For the remaining 11 infants, PaO₂ /FiO ₂ and oxygenation index improved in PSV SIGH compared with PSV (P < 0.05) but not in NAVA compared with PSV. PSV SIGH showed increased tidal volumes and lower respiratory rate than PSV (P < 0.05), as well as a significant improvement in compliance with respiratory system indexed to body weight when compared with both PSV and NAVA (P < 0.01). No changes in mean airway pressure was registered among steps. Inspiratory time resulted prolonged for both PSV SIGH and NAVA than PSV (P < 0.05). NAVA showed the higher coefficient of variability in respiratory parameters and a significative decrease in asynchrony index when compared with both PSV and PSV SIGH (P < 0.01).

CONCLUSIONS

The adjunct of one SIGH per minute to PSV improved oxygenation and lung mechanics while NAVA provided the best patient-ventilator synchrony in infants after cardiac surgery.

Impact of Phrenic Nerve Palsy and Need for Diaphragm Plication Following Surgery for Pulmonary Atresia With Ventricular Septal Defect and Major Aortopulmonary Collaterals

Injury to the phrenic nerves may occur during surgery for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA-VSD and MAPCAs). These patients may develop respiratory failure and require diaphragm plication. The purpose of this study was to evaluate the impact of phrenic nerve palsy on recovery following surgery for PA-VSD and MAPCAs. Between 2007 and 2016, approximately 500 patients underwent surgery for PA-VSD and MAPCAs at our institution. Twenty-four patients (4.8%) subsequently had evidence of new phrenic nerve palsy. Sixteen patients were undergoing their first surgical procedure, whereas 8 were undergoing reoperations. All 24 patients underwent diaphragm plication. A cohort of matched controls was identified based on identical diagnosis and procedures but did not sustain a phrenic nerve palsy. Eighteen of the 24 patients (75%) had clinical improvement following diaphragm plication as evidenced by the ability to undergo successful extubation (5 ± 2 days), transition out of the intensive care unit (32 ± 16 days), and discharge from the hospital (42 ± 19 days). In contrast, there were 6 patients (25%) who did not demonstrate a temporal improvement following diaphragm plication, as evidenced by intervals of 61 ± 38, 106 ± 45, and 108 ± 46 days, respectively (P < 0.05 for all 3 comparisons). The 6 patients who failed to improve following diaphragm plication had a significantly greater number of comorbidities compared to the 18 patients who demonstrated improvement (2.2 vs 0.6 per patient, P < 0.05). When compared with the control group, patients who improved following diaphragm plication spent an additional 22 days and patients who failed to improve an additional 90 days in the hospital. The data demonstrate a bifurcation of clinical outcome in patients undergoing diaphragm plication following surgery for PA-VSD and MAPCAs. This bifurcation appears to be linked to the presence or absence of other comorbidities.

Bilateral Diaphragmatic Paralysis Following Paediatric Cardiac Surgery: Experience of four cases at the Royal Hospital, Muscat, Oman

Bilateral diaphragmatic paralysis (BDP) is a rare complication of paediatric cardiac surgery. We report four children who developed BDP following cardiac surgery who were managed at the Royal Hospital, Muscat, Oman, between 2009 and 2014. All four children suffered severe respiratory distress soon after extubation and required re-intubation within two hours. In addition, all of the children underwent a tracheostomy as an interim method for ventilation. The four children were successfully weaned from positive pressure ventilation following the functional recovery of at least one side of the diaphragm.

The advantage of early plication in children diagnosed with diaphragm paresis

BACKGROUND

In this single-center study, we sought to determine the frequency of phrenic nerve injury leading to diaphragm paresis (DP) in children following open cardiac surgery over the last 10 years, and to identify possible variables that predict the need for plication and associated clinical outcomes.

METHODS

Patients diagnosed with DP were identified from departmental databases and a review of clinical diaphragm ultrasound images. A cohort was analyzed for predictors of diaphragm plication and associations with clinical outcomes. Cumulative proportion graphs modeled the association between plication and length of stay.

