Diaphragm plication following phrenic nerve injury: a comparison of paediatric and adult patients

Management of Diaphragm Paralysis and Eventration

An elevated diaphragm may be due to eventration or paralysis. Diaphragm elevation is often asymptomatic and found incidentally on imaging. Fluoroscopic testing can be used to differentiate eventration (no paradoxic motion) from paralysis (paradoxic motion). Regardless of etiology, a diaphragm plication is indicated in all symptomatic patients with an elevated diaphragm. Plication can be approached either from a thoracic or abdominal approach, though most thoracic surgeons perform minimally invasive thoracoscopic plication. The goal of plication is to improve lung volumes and decrease paradoxic elevation of the hemidiaphragm. Diaphragm plication is safe, has excellent outcomes, and is associated with symptom improvement.

Iatrogenic eventration of the hemidiaphragm in a post-bariatric surgery patient

The aim of this report is to describe the management of an iatrogenic diaphragmatic eventration following surgery to relieve neurogenic symptoms of thoracic outlet syndrome in a patient with a prior history of sleeve gastrectomy. We discuss the case of a 46-year-old woman with a 6-month history of gastro-oesophageal reflux and dyspnoea. Imaging demonstrated a left hemidiaphragm eventration and hiatus hernia. The patient underwent laparoscopic plication of the left hemidiaphragm, repair of the hiatus hernia, and an omega loop gastric bypass, with satisfactory resolution of her symptoms. This demonstrates that surgical diaphragmatic plication has good outcomes in cases where the abdominal anatomy is already altered as a result of previous bariatric surgery, and that concurrent hiatus hernia repair, plication of iatrogenic diaphragm eventration, and sleeve to gastric bypass conversion satisfactorily relieve reflux and dyspnoea in a morbidly obese patient.

Quality-of-life impact of diaphragm plication in patients with diaphragmatic paralysis: A retrospective study

OBJECTIVES

While the overall incidence and prevalence of diaphragmatic paralysis are unknown due to a wide variety of underlying causes, symptomatic patients experience a marked decline in their quality of life. The goal of this study was to measure the impact of diaphragm plication surgery on the quality of life in patients who were diagnosed with diaphragmatic paralysis.

METHODS

A retrospective review of the medical records of 46 patients who underwent diaphragmatic plication surgery was performed. The review included patients who experienced unilateral and bilateral diaphragmatic paralysis. Patients who underwent repeat diaphragm plication surgery were also included in the study. Patients from the retrospective cohort were then contacted by telephone to answer the Dyspnea-12 (D-12) questionnaire. Patients were asked to recall the severity of their symptoms and quality of life preplication, 1-month postplication, and 6-month postplication. Severity of symptoms was ranked as either none, mild, moderate, or severe. Values were then assigned to each rank as follows: none = 0, mild = 1, moderate = 2, and severe = 3. Relative change and statistical significance were calculated with preplication measurements used as the baseline. Scores between preplication versus 1-month postplication and 6-month postplication were then compared by Student's paired t-test. All tests were two-sided and statistical significance was set at P < 0.05.

RESULTS

Forty-six patients were included in the study, from which 21 answered the D-12 questionnaire. Average scores from each component of the D-12 questionnaire showed improvement in the severity of symptoms from preplication to 1-month postplication. The latter period was then followed by continued improvement in all areas when symptoms 6-month postplication were assessed.

CONCLUSION

In patients with diaphragmatic paralysis, diaphragm plication was effective in reducing patients' symptoms while improving overall quality of life.

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.

Single port thoracoscopic diaphragm plication: A novel treatment approach to bilateral phrenic nerve palsy and diaphragm paralysis

INTRODUCTION AND IMPORTANCE

The diaphragm is the primary muscle of respiration. Bilateral paralysis of the diaphragm due to phrenic nerve palsy causes severe dyspnoea and is life threatening. Diaphragmatic Plication has shown great promise in treating diaphragm paralysis and has evolved as operative treatment from an open thoracotomy to multiport and robotic video assisted thoracoscopic surgery.

CASE PRESENTATION

Here we present a case of idiopathic bilateral diaphragm paralysis resulting significant deterioration in lung function tests, supplemental oxygen, and ventilator dependence. The patient was treated with a 2-stage operative plication of each hemidiaphragm through a 2.5 cm single incision thoracoscopic technique, which resulted in normalization of lung function tests, elimination of oxygen dependence and negligible analgesia requirements.

CASE DISCUSSION

This is the first case reported in the literature of a single port VATS plication of the diaphragm for the treatment of bilateral phrenic nerve palsy. Surgery, specifically diaphragm plication, is indicated for patients with significant symptoms and persistent paralysis. Video-assisted thoracoscopic surgery (VATS) has evolved from open operations to smaller incisions, offering improved lung function, postoperative pain, hospital stay, morbidity, and mortality.

CONCLUSION

Single port diaphragmatic plication is a novel approach to the treatment of bilateral phrenic nerve palsy. We make the case for indication of the technique for treatment of diaphragmatic paralysis.

Complicated intrathoracic tuberculosis: Role of therapeutic interventional bronchoscopy

In recent years bronchoscopy equipment has been improved with smaller instruments and larger size working channels. This has ensured that bronchoscopy offers both therapeutic and interventional options. As the experience of paediatric interventional pulmonologists continues to grow, more interventions are being performed. There is a scarcity of published evidence in the field of interventional bronchoscopy in paediatrics. This is even more relevant for complicated pulmonary tuberculosis (PTB). Therapeutic interventional bronchoscopy procedures can be used in the management of complicated tuberculosis, including for endoscopic enucleations, closure of fistulas, dilatations of bronchial stenosis and severe haemoptysis. Endoscopic therapeutic procedures in children with complicated TB may prevent thoracotomy. If done carefully these interventional procedures have a low complication rate.

