Minimally invasive pediatric cardiac surgery

We quantitatively studied the role of periosteum and bone marrow-endosteum during lengthening in 18 growing rabbits, comparing four surgical procedures: 1) periosteum and bone marrow preservation, 2) periosteum preservation, bone marrow destruction, 3) periosteum destruction, bone marrow preservation, 4) periosteum and bone marrow destruction. An external fixator was set on one femur, the other serving as a control. Distraction began on day 5 and stopped on day 25 (0.25 mm/12 hours). On day 30, femora were harvested with a layer of muscle. Area, bone mineral content and density were measured by dual-energy x-ray absorptiometry. Procedure 2 showed the highest increase in bone mineral content around the elongated callus (127%) compared to procedures: 1 (81%), 3 (25%) and 4 (-8%, i.e., resorption of bone ends). A statistically significant effect on bone formation was observed when preserving (vs. destroying): 1) periosteum, 2) bone marrow (effect observed only around the distraction gap), 3) periosteum and bone marrow in combination. Periosteum alone forms a larger callus, with more mineral content than bone marrow alone, and destruction of both results in the absence of bone formation around the distraction area. Careful preservation of periosteum is essential to bone healing. Formation of bone with a large mineral content does not require bone marrow preservation, but there is an interaction effect on healing between bone marrow and periosteum.     

Minimally invasive cardiac surgery: current status and perspective

This study investigated the features of calf deep vein thrombosis (DVT) as a pulmonary embolic source. Fifty-eight lower limbs in 29 patients who were suspected of having DVT distal to the popliteal vein were screened by ultrasonography. Then, ascending venography was performed to confirm the diagnosis. Pulmonary embolism (PE) was diagnosed in suspected patients by use of pulmonary perfusion scanning or pulmonary angiography. Venography revealed calf DVT in 33 limbs in 28 patients. Of 28 patients, six had symptomatic PE. Thrombosis was found in the muscle veins in 18 limbs, the trunk veins in 11, and both veins in four. Isolated single vein thrombosis was found in the soleal vein in 14 limbs (42%), the posterior tibial vein in eight, the peroneal vein in two, and the gastrocnemius vein in two. The overall percentage of soleal vein thrombi was 61%. All six patients with symptomatic PE had isolated soleal vein thromboses. Calf DVT was a pulmonary embolic source when isolated thrombosis of the large soleal vein was more than 7 mm in diameter. Soleal veins were the most frequent and important location of calf DVT, suggesting that these were an occasional embolic source of critical PE.     

Minimally invasive esophageal surgery

OBJECTIVE: This study aimed to assess patient satisfaction and change in functional status after surgery for epiretinal membrane (ERM), rhegmatogenous retinal detachment (RRD), and complex retinal detachment (CRD). This study also aimed to determine whether objective measures of vision are predictive of subjective improvement after surgery. DESIGN: The study design included patient interviews and retrospective chart review. PARTICIPANTS: Participants were those patients who underwent surgery for ERM, RRD, or CRD by one surgeon at the Bascom Palmer Eye Institute between January 1, 1993, and December 31, 1994. INTERVENTION: Patient satisfaction and patients' perceptions of the impact of surgery on their functional status were assessed by telephone interviews conducted by one interviewer at least 6 months after surgery. MAIN OUTCOME MEASURES: Responses to patient satisfaction survey and subjective change in patients' functional status were measured. RESULTS: Of 187 eligible patients, 146 (78.1%) could be contacted and all agreed to participate. Ninety patients (61.6%) reported improved functioning after surgery in 2 or more of the 5 activities investigated. Twenty-one patients (14.4%) reported worse postoperative vision than expected, but only 5 patients (3.4%) thought surgery had not been worthwhile. One hundred forty-three patients (97.9%) reported adequate explanation of surgery and its expected results. Patients with preoperative study eye visual acuity between 20/40 and 20/200 were most likely to improve in two or more activities. Lower preoperative worse eye vision and better final study eye vision were associated with a greater likelihood of satisfaction after surgery. Diagnostic category was not predictive of change in functional status or patient satisfaction. CONCLUSIONS: There is a high rate of patient satisfaction and improved functional status after surgery for ERM, RRD, and CRD, even among patients with good fellow eye vision.     