RESULTS

DP was diagnosed in 161 of 6448 patients (2.5%) seen between January 2002 and December 2012. All diagnoses but 1 were confirmed by ultrasound. Plication of the diaphragm was performed in 30 patients (19%); compared with patients who did not undergo plication, these patients were younger (median age, 10 days vs 138 days; P < .001), more likely to have undergone deep hypothermic circulatory arrest (47% vs 18%; P = .005), had a longer duration of positive pressure ventilation (median, 15 days vs 7 days; P < .001), and had longer lengths of stay in both the intensive care unit (median, 23 days vs 8 days; P < .0001) and the hospital (median, 37 days vs 15 days; P < .0001). Early plication was associated with reduction in all intervals of care.

CONCLUSIONS

Early plication should be considered for patients with diaphragm paresis requiring prolonged respiratory support after cardiac bypass surgery. Longer follow-up evaluation is required to better define the long-term implications of plication.

Bilateral diaphragmatic palsy after congenital heart surgery: management options

Diaphragmatic paralysis following phrenic nerve injury is a major complication following congenital cardiac surgery. In contrast to unilateral paralysis, patients with bilateral diaphragmatic paralysis present a higher risk group, require different management methods, and have poorer prognosis. We retrospectively analysed seven patients who had bilateral diaphragmatic paralysis following congenital heart surgery during the period from July, 2006 to July, 2014. Considerations were given to the time to diagnosis of diaphragm paralysis, total ventilator days, interval after plication, and lengths of ICU and hospital stays. The incidence of bilateral diaphragmatic paralysis was 0.68% with a median age of 2 months (0.6-12 months). There was one neonate and six infants with a median weight of 4 kg (3-7 kg); five patients underwent unilateral plication of the paradoxical diaphragm following recovery of the other side, whereas the remaining two patients who did not demonstrate a paradoxical movement were successfully weaned from the ventilator following recovery of function in one of the diaphragms. The median ventilation time for the whole group was 48 days (20-90 days). The median length of ICU stay was 46 days (24-110 days), and the median length of hospital stay was 50 days (30-116 days). None of the patients required tracheostomy for respiratory support and there were no mortalities, although all the patients except one developed ventilator-associated pneumonia. The outcome of different management options for bilateral diaphragmatic paralysis following surgery for CHD is discussed.

Laparoscopic Diaphragmatic Hemiplication in Children with Acquired Diaphragmatic Eventration After Congenital Heart Surgery

PURPOSE

To report our technique and experiences in the laparoscopic diaphragmatic hemiplication (LDHP) in children with acquired diaphragmatic eventration after congenital heart surgery.

SUBJECTS AND METHODS

Between October 2007 to December 2013, 3498 children with congenital heart disease underwent cardiac surgery in our hospital, and 40 (1.14%) of them had unilateral diaphragmatic elevation on postoperative chest X-ray (mean elevation, 2.5 ± 0.26 intercostal spaces [ICS]) and were diagnosed as having diaphragmatic eventration due to diaphragmatic hemiparesis as a result of phrenic nerve injury. These 40 patients were followed up, and 22 of them recovered after conservative treatment; the other 18 needed surgical intervention. We conducted a retrospective study relating to surgical indications, surgical technique, complications, and outcomes.

RESULTS

There were 24 boys and 16 girls with a mean age of 10.0 ± 4.5 months old (range, 2 months-4 years). Twenty-two patients did not require surgical intervention. Eighteen patients underwent LDHP (12 cases left-sided and 6 cases right-sided); 2 of them had emergency LDHP with a history of ventilator dependency after cardiac surgery, and 16 of them had planned LDHP with a history of recurrent pneumonia and dyspnea. The operative time was 60 ± 7.9 minutes (range, 45-105 minutes), with minimal blood loss (3 ± 1.5 mL [range, 1-9 mL]), no intra- or postoperative complications, and postoperative hospital stay of 7 ± 1.3 days (range, 5-10 days). The diaphragmatic drop was 2.4 ± 0.2 (range, 2-4 ICS) without recurrence, and the follow-up time for all 40 patients was 14.8 ± 1.6 months (range, 11-36 months).