Minimally Invasive Diaphragm Plication for Acquired Unilateral Diaphragm Paralysis: A Systematic Review

Objective: Diaphragm paralysis is a relatively uncommon entity that can be both congenital and acquired in nature. While commonly asymptomatic, it can also cause a significant decrease in pulmonary function and reserve, particularly in patients with underlying pulmonary diseases. Our aim was to summarize the current literature regarding the minimally invasive techniques used in the surgical correction of acquired diaphragm paralysis via traditional and robotic minimally invasive approaches. Methods: We conducted a systematic review of available literature using the Cochrane methodology and reported findings according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. Results: A total of 6,561 citations were identified through initial database and reference searches, of which 90 articles met the inclusion criteria for review. After further assessment, 33 appropriate full-text studies were selected for the review. Of the selected publications, the majority represented case reports and single-center retrospective studies with level of evidence 4. Only 1 level 2b study (individual cohort study) was identified, comparing minimally invasive and open approaches. Conclusions: Each of the minimally invasive approaches has its unique benefits and disadvantages, which are summarized and delineated in this article. Ultimately, no preferred method of diaphragm plication for diaphragm paralysis can be recommended at this time based on clinical data. The choice of procedure and surgical approach continues to be selected based on the surgeon's experience and preference.

A retrospective cohort study of idiopathic diaphragmatic palsy: a diagnostic triad, natural history and prognosis

Background

Isolated diaphragmatic palsy in the absence of progressive neuromuscular disease is uncommon. It poses diagnostic challenges and limited data are available regarding prognosis. We present retrospective cohort data from two large teaching hospitals in the United Kingdom.

Method

60 patients who were assessed either as inpatients or outpatients were included in this study. Patients with progressive neuromuscular disease were excluded. Clinical presentation, tests of respiratory muscle function (sitting/supine vital capacity, maximal expiratory pressure (MEP), maximal inspiratory pressure (MIP) and sniff nasal inspiratory pressure (SNIP)) and outcomes were recorded.

Results

For patients with diaphragmatic palsy, mean±sd seated and supine vital capacity pre-noninvasive ventilation (NIV) were reduced at 1.7±1.2 L and 1.1±0.9 L, respectively, with a mean±sd postural fall in vital capacity of 42±0.16%. The mean MEP/MIP and MEP/SNIP ratios for diaphragmatic palsy were 3 and 3.5, respectively. After a year of treatment with NIV, mean±sd upright and supine vital capacity had increased to 2.1±0.9 L and 1.8±1 L, respectively, and the mean±sd fall in vital capacity from sitting to supine reduced to 29±0.17%. MEP/MIP and MEP/SNIP ratios reduced to 2.6 and 2.9, respectively, from the pre-NIV values. The values of postural fall in vital capacity correlated (p<0.05) with MEP/MIP and MEP/SNIP ratio (r²=0.86 and r²=0.7, respectively).

Conclusion

Tests of respiratory muscle strength are valuable in the diagnostic workup of patients with unexplained dyspnoea. A triad of 1) orthopnoea, with 2) normal lung imaging and 3) MEP/MIP and/or MEP/SNIP ratio ≥2.7 points towards isolated diaphragmatic palsy. This needs to be confirmed by prospective studies.

Tests of respiratory muscle strength are valuable in the diagnostic workup of patients with unexplained dyspnoea. A triad of 1) orthopnoea with 2) normal lung imaging and 3) MEP/MIP and/or MEP/SNIP ratios ≥2.7 points towards isolated diaphragmatic palsy.https://bit.ly/2SpOXW2

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.

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.

Minimally Invasive Injection to the Phrenic Nerve in a Porcine Hemidiaphragmatic Paralysis Model: A Pilot Study

BACKGROUND

Neurodegenerative diseases and spinal cord injury can affect respiratory function often through motor neuron loss innervating the diaphragm. To reinnervate this muscle, new motor neurons could be transplanted into the phrenic nerve (PN), allowing them to extend axons to the diaphragm. These neurons could then be driven by an optogenetics approach to regulate breathing. This type of approach has already been demonstrated in the peripheral nerves of mice. However, there is no established thoracoscopic approach to PN injection. Also, there is currently a lack of preclinical large animal models of diaphragmatic dysfunction in order to evaluate the efficacy of potential treatments.

OBJECTIVE

To evaluate the feasibility of thoracoscopic drug delivery into the PN and to assess the viability of hemidiaphragmatic paralysis in a porcine model.

METHODS

Two Landrace farm pigs underwent a novel procedure for thoracoscopic PN injections, including 1 nonsurvival and 1 survival surgery. Nonsurvival surgery involved bilateral PN injections and ligation. Survival surgery included a right PN injection and transection proximal to the injection site to induce hemidiaphragmatic paralysis.

RESULTS

PN injections were successfully performed in both procedures. The animal that underwent survival surgery recovered postoperatively with an established right hemidiaphragmatic paralysis. Over the 5-d postoperative period, the animal displayed stable vital signs and oxygenation saturation on room air with voluntary breathing.

CONCLUSION

Thoracoscopic targeting of the porcine PN is a feasible approach to administer therapeutic agents. A swine model of hemidiaphragmatic paralysis induced by unilateral PN ligation or transection may be potentially used to study diaphragmatic reinnervation following delivery of therapeutics.

Thoracoscopic repair of diaphragmatic eventration in children: a comparison of two repair techniques

BACKGROUND

Thoracoscopic plication has gained popularity in the management of diaphragmatic eventration, and several suturing techniques have been described. However, the superiority of one technique over the other has not been demonstrated. The purpose of this study is to report our experience with diaphragmatic plication and to compare the thoracoscopic interrupted and pleated suture techniques in pediatric patients with diaphragmatic eventration.

METHODS

This is a retrospective cohort study (level of evidence: 3) performed on 14 patients with diaphragmatic eventration. All patients were symptomatic and had diaphragmatic plication via thoracoscopy. The patients were further divided into two groups according to the repair technique; interrupted repair (n = 9) and pleated repair (n = 5). Preoperative, operative and postoperative data were compared between the two groups.

RESULTS

The median age was 9.5 months (25th- 75th percentiles: 6 to 15 months), and 8 (57%) were males. Twelve patients (85.71%) had right side eventration, and nine patients (64.29%) had congenital diaphragmatic eventration. One case was converted to open thoracotomy because of adhesions. There was no difference in the preoperative characteristics between both groups. Median operative time was 117 min (25th- 75th percentiles: 101-129 min) and 77 min (25th- 75th percentiles: 73-83 min) in the interrupted and pleated groups, respectively (p = 0.004). One patient had a postoperative elevation of the diaphragm (incomplete repair) in the pleated group (p = 0.357). No recurrence was reported during the follow-up.

