© 2005 WebMD, Inc. All rights reserved.                                                       ACS Surgery: Principles and ...
© 2005 WebMD, Inc. All rights reserved.                                                  ACS Surgery: Principles and Pract...
© 2005 WebMD, Inc. All rights reserved.                                                      ACS Surgery: Principles and P...
© 2005 WebMD, Inc. All rights reserved.                                                   ACS Surgery: Principles and Prac...
© 2005 WebMD, Inc. All rights reserved.                                                    ACS Surgery: Principles and Pra...
© 2005 WebMD, Inc. All rights reserved.                                                      ACS Surgery: Principles and P...
© 2005 WebMD, Inc. All rights reserved.                                                                            ACS Sur...
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Acs0406 Paralyzed Diaphragm

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  1. 1. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 1 6 PARALYZED DIAPHRAGM Bryan F Meyers, M.D., F.A.C.S., and Benjamin D. Kozower, M.D. . Evaluation of Elevated Hemidiaphragm Paralysis of the diaphragm is an unusual and challenging clinical compromise. Patients may sleep in a semirecumbent position or in problem that may occur either in isolation or as part of a systemic the lateral decubitus position with the affected hemidiaphragm disease. It can be caused by a number of disorders and should be down. Most patients have few respiratory symptoms at rest, but considered in the differential diagnosis whenever a chest radi- some complain of dyspnea, cough, or chest pain with exertion [see ograph shows an elevated hemidiaphragm. At one time, diaphrag- Figure 1]. Patients with left-side paralysis may experience GI com- matic paralysis was generally considered to be a benign condition, plaints resulting from compression of the stomach [see Figure 2]. but it is now clear that many patients experience various pul- In addition, patients may suffer from recurrent pneumonia, bron- monary, cardiac, and gastrointestinal symptoms. The symptoms chitis, or cardiac arrhythmias. reported are typically nonspecific, and the correct diagnosis is Bilateral diaphragmatic paralysis, on the other hand, is poorly often difficult to make. tolerated. Patients with this condition depend more on their acces- It is helpful to remember that the clinical manifestations of sory muscles of respiration, avoid the supine position, and are diaphragmatic paralysis are usually explained by the pathophysiol- more prone to chronic respiratory failure.5 ogy. Interruption of the phrenic nerve anywhere between the neck In children, diaphragmatic paralysis may cause severe respirato- and the diaphragm results in paralysis of the ipsilateral hemidi- ry distress. Compared with adults, children have weaker inter- aphragm [see Discussion, Diaphragmatic Anatomy, below]. costal muscles, a more compliant chest wall, and a more mobile Because the diaphragm is a continuous muscular sheet, one might mediastinum. Accordingly, children must depend on their suppose that paralysis of one side would adversely affect the other. diaphragms to achieve adequate tidal volumes. Unilateral Actually, the two sides of the diaphragm function independently: diaphragmatic paralysis in a child usually necessitates mechanical tension from one side is not distributed to the other across the ventilation; bilateral paralysis is often fatal without prompt venti- central tendon.1 Bilateral diaphragmatic paralysis is rarely encoun- latory support. tered by the thoracic surgeon. When it does occur, it is usually a manifestation of neuromuscular or systemic disease. Common Causes of Diaphragmatic Paralysis The functional effects of hemidiaphragmatic paralysis are simi- As noted (see above), bilateral diaphragmatic paralysis is usual- lar to but less striking than those of bilateral paralysis [see ly a manifestation of a systemic disease, such as a neuromuscular Discussion, Normal Diaphragmatic Function, below].2 An elevat- junction disorder, an immunologic phenomenon, or a myopathy. ed hemidiaphragm compresses the hemithorax and results in a Because thoracic surgeons rarely treat these conditions, the ensu- restrictive pattern of lung disease. In the seated position, the patient’s vital capacity and total lung capacity decrease by approx- imately 20%; in the supine position, vital capacity decreases by nearly 40%.3 Ventilation and perfusion of the lower lobe are also reduced on the affected side. Mismatching may widen the alveo- lar-arterial oxygen difference and produce mild hypoxemia.4 Generally, adults with healthy lungs tolerate these changes well; however, patients who are obese or have underlying lung disease are more likely to be symptomatic. Diaphragmatic paralysis is frequently described in the literature in conjunction with eventration of the diaphragm. Eventration is a condition in which all or a portion of one hemidiaphragm is per- manently elevated while retaining its continuity and its normal attachments to the costal margins. Although eventration and uni- lateral paralysis are technically different, they often give rise to the same physiologic disturbances and radiographic findings. Clinical Evaluation HISTORY Figure 1 Shown is a postoperative radiograph from a 55-year- In adults, the clinical presentation of uni- old woman who underwent left upper lobectomy. Because the lateral paralysis of the diaphragm is highly tumor was directly adherent to the phrenic nerve, a 2 cm portion variable. Right and left hemidiaphragmatic of the left phrenic nerve was resected along with the tumor. paralysis seem to occur with equal frequency Recovery was uneventful, and the only late symptom was mild and usually cause little or no respiratory dyspnea with exertion.