CONCLUSIONS

Our study further shows that LDHP is feasible and effective in selected patients after congenital heart surgery. Our technique is convenient and provides excellent clinical and radiological results.

Is sternotomy superior to thoracotomy for modified Blalock-Taussig shunt?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: is sternotomy approach superior to a thoracotomy approach for a modified Blalock-Taussig shunt procedure? More than 58 papers were found using the search as described below, of which 11 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. Three of seven papers compared the sternotomy and thoracotomy approaches. The operative approach was a significant predictor of shunt failure. The criterion used to define early shunt failure was either the complete occlusion during hospitalization or the need to return to the operating room for a second shunt. The studies that compared the thoracotomy and sternotomy approaches observed increased shunt failure rates in the thoracotomy group. The sternotomy approach was associated with advantages like less pulmonary artery distortion, ease of technical performance, cosmetic advantage of a single sternotomy incision, ease of ligation of patent ductus, less phrenic nerve injury, less collateral formation in chest wall adhesions and less thoracotomy induced scoliosis. However, other papers studied either the sternotomy approach only or the thoracotomy approach and drew conclusions regarding risk factors for operative morbidity and mortality. We conclude that the sternotomy approach is beneficial to neonates and infants undergoing modified Blalock-Taussig shunt when compared with the conventional thoracotomy approach.

Diaphragmatic Nerve Palsy After Cardiac Surgery in Children in Egypt

Introduction: Diaphragmatic paralysis (DP) due to phrenic nerve injury is a complication which occurs in association with congenital cardiac surgery and may be a life-threatening event in infants and young children. Information about this complication is still scarce from the developing countries. Methods: Retrospective study evaluated the incidence of DP among 414 patients who underwent congenital cardiac surgery in Abo Elriesh Children’s Specialized Hospital, Cairo University, Egypt, in the duration from April 2009 to December 2011. Results: Incidence of DP was 3.6% (15 of 414 cases). Median age of affected patients was 10 months (ranged from 1 month to 13 years). Diagnosis of DP was observed after ventricular septal defect repair (3.9%), Glenn anastomosis (8.6%), Tetralogy of Fallot repair (4.3%), Senning operation (10%), arterial switch operation (3.2%), Fontan procedure (33%), coarctation of the aorta repair (7%), and pulmonary artery banding (6.4%). Diaphragmatic plication was performed in 4 of 15 cases. Patients with DP had significantly prolonged mechanical ventilation duration as compared to unaffected patients (median 120, range 48-600 vs 4, range 0-48 hours, P < .000). They also had a higher incidence of nosocomial pneumonia in 8 of 15 (53%) cases, longer duration of intensive care unit stay (median 15, range 4-62 days, P < .006), and significant mortality in 7 of 15 (46%; P < .004). Mortality among patients who underwent diaphragm plication was 1 of 4 (25%). Conclusion: Diaphragmatic paralysis is a relatively rare complication of congenital cardiac surgery in children. Its occurrence is associated with increased morbidity and mortality. A high index of clinical suspicion, utilization of bedside diagnostic tools, and a policy of early plication for certain patients may lead to improved outcomes.

Diaphragmatic palsy after cardiac surgical procedures in patients with congenital heart

Paralysis of diaphragm on one or, exceptionally, both sides is a common cause of delayed recovery and excessive morbidity following pediatric cardiac surgery. The consequences of this complication after all forms of congenital heart surgery in newborns and young infants can be potentially serious. The impact of diaphragmatic palsy on the physiology after single ventricle palliations is particularly significant. It is necessary for all professionals taking care of children with heart disease to be familiar with the etiology, diagnosis, and management of this condition. Early recognition and prompt management of diaphragmatic palsy can potentially reduce the duration of mechanical ventilation and intensive care in those who develop this complication. This review summarizes the anatomy of the phrenic nerves, reasons behind the occurrence of diaphragmatic palsy, and suggests practical guidelines for management.