CONCLUSION

Thoracoscopic plication is an effective technique for management of diaphragmatic eventration in children. Pleating technique is easy, fast, and associated with a marked reduction in operative time.

TYPE OF THE STUDY

Retrospective cohort study.

LEVELS OF EVIDENCE

Level of evidence: 3.

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.

Diaphragmatic plication for iatrogenic respiratory insufficiency after cardiothoracic surgery

Background

The efficacy of diaphragmatic plication (DP) has been proven in many studies. However, there are few reports on DP for patients with severe respiratory conditions requiring mechanical ventilation. The study aim was to demonstrate the efficacy of DP for patients with severe respiratory insufficiency after cardiothoracic surgeries.

Methods

We retrospectively reviewed 10 patients who underwent DP for severe respiratory insufficiency due to postoperative diaphragmatic paralysis; eight of them required mechanical ventilation, and two needed high-flow oxygen therapy prior to DP. The symptoms, lung function, and elevation of the diaphragm were assessed before and after DP.

Results

All patients were successfully withdrawn from mechanical ventilation after DP and discharged without the need for oxygen therapy. The mean perioperative Medical Research Council (MRC) dyspnea scale (ATS/ERS 2004) score improved in 30 days (from 4 to 1.8) and in 90 days (from 4 to 0.6) after DP. Lung dynamic compliance was also ameliorated (mean improvement: 41.9 to 60.7 mL/cmH2O). Radiography revealed improved elevation of the diaphragm (mean improvement of 1.8 intercostal spaces, range, 1-2). Mean hospital stay after DP was 65.5 days (range, 25-187 days). One patient who underwent DP with endostapler-only suturing required re-operation because of staple line ruptures.

Conclusions

DP was found to be an effective form of treatment for patients with severe respiratory insufficiency after cardiothoracic surgery.

Diaphragmatic palsy after cardiac surgery in adult and pediatric patients

Background

Important differences in the mechanism of respiration between adults and children warrant distinction in the management of diaphragmatic paralysis as a complication of cardiac surgery. We describe the management and outcomes of this complication in both groups.

Methods

We retrospectively analyzed 16 patients (5 adults and 11 children) with diaphragmatic paralysis after cardiac surgery performed between 2008 and 2018. Clinical examination, chest radiography, and confirmation with fluoroscopy in selected cases were our modalities of diagnosis. All adults were managed conservatively, whereas plication was performed in all children.

Results

The incidence of diaphragmatic paralysis was 0.98% in pediatric patients and 0.43% in adults. The mean age was 2.33 ± 2.59 years in children and 53.2 ± 17.99 years in adults. All adults were symptomatic. All children showed difficulty in weaning from mechanical ventilation after cardiac surgery. The period of mechanical ventilation before plication was 2–6 days (median 4 days). Death occurred as a result of low cardiac output in a 10-year-old boy, and due to respiratory failure in a 30-year-old woman. Children were successfully weaned from mechanical ventilation after diaphragmatic plication. The median time to extubation after plication was 2.5 days (range 1–13 days). The median period of recovery in adults was 52 days (range 32–85 days). All survivors had acceptable outcomes at 6 months to one year.

Conclusion

Conservative management in adults and early plication in children are viable treatment options for diaphragmatic palsy after cardiac surgery, with acceptable outcomes.

Erb's palsy complicating a case of annular pancreas

We report an unusual presentation of annular pancreas with pneumoperitoneum in a newborn with an associated left sided Erb's palsy. The neurological deficit caused considerable confusion in the diagnosis and unexpected complications after surgery. We highlight the importance of clinical examination and the complications that an Erb's palsy can cause. This unusual triad of Erb's palsy, eventration of diaphragm and annular pancreas has hitherto not been described in literature.

Effect of Diaphragm Plication in Thymoma Patients with and without Myasthenia Gravis

BACKGROUND

Thymoma is the most common tumor of the anterior mediastinum that has the most effective treatment, as it can be completely resected. In patients with advanced stage, phrenic nerve involvement can be seen and suggested treatment for these patients is unilateral phrenic excision and diaphragm plication. However in patients with myasthenia gravis, there are concerns in relation to this method of treatment. The aim of this study is to evaluate the effects of plication of the diaphragm on complications of phrenic nerve excision in thymoma patients with and without myasthenia gravis involving the phrenic nerve.

MATERIALS AND METHODS

A retrospective cohort study was performed on 26 patients with thymoma; half of the patients had myasthenia gravis and the other half did not have myasthenia gravis. We performed diaphragm plication in 7 patients in each group with excision of phrenic nerve. Patients were evaluated based on preoperative and postoperative variables.

RESULTS

The patients' age (P=0.943), sex (P=0.999), blood loss during surgery (P=0.919), need for transfusion during surgery (P=0.999), short term complications (P=0.186), need for tracheostomy (P=0.27) and mortality (P=0.09) differences were not significant. However, the average duration of ICU stay (P=0.001) and intubation in ICU (P=0.001) in patients who had myasthenia gravis was more than patients without myasthenia gravis. These values were less in patients with myasthenia gravis and diaphragm plication than patients with myasthenia gravis and no diaphragm plication.

CONCLUSION

Excision of the phrenic nerve in patients with myasthenia gravis associated with thymoma and phrenic nerve involvement is appropriate.

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.

Best Approach and Benefit of Plication for Paralyzed Diaphragm

Diaphragmatic eventration and diaphragmatic paralysis are 2 entities with different etiology and pathology, and are often clinically indistinguishable. When symptomatic, their treatment is the same, with the objective to reduce the dysfunctional cephalad excursion of the diaphragm during inspiration. This can be achieved with diaphragmatic plication through the thorax or the abdomen with either open or minimally invasive techniques. We prefer the laparoscopic approach, due to its easy access to the diaphragm and to avoid pain associated with intercostal incisions and instrument use. Short-term and long-term results are excellent with this technique.

Risk Factors for post-Cardiac Surgery Diaphragmatic Paralysis in Children with Congenital Heart Disease

BACKGROUND

Injured phrenic nerve secondary to cardiac surgeries is the most common cause of diaphragmatic paralysis (DP) in infants. The aim of this study was to determine the risk factors for DP caused by congenital heart defect corrective surgeries in pediatrics.