  2. 2. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 2 Evaluation of Elevated Hemidiaphragm Patient presents with elevated hemidiaphragm on chest x-ray Obtain clinical history: • Previous operations (iatrogenic phrenic nerve injury) • Malignancy involving phrenic nerve • Respiratory symptoms (exertional dyspnea, cough, difficulty in sleeping) • GI symptoms (dysphagia, dyspepsia) • Cardiac symptoms (dysrhythmia) Perform physical examination: • Auscultation for decreased breath sounds • Percussion to assess diaphragmatic excursion Order investigative studies: • Inspiratory and expiratory chest x-ray (to confirm elevated hemidiaphragm) • Fluoroscopy and sniff test (to distinguish diaphragmatic paralysis from weakness) • Cervical phrenic nerve stimulation (to clarify diagnosis in patients on mechanical ventilation when sniff test is inconclusive—rarely necessary) Patient is asymptomatic or Patient has significant symptoms (e.g., dyspnea, has only mild symptoms recurrent pneumonia, chronic bronchitis, chest pain, poor exercise tolerance, cardiac dysrhythmia, or Treat conservatively: functional gastric disorder) • Physical therapy • Pulmonary rehabilitation Order further tests as required: • Weight loss • Pulmonary (pulmonary function tests) • Cardiac (ECG, echocardiography) • GI (gastric motility study) Treat surgically with diaphragmatic plication (open or thoracoscopic).
  3. 3. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 3 inite connection between the two has not been established. The outcome of phrenic nerve injury incurred during cardiac surgery has been well studied. In many cases, the injured phrenic nerves recover; typical recovery times for diaphragmatic function range from 6 months to 2 years.6,8 In 20% of cases, however, the injury is permanent [see Figure 3]. Although morbidity is usually minimal, bilateral diaphragmatic paralysis after cardiac surgery has occasionally resulted in death. It should be kept in mind that diaphragmatic paralysis after cardiac surgery is a more serious problem in children than in adults. In pediatric patients, phrenic nerve injury usually results in respiratory distress, which may pre- vent weaning from mechanical ventilation.9 In current usage, the term iatrogenic phrenic nerve injury refers to either (1) unintentional injury to the nerve during an operation or (2) intentional resection of the nerve to permit complete exci- sion of a chest neoplasm. In the past, however, phrenic nerve injury was sometimes deliberately induced to elevate or disable a hemidiaphragm for therapeutic purposes, either permanently or temporarily. Therapeutic phrenic nerve paralysis was originally achieved by crushing the nerve at the level of the diaphragm with Figure 2 Shown is a postoperative radiograph of a 70-year-old a surgical clamp; subsequently, temporary paralysis was achieved man who underwent left upper lobectomy for removal of a periph- by exposing the phrenic nerve in the neck and infiltrating the area eral 3 cm lesion. The phrenic nerve was injured with the electro- around it with local anesthetics. This technique was employed in cautery during mediastinal lymph node dissection. The radi- the treatment of pulmonary tuberculosis and was occasionally ograph shows permanent elevation of the left hemidiaphragm performed to elevate a hemidiaphragm and help obliterate a diffi- with gastric bloating 3 years after operation. The patient is neither dyspneic nor dyspeptic and does not require surgical intervention. cult pleural space problem. It must be emphasized that in current practice, therapeutic phrenic nerve paralysis is of historic interest only. It is never necessary, and it is no longer considered appro- ing discussion focuses on conditions associated with isolated priate or beneficial. diaphragmatic paralysis [see Table 1].The two most common caus- es of unilateral diaphragmatic paralysis are (1) iatrogenic injury Malignancy involving phrenic nerve Neoplastic involve- after a cardiothoracic or cervical procedure and (2) malignancy. ment of the phrenic nerve accounts for one third of cases of diaphragmatic paralysis.10 Bronchogenic carcinomas are the Injury to phrenic nerve Common mechanisms of phrenic lesions that most commonly affect the phrenic nerve, and paraly- nerve injury during cardiac procedures include stretching, crush- sis is usually secondary to mediastinal lymph node involvement or ing, transection, and hypothermia. During the mid-1980s, topical direct mediastinal invasion by central tumors. Other mediastinal ice slush was frequently employed in cardiopulmonary bypass pro- tumors that may affect the phrenic nerve include thymomas, lym- cedures, and this practice dramatically increased the incidence of phomas, and germ cell tumors. It is reassuring to note that in phrenic nerve injury. After cooling jackets replaced topical ice slush patients with unilateral diaphragmatic paralysis of no clear origin, in this setting, the incidence of elevated hemidiaphragms fell from malignancy turns out to be the cause in fewer than 5% of cases. 