Minimally invasive knee joint surgery

The treatment of knee joint injuries has seen a marked development. Arthroscopy is standard for diagnostic purposes, for meniscus resection and meniscus refixation. Anterior cruciate ligament reconstruction may be performed mini-invasive by arthroscopic or mini-open technique with comparable result. Drill guide systems and fixation techniques allow for precise and stable graft placement. Posterior cruciate ligament surgery is presently undergoing a similar process of optimisation as ACL surgery has some years ago. The surgical trauma of intraarticular fracture reconstruction was also reduced significantly. Retrograde nailing, percutaneous plating and specific exposures to distal femur and proximal tibia fractures have been established. Percutaneous osteosynthesis controlled by arthroscopy or fluoroscopy is widely used for B-fractures of the tibial plateau. Injectable bone mineral cement adds to reduced trauma of surgical treatment of these fractures. Mini-invasive knee surgery will develop rapidly in the coming years.     

Minimally invasive interventions in heart surgery

Recently a number of minimally invasive surgical techniques have been developed in order to reduce surgical trauma especially to avoid median sternotomy and cardio-pulmonary bypass (CPB). In March 1996 we started successfully a clinical trial with the Port Access technique at our institution for the first time in Europe for the treatment of coronary artery single vessel disease. In addition mitral valve disease, aortic valve disease and ASD were treated successfully with minimally invasive surgical techniques. We developed a new minimally invasive surgical technique (Dresden technique) for the treatment of coronary artery multi vessel disease at our institution. Besides we used several minimally invasive surgical techniques without CPB. Our results indicate that minimally invasive surgical techniques routinely used will decrease the morbidity and time of convalescence after cardiac surgery. These techniques can be applied for a variety of cardiac diseases.     

Minimally invasive surgery for solid tumors

The use of minimally invasive surgery in patients with cancer is slowly evolving. There are a number of reports describing laparoscopy in adults for pancreatic, ovarian, gastric, and colon cancers. In addition, thoracoscopy has been described for lung and esophageal cancers. The role of laparoscopy and thoracoscopy in children with cancer is less clear because a number of pediatric neoplasms are sensitive to adjuvant therapy and surgery is often part of a planned multi-dimensional approach. This article describes a previous reported experience with minimally invasive surgery in children with cancer, current indications for this approach, and general principles which are important regarding the operative technique. In addition, future applications for this technology are suggested.     

Minimally invasive cardiac valve surgery improves patient satisfaction while reducing costs of cardiac valve replacement and repair

OBJECTIVE: This study compares the quality of valve replacement and repair performed through minimally invasive incisions as compared to the standard operation for aortic and mitral valve replacement. SUMMARY BACKGROUND DATA: With the advent of minimally invasive laparoscopic approaches to orthopedic surgery, urology, general surgery, and thoracic surgery, it now is apparent that standard cardiac valve operations can be performed through very small incisions with similar approaches. METHODS: Eighty-four patients underwent minimally invasive aortic (n = 41) and minimally invasive mitral valve repair and replacement (n = 43) between July 1996 and April 1997. Demographics, procedures, operative techniques, and postoperative morbidity and mortality were calculated, and a subset of the first 50 patients was compared to a 50-patient cohort who underwent the same operation through a conventional median sternotomy. Demographics, postoperative morbidity and mortality, patient satisfaction, and charges were compared. RESULTS: Of the 84 patients, there were 2 operative mortalities both in class IV aortic patients from multisystem organ failure. There was no operative mortality in the patients undergoing mitral valve replacement or repair. The operations were carried out with the same accuracy and attention to detail as with the conventional operation. There was minimal postoperative bleeding, cerebral vascular accidents, or other major morbidity. Groin cannulation complications primarily were related to atherosclerotic femoral arteries. A comparison of the minimally invasive to the conventional group, although operative time and ischemia time was higher in minimally invasive group, the requirement for erythrocytes was significantly less, patient satisfaction was significantly greater, and charges were approximately 20% less than those in the conventional group. CONCLUSIONS: Minimally invasive aortic and mitral valve surgery in patients without coronary disease can be done safely and accurately through small incisions. Patient satisfaction is up, return to normality is higher, and requirement for postrehabilitation services is less. In addition, the charges are approximately 20% less. These results serve as a paradigm for the future in terms of valve surgery in the managed care environment.     

Minimally invasive direct coronary artery bypass surgery

Traditional coronary artery bypass surgery involves a median sternotomy and the use of a heart-lung machine to stabilize the heart during suturing. Minimally invasive coronary artery surgery employs small incisions directly over the target vessels and avoids the use of a heart-lung machine, which can cause postoperative complications. The target coronary vessels are stabilized in alternative ways, potentially hazardous manipulation of the ascending aorta is avoided, and the subclavian and axillary arteries provide alternative inflow sources. Other new techniques used in minimally invasive procedures include a coronary artery cannula to avoid intraoperative ischemia and wound irrigation catheters to administer postoperative bupivacaine hydrochloride. Perioperative nurses need to become familiar with these new techniques to be able to plan and implement effective patient care.     