METHODS

This cross-sectional study, conducted in a 2-year period (2006-2008), included 451 children with congenital heart diseases admitted to the Pediatric Cardiac Surgery Ward of Imam Khomeini Hospital. The diaphragmatic function was examined via fluoroscopy, and the frequency of DP and its relevant parameters were evaluated.

RESULTS

Of the 451 patients, comprising 268 males and 183 females at an age range of 3 days to 204 months (28.2 ± 33.4 months), 25 (5.5%) infants (60% male and 40% female, age range = 15 days to 132 months, 41.2 ± 28.1 months) had DP as follows: 48% unilateral right-sided and 36% unilateral left-sided. Additionally, 68% had cyanotic congenital heart disease and 84% had DP following total correction surgery. The highest prevalence rates of DP resulting in phrenic hemiparesis were observed after arterial switch operation, Fontan procedure, and Blalock-Taussig shunt surgery, respectively. Thirteen (52%) of the 25 DP patients underwent surgical diaphragmatic plication because of severe respiratory distress and dependency on mechanical ventilation, and most of the cases of plication underwent arterial switch operation. The rate of mortality was 24% (6 patients).

CONCLUSION

DP with a prevalence of 5.5% was one of the most common complications secondary to cardiac surgeries in the infants included in the present study. Effective factors were age, weight, cyanotic congenital heart defects, and previous cardiac surgery. Diaphragmatic plication improved prognosis in severe cases.

[Thoraco-abdomino-pelvic surgery for tumors in children: Postoperative sequelae]

Thoracic surgery for pediatric tumors may induce a large variety of sequelae that mainly concern skin, muscles and bones (ribs), thoracic nerve and spinal cord and respiratory system. Muscle-sparing thoracotomy, intrathoracic expanders inserted after right pneumonectomy, early orthopedic evaluation and follow-up are useful preventive proceedings able to decrease postoperative sequelae. Surgery for abdominal tumors in children is part of a sequence where each therapeutic treatment can induce its own sequelae possibly potentiated by other therapies. Scars and occlusions represent classic effects, others like diarrhea, intestinal ischemia may require specific and sometimes partially effective long-term treatment. The pelvic cavity is characterized by an anatomy dedicated to urinary and digestive continence and reproductive functions. The oncologic resection of tumors developed in this region exposed to significant risk of sequelae that may strongly affect the quality of life. The development of conservative approaches for local treatment and of fertility preservation techniques has significantly reduced this morbidity and must be known by the surgeon to optimize the therapeutic strategy.

Chitosan tubes can restore the function of resected phrenic nerves

OBJECTIVES

We previously reported that the phrenic nerve could be morphologically repaired by implantation of a chitosan nanofibre tube (C-tube). In the current study, we investigated whether implantation of C-tubes could improve the function of an injured phrenic nerve using a beagle dog model.

METHODS

Seven beagle dogs underwent right thoracotomy under general anaesthesia. An approximately 5 mm length of the right phrenic nerve was resected. Five dogs had a C-tube implantation (C-tube group) and other two dogs did not have the C-tube implantation (control group). Diaphragm movements were longitudinally measured by X-ray fluoroscopy before surgery, immediately after the surgery, and 3, 6 and 12 months after the surgery. The diaphragm movement was determined by diaphragm levels at inspiration and expiration phases, and the excursion difference between them was calculated. At 12 months after the surgery, rethoracotomy was performed to examine electrical phrenic nerve conduction. The C-tube and phrenic nerve were then excised for histological assessment of nerve regeneration.

RESULTS

Three of the five animals of the C-tube group showed improvement of diaphragm movement with time. In these three animals, slow phrenic nerve conduction was observed. Histological assessment showed that the injured nerve was connected by newly regenerating nerve fibres surrounded by granulation tissue within the C-tube. On the other hand, the animals in the control group and two animals of the C-tube group showed neither improved diaphragm movement, nor electrical conduction to the diaphragm. No nerve fibre regeneration was found by histology.

CONCLUSIONS

Our results suggest that, in addition to morphological improvement, C-tube implantation can functionally improve the injured phrenic nerve by promoting phrenic nerve regeneration.

Exercise therapy for a patient with persistent dyspnea after combined traumatic diaphragmatic rupture and phrenic nerve injury

We present a case report of a patient with a history of diaphragmatic rupture who had persistent dyspnea for 9 months after primary surgical repair of a right diaphragmatic rupture caused by a car accident. A phrenic nerve conduction study was performed, which demonstrated a rare accompanying ipsilateral phrenic nerve injury with resultant hemidiaphragmatic paralysis. Aerobic exercise therapy for the purpose of improving endurance and dietary modification for weight reduction were prescribed and continued for 6 months. The exercise intensity was prescribed based on the percentage of maximum heart rate as confirmed by an exercise tolerance test. The duration of exercise was gradually increased. In this case, the long-persistent dyspnea was successfully alleviated via nonoperative management to the point that the patient could resume regular activities of daily living.

Is video-assisted thoracoscopic diaphragmatic plication a widespread technique for diaphragmatic hernia in adults? Review of the literature and results of a national survey

Diaphragmatic plication is the most accepted treatment for symptomatic diaphragmatic hernia in adults. The fact that this pathology is infrequent and this procedure not been widespread means that this is an exceptional technique in our field. To estimate its use in the literature, we carried out a review in English and Spanish, to which we added our series. We found only six series that contribute 59 video-assisted mini-thoractomy for diaphragmatic plications in adults, and none in Spanish. Our series will be the second largest with 18 cases. Finally, we conducted a survey in all the Spanish Thoracic Surgery units in Spain: none reported more than 10 cases operated by thoracoscopy in the last 8 years (except our series) and most continue employing thoracotomy as the main approach. We believe that many patients with symptomatic diaphragmatic hernia could benefit from the use of such techniques.