23% to 2%.6,7 It has been suggested that harvesting the internal Although patients with unexplained diaphragmatic paralysis are mammary artery may contribute to phrenic nerve injury, but a def- unlikely to have an occult malignancy, they are also unlikely to recover their diaphragmatic function.10 PHYSICAL EXAMINATION Table 1—Causes of Isolated Diaphragmatic Patients with diaphragmatic paralysis may be asymptomatic or Paralysis may present with some of the nonspecific clinical findings men- tioned (see above). Physical examination usually reveals decreased Idiopathic paralysis Phrenic neuropathy breath sounds on the affected side, a mediastinal shift during inspi- Phrenic nerve injury ration, or a scaphoid abdomen. Percussion may demonstrate an Iatrogenic elevated hemidiaphragm with decreased excursion on inspiration. Malignancy (invasion or compression) Trauma Therapeutic (tuberculosis) Investigative Studies Mononeuritis In the majority of cases, an asympto- Viral infection (Guillain-Barré syndrome) matic person is referred to the surgeon Vasculitis because a chest radiograph demonstrates Diabetes an elevated hemidiaphragm. It is impor- Connective tissue disease Anterior horn cell lesions tant to remember that there is a broad dif- Herpes zoster ferential diagnosis for an elevated hemidi- Poliomyelitis aphragm and that diaphragmatic paralysis Amyotrophic lateral sclerosis is relatively rare [see Table 2]. Workup usually begins with inspiratory and expiratory chest
  4. 4. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 4 a b c Figure 3 Shown are three chest radi- ographs of a 25-year-old man with residual anterior mediastinal mass after treatment for germ cell tumor. (a) Preoperative view shows normal diaphragmatic positioning bilaterally. (b) Immediate postoperative view demonstrates an elevated right hemidi- aphragm, attributed to stretch injury and electrothermal injury caused by dissection of mass from the vicinity of the phrenic nerve at the right hilum. (c) Late view, 3 months after operation, reveals gradual restoration of normal diaphragm positioning. Patient is asymptomatic. radiographs. However, fluoroscopic examination is the most prac- sniff test, a definitive diagnosis can be made by employing cervi- tical method of assessing the movement of the diaphragm. The cal phrenic nerve stimulation in conjunction with electromyo- excursion of the domes of the diaphragm averages 3 to 5 cm and graphic measurement of phrenic nerve latency.13 This final test is may range from 2 to 10 cm.11 The examination is typically per- rarely necessary. formed with the patient standing, but it is more sensitive when the patient is supine because the effect of gravity is removed. In a patient with unilateral paralysis, the paralyzed hemidiaphragm Management moves upward with rapid inspiration and downward with expira- CONSERVATIVE VERSUS SURGICAL tion. This paradoxical motion passively follows changes in TREATMENT intrapleural and intra-abdominal pressure. The so-called sniff test is then performed to confirm that the Treatment is individualized and depends abnormal diaphragm excursion is the result of paralysis rather on the degree to which the patient is inca- than of weakness. During this test, the patient inhales forcefully pacitated. Most healthy adults with isolated and rapidly through the nose with the mouth closed. A sharp and diaphragmatic paralysis are asymptomatic or suffer only from mild brief downward motion in both hemidiaphragms is the normal exertional dyspnea. The vast majority of these patients do not response when paralysis is absent. If an entire hemidiaphragm require surgical treatment and are best treated conservatively (e.g., exhibits a paradoxical upward motion greater than 2 cm, howev- with physical therapy, pulmonary rehabilitation, and counseling on er, diaphragmatic paralysis is likely.12 The diagnosis of diaphrag- weight loss, if necessary). Just as many patients with normal lung matic paralysis may be difficult to make in patients with severe function can tolerate major pulmonary resections, most patients chronic obstructive pulmonary disease, in whom normal hemidi- who are otherwise fit can tolerate unilateral diaphragmatic paraly- aphragms move very little. The sniff test may also be inconclusive sis without the need for surgical intervention. in weak, debilitated patients, who often are incapable of produc- Operative management may, however, be indicated for children ing a forceful sniff. In patients who are undergoing mechanical and for adults who have significant symptoms (e.g., dyspnea, ventilation and in whom the diagnosis remains in doubt after a recurrent pneumonia, chronic bronchitis, chest pain, poor exercise
