Anterior Diaphragmatic Plication in Mediastinal Surgery: The “Reefing the Mainsail” Technique

Diaphragmatic plication is usually obtained by suturing the entire dome, which can be laborious when an anterior approach is used. The same result can be obtained by anchoring the redundant diaphragm to the anterior costal arch maneuver, which resembles the action of reefing the mainsail on the boom of a sailboat. Radiologic results have been analyzed from a series of 10 consecutive patients who underwent mediastinal surgery with phrenic nerve section. One week after surgery, no patient had an eventrated diaphragm on lateral chest roentgenogram. No lower lobe atelectasis was recorded in the series until discharge. This technique represents an alternative to classic diaphragmatic plication with three main advantages: (1) it does not require suturing of the posterior part of the dome, which can be difficult to reach when an anterior approach (sternotomy or hemi-clamshell) is used; (2) the presence of three sequential steps, which progressively increases diaphragmatic stretching and permits adjusting the tension of the dome; and (3) the possibility of standard plication is not precluded. Diaphragmatic plication is usually obtained by suturing the entire dome, which can be laborious when an anterior approach is used. The same result can be obtained by anchoring the redundant diaphragm to the anterior costal arch maneuver, which resembles the action of reefing the mainsail on the boom of a sailboat. Radiologic results have been analyzed from a series of 10 consecutive patients who underwent mediastinal surgery with phrenic nerve section. One week after surgery, no patient had an eventrated diaphragm on lateral chest roentgenogram. No lower lobe atelectasis was recorded in the series until discharge. This technique represents an alternative to classic diaphragmatic plication with three main advantages: (1) it does not require suturing of the posterior part of the dome, which can be difficult to reach when an anterior approach (sternotomy or hemi-clamshell) is used; (2) the presence of three sequential steps, which progressively increases diaphragmatic stretching and permits adjusting the tension of the dome; and (3) the possibility of standard plication is not precluded. Extended mediastinal surgery may require a section of the phrenic nerve to obtain free resection margins. Immediate consequences of such a maneuver are loss of function and eventration of the diaphragm. In the postoperative period, eventration may predispose to lower lobe atelectasis, pleural fluid collection, and contribution to the occurrence of postoperative respiratory failure. Prevention of diaphragmatic eventration may be obtained by plicating the diaphragm before chest closure. Several different techniques for diaphragmatic plication are available [1Mouroux J. Padovani B. Poirier N.C. et al.Technique for the repair of diaphragmatic eventration.Ann Thorac Surg. 1996; 62: 905-907Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar, 2McNamara J.J. Paulson D.L. Urschel H.C. Razzuk M.A. Eventration of the diaphragm.Surgery. 1968; 64: 1013-1021PubMed Google Scholar, 3Chin E.F. Lynn R.B. Surgery of the eventration of the diaphragm.J Thorac Surg. 1956; 32: 6-14PubMed Google Scholar] based on the common principle of lowering the entire diaphragmatic dome by suturing the redundant part from the posterior costo-phrenic angle to the cardio-phrenic angle [4Mouroux J. Venissac N. Leo F. Pop D. Alifano M. Plication of the diaphragm In: Pearson's thoracic and esophageal surgery, 2nd ed.Philadelphia: Churchill & Livingstone. 2008; : 1431-1444Google Scholar]. Access to the posterior part of the diaphragm may be difficult using an anterior approach (sternotomy or hemi-clamshell), which is standard practice in mediastinal tumors. The presented technique, easily performed through any anterior approach, offers an alternative option based on the idea that pulling the redundant diaphragm on a rigid structure (the rib) may obtain the same effect on the diaphragm shape. The entire maneuver resembles the action of reefing the mainsail on the boom of a sailboat. Plication of the diaphragm is progressively obtained by three sequential steps, which can be modulated to obtain the desired tension. The plication is performed by the use of two or three stitches, which first create the diaphragmatic fold, then fix it to the anterior diaphragm, and finally pull the plicated dome against the anterolateral arch of the sixth rib. The two elements that influence the final tension of the diaphragm are the height of the fold and the distance between the first suture line and the costal arch. The redundant diaphragm is elevated by two forceps placed approximately 10 to 15 cm far from the