[Diaphragmatic palsy and dysfunction: from physiology to surgery]

The clinical presentations of diaphragm dysfunctions vary according to etiologies and unilateral or bilateral diseases. Elevation of the hemidiaphragm from peripheral origins, the most frequent situation, requires a surgical treatment only in case of major functional impact. Complete morphological and functional analyses of the neuromuscular chain and respiratory tests allow the best selection of patients to be operated. The surgical procedure may be proposed only when the diaphragm dysfunction is permanent and irreversible. Diaphragm plication for eventration through a short lateral thoracotomy, or sometimes by videothoracoscopy, is the only procedure for retensioning the hemidiaphragm. This leads to a decompression of intrathoracic organs and a repositioning of abdominal organs without effect on the hemidiaphragm active contraction. Morbidity and mortality rates after diaphragm plication are very low, more due to the patient's general condition than to surgery itself. Functional improvements after retensioning for most patients with excellent long-term results validate this procedure for symptomatic patients. In case of bilateral diseases, very few bilateral diaphragm plications have been reported. Some patients with diaphragm paralyses from central origins become permanently dependent on mechanical ventilation whereas their lungs, muscles and nerves are intact. In patients selected by rigorous neuromuscular tests, a phrenic pacing may be proposed to wean them from respirator. Two main indications have been validated: high-level tetraplegia above C3 and congenital alveolar hypoventilation from central origin. After progressive reconditioning of the diaphragm muscles following phrenic pacing at thoracic level, more than 90% of patients can be weaned from respirator within a few weeks. This weaning improves the quality of life with more physiological breathing, restored olfaction, better sleep and better speech. The positive impact of diaphragm stimulation has also been evaluated in other degenerative neurological diseases, particularly the amyotrophic lateral sclerosis. For either central or peripheral diaphragm dysfunctions, a successful surgical treatment lies on a strict preoperative selection of patients.

Early hemi-diaphragmatic plication through a video assisted mini-thoracotomy in postcardiotomy phrenic nerve paresis

New symptom onset of respiratory distress without other cause, and new hemi-diaphragmatic elevation on chest radiography postcardiotomy, are usually adequate for the diagnosis of phrenic nerve paresis. The symptom severity varies (asymptomatic state to severe respiratory failure) depending on the degree of the lesion (paresis vs. paralysis), the laterality (unilateral or bilateral), the age, and the co-morbidity (respiratory, cardiac disease, morbid obesity, etc). Surgical treatment (hemi-diaphragmatic plication) is indicated only in the presence of symptoms. The established surgical treatment is plication of the affected hemidiaphragm which is generally considered safe and effective. Several techniques and approaches are employed for diaphragmatic plication (thoracotomy, video-assisted thoracoscopic surgery, video-assisted mini-thoracotomy, laparoscopic surgery). The timing of surgery depends on the severity and the progression of symptoms. In infants and young children with postcardiotomy phrenic nerve paresis the clinical status is usually severe (failure to wean from mechanical ventilation), and early plication is indicated. Adults with postcardiotomy phrenic nerve paresis usually suffer from chronic dyspnoea, and, in the absence of respiratory distress, conservative treatment is recommended for 6 months -2 years, since improvement is often observed. Nevertheless, earlier surgical treatment may be indicated in non-resolving respiratory failure. We present early (25(th) day postcardiotomy) right hemi-diaphragm plication, through a video assisted mini-thoracotomy in a high risk patient with postcardiotomy phrenic nerve paresis and respiratory distress. Early surgery with minimal surgical trauma, short operative time, minimal blood loss and postoperative pain, led to fast rehabilitation and avoidance of prolonged hospitalization complications. The relevant literature is discussed.

Can lung volumes and capacities be used as an outcome measure for phrenic nerve recovery after cardiac surgeries?

Phrenic nerve is the main nerve drive to the diaphragm and its injury is a well-known complication following cardiac surgeries. It results in diaphragmatic dysfunction with reduction in lung volumes and capacities. This study aimed to evaluate the objectivity of lung volumes and capacities as an outcome measure for the prognosis of phrenic nerve recovery after cardiac surgeries. In this prospective experimental study, patients were recruited from Cardio-Thoracic Surgery Department, Educational-Hospital of College of Medicine, Cairo University. They were 11 patients with right phrenic nerve injury and 14 patients with left injury. On the basis of receiving low-level laser irradiation, they were divided into irradiated group and non-irradiated group. Measures of phrenic nerve latency, lung volumes and capacities were taken pre and post-operative and at 3-months follow up. After 3 months of low-level laser therapy, the irradiated group showed marked improvement in the phrenic nerve recovery. On the other hand, vital capacity and forced expiratory volume in the first second were the only lung capacity and volume that showed improvement consequent with the recovery of right phrenic nerve (P value <0.001 for both). Furthermore, forced vital capacity was the single lung capacity that showed significant statistical improvement in patients with recovered left phrenic nerve injury (P value <0.001). Study concluded that lung volumes and capacities cannot be used as an objective outcome measure for recovery of phrenic nerve injury after cardiac surgeries.

Long-term results of diaphragmatic plication in adults with unilateral diaphragm paralysis

BACKGROUND

In this study we aimed to evaluate the long-term outcome of diaphragmatic plication for symptomatic unilateral diaphragm paralysis.

METHODS

Thirteen patients who underwent unilateral diaphragmatic plication (2 patients had right, 11 left plication) between January 2003 and December 2006 were evaluated. One patient died postoperatively due to sepsis. The remaining 12 patients [9 males, 3 females; mean age 60 (36-66) years] were reevaluated with chest radiography, flouroscopy or ultrasonography, pulmonary function tests, computed tomography (CT) or magnetic resonance imaging (MRI), and the MRC/ATS dyspnea score at an average of 5.4 (4-7) years after diaphragmatic plication.

RESULTS

The etiology of paralysis was trauma (9 patients), cardiac by pass surgery (3 patients), and idiopathic (1 patient). The principle symptom was progressive dyspnea with a mean duration of 32.9 (22-60) months before surgery. All patients had an elevated hemidiaphragm and paradoxical movement radiologically prior to surgery. There were partial atelectasis and reccurent infection of the lower lobe in the affected side on CT in 9 patients. Atelectasis was completely improved in 9 patients after plication. Preoperative spirometry showed a clear restrictive pattern. Mean preoperative FVC was 56.7 ± 11.6% and FEV1 65.3 ± 8.7%. FVC and FEV1 improved by 43.6 ± 30.6% (p < 0.001) and 27.3 ± 10.9% (p < 0.001) at late follow-up. MRC/ATS dyspnea scores improved 3 points in 11 patients and 1 point in 1 patient at long-term (p < 0.0001). Eight patients had returned to work at 3 months after surgery.