  5. 5. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 5 tolerance, cardiac arrhythmias, or functional disorders of the There was a small improvement in tidal volume after bilateral pli- stomach).14 The classic treatment is diaphragmatic plication, cation, but this was probably attributable to improved rib cage which may be performed either via a thoracotomy or thoraco- efficiency secondary to diaphragmatic fixation. scopically. Plication of the diaphragm was first performed in 1947 These findings may explain why bilateral plication has been to treat congenital eventration of the diaphragm, and the basic more beneficial for adults than it has been for children,20 who principles of the procedure have changed little since then.15 depend more on the diaphragmatic contribution to respiration. In infants, the small improvement in rib cage efficiency may not PLICATION OF DIAPHRAGM be large enough to allow them to be weaned from mechanical ven- tilation. In children with hemidiaphragmatic paralysis, however, Open plication is essential for improving diaphragmatic efficiency and A standard diaphragmatic plication is performed through a preventing complications associated with long-term mechanical posterolateral thoracotomy in the eighth intercostal space. The ventilation.20 lung and the mediastinum are examined to exclude any unsus- pected pathologic conditions. The uncut diaphragm is plicated Thoracoscopic with four to six parallel rows of heavy nonabsorbable sutures.The In 1996, a thoracoscopy-assisted approach to diaphragmatic stitches are placed in an anterolateral-to-posterolateral direction, plication was first described. The goal was to achieve an equiva- and each row takes several bites of the diaphragm to form pleats. lent degree of plication by less invasive means.21 Three patients The sutures are tied only after all the rows have been placed. were treated in this fashion.The procedure made use of a double- When all of the sutures are placed and tied, the diaphragm should lumen endotracheal tube, two thoracoscopic ports, and a 5 cm be tight, and much of the plicated tissue should lie within the cen- minithoracotomy. The diaphragm was invaginated and stitched tral tendon. with two rows of continuous sutures. The results were excellent, Open diaphragmatic plication is an effective procedure for and the average hospital stay was 8 days. All three patients showed treating diaphragmatic paralysis. In a study of 17 patients who significant improvements in FVC and FEV1: FVC improved by underwent plication for exertional dyspnea,16 no major complica- 9% to 22%, and FEV1 improved by 11% to 14%.These improve- tions were reported during a mean hospital stay of 11 days. At 6 ments were maintained for a minimum of 17 months. months’ follow-up, patients exhibited significant improvements Since this first description, several reports of successful with respect to dyspnea score, forced vital capacity (FVC), total diaphragmatic plication with a purely thoracoscopic approach lung capacity (TLC), functional residual capacity (FRC), and (using three or four ports) have been published.14,22 These case arterial oxygenation. Furthermore, the subjective and objective reports documented symptomatic improvement and reduced improvements were maintained for at least 5 years. In a subse- length of stay (4 days); however, they did not document significant quent series from the United Kingdom, similar results were improvements in FVC or FEV1.Thoracoscopic diaphragmatic pli- observed at a mean follow-up of 10 years: 14 of 15 patients were cation appears to be the surgical method of the future, but larger satisfied with their plication and had returned to work.17 In addi- series with longer follow-up periods are needed. The main con- tion, FVC, forced expiratory volume in 1 second (FEV1), FRC, traindication to thoracoscopic plication is extensive pleural adhe- and TLC improved by 