Minimally invasive cardiac surgery in the adult: surgical instruments, equipment, and techniques

To clarify the special instruments and equipment used for minimally invasive cardiac surgery (MICS), we examined the initial experiences with MICS operations with ministernotomy or minithoracotomy at our institution. Fifty adult patients with congenital, valvular, and/or ischemic heart diseases underwent MICS operations, and all surgical procedures were completed without conversion to full sternotomy. The length of the skin incision was about 10 cm or less in all patients. Postoperative recovery was favorable, and the majority of the patients were discharged from the hospital around the end of the second postoperative week. In this series of patients, an oscillating bone saw, lifting type retractor, 2 blade spreader, cannula with a balloon, and right-angled aortic clamp among other items, were very useful for successfully performing various operations with MICS approaches and techniques. The associated results suggest that MICS with ministernotomy or minithoracotomy was feasible using special instruments and equipment and could be encouraged for adult patients with various cardiovascular diseases.     

Minimally invasive valve surgery versus the conventional approach

As a result of reports touting the effectiveness of minimally invasive valve operations, many cardiovascular surgeons and their patients are beginning to believe that smaller incisions are always better. According to its proponents, the minimally invasive approach results in less pain, a faster recovery, and a more satisfactory cosmetic result. Proponents also believe that the operation can be done safely and effectively at a lower cost than traditional surgical approaches. This may not be the case, however, and additional prospective studies must be done before firm conclusions can be drawn. For example, cardiopulmonary bypass, myocardial ischemia, and overall operative times are significantly longer (40% or more) for minimally invasive surgical procedures. Morbidity and mortality rates do not appear to be decreased, the length of hospital stay varies by only 1 or 2 days, and patients do not necessarily report less postoperative pain. When the conventional technique is used, the operation can be performed precisely and expeditiously. Should complications occur, the surgeon will have direct access to the heart. The cost of a conventional procedure should not be much more than that of a minimally invasive procedure, and in some instances it may even be less-particularly when the less invasive procedure significantly extends the operating room time or requires additional monitors or costly disposables.     

Minimally invasive disc surgery. Nucleotomy versus fragmentectomy

There is continued debate as to the optimum surgical management of a herniated disc with sciatica. There are proponents of conventional microdiscectomy as well as those who advocate minimally invasive approaches, including central disc decompression or nucleotomy as well as arthroscopic lumbar microdiscectomy and fragmentectomy. In this controversy (I), Dr. Gary Onik takes the position that central disc decompression is both safe and efficacious and may be the procedure of choice for recurrent disc herniations (II). Dr. Parvis Kambin takes the opposing position and advocates arthroscopically assisted fragmentectomy as the procedure of choice.     

Minimally invasive surgery for coronary disease: a new alternative

To avoid the inflammatory syndrome generated by cardiopulmonary bypass, a new surgical technique, minimal invasive direct coronary artery bypass (MIDCAB), has been developed. An anastomosis is performed between the left internal mammary artery (LIMA) and the left anterior descending artery (LAD) on a beating heart, through a limited anterior thoracotomy. We describe our experience with this technique. Ten consecutive patients underwent a MIDCAB procedure. (9 males, age 65.9 +/- 9 years). There were 8 bypasses of the LIMA on the LAD, one bilateral mammary bypass on the LAD and the right coronary artery, and one conversion to a standard sternotomy with CPB for a saphenous vein bypass on the LAD because of injury to the LIMA (2nd case). There was one redo for haemostasis of the mammary artery bed (3rd case). The first 3 patients required postoperative blood transfusion. From the 4th operation onwards, with the introduction of new instrumentation which was better adapted to the narrowness of the surgical field, there were no further surgical complications. During the follow-up (mean 5 months; range 2-9), no patient suffered anginal recurrence. With the improvement of instrumentation, the MIDCAB technique offers satisfactory short- and mid-term results, while avoiding CPB with its adverse effects. Lastly, the cosmetic result is far better than with the conventional procedure.     