CONCLUSIONS

Diaphragmatic plication for unilateral diaphragm paralysis decreases lung compression, ensures remission of symptoms, and improves quality of life in long-term period.

Right phrenic nerve injury as a complication of tracheoesophageal fistula repair

OBJECTIVE

To report a rare case of right hemidiaphragmatic paralysis after tracheoesophageal fistula repair, and successful nonoperative management.

DESIGN

Case report and literature review.

SETTING

Pediatric intensive care unit in an academic, tertiary care medical center.

PATIENT

A neonate born to a G1P1Ab0 mother was diagnosed with tracheoesophageal fistula in the immediate postnatal period. He underwent gastrostomy and colostomy with mucous fistula on day 1 of life, and definitive repair of his esophageal atresia and tracheoesophageal fistula via a right posterolateral thoracotomy and a retropleural approach on day 6 of life. The patient failed several attempts at postoperative extubation, and a radiograph on day 11 of life revealed a persistently elevated right hemidiaphragm.

INTERVENTION

Nonoperative management with noninvasive positive-pressure ventilation.

MEASUREMENTS AND MAIN RESULTS

Restoration of normal diaphragmatic motion.

CONCLUSIONS

This case highlights two important points to be considered when tracheoesophageal fistula repair is performed in infants. First, phrenic nerve injury should be included in the differential diagnosis of any patient who has difficulty being weaned from the ventilator in the postoperative period after tracheoesophageal fistula repair. Second, when paralysis of the hemidiaphragm does occur, patients should receive an initial trial of nonoperative management, with diaphragmatic plication reserved for those patients who fail to regain diaphragmatic function after 4 to 6 wks.

Diaphragm plication for eventration or paralysis: a review of the literature

Although etiology and pathology of symptomatic diaphragm paralysis and eventration are distinct, their treatments are the same: to reduce dysfunctional caudal excursion of the diaphragm during inspiration by plication. Minimally invasive diaphragm plication techniques have emerged as equally effective and less morbid alternatives to open plication. This review focuses on the etiology, pathophysiology, diagnosis, and treatment of diaphragmatic eventration or paralysis in adults.

[Surgical treatment of diaphragmatic eventrations and paralyses]

Surgical treatment of eventration or paralysis of the diaphragm is symptomatic and non curative, and depends on whether the dysfunction is of peripheral or central origin. Elevation of a hemidiaphragm of peripheral origin, the most frequent situation, needs surgical treatment only in case of major functional effects (effort or positional dyspnoea, cardiac or digestive symptoms, or pain) that persists despite optimal conservative management. Selection of candidates for surgery depends on a thorough morphological and functional investigation of the neuromuscular and respiratory components. Surgical plication of the diaphragm through a lateral thoracotomy or by video-thoracoscopy is a recognized, safe and effective procedure. Its low morbidity and mortality, which are mainly associated with co-morbid factors, and its long-lasting functional benefit of around 100%, show that it is an effective procedure. In the case of bilateral dysfunction, occasional cases of bilateral plication have been reported. Some cases of diaphragmatic paralysis of central causation result in a life of ventilator dependence, even though the peripheral neuromuscular and respiratory systems are intact. In selected cases, following a complete functional investigation, phrenic nerve pacing may be attempted to achieve ventilator weaning. To date, there are two validated indications for this technique: Tetraplegia above C3 and alveolar hypoventilation of central cause. After thoracic implantation, a progressive reconditioning of the diaphragmatic muscle allows weaning from the ventilator in a few weeks in more than 90% of patients. Their quality of life is greatly improved thanks to independence from the ventilator, more physiological respiration, restoration of smell and better speech. Whether the diaphragmatic dysfunction is peripheral or central in origin, the success of surgical treatment depends on rigorous preoperative selection of patients.

Diaphragmatic paralysis associated with neonatal brachial plexus palsy

Phrenic nerve palsy can occur in the context of neonatal brachial plexus palsy, yet neither outcomes nor definitive treatment guidelines have been established. Diaphragmatic paralysis alone in the newborn results in significant respiratory sequelae and failure to thrive. Reviewing the available literature revealed little information about the incidence of phrenic nerve palsy associated with neonatal brachial plexus palsy, or whether outcomes are associated with the severity of the brachial plexus palsy. Of patients with brachial plexus palsy evaluated during 2005-2009 (n = 166) at our institution, a minority (2.4%; n = 4) had clinically significant diaphragmatic palsy. Of these, a majority (75%; n = 3) manifested respiratory complications sufficient to warrant diaphragmatic plication. The severity of brachial plexus palsy failed to correlate with severity of respiratory consequences. None of the patients underwent nerve repair or reconstruction. We suggest that diaphragmatic paralysis should not be overlooked during a brachial plexus examination, and diaphragmatic paralysis in the very young may require aggressive intervention before the treatment of brachial plexus palsy.

Diaphragmatic eventration

Symptomatic diaphragmatic eventration is an uncommon condition and is sometimes impossible to distinguish clinically from paralysis. Patients who are asymptomatic require no treatment; patients who are symptomatic benefit significantly from diaphragm plication. The choice of plication approach is dependent upon the expertise of the surgeon.

The Phrenic Nerve And Atrial Fibrillation Ablation Procedures

Radiofrequency ablation is increasingly used as an option to optimally manage patients with symptomatic atrial fibrillation. Presently, ablationists strive to improve success rates, particularly with persistent atrial fibrillation, while simultaneously attempting to reduce complications. A well-recognized complication with atrial fibrillation ablation is injury to the phrenic nerve giving rise to diaphragmatic paresis and patient discomfort.Phrenic nerve damage may occur when performing common components of atrial fibrillation ablation including pulmonary and superior vena caval isolation. The challenge for ablationists is to successfully target the arrhythmogenic substrate while avoiding this complication. In order to do this, a thorough knowledge of phrenic nerve anatomy, points in the ablation procedure where nerve damage is more likely, and an understanding of the presently utilized techniques to avoid this complication is required. In addition, when this complication does arise, prompt recognition of its occurrence, knowledge of the natural history, and available methods for management are needed.In this review, we discuss the underlying anatomic principles, techniques of avoiding phrenic nerve damage, and presently available methods of diagnosing and managing this complication.