12%, 15%, 26%, and 13%, respectively. sions from inflammatory reactions or previous operations. Research has also been performed on changes in respiratory SURGICAL PROPHYLAXIS AFTER PHRENIC NERVE INJURY mechanics after diaphragmatic plication. In 1980, one group noted that plication was more successful for hemiparalysis than for bilateral diaphragmatic paralysis.18 These clinical results sub- Phrenic Nerve Repair versus Prophylactic Plication sequently led another group to hypothesize that normal function- An area of investigation that, to date, has not been sufficiently ing of the contralateral hemidiaphragm might be required to explored is the potential role of prophylactic procedures in cases derive significant benefit from diaphragmatic plication.19 These where one is confident that a phrenic nerve has been injured dur- investigators demonstrated that plication for unilateral paralysis ing an operation and wishes to reverse or at least mitigate the improved the strength of the normal contralateral hemidi- effect of the injury. aphragm, so that the contralateral hemidiaphragm functioned as a If the injury resulted from sharp dissection, so that the entire better pressure generator and thus made a greater contribution to nerve is present but divided, one may elect to repair the nerve. On breathing. However, they found that bilateral plication for bilater- occasion, we have invited colleagues from plastic surgery to per- al paralysis did not yield significant improvements with respect to form microsurgical anastomoses between the cut ends of the sev- diaphragmatic function, lung compliance, or work of breathing. ered nerves, but we have never attempted a formal analysis of this practice. Such a repair would not, of course, be feasible in a case where the phrenic nerve was resected in the course of excision of an attached invasive tumor. Table 2—Differential Diagnosis of Elevated If the nerve was resected or was injured beyond hope of recov- Hemidiaphragm on Chest Radiograph ery, one may reasonably consider plicating the diaphragm during the same operation so as to minimize the impact of the diaphrag- Volume loss (atelectasis, lobar collapse, hypoplasia) Splinting matic paralysis without having to perform another operation later. Pleural disease (subpulmonic effusion, mass) This strategy has not yet been studied in the surgical literature, but Diaphragmatic hernia it should be kept in mind for the rare instances of phrenic nerve Eventration resection or injury during pulmonary or mediastinal resection. Phrenic nerve paralysis Abdominal disease (dilated viscera, abscess) PACING OF DIAPHRAGM Single-lung transplantation for pulmonary fibrosis Although pacing of the diaphragm requires an intact phrenic nerve and thus is not useful in cases of classic diaphragmatic
  6. 6. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 6 paralysis, it is an established mode of ventilatory support with requires normal lungs with the ability to oxygenate and ventilate which the thoracic surgeon should be familiar.The two main indi- in response to diaphragmatic movement; severe restrictive lung dis- cations for diaphragmatic pacing are central alveolar hypoventila- ease and major chest wall deformities are contraindications tion and high cervical spinal cord injury; less common indications to pacing. In addition, it is crucial that the patient be cooperative and are intractable hiccups and end-stage chronic obstructive pul- motivated and have adequate support from nursing staff and family. monary disease. Central alveolar hypoventilation is a form of sleep Phrenic nerve pacing involves the use of an extracorporeal gen- apnea resulting from failure of the respiratory drive itself rather erator with an antenna that transmits radiofrequency signals to a than from an anatomic obstruction. It is also known as Ondine’s subcutaneous radio receiver; the receiver then translates the curse (from the German myth about the water nymph Ondine, radiofrequency signal into direct current, which is delivered who, finding that her mortal husband had been unfaithful, placed through electrodes to the phrenic nerves. The electrodes are a fatal curse on him so that he would only breathe while awake).23 placed on the phrenic nerves via bilateral anterior thoracotomies The underlying cause is impaired sensitivity of the brain’s respira- or neck incisions. Several different commercial pacing systems are tory control center to alterations in oxygenation.The clinical result available, but they all work according to the same basic concept. is