sixth anterior costal arch. After accurate palpation to exclude the presence of abdominal viscera, two Satinsky clamps are placed along the desired suture line creating the diaphragmatic fold. Two or three monofilament polyglyconate absorbable U stitches (Maxon MT20, 48 mm ½-blunt taper needle, 90 cm length) are passed at the base of the fold, keeping a distance of 6 cm to 8 cm among them, and knotted on the posterior side, without cutting the needle (Fig 1). The fold is fixed passing each stitch through the apex of the fold and then through the anterior dome of the diaphragm, maintaining a suture line parallel to the base of the fold (Fig 2). The distance between the two suture lines may vary according to the amount of the redundant diaphragm. Finally, stitches are knotted, maintaining needles on the threads (Fig 3).Fig 3Stitches are knotted and the fold is blocked anteriorly, maintaining needles on the threads. Then each stitch is passed around the anterolateral portion of the sixth rib (arrow).View Large Image Figure ViewerDownload (PPT) Each stitch is passed around the anterior portion of the sixth rib (Fig 3, arrow), maintaining a distance of 4-cm to 6-cm between them. Finally, the plicated diaphragm is pulled against the costal arch by knotting all stitches (Fig 4). At the end of the procedure, two 32-French pleural drains are placed, one of which is placed in the costophrenic angle. This technique was developed in 2004 at the Division of Thoracic Surgery of the National Cancer Institute of Milan and used as standard technique of plication since then. Radiologic results have been analyzed from a series of 10 consecutive patients who underwent mediastinal surgery with phrenic nerve section and without the need of anatomical lung resection. The level of both hemi-diaphragms was compared preoperatively and 7 days after surgery (postoperative day 7) by the use of a digital chest roentgenogram viewing system according to the Christensen method [5Christensen P. Eventration of the diaphragm.Thorax. 1959; 14: 311-319Crossref PubMed Scopus (22) Google Scholar]. On postoperative day 7, no patient had an eventrated diaphragm (defined as an elevation of 3 cm or more as compared with the contralateral) on lateral chest roentgenogram. No lower lobe atelectasis was recorded in the series until discharge. In one case, left pleural effusion developed 2 weeks after discharge and required drainage. One month after surgery, the effusion disappeared and the hemi-diaphragm position was normal. No eventration was recorded during follow-up. As in the whole domain of functional surgery, the balance between the potential harm of any additional procedure and the benefit of preventing eventration is crucial. In mediastinal surgery, our formal indications for diaphragm plication are: (1) preoperative diagnosis of eventration and (2) the intraoperative sacrifice of the phrenic nerve associated with extended dissection along the contralateral phrenic nerve (with the consequential risk of temporary bilateral palsy). In case of pure unilateral phrenic section, our preference is still to plicate the diaphragm, but the benefit of such a preventive maneuver remains questionable, as many patients would be able to cope with a paralyzed hemi-diaphragm without relevant clinical symptoms. In our experience, this technique showed three main advantages: (1) it does not require suturing of the posterior part of the dome, which can be difficult to reach when an anterior approach is used; (2) the presence of three sequential steps, which progressively increase diaphragmatic stretching permits easily obtaining the desired tension; and (3) the possibility of standard plication is not precluded. The use of absorbable sutures for diaphragmatic plication may be debatable, given the theoretical risk of eventration after stitch reabsorption. We routinely used polyglyconate sutures for the last 16 years [6Yang X.N. Pastorino U. Are absorbable sutures inadequate to close the sternum?.J Thorac Cardiovasc Surg. 2006; 132: 1503Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar] due to its mechanical properties, such as elasticity, high tensile strength, and minimal tissue reaction. This was also used in a series of more than 50 direct diaphragmatic repairs, in which no case of suture disrupture has been recorded. Our speculative explanation is that that the long time to reabsorption (ie, well beyond 3 months) allows safe long-term tissue fixation. In conclusion, this technique may represent a useful option when diaphragm plication is needed and the surgical approach does not allow access to the entire dome. Even if clinical outcome of patients from the series was excellent, further studies are required to assess long-term radiologic and functional results.