Phrenic nerve palsy in children associated with confirmed intrathoracic tuberculosis: diagnosis and clinical course

In this descriptive retrospective cases series of eight cases phrenic nerve palsy in children caused by tuberculosis lymph gland infiltration of the phrenic nerve. The lymph gland enlargement was in all cases caused by culture confirmed Mycobacterium tuberculosis. The phrenic nerve palsy was on the left side in all eight cases with the presenting feature a raised diaphragm on chest radiography that was accompanied by consolidation of the left upper lobe (88%) The diagnosis of phrenic nerve palsy was confirmed by fluoroscopy of the chest. On computer tomography the outstanding features were left sided hilar and paratracheal lymph gland enlargement with displacement of the mediastinum to the right. Mediastinal displacement lead to anterior displacement of the descending aorta, which further compressed the left main bronchus. Two children had accompanying respiratory failure requiring assisted ventilation and in two additional cases the airway compression was so severe that glandular enucleation of the enlarged glands was indicated. Of the eight children five remained symptomatic after completion of TB treatment to which steroids were added for the initial month. Diaphragmatic plication was indicated in all five cases. On clinical follow-up two children had repeated respiratory tract infections secondary to underlying lung damage while the other six remained asymptomatic.

Long-term non-invasive positive airway pressure ventilation in infants

AIM

To evaluate the clinical application of long-term non-invasive ventilation (NIV) in infants with life-threatening ventilatory failure with regard to: diagnosis, age at initiation, indication for and duration of treatment, clinical outcome and mortality and adverse effects.

PATIENTS AND METHODS

The medical records of 18 infants treated in a home setting during a 7-year period were reviewed. The criteria for ventilatory support were: (a) transcutaneous partial pressures of carbon dioxide (TcPCO(2)) >6.5 kPa and oxygen (TcPO(2)) < 8.5 kPa and (b) decreased cough ability and/or recurrent chest infections.

RESULTS

The median age at initiation was 4 months (range 1-12). NIV was initiated because of hypoventilation in 12 infants and because of reduced cough ability and/or recurrent infections in six infants. Tracheotomy was eventually needed in two infants. The median duration of treatment was 24 months (range 1-84). NIV produced significant improvements, with median TcPCO(2) falling from 9.9 to 6.1 kPa, and median TcPO(2) rising from 9.8 to 11.1 kPa.

CONCLUSION

NIV can be successfully and safely used in infants with prolonged life-threatening ventilatory failure, potentially avoiding intubation and tracheotomy.

Diaphragm plication in adult patients with diaphragm paralysis leads to long-term improvement of pulmonary function and level of dyspnea

OBJECTIVE

There is still controversy about the feasibility and long-term outcome of surgical treatment of acquired diaphragm paralysis. We analyzed the long-term effects on pulmonary function and level of dyspnea after unilateral or bilateral diaphragm plication.

METHODS

Between December 1996 and January 2006, 22 consecutive patients underwent diaphragm plication. Before surgery, spirometry in both seated and supine positions and a Baseline Dyspnea Index were assessed. The uncut diaphragm was plicated as tight as possible through a limited lateral thoracotomy. Patients with a follow-up exceeding 1 year (n=17) were invited for repeat spirometry and assessment of changes in dyspnea level using the Transition Dyspnea Index (TDI).

RESULTS

Mean follow-up was 4.9 years (range 1.2-8.7). All spirometry variables showed significant improvement. Mean vital capacity (VC) in seated position improved from 70% (of predicted value) to 79% (p<00.03), and in supine position from 54% to 73% (p=0.03). Forced expiratory volume in 1s (FEV1) in supine position improved from 45% to 63% (p=0.02). Before surgery the mean decline in VC changing from seated to supine position was 32%. At follow-up this had improved to 9% (p=0.004). For FEV1 these values were 35% and 17%, respectively (p<0.02). TDI showed remarkable improvement of dyspnea (mean+5.69 points on a scale of -9 to +9).

CONCLUSION

Diaphragm plication for single- or double-sided diaphragm paralysis provides excellent long-term results. Most patients were severely disabled before surgery but could return to a more or less normal way of life afterwards.

[Thoracic surgery in solving enormous elevation of the left hemidiaphragm]

BACKGROUND

Acquired elevation of the diaphragm is mostly the result of phrenic nerve paralysis, some of thoracic and abdominal patological states, and also some of neuromuscular diseases. Surgical treatment is rarely performed and is indicated when lung compression produces disabilitating dyspnea, and includes plication of diaphragm. The goal of this case report has been to show completely documented diagnostic procedures and surgical treatment one of rare pathological condition.

CASE REPORT

A 62-year-old patient was admitted to our clinic because of surgical treatment of the enormous elevation of the left hemidiaphragm. After thoracotomy and plication of the bulging diaphragm, lung compression did not exist any more and mediastinum went back in the normal position.

CONCLUSION

Elevation of the diaphragm rarely demands surgical correction. When it is complicated with lung compression and disabilitating dyspnea, surgical treatment has extremely useful functional effect.

Experimental repair of phrenic nerve using a polyglycolic acid and collagen tube

OBJECTIVE

The feasibility of a nerve guide tube for regeneration of the phrenic nerve with the aim of restoring diaphragmatic function was evaluated in a canine model.

METHODS

The nerve tube, made of woven polyglycolic acid mesh, had a diameter of 3 mm and was filled with collagen sponge. This polyglycolic acid-collagen tube was implanted into a 10-mm gap created by transection of the right phrenic nerve in 9 beagle dogs. The tubes were implanted without a tissue covering in 5 of the 9 dogs (group I), and the tubes were covered with a pedicled pericardial fat pad in 4 dogs (group II). Chest x-ray films, muscle action potentials, and histologic samples were examined 4 to 12 months after implantation.