persistent hypoventilation with sleep apnea and the develop- Phrenic nerve pacing remains a relatively rare procedure. The ment of pulmonary hypertension. largest series published to date included 165 patients, of whom The use of electricity to induce diaphragmatic contraction was 27% were paced on a full-time basis and 63% on a part-time first suggested by Hufeland in 1783.24 Besides an intact phrenic basis.25 Phrenic nerve pacing met the ventilatory requirements of nerve and a functioning diaphragm, diaphragmatic pacing also 47% of the patients and was partially successful in 36%. Discussion Diaphragmatic Anatomy The left and right phrenic nerves arise from the C3–C5 nerve For the purposes of discussion, the diaphragm may usefully be roots and travel a distance of 30 to 40 cm between their cervical divided into left and right hemidiaphragms. In anatomic terms, origin and their termination on the surface of the diaphragm. A the diaphragm is a dome-shaped muscle that can be described as firm understanding of the anatomy of the phrenic nerves is cru- having both muscular and tendinous components. The muscular cial for the thoracic surgeon because iatrogenic injury during portion of the diaphragm is divided into three parts, each of which operation is a leading cause of diaphragmatic paralysis. Both originates from one of the three structural elements forming the nerves originate on the middle scalene muscle and cross to the lower thoracic aperture: the pars lumbalis diaphragmatis (origi- anterior scalene muscle, where they descend within an investment nating from the lumbar spine), the pars costalis diaphragmatis of fascia. At the base of the neck, the left phrenic nerve crosses the (from the ribs), and the pars sternalis diaphragmatis (from the thoracic duct, descending into the thorax on the anterior surface sternum). The pars lumbalis is the most powerful region of the of the left subclavian artery. It then travels between the left com- diaphragm.26 All three parts insert into a central aponeurosis mon carotid and subclavian arteries, crosses in front of the vagus known as the central tendon. This tendon has a cloverleaf shape, nerve, and passes lateral to the aortic arch, where it descends with one leaf directed anteriorly and two leaves directed laterally along the pericardium to a point just above the diaphragm. At the (one into each hemithorax). thoracic inlet, the right phrenic nerve is located behind the The diaphragm possesses three major apertures, which allow innominate vein and usually crosses in front of the internal mam- passage of the inferior vena cava, the esophagus, and the aorta. mary artery. It descends to the right of the innominate vein and The caval orifice is located in the right portion of the central ten- the superior vena cava before reaching the pericardium, anterior don, typically at the level of T8. Diaphragmatic contraction to the lung. Finally, the right phrenic nerve descends along the stretches this orifice and may facilitate the return of blood to the inferior vena cava toward the diaphragm. Both phrenic nerves heart during inspiration. The right phrenic nerve and some lym- branch just proximal to the diaphragm, and small terminal phatic vessels also pass through this orifice.The esophageal hiatus branches innervate the muscle. is located behind the central tendon at the level of T10.This aper- ture, unlike the other two, is ventrally framed by muscle.The aor- tic opening is anterior to T12, between the crura and behind the Normal Diaphragmatic Function median arcuate ligament. The aortic opening also allows passage The diaphragm is the most important respiratory muscle. of the azygos vein, the thoracic duct, and lymphatic channels as During inspiration, the diaphragm contracts and moves caudally they descend from the thorax into the abdomen. in a pistonlike fashion.This motion forces the abdominal contents The arterial supply to the cranial surface of the diaphragm down and forward, increasing the vertical dimension of the chest consists of the pericardiophrenic, musculophrenic, and superior cavity. In addition, the ribs lift the lateral aspect of the diaphragm phrenic arteries. The posterior aspect of the diaphragm is sup- during inspiration, causing the transverse diameter of the thorax plied by small direct branches from the aorta.The caudal surface to increase. As the diaphragm contracts, pleural pressure decreas- of the diaphragm is supplied by the inferior phrenic arteries, es, facilitating lung inflation. Normal diaphragmatic function which arise from the aorta or the celiac trunk; these arteries are accounts for 75% of air movement during normal respiration and much larger than the superior phrenic arteries. Occasionally, the is responsible for 60% of minute volume in the supine position. right inferior phrenic artery originates from the right renal Diaphragmatic excursion averages about 1 cm during normal artery.27 The venous drainage from the diaphragm mirrors the tidal breathing, but it can increase to 10 cm during forced inspi- arterial supply. ration and expiration.28