Minimally invasive surgery with the Port-Access method. Preliminary experience

METHODS: Data from the initial experience of 40 patients operated on with the Port-Access technique are reported. Indication to surgery was mitral disease in 24 patients and coronary stenosis in 16 patients. Mean age was 52 years (range 32-75). Operations performed were: 8 mitral valvuloplasties, 16 valve replacements, 9 single CABG (associated with an MVR in one case), 1 double CABG, 6 triple CABG and one quadruple CABG. Coronary endarterectomy was performed in 5 patients and left atrial isolation was associated with MV surgery in 5 cases. RESULTS: There were no operative deaths and every patient was discharged after a mean postoperative stay of 5.5 days (range 3-30). Postoperative course was complicated in 7 patients: surgical revision was necessary in 4 patients due to bleeding (through the mini-thoracotomy incision in 3 cases), 1 pacemaker was implanted for A-V block, one retained pulmonary catheter was removed through the mini-thoracotomy without the aid of cardiopulmonary bypass and in one case, there was an emergency conversion to median sternotomy due to a ventricular fibrillation unresponsive to usual resuscitative maneuvers a few hours after surgery. Some of these complications can be ascribed to the learning phase of this new technique and should disappear as experience is increased. CONCLUSIONS: Port-Access surgery is a new minimally invasive technique that utilizes a cardiopulmonary bypass with femoral access and a specialized catheter system that provides endoaortic clamping, pulmonary artery venting and myocardial preservation with infusion of cardioplegic solution in the aortic bulb or in the coronary sinus. Major contraindications to this technique are iliac-femoral disease or severe dilatation of ascending aorta. The aim of the Port-Access technique is to combine the aesthetic and functional advantages of the minimally invasive surgery with the wide range of surgical options that cardiopulmonary bypass can afford (to operate on atrioventricular valves and perform all the CABG that the patient need), without the limitations characteristic of the classic minimally invasive direct coronary artery bypass (MIDCAB) technique.     

Minimally invasive surgery in the management of Mirizzi syndrome]

BACKGROUND: Evidence accumulating over the last 10 years suggests that the exposed spinal cord tissue in a myelomeningocele sustains a secondary injury as the result of prolonged exposure to the intrauterine environment. These data suggest that early closure of the myelomeningocele sac might prevent such injury and in turn improve the neurologic outcome in the affected infant. METHODS: Three patients with fetuses carrying the ultrasonic diagnosis of myelomeningocele elected to enter a study of the feasibility of repairing myelomeningocele in utero. At approximately 28 weeks of gestation each patient underwent laparotomy and hysterotomy, thus exposing the myelomeningocele defect. The defect was closed in a routine surgical fashion, and the hysterotomy was then closed. RESULTS: The 3 patients recovered from surgery without incident. Early premature contractions subsided, and they were discharged by the 5th postoperative day. At between 33 and 36 weeks of gestation, each infant was delivered via cesarean section. The observed neurologic deficits were within the range expected from the anatomic level of the defects. Two of the infants have not required ventriculoperitoneal shunting. CONCLUSIONS: This limited series of patients suggests that myelomeningocele can be repaired in utero with minimal morbidity to either the mother or her fetus. A larger study will be needed to substantiate this low morbidity and to determine the extent of any neurologic benefit of early surgery.     

Facile minimally invasive cardiac surgery via ministernotomy

BACKGROUND: The public's and surgeons' perception of minimally invasive operations are frequently at odds. Nevertheless, real or perceived benefits may result from limiting skin and skeletal trauma. METHODS: Beginning in January 1996, we began approaching most infant and pediatric open heart procedures through an upper sternal split incision using a 1- to 3-inch skin opening and then extended this technique using a 2.5- to 3.5-inch incision for adult aortic and mitral valve replacement. RESULTS: A total of 82 patients, 57 infants and children and 25 adults, have been operated on using this approach (age range, newborn to 81 years). Operations accomplished through ministernotomy have included aortic valvotomy, arterial switch, tetralogy of Fallot, atrial or ventricular septal defect closure, aortic valve replacement, mitral valve replacement and repair, redo aortic or mitral valve replacement, double valve replacement, aortic root replacement, and complex arch reconstruction. In adults, the sternum was divided and then a T incision was made at the second, third, or fourth intercostal space. The mitral valve was reached through the roof of the left atrium. In children, a lower sternal split was used for atrial septal defect repairs. All cannulas were introduced through the ministernotomy incision, eliminating femoral cannulation. No new instruments, retractors, or ports were used. Mediastinal drainage was accomplished through a Blake drain connected to Heimlich-valved grenade suction. All but 2 patients were extubated immediately. Hospital stay was from 1 to 20 days (median 2 days). Patient and family acceptance is very high. CONCLUSIONS: On the basis of this initial experience, we attempt all congenital cardiac and isolated adult valve operations through ministernotomy.