RESULTS

All of the dogs survived without any complications. x-ray film examination showed that the right diaphragm was paralyzed and elevated in all dogs until 3 months after implantation. At 4 months, movement of the diaphragm in the implanted side was observed during spontaneous breathing in 1 dog of group I and in 3 dogs of group II. In the dogs showing diaphragm movement, muscle action potentials were evoked in the diaphragm muscle, indicating restoration of nerve function. Regeneration of the phrenic nerve structure was also examined on the reconstructed site using electron microscopy.

CONCLUSION

The polyglycolic acid-collagen tube induced functional recovery of the injured phrenic nerve and was aided by coverage with a pedicled pericardial fat pad.

Nerve Injury: Injury to the Recurrent Laryngeal, Phrenic, Vagus, Long Thoracic, and Sympathetic Nerves During Thoracic Surgery

Nerve injury occurs in about 1% of patients undergoing thoracic surgery. Most commonly, it is the result of surgical trauma specific to the area of operation. Alternatively, it may be due to retraction on adjacent structures during the exposure of complex surgical procedures. This article reviews the most common types of nerve injury and discusses the pathophysiology, etiology, diagnosis, and treatment of each.

Abdominal Compartment Syndrome: A Rare Complication of Plication of the Diaphragm

Abdominal compartment syndrome is an increasingly recognized phenomenon. We report the case of an otherwise fit and healthy 42-year-old man who underwent plication of the right hemidiaphragm for idiopathic phrenic paresis. His postoperative recovery was complicated by abdominal compartment syndrome, which was managed conservatively. We believe this is the only report of this complication after diaphragmatic plication and one of very few reported thoracic causes of abdominal compartment syndrome.

Functional and Physiologic Results of Video-Assisted Thoracoscopic Diaphragm Plication in Adult Patients With Unilateral Diaphragm Paralysis

BACKGROUND

Plication of the hemidiaphragm for unilateral diaphragm paralysis is infrequently performed in adults. Barriers to diaphragm plication have included the perceived need for thoracotomy and uncertainty of the potential benefits. The purpose of this investigation was to assess the effects of video-assisted thoracoscopic diaphragm plication in symptomatic adult patients with unilateral diaphragm paralysis.

METHODS

Patients with unilateral diaphragm paralysis underwent an evaluation that included a chest radiograph, fluoroscopic sniff test, pulmonary spirometry, and the Medical Research Council (MRC) dyspnea score. Patients with symptomatic unilateral diaphragm paralysis present for at least 6 months were offered video-assisted thoracoscopic diaphragm plication. Patients who underwent diaphragm plication as well as those who declined surgery were reassessed at 6 months with a chest radiograph, spirometry, and the MRC dyspnea score.

RESULTS

Twenty-five patients underwent left (19) or right (6) diaphragm plication through video-assisted thoracoscopic diaphragm plication (22) or thoracotomy (3). There were no operative deaths. Mean hospital length of stay for diaphragm plication was 3.7 days for video-assisted thoracoscopic diaphragm plication and 5.4 days for thoracotomy. After diaphragm plication, mean forced vital capacity, forced expiratory volume at 1 second, functional residual capacity, and total lung capacity improved by 17%, 21.4%, 20.3%, and 16.1%, respectively (p < 005) at 6 months. Mean MRC dyspnea scores also significantly improved in the operative cohort (p < 0001). Seventeen patients in the surgical cohort had returned to work at 6 months. Seven patients treated without surgery displayed a trend toward more frequent hospitalizations and deteriorating pulmonary spirometry and MRC dyspnea scores during the follow-up period.

CONCLUSIONS

Plication of the hemidiaphragm using minimally invasive techniques produced significant improvements in patients' functional status, pulmonary spirometry, and MRC dyspnea scores. Video-assisted thoracoscopic diaphragm plication should be considered appropriate therapy in symptomatic adult patients with unilateral diaphragm paralysis.

Respiratory inductance plethysmography used to diagnose bilateral diaphragmatic paralysis: a case report

OBJECTIVE

To report the use of respiratory inductance plethysmography in the diagnosis and management for a case of bilateral diaphragmatic paralysis after repeated sternotomies in a 23-month-old child.

DESIGN

Case report.

SETTING

A 15-bed pediatric cardiothoracic intensive care unit in an academic children's hospital.

INTERVENTIONS

The patient could not be weaned from the ventilator after a repeat sternotomy for pulmonary artery reconstruction. Pulmonary function test results were within normal limits, and plain film radiography, ultrasonography, and fluoroscopy were unable to establish a definitive diagnosis. Evaluation of thoracoabdominal synchrony was undertaken using respiratory inductance plethysmography (RespiTrace). The work of breathing was assessed using esophageal manometry to obtain the pressure-rate product.

RESULTS

During spontaneous breathing, complete thoracoabdominal asynchrony was noted, with clockwise Konno-Mead loops and associated phase angles of nearly 180 degrees. The pressure-rate product was 120 cm H(2)O/min, indicating elevated work of breathing. The pressure-rate product decreased dramatically, as indicated by measurement and observation, in response to increased levels of continuous positive airway pressure.

CONCLUSIONS

The diagnosis of bilateral diaphragmatic paralysis can be confirmed by measurement of thoracoabdominal synchrony. Therapeutic and diagnostic application of continuous positive airway pressure may predict response to diaphragmatic plication. Controlled trials comparing measurement of thoracoabdominal synchrony with standard methods for the early diagnosis of diaphragmatic paralysis are needed.

Disorders of the respiratory muscles

The act of breathing depends on coordinated activity of the respiratory muscles to generate subatmospheric pressure. This action is compromised by disease states affecting anatomical sites ranging from the cerebral cortex to the alveolar sac. Weakness of the respiratory muscles can dominate the clinical manifestations in the later stages of several primary neurologic and neuromuscular disorders in a manner unique to each disease state. Structural abnormalities of the thoracic cage, such as scoliosis or flail chest, interfere with the action of the respiratory muscles-again in a manner unique to each disease state. The hyperinflation that accompanies diseases of the airways interferes with the ability of the respiratory muscles to generate subatmospheric pressure and it increases the load on the respiratory muscles. Impaired respiratory muscle function is the most severe consequence of several newly described syndromes affecting critically ill patients. Research on the respiratory muscles embraces techniques of molecular biology, integrative physiology, and controlled clinical trials. A detailed understanding of disease states affecting the respiratory muscles is necessary for every physician who practices pulmonary medicine or critical care medicine.