  7. 7. © 2005 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice 4 THORAX 6 PARALYZED DIAPHRAGM — 7 References 1. Whitelaw WA: Shape and size of the human Unexplained diaphragmatic paralysis: a harbinger in dogs with unilateral and bilateral phrenic nerve diaphragm in-vivo. J Appl Physiol 62:180, 1987 of malignant disease? J Thorac Cardiovasc Surg paralyses. Chest 107:798, 1995 2. Gibson GJ: Diaphragmatic paresis: pathophysiol- 84:861, 1982 20. Simansky DA, Paley M, Refaely Y, et al: Dia- ogy, clinical features, and investigation. Thorax 11. Gierada DS, Slone RM, Fleishman MJ: Imaging phragm plication following phrenic nerve injury: 44:960, 1989 evaluation of the diaphragm. Chest Surg Clin N a comparison of paediatric and adult patients. 3. Clague HW, Hall DR: Effect of posture on lung Am 8:237, 1998 Thorax 57:613, 2002 volume airway closure and gas exchange in hemidi- 12. Alexander C: Diaphragm movements and the 21. Mouroux J, Padovani B, Poirier NC, et al: Tech- aphragmatic paralysis. Thorax 34:523, 1979 diagnosis of diaphragmatic paralysis. Clin Radiol nique for the repair of diaphragmatic eventration. 4. Easton PA, Fleetham JA, de la Rocha A, et al: 17:79, 1966 Ann Thorac Surg 62:905, 1996 Respiratory function after paralysis of the right 13. Stochina M, Ferber I, Wolf E: Evaluation of the 22. Sloane GT, Montany PF: Thoracoscopic dia- hemidiaphragm. Am Rev Respir Dis 127:125, 1983 phrenic nerve in patients with neuromuscular dis- phragmatic plication. Surg Laparosc Endosc 8: 5. Rochester DF: The diaphragm: contractile prop- orders. Int J Rehabil Res 6:455, 1983 319, 1998 erties and fatigue. J Clin Invest 75:1397, 1985 14. Suzumura Y, Terada Y, Sonobe M, et al: A case of 23. Goldblatt D: Historical note: Ondine’s curse. 6. Curtis JJ, Weerachai N, Walls J, et al: Elevated unilateral diaphragmatic eventration treated by Semin Neurol 15:218, 1995 hemidiaphragm after cardiac operations: inci- plication with thoracoscopic surgery. Chest 112: 24. Hufeland CW: Usum uis electriciae in asphyxia dence, prognosis and relationship to the use of 530, 1997 experimentis illustratum. Dissertatio Inauguralis topical ice slush. Ann Thorac Surg 48:764, 1989 15. Bisgard JD: Congenital eventration of the dia- Medica, Göttingen, Germany, 1783 7. Wheeler WE, Rubis LJ, Jones CW, et al: Etiology phragm. J Thorac Surg 16:489, 1947 25. Glenn WWL, Bouillette RT, Dentz B, et al: and prevention of topical cardiac hypothermia- 16. Graham FT, Kaplan D, Evans CC, et al: Dia- Fundamental consideration in pacing of the dia- induced phrenic nerve injury and left lower lobe phragmatic plication for unilateral diaphragmatic phragm for chronic ventilatory insufficiency: a atelectasis during cardiac surgery. Chest 88:680, paralysis: a 10-year experience. Ann Thorac Surg multi-institutional study: part II. Pacing Clin 1985 49:248, 1990 Electrophysiol 11:2121, 1988 8. Markand ON, Moorthy SS, Mahomed Y, et al: 17. Higgs SM, Hussain A, Jackson M, et al: Long 26. Fell SC: Surgical anatomy of the diaphragm and Postoperative phrenic nerve palsy in patients with term results of diaphragmatic plication for unilat- the phrenic nerve. Chest Surg Clin N Am 8:281, open-heart surgery. Ann Thorac Surg 39:68, eral diaphragm paralysis. Eur J Cardiothorac Surg 1998 1985 21:294, 2002 27. Schumpelick V, Steinau G, Schluper I, et al: 9. De Leeuw M, Williams JM, Freedom RM, et al: 18. Schonfeld T, O’Neal MH, Platzker ACG, et al: Surgical embryology and anatomy of the Impact of diaphragmatic paralysis after cardio- Function of the diaphragm before and after plica- diaphragm with surgical applications. Surg Clin thoracic surgery in children. J Thorac Cardiovasc tion. Thorax 35:631, 1980 North Am 80:213, 2000 Surg 118:510, 1999 19. Takeda S, Nakahara K, Fujii Y, et al: Effects of 28. West JB: Respiratory Physiology: The Essentials, 10. Piehler JM, Pairolero PC, Gracey DR, et al: diaphragmatic plication on respiratory mechanics 6th ed. Williams and Wilkins, Baltimore, 2000

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