Catheters, wires, tubes and drains on postoperative radiographs of pediatric cardiac patients: the whys and wherefores

Surgical treatment of congenital heart disease has advanced dramatically since the first intracardiac repairs in the mid-20th century. Previously inoperable lesions have become the focus of routine surgery and patients are managed successfully in intensive care units around the world. As a result, increasing numbers of postoperative images are processed by departments of radiology in children's hospitals. It is important that the radiologist accurately documents and describes the catheters, wires, tubes and drains that are present on the chest radiograph. This article reviews the reasons for the placement and positioning of perioperative equipment in children who have surgical repair of atrial septal defect, ventricular septal defect or transposition of the great arteries. Also included are a brief synopsis of each cardiac anomaly, the surgical procedure for its correction, and an in-depth discussion of the postoperative chest radiograph including illustrations of catheters, wires, tubes and drains.

Subdiaphragmatic venous hemodynamics in patients with biventricular and Fontan circulation after diaphragm plication

OBJECTIVE

Diaphragm paralysis owing to phrenic nerve injury can result in significant morbidity in children undergoing surgical management of congenital cardiac defects. Diaphragm plication is the accepted therapy for diaphragm paralysis. We have investigated subdiaphragmatic venous hemodynamics in patients with biventricular and Fontan circulation after diaphragm plication.

METHODS

Doppler ultrasound was used to evaluate flows in the hepatic vein, portal vein, and subhepatic inferior vena cava under respiratory monitoring and with a tilt table. Twenty-nine patients with biventricular circulation were studied: 19 with normal diaphragms and 10 after diaphragm plication. Twenty-eight patients with total cavopulmonary connections after the Fontan procedure were also studied: 19 with normal diaphragms and 9 with plicated diaphragms. Inspiratory/expiratory flow ratios in supine and upright positions were calculated to investigate respiratory effects, and upright/supine flow ratios were calculated to assess gravity effects.

RESULTS

In patients with biventricular circulation and normal diaphragms, hepatic venous flow was augmented by inspiration; this effect was reduced in patients with a plicated diaphragm (upright inspiratory/expiratory flow ratios: 2.4 vs 1.4, respectively; P = .01). Portal venous flow was higher during expiration; this effect was lost in patients with a plicated diaphragm (supine inspiratory/expiratory flow ratios: 0.8 and 1.0; P < .05). In Fontan patients with normal diaphragms, hepatic venous flow depended heavily on inspiration. This effect was blunted in patients with a plicated diaphragm (supine inspiratory/expiratory flow ratios: 3.2 vs 2.3; P < .05). Expiratory augmentation of portal flow was absent in Fontan patients with normal diaphragms and reversed in patients a plicated diaphragm (supine inspiratory/expiratory flow ratios: 1.0 vs 1.6; P = .02). Gravity reduced Fontan portal venous flow; having a plicated diaphragm did not alter this effect (upright/supine flow ratios: 0.7 vs 0.7).

CONCLUSIONS

In patients with biventricular and those with Fontan circulation with a paralyzed diaphragm, plication does not completely restore normal subdiaphragmatic venous hemodynamics. In Fontan patients with a plicated diaphragm, important inspiration-derived hepatic venous flow is suppressed, and portal venous flow loses its normal expiratory augmentation. These flow dynamics share similarities with those observed in patients with failing Fontan circulation. This suboptimal splanchnic circulation may contribute to early problems of prolonged pleural effusions and ascites and potentially may promote late Fontan failure. Phrenic nerve injury should consequently be avoided at all costs before or at the time of